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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright 2013 Red Hat, Inc.
* Author: Daniel Borkmann <dborkman@redhat.com>
* Chetan Loke <loke.chetan@gmail.com> (TPACKET_V3 usage example)
*
* A basic test of packet socket's TPACKET_V1/TPACKET_V2/TPACKET_V3 behavior.
*
* Control:
* Test the setup of the TPACKET socket with different patterns that are
* known to fail (TODO) resp. succeed (OK).
*
* Datapath:
* Open a pair of packet sockets and send resp. receive an a priori known
* packet pattern accross the sockets and check if it was received resp.
* sent correctly. Fanout in combination with RX_RING is currently not
* tested here.
*
* The test currently runs for
* - TPACKET_V1: RX_RING, TX_RING
* - TPACKET_V2: RX_RING, TX_RING
* - TPACKET_V3: RX_RING
*/
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <sys/mman.h>
#include <sys/utsname.h>
#include <linux/if_packet.h>
#include <linux/filter.h>
#include <ctype.h>
#include <fcntl.h>
#include <unistd.h>
#ifndef __ANDROID__
#include <bits/wordsize.h>
#endif
#include <net/ethernet.h>
#include <netinet/ip.h>
#include <arpa/inet.h>
#include <stdint.h>
#include <string.h>
#include <assert.h>
#include <net/if.h>
#include <inttypes.h>
#include <poll.h>
#include "psock_lib.h"
#include "../kselftest.h"
#ifndef bug_on
# define bug_on(cond) assert(!(cond))
#endif
#ifndef __aligned_tpacket
# define __aligned_tpacket __attribute__((aligned(TPACKET_ALIGNMENT)))
#endif
#ifndef __align_tpacket
# define __align_tpacket(x) __attribute__((aligned(TPACKET_ALIGN(x))))
#endif
#define NUM_PACKETS 100
#define ALIGN_8(x) (((x) + 8 - 1) & ~(8 - 1))
struct ring {
struct iovec *rd;
uint8_t *mm_space;
size_t mm_len, rd_len;
struct sockaddr_ll ll;
void (*walk)(int sock, struct ring *ring);
int type, rd_num, flen, version;
union {
struct tpacket_req req;
struct tpacket_req3 req3;
};
};
struct block_desc {
uint32_t version;
uint32_t offset_to_priv;
struct tpacket_hdr_v1 h1;
};
union frame_map {
struct {
struct tpacket_hdr tp_h __aligned_tpacket;
struct sockaddr_ll s_ll __align_tpacket(sizeof(struct tpacket_hdr));
} *v1;
struct {
struct tpacket2_hdr tp_h __aligned_tpacket;
struct sockaddr_ll s_ll __align_tpacket(sizeof(struct tpacket2_hdr));
} *v2;
void *raw;
};
static unsigned int total_packets, total_bytes;
static int pfsocket(int ver)
{
int ret, sock = socket(PF_PACKET, SOCK_RAW, 0);
if (sock == -1) {
perror("socket");
exit(1);
}
ret = setsockopt(sock, SOL_PACKET, PACKET_VERSION, &ver, sizeof(ver));
if (ret == -1) {
perror("setsockopt");
exit(1);
}
return sock;
}
static void status_bar_update(void)
{
if (total_packets % 10 == 0) {
fprintf(stderr, ".");
fflush(stderr);
}
}
static void test_payload(void *pay, size_t len)
{
struct ethhdr *eth = pay;
if (len < sizeof(struct ethhdr)) {
fprintf(stderr, "test_payload: packet too "
"small: %zu bytes!\n", len);
exit(1);
}
if (eth->h_proto != htons(ETH_P_IP)) {
fprintf(stderr, "test_payload: wrong ethernet "
"type: 0x%x!\n", ntohs(eth->h_proto));
exit(1);
}
}
static void create_payload(void *pay, size_t *len)
{
int i;
struct ethhdr *eth = pay;
struct iphdr *ip = pay + sizeof(*eth);
/* Lets create some broken crap, that still passes
* our BPF filter.
