// SPDX-License-Identifier: GPL-2.0
/* Test hardware checksum offload: Rx + Tx, IPv4 + IPv6, TCP + UDP.
*
* The test runs on two machines to exercise the NIC. For this reason it
* is not integrated in kselftests.
*
* CMD=$((./csum -[46] -[tu] -S $SADDR -D $DADDR -[RT] -r 1 $EXTRA_ARGS))
*
* Rx:
*
* The sender sends packets with a known checksum field using PF_INET(6)
* SOCK_RAW sockets.
*
* good packet: $CMD [-t]
* bad packet: $CMD [-t] -E
*
* The receiver reads UDP packets with a UDP socket. This is not an
* option for TCP packets ('-t'). Optionally insert an iptables filter
* to avoid these entering the real protocol stack.
*
* The receiver also reads all packets with a PF_PACKET socket, to
* observe whether both good and bad packets arrive on the host. And to
* read the optional TP_STATUS_CSUM_VALID bit. This requires setting
* option PACKET_AUXDATA, and works only for CHECKSUM_UNNECESSARY.
*
* Tx:
*
* The sender needs to build CHECKSUM_PARTIAL packets to exercise tx
* checksum offload.
*
* The sender can sends packets with a UDP socket.
*
* Optionally crafts a packet that sums up to zero to verify that the
* device writes negative zero 0xFFFF in this case to distinguish from
* 0x0000 (checksum disabled), as required by RFC 768. Hit this case
* by choosing a specific source port.
*
* good packet: $CMD -U
* zero csum: $CMD -U -Z
*
* The sender can also build packets with PF_PACKET with PACKET_VNET_HDR,
* to cover more protocols. PF_PACKET requires passing src and dst mac
* addresses.
*
* good packet: $CMD -s $smac -d $dmac -p [-t]
*
* Argument '-z' sends UDP packets with a 0x000 checksum disabled field,
* to verify that the NIC passes these packets unmodified.
*
* Argument '-e' adds a transport mode encapsulation header between
* network and transport header. This will fail for devices that parse
* headers. Should work on devices that implement protocol agnostic tx
* checksum offload (NETIF_F_HW_CSUM).
*
* Argument '-r $SEED' optionally randomizes header, payload and length
* to increase coverage between packets sent. SEED 1 further chooses a
* different seed for each run (and logs this for reproducibility). It
* is advised to enable this for extra coverage in continuous testing.
*/
#define _GNU_SOURCE
#include <arpa/inet.h>
#include <asm/byteorder.h>
#include <errno.h>
#include <error.h>
#include <linux/filter.h>
#include <linux/if_packet.h>
#include <linux/ipv6.h>
#include <linux/virtio_net.h>
#include <net/ethernet.h>
#include <net/if.h>
#include <netinet/if_ether.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/ip6.h>
#include <netinet/tcp.h>
#include <netinet/udp.h>
#include <poll.h>
#include <sched.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>
#include "kselftest.h"
static bool cfg_bad_csum;
static int cfg_family = PF_INET6;
static int cfg_num_pkt = 4;
static bool cfg_do_rx = true;
static bool cfg_do_tx = true;
static bool cfg_encap;
static char *cfg_ifname = "eth0";
static char *cfg_mac_dst;
static char *cfg_mac_src;
static int cfg_proto = IPPROTO_UDP;
