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3486 lines
103 KiB
3486 lines
103 KiB
/*
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* Copyright (c) 2002 - 2005 NetGroup, Politecnico di Torino (Italy)
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* Copyright (c) 2005 - 2008 CACE Technologies, Davis (California)
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the Politecnico di Torino, CACE Technologies
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* nor the names of its contributors may be used to endorse or promote
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* products derived from this software without specific prior written
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* permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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*/
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#ifdef HAVE_CONFIG_H
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#include <config.h>
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#endif
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#include "ftmacros.h"
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#include <string.h> /* for strlen(), ... */
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#include <stdlib.h> /* for malloc(), free(), ... */
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#include <stdarg.h> /* for functions with variable number of arguments */
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#include <errno.h> /* for the errno variable */
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#include "sockutils.h"
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#include "pcap-int.h"
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#include "rpcap-protocol.h"
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#include "pcap-rpcap.h"
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#ifdef _WIN32
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#include "charconv.h" /* for utf_8_to_acp_truncated() */
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#endif
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#ifdef HAVE_OPENSSL
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#include "sslutils.h"
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#endif
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/*
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* This file contains the pcap module for capturing from a remote machine's
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* interfaces using the RPCAP protocol.
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*
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* WARNING: All the RPCAP functions that are allowed to return a buffer
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* containing the error description can return max PCAP_ERRBUF_SIZE characters.
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* However there is no guarantees that the string will be zero-terminated.
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* Best practice is to define the errbuf variable as a char of size
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* 'PCAP_ERRBUF_SIZE+1' and to insert manually a NULL character at the end
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* of the buffer. This will guarantee that no buffer overflows occur even
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* if we use the printf() to show the error on the screen.
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*
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* XXX - actually, null-terminating the error string is part of the
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* contract for the pcap API; if there's any place in the pcap code
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* that doesn't guarantee null-termination, even at the expense of
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* cutting the message short, that's a bug and needs to be fixed.
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*/
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#define PCAP_STATS_STANDARD 0 /* Used by pcap_stats_rpcap to see if we want standard or extended statistics */
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#ifdef _WIN32
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#define PCAP_STATS_EX 1 /* Used by pcap_stats_rpcap to see if we want standard or extended statistics */
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#endif
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/*
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* \brief Keeps a list of all the opened connections in the active mode.
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*
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* This structure defines a linked list of items that are needed to keep the info required to
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* manage the active mode.
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* In other words, when a new connection in active mode starts, this structure is updated so that
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* it reflects the list of active mode connections currently opened.
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* This structure is required by findalldevs() and open_remote() to see if they have to open a new
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* control connection toward the host, or they already have a control connection in place.
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*/
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struct activehosts
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{
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struct sockaddr_storage host;
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SOCKET sockctrl;
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SSL *ssl;
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uint8 protocol_version;
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struct activehosts *next;
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};
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/* Keeps a list of all the opened connections in the active mode. */
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static struct activehosts *activeHosts;
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/*
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* Keeps the main socket identifier when we want to accept a new remote
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* connection (active mode only).
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* See the documentation of pcap_remoteact_accept() and
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* pcap_remoteact_cleanup() for more details.
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*/
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static SOCKET sockmain;
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static SSL *ssl_main;
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/*
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* Private data for capturing remotely using the rpcap protocol.
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*/
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struct pcap_rpcap {
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/*
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* This is '1' if we're the network client; it is needed by several
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* functions (such as pcap_setfilter()) to know whether they have
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* to use the socket or have to open the local adapter.
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*/
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int rmt_clientside;
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SOCKET rmt_sockctrl; /* socket ID of the socket used for the control connection */
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SOCKET rmt_sockdata; /* socket ID of the socket used for the data connection */
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SSL *ctrl_ssl, *data_ssl; /* optional transport of rmt_sockctrl and rmt_sockdata via TLS */
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int rmt_flags; /* we have to save flags, since they are passed by the pcap_open_live(), but they are used by the pcap_startcapture() */
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int rmt_capstarted; /* 'true' if the capture is already started (needed to knoe if we have to call the pcap_startcapture() */
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char *currentfilter; /* Pointer to a buffer (allocated at run-time) that stores the current filter. Needed when flag PCAP_OPENFLAG_NOCAPTURE_RPCAP is turned on. */
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uint8 protocol_version; /* negotiated protocol version */
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uint8 uses_ssl; /* User asked for rpcaps scheme */
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unsigned int TotNetDrops; /* keeps the number of packets that have been dropped by the network */
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/*
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* This keeps the number of packets that have been received by the
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* application.
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*
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* Packets dropped by the kernel buffer are not counted in this
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* variable. It is always equal to (TotAccepted - TotDrops),
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* except for the case of remote capture, in which we have also
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* packets in flight, i.e. that have been transmitted by the remote
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* host, but that have not been received (yet) from the client.
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* In this case, (TotAccepted - TotDrops - TotNetDrops) gives a
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* wrong result, since this number does not corresponds always to
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* the number of packet received by the application. For this reason,
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* in the remote capture we need another variable that takes into
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* account of the number of packets actually received by the
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* application.
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*/
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unsigned int TotCapt;
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struct pcap_stat stat;
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/* XXX */
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struct pcap *next; /* list of open pcaps that need stuff cleared on close */
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};
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/****************************************************
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* *
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* Locally defined functions *
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* *
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****************************************************/
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static struct pcap_stat *rpcap_stats_rpcap(pcap_t *p, struct pcap_stat *ps, int mode);
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static int pcap_pack_bpffilter(pcap_t *fp, char *sendbuf, int *sendbufidx, struct bpf_program *prog);
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static int pcap_createfilter_norpcappkt(pcap_t *fp, struct bpf_program *prog);
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static int pcap_updatefilter_remote(pcap_t *fp, struct bpf_program *prog);
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static void pcap_save_current_filter_rpcap(pcap_t *fp, const char *filter);
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static int pcap_setfilter_rpcap(pcap_t *fp, struct bpf_program *prog);
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static int pcap_setsampling_remote(pcap_t *fp);
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static int pcap_startcapture_remote(pcap_t *fp);
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static int rpcap_recv_msg_header(SOCKET sock, SSL *, struct rpcap_header *header, char *errbuf);
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static int rpcap_check_msg_ver(SOCKET sock, SSL *, uint8 expected_ver, struct rpcap_header *header, char *errbuf);
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static int rpcap_check_msg_type(SOCKET sock, SSL *, uint8 request_type, struct rpcap_header *header, uint16 *errcode, char *errbuf);
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static int rpcap_process_msg_header(SOCKET sock, SSL *, uint8 ver, uint8 request_type, struct rpcap_header *header, char *errbuf);
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static int rpcap_recv(SOCKET sock, SSL *, void *buffer, size_t toread, uint32 *plen, char *errbuf);
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static void rpcap_msg_err(SOCKET sockctrl, SSL *, uint32 plen, char *remote_errbuf);
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static int rpcap_discard(SOCKET sock, SSL *, uint32 len, char *errbuf);
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static int rpcap_read_packet_msg(struct pcap_rpcap const *, pcap_t *p, size_t size);
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/****************************************************
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* *
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* Function bodies *
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* *
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****************************************************/
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/*
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* This function translates (i.e. de-serializes) a 'rpcap_sockaddr'
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* structure from the network byte order to a 'sockaddr_in" or
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* 'sockaddr_in6' structure in the host byte order.
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*
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* It accepts an 'rpcap_sockaddr' structure as it is received from the
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* network, and checks the address family field against various values
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* to see whether it looks like an IPv4 address, an IPv6 address, or
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* neither of those. It checks for multiple values in order to try
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* to handle older rpcap daemons that sent the native OS's 'sockaddr_in'
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* or 'sockaddr_in6' structures over the wire with some members
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* byte-swapped, and to handle the fact that AF_INET6 has different
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* values on different OSes.
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*
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* For IPv4 addresses, it converts the address family to host byte
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* order from network byte order and puts it into the structure,
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* sets the length if a sockaddr structure has a length, converts the
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* port number to host byte order from network byte order and puts
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* it into the structure, copies over the IPv4 address, and zeroes
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* out the zero padding.
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*
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* For IPv6 addresses, it converts the address family to host byte
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* order from network byte order and puts it into the structure,
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* sets the length if a sockaddr structure has a length, converts the
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* port number and flow information to host byte order from network
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* byte order and puts them into the structure, copies over the IPv6
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* address, and converts the scope ID to host byte order from network
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* byte order and puts it into the structure.
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*
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* The function will allocate the 'sockaddrout' variable according to the
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* address family in use. In case the address does not belong to the
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* AF_INET nor AF_INET6 families, 'sockaddrout' is not allocated and a
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* NULL pointer is returned. This usually happens because that address
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* does not exist on the other host, or is of an address family other
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* than AF_INET or AF_INET6, so the RPCAP daemon sent a 'sockaddr_storage'
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* structure containing all 'zero' values.
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*
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* Older RPCAPDs sent the addresses over the wire in the OS's native
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* structure format. For most OSes, this looks like the over-the-wire
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* format, but might have a different value for AF_INET6 than the value
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* on the machine receiving the reply. For OSes with the newer BSD-style
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* sockaddr structures, this has, instead of a 2-byte address family,
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* a 1-byte structure length followed by a 1-byte address family. The
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* RPCAPD code would put the address family in network byte order before
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* sending it; that would set it to 0 on a little-endian machine, as
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* htons() of any value between 1 and 255 would result in a value > 255,
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* with its lower 8 bits zero, so putting that back into a 1-byte field
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* would set it to 0.
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*
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* Therefore, for older RPCAPDs running on an OS with newer BSD-style
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* sockaddr structures, the family field, if treated as a big-endian
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* (network byte order) 16-bit field, would be:
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*
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* (length << 8) | family if sent by a big-endian machine
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* (length << 8) if sent by a little-endian machine
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*
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* For current RPCAPDs, and for older RPCAPDs running on an OS with
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* older BSD-style sockaddr structures, the family field, if treated
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* as a big-endian 16-bit field, would just contain the family.
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*
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* \param sockaddrin: a 'rpcap_sockaddr' pointer to the variable that has
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* to be de-serialized.
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*
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* \param sockaddrout: a 'sockaddr_storage' pointer to the variable that will contain
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* the de-serialized data. The structure returned can be either a 'sockaddr_in' or 'sockaddr_in6'.
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* This variable will be allocated automatically inside this function.
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*
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* \param errbuf: a pointer to a user-allocated buffer (of size PCAP_ERRBUF_SIZE)
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* that will contain the error message (in case there is one).
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*
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* \return '0' if everything is fine, '-1' if some errors occurred. Basically, the error
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* can be only the fact that the malloc() failed to allocate memory.
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* The error message is returned in the 'errbuf' variable, while the deserialized address
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* is returned into the 'sockaddrout' variable.
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*
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* \warning This function supports only AF_INET and AF_INET6 address families.
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*
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* \warning The sockaddrout (if not NULL) must be deallocated by the user.
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*/
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/*
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* Possible IPv4 family values other than the designated over-the-wire value,
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* which is 2 (because everybody uses 2 for AF_INET4).
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*/
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#define SOCKADDR_IN_LEN 16 /* length of struct sockaddr_in */
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#define SOCKADDR_IN6_LEN 28 /* length of struct sockaddr_in6 */
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#define NEW_BSD_AF_INET_BE ((SOCKADDR_IN_LEN << 8) | 2)
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#define NEW_BSD_AF_INET_LE (SOCKADDR_IN_LEN << 8)
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/*
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* Possible IPv6 family values other than the designated over-the-wire value,
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* which is 23 (because that's what Windows uses, and most RPCAP servers
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* out there are probably running Windows, as WinPcap includes the server
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* but few if any UN*Xes build and ship it).
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*
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* The new BSD sockaddr structure format was in place before 4.4-Lite, so
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* all the free-software BSDs use it.
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*/
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#define NEW_BSD_AF_INET6_BSD_BE ((SOCKADDR_IN6_LEN << 8) | 24) /* NetBSD, OpenBSD, BSD/OS */
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#define NEW_BSD_AF_INET6_FREEBSD_BE ((SOCKADDR_IN6_LEN << 8) | 28) /* FreeBSD, DragonFly BSD */
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#define NEW_BSD_AF_INET6_DARWIN_BE ((SOCKADDR_IN6_LEN << 8) | 30) /* macOS, iOS, anything else Darwin-based */
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#define NEW_BSD_AF_INET6_LE (SOCKADDR_IN6_LEN << 8)
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#define LINUX_AF_INET6 10
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#define HPUX_AF_INET6 22
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#define AIX_AF_INET6 24
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#define SOLARIS_AF_INET6 26
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static int
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rpcap_deseraddr(struct rpcap_sockaddr *sockaddrin, struct sockaddr_storage **sockaddrout, char *errbuf)
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{
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/* Warning: we support only AF_INET and AF_INET6 */
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switch (ntohs(sockaddrin->family))
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{
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case RPCAP_AF_INET:
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case NEW_BSD_AF_INET_BE:
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case NEW_BSD_AF_INET_LE:
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{
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struct rpcap_sockaddr_in *sockaddrin_ipv4;
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struct sockaddr_in *sockaddrout_ipv4;
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(*sockaddrout) = (struct sockaddr_storage *) malloc(sizeof(struct sockaddr_in));
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if ((*sockaddrout) == NULL)
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{
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pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
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errno, "malloc() failed");
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return -1;
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}
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sockaddrin_ipv4 = (struct rpcap_sockaddr_in *) sockaddrin;
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sockaddrout_ipv4 = (struct sockaddr_in *) (*sockaddrout);
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sockaddrout_ipv4->sin_family = AF_INET;
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sockaddrout_ipv4->sin_port = ntohs(sockaddrin_ipv4->port);
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memcpy(&sockaddrout_ipv4->sin_addr, &sockaddrin_ipv4->addr, sizeof(sockaddrout_ipv4->sin_addr));
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memset(sockaddrout_ipv4->sin_zero, 0, sizeof(sockaddrout_ipv4->sin_zero));
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break;
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}
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#ifdef AF_INET6
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case RPCAP_AF_INET6:
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case NEW_BSD_AF_INET6_BSD_BE:
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case NEW_BSD_AF_INET6_FREEBSD_BE:
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case NEW_BSD_AF_INET6_DARWIN_BE:
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case NEW_BSD_AF_INET6_LE:
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case LINUX_AF_INET6:
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case HPUX_AF_INET6:
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case AIX_AF_INET6:
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case SOLARIS_AF_INET6:
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{
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struct rpcap_sockaddr_in6 *sockaddrin_ipv6;
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struct sockaddr_in6 *sockaddrout_ipv6;
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(*sockaddrout) = (struct sockaddr_storage *) malloc(sizeof(struct sockaddr_in6));
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if ((*sockaddrout) == NULL)
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{
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pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
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errno, "malloc() failed");
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return -1;
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}
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sockaddrin_ipv6 = (struct rpcap_sockaddr_in6 *) sockaddrin;
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sockaddrout_ipv6 = (struct sockaddr_in6 *) (*sockaddrout);
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sockaddrout_ipv6->sin6_family = AF_INET6;
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sockaddrout_ipv6->sin6_port = ntohs(sockaddrin_ipv6->port);
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sockaddrout_ipv6->sin6_flowinfo = ntohl(sockaddrin_ipv6->flowinfo);
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memcpy(&sockaddrout_ipv6->sin6_addr, &sockaddrin_ipv6->addr, sizeof(sockaddrout_ipv6->sin6_addr));
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sockaddrout_ipv6->sin6_scope_id = ntohl(sockaddrin_ipv6->scope_id);
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break;
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}
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#endif
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default:
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/*
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* It is neither AF_INET nor AF_INET6 (or, if the OS doesn't
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* support AF_INET6, it's not AF_INET).
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*/
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*sockaddrout = NULL;
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break;
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}
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return 0;
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}
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|
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/*
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* This function reads a packet from the network socket. It does not
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* deliver the packet to a pcap_dispatch()/pcap_loop() callback (hence
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* the "nocb" string into its name).
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*
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* This function is called by pcap_read_rpcap().
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*
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* WARNING: By choice, this function does not make use of semaphores. A smarter
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* implementation should put a semaphore into the data thread, and a signal will
|
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* be raised as soon as there is data into the socket buffer.
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* However this is complicated and it does not bring any advantages when reading
|
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* from the network, in which network delays can be much more important than
|
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* these optimizations. Therefore, we chose the following approach:
|
|
* - the 'timeout' chosen by the user is split in two (half on the server side,
|
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* with the usual meaning, and half on the client side)
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* - this function checks for packets; if there are no packets, it waits for
|
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* timeout/2 and then it checks again. If packets are still missing, it returns,
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* otherwise it reads packets.