*/
*len = DATA_LEN + 42;
memset(pay, 0xff, ETH_ALEN * 2);
eth->h_proto = htons(ETH_P_IP);
for (i = 0; i < sizeof(*ip); ++i)
((uint8_t *) pay)[i + sizeof(*eth)] = (uint8_t) rand();
ip->ihl = 5;
ip->version = 4;
ip->protocol = 0x11;
ip->frag_off = 0;
ip->ttl = 64;
ip->tot_len = htons((uint16_t) *len - sizeof(*eth));
ip->saddr = htonl(INADDR_LOOPBACK);
ip->daddr = htonl(INADDR_LOOPBACK);
memset(pay + sizeof(*eth) + sizeof(*ip),
DATA_CHAR, DATA_LEN);
}
static inline int __v1_rx_kernel_ready(struct tpacket_hdr *hdr)
{
return ((hdr->tp_status & TP_STATUS_USER) == TP_STATUS_USER);
}
static inline void __v1_rx_user_ready(struct tpacket_hdr *hdr)
{
hdr->tp_status = TP_STATUS_KERNEL;
__sync_synchronize();
}
static inline int __v2_rx_kernel_ready(struct tpacket2_hdr *hdr)
{
return ((hdr->tp_status & TP_STATUS_USER) == TP_STATUS_USER);
}
static inline void __v2_rx_user_ready(struct tpacket2_hdr *hdr)
{
hdr->tp_status = TP_STATUS_KERNEL;
__sync_synchronize();
}
static inline int __v1_v2_rx_kernel_ready(void *base, int version)
{
switch (version) {
case TPACKET_V1:
return __v1_rx_kernel_ready(base);
case TPACKET_V2:
return __v2_rx_kernel_ready(base);
default:
bug_on(1);
return 0;
}
}
static inline void __v1_v2_rx_user_ready(void *base, int version)
{
switch (version) {
case TPACKET_V1:
__v1_rx_user_ready(base);
break;
case TPACKET_V2:
__v2_rx_user_ready(base);
break;
}
}
static void walk_v1_v2_rx(int sock, struct ring *ring)
{
struct pollfd pfd;
int udp_sock[2];
union frame_map ppd;
unsigned int frame_num = 0;
bug_on(ring->type != PACKET_RX_RING);
pair_udp_open(udp_sock, PORT_BASE);
memset(&pfd, 0, sizeof(pfd));
pfd.fd = sock;
pfd.events = POLLIN | POLLERR;
pfd.revents = 0;
pair_udp_send(udp_sock, NUM_PACKETS);
while (total_packets < NUM_PACKETS * 2) {
while (__v1_v2_rx_kernel_ready(ring->rd[frame_num].iov_base,
ring->version)) {
ppd.raw = ring->rd[frame_num].iov_base;
switch (ring->version) {
case TPACKET_V1:
test_payload((uint8_t *) ppd.raw + ppd.v1->tp_h.tp_mac,
ppd.v1->tp_h.tp_snaplen);
total_bytes += ppd.v1->tp_h.tp_snaplen;
break;
case TPACKET_V2:
test_payload((uint8_t *) ppd.raw + ppd.v2->tp_h.tp_mac,
ppd.v2->tp_h.tp_snaplen);
total_bytes += ppd.v2->tp_h.tp_snaplen;
break;
}
status_bar_update();
total_packets++;
__v1_v2_rx_user_ready(ppd.raw, ring->version);
frame_num = (frame_num + 1) % ring->rd_num;
}
poll(&pfd, 1, 1);
}
pair_udp_close(udp_sock);
if (total_packets != 2 * NUM_PACKETS) {
fprintf(stderr, "walk_v%d_rx: received %u out of %u pkts\n",
ring->version, total_packets, NUM_PACKETS);
exit(1);
}
fprintf(stderr, " %u pkts (%u bytes)", NUM_PACKETS, total_bytes >> 1);
}
static inline int __v1_tx_kernel_ready(struct tpacket_hdr *hdr)
{
return !(hdr->tp_status & (TP_STATUS_SEND_REQUEST | TP_STATUS_SENDING));
}
static inline void __v1_tx_user_ready(struct tpacket_hdr *hdr)
{
hdr->tp_status = TP_STATUS_SEND_REQUEST;
__sync_synchronize();
}
static inline int __v2_tx_kernel_ready(struct tpacket2_hdr *hdr)
{
return !(hdr->tp_status & (TP_STATUS_SEND_REQUEST | TP_STATUS_SENDING));