static int cfg_payload_char = 'a';
static int cfg_payload_len = 100;
static uint16_t cfg_port_dst = 34000;
static uint16_t cfg_port_src = 33000;
static uint16_t cfg_port_src_encap = 33001;
static unsigned int cfg_random_seed;
static int cfg_rcvbuf = 1 << 22; /* be able to queue large cfg_num_pkt */
static bool cfg_send_pfpacket;
static bool cfg_send_udp;
static int cfg_timeout_ms = 2000;
static bool cfg_zero_disable; /* skip checksum: set to zero (udp only) */
static bool cfg_zero_sum; /* create packet that adds up to zero */
static struct sockaddr_in cfg_daddr4 = {.sin_family = AF_INET};
static struct sockaddr_in cfg_saddr4 = {.sin_family = AF_INET};
static struct sockaddr_in6 cfg_daddr6 = {.sin6_family = AF_INET6};
static struct sockaddr_in6 cfg_saddr6 = {.sin6_family = AF_INET6};
#define ENC_HEADER_LEN (sizeof(struct udphdr) + sizeof(struct udp_encap_hdr))
#define MAX_HEADER_LEN (sizeof(struct ipv6hdr) + ENC_HEADER_LEN + sizeof(struct tcphdr))
#define MAX_PAYLOAD_LEN 1024
/* Trivial demo encap. Stand-in for transport layer protocols like ESP or PSP */
struct udp_encap_hdr {
uint8_t nexthdr;
uint8_t padding[3];
};
/* Ipaddrs, for pseudo csum. Global var is ugly, pass through funcs was worse */
static void *iph_addr_p;
static unsigned long gettimeofday_ms(void)
{
struct timeval tv;
gettimeofday(&tv, NULL);
return (tv.tv_sec * 1000UL) + (tv.tv_usec / 1000UL);
}
static uint32_t checksum_nofold(char *data, size_t len, uint32_t sum)
{
uint16_t *words = (uint16_t *)data;
int i;
for (i = 0; i < len / 2; i++)
sum += words[i];
if (len & 1)
sum += ((unsigned char *)data)[len - 1];
return sum;
}
static uint16_t checksum_fold(void *data, size_t len, uint32_t sum)
{
sum = checksum_nofold(data, len, sum);
while (sum > 0xFFFF)
sum = (sum & 0xFFFF) + (sum >> 16);
return ~sum;
}
static uint16_t checksum(void *th, uint16_t proto, size_t len)
{
uint32_t sum;
int alen;
alen = cfg_family == PF_INET6 ? 32 : 8;
sum = checksum_nofold(iph_addr_p, alen, 0);
sum += htons(proto);
sum += htons(len);
/* With CHECKSUM_PARTIAL kernel expects non-inverted pseudo csum */
if (cfg_do_tx && cfg_send_pfpacket)
return ~checksum_fold(NULL, 0, sum);
else
return checksum_fold(th, len, sum);
}
static void *build_packet_ipv4(void *_iph, uint8_t proto, unsigned int len)
{
struct iphdr *iph = _iph;
memset(iph, 0, sizeof(*iph));
iph->version = 4;
iph->ihl = 5;
iph->ttl = 8;
iph->protocol = proto;
iph->saddr = cfg_saddr4.sin_addr.s_addr;
iph->daddr = cfg_daddr4.sin_addr.s_addr;
iph->tot_len = htons(sizeof(*iph) + len);
iph->check = checksum_fold(iph, sizeof(*iph), 0);
iph_addr_p = &iph->saddr;
return iph + 1;
}
static void *build_packet_ipv6(void *_ip6h, uint8_t proto, unsigned int len)
{
struct ipv6hdr *ip6h = _ip6h;
memset(ip6h, 0, sizeof(*ip6h));
ip6h->version = 6;
ip6h->payload_len = htons(len);
ip6h->nexthdr = proto;
ip6h->hop_limit = 64;
ip6h->saddr = cfg_saddr6.sin6_addr;
ip6h->daddr = cfg_daddr6.sin6_addr;
iph_addr_p = &ip6h->saddr;
return ip6h + 1;
}
static void *build_packet_udp(void *_uh)
{