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*/
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static int pcap_read_nocb_remote(pcap_t *p, struct pcap_pkthdr *pkt_header, u_char **pkt_data)
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{
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struct pcap_rpcap *pr = p->priv; /* structure used when doing a remote live capture */
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struct rpcap_header *header; /* general header according to the RPCAP format */
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struct rpcap_pkthdr *net_pkt_header; /* header of the packet, from the message */
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u_char *net_pkt_data; /* packet data from the message */
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uint32 plen;
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int retval = 0; /* generic return value */
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int msglen;
|
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|
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/* Structures needed for the select() call */
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struct timeval tv; /* maximum time the select() can block waiting for data */
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fd_set rfds; /* set of socket descriptors we have to check */
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|
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/*
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* Define the packet buffer timeout, to be used in the select()
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* 'timeout', in pcap_t, is in milliseconds; we have to convert it into sec and microsec
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*/
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tv.tv_sec = p->opt.timeout / 1000;
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tv.tv_usec = (suseconds_t)((p->opt.timeout - tv.tv_sec * 1000) * 1000);
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|
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#ifdef HAVE_OPENSSL
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|
/* Check if we still have bytes available in the last decoded TLS record.
|
|
* If that's the case, we know SSL_read will not block. */
|
|
retval = pr->data_ssl && SSL_pending(pr->data_ssl) > 0;
|
|
#endif
|
|
if (! retval)
|
|
{
|
|
/* Watch out sockdata to see if it has input */
|
|
FD_ZERO(&rfds);
|
|
|
|
/*
|
|
* 'fp->rmt_sockdata' has always to be set before calling the select(),
|
|
* since it is cleared by the select()
|
|
*/
|
|
FD_SET(pr->rmt_sockdata, &rfds);
|
|
|
|
#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
|
|
retval = 1;
|
|
#else
|
|
retval = select((int) pr->rmt_sockdata + 1, &rfds, NULL, NULL, &tv);
|
|
#endif
|
|
|
|
if (retval == -1)
|
|
{
|
|
#ifndef _WIN32
|
|
if (errno == EINTR)
|
|
{
|
|
/* Interrupted. */
|
|
return 0;
|
|
}
|
|
#endif
|
|
sock_geterror("select()", p->errbuf, PCAP_ERRBUF_SIZE);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/* There is no data waiting, so return '0' */
|
|
if (retval == 0)
|
|
return 0;
|
|
|
|
/*
|
|
* We have to define 'header' as a pointer to a larger buffer,
|
|
* because in case of UDP we have to read all the message within a single call
|
|
*/
|
|
header = (struct rpcap_header *) p->buffer;
|
|
net_pkt_header = (struct rpcap_pkthdr *) ((char *)p->buffer + sizeof(struct rpcap_header));
|
|
net_pkt_data = (u_char *)p->buffer + sizeof(struct rpcap_header) + sizeof(struct rpcap_pkthdr);
|
|
|
|
if (pr->rmt_flags & PCAP_OPENFLAG_DATATX_UDP)
|
|
{
|
|
/* Read the entire message from the network */
|
|
msglen = sock_recv_dgram(pr->rmt_sockdata, pr->data_ssl, p->buffer,
|
|
p->bufsize, p->errbuf, PCAP_ERRBUF_SIZE);
|
|
if (msglen == -1)
|
|
{
|
|
/* Network error. */
|
|
return -1;
|
|
}
|
|
if (msglen == -3)
|
|
{
|
|
/* Interrupted receive. */
|
|
return 0;
|
|
}
|
|
if ((size_t)msglen < sizeof(struct rpcap_header))
|
|
{
|
|
/*
|
|
* Message is shorter than an rpcap header.
|
|
*/
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
|
|
"UDP packet message is shorter than an rpcap header");
|
|
return -1;
|
|
}
|
|
plen = ntohl(header->plen);
|
|
if ((size_t)msglen < sizeof(struct rpcap_header) + plen)
|
|
{
|
|
/*
|
|
* Message is shorter than the header claims it
|
|
* is.
|
|
*/
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
|
|
"UDP packet message is shorter than its rpcap header claims");
|
|
return -1;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
int status;
|
|
|
|
if ((size_t)p->cc < sizeof(struct rpcap_header))
|
|
{
|
|
/*
|
|
* We haven't read any of the packet header yet.
|
|
* The size we should get is the size of the
|
|
* packet header.
|
|
*/
|
|
status = rpcap_read_packet_msg(pr, p, sizeof(struct rpcap_header));
|
|
if (status == -1)
|
|
{
|
|
/* Network error. */
|
|
return -1;
|
|
}
|
|
if (status == -3)
|
|
{
|
|
/* Interrupted receive. */
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* We have the header, so we know how long the
|
|
* message payload is. The size we should get
|
|
* is the size of the packet header plus the
|
|
* size of the payload.
|
|
*/
|
|
plen = ntohl(header->plen);
|
|
if (plen > p->bufsize - sizeof(struct rpcap_header))
|
|
{
|
|
/*
|
|
* This is bigger than the largest
|
|
* record we'd expect. (We do it by
|
|
* subtracting in order to avoid an
|
|
* overflow.)
|
|
*/
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
|
|
"Server sent us a message larger than the largest expected packet message");
|
|
return -1;
|
|
}
|
|
status = rpcap_read_packet_msg(pr, p, sizeof(struct rpcap_header) + plen);
|
|
if (status == -1)
|
|
{
|
|
/* Network error. */
|
|
return -1;
|
|
}
|
|
if (status == -3)
|
|
{
|
|
/* Interrupted receive. */
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* We have the entire message; reset the buffer pointer
|
|
* and count, as the next read should start a new
|
|
* message.
|
|
*/
|
|
p->bp = p->buffer;
|
|
p->cc = 0;
|
|
}
|
|
|
|
/*
|
|
* We have the entire message.
|
|
*/
|
|
header->plen = plen;
|
|
|
|
/*
|
|
* Did the server specify the version we negotiated?
|
|
*/
|
|
if (rpcap_check_msg_ver(pr->rmt_sockdata, pr->data_ssl, pr->protocol_version,
|
|
header, p->errbuf) == -1)
|
|
{
|
|
return 0; /* Return 'no packets received' */
|
|
}
|
|
|
|
/*
|
|
* Is this a RPCAP_MSG_PACKET message?
|
|
*/
|
|
if (header->type != RPCAP_MSG_PACKET)
|
|
{
|
|
return 0; /* Return 'no packets received' */
|
|
}
|
|
|
|
if (ntohl(net_pkt_header->caplen) > plen)
|
|
{
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
|
|
"Packet's captured data goes past the end of the received packet message.");
|
|
return -1;
|
|
}
|
|
|
|
/* Fill in packet header */
|
|
pkt_header->caplen = ntohl(net_pkt_header->caplen);
|
|
pkt_header->len = ntohl(net_pkt_header->len);
|
|
pkt_header->ts.tv_sec = ntohl(net_pkt_header->timestamp_sec);
|
|
pkt_header->ts.tv_usec = ntohl(net_pkt_header->timestamp_usec);
|
|
|
|
/* Supply a pointer to the beginning of the packet data */
|
|
*pkt_data = net_pkt_data;
|
|
|
|
/*
|
|
* I don't update the counter of the packets dropped by the network since we're using TCP,
|
|
* therefore no packets are dropped. Just update the number of packets received correctly
|
|
*/
|
|
pr->TotCapt++;
|
|
|
|
if (pr->rmt_flags & PCAP_OPENFLAG_DATATX_UDP)
|
|
{
|
|
unsigned int npkt;
|
|
|
|
/* We're using UDP, so we need to update the counter of the packets dropped by the network */
|
|
npkt = ntohl(net_pkt_header->npkt);
|
|
|
|
if (pr->TotCapt != npkt)
|
|
{
|
|
pr->TotNetDrops += (npkt - pr->TotCapt);
|
|
pr->TotCapt = npkt;
|
|
}
|
|
}
|
|
|
|
/* Packet read successfully */
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* This function reads a packet from the network socket.
|
|
*
|
|
* This function relies on the pcap_read_nocb_remote to deliver packets. The
|
|
* difference, here, is that as soon as a packet is read, it is delivered
|
|
* to the application by means of a callback function.
|
|
*/
|
|
static int pcap_read_rpcap(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
|
|
{
|
|
struct pcap_rpcap *pr = p->priv; /* structure used when doing a remote live capture */
|
|
struct pcap_pkthdr pkt_header;
|
|
u_char *pkt_data;
|
|
int n = 0;
|
|
int ret;
|
|
|
|
/*
|
|
* If this is client-side, and we haven't already started
|
|
* the capture, start it now.
|
|
*/
|
|
if (pr->rmt_clientside)
|
|
{
|
|
/* We are on an remote capture */
|
|
if (!pr->rmt_capstarted)
|
|
{
|
|
/*
|
|
* The capture isn't started yet, so try to
|
|
* start it.
|
|
*/
|
|
if (pcap_startcapture_remote(p))
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
while (n < cnt || PACKET_COUNT_IS_UNLIMITED(cnt))
|
|
{
|
|
/*
|
|
* Has "pcap_breakloop()" been called?
|
|
*/
|
|
if (p->break_loop) {
|
|
/*
|
|
* Yes - clear the flag that indicates that it
|
|
* has, and return PCAP_ERROR_BREAK to indicate
|
|
* that we were told to break out of the loop.
|
|
*/
|
|
p->break_loop = 0;
|
|
return (PCAP_ERROR_BREAK);
|
|
}
|
|
|
|
/*
|
|
* Read some packets.
|
|
*/
|
|
ret = pcap_read_nocb_remote(p, &pkt_header, &pkt_data);
|
|
if (ret == 1)
|
|
{
|
|
/*
|
|
* We got a packet. Hand it to the callback
|
|
* and count it so we can return the count.
|
|
*/
|
|
(*callback)(user, &pkt_header, pkt_data);
|
|
n++;
|
|
}
|
|
else if (ret == -1)
|
|
{
|
|
/* Error. */
|
|
return ret;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* No packet; this could mean that we timed
|
|
* out, or that we got interrupted, or that
|
|
* we got a bad packet.
|
|
*
|
|
* Were we told to break out of the loop?
|
|
*/
|
|
if (p->break_loop) {
|
|
/*
|
|
* Yes.
|
|
*/
|
|
p->break_loop = 0;
|
|
return (PCAP_ERROR_BREAK);
|
|
}
|
|
/* No - return the number of packets we've processed. */
|
|
return n;
|
|
}
|
|
}
|
|
return n;
|
|
}
|
|
|
|
/*
|
|
* This function sends a CLOSE command to the capture server if we're in
|
|
* passive mode and an ENDCAP command to the capture server if we're in
|
|
* active mode.
|
|
*
|
|
* It is called when the user calls pcap_close(). It sends a command
|
|
* to our peer that says 'ok, let's stop capturing'.
|
|
*
|
|
* WARNING: Since we're closing the connection, we do not check for errors.
|
|
*/
|
|
static void pcap_cleanup_rpcap(pcap_t *fp)
|
|
{
|
|
struct pcap_rpcap *pr = fp->priv; /* structure used when doing a remote live capture */
|
|
struct rpcap_header header; /* header of the RPCAP packet */
|
|
struct activehosts *temp; /* temp var needed to scan the host list chain, to detect if we're in active mode */
|
|
int active = 0; /* active mode or not? */
|
|
|
|
/* detect if we're in active mode */
|
|
temp = activeHosts;
|
|
while (temp)
|
|
{
|
|
if (temp->sockctrl == pr->rmt_sockctrl)
|
|
{
|
|
active = 1;
|
|
break;
|
|
}
|
|
temp = temp->next;
|
|
}
|
|
|
|
if (!active)
|
|
{
|
|
rpcap_createhdr(&header, pr->protocol_version,
|
|
RPCAP_MSG_CLOSE, 0, 0);
|
|
|
|
/*
|
|
* Send the close request; don't report any errors, as
|
|
* we're closing this pcap_t, and have no place to report
|
|
* the error. No reply is sent to this message.
|
|
*/
|
|
(void)sock_send(pr->rmt_sockctrl, pr->ctrl_ssl, (char *)&header,
|
|
sizeof(struct rpcap_header), NULL, 0);
|
|
}
|
|
else
|
|
{
|
|
rpcap_createhdr(&header, pr->protocol_version,
|
|
RPCAP_MSG_ENDCAP_REQ, 0, 0);
|
|
|
|
/*
|
|
* Send the end capture request; don't report any errors,
|
|
* as we're closing this pcap_t, and have no place to
|
|
* report the error.
|
|
*/
|
|
if (sock_send(pr->rmt_sockctrl, pr->ctrl_ssl, (char *)&header,
|
|
sizeof(struct rpcap_header), NULL, 0) == 0)
|
|
{
|
|
/*
|
|
* Wait for the answer; don't report any errors,
|
|
* as we're closing this pcap_t, and have no
|
|
* place to report the error.
|
|
*/
|
|
if (rpcap_process_msg_header(pr->rmt_sockctrl, pr->ctrl_ssl,
|
|
pr->protocol_version, RPCAP_MSG_ENDCAP_REQ,
|
|
&header, NULL) == 0)
|
|
{
|
|
(void)rpcap_discard(pr->rmt_sockctrl, pr->ctrl_ssl,
|
|
header.plen, NULL);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (pr->rmt_sockdata)
|
|
{
|
|
#ifdef HAVE_OPENSSL
|
|
if (pr->data_ssl)
|
|
{
|
|
// Finish using the SSL handle for the data socket.
|
|
// This must be done *before* the socket is closed.
|
|
ssl_finish(pr->data_ssl);
|
|
pr->data_ssl = NULL;
|
|
}
|
|
#endif
|
|
sock_close(pr->rmt_sockdata, NULL, 0);
|
|
pr->rmt_sockdata = 0;
|
|
}
|
|
|
|
if ((!active) && (pr->rmt_sockctrl))
|
|
{
|
|
#ifdef HAVE_OPENSSL
|
|
if (pr->ctrl_ssl)
|
|
{
|
|
// Finish using the SSL handle for the control socket.
|
|
// This must be done *before* the socket is closed.
|
|
ssl_finish(pr->ctrl_ssl);
|
|
pr->ctrl_ssl = NULL;
|
|
}
|
|
#endif
|
|
sock_close(pr->rmt_sockctrl, NULL, 0);
|
|
}
|
|
|
|
pr->rmt_sockctrl = 0;
|
|
pr->ctrl_ssl = NULL;
|
|
|
|
if (pr->currentfilter)
|
|
{
|
|
free(pr->currentfilter);
|
|
pr->currentfilter = NULL;
|
|
}
|
|
|
|
pcap_cleanup_live_common(fp);
|
|
|
|
/* To avoid inconsistencies in the number of sock_init() */
|
|
sock_cleanup();
|
|
}
|
|
|
|
/*
|
|
* This function retrieves network statistics from our peer;
|
|
* it provides only the standard statistics.
|
|
*/
|
|
static int pcap_stats_rpcap(pcap_t *p, struct pcap_stat *ps)
|
|
{
|
|
struct pcap_stat *retval;
|
|
|
|
retval = rpcap_stats_rpcap(p, ps, PCAP_STATS_STANDARD);
|
|
|
|
if (retval)
|
|
return 0;
|
|
else
|
|
return -1;
|
|
}
|
|
|
|
#ifdef _WIN32
|
|
/*
|
|
* This function retrieves network statistics from our peer;
|
|
* it provides the additional statistics supported by pcap_stats_ex().
|
|
*/
|
|
static struct pcap_stat *pcap_stats_ex_rpcap(pcap_t *p, int *pcap_stat_size)
|
|
{
|
|
*pcap_stat_size = sizeof (p->stat);
|
|
|
|
/* PCAP_STATS_EX (third param) means 'extended pcap_stats()' */
|
|
return (rpcap_stats_rpcap(p, &(p->stat), PCAP_STATS_EX));
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* This function retrieves network statistics from our peer. It
|
|
* is used by the two previous functions.
|
|
*
|
|
* It can be called in two modes:
|
|
* - PCAP_STATS_STANDARD: if we want just standard statistics (i.e.,
|
|
* for pcap_stats())
|
|
* - PCAP_STATS_EX: if we want extended statistics (i.e., for
|
|
* pcap_stats_ex())
|
|
*
|
|
* This 'mode' parameter is needed because in pcap_stats() the variable that
|
|
* keeps the statistics is allocated by the user. On Windows, this structure
|
|
* has been extended in order to keep new stats. However, if the user has a
|
|
* smaller structure and it passes it to pcap_stats(), this function will
|
|
* try to fill in more data than the size of the structure, so that memory
|
|
* after the structure will be overwritten.
|
|
*
|
|
* So, we need to know it we have to copy just the standard fields, or the
|
|
* extended fields as well.
|
|
*
|
|
* In case we want to copy the extended fields as well, the problem of
|
|
* memory overflow no longer exists because the structure that's filled
|
|
* in is part of the pcap_t, so that it can be guaranteed to be large
|
|
* enough for the additional statistics.
|
|
*
|
|
* \param p: the pcap_t structure related to the current instance.
|
|
*
|
|
* \param ps: a pointer to a 'pcap_stat' structure, needed for compatibility
|
|
* with pcap_stat(), where the structure is allocated by the user. In case
|
|
* of pcap_stats_ex(), this structure and the function return value point
|
|
* to the same variable.
|
|
*
|
|
* \param mode: one of PCAP_STATS_STANDARD or PCAP_STATS_EX.
|
|
*
|
|
* \return The structure that keeps the statistics, or NULL in case of error.
|
|
* The error string is placed in the pcap_t structure.