}
static inline void __v2_tx_user_ready(struct tpacket2_hdr *hdr)
{
hdr->tp_status = TP_STATUS_SEND_REQUEST;
__sync_synchronize();
}
static inline int __v3_tx_kernel_ready(struct tpacket3_hdr *hdr)
{
return !(hdr->tp_status & (TP_STATUS_SEND_REQUEST | TP_STATUS_SENDING));
}
static inline void __v3_tx_user_ready(struct tpacket3_hdr *hdr)
{
hdr->tp_status = TP_STATUS_SEND_REQUEST;
__sync_synchronize();
}
static inline int __tx_kernel_ready(void *base, int version)
{
switch (version) {
case TPACKET_V1:
return __v1_tx_kernel_ready(base);
case TPACKET_V2:
return __v2_tx_kernel_ready(base);
case TPACKET_V3:
return __v3_tx_kernel_ready(base);
default:
bug_on(1);
return 0;
}
}
static inline void __tx_user_ready(void *base, int version)
{
switch (version) {
case TPACKET_V1:
__v1_tx_user_ready(base);
break;
case TPACKET_V2:
__v2_tx_user_ready(base);
break;
case TPACKET_V3:
__v3_tx_user_ready(base);
break;
}
}
static void __v1_v2_set_packet_loss_discard(int sock)
{
int ret, discard = 1;
ret = setsockopt(sock, SOL_PACKET, PACKET_LOSS, (void *) &discard,
sizeof(discard));
if (ret == -1) {
perror("setsockopt");
exit(1);
}
}
static inline void *get_next_frame(struct ring *ring, int n)
{
uint8_t *f0 = ring->rd[0].iov_base;
switch (ring->version) {
case TPACKET_V1:
case TPACKET_V2:
return ring->rd[n].iov_base;
case TPACKET_V3:
return f0 + (n * ring->req3.tp_frame_size);
default:
bug_on(1);
return NULL;
}
}
static void walk_tx(int sock, struct ring *ring)
{
struct pollfd pfd;
int rcv_sock, ret;
size_t packet_len;
union frame_map ppd;
char packet[1024];
unsigned int frame_num = 0, got = 0;
struct sockaddr_ll ll = {
.sll_family = PF_PACKET,
.sll_halen = ETH_ALEN,
};
int nframes;
/* TPACKET_V{1,2} sets up the ring->rd* related variables based
* on frames (e.g., rd_num is tp_frame_nr) whereas V3 sets these
* up based on blocks (e.g, rd_num is tp_block_nr)
*/
if (ring->version <= TPACKET_V2)
nframes = ring->rd_num;
else
nframes = ring->req3.tp_frame_nr;
bug_on(ring->type != PACKET_TX_RING);
bug_on(nframes < NUM_PACKETS);
rcv_sock = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
if (rcv_sock == -1) {
perror("socket");
exit(1);
}
pair_udp_setfilter(rcv_sock);
ll.sll_ifindex = if_nametoindex("lo");
ret = bind(rcv_sock, (struct sockaddr *) &ll, sizeof(ll));
if (ret == -1) {
perror("bind");
exit(1);
}
memset(&pfd, 0, sizeof(pfd));
pfd.fd = sock;
pfd.events = POLLOUT | POLLERR;
pfd.revents = 0;
total_packets = NUM_PACKETS;
create_payload(packet, &packet_len);
while (total_packets > 0) {
void *next = get_next_frame(ring, frame_num);
while (__tx_kernel_ready(next, ring->version) &&
total_packets > 0) {
ppd.raw = next;
switch (ring->version) {
case TPACKET_V1:
ppd.v1->tp_h.tp_snaplen = packet_len;
ppd.v1->tp_h.tp_len = packet_len;
memcpy((uint8_t *) ppd.raw + TPACKET_HDRLEN -
sizeof(struct sockaddr_ll), packet,
packet_len);
total_bytes += ppd.v1->tp_h.tp_snaplen;
break;
case TPACKET_V2:
ppd.v2->tp_h.tp_snaplen = packet_len;
ppd.v2->tp_h.tp_len = packet_len;