struct udphdr *uh = _uh;
uh->source = htons(cfg_port_src);
uh->dest = htons(cfg_port_dst);
uh->len = htons(sizeof(*uh) + cfg_payload_len);
uh->check = 0;
/* choose source port so that uh->check adds up to zero */
if (cfg_zero_sum) {
uh->source = 0;
uh->source = checksum(uh, IPPROTO_UDP, sizeof(*uh) + cfg_payload_len);
fprintf(stderr, "tx: changing sport: %hu -> %hu\n",
cfg_port_src, ntohs(uh->source));
cfg_port_src = ntohs(uh->source);
}
if (cfg_zero_disable)
uh->check = 0;
else
uh->check = checksum(uh, IPPROTO_UDP, sizeof(*uh) + cfg_payload_len);
if (cfg_bad_csum)
uh->check = ~uh->check;
fprintf(stderr, "tx: sending checksum: 0x%x\n", uh->check);
return uh + 1;
}
static void *build_packet_tcp(void *_th)
{
struct tcphdr *th = _th;
th->source = htons(cfg_port_src);
th->dest = htons(cfg_port_dst);
th->doff = 5;
th->check = 0;
th->check = checksum(th, IPPROTO_TCP, sizeof(*th) + cfg_payload_len);
if (cfg_bad_csum)
th->check = ~th->check;
fprintf(stderr, "tx: sending checksum: 0x%x\n", th->check);
return th + 1;
}
static char *build_packet_udp_encap(void *_uh)
{
struct udphdr *uh = _uh;
struct udp_encap_hdr *eh = _uh + sizeof(*uh);
/* outer dst == inner dst, to simplify BPF filter
* outer src != inner src, to demultiplex on recv
*/
uh->dest = htons(cfg_port_dst);
uh->source = htons(cfg_port_src_encap);
uh->check = 0;
uh->len = htons(sizeof(*uh) +
sizeof(*eh) +
sizeof(struct tcphdr) +
cfg_payload_len);
eh->nexthdr = IPPROTO_TCP;
return build_packet_tcp(eh + 1);
}
static char *build_packet(char *buf, int max_len, int *len)
{
uint8_t proto;
char *off;
int tlen;
if (cfg_random_seed) {
int *buf32 = (void *)buf;
int i;
for (i = 0; i < (max_len / sizeof(int)); i++)
buf32[i] = rand();
} else {
memset(buf, cfg_payload_char, max_len);
}
if (cfg_proto == IPPROTO_UDP)
tlen = sizeof(struct udphdr) + cfg_payload_len;
else
tlen = sizeof(struct tcphdr) + cfg_payload_len;
if (cfg_encap) {
proto = IPPROTO_UDP;
tlen += ENC_HEADER_LEN;
} else {
proto = cfg_proto;
}
if (cfg_family == PF_INET)
off = build_packet_ipv4(buf, proto, tlen);
else
off = build_packet_ipv6(buf, proto, tlen);
if (cfg_encap)
off = build_packet_udp_encap(off);
else if (cfg_proto == IPPROTO_UDP)
off = build_packet_udp(off);
else
off = build_packet_tcp(off);
/* only pass the payload, but still compute headers for cfg_zero_sum */
if (cfg_send_udp) {
*len = cfg_payload_len;
return off;
}
*len = off - buf + cfg_payload_len;
return buf;
}
static int open_inet(int ipproto, int protocol)
{
int fd;
fd = socket(cfg_family, ipproto, protocol);
if (fd == -1)
error(1, errno, "socket inet");
if (cfg_family == PF_INET6) {
/* may have been updated by cfg_zero_sum */
cfg_saddr6.sin6_port = htons(cfg_port_src);
if (bind(fd, (void *)&cfg_saddr6, sizeof(cfg_saddr6)))
error(1, errno, "bind dgram 6");
if (connect(fd, (void *)&cfg_daddr6, sizeof(cfg_daddr6)))
error(1, errno, "connect dgram 6");
} else {
/* may have been updated by cfg_zero_sum */
cfg_saddr4.sin_port = htons(cfg_port_src);
if (bind(fd, (void *)&cfg_saddr4, sizeof(cfg_saddr4)))