|
|
*/
|
|
static struct pcap_stat *rpcap_stats_rpcap(pcap_t *p, struct pcap_stat *ps, int mode)
|
|
{
|
|
struct pcap_rpcap *pr = p->priv; /* structure used when doing a remote live capture */
|
|
struct rpcap_header header; /* header of the RPCAP packet */
|
|
struct rpcap_stats netstats; /* statistics sent on the network */
|
|
uint32 plen; /* data remaining in the message */
|
|
|
|
#ifdef _WIN32
|
|
if (mode != PCAP_STATS_STANDARD && mode != PCAP_STATS_EX)
|
|
#else
|
|
if (mode != PCAP_STATS_STANDARD)
|
|
#endif
|
|
{
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
|
|
"Invalid stats mode %d", mode);
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* If the capture has not yet started, we cannot request statistics
|
|
* for the capture from our peer, so we return 0 for all statistics,
|
|
* as nothing's been seen yet.
|
|
*/
|
|
if (!pr->rmt_capstarted)
|
|
{
|
|
ps->ps_drop = 0;
|
|
ps->ps_ifdrop = 0;
|
|
ps->ps_recv = 0;
|
|
#ifdef _WIN32
|
|
if (mode == PCAP_STATS_EX)
|
|
{
|
|
ps->ps_capt = 0;
|
|
ps->ps_sent = 0;
|
|
ps->ps_netdrop = 0;
|
|
}
|
|
#endif /* _WIN32 */
|
|
|
|
return ps;
|
|
}
|
|
|
|
rpcap_createhdr(&header, pr->protocol_version,
|
|
RPCAP_MSG_STATS_REQ, 0, 0);
|
|
|
|
/* Send the PCAP_STATS command */
|
|
if (sock_send(pr->rmt_sockctrl, pr->ctrl_ssl, (char *)&header,
|
|
sizeof(struct rpcap_header), p->errbuf, PCAP_ERRBUF_SIZE) < 0)
|
|
return NULL; /* Unrecoverable network error */
|
|
|
|
/* Receive and process the reply message header. */
|
|
if (rpcap_process_msg_header(pr->rmt_sockctrl, pr->ctrl_ssl, pr->protocol_version,
|
|
RPCAP_MSG_STATS_REQ, &header, p->errbuf) == -1)
|
|
return NULL; /* Error */
|
|
|
|
plen = header.plen;
|
|
|
|
/* Read the reply body */
|
|
if (rpcap_recv(pr->rmt_sockctrl, pr->ctrl_ssl, (char *)&netstats,
|
|
sizeof(struct rpcap_stats), &plen, p->errbuf) == -1)
|
|
goto error;
|
|
|
|
ps->ps_drop = ntohl(netstats.krnldrop);
|
|
ps->ps_ifdrop = ntohl(netstats.ifdrop);
|
|
ps->ps_recv = ntohl(netstats.ifrecv);
|
|
#ifdef _WIN32
|
|
if (mode == PCAP_STATS_EX)
|
|
{
|
|
ps->ps_capt = pr->TotCapt;
|
|
ps->ps_netdrop = pr->TotNetDrops;
|
|
ps->ps_sent = ntohl(netstats.svrcapt);
|
|
}
|
|
#endif /* _WIN32 */
|
|
|
|
/* Discard the rest of the message. */
|
|
if (rpcap_discard(pr->rmt_sockctrl, pr->ctrl_ssl, plen, p->errbuf) == -1)
|
|
goto error_nodiscard;
|
|
|
|
return ps;
|
|
|
|
error:
|
|
/*
|
|
* Discard the rest of the message.
|
|
* We already reported an error; if this gets an error, just
|
|
* drive on.
|
|
*/
|
|
(void)rpcap_discard(pr->rmt_sockctrl, pr->ctrl_ssl, plen, NULL);
|
|
|
|
error_nodiscard:
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* This function returns the entry in the list of active hosts for this
|
|
* active connection (active mode only), or NULL if there is no
|
|
* active connection or an error occurred. It is just for internal
|
|
* use.
|
|
*
|
|
* \param host: a string that keeps the host name of the host for which we
|
|
* want to get the socket ID for that active connection.
|
|
*
|
|
* \param error: a pointer to an int that is set to 1 if an error occurred
|
|
* and 0 otherwise.
|
|
*
|
|
* \param errbuf: a pointer to a user-allocated buffer (of size
|
|
* PCAP_ERRBUF_SIZE) that will contain the error message (in case
|
|
* there is one).
|
|
*
|
|
* \return the entry for this host in the list of active connections
|
|
* if found, NULL if it's not found or there's an error.
|
|
*/
|
|
static struct activehosts *
|
|
rpcap_remoteact_getsock(const char *host, int *error, char *errbuf)
|
|
{
|
|
struct activehosts *temp; /* temp var needed to scan the host list chain */
|
|
struct addrinfo hints, *addrinfo, *ai_next; /* temp var needed to translate between hostname to its address */
|
|
int retval;
|
|
|
|
/* retrieve the network address corresponding to 'host' */
|
|
addrinfo = NULL;
|
|
memset(&hints, 0, sizeof(struct addrinfo));
|
|
hints.ai_family = PF_UNSPEC;
|
|
hints.ai_socktype = SOCK_STREAM;
|
|
|
|
retval = getaddrinfo(host, "0", &hints, &addrinfo);
|
|
if (retval != 0)
|
|
{
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "getaddrinfo() %s",
|
|
gai_strerror(retval));
|
|
*error = 1;
|
|
return NULL;
|
|
}
|
|
|
|
temp = activeHosts;
|
|
|
|
while (temp)
|
|
{
|
|
ai_next = addrinfo;
|
|
while (ai_next)
|
|
{
|
|
if (sock_cmpaddr(&temp->host, (struct sockaddr_storage *) ai_next->ai_addr) == 0)
|
|
{
|
|
*error = 0;
|
|
freeaddrinfo(addrinfo);
|
|
return temp;
|
|
}
|
|
|
|
ai_next = ai_next->ai_next;
|
|
}
|
|
temp = temp->next;
|
|
}
|
|
|
|
if (addrinfo)
|
|
freeaddrinfo(addrinfo);
|
|
|
|
/*
|
|
* The host for which you want to get the socket ID does not have an
|
|
* active connection.
|
|
*/
|
|
*error = 0;
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* This function starts a remote capture.
|
|
*
|
|
* This function is required since the RPCAP protocol decouples the 'open'
|
|
* from the 'start capture' functions.
|
|
* This function takes all the parameters needed (which have been stored
|
|
* into the pcap_t structure) and sends them to the server.
|
|
*
|
|
* \param fp: the pcap_t descriptor of the device currently open.
|
|
*
|
|
* \return '0' if everything is fine, '-1' otherwise. The error message
|
|
* (if one) is returned into the 'errbuf' field of the pcap_t structure.
|
|
*/
|
|
static int pcap_startcapture_remote(pcap_t *fp)
|
|
{
|
|
struct pcap_rpcap *pr = fp->priv; /* structure used when doing a remote live capture */
|
|
char sendbuf[RPCAP_NETBUF_SIZE]; /* temporary buffer in which data to be sent is buffered */
|
|
int sendbufidx = 0; /* index which keeps the number of bytes currently buffered */
|
|
char portdata[PCAP_BUF_SIZE]; /* temp variable needed to keep the network port for the data connection */
|
|
uint32 plen;
|
|
int active = 0; /* '1' if we're in active mode */
|
|
struct activehosts *temp; /* temp var needed to scan the host list chain, to detect if we're in active mode */
|
|
char host[INET6_ADDRSTRLEN + 1]; /* numeric name of the other host */
|
|
|
|
/* socket-related variables*/
|
|
struct addrinfo hints; /* temp, needed to open a socket connection */
|
|
struct addrinfo *addrinfo; /* temp, needed to open a socket connection */
|
|
SOCKET sockdata = 0; /* socket descriptor of the data connection */
|
|
struct sockaddr_storage saddr; /* temp, needed to retrieve the network data port chosen on the local machine */
|
|
socklen_t saddrlen; /* temp, needed to retrieve the network data port chosen on the local machine */
|
|
int ai_family; /* temp, keeps the address family used by the control connection */
|
|
|
|
/* RPCAP-related variables*/
|
|
struct rpcap_header header; /* header of the RPCAP packet */
|
|
struct rpcap_startcapreq *startcapreq; /* start capture request message */
|
|
struct rpcap_startcapreply startcapreply; /* start capture reply message */
|
|
|
|
/* Variables related to the buffer setting */
|
|
int res;
|
|
socklen_t itemp;
|
|
int sockbufsize = 0;
|
|
uint32 server_sockbufsize;
|
|
|
|
// Take the opportunity to clear pr->data_ssl before any goto error,
|
|
// as it seems pr->priv is not zeroed after its malloced.
|
|
pr->data_ssl = NULL;
|
|
|
|
/*
|
|
* Let's check if sampling has been required.
|
|
* If so, let's set it first
|
|
*/
|
|
if (pcap_setsampling_remote(fp) != 0)
|
|
return -1;
|
|
|
|
/* detect if we're in active mode */
|
|
temp = activeHosts;
|
|
while (temp)
|
|
{
|
|
if (temp->sockctrl == pr->rmt_sockctrl)
|
|
{
|
|
active = 1;
|
|
break;
|
|
}
|
|
temp = temp->next;
|
|
}
|
|
|
|
addrinfo = NULL;
|
|
|
|
/*
|
|
* Gets the complete sockaddr structure used in the ctrl connection
|
|
* This is needed to get the address family of the control socket
|
|
* Tip: I cannot save the ai_family of the ctrl sock in the pcap_t struct,
|
|
* since the ctrl socket can already be open in case of active mode;
|
|
* so I would have to call getpeername() anyway
|
|
*/
|
|
saddrlen = sizeof(struct sockaddr_storage);
|
|
if (getpeername(pr->rmt_sockctrl, (struct sockaddr *) &saddr, &saddrlen) == -1)
|
|
{
|
|
sock_geterror("getsockname()", fp->errbuf, PCAP_ERRBUF_SIZE);
|
|
goto error_nodiscard;
|
|
}
|
|
ai_family = ((struct sockaddr_storage *) &saddr)->ss_family;
|
|
|
|
/* Get the numeric address of the remote host we are connected to */
|
|
if (getnameinfo((struct sockaddr *) &saddr, saddrlen, host,
|
|
sizeof(host), NULL, 0, NI_NUMERICHOST))
|
|
{
|
|
sock_geterror("getnameinfo()", fp->errbuf, PCAP_ERRBUF_SIZE);
|
|
goto error_nodiscard;
|
|
}
|
|
|
|
/*
|
|
* Data connection is opened by the server toward the client if:
|
|
* - we're using TCP, and the user wants us to be in active mode
|
|
* - we're using UDP
|
|
*/
|
|
if ((active) || (pr->rmt_flags & PCAP_OPENFLAG_DATATX_UDP))
|
|
{
|
|
/*
|
|
* We have to create a new socket to receive packets
|
|
* We have to do that immediately, since we have to tell the other
|
|
* end which network port we picked up
|
|
*/
|
|
memset(&hints, 0, sizeof(struct addrinfo));
|
|
/* TEMP addrinfo is NULL in case of active */
|
|
hints.ai_family = ai_family; /* Use the same address family of the control socket */
|
|
hints.ai_socktype = (pr->rmt_flags & PCAP_OPENFLAG_DATATX_UDP) ? SOCK_DGRAM : SOCK_STREAM;
|
|
hints.ai_flags = AI_PASSIVE; /* Data connection is opened by the server toward the client */
|
|
|
|
/* Let's the server pick up a free network port for us */
|
|
if (sock_initaddress(NULL, "0", &hints, &addrinfo, fp->errbuf, PCAP_ERRBUF_SIZE) == -1)
|
|
goto error_nodiscard;
|
|
|
|
if ((sockdata = sock_open(addrinfo, SOCKOPEN_SERVER,
|
|
1 /* max 1 connection in queue */, fp->errbuf, PCAP_ERRBUF_SIZE)) == INVALID_SOCKET)
|
|
goto error_nodiscard;
|
|
|
|
/* addrinfo is no longer used */
|
|
freeaddrinfo(addrinfo);
|
|
addrinfo = NULL;
|
|
|
|
/* get the complete sockaddr structure used in the data connection */
|
|
saddrlen = sizeof(struct sockaddr_storage);
|
|
if (getsockname(sockdata, (struct sockaddr *) &saddr, &saddrlen) == -1)
|
|
{
|
|
sock_geterror("getsockname()", fp->errbuf, PCAP_ERRBUF_SIZE);
|
|
goto error_nodiscard;
|
|
}
|
|
|
|
/* Get the local port the system picked up */
|
|
if (getnameinfo((struct sockaddr *) &saddr, saddrlen, NULL,
|
|
0, portdata, sizeof(portdata), NI_NUMERICSERV))
|
|
{
|
|
sock_geterror("getnameinfo()", fp->errbuf, PCAP_ERRBUF_SIZE);
|
|
goto error_nodiscard;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Now it's time to start playing with the RPCAP protocol
|
|
* RPCAP start capture command: create the request message
|
|
*/
|
|
if (sock_bufferize(NULL, sizeof(struct rpcap_header), NULL,
|
|
&sendbufidx, RPCAP_NETBUF_SIZE, SOCKBUF_CHECKONLY, fp->errbuf, PCAP_ERRBUF_SIZE))
|
|
goto error_nodiscard;
|
|
|
|
rpcap_createhdr((struct rpcap_header *) sendbuf,
|
|
pr->protocol_version, RPCAP_MSG_STARTCAP_REQ, 0,
|
|
sizeof(struct rpcap_startcapreq) + sizeof(struct rpcap_filter) + fp->fcode.bf_len * sizeof(struct rpcap_filterbpf_insn));
|
|
|
|
/* Fill the structure needed to open an adapter remotely */
|
|
startcapreq = (struct rpcap_startcapreq *) &sendbuf[sendbufidx];
|
|
|
|
if (sock_bufferize(NULL, sizeof(struct rpcap_startcapreq), NULL,
|
|
&sendbufidx, RPCAP_NETBUF_SIZE, SOCKBUF_CHECKONLY, fp->errbuf, PCAP_ERRBUF_SIZE))
|
|
goto error_nodiscard;
|
|
|
|
memset(startcapreq, 0, sizeof(struct rpcap_startcapreq));
|
|
|
|
/* By default, apply half the timeout on one side, half of the other */
|
|
fp->opt.timeout = fp->opt.timeout / 2;
|
|
startcapreq->read_timeout = htonl(fp->opt.timeout);
|
|
|
|
/* portdata on the openreq is meaningful only if we're in active mode */
|
|
if ((active) || (pr->rmt_flags & PCAP_OPENFLAG_DATATX_UDP))
|
|
{
|
|
sscanf(portdata, "%d", (int *)&(startcapreq->portdata)); /* cast to avoid a compiler warning */
|
|
startcapreq->portdata = htons(startcapreq->portdata);
|
|
}
|
|
|
|
startcapreq->snaplen = htonl(fp->snapshot);
|
|
startcapreq->flags = 0;
|
|
|
|
if (pr->rmt_flags & PCAP_OPENFLAG_PROMISCUOUS)
|
|
startcapreq->flags |= RPCAP_STARTCAPREQ_FLAG_PROMISC;
|
|
if (pr->rmt_flags & PCAP_OPENFLAG_DATATX_UDP)
|
|
startcapreq->flags |= RPCAP_STARTCAPREQ_FLAG_DGRAM;
|
|
if (active)
|
|
startcapreq->flags |= RPCAP_STARTCAPREQ_FLAG_SERVEROPEN;
|
|
|
|
startcapreq->flags = htons(startcapreq->flags);
|
|
|
|
/* Pack the capture filter */
|
|
if (pcap_pack_bpffilter(fp, &sendbuf[sendbufidx], &sendbufidx, &fp->fcode))
|
|
goto error_nodiscard;
|
|
|
|
if (sock_send(pr->rmt_sockctrl, pr->ctrl_ssl, sendbuf, sendbufidx, fp->errbuf,
|
|
PCAP_ERRBUF_SIZE) < 0)
|
|
goto error_nodiscard;
|
|
|
|
/* Receive and process the reply message header. */
|
|
if (rpcap_process_msg_header(pr->rmt_sockctrl, pr->ctrl_ssl, pr->protocol_version,
|
|
RPCAP_MSG_STARTCAP_REQ, &header, fp->errbuf) == -1)
|
|
goto error_nodiscard;
|
|
|
|
plen = header.plen;
|
|
|
|
if (rpcap_recv(pr->rmt_sockctrl, pr->ctrl_ssl, (char *)&startcapreply,
|
|
sizeof(struct rpcap_startcapreply), &plen, fp->errbuf) == -1)
|
|
goto error;
|
|
|
|
/*
|
|
* In case of UDP data stream, the connection is always opened by the daemon
|
|
* So, this case is already covered by the code above.
|
|
* Now, we have still to handle TCP connections, because:
|
|
* - if we're in active mode, we have to wait for a remote connection
|
|
* - if we're in passive more, we have to start a connection
|
|
*
|
|
* We have to do he job in two steps because in case we're opening a TCP connection, we have
|
|
* to tell the port we're using to the remote side; in case we're accepting a TCP
|
|
* connection, we have to wait this info from the remote side.