memcpy((uint8_t *) ppd.raw + TPACKET2_HDRLEN -
sizeof(struct sockaddr_ll), packet,
packet_len);
total_bytes += ppd.v2->tp_h.tp_snaplen;
break;
case TPACKET_V3: {
struct tpacket3_hdr *tx = next;
tx->tp_snaplen = packet_len;
tx->tp_len = packet_len;
tx->tp_next_offset = 0;
memcpy((uint8_t *)tx + TPACKET3_HDRLEN -
sizeof(struct sockaddr_ll), packet,
packet_len);
total_bytes += tx->tp_snaplen;
break;
}
}
status_bar_update();
total_packets--;
__tx_user_ready(next, ring->version);
frame_num = (frame_num + 1) % nframes;
}
poll(&pfd, 1, 1);
}
bug_on(total_packets != 0);
ret = sendto(sock, NULL, 0, 0, NULL, 0);
if (ret == -1) {
perror("sendto");
exit(1);
}
while ((ret = recvfrom(rcv_sock, packet, sizeof(packet),
0, NULL, NULL)) > 0 &&
total_packets < NUM_PACKETS) {
got += ret;
test_payload(packet, ret);
status_bar_update();
total_packets++;
}
close(rcv_sock);
if (total_packets != NUM_PACKETS) {
fprintf(stderr, "walk_v%d_rx: received %u out of %u pkts\n",
ring->version, total_packets, NUM_PACKETS);
exit(1);
}
fprintf(stderr, " %u pkts (%u bytes)", NUM_PACKETS, got);
}
static void walk_v1_v2(int sock, struct ring *ring)
{
if (ring->type == PACKET_RX_RING)
walk_v1_v2_rx(sock, ring);
else
walk_tx(sock, ring);
}
static uint64_t __v3_prev_block_seq_num = 0;
void __v3_test_block_seq_num(struct block_desc *pbd)
{
if (__v3_prev_block_seq_num + 1 != pbd->h1.seq_num) {
fprintf(stderr, "\nprev_block_seq_num:%"PRIu64", expected "
"seq:%"PRIu64" != actual seq:%"PRIu64"\n",
__v3_prev_block_seq_num, __v3_prev_block_seq_num + 1,
(uint64_t) pbd->h1.seq_num);
exit(1);
}
__v3_prev_block_seq_num = pbd->h1.seq_num;
}
static void __v3_test_block_len(struct block_desc *pbd, uint32_t bytes, int block_num)
{
if (pbd->h1.num_pkts && bytes != pbd->h1.blk_len) {
fprintf(stderr, "\nblock:%u with %upackets, expected "
"len:%u != actual len:%u\n", block_num,
pbd->h1.num_pkts, bytes, pbd->h1.blk_len);
exit(1);
}
}
static void __v3_test_block_header(struct block_desc *pbd, const int block_num)
{
if ((pbd->h1.block_status & TP_STATUS_USER) == 0) {
fprintf(stderr, "\nblock %u: not in TP_STATUS_USER\n", block_num);
exit(1);
}
__v3_test_block_seq_num(pbd);
}
static void __v3_walk_block(struct block_desc *pbd, const int block_num)
{
int num_pkts = pbd->h1.num_pkts, i;
unsigned long bytes = 0, bytes_with_padding = ALIGN_8(sizeof(*pbd));
struct tpacket3_hdr *ppd;
__v3_test_block_header(pbd, block_num);
ppd = (struct tpacket3_hdr *) ((uint8_t *) pbd +
pbd->h1.offset_to_first_pkt);
for (i = 0; i < num_pkts; ++i) {
bytes += ppd->tp_snaplen;
if (ppd->tp_next_offset)
bytes_with_padding += ppd->tp_next_offset;
else
bytes_with_padding += ALIGN_8(ppd->tp_snaplen + ppd->tp_mac);
test_payload((uint8_t *) ppd + ppd->tp_mac, ppd->tp_snaplen);
status_bar_update();
total_packets++;
ppd = (struct tpacket3_hdr *) ((uint8_t *) ppd + ppd->tp_next_offset);
__sync_synchronize();
}
__v3_test_block_len(pbd, bytes_with_padding, block_num);
total_bytes += bytes;
}
void __v3_flush_block(struct block_desc *pbd)
{
pbd->h1.block_status = TP_STATUS_KERNEL;