error(1, errno, "bind dgram 4");
if (connect(fd, (void *)&cfg_daddr4, sizeof(cfg_daddr4)))
error(1, errno, "connect dgram 4");
}
return fd;
}
static int open_packet(void)
{
int fd, one = 1;
fd = socket(PF_PACKET, SOCK_RAW, 0);
if (fd == -1)
error(1, errno, "socket packet");
if (setsockopt(fd, SOL_PACKET, PACKET_VNET_HDR, &one, sizeof(one)))
error(1, errno, "setsockopt packet_vnet_ndr");
return fd;
}
static void send_inet(int fd, const char *buf, int len)
{
int ret;
ret = write(fd, buf, len);
if (ret == -1)
error(1, errno, "write");
if (ret != len)
error(1, 0, "write: %d", ret);
}
static void eth_str_to_addr(const char *str, unsigned char *eth)
{
if (sscanf(str, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx",
ð[0], ð[1], ð[2], ð[3], ð[4], ð[5]) != 6)
error(1, 0, "cannot parse mac addr %s", str);
}
static void send_packet(int fd, const char *buf, int len)
{
struct virtio_net_hdr vh = {0};
struct sockaddr_ll addr = {0};
struct msghdr msg = {0};
struct ethhdr eth;
struct iovec iov[3];
int ret;
addr.sll_family = AF_PACKET;
addr.sll_halen = ETH_ALEN;
addr.sll_ifindex = if_nametoindex(cfg_ifname);
if (!addr.sll_ifindex)
error(1, errno, "if_nametoindex %s", cfg_ifname);
vh.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
if (cfg_family == PF_INET6) {
vh.csum_start = sizeof(struct ethhdr) + sizeof(struct ipv6hdr);
addr.sll_protocol = htons(ETH_P_IPV6);
} else {
vh.csum_start = sizeof(struct ethhdr) + sizeof(struct iphdr);
addr.sll_protocol = htons(ETH_P_IP);
}
if (cfg_encap)
vh.csum_start += ENC_HEADER_LEN;
if (cfg_proto == IPPROTO_TCP) {
vh.csum_offset = __builtin_offsetof(struct tcphdr, check);
vh.hdr_len = vh.csum_start + sizeof(struct tcphdr);
} else {
vh.csum_offset = __builtin_offsetof(struct udphdr, check);
vh.hdr_len = vh.csum_start + sizeof(struct udphdr);
}
eth_str_to_addr(cfg_mac_src, eth.h_source);
eth_str_to_addr(cfg_mac_dst, eth.h_dest);
eth.h_proto = addr.sll_protocol;
iov[0].iov_base = &vh;
iov[0].iov_len = sizeof(vh);
iov[1].iov_base = ð
iov[1].iov_len = sizeof(eth);
iov[2].iov_base = (void *)buf;
iov[2].iov_len = len;
msg.msg_iov = iov;
msg.msg_iovlen = ARRAY_SIZE(iov);
msg.msg_name = &addr;
msg.msg_namelen = sizeof(addr);
ret = sendmsg(fd, &msg, 0);
if (ret == -1)
error(1, errno, "sendmsg packet");
if (ret != sizeof(vh) + sizeof(eth) + len)
error(1, errno, "sendmsg packet: %u", ret);
}
static int recv_prepare_udp(void)
{
int fd;
fd = socket(cfg_family, SOCK_DGRAM, 0);
if (fd == -1)
error(1, errno, "socket r");
if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF,
&cfg_rcvbuf, sizeof(cfg_rcvbuf)))
error(1, errno, "setsockopt SO_RCVBUF r");
if (cfg_family == PF_INET6) {
if (bind(fd, (void *)&cfg_daddr6, sizeof(cfg_daddr6)))
error(1, errno, "bind r");
} else {
if (bind(fd, (void *)&cfg_daddr4, sizeof(cfg_daddr4)))
error(1, errno, "bind r");
}
return fd;
}
/* Filter out all traffic that is not cfg_proto with our destination port.
*
* Otherwise background noise may cause PF_PACKET receive queue overflow,
* dropping the expected packets and failing the test.