|
|
*/
|
|
if (!(pr->rmt_flags & PCAP_OPENFLAG_DATATX_UDP))
|
|
{
|
|
if (!active)
|
|
{
|
|
memset(&hints, 0, sizeof(struct addrinfo));
|
|
hints.ai_family = ai_family; /* Use the same address family of the control socket */
|
|
hints.ai_socktype = (pr->rmt_flags & PCAP_OPENFLAG_DATATX_UDP) ? SOCK_DGRAM : SOCK_STREAM;
|
|
snprintf(portdata, PCAP_BUF_SIZE, "%d", ntohs(startcapreply.portdata));
|
|
|
|
/* Let's the server pick up a free network port for us */
|
|
if (sock_initaddress(host, portdata, &hints, &addrinfo, fp->errbuf, PCAP_ERRBUF_SIZE) == -1)
|
|
goto error;
|
|
|
|
if ((sockdata = sock_open(addrinfo, SOCKOPEN_CLIENT, 0, fp->errbuf, PCAP_ERRBUF_SIZE)) == INVALID_SOCKET)
|
|
goto error;
|
|
|
|
/* addrinfo is no longer used */
|
|
freeaddrinfo(addrinfo);
|
|
addrinfo = NULL;
|
|
}
|
|
else
|
|
{
|
|
SOCKET socktemp; /* We need another socket, since we're going to accept() a connection */
|
|
|
|
/* Connection creation */
|
|
saddrlen = sizeof(struct sockaddr_storage);
|
|
|
|
socktemp = accept(sockdata, (struct sockaddr *) &saddr, &saddrlen);
|
|
|
|
if (socktemp == INVALID_SOCKET)
|
|
{
|
|
sock_geterror("accept()", fp->errbuf, PCAP_ERRBUF_SIZE);
|
|
goto error;
|
|
}
|
|
|
|
/* Now that I accepted the connection, the server socket is no longer needed */
|
|
sock_close(sockdata, fp->errbuf, PCAP_ERRBUF_SIZE);
|
|
sockdata = socktemp;
|
|
}
|
|
}
|
|
|
|
/* Let's save the socket of the data connection */
|
|
pr->rmt_sockdata = sockdata;
|
|
|
|
#ifdef HAVE_OPENSSL
|
|
if (pr->uses_ssl)
|
|
{
|
|
pr->data_ssl = ssl_promotion(0, sockdata, fp->errbuf, PCAP_ERRBUF_SIZE);
|
|
if (! pr->data_ssl) goto error;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Set the size of the socket buffer for the data socket.
|
|
* It has the same size as the local capture buffer used
|
|
* on the other side of the connection.
|
|
*/
|
|
server_sockbufsize = ntohl(startcapreply.bufsize);
|
|
|
|
/* Let's get the actual size of the socket buffer */
|
|
itemp = sizeof(sockbufsize);
|
|
|
|
res = getsockopt(sockdata, SOL_SOCKET, SO_RCVBUF, (char *)&sockbufsize, &itemp);
|
|
if (res == -1)
|
|
{
|
|
sock_geterror("pcap_startcapture_remote(): getsockopt() failed", fp->errbuf, PCAP_ERRBUF_SIZE);
|
|
goto error;
|
|
}
|
|
|
|
/*
|
|
* Warning: on some kernels (e.g. Linux), the size of the user
|
|
* buffer does not take into account the pcap_header and such,
|
|
* and it is set equal to the snaplen.
|
|
*
|
|
* In my view, this is wrong (the meaning of the bufsize became
|
|
* a bit strange). So, here bufsize is the whole size of the
|
|
* user buffer. In case the bufsize returned is too small,
|
|
* let's adjust it accordingly.
|
|
*/
|
|
if (server_sockbufsize <= (u_int) fp->snapshot)
|
|
server_sockbufsize += sizeof(struct pcap_pkthdr);
|
|
|
|
/* if the current socket buffer is smaller than the desired one */
|
|
if ((u_int) sockbufsize < server_sockbufsize)
|
|
{
|
|
/*
|
|
* Loop until the buffer size is OK or the original
|
|
* socket buffer size is larger than this one.
|
|
*/
|
|
for (;;)
|
|
{
|
|
res = setsockopt(sockdata, SOL_SOCKET, SO_RCVBUF,
|
|
(char *)&(server_sockbufsize),
|
|
sizeof(server_sockbufsize));
|
|
|
|
if (res == 0)
|
|
break;
|
|
|
|
/*
|
|
* If something goes wrong, halve the buffer size
|
|
* (checking that it does not become smaller than
|
|
* the current one).
|
|
*/
|
|
server_sockbufsize /= 2;
|
|
|
|
if ((u_int) sockbufsize >= server_sockbufsize)
|
|
{
|
|
server_sockbufsize = sockbufsize;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Let's allocate the packet; this is required in order to put
|
|
* the packet somewhere when extracting data from the socket.
|
|
* Since buffering has already been done in the socket buffer,
|
|
* here we need just a buffer whose size is equal to the
|
|
* largest possible packet message for the snapshot size,
|
|
* namely the length of the message header plus the length
|
|
* of the packet header plus the snapshot length.
|
|
*/
|
|
fp->bufsize = sizeof(struct rpcap_header) + sizeof(struct rpcap_pkthdr) + fp->snapshot;
|
|
|
|
fp->buffer = (u_char *)malloc(fp->bufsize);
|
|
if (fp->buffer == NULL)
|
|
{
|
|
pcap_fmt_errmsg_for_errno(fp->errbuf, PCAP_ERRBUF_SIZE,
|
|
errno, "malloc");
|
|
goto error;
|
|
}
|
|
|
|
/*
|
|
* The buffer is currently empty.
|
|
*/
|
|
fp->bp = fp->buffer;
|
|
fp->cc = 0;
|
|
|
|
/* Discard the rest of the message. */
|
|
if (rpcap_discard(pr->rmt_sockctrl, pr->ctrl_ssl, plen, fp->errbuf) == -1)
|
|
goto error_nodiscard;
|
|
|
|
/*
|
|
* In case the user does not want to capture RPCAP packets, let's update the filter
|
|
* We have to update it here (instead of sending it into the 'StartCapture' message
|
|
* because when we generate the 'start capture' we do not know (yet) all the ports
|
|
* we're currently using.
|
|
*/
|
|
if (pr->rmt_flags & PCAP_OPENFLAG_NOCAPTURE_RPCAP)
|
|
{
|
|
struct bpf_program fcode;
|
|
|
|
if (pcap_createfilter_norpcappkt(fp, &fcode) == -1)
|
|
goto error;
|
|
|
|
/* We cannot use 'pcap_setfilter_rpcap' because formally the capture has not been started yet */
|
|
/* (the 'pr->rmt_capstarted' variable will be updated some lines below) */
|
|
if (pcap_updatefilter_remote(fp, &fcode) == -1)
|
|
goto error;
|
|
|
|
pcap_freecode(&fcode);
|
|
}
|
|
|
|
pr->rmt_capstarted = 1;
|
|
return 0;
|
|
|
|
error:
|
|
/*
|
|
* When the connection has been established, we have to close it. So, at the
|
|
* beginning of this function, if an error occur we return immediately with
|
|
* a return NULL; when the connection is established, we have to come here
|
|
* ('goto error;') in order to close everything properly.
|
|
*/
|
|
|
|
/*
|
|
* Discard the rest of the message.
|
|
* We already reported an error; if this gets an error, just
|
|
* drive on.
|
|
*/
|
|
(void)rpcap_discard(pr->rmt_sockctrl, pr->ctrl_ssl, plen, NULL);
|
|
|
|
error_nodiscard:
|
|
#ifdef HAVE_OPENSSL
|
|
if (pr->data_ssl)
|
|
{
|
|
// Finish using the SSL handle for the data socket.
|
|
// This must be done *before* the socket is closed.
|
|
ssl_finish(pr->data_ssl);
|
|
pr->data_ssl = NULL;
|
|
}
|
|
#endif
|
|
|
|
/* we can be here because sockdata said 'error' */
|
|
if ((sockdata != 0) && (sockdata != INVALID_SOCKET))
|
|
sock_close(sockdata, NULL, 0);
|
|
|
|
if (!active)
|
|
{
|
|
#ifdef HAVE_OPENSSL
|
|
if (pr->ctrl_ssl)
|
|
{
|
|
// Finish using the SSL handle for the control socket.
|
|
// This must be done *before* the socket is closed.
|
|
ssl_finish(pr->ctrl_ssl);
|
|
pr->ctrl_ssl = NULL;
|
|
}
|
|
#endif
|
|
sock_close(pr->rmt_sockctrl, NULL, 0);
|
|
}
|
|
|
|
if (addrinfo != NULL)
|
|
freeaddrinfo(addrinfo);
|
|
|
|
/*
|
|
* We do not have to call pcap_close() here, because this function is always called
|
|
* by the user in case something bad happens
|
|
*/
|
|
#if 0
|
|
if (fp)
|
|
{
|
|
pcap_close(fp);
|
|
fp= NULL;
|
|
}
|
|
#endif
|
|
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* This function takes a bpf program and sends it to the other host.
|
|
*
|
|
* This function can be called in two cases:
|
|
* - pcap_startcapture_remote() is called (we have to send the filter
|
|
* along with the 'start capture' command)
|
|
* - we want to update the filter during a capture (i.e. pcap_setfilter()
|
|
* after the capture has been started)
|
|
*
|
|
* This function serializes the filter into the sending buffer ('sendbuf',
|
|
* passed as a parameter) and return back. It does not send anything on
|
|
* the network.
|
|
*
|
|
* \param fp: the pcap_t descriptor of the device currently opened.
|
|
*
|
|
* \param sendbuf: the buffer on which the serialized data has to copied.
|
|
*
|
|
* \param sendbufidx: it is used to return the abounf of bytes copied into the buffer.
|
|
*
|
|
* \param prog: the bpf program we have to copy.
|
|
*
|
|
* \return '0' if everything is fine, '-1' otherwise. The error message (if one)
|
|
* is returned into the 'errbuf' field of the pcap_t structure.
|
|
*/
|
|
static int pcap_pack_bpffilter(pcap_t *fp, char *sendbuf, int *sendbufidx, struct bpf_program *prog)
|
|
{
|
|
struct rpcap_filter *filter;
|
|
struct rpcap_filterbpf_insn *insn;
|
|
struct bpf_insn *bf_insn;
|
|
struct bpf_program fake_prog; /* To be used just in case the user forgot to set a filter */
|
|
unsigned int i;
|
|
|
|
if (prog->bf_len == 0) /* No filters have been specified; so, let's apply a "fake" filter */
|
|
{
|
|
if (pcap_compile(fp, &fake_prog, NULL /* buffer */, 1, 0) == -1)
|
|
return -1;
|
|
|
|
prog = &fake_prog;
|
|
}
|
|
|
|
filter = (struct rpcap_filter *) sendbuf;
|
|
|
|
if (sock_bufferize(NULL, sizeof(struct rpcap_filter), NULL, sendbufidx,
|
|
RPCAP_NETBUF_SIZE, SOCKBUF_CHECKONLY, fp->errbuf, PCAP_ERRBUF_SIZE))
|
|
return -1;
|
|
|
|
filter->filtertype = htons(RPCAP_UPDATEFILTER_BPF);
|
|
filter->nitems = htonl((int32)prog->bf_len);
|
|
|
|
if (sock_bufferize(NULL, prog->bf_len * sizeof(struct rpcap_filterbpf_insn),
|
|
NULL, sendbufidx, RPCAP_NETBUF_SIZE, SOCKBUF_CHECKONLY, fp->errbuf, PCAP_ERRBUF_SIZE))
|
|
return -1;
|
|
|
|
insn = (struct rpcap_filterbpf_insn *) (filter + 1);
|
|
bf_insn = prog->bf_insns;
|
|
|
|
for (i = 0; i < prog->bf_len; i++)
|
|
{
|
|
insn->code = htons(bf_insn->code);
|
|
insn->jf = bf_insn->jf;
|
|
insn->jt = bf_insn->jt;
|
|
insn->k = htonl(bf_insn->k);
|
|
|
|
insn++;
|
|
bf_insn++;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* This function updates a filter on a remote host.
|
|
*
|
|
* It is called when the user wants to update a filter.
|
|
* In case we're capturing from the network, it sends the filter to our
|
|
* peer.
|
|
* This function is *not* called automatically when the user calls
|
|
* pcap_setfilter().
|
|
* There will be two cases:
|
|
* - the capture has been started: in this case, pcap_setfilter_rpcap()
|
|
* calls pcap_updatefilter_remote()
|
|
* - the capture has not started yet: in this case, pcap_setfilter_rpcap()
|
|
* stores the filter into the pcap_t structure, and then the filter is
|
|
* sent with pcap_startcap().
|
|
*
|
|
* WARNING This function *does not* clear the packet currently into the
|
|
* buffers. Therefore, the user has to expect to receive some packets
|
|
* that are related to the previous filter. If you want to discard all
|
|
* the packets before applying a new filter, you have to close the
|
|
* current capture session and start a new one.
|
|
*
|
|
* XXX - we really should have pcap_setfilter() always discard packets
|
|
* received with the old filter, and have a separate pcap_setfilter_noflush()
|
|
* function that doesn't discard any packets.
|
|
*/
|
|
static int pcap_updatefilter_remote(pcap_t *fp, struct bpf_program *prog)
|
|
{
|
|
struct pcap_rpcap *pr = fp->priv; /* structure used when doing a remote live capture */
|
|
char sendbuf[RPCAP_NETBUF_SIZE]; /* temporary buffer in which data to be sent is buffered */
|
|
int sendbufidx = 0; /* index which keeps the number of bytes currently buffered */
|
|
struct rpcap_header header; /* To keep the reply message */
|
|
|
|
if (sock_bufferize(NULL, sizeof(struct rpcap_header), NULL, &sendbufidx,
|
|
RPCAP_NETBUF_SIZE, SOCKBUF_CHECKONLY, fp->errbuf, PCAP_ERRBUF_SIZE))
|
|
return -1;
|
|
|
|
rpcap_createhdr((struct rpcap_header *) sendbuf,
|
|
pr->protocol_version, RPCAP_MSG_UPDATEFILTER_REQ, 0,
|
|
sizeof(struct rpcap_filter) + prog->bf_len * sizeof(struct rpcap_filterbpf_insn));
|
|
|
|
if (pcap_pack_bpffilter(fp, &sendbuf[sendbufidx], &sendbufidx, prog))
|
|
return -1;
|
|
|
|
if (sock_send(pr->rmt_sockctrl, pr->ctrl_ssl, sendbuf, sendbufidx, fp->errbuf,
|
|
PCAP_ERRBUF_SIZE) < 0)
|
|
return -1;
|
|
|
|
/* Receive and process the reply message header. */
|
|
if (rpcap_process_msg_header(pr->rmt_sockctrl, pr->ctrl_ssl, pr->protocol_version,
|
|
RPCAP_MSG_UPDATEFILTER_REQ, &header, fp->errbuf) == -1)
|
|
return -1;
|
|
|
|
/*
|
|
* It shouldn't have any contents; discard it if it does.
|
|
*/
|
|
if (rpcap_discard(pr->rmt_sockctrl, pr->ctrl_ssl, header.plen, fp->errbuf) == -1)
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void
|
|
pcap_save_current_filter_rpcap(pcap_t *fp, const char *filter)
|
|
{
|
|
struct pcap_rpcap *pr = fp->priv; /* structure used when doing a remote live capture */
|
|
|
|
/*
|
|
* Check if:
|
|
* - We are on an remote capture
|
|
* - we do not want to capture RPCAP traffic
|
|
*
|
|
* If so, we have to save the current filter, because we have to
|
|
* add some piece of stuff later
|
|
*/
|
|
if (pr->rmt_clientside &&
|
|
(pr->rmt_flags & PCAP_OPENFLAG_NOCAPTURE_RPCAP))
|
|
{
|
|
if (pr->currentfilter)
|
|
free(pr->currentfilter);
|
|
|
|
if (filter == NULL)
|
|
filter = "";
|
|
|
|
pr->currentfilter = strdup(filter);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This function sends a filter to a remote host.
|
|
*
|
|
* This function is called when the user wants to set a filter.
|
|
* It sends the filter to our peer.
|
|
* This function is called automatically when the user calls pcap_setfilter().
|
|
*
|
|
* Parameters and return values are exactly the same of pcap_setfilter().
|
|
*/
|
|
static int pcap_setfilter_rpcap(pcap_t *fp, struct bpf_program *prog)
|
|
{
|
|
struct pcap_rpcap *pr = fp->priv; /* structure used when doing a remote live capture */
|
|
|
|
if (!pr->rmt_capstarted)
|
|
{
|
|
/* copy filter into the pcap_t structure */
|
|
if (install_bpf_program(fp, prog) == -1)
|
|
return -1;
|
|
return 0;
|
|
}
|
|
|
|
/* we have to update a filter during run-time */
|
|
if (pcap_updatefilter_remote(fp, prog))
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* This function updates the current filter in order not to capture rpcap
|
|
* packets.
|
|
*
|
|
* This function is called *only* when the user wants exclude RPCAP packets
|
|
* related to the current session from the captured packets.
|
|
*
|
|
* \return '0' if everything is fine, '-1' otherwise. The error message (if one)
|
|
* is returned into the 'errbuf' field of the pcap_t structure.