__sync_synchronize();
}
static void walk_v3_rx(int sock, struct ring *ring)
{
unsigned int block_num = 0;
struct pollfd pfd;
struct block_desc *pbd;
int udp_sock[2];
bug_on(ring->type != PACKET_RX_RING);
pair_udp_open(udp_sock, PORT_BASE);
memset(&pfd, 0, sizeof(pfd));
pfd.fd = sock;
pfd.events = POLLIN | POLLERR;
pfd.revents = 0;
pair_udp_send(udp_sock, NUM_PACKETS);
while (total_packets < NUM_PACKETS * 2) {
pbd = (struct block_desc *) ring->rd[block_num].iov_base;
while ((pbd->h1.block_status & TP_STATUS_USER) == 0)
poll(&pfd, 1, 1);
__v3_walk_block(pbd, block_num);
__v3_flush_block(pbd);
block_num = (block_num + 1) % ring->rd_num;
}
pair_udp_close(udp_sock);
if (total_packets != 2 * NUM_PACKETS) {
fprintf(stderr, "walk_v3_rx: received %u out of %u pkts\n",
total_packets, NUM_PACKETS);
exit(1);
}
fprintf(stderr, " %u pkts (%u bytes)", NUM_PACKETS, total_bytes >> 1);
}
static void walk_v3(int sock, struct ring *ring)
{
if (ring->type == PACKET_RX_RING)
walk_v3_rx(sock, ring);
else
walk_tx(sock, ring);
}
static void __v1_v2_fill(struct ring *ring, unsigned int blocks)
{
ring->req.tp_block_size = getpagesize() << 2;
ring->req.tp_frame_size = TPACKET_ALIGNMENT << 7;
ring->req.tp_block_nr = blocks;
ring->req.tp_frame_nr = ring->req.tp_block_size /
ring->req.tp_frame_size *
ring->req.tp_block_nr;
ring->mm_len = ring->req.tp_block_size * ring->req.tp_block_nr;
ring->walk = walk_v1_v2;
ring->rd_num = ring->req.tp_frame_nr;
ring->flen = ring->req.tp_frame_size;
}
static void __v3_fill(struct ring *ring, unsigned int blocks, int type)
{
if (type == PACKET_RX_RING) {
ring->req3.tp_retire_blk_tov = 64;
ring->req3.tp_sizeof_priv = 0;
ring->req3.tp_feature_req_word = TP_FT_REQ_FILL_RXHASH;
}
ring->req3.tp_block_size = getpagesize() << 2;
ring->req3.tp_frame_size = TPACKET_ALIGNMENT << 7;
ring->req3.tp_block_nr = blocks;
ring->req3.tp_frame_nr = ring->req3.tp_block_size /
ring->req3.tp_frame_size *
ring->req3.tp_block_nr;
ring->mm_len = ring->req3.tp_block_size * ring->req3.tp_block_nr;
ring->walk = walk_v3;
ring->rd_num = ring->req3.tp_block_nr;
ring->flen = ring->req3.tp_block_size;
}
static void setup_ring(int sock, struct ring *ring, int version, int type)
{
int ret = 0;
unsigned int blocks = 256;
ring->type = type;
ring->version = version;
switch (version) {
case TPACKET_V1:
case TPACKET_V2:
if (type == PACKET_TX_RING)
__v1_v2_set_packet_loss_discard(sock);
__v1_v2_fill(ring, blocks);
ret = setsockopt(sock, SOL_PACKET, type, &ring->req,
sizeof(ring->req));
break;
case TPACKET_V3:
__v3_fill(ring, blocks, type);
ret = setsockopt(sock, SOL_PACKET, type, &ring->req3,
sizeof(ring->req3));
break;
}
if (ret == -1) {
perror("setsockopt");
exit(1);
}
ring->rd_len = ring->rd_num * sizeof(*ring->rd);
ring->rd = malloc(ring->rd_len);
if (ring->rd == NULL) {
perror("malloc");
exit(1);
}
total_packets = 0;
total_bytes = 0;
}
static void mmap_ring(int sock, struct ring *ring)
{
int i;
ring->mm_space = mmap(0, ring->mm_len, PROT_READ | PROT_WRITE,