*/
static void __recv_prepare_packet_filter(int fd, int off_nexthdr, int off_dport)
{
struct sock_filter filter[] = {
BPF_STMT(BPF_LD + BPF_B + BPF_ABS, SKF_AD_OFF + SKF_AD_PKTTYPE),
BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, PACKET_HOST, 0, 4),
BPF_STMT(BPF_LD + BPF_B + BPF_ABS, off_nexthdr),
BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, cfg_encap ? IPPROTO_UDP : cfg_proto, 0, 2),
BPF_STMT(BPF_LD + BPF_H + BPF_ABS, off_dport),
BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, cfg_port_dst, 1, 0),
BPF_STMT(BPF_RET + BPF_K, 0),
BPF_STMT(BPF_RET + BPF_K, 0xFFFF),
};
struct sock_fprog prog = {};
prog.filter = filter;
prog.len = ARRAY_SIZE(filter);
if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &prog, sizeof(prog)))
error(1, errno, "setsockopt filter");
}
static void recv_prepare_packet_filter(int fd)
{
const int off_dport = offsetof(struct tcphdr, dest); /* same for udp */
if (cfg_family == AF_INET)
__recv_prepare_packet_filter(fd, offsetof(struct iphdr, protocol),
sizeof(struct iphdr) + off_dport);
else
__recv_prepare_packet_filter(fd, offsetof(struct ipv6hdr, nexthdr),
sizeof(struct ipv6hdr) + off_dport);
}
static void recv_prepare_packet_bind(int fd)
{
struct sockaddr_ll laddr = {0};
laddr.sll_family = AF_PACKET;
if (cfg_family == PF_INET)
laddr.sll_protocol = htons(ETH_P_IP);
else
laddr.sll_protocol = htons(ETH_P_IPV6);
laddr.sll_ifindex = if_nametoindex(cfg_ifname);
if (!laddr.sll_ifindex)
error(1, 0, "if_nametoindex %s", cfg_ifname);
if (bind(fd, (void *)&laddr, sizeof(laddr)))
error(1, errno, "bind pf_packet");
}
static int recv_prepare_packet(void)
{
int fd, one = 1;
fd = socket(PF_PACKET, SOCK_DGRAM, 0);
if (fd == -1)
error(1, errno, "socket p");
if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF,
&cfg_rcvbuf, sizeof(cfg_rcvbuf)))
error(1, errno, "setsockopt SO_RCVBUF p");
/* enable auxdata to recv checksum status (valid vs unknown) */
if (setsockopt(fd, SOL_PACKET, PACKET_AUXDATA, &one, sizeof(one)))
error(1, errno, "setsockopt auxdata");
/* install filter to restrict packet flow to match */
recv_prepare_packet_filter(fd);
/* bind to address family to start packet flow */
recv_prepare_packet_bind(fd);
return fd;
}
static int recv_udp(int fd)
{
static char buf[MAX_PAYLOAD_LEN];
int ret, count = 0;
while (1) {
ret = recv(fd, buf, sizeof(buf), MSG_DONTWAIT);
if (ret == -1 && errno == EAGAIN)
break;
if (ret == -1)
error(1, errno, "recv r");
fprintf(stderr, "rx: udp: len=%u\n", ret);
count++;
}
return count;
}
static int recv_verify_csum(void *th, int len, uint16_t sport, uint16_t csum_field)
{
uint16_t csum;
csum = checksum(th, cfg_proto, len);
fprintf(stderr, "rx: pkt: sport=%hu len=%u csum=0x%hx verify=0x%hx\n",
sport, len, csum_field, csum);
/* csum must be zero unless cfg_bad_csum indicates bad csum */
if (csum && !cfg_bad_csum) {
fprintf(stderr, "pkt: bad csum\n");
return 1;
} else if (cfg_bad_csum && !csum) {
fprintf(stderr, "pkt: good csum, while bad expected\n");
return 1;
}
if (cfg_zero_sum && csum_field != 0xFFFF) {
fprintf(stderr, "pkt: zero csum: field should be 0xFFFF, is 0x%hx\n", csum_field);
return 1;
}
return 0;
}
static int recv_verify_packet_tcp(void *th, int len)
{
struct tcphdr *tcph = th;