|
|
*/
|
|
static int pcap_createfilter_norpcappkt(pcap_t *fp, struct bpf_program *prog)
|
|
{
|
|
struct pcap_rpcap *pr = fp->priv; /* structure used when doing a remote live capture */
|
|
int RetVal = 0;
|
|
|
|
/* We do not want to capture our RPCAP traffic. So, let's update the filter */
|
|
if (pr->rmt_flags & PCAP_OPENFLAG_NOCAPTURE_RPCAP)
|
|
{
|
|
struct sockaddr_storage saddr; /* temp, needed to retrieve the network data port chosen on the local machine */
|
|
socklen_t saddrlen; /* temp, needed to retrieve the network data port chosen on the local machine */
|
|
char myaddress[128];
|
|
char myctrlport[128];
|
|
char mydataport[128];
|
|
char peeraddress[128];
|
|
char peerctrlport[128];
|
|
char *newfilter;
|
|
|
|
/* Get the name/port of our peer */
|
|
saddrlen = sizeof(struct sockaddr_storage);
|
|
if (getpeername(pr->rmt_sockctrl, (struct sockaddr *) &saddr, &saddrlen) == -1)
|
|
{
|
|
sock_geterror("getpeername()", fp->errbuf, PCAP_ERRBUF_SIZE);
|
|
return -1;
|
|
}
|
|
|
|
if (getnameinfo((struct sockaddr *) &saddr, saddrlen, peeraddress,
|
|
sizeof(peeraddress), peerctrlport, sizeof(peerctrlport), NI_NUMERICHOST | NI_NUMERICSERV))
|
|
{
|
|
sock_geterror("getnameinfo()", fp->errbuf, PCAP_ERRBUF_SIZE);
|
|
return -1;
|
|
}
|
|
|
|
/* We cannot check the data port, because this is available only in case of TCP sockets */
|
|
/* Get the name/port of the current host */
|
|
if (getsockname(pr->rmt_sockctrl, (struct sockaddr *) &saddr, &saddrlen) == -1)
|
|
{
|
|
sock_geterror("getsockname()", fp->errbuf, PCAP_ERRBUF_SIZE);
|
|
return -1;
|
|
}
|
|
|
|
/* Get the local port the system picked up */
|
|
if (getnameinfo((struct sockaddr *) &saddr, saddrlen, myaddress,
|
|
sizeof(myaddress), myctrlport, sizeof(myctrlport), NI_NUMERICHOST | NI_NUMERICSERV))
|
|
{
|
|
sock_geterror("getnameinfo()", fp->errbuf, PCAP_ERRBUF_SIZE);
|
|
return -1;
|
|
}
|
|
|
|
/* Let's now check the data port */
|
|
if (getsockname(pr->rmt_sockdata, (struct sockaddr *) &saddr, &saddrlen) == -1)
|
|
{
|
|
sock_geterror("getsockname()", fp->errbuf, PCAP_ERRBUF_SIZE);
|
|
return -1;
|
|
}
|
|
|
|
/* Get the local port the system picked up */
|
|
if (getnameinfo((struct sockaddr *) &saddr, saddrlen, NULL, 0, mydataport, sizeof(mydataport), NI_NUMERICSERV))
|
|
{
|
|
sock_geterror("getnameinfo()", fp->errbuf, PCAP_ERRBUF_SIZE);
|
|
return -1;
|
|
}
|
|
|
|
if (pr->currentfilter && pr->currentfilter[0] != '\0')
|
|
{
|
|
/*
|
|
* We have a current filter; add items to it to
|
|
* filter out this rpcap session.
|
|
*/
|
|
if (pcap_asprintf(&newfilter,
|
|
"(%s) and not (host %s and host %s and port %s and port %s) and not (host %s and host %s and port %s)",
|
|
pr->currentfilter, myaddress, peeraddress,
|
|
myctrlport, peerctrlport, myaddress, peeraddress,
|
|
mydataport) == -1)
|
|
{
|
|
/* Failed. */
|
|
snprintf(fp->errbuf, PCAP_ERRBUF_SIZE,
|
|
"Can't allocate memory for new filter");
|
|
return -1;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* We have no current filter; construct a filter to
|
|
* filter out this rpcap session.
|
|
*/
|
|
if (pcap_asprintf(&newfilter,
|
|
"not (host %s and host %s and port %s and port %s) and not (host %s and host %s and port %s)",
|
|
myaddress, peeraddress, myctrlport, peerctrlport,
|
|
myaddress, peeraddress, mydataport) == -1)
|
|
{
|
|
/* Failed. */
|
|
snprintf(fp->errbuf, PCAP_ERRBUF_SIZE,
|
|
"Can't allocate memory for new filter");
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This is only an hack to prevent the save_current_filter
|
|
* routine, which will be called when we call pcap_compile(),
|
|
* from saving the modified filter.
|
|
*/
|
|
pr->rmt_clientside = 0;
|
|
|
|
if (pcap_compile(fp, prog, newfilter, 1, 0) == -1)
|
|
RetVal = -1;
|
|
|
|
/* Undo the hack. */
|
|
pr->rmt_clientside = 1;
|
|
|
|
free(newfilter);
|
|
}
|
|
|
|
return RetVal;
|
|
}
|
|
|
|
/*
|
|
* This function sets sampling parameters in the remote host.
|
|
*
|
|
* It is called when the user wants to set activate sampling on the
|
|
* remote host.
|
|
*
|
|
* Sampling parameters are defined into the 'pcap_t' structure.
|
|
*
|
|
* \param p: the pcap_t descriptor of the device currently opened.
|
|
*
|
|
* \return '0' if everything is OK, '-1' is something goes wrong. The
|
|
* error message is returned in the 'errbuf' member of the pcap_t structure.
|
|
*/
|
|
static int pcap_setsampling_remote(pcap_t *fp)
|
|
{
|
|
struct pcap_rpcap *pr = fp->priv; /* structure used when doing a remote live capture */
|
|
char sendbuf[RPCAP_NETBUF_SIZE];/* temporary buffer in which data to be sent is buffered */
|
|
int sendbufidx = 0; /* index which keeps the number of bytes currently buffered */
|
|
struct rpcap_header header; /* To keep the reply message */
|
|
struct rpcap_sampling *sampling_pars; /* Structure that is needed to send sampling parameters to the remote host */
|
|
|
|
/* If no samping is requested, return 'ok' */
|
|
if (fp->rmt_samp.method == PCAP_SAMP_NOSAMP)
|
|
return 0;
|
|
|
|
/*
|
|
* Check for sampling parameters that don't fit in a message.
|
|
* We'll let the server complain about invalid parameters
|
|
* that do fit into the message.
|
|
*/
|
|
if (fp->rmt_samp.method < 0 || fp->rmt_samp.method > 255) {
|
|
snprintf(fp->errbuf, PCAP_ERRBUF_SIZE,
|
|
"Invalid sampling method %d", fp->rmt_samp.method);
|
|
return -1;
|
|
}
|
|
if (fp->rmt_samp.value < 0 || fp->rmt_samp.value > 65535) {
|
|
snprintf(fp->errbuf, PCAP_ERRBUF_SIZE,
|
|
"Invalid sampling value %d", fp->rmt_samp.value);
|
|
return -1;
|
|
}
|
|
|
|
if (sock_bufferize(NULL, sizeof(struct rpcap_header), NULL,
|
|
&sendbufidx, RPCAP_NETBUF_SIZE, SOCKBUF_CHECKONLY, fp->errbuf, PCAP_ERRBUF_SIZE))
|
|
return -1;
|
|
|
|
rpcap_createhdr((struct rpcap_header *) sendbuf,
|
|
pr->protocol_version, RPCAP_MSG_SETSAMPLING_REQ, 0,
|
|
sizeof(struct rpcap_sampling));
|
|
|
|
/* Fill the structure needed to open an adapter remotely */
|
|
sampling_pars = (struct rpcap_sampling *) &sendbuf[sendbufidx];
|
|
|
|
if (sock_bufferize(NULL, sizeof(struct rpcap_sampling), NULL,
|
|
&sendbufidx, RPCAP_NETBUF_SIZE, SOCKBUF_CHECKONLY, fp->errbuf, PCAP_ERRBUF_SIZE))
|
|
return -1;
|
|
|
|
memset(sampling_pars, 0, sizeof(struct rpcap_sampling));
|
|
|
|
sampling_pars->method = (uint8)fp->rmt_samp.method;
|
|
sampling_pars->value = (uint16)htonl(fp->rmt_samp.value);
|
|
|
|
if (sock_send(pr->rmt_sockctrl, pr->ctrl_ssl, sendbuf, sendbufidx, fp->errbuf,
|
|
PCAP_ERRBUF_SIZE) < 0)
|
|
return -1;
|
|
|
|
/* Receive and process the reply message header. */
|
|
if (rpcap_process_msg_header(pr->rmt_sockctrl, pr->ctrl_ssl, pr->protocol_version,
|
|
RPCAP_MSG_SETSAMPLING_REQ, &header, fp->errbuf) == -1)
|
|
return -1;
|
|
|
|
/*
|
|
* It shouldn't have any contents; discard it if it does.
|
|
*/
|
|
if (rpcap_discard(pr->rmt_sockctrl, pr->ctrl_ssl, header.plen, fp->errbuf) == -1)
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*********************************************************
|
|
* *
|
|
* Miscellaneous functions *
|
|
* *
|
|
*********************************************************/
|
|
|
|
/*
|
|
* This function performs authentication and protocol version
|
|
* negotiation. It is required in order to open the connection
|
|
* with the other end party.
|
|
*
|
|
* It sends authentication parameters on the control socket and
|
|
* reads the reply. If the reply is a success indication, it
|
|
* checks whether the reply includes minimum and maximum supported
|
|
* versions from the server; if not, it assumes both are 0, as
|
|
* that means it's an older server that doesn't return supported
|
|
* version numbers in authentication replies, so it only supports
|
|
* version 0. It then tries to determine the maximum version
|
|
* supported both by us and by the server. If it can find such a
|
|
* version, it sets us up to use that version; otherwise, it fails,
|
|
* indicating that there is no version supported by us and by the
|
|
* server.
|
|
*
|
|
* \param sock: the socket we are currently using.
|
|
*
|
|
* \param ver: pointer to variable to which to set the protocol version
|
|
* number we selected.
|
|
*
|
|
* \param auth: authentication parameters that have to be sent.
|
|
*
|
|
* \param errbuf: a pointer to a user-allocated buffer (of size
|
|
* PCAP_ERRBUF_SIZE) that will contain the error message (in case there
|
|
* is one). It could be a network problem or the fact that the authorization
|
|
* failed.
|
|
*
|
|
* \return '0' if everything is fine, '-1' for an error. For errors,
|
|
* an error message string is returned in the 'errbuf' variable.
|
|
*/
|
|
static int rpcap_doauth(SOCKET sockctrl, SSL *ssl, uint8 *ver, struct pcap_rmtauth *auth, char *errbuf)
|
|
{
|
|
char sendbuf[RPCAP_NETBUF_SIZE]; /* temporary buffer in which data that has to be sent is buffered */
|
|
int sendbufidx = 0; /* index which keeps the number of bytes currently buffered */
|
|
uint16 length; /* length of the payload of this message */
|
|
struct rpcap_auth *rpauth;
|
|
uint16 auth_type;
|
|
struct rpcap_header header;
|
|
size_t str_length;
|
|
uint32 plen;
|
|
struct rpcap_authreply authreply; /* authentication reply message */
|
|
uint8 ourvers;
|
|
|
|
if (auth)
|
|
{
|
|
switch (auth->type)
|
|
{
|
|
case RPCAP_RMTAUTH_NULL:
|
|
length = sizeof(struct rpcap_auth);
|
|
break;
|
|
|
|
case RPCAP_RMTAUTH_PWD:
|
|
length = sizeof(struct rpcap_auth);
|
|
if (auth->username)
|
|
{
|
|
str_length = strlen(auth->username);
|
|
if (str_length > 65535)
|
|
{
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "User name is too long (> 65535 bytes)");
|
|
return -1;
|
|
}
|
|
length += (uint16)str_length;
|
|
}
|
|
if (auth->password)
|
|
{
|
|
str_length = strlen(auth->password);
|
|
if (str_length > 65535)
|
|
{
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "Password is too long (> 65535 bytes)");
|
|
return -1;
|
|
}
|
|
length += (uint16)str_length;
|
|
}
|
|
break;
|
|
|
|
default:
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "Authentication type not recognized.");
|
|
return -1;
|
|
}
|
|
|
|
auth_type = (uint16)auth->type;
|
|
}
|
|
else
|
|
{
|
|
auth_type = RPCAP_RMTAUTH_NULL;
|
|
length = sizeof(struct rpcap_auth);
|
|
}
|
|
|
|
if (sock_bufferize(NULL, sizeof(struct rpcap_header), NULL,
|
|
&sendbufidx, RPCAP_NETBUF_SIZE, SOCKBUF_CHECKONLY, errbuf, PCAP_ERRBUF_SIZE))
|
|
return -1;
|
|
|
|
rpcap_createhdr((struct rpcap_header *) sendbuf, 0,
|
|
RPCAP_MSG_AUTH_REQ, 0, length);
|
|
|
|
rpauth = (struct rpcap_auth *) &sendbuf[sendbufidx];
|
|
|
|
if (sock_bufferize(NULL, sizeof(struct rpcap_auth), NULL,
|
|
&sendbufidx, RPCAP_NETBUF_SIZE, SOCKBUF_CHECKONLY, errbuf, PCAP_ERRBUF_SIZE))
|
|
return -1;
|
|
|
|
memset(rpauth, 0, sizeof(struct rpcap_auth));
|
|
|
|
rpauth->type = htons(auth_type);
|
|
|
|
if (auth_type == RPCAP_RMTAUTH_PWD)
|
|
{
|
|
if (auth->username)
|
|
rpauth->slen1 = (uint16)strlen(auth->username);
|
|
else
|
|
rpauth->slen1 = 0;
|
|
|
|
if (sock_bufferize(auth->username, rpauth->slen1, sendbuf,
|
|
&sendbufidx, RPCAP_NETBUF_SIZE, SOCKBUF_BUFFERIZE, errbuf, PCAP_ERRBUF_SIZE))
|
|
return -1;
|
|
|
|
if (auth->password)
|
|
rpauth->slen2 = (uint16)strlen(auth->password);
|
|
else
|
|
rpauth->slen2 = 0;
|
|
|
|
if (sock_bufferize(auth->password, rpauth->slen2, sendbuf,
|
|
&sendbufidx, RPCAP_NETBUF_SIZE, SOCKBUF_BUFFERIZE, errbuf, PCAP_ERRBUF_SIZE))
|
|
return -1;
|
|
|
|
rpauth->slen1 = htons(rpauth->slen1);
|
|
rpauth->slen2 = htons(rpauth->slen2);
|
|
}
|
|
|
|
if (sock_send(sockctrl, ssl, sendbuf, sendbufidx, errbuf,
|
|
PCAP_ERRBUF_SIZE) < 0)
|
|
return -1;
|
|
|
|
/* Receive and process the reply message header */
|
|
if (rpcap_process_msg_header(sockctrl, ssl, 0, RPCAP_MSG_AUTH_REQ,
|
|
&header, errbuf) == -1)
|
|
return -1;
|
|
|
|
/*
|
|
* OK, it's an authentication reply, so we're logged in.
|
|
*
|
|
* Did it send any additional information?
|
|
*/
|
|
plen = header.plen;
|
|
if (plen != 0)
|
|
{
|
|
/* Yes - is it big enough to be version information? */
|
|
if (plen < sizeof(struct rpcap_authreply))
|
|
{
|
|
/* No - discard it and fail. */
|
|
(void)rpcap_discard(sockctrl, ssl, plen, NULL);
|
|
return -1;
|
|
}
|
|
|
|
/* Read the reply body */
|
|
if (rpcap_recv(sockctrl, ssl, (char *)&authreply,
|
|
sizeof(struct rpcap_authreply), &plen, errbuf) == -1)
|
|
{
|
|
(void)rpcap_discard(sockctrl, ssl, plen, NULL);
|
|
return -1;
|
|
}
|
|
|
|
/* Discard the rest of the message, if there is any. */
|
|
if (rpcap_discard(sockctrl, ssl, plen, errbuf) == -1)
|
|
return -1;
|
|
|
|
/*
|
|
* Check the minimum and maximum versions for sanity;
|
|
* the minimum must be <= the maximum.
|
|
*/
|
|
if (authreply.minvers > authreply.maxvers)
|
|
{
|
|
/*
|
|
* Bogus - give up on this server.
|
|
*/
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
|
"The server's minimum supported protocol version is greater than its maximum supported protocol version");
|
|
return -1;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* No - it supports only version 0. */
|
|
authreply.minvers = 0;
|
|
authreply.maxvers = 0;
|
|
}
|
|
|
|
/*
|
|
* OK, let's start with the maximum version the server supports.
|
|
*/
|
|
ourvers = authreply.maxvers;
|
|
|
|
#if RPCAP_MIN_VERSION != 0
|
|
/*
|
|
* If that's less than the minimum version we support, we
|
|
* can't communicate.
|
|
*/
|
|
if (ourvers < RPCAP_MIN_VERSION)
|
|
goto novers;
|
|
#endif
|
|
|
|
/*
|
|
* If that's greater than the maximum version we support,
|
|
* choose the maximum version we support.
|
|
*/
|
|
if (ourvers > RPCAP_MAX_VERSION)
|
|
{
|
|
ourvers = RPCAP_MAX_VERSION;
|
|
|
|
/*
|
|
* If that's less than the minimum version they
|
|
* support, we can't communicate.
|
|
*/
|
|
if (ourvers < authreply.minvers)
|
|
goto novers;
|
|
}
|
|
|
|
*ver = ourvers;
|
|
return 0;
|
|
|
|
novers:
|
|
/*
|
|
* There is no version we both support; that is a fatal error.