MAP_SHARED | MAP_LOCKED | MAP_POPULATE, sock, 0);
if (ring->mm_space == MAP_FAILED) {
perror("mmap");
exit(1);
}
memset(ring->rd, 0, ring->rd_len);
for (i = 0; i < ring->rd_num; ++i) {
ring->rd[i].iov_base = ring->mm_space + (i * ring->flen);
ring->rd[i].iov_len = ring->flen;
}
}
static void bind_ring(int sock, struct ring *ring)
{
int ret;
pair_udp_setfilter(sock);
ring->ll.sll_family = PF_PACKET;
ring->ll.sll_protocol = htons(ETH_P_ALL);
ring->ll.sll_ifindex = if_nametoindex("lo");
ring->ll.sll_hatype = 0;
ring->ll.sll_pkttype = 0;
ring->ll.sll_halen = 0;
ret = bind(sock, (struct sockaddr *) &ring->ll, sizeof(ring->ll));
if (ret == -1) {
perror("bind");
exit(1);
}
}
static void walk_ring(int sock, struct ring *ring)
{
ring->walk(sock, ring);
}
static void unmap_ring(int sock, struct ring *ring)
{
munmap(ring->mm_space, ring->mm_len);
free(ring->rd);
}
static int test_kernel_bit_width(void)
{
char in[512], *ptr;
int num = 0, fd;
ssize_t ret;
fd = open("/proc/kallsyms", O_RDONLY);
if (fd == -1) {
perror("open");
exit(1);
}
ret = read(fd, in, sizeof(in));
if (ret <= 0) {
perror("read");
exit(1);
}
close(fd);
ptr = in;
while(!isspace(*ptr)) {
num++;
ptr++;
}
return num * 4;
}
static int test_user_bit_width(void)
{
return __WORDSIZE;
}
static const char *tpacket_str[] = {
[TPACKET_V1] = "TPACKET_V1",
[TPACKET_V2] = "TPACKET_V2",
[TPACKET_V3] = "TPACKET_V3",
};
static const char *type_str[] = {
[PACKET_RX_RING] = "PACKET_RX_RING",
[PACKET_TX_RING] = "PACKET_TX_RING",
};
static int test_tpacket(int version, int type)
{
int sock;
struct ring ring;
fprintf(stderr, "test: %s with %s ", tpacket_str[version],
type_str[type]);
fflush(stderr);
if (version == TPACKET_V1 &&
test_kernel_bit_width() != test_user_bit_width()) {
fprintf(stderr, "test: skip %s %s since user and kernel "
"space have different bit width\n",
tpacket_str[version], type_str[type]);
return KSFT_SKIP;
}
sock = pfsocket(version);
memset(&ring, 0, sizeof(ring));
setup_ring(sock, &ring, version, type);
mmap_ring(sock, &ring);
bind_ring(sock, &ring);
walk_ring(sock, &ring);
unmap_ring(sock, &ring);
close(sock);
fprintf(stderr, "\n");
return 0;
}
void get_kernel_version(int *version, int *patchlevel)
{
int ret, sublevel;
struct utsname utsname;
ret = uname(&utsname);
if (ret) {
perror("uname");
exit(1);
}
ret = sscanf(utsname.release, "%d.%d.%d", version, patchlevel,
&sublevel);
if (ret < 0) {
perror("sscanf");
exit(1);
} else if (ret != 3) {
printf("Malformed kernel version %s\n", &utsname.release);
exit(1);
}
}
int main(void)
{
int ret = 0;
int version, patchlevel;
get_kernel_version(&version, &patchlevel);
ret |= test_tpacket(TPACKET_V1, PACKET_RX_RING);
ret |= test_tpacket(TPACKET_V1, PACKET_TX_RING);
ret |= test_tpacket(TPACKET_V2, PACKET_RX_RING);
ret |= test_tpacket(TPACKET_V2, PACKET_TX_RING);
ret |= test_tpacket(TPACKET_V3, PACKET_RX_RING);
if (version > 4 || (version == 4 && patchlevel >= 11))
ret |= test_tpacket(TPACKET_V3, PACKET_TX_RING);
if (ret)
return 1;
printf("OK. All tests passed\n");
return 0;
}