if (len < sizeof(*tcph) || tcph->dest != htons(cfg_port_dst))
return -1;
return recv_verify_csum(th, len, ntohs(tcph->source), tcph->check);
}
static int recv_verify_packet_udp_encap(void *th, int len)
{
struct udp_encap_hdr *eh = th;
if (len < sizeof(*eh) || eh->nexthdr != IPPROTO_TCP)
return -1;
return recv_verify_packet_tcp(eh + 1, len - sizeof(*eh));
}
static int recv_verify_packet_udp(void *th, int len)
{
struct udphdr *udph = th;
if (len < sizeof(*udph))
return -1;
if (udph->dest != htons(cfg_port_dst))
return -1;
if (udph->source == htons(cfg_port_src_encap))
return recv_verify_packet_udp_encap(udph + 1,
len - sizeof(*udph));
return recv_verify_csum(th, len, ntohs(udph->source), udph->check);
}
static int recv_verify_packet_ipv4(void *nh, int len)
{
struct iphdr *iph = nh;
uint16_t proto = cfg_encap ? IPPROTO_UDP : cfg_proto;
uint16_t ip_len;
if (len < sizeof(*iph) || iph->protocol != proto)
return -1;
ip_len = ntohs(iph->tot_len);
if (ip_len > len || ip_len < sizeof(*iph))
return -1;
len = ip_len;
iph_addr_p = &iph->saddr;
if (proto == IPPROTO_TCP)
return recv_verify_packet_tcp(iph + 1, len - sizeof(*iph));
else
return recv_verify_packet_udp(iph + 1, len - sizeof(*iph));
}
static int recv_verify_packet_ipv6(void *nh, int len)
{
struct ipv6hdr *ip6h = nh;
uint16_t proto = cfg_encap ? IPPROTO_UDP : cfg_proto;
uint16_t ip_len;
if (len < sizeof(*ip6h) || ip6h->nexthdr != proto)
return -1;
ip_len = ntohs(ip6h->payload_len);
if (ip_len > len - sizeof(*ip6h))
return -1;
len = ip_len;
iph_addr_p = &ip6h->saddr;
if (proto == IPPROTO_TCP)
return recv_verify_packet_tcp(ip6h + 1, len);
else
return recv_verify_packet_udp(ip6h + 1, len);
}
/* return whether auxdata includes TP_STATUS_CSUM_VALID */
static uint32_t recv_get_packet_csum_status(struct msghdr *msg)
{
struct tpacket_auxdata *aux = NULL;
struct cmsghdr *cm;
if (msg->msg_flags & MSG_CTRUNC)
error(1, 0, "cmsg: truncated");
for (cm = CMSG_FIRSTHDR(msg); cm; cm = CMSG_NXTHDR(msg, cm)) {
if (cm->cmsg_level != SOL_PACKET ||
cm->cmsg_type != PACKET_AUXDATA)
error(1, 0, "cmsg: level=%d type=%d\n",
cm->cmsg_level, cm->cmsg_type);
if (cm->cmsg_len != CMSG_LEN(sizeof(struct tpacket_auxdata)))
error(1, 0, "cmsg: len=%lu expected=%lu",
cm->cmsg_len, CMSG_LEN(sizeof(struct tpacket_auxdata)));
aux = (void *)CMSG_DATA(cm);
}
if (!aux)
error(1, 0, "cmsg: no auxdata");
return aux->tp_status;
}
static int recv_packet(int fd)
{
static char _buf[MAX_HEADER_LEN + MAX_PAYLOAD_LEN];
unsigned long total = 0, bad_csums = 0, bad_validations = 0;
char ctrl[CMSG_SPACE(sizeof(struct tpacket_auxdata))];
struct pkt *buf = (void *)_buf;
struct msghdr msg = {0};
uint32_t tp_status;
struct iovec iov;
int len, ret;
iov.iov_base = _buf;
iov.iov_len = sizeof(_buf);
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
msg.msg_control = ctrl;
msg.msg_controllen = sizeof(ctrl);
while (1) {
msg.msg_flags = 0;
len = recvmsg(fd, &msg, MSG_DONTWAIT);
if (len == -1 && errno == EAGAIN)
break;
if (len == -1)
error(1, errno, "recv p");
tp_status = recv_get_packet_csum_status(&msg);
/* GRO might coalesce randomized packets. Such GSO packets are
* then reinitialized for csum offload (CHECKSUM_PARTIAL), with
* a pseudo csum. Do not try to validate these checksums.