|
|
*/
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
|
"The server doesn't support any protocol version that we support");
|
|
return -1;
|
|
}
|
|
|
|
/* We don't currently support non-blocking mode. */
|
|
static int
|
|
pcap_getnonblock_rpcap(pcap_t *p)
|
|
{
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
|
|
"Non-blocking mode isn't supported for capturing remotely with rpcap");
|
|
return (-1);
|
|
}
|
|
|
|
static int
|
|
pcap_setnonblock_rpcap(pcap_t *p, int nonblock _U_)
|
|
{
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
|
|
"Non-blocking mode isn't supported for capturing remotely with rpcap");
|
|
return (-1);
|
|
}
|
|
|
|
static int
|
|
rpcap_setup_session(const char *source, struct pcap_rmtauth *auth,
|
|
int *activep, SOCKET *sockctrlp, uint8 *uses_sslp, SSL **sslp,
|
|
int rmt_flags, uint8 *protocol_versionp, char *host, char *port,
|
|
char *iface, char *errbuf)
|
|
{
|
|
int type;
|
|
struct activehosts *activeconn; /* active connection, if there is one */
|
|
int error; /* 1 if rpcap_remoteact_getsock got an error */
|
|
|
|
/*
|
|
* Determine the type of the source (NULL, file, local, remote).
|
|
* You must have a valid source string even if we're in active mode,
|
|
* because otherwise the call to the following function will fail.
|
|
*/
|
|
if (pcap_parsesrcstr_ex(source, &type, host, port, iface, uses_sslp,
|
|
errbuf) == -1)
|
|
return -1;
|
|
|
|
/*
|
|
* It must be remote.
|
|
*/
|
|
if (type != PCAP_SRC_IFREMOTE)
|
|
{
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
|
"Non-remote interface passed to remote capture routine");
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* We don't yet support DTLS, so if the user asks for a TLS
|
|
* connection and asks for data packets to be sent over UDP,
|
|
* we have to give up.
|
|
*/
|
|
if (*uses_sslp && (rmt_flags & PCAP_OPENFLAG_DATATX_UDP))
|
|
{
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
|
"TLS not supported with UDP forward of remote packets");
|
|
return -1;
|
|
}
|
|
|
|
/* Warning: this call can be the first one called by the user. */
|
|
/* For this reason, we have to initialize the Winsock support. */
|
|
if (sock_init(errbuf, PCAP_ERRBUF_SIZE) == -1)
|
|
return -1;
|
|
|
|
/* Check for active mode */
|
|
activeconn = rpcap_remoteact_getsock(host, &error, errbuf);
|
|
if (activeconn != NULL)
|
|
{
|
|
*activep = 1;
|
|
*sockctrlp = activeconn->sockctrl;
|
|
*sslp = activeconn->ssl;
|
|
*protocol_versionp = activeconn->protocol_version;
|
|
}
|
|
else
|
|
{
|
|
*activep = 0;
|
|
struct addrinfo hints; /* temp variable needed to resolve hostnames into to socket representation */
|
|
struct addrinfo *addrinfo; /* temp variable needed to resolve hostnames into to socket representation */
|
|
|
|
if (error)
|
|
{
|
|
/*
|
|
* Call failed.
|
|
*/
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* We're not in active mode; let's try to open a new
|
|
* control connection.
|
|
*/
|
|
memset(&hints, 0, sizeof(struct addrinfo));
|
|
hints.ai_family = PF_UNSPEC;
|
|
hints.ai_socktype = SOCK_STREAM;
|
|
|
|
if (port[0] == 0)
|
|
{
|
|
/* the user chose not to specify the port */
|
|
if (sock_initaddress(host, RPCAP_DEFAULT_NETPORT,
|
|
&hints, &addrinfo, errbuf, PCAP_ERRBUF_SIZE) == -1)
|
|
return -1;
|
|
}
|
|
else
|
|
{
|
|
if (sock_initaddress(host, port, &hints, &addrinfo,
|
|
errbuf, PCAP_ERRBUF_SIZE) == -1)
|
|
return -1;
|
|
}
|
|
|
|
if ((*sockctrlp = sock_open(addrinfo, SOCKOPEN_CLIENT, 0,
|
|
errbuf, PCAP_ERRBUF_SIZE)) == INVALID_SOCKET)
|
|
{
|
|
freeaddrinfo(addrinfo);
|
|
return -1;
|
|
}
|
|
|
|
/* addrinfo is no longer used */
|
|
freeaddrinfo(addrinfo);
|
|
addrinfo = NULL;
|
|
|
|
if (*uses_sslp)
|
|
{
|
|
#ifdef HAVE_OPENSSL
|
|
*sslp = ssl_promotion(0, *sockctrlp, errbuf,
|
|
PCAP_ERRBUF_SIZE);
|
|
if (!*sslp)
|
|
{
|
|
sock_close(*sockctrlp, NULL, 0);
|
|
return -1;
|
|
}
|
|
#else
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
|
"No TLS support");
|
|
sock_close(*sockctrlp, NULL, 0);
|
|
return -1;
|
|
#endif
|
|
}
|
|
|
|
if (rpcap_doauth(*sockctrlp, *sslp, protocol_versionp, auth,
|
|
errbuf) == -1)
|
|
{
|
|
#ifdef HAVE_OPENSSL
|
|
if (*sslp)
|
|
{
|
|
// Finish using the SSL handle for the socket.
|
|
// This must be done *before* the socket is
|
|
// closed.
|
|
ssl_finish(*sslp);
|
|
}
|
|
#endif
|
|
sock_close(*sockctrlp, NULL, 0);
|
|
return -1;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* This function opens a remote adapter by opening an RPCAP connection and
|
|
* so on.
|
|
*
|
|
* It does the job of pcap_open_live() for a remote interface; it's called
|
|
* by pcap_open() for remote interfaces.
|
|
*
|
|
* We do not start the capture until pcap_startcapture_remote() is called.
|
|
*
|
|
* This is because, when doing a remote capture, we cannot start capturing
|
|
* data as soon as the 'open adapter' command is sent. Suppose the remote
|
|
* adapter is already overloaded; if we start a capture (which, by default,
|
|
* has a NULL filter) the new traffic can saturate the network.
|
|
*
|
|
* Instead, we want to "open" the adapter, then send a "start capture"
|
|
* command only when we're ready to start the capture.
|
|
* This function does this job: it sends an "open adapter" command
|
|
* (according to the RPCAP protocol), but it does not start the capture.
|
|
*
|
|
* Since the other libpcap functions do not share this way of life, we
|
|
* have to do some dirty things in order to make everything work.
|
|
*
|
|
* \param source: see pcap_open().
|
|
* \param snaplen: see pcap_open().
|
|
* \param flags: see pcap_open().
|
|
* \param read_timeout: see pcap_open().
|
|
* \param auth: see pcap_open().
|
|
* \param errbuf: see pcap_open().
|
|
*
|
|
* \return a pcap_t pointer in case of success, NULL otherwise. In case of
|
|
* success, the pcap_t pointer can be used as a parameter to the following
|
|
* calls (pcap_compile() and so on). In case of problems, errbuf contains
|
|
* a text explanation of error.
|
|
*
|
|
* WARNING: In case we call pcap_compile() and the capture has not yet
|
|
* been started, the filter will be saved into the pcap_t structure,
|
|
* and it will be sent to the other host later (when
|
|
* pcap_startcapture_remote() is called).
|
|
*/
|
|
pcap_t *pcap_open_rpcap(const char *source, int snaplen, int flags, int read_timeout, struct pcap_rmtauth *auth, char *errbuf)
|
|
{
|
|
pcap_t *fp;
|
|
char *source_str;
|
|
struct pcap_rpcap *pr; /* structure used when doing a remote live capture */
|
|
char host[PCAP_BUF_SIZE], ctrlport[PCAP_BUF_SIZE], iface[PCAP_BUF_SIZE];
|
|
SOCKET sockctrl;
|
|
SSL *ssl = NULL;
|
|
uint8 protocol_version; /* negotiated protocol version */
|
|
int active;
|
|
uint32 plen;
|
|
char sendbuf[RPCAP_NETBUF_SIZE]; /* temporary buffer in which data to be sent is buffered */
|
|
int sendbufidx = 0; /* index which keeps the number of bytes currently buffered */
|
|
|
|
/* RPCAP-related variables */
|
|
struct rpcap_header header; /* header of the RPCAP packet */
|
|
struct rpcap_openreply openreply; /* open reply message */
|
|
|
|
fp = PCAP_CREATE_COMMON(errbuf, struct pcap_rpcap);
|
|
if (fp == NULL)
|
|
{
|
|
return NULL;
|
|
}
|
|
source_str = strdup(source);
|
|
if (source_str == NULL) {
|
|
pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
|
|
errno, "malloc");
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Turn a negative snapshot value (invalid), a snapshot value of
|
|
* 0 (unspecified), or a value bigger than the normal maximum
|
|
* value, into the maximum allowed value.
|
|
*
|
|
* If some application really *needs* a bigger snapshot
|
|
* length, we should just increase MAXIMUM_SNAPLEN.
|
|
*
|
|
* XXX - should we leave this up to the remote server to
|
|
* do?
|
|
*/
|
|
if (snaplen <= 0 || snaplen > MAXIMUM_SNAPLEN)
|
|
snaplen = MAXIMUM_SNAPLEN;
|
|
|
|
fp->opt.device = source_str;
|
|
fp->snapshot = snaplen;
|
|
fp->opt.timeout = read_timeout;
|
|
pr = fp->priv;
|
|
pr->rmt_flags = flags;
|
|
|
|
/*
|
|
* Attempt to set up the session with the server.
|
|
*/
|
|
if (rpcap_setup_session(fp->opt.device, auth, &active, &sockctrl,
|
|
&pr->uses_ssl, &ssl, flags, &protocol_version, host, ctrlport,
|
|
iface, errbuf) == -1)
|
|
{
|
|
/* Session setup failed. */
|
|
pcap_close(fp);
|
|
return NULL;
|
|
}
|
|
|
|
/* All good so far, save the ssl handler */
|
|
ssl_main = ssl;
|
|
|
|
/*
|
|
* Now it's time to start playing with the RPCAP protocol
|
|
* RPCAP open command: create the request message
|
|
*/
|
|
if (sock_bufferize(NULL, sizeof(struct rpcap_header), NULL,
|
|
&sendbufidx, RPCAP_NETBUF_SIZE, SOCKBUF_CHECKONLY, errbuf, PCAP_ERRBUF_SIZE))
|
|
goto error_nodiscard;
|
|
|
|
rpcap_createhdr((struct rpcap_header *) sendbuf, protocol_version,
|
|
RPCAP_MSG_OPEN_REQ, 0, (uint32) strlen(iface));
|
|
|
|
if (sock_bufferize(iface, (int) strlen(iface), sendbuf, &sendbufidx,
|
|
RPCAP_NETBUF_SIZE, SOCKBUF_BUFFERIZE, errbuf, PCAP_ERRBUF_SIZE))
|
|
goto error_nodiscard;
|
|
|
|
if (sock_send(sockctrl, ssl, sendbuf, sendbufidx, errbuf,
|
|
PCAP_ERRBUF_SIZE) < 0)
|
|
goto error_nodiscard;
|
|
|
|
/* Receive and process the reply message header. */
|
|
if (rpcap_process_msg_header(sockctrl, ssl, protocol_version,
|
|
RPCAP_MSG_OPEN_REQ, &header, errbuf) == -1)
|
|
goto error_nodiscard;
|
|
plen = header.plen;
|
|
|
|
/* Read the reply body */
|
|
if (rpcap_recv(sockctrl, ssl, (char *)&openreply,
|
|
sizeof(struct rpcap_openreply), &plen, errbuf) == -1)
|
|
goto error;
|
|
|
|
/* Discard the rest of the message, if there is any. */
|
|
if (rpcap_discard(sockctrl, ssl, plen, errbuf) == -1)
|
|
goto error_nodiscard;
|
|
|
|
/* Set proper fields into the pcap_t struct */
|
|
fp->linktype = ntohl(openreply.linktype);
|
|
pr->rmt_sockctrl = sockctrl;
|
|
pr->ctrl_ssl = ssl;
|
|
pr->protocol_version = protocol_version;
|
|
pr->rmt_clientside = 1;
|
|
|
|
/* This code is duplicated from the end of this function */
|
|
fp->read_op = pcap_read_rpcap;
|
|
fp->save_current_filter_op = pcap_save_current_filter_rpcap;
|
|
fp->setfilter_op = pcap_setfilter_rpcap;
|
|
fp->getnonblock_op = pcap_getnonblock_rpcap;
|
|
fp->setnonblock_op = pcap_setnonblock_rpcap;
|
|
fp->stats_op = pcap_stats_rpcap;
|
|
#ifdef _WIN32
|
|
fp->stats_ex_op = pcap_stats_ex_rpcap;
|
|
#endif
|
|
fp->cleanup_op = pcap_cleanup_rpcap;
|
|
|
|
fp->activated = 1;
|
|
return fp;
|
|
|
|
error:
|
|
/*
|
|
* When the connection has been established, we have to close it. So, at the
|
|
* beginning of this function, if an error occur we return immediately with
|
|
* a return NULL; when the connection is established, we have to come here
|
|
* ('goto error;') in order to close everything properly.
|
|
*/
|
|
|
|
/*
|
|
* Discard the rest of the message.
|
|
* We already reported an error; if this gets an error, just
|
|
* drive on.
|
|
*/
|
|
(void)rpcap_discard(sockctrl, pr->ctrl_ssl, plen, NULL);
|
|
|
|
error_nodiscard:
|
|
if (!active)
|
|
{
|
|
#ifdef HAVE_OPENSSL
|
|
if (ssl)
|
|
{
|
|
// Finish using the SSL handle for the socket.
|
|
// This must be done *before* the socket is closed.
|
|
ssl_finish(ssl);
|
|
}
|
|
#endif
|
|
sock_close(sockctrl, NULL, 0);
|
|
}
|
|
|
|
pcap_close(fp);
|
|
return NULL;
|
|
}
|
|
|
|
/* String identifier to be used in the pcap_findalldevs_ex() */
|
|
#define PCAP_TEXT_SOURCE_ADAPTER "Network adapter"
|
|
#define PCAP_TEXT_SOURCE_ADAPTER_LEN (sizeof PCAP_TEXT_SOURCE_ADAPTER - 1)
|
|
/* String identifier to be used in the pcap_findalldevs_ex() */
|
|
#define PCAP_TEXT_SOURCE_ON_REMOTE_HOST "on remote node"
|
|
#define PCAP_TEXT_SOURCE_ON_REMOTE_HOST_LEN (sizeof PCAP_TEXT_SOURCE_ON_REMOTE_HOST - 1)
|
|
|
|
static void
|
|
freeaddr(struct pcap_addr *addr)
|
|
{
|
|
free(addr->addr);
|
|
free(addr->netmask);
|
|
free(addr->broadaddr);
|
|
free(addr->dstaddr);
|
|
free(addr);
|
|
}
|
|
|
|
int
|
|
pcap_findalldevs_ex_remote(const char *source, struct pcap_rmtauth *auth, pcap_if_t **alldevs, char *errbuf)
|
|
{
|
|
uint8 protocol_version; /* protocol version */
|
|
SOCKET sockctrl; /* socket descriptor of the control connection */
|
|
SSL *ssl = NULL; /* optional SSL handler for sockctrl */
|
|
uint32 plen;
|
|
struct rpcap_header header; /* structure that keeps the general header of the rpcap protocol */
|
|
int i, j; /* temp variables */
|
|
int nif; /* Number of interfaces listed */
|
|
int active; /* 'true' if we the other end-party is in active mode */
|
|
uint8 uses_ssl;
|
|
char host[PCAP_BUF_SIZE], port[PCAP_BUF_SIZE];
|
|
char tmpstring[PCAP_BUF_SIZE + 1]; /* Needed to convert names and descriptions from 'old' syntax to the 'new' one */
|
|
pcap_if_t *lastdev; /* Last device in the pcap_if_t list */
|
|
pcap_if_t *dev; /* Device we're adding to the pcap_if_t list */
|
|
|
|
/* List starts out empty. */
|
|
(*alldevs) = NULL;
|
|
lastdev = NULL;
|
|
|
|
/*
|
|
* Attempt to set up the session with the server.