*/
if (tp_status & TP_STATUS_CSUMNOTREADY) {
fprintf(stderr, "cmsg: GSO packet has partial csum: skip\n");
continue;
}
if (cfg_family == PF_INET6)
ret = recv_verify_packet_ipv6(buf, len);
else
ret = recv_verify_packet_ipv4(buf, len);
if (ret == -1 /* skip: non-matching */)
continue;
total++;
if (ret == 1)
bad_csums++;
/* Fail if kernel returns valid for known bad csum.
* Do not fail if kernel does not validate a good csum:
* Absence of validation does not imply invalid.
*/
if (tp_status & TP_STATUS_CSUM_VALID && cfg_bad_csum) {
fprintf(stderr, "cmsg: expected bad csum, pf_packet returns valid\n");
bad_validations++;
}
}
if (bad_csums || bad_validations)
error(1, 0, "rx: errors at pf_packet: total=%lu bad_csums=%lu bad_valids=%lu\n",
total, bad_csums, bad_validations);
return total;
}
static void parse_args(int argc, char *const argv[])
{
const char *daddr = NULL, *saddr = NULL;
int c;
while ((c = getopt(argc, argv, "46d:D:eEi:l:L:n:r:PRs:S:tTuUzZ")) != -1) {
switch (c) {
case '4':
cfg_family = PF_INET;
break;
case '6':
cfg_family = PF_INET6;
break;
case 'd':
cfg_mac_dst = optarg;
break;
case 'D':
daddr = optarg;
break;
case 'e':
cfg_encap = true;
break;
case 'E':
cfg_bad_csum = true;
break;
case 'i':
cfg_ifname = optarg;
break;
case 'l':
cfg_payload_len = strtol(optarg, NULL, 0);
break;
case 'L':
cfg_timeout_ms = strtol(optarg, NULL, 0) * 1000;
break;
case 'n':
cfg_num_pkt = strtol(optarg, NULL, 0);
break;
case 'r':
cfg_random_seed = strtol(optarg, NULL, 0);
break;
case 'P':
cfg_send_pfpacket = true;
break;
case 'R':
/* only Rx: used with two machine tests */
cfg_do_tx = false;
break;
case 's':
cfg_mac_src = optarg;
break;
case 'S':
saddr = optarg;
break;
case 't':
cfg_proto = IPPROTO_TCP;
break;
case 'T':
/* only Tx: used with two machine tests */
cfg_do_rx = false;
break;
case 'u':
cfg_proto = IPPROTO_UDP;
break;
case 'U':
/* send using real udp socket,
* to exercise tx checksum offload
*/
cfg_send_udp = true;
break;
case 'z':
cfg_zero_disable = true;
break;
case 'Z':
cfg_zero_sum = true;
break;
default:
error(1, 0, "unknown arg %c", c);
}
}
if (!daddr || !saddr)
error(1, 0, "Must pass -D <daddr> and -S <saddr>");
if (cfg_do_tx && cfg_send_pfpacket && (!cfg_mac_src || !cfg_mac_dst))
error(1, 0, "Transmit with pf_packet requires mac addresses");
if (cfg_payload_len > MAX_PAYLOAD_LEN)
error(1, 0, "Payload length exceeds max");
if (cfg_proto != IPPROTO_UDP && (cfg_zero_sum || cfg_zero_disable))
error(1, 0, "Only UDP supports zero csum");
if (cfg_zero_sum && !cfg_send_udp)
error(1, 0, "Zero checksum conversion requires -U for tx csum offload");
if (cfg_zero_sum && cfg_bad_csum)
error(1, 0, "Cannot combine zero checksum conversion and invalid checksum");
if (cfg_zero_sum && cfg_random_seed)
error(1, 0, "Cannot combine zero checksum conversion with randomization");