|
|
*/
|
|
if (rpcap_setup_session(source, auth, &active, &sockctrl, &uses_ssl,
|
|
&ssl, 0, &protocol_version, host, port, NULL, errbuf) == -1)
|
|
{
|
|
/* Session setup failed. */
|
|
return -1;
|
|
}
|
|
|
|
/* RPCAP findalldevs command */
|
|
rpcap_createhdr(&header, protocol_version, RPCAP_MSG_FINDALLIF_REQ,
|
|
0, 0);
|
|
|
|
if (sock_send(sockctrl, ssl, (char *)&header, sizeof(struct rpcap_header),
|
|
errbuf, PCAP_ERRBUF_SIZE) < 0)
|
|
goto error_nodiscard;
|
|
|
|
/* Receive and process the reply message header. */
|
|
if (rpcap_process_msg_header(sockctrl, ssl, protocol_version,
|
|
RPCAP_MSG_FINDALLIF_REQ, &header, errbuf) == -1)
|
|
goto error_nodiscard;
|
|
|
|
plen = header.plen;
|
|
|
|
/* read the number of interfaces */
|
|
nif = ntohs(header.value);
|
|
|
|
/* loop until all interfaces have been received */
|
|
for (i = 0; i < nif; i++)
|
|
{
|
|
struct rpcap_findalldevs_if findalldevs_if;
|
|
char tmpstring2[PCAP_BUF_SIZE + 1]; /* Needed to convert names and descriptions from 'old' syntax to the 'new' one */
|
|
struct pcap_addr *addr, *prevaddr;
|
|
|
|
tmpstring2[PCAP_BUF_SIZE] = 0;
|
|
|
|
/* receive the findalldevs structure from remote host */
|
|
if (rpcap_recv(sockctrl, ssl, (char *)&findalldevs_if,
|
|
sizeof(struct rpcap_findalldevs_if), &plen, errbuf) == -1)
|
|
goto error;
|
|
|
|
findalldevs_if.namelen = ntohs(findalldevs_if.namelen);
|
|
findalldevs_if.desclen = ntohs(findalldevs_if.desclen);
|
|
findalldevs_if.naddr = ntohs(findalldevs_if.naddr);
|
|
|
|
/* allocate the main structure */
|
|
dev = (pcap_if_t *)malloc(sizeof(pcap_if_t));
|
|
if (dev == NULL)
|
|
{
|
|
pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
|
|
errno, "malloc() failed");
|
|
goto error;
|
|
}
|
|
|
|
/* Initialize the structure to 'zero' */
|
|
memset(dev, 0, sizeof(pcap_if_t));
|
|
|
|
/* Append it to the list. */
|
|
if (lastdev == NULL)
|
|
{
|
|
/*
|
|
* List is empty, so it's also the first device.
|
|
*/
|
|
*alldevs = dev;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Append after the last device.
|
|
*/
|
|
lastdev->next = dev;
|
|
}
|
|
/* It's now the last device. */
|
|
lastdev = dev;
|
|
|
|
/* allocate mem for name and description */
|
|
if (findalldevs_if.namelen)
|
|
{
|
|
|
|
if (findalldevs_if.namelen >= sizeof(tmpstring))
|
|
{
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "Interface name too long");
|
|
goto error;
|
|
}
|
|
|
|
/* Retrieve adapter name */
|
|
if (rpcap_recv(sockctrl, ssl, tmpstring,
|
|
findalldevs_if.namelen, &plen, errbuf) == -1)
|
|
goto error;
|
|
|
|
tmpstring[findalldevs_if.namelen] = 0;
|
|
|
|
/* Create the new device identifier */
|
|
if (pcap_createsrcstr_ex(tmpstring2, PCAP_SRC_IFREMOTE,
|
|
host, port, tmpstring, uses_ssl, errbuf) == -1)
|
|
goto error;
|
|
|
|
dev->name = strdup(tmpstring2);
|
|
if (dev->name == NULL)
|
|
{
|
|
pcap_fmt_errmsg_for_errno(errbuf,
|
|
PCAP_ERRBUF_SIZE, errno, "malloc() failed");
|
|
goto error;
|
|
}
|
|
}
|
|
|
|
if (findalldevs_if.desclen)
|
|
{
|
|
if (findalldevs_if.desclen >= sizeof(tmpstring))
|
|
{
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "Interface description too long");
|
|
goto error;
|
|
}
|
|
|
|
/* Retrieve adapter description */
|
|
if (rpcap_recv(sockctrl, ssl, tmpstring,
|
|
findalldevs_if.desclen, &plen, errbuf) == -1)
|
|
goto error;
|
|
|
|
tmpstring[findalldevs_if.desclen] = 0;
|
|
|
|
if (pcap_asprintf(&dev->description,
|
|
"%s '%s' %s %s", PCAP_TEXT_SOURCE_ADAPTER,
|
|
tmpstring, PCAP_TEXT_SOURCE_ON_REMOTE_HOST, host) == -1)
|
|
{
|
|
pcap_fmt_errmsg_for_errno(errbuf,
|
|
PCAP_ERRBUF_SIZE, errno, "malloc() failed");
|
|
goto error;
|
|
}
|
|
}
|
|
|
|
dev->flags = ntohl(findalldevs_if.flags);
|
|
|
|
prevaddr = NULL;
|
|
/* loop until all addresses have been received */
|
|
for (j = 0; j < findalldevs_if.naddr; j++)
|
|
{
|
|
struct rpcap_findalldevs_ifaddr ifaddr;
|
|
|
|
/* Retrieve the interface addresses */
|
|
if (rpcap_recv(sockctrl, ssl, (char *)&ifaddr,
|
|
sizeof(struct rpcap_findalldevs_ifaddr),
|
|
&plen, errbuf) == -1)
|
|
goto error;
|
|
|
|
/*
|
|
* Deserialize all the address components.
|
|
*/
|
|
addr = (struct pcap_addr *) malloc(sizeof(struct pcap_addr));
|
|
if (addr == NULL)
|
|
{
|
|
pcap_fmt_errmsg_for_errno(errbuf,
|
|
PCAP_ERRBUF_SIZE, errno, "malloc() failed");
|
|
goto error;
|
|
}
|
|
addr->next = NULL;
|
|
addr->addr = NULL;
|
|
addr->netmask = NULL;
|
|
addr->broadaddr = NULL;
|
|
addr->dstaddr = NULL;
|
|
|
|
if (rpcap_deseraddr(&ifaddr.addr,
|
|
(struct sockaddr_storage **) &addr->addr, errbuf) == -1)
|
|
{
|
|
freeaddr(addr);
|
|
goto error;
|
|
}
|
|
if (rpcap_deseraddr(&ifaddr.netmask,
|
|
(struct sockaddr_storage **) &addr->netmask, errbuf) == -1)
|
|
{
|
|
freeaddr(addr);
|
|
goto error;
|
|
}
|
|
if (rpcap_deseraddr(&ifaddr.broadaddr,
|
|
(struct sockaddr_storage **) &addr->broadaddr, errbuf) == -1)
|
|
{
|
|
freeaddr(addr);
|
|
goto error;
|
|
}
|
|
if (rpcap_deseraddr(&ifaddr.dstaddr,
|
|
(struct sockaddr_storage **) &addr->dstaddr, errbuf) == -1)
|
|
{
|
|
freeaddr(addr);
|
|
goto error;
|
|
}
|
|
|
|
if ((addr->addr == NULL) && (addr->netmask == NULL) &&
|
|
(addr->broadaddr == NULL) && (addr->dstaddr == NULL))
|
|
{
|
|
/*
|
|
* None of the addresses are IPv4 or IPv6
|
|
* addresses, so throw this entry away.
|
|
*/
|
|
free(addr);
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Add this entry to the list.
|
|
*/
|
|
if (prevaddr == NULL)
|
|
{
|
|
dev->addresses = addr;
|
|
}
|
|
else
|
|
{
|
|
prevaddr->next = addr;
|
|
}
|
|
prevaddr = addr;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Discard the rest of the message. */
|
|
if (rpcap_discard(sockctrl, ssl, plen, errbuf) == 1)
|
|
goto error_nodiscard;
|
|
|
|
/* Control connection has to be closed only in case the remote machine is in passive mode */
|
|
if (!active)
|
|
{
|
|
/* DO not send RPCAP_CLOSE, since we did not open a pcap_t; no need to free resources */
|
|
#ifdef HAVE_OPENSSL
|
|
if (ssl)
|
|
{
|
|
// Finish using the SSL handle for the socket.
|
|
// This must be done *before* the socket is closed.
|
|
ssl_finish(ssl);
|
|
}
|
|
#endif
|
|
if (sock_close(sockctrl, errbuf, PCAP_ERRBUF_SIZE))
|
|
return -1;
|
|
}
|
|
|
|
/* To avoid inconsistencies in the number of sock_init() */
|
|
sock_cleanup();
|
|
|
|
return 0;
|
|
|
|
error:
|
|
/*
|
|
* In case there has been an error, I don't want to overwrite it with a new one
|
|
* if the following call fails. I want to return always the original error.
|
|
*
|
|
* Take care: this connection can already be closed when we try to close it.
|
|
* This happens because a previous error in the rpcapd, which requested to
|
|
* closed the connection. In that case, we already recognized that into the
|
|
* rpspck_isheaderok() and we already acknowledged the closing.
|
|
* In that sense, this call is useless here (however it is needed in case
|
|
* the client generates the error).
|
|
*
|
|
* Checks if all the data has been read; if not, discard the data in excess
|
|
*/
|
|
(void) rpcap_discard(sockctrl, ssl, plen, NULL);
|
|
|
|
error_nodiscard:
|
|
/* Control connection has to be closed only in case the remote machine is in passive mode */
|
|
if (!active)
|
|
{
|
|
#ifdef HAVE_OPENSSL
|
|
if (ssl)
|
|
{
|
|
// Finish using the SSL handle for the socket.
|
|
// This must be done *before* the socket is closed.
|
|
ssl_finish(ssl);
|
|
}
|
|
#endif
|
|
sock_close(sockctrl, NULL, 0);
|
|
}
|
|
|
|
/* To avoid inconsistencies in the number of sock_init() */
|
|
sock_cleanup();
|
|
|
|
/* Free whatever interfaces we've allocated. */
|
|
pcap_freealldevs(*alldevs);
|
|
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Active mode routines.
|
|
*
|
|
* The old libpcap API is somewhat ugly, and makes active mode difficult
|
|
* to implement; we provide some APIs for it that work only with rpcap.
|
|
*/
|
|
|
|
SOCKET pcap_remoteact_accept_ex(const char *address, const char *port, const char *hostlist, char *connectinghost, struct pcap_rmtauth *auth, int uses_ssl, char *errbuf)
|
|
{
|
|
/* socket-related variables */
|
|
struct addrinfo hints; /* temporary struct to keep settings needed to open the new socket */
|
|
struct addrinfo *addrinfo; /* keeps the addrinfo chain; required to open a new socket */
|
|
struct sockaddr_storage from; /* generic sockaddr_storage variable */
|
|
socklen_t fromlen; /* keeps the length of the sockaddr_storage variable */
|
|
SOCKET sockctrl; /* keeps the main socket identifier */
|
|
SSL *ssl = NULL; /* Optional SSL handler for sockctrl */
|
|
uint8 protocol_version; /* negotiated protocol version */
|
|
struct activehosts *temp, *prev; /* temp var needed to scan he host list chain */
|
|
|
|
*connectinghost = 0; /* just in case */
|
|
|
|
/* Prepare to open a new server socket */
|
|
memset(&hints, 0, sizeof(struct addrinfo));
|
|
/* WARNING Currently it supports only ONE socket family among ipv4 and IPv6 */
|
|
hints.ai_family = AF_INET; /* PF_UNSPEC to have both IPv4 and IPv6 server */
|
|
hints.ai_flags = AI_PASSIVE; /* Ready to a bind() socket */
|
|
hints.ai_socktype = SOCK_STREAM;
|
|
|
|
/* Warning: this call can be the first one called by the user. */
|
|
/* For this reason, we have to initialize the Winsock support. */
|
|
if (sock_init(errbuf, PCAP_ERRBUF_SIZE) == -1)
|
|
return (SOCKET)-1;
|
|
|
|
/* Do the work */
|
|
if ((port == NULL) || (port[0] == 0))
|
|
{
|
|
if (sock_initaddress(address, RPCAP_DEFAULT_NETPORT_ACTIVE, &hints, &addrinfo, errbuf, PCAP_ERRBUF_SIZE) == -1)
|
|
{
|
|
return (SOCKET)-2;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (sock_initaddress(address, port, &hints, &addrinfo, errbuf, PCAP_ERRBUF_SIZE) == -1)
|
|
{
|
|
return (SOCKET)-2;
|
|
}
|
|
}
|
|
|
|
|
|
if ((sockmain = sock_open(addrinfo, SOCKOPEN_SERVER, 1, errbuf, PCAP_ERRBUF_SIZE)) == INVALID_SOCKET)
|
|
{
|
|
freeaddrinfo(addrinfo);
|
|
return (SOCKET)-2;
|
|
}
|
|
freeaddrinfo(addrinfo);
|
|
|
|
/* Connection creation */
|
|
fromlen = sizeof(struct sockaddr_storage);
|
|
|
|
sockctrl = accept(sockmain, (struct sockaddr *) &from, &fromlen);
|
|
|
|
/* We're not using sock_close, since we do not want to send a shutdown */
|
|
/* (which is not allowed on a non-connected socket) */
|
|
closesocket(sockmain);
|
|
sockmain = 0;
|
|
|
|
if (sockctrl == INVALID_SOCKET)
|
|
{
|
|
sock_geterror("accept()", errbuf, PCAP_ERRBUF_SIZE);
|
|
return (SOCKET)-2;
|
|
}
|
|
|
|
/* Promote to SSL early before any error message may be sent */
|
|
if (uses_ssl)
|
|
{
|
|
#ifdef HAVE_OPENSSL
|
|
ssl = ssl_promotion(0, sockctrl, errbuf, PCAP_ERRBUF_SIZE);
|
|
if (! ssl)
|
|
{
|
|
sock_close(sockctrl, NULL, 0);
|
|
return (SOCKET)-1;
|
|
}
|
|
#else
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "No TLS support");
|
|
sock_close(sockctrl, NULL, 0);
|
|
return (SOCKET)-1;
|
|
#endif
|
|
}
|
|
|
|
/* Get the numeric for of the name of the connecting host */
|
|
if (getnameinfo((struct sockaddr *) &from, fromlen, connectinghost, RPCAP_HOSTLIST_SIZE, NULL, 0, NI_NUMERICHOST))
|
|
{
|
|
sock_geterror("getnameinfo()", errbuf, PCAP_ERRBUF_SIZE);
|
|
rpcap_senderror(sockctrl, ssl, 0, PCAP_ERR_REMOTEACCEPT, errbuf, NULL);
|
|
#ifdef HAVE_OPENSSL
|
|
if (ssl)
|
|
{
|
|
// Finish using the SSL handle for the socket.
|
|
// This must be done *before* the socket is closed.
|
|
ssl_finish(ssl);
|
|
}
|
|
#endif
|
|
sock_close(sockctrl, NULL, 0);
|
|
return (SOCKET)-1;
|
|
}
|
|
|
|
/* checks if the connecting host is among the ones allowed */
|
|
if (sock_check_hostlist((char *)hostlist, RPCAP_HOSTLIST_SEP, &from, errbuf, PCAP_ERRBUF_SIZE) < 0)
|
|
{
|
|
rpcap_senderror(sockctrl, ssl, 0, PCAP_ERR_REMOTEACCEPT, errbuf, NULL);
|
|
#ifdef HAVE_OPENSSL
|
|
if (ssl)
|
|
{
|
|
// Finish using the SSL handle for the socket.
|
|
// This must be done *before* the socket is closed.
|
|
ssl_finish(ssl);
|
|
}
|
|
#endif
|
|
sock_close(sockctrl, NULL, 0);
|
|
return (SOCKET)-1;
|
|
}
|
|
|
|
/*
|
|
* Send authentication to the remote machine.
|
|
*/
|
|
if (rpcap_doauth(sockctrl, ssl, &protocol_version, auth, errbuf) == -1)
|
|
{
|
|
/* Unrecoverable error. */
|
|
rpcap_senderror(sockctrl, ssl, 0, PCAP_ERR_REMOTEACCEPT, errbuf, NULL);
|
|
#ifdef HAVE_OPENSSL
|
|
if (ssl)
|
|
{
|
|
// Finish using the SSL handle for the socket.
|
|
// This must be done *before* the socket is closed.
|
|
ssl_finish(ssl);
|
|
}
|
|
#endif
|
|
sock_close(sockctrl, NULL, 0);
|
|
return (SOCKET)-3;
|
|
}
|
|
|
|
/* Checks that this host does not already have a cntrl connection in place */
|
|
|
|
/* Initialize pointers */
|
|
temp = activeHosts;
|
|
prev = NULL;
|
|
|
|
while (temp)
|
|
{
|
|
/* This host already has an active connection in place, so I don't have to update the host list */
|
|
if (sock_cmpaddr(&temp->host, &from) == 0)
|
|
return sockctrl;
|
|
|
|
prev = temp;
|
|
temp = temp->next;
|
|
}
|
|
|
|
/* The host does not exist in the list; so I have to update the list */
|
|
if (prev)
|
|
{
|
|
prev->next = (struct activehosts *) malloc(sizeof(struct activehosts));
|
|
temp = prev->next;
|
|
}
|
|
else
|
|
{
|
|
activeHosts = (struct activehosts *) malloc(sizeof(struct activehosts));
|
|
temp = activeHosts;
|
|
}
|
|
|
|
if (temp == NULL)
|
|
{
|
|
pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
|
|
errno, "malloc() failed");
|
|
rpcap_senderror(sockctrl, ssl, protocol_version, PCAP_ERR_REMOTEACCEPT, errbuf, NULL);
|
|
#ifdef HAVE_OPENSSL
|
|
if (ssl)
|
|
{
|
|
// Finish using the SSL handle for the socket.
|
|
// This must be done *before* the socket is closed.