if (cfg_family == PF_INET6) {
cfg_saddr6.sin6_port = htons(cfg_port_src);
cfg_daddr6.sin6_port = htons(cfg_port_dst);
if (inet_pton(cfg_family, daddr, &cfg_daddr6.sin6_addr) != 1)
error(1, errno, "Cannot parse ipv6 -D");
if (inet_pton(cfg_family, saddr, &cfg_saddr6.sin6_addr) != 1)
error(1, errno, "Cannot parse ipv6 -S");
} else {
cfg_saddr4.sin_port = htons(cfg_port_src);
cfg_daddr4.sin_port = htons(cfg_port_dst);
if (inet_pton(cfg_family, daddr, &cfg_daddr4.sin_addr) != 1)
error(1, errno, "Cannot parse ipv4 -D");
if (inet_pton(cfg_family, saddr, &cfg_saddr4.sin_addr) != 1)
error(1, errno, "Cannot parse ipv4 -S");
}
if (cfg_do_tx && cfg_random_seed) {
/* special case: time-based seed */
if (cfg_random_seed == 1)
cfg_random_seed = (unsigned int)gettimeofday_ms();
srand(cfg_random_seed);
fprintf(stderr, "randomization seed: %u\n", cfg_random_seed);
}
}
static void do_tx(void)
{
static char _buf[MAX_HEADER_LEN + MAX_PAYLOAD_LEN];
char *buf;
int fd, len, i;
buf = build_packet(_buf, sizeof(_buf), &len);
if (cfg_send_pfpacket)
fd = open_packet();
else if (cfg_send_udp)
fd = open_inet(SOCK_DGRAM, 0);
else
fd = open_inet(SOCK_RAW, IPPROTO_RAW);
for (i = 0; i < cfg_num_pkt; i++) {
if (cfg_send_pfpacket)
send_packet(fd, buf, len);
else
send_inet(fd, buf, len);
/* randomize each packet individually to increase coverage */
if (cfg_random_seed) {
cfg_payload_len = rand() % MAX_PAYLOAD_LEN;
buf = build_packet(_buf, sizeof(_buf), &len);
}
}
if (close(fd))
error(1, errno, "close tx");
}
static void do_rx(int fdp, int fdr)
{
unsigned long count_udp = 0, count_pkt = 0;
long tleft, tstop;
struct pollfd pfd;
tstop = gettimeofday_ms() + cfg_timeout_ms;
tleft = cfg_timeout_ms;
do {
pfd.events = POLLIN;
pfd.fd = fdp;
if (poll(&pfd, 1, tleft) == -1)
error(1, errno, "poll");
if (pfd.revents & POLLIN)
count_pkt += recv_packet(fdp);
if (cfg_proto == IPPROTO_UDP)
count_udp += recv_udp(fdr);
tleft = tstop - gettimeofday_ms();
} while (tleft > 0);
if (close(fdr))
error(1, errno, "close r");
if (close(fdp))
error(1, errno, "close p");
if (count_pkt < cfg_num_pkt)
error(1, 0, "rx: missing packets at pf_packet: %lu < %u",
count_pkt, cfg_num_pkt);
if (cfg_proto == IPPROTO_UDP) {
if (cfg_bad_csum && count_udp)
error(1, 0, "rx: unexpected packets at udp");
if (!cfg_bad_csum && !count_udp)
error(1, 0, "rx: missing packets at udp");
}
}
int main(int argc, char *const argv[])
{
int fdp = -1, fdr = -1; /* -1 to silence -Wmaybe-uninitialized */
parse_args(argc, argv);
/* open receive sockets before transmitting */
if (cfg_do_rx) {
fdp = recv_prepare_packet();
fdr = recv_prepare_udp();
}
if (cfg_do_tx)
do_tx();
if (cfg_do_rx)
do_rx(fdp, fdr);
fprintf(stderr, "OK\n");
return 0;
}
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