|
|
ssl_finish(ssl);
|
|
}
|
|
#endif
|
|
sock_close(sockctrl, NULL, 0);
|
|
return (SOCKET)-1;
|
|
}
|
|
|
|
memcpy(&temp->host, &from, fromlen);
|
|
temp->sockctrl = sockctrl;
|
|
temp->ssl = ssl;
|
|
temp->protocol_version = protocol_version;
|
|
temp->next = NULL;
|
|
|
|
return sockctrl;
|
|
}
|
|
|
|
SOCKET pcap_remoteact_accept(const char *address, const char *port, const char *hostlist, char *connectinghost, struct pcap_rmtauth *auth, char *errbuf)
|
|
{
|
|
return pcap_remoteact_accept_ex(address, port, hostlist, connectinghost, auth, 0, errbuf);
|
|
}
|
|
|
|
int pcap_remoteact_close(const char *host, char *errbuf)
|
|
{
|
|
struct activehosts *temp, *prev; /* temp var needed to scan the host list chain */
|
|
struct addrinfo hints, *addrinfo, *ai_next; /* temp var needed to translate between hostname to its address */
|
|
int retval;
|
|
|
|
temp = activeHosts;
|
|
prev = NULL;
|
|
|
|
/* retrieve the network address corresponding to 'host' */
|
|
addrinfo = NULL;
|
|
memset(&hints, 0, sizeof(struct addrinfo));
|
|
hints.ai_family = PF_UNSPEC;
|
|
hints.ai_socktype = SOCK_STREAM;
|
|
|
|
retval = getaddrinfo(host, "0", &hints, &addrinfo);
|
|
if (retval != 0)
|
|
{
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "getaddrinfo() %s", gai_strerror(retval));
|
|
return -1;
|
|
}
|
|
|
|
while (temp)
|
|
{
|
|
ai_next = addrinfo;
|
|
while (ai_next)
|
|
{
|
|
if (sock_cmpaddr(&temp->host, (struct sockaddr_storage *) ai_next->ai_addr) == 0)
|
|
{
|
|
struct rpcap_header header;
|
|
int status = 0;
|
|
|
|
/* Close this connection */
|
|
rpcap_createhdr(&header, temp->protocol_version,
|
|
RPCAP_MSG_CLOSE, 0, 0);
|
|
|
|
/*
|
|
* Don't check for errors, since we're
|
|
* just cleaning up.
|
|
*/
|
|
if (sock_send(temp->sockctrl, temp->ssl,
|
|
(char *)&header,
|
|
sizeof(struct rpcap_header), errbuf,
|
|
PCAP_ERRBUF_SIZE) < 0)
|
|
{
|
|
/*
|
|
* Let that error be the one we
|
|
* report.
|
|
*/
|
|
#ifdef HAVE_OPENSSL
|
|
if (temp->ssl)
|
|
{
|
|
// Finish using the SSL handle
|
|
// for the socket.
|
|
// This must be done *before*
|
|
// the socket is closed.
|
|
ssl_finish(temp->ssl);
|
|
}
|
|
#endif
|
|
(void)sock_close(temp->sockctrl, NULL,
|
|
0);
|
|
status = -1;
|
|
}
|
|
else
|
|
{
|
|
#ifdef HAVE_OPENSSL
|
|
if (temp->ssl)
|
|
{
|
|
// Finish using the SSL handle
|
|
// for the socket.
|
|
// This must be done *before*
|
|
// the socket is closed.
|
|
ssl_finish(temp->ssl);
|
|
}
|
|
#endif
|
|
if (sock_close(temp->sockctrl, errbuf,
|
|
PCAP_ERRBUF_SIZE) == -1)
|
|
status = -1;
|
|
}
|
|
|
|
/*
|
|
* Remove the host from the list of active
|
|
* hosts.
|
|
*/
|
|
if (prev)
|
|
prev->next = temp->next;
|
|
else
|
|
activeHosts = temp->next;
|
|
|
|
freeaddrinfo(addrinfo);
|
|
|
|
free(temp);
|
|
|
|
/* To avoid inconsistencies in the number of sock_init() */
|
|
sock_cleanup();
|
|
|
|
return status;
|
|
}
|
|
|
|
ai_next = ai_next->ai_next;
|
|
}
|
|
prev = temp;
|
|
temp = temp->next;
|
|
}
|
|
|
|
if (addrinfo)
|
|
freeaddrinfo(addrinfo);
|
|
|
|
/* To avoid inconsistencies in the number of sock_init() */
|
|
sock_cleanup();
|
|
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "The host you want to close the active connection is not known");
|
|
return -1;
|
|
}
|
|
|
|
void pcap_remoteact_cleanup(void)
|
|
{
|
|
# ifdef HAVE_OPENSSL
|
|
if (ssl_main)
|
|
{
|
|
// Finish using the SSL handle for the main active socket.
|
|
// This must be done *before* the socket is closed.
|
|
ssl_finish(ssl_main);
|
|
ssl_main = NULL;
|
|
}
|
|
# endif
|
|
|
|
/* Very dirty, but it works */
|
|
if (sockmain)
|
|
{
|
|
closesocket(sockmain);
|
|
|
|
/* To avoid inconsistencies in the number of sock_init() */
|
|
sock_cleanup();
|
|
}
|
|
}
|
|
|
|
int pcap_remoteact_list(char *hostlist, char sep, int size, char *errbuf)
|
|
{
|
|
struct activehosts *temp; /* temp var needed to scan the host list chain */
|
|
size_t len;
|
|
char hoststr[RPCAP_HOSTLIST_SIZE + 1];
|
|
|
|
temp = activeHosts;
|
|
|
|
len = 0;
|
|
*hostlist = 0;
|
|
|
|
while (temp)
|
|
{
|
|
/*int sock_getascii_addrport(const struct sockaddr_storage *sockaddr, char *address, int addrlen, char *port, int portlen, int flags, char *errbuf, int errbuflen) */
|
|
|
|
/* Get the numeric form of the name of the connecting host */
|
|
if (sock_getascii_addrport((struct sockaddr_storage *) &temp->host, hoststr,
|
|
RPCAP_HOSTLIST_SIZE, NULL, 0, NI_NUMERICHOST, errbuf, PCAP_ERRBUF_SIZE) != -1)
|
|
/* if (getnameinfo( (struct sockaddr *) &temp->host, sizeof (struct sockaddr_storage), hoststr, */
|
|
/* RPCAP_HOSTLIST_SIZE, NULL, 0, NI_NUMERICHOST) ) */
|
|
{
|
|
/* sock_geterror("getnameinfo()", errbuf, PCAP_ERRBUF_SIZE); */
|
|
return -1;
|
|
}
|
|
|
|
len = len + strlen(hoststr) + 1 /* the separator */;
|
|
|
|
if ((size < 0) || (len >= (size_t)size))
|
|
{
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "The string you provided is not able to keep "
|
|
"the hostnames for all the active connections");
|
|
return -1;
|
|
}
|
|
|
|
pcap_strlcat(hostlist, hoststr, PCAP_ERRBUF_SIZE);
|
|
hostlist[len - 1] = sep;
|
|
hostlist[len] = 0;
|
|
|
|
temp = temp->next;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Receive the header of a message.
|
|
*/
|
|
static int rpcap_recv_msg_header(SOCKET sock, SSL *ssl, struct rpcap_header *header, char *errbuf)
|
|
{
|
|
int nrecv;
|
|
|
|
nrecv = sock_recv(sock, ssl, (char *) header, sizeof(struct rpcap_header),
|
|
SOCK_RECEIVEALL_YES|SOCK_EOF_IS_ERROR, errbuf,
|
|
PCAP_ERRBUF_SIZE);
|
|
if (nrecv == -1)
|
|
{
|
|
/* Network error. */
|
|
return -1;
|
|
}
|
|
header->plen = ntohl(header->plen);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Make sure the protocol version of a received message is what we were
|
|
* expecting.
|
|
*/
|
|
static int rpcap_check_msg_ver(SOCKET sock, SSL *ssl, uint8 expected_ver, struct rpcap_header *header, char *errbuf)
|
|
{
|
|
/*
|
|
* Did the server specify the version we negotiated?
|
|
*/
|
|
if (header->ver != expected_ver)
|
|
{
|
|
/*
|
|
* Discard the rest of the message.
|
|
*/
|
|
if (rpcap_discard(sock, ssl, header->plen, errbuf) == -1)
|
|
return -1;
|
|
|
|
/*
|
|
* Tell our caller that it's not the negotiated version.
|
|
*/
|
|
if (errbuf != NULL)
|
|
{
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
|
"Server sent us a message with version %u when we were expecting %u",
|
|
header->ver, expected_ver);
|
|
}
|
|
return -1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Check the message type of a received message, which should either be
|
|
* the expected message type or RPCAP_MSG_ERROR.
|
|
*/
|
|
static int rpcap_check_msg_type(SOCKET sock, SSL *ssl, uint8 request_type, struct rpcap_header *header, uint16 *errcode, char *errbuf)
|
|
{
|
|
const char *request_type_string;
|
|
const char *msg_type_string;
|
|
|
|
/*
|
|
* What type of message is it?
|
|
*/
|
|
if (header->type == RPCAP_MSG_ERROR)
|
|
{
|
|
/*
|
|
* The server reported an error.
|
|
* Hand that error back to our caller.
|
|
*/
|
|
*errcode = ntohs(header->value);
|
|
rpcap_msg_err(sock, ssl, header->plen, errbuf);
|
|
return -1;
|
|
}
|
|
|
|
*errcode = 0;
|
|
|
|
/*
|
|
* For a given request type value, the expected reply type value
|
|
* is the request type value with ORed with RPCAP_MSG_IS_REPLY.
|
|
*/
|
|
if (header->type != (request_type | RPCAP_MSG_IS_REPLY))
|
|
{
|
|
/*
|
|
* This isn't a reply to the request we sent.
|
|
*/
|
|
|
|
/*
|
|
* Discard the rest of the message.
|
|
*/
|
|
if (rpcap_discard(sock, ssl, header->plen, errbuf) == -1)
|
|
return -1;
|
|
|
|
/*
|
|
* Tell our caller about it.
|
|
*/
|
|
request_type_string = rpcap_msg_type_string(request_type);
|
|
msg_type_string = rpcap_msg_type_string(header->type);
|
|
if (errbuf != NULL)
|
|
{
|
|
if (request_type_string == NULL)
|
|
{
|
|
/* This should not happen. */
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
|
"rpcap_check_msg_type called for request message with type %u",
|
|
request_type);
|
|
return -1;
|
|
}
|
|
if (msg_type_string != NULL)
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
|
"%s message received in response to a %s message",
|
|
msg_type_string, request_type_string);
|
|
else
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
|
"Message of unknown type %u message received in response to a %s request",
|
|
header->type, request_type_string);
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Receive and process the header of a message.
|
|
*/
|
|
static int rpcap_process_msg_header(SOCKET sock, SSL *ssl, uint8 expected_ver, uint8 request_type, struct rpcap_header *header, char *errbuf)
|
|
{
|
|
uint16 errcode;
|
|
|
|
if (rpcap_recv_msg_header(sock, ssl, header, errbuf) == -1)
|
|
{
|
|
/* Network error. */
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Did the server specify the version we negotiated?
|
|
*/
|
|
if (rpcap_check_msg_ver(sock, ssl, expected_ver, header, errbuf) == -1)
|
|
return -1;
|
|
|
|
/*
|
|
* Check the message type.
|
|
*/
|
|
return rpcap_check_msg_type(sock, ssl, request_type, header,
|
|
&errcode, errbuf);
|
|
}
|
|
|
|
/*
|
|
* Read data from a message.
|
|
* If we're trying to read more data that remains, puts an error
|
|
* message into errmsgbuf and returns -2. Otherwise, tries to read
|
|
* the data and, if that succeeds, subtracts the amount read from
|
|
* the number of bytes of data that remains.
|
|
* Returns 0 on success, logs a message and returns -1 on a network
|
|
* error.
|
|
*/
|
|
static int rpcap_recv(SOCKET sock, SSL *ssl, void *buffer, size_t toread, uint32 *plen, char *errbuf)
|
|
{
|
|
int nread;
|
|
|
|
if (toread > *plen)
|
|
{
|
|
/* The server sent us a bad message */
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "Message payload is too short");
|
|
return -1;
|
|
}
|
|
nread = sock_recv(sock, ssl, buffer, toread,
|
|
SOCK_RECEIVEALL_YES|SOCK_EOF_IS_ERROR, errbuf, PCAP_ERRBUF_SIZE);
|
|
if (nread == -1)
|
|
{
|
|
return -1;
|
|
}
|
|
*plen -= nread;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* This handles the RPCAP_MSG_ERROR message.
|
|
*/
|
|
static void rpcap_msg_err(SOCKET sockctrl, SSL *ssl, uint32 plen, char *remote_errbuf)
|
|
{
|
|
char errbuf[PCAP_ERRBUF_SIZE];
|
|
|
|
if (plen >= PCAP_ERRBUF_SIZE)
|
|
{
|
|
/*
|
|
* Message is too long; just read as much of it as we
|
|
* can into the buffer provided, and discard the rest.
|
|
*/
|
|
if (sock_recv(sockctrl, ssl, remote_errbuf, PCAP_ERRBUF_SIZE - 1,
|
|
SOCK_RECEIVEALL_YES|SOCK_EOF_IS_ERROR, errbuf,
|
|
PCAP_ERRBUF_SIZE) == -1)
|
|
{
|
|
// Network error.
|
|
snprintf(remote_errbuf, PCAP_ERRBUF_SIZE, "Read of error message from client failed: %s", errbuf);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Null-terminate it.
|
|
*/
|
|
remote_errbuf[PCAP_ERRBUF_SIZE - 1] = '\0';
|
|
|
|
#ifdef _WIN32
|
|
/*
|
|
* If we're not in UTF-8 mode, convert it to the local
|
|
* code page.
|
|
*/
|
|
if (!pcap_utf_8_mode)
|
|
utf_8_to_acp_truncated(remote_errbuf);
|
|
#endif
|
|
|
|
/*
|
|
* Throw away the rest.
|
|
*/
|
|
(void)rpcap_discard(sockctrl, ssl, plen - (PCAP_ERRBUF_SIZE - 1), remote_errbuf);
|
|
}
|
|
else if (plen == 0)
|
|
{
|
|
/* Empty error string. */
|
|
remote_errbuf[0] = '\0';
|
|
}
|
|
else
|
|
{
|
|
if (sock_recv(sockctrl, ssl, remote_errbuf, plen,
|
|
SOCK_RECEIVEALL_YES|SOCK_EOF_IS_ERROR, errbuf,
|
|
PCAP_ERRBUF_SIZE) == -1)
|
|
{
|
|
// Network error.
|
|
snprintf(remote_errbuf, PCAP_ERRBUF_SIZE, "Read of error message from client failed: %s", errbuf);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Null-terminate it.
|
|
*/
|
|
remote_errbuf[plen] = '\0';
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Discard data from a connection.
|
|
* Mostly used to discard wrong-sized messages.
|
|
* Returns 0 on success, logs a message and returns -1 on a network
|
|
* error.
|
|
*/
|
|
static int rpcap_discard(SOCKET sock, SSL *ssl, uint32 len, char *errbuf)
|
|
{
|
|
if (len != 0)
|
|
{
|
|
if (sock_discard(sock, ssl, len, errbuf, PCAP_ERRBUF_SIZE) == -1)
|
|
{
|
|
// Network error.
|
|
return -1;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Read bytes into the pcap_t's buffer until we have the specified
|
|
* number of bytes read or we get an error or interrupt indication.
|
|
*/
|
|
static int rpcap_read_packet_msg(struct pcap_rpcap const *rp, pcap_t *p, size_t size)
|
|
{
|
|
u_char *bp;
|
|
int cc;
|
|
int bytes_read;
|
|
|
|
bp = p->bp;
|
|
cc = p->cc;
|
|
|
|
/*
|
|
* Loop until we have the amount of data requested or we get
|
|
* an error or interrupt.
|
|
*/
|
|
while ((size_t)cc < size)
|
|
{
|
|
/*
|
|
* We haven't read all of the packet header yet.
|
|
* Read what remains, which could be all of it.
|
|
*/
|
|
bytes_read = sock_recv(rp->rmt_sockdata, rp->data_ssl, bp, size - cc,
|
|
SOCK_RECEIVEALL_NO|SOCK_EOF_IS_ERROR, p->errbuf,
|
|
PCAP_ERRBUF_SIZE);
|
|
|
|
if (bytes_read == -1)
|
|
{
|
|
/*
|
|
* Network error. Update the read pointer and
|
|
* byte count, and return an error indication.
|
|
*/
|
|
p->bp = bp;
|
|
p->cc = cc;
|
|
return -1;
|
|
}
|
|
if (bytes_read == -3)
|
|
{
|
|
/*
|
|
* Interrupted receive. Update the read
|
|
* pointer and byte count, and return
|
|
* an interrupted indication.
|
|
*/
|
|
p->bp = bp;
|
|
p->cc = cc;
|
|
return -3;
|
|
}
|
|
if (bytes_read == 0)
|
|
{
|
|
/*
|
|
* EOF - server terminated the connection.
|
|
* Update the read pointer and byte count, and
|
|
* return an error indication.
|
|
*/
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
|
|
"The server terminated the connection.");
|
|
return -1;
|
|
}
|
|
bp += bytes_read;
|
|
cc += bytes_read;
|
|
}
|
|
p->bp = bp;
|
|
p->cc = cc;
|
|
return 0;
|
|
}
|