// SPDX-License-Identifier: GPL-2.0 /* * This testsuite provides conformance testing for GRO coalescing. * * Test cases: * 1.data * Data packets of the same size and same header setup with correct * sequence numbers coalesce. The one exception being the last data * packet coalesced: it can be smaller than the rest and coalesced * as long as it is in the same flow. * 2.ack * Pure ACK does not coalesce. * 3.flags * Specific test cases: no packets with PSH, SYN, URG, RST set will * be coalesced. * 4.tcp * Packets with incorrect checksum, non-consecutive seqno and * different TCP header options shouldn't coalesce. Nit: given that * some extension headers have paddings, such as timestamp, headers * that are padding differently would not be coalesced. * 5.ip: * Packets with different (ECN, TTL, TOS) header, ip options or * ip fragments (ipv6) shouldn't coalesce. * 6.large: * Packets larger than GRO_MAX_SIZE packets shouldn't coalesce. * * MSS is defined as 4096 - header because if it is too small * (i.e. 1500 MTU - header), it will result in many packets, * increasing the "large" test case's flakiness. This is because * due to time sensitivity in the coalescing window, the receiver * may not coalesce all of the packets. * * Note the timing issue applies to all of the test cases, so some * flakiness is to be expected. * */ #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "../kselftest.h" #define DPORT 8000 #define SPORT 1500 #define PAYLOAD_LEN 100 #define NUM_PACKETS 4 #define START_SEQ 100 #define START_ACK 100 #define ETH_P_NONE 0 #define TOTAL_HDR_LEN (ETH_HLEN + sizeof(struct ipv6hdr) + sizeof(struct tcphdr)) #define MSS (4096 - sizeof(struct tcphdr) - sizeof(struct ipv6hdr)) #define MAX_PAYLOAD (IP_MAXPACKET - sizeof(struct tcphdr) - sizeof(struct ipv6hdr)) #define NUM_LARGE_PKT (MAX_PAYLOAD / MSS) #define MAX_HDR_LEN (ETH_HLEN + sizeof(struct ipv6hdr) + sizeof(struct tcphdr)) #define MIN_EXTHDR_SIZE 8 #define EXT_PAYLOAD_1 "\x00\x00\x00\x00\x00\x00" #define EXT_PAYLOAD_2 "\x11\x11\x11\x11\x11\x11" #define ipv6_optlen(p) (((p)->hdrlen+1) << 3) /* calculate IPv6 extension header len */ #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)])) static const char *addr6_src = "fdaa::2"; static const char *addr6_dst = "fdaa::1"; static const char *addr4_src = "192.168.1.200"; static const char *addr4_dst = "192.168.1.100"; static int proto = -1; static uint8_t src_mac[ETH_ALEN], dst_mac[ETH_ALEN]; static char *testname = "data"; static char *ifname = "eth0"; static char *smac = "aa:00:00:00:00:02"; static char *dmac = "aa:00:00:00:00:01"; static bool verbose; static bool tx_socket = true; static int tcp_offset = -1; static int total_hdr_len = -1; static int ethhdr_proto = -1; static const int num_flush_id_cases = 6; static void vlog(const char *fmt, ...) { va_list args; if (verbose) { va_start(args, fmt); vfprintf(stderr, fmt, args); va_end(args); } } static void setup_sock_filter(int fd) { const int dport_off = tcp_offset + offsetof(struct tcphdr, dest); const int ethproto_off = offsetof(struct ethhdr, h_proto); int optlen = 0; int ipproto_off, opt_ipproto_off; int next_off; if (proto == PF_INET) next_off = offsetof(struct iphdr, protocol); else next_off = offsetof(struct ipv6hdr, nexthdr); ipproto_off = ETH_HLEN + next_off; /* Overridden later if exthdrs are used: */ opt_ipproto_off = ipproto_off; if (strcmp(testname, "ip") == 0) { if (proto == PF_INET) optlen = sizeof(struct ip_timestamp); else { BUILD_BUG_ON(sizeof(struct ip6_hbh) > MIN_EXTHDR_SIZE); BUILD_BUG_ON(sizeof(struct ip6_dest) > MIN_EXTHDR_SIZE); BUILD_BUG_ON(sizeof(struct ip6_frag) > MIN_EXTHDR_SIZE); /* same size for HBH and Fragment extension header types */ optlen = MIN_EXTHDR_SIZE; opt_ipproto_off = ETH_HLEN + sizeof(struct ipv6hdr) + offsetof(struct ip6_ext, ip6e_nxt); } } /* this filter validates the following: * - packet is IPv4/IPv6 according to the running test. * - packet is TCP. Also handles the case of one extension header and then TCP. * - checks the packet tcp dport equals to DPORT. Also handles the case of one * extension header and then TCP. */ struct sock_filter filter[] = { BPF_STMT(BPF_LD + BPF_H + BPF_ABS, ethproto_off), BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ntohs(ethhdr_proto), 0, 9), BPF_STMT(BPF_LD + BPF_B + BPF_ABS, ipproto_off), BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, IPPROTO_TCP, 2, 0), BPF_STMT(BPF_LD + BPF_B + BPF_ABS, opt_ipproto_off), BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, IPPROTO_TCP, 0, 5), BPF_STMT(BPF_LD + BPF_H + BPF_ABS, dport_off), BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, DPORT, 2, 0), BPF_STMT(BPF_LD + BPF_H + BPF_ABS, dport_off + optlen), BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, DPORT, 0, 1), BPF_STMT(BPF_RET + BPF_K, 0xFFFFFFFF), BPF_STMT(BPF_RET + BPF_K, 0), }; struct sock_fprog bpf = { .len = ARRAY_SIZE(filter), .filter = filter, }; if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &bpf, sizeof(bpf)) < 0) error(1, errno, "error setting filter"); } static uint32_t checksum_nofold(void *data, size_t len, uint32_t sum) { uint16_t *words = data; int i; for (i = 0; i < len / 2; i++) sum += words[i]; if (len & 1) sum += ((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 tcp_checksum(void *buf, int payload_len) { struct pseudo_header6 { struct in6_addr saddr; struct in6_addr daddr; uint16_t protocol; uint16_t payload_len; } ph6; struct pseudo_header4 { struct in_addr saddr; struct in_addr daddr; uint16_t protocol; uint16_t payload_len; } ph4; uint32_t sum = 0; if (proto == PF_INET6) { if (inet_pton(AF_INET6, addr6_src, &ph6.saddr) != 1) error(1, errno, "inet_pton6 source ip pseudo"); if (inet_pton(AF_INET6, addr6_dst, &ph6.daddr) != 1) error(1, errno, "inet_pton6 dest ip pseudo"); ph6.protocol = htons(IPPROTO_TCP); ph6.payload_len = htons(sizeof(struct tcphdr) + payload_len); sum = checksum_nofold(&ph6, sizeof(ph6), 0); } else if (proto == PF_INET) { if (inet_pton(AF_INET, addr4_src, &ph4.saddr) != 1) error(1, errno, "inet_pton source ip pseudo"); if (inet_pton(AF_INET, addr4_dst, &ph4.daddr) != 1) error(1, errno, "inet_pton dest ip pseudo"); ph4.protocol = htons(IPPROTO_TCP); ph4.payload_len = htons(sizeof(struct tcphdr) + payload_len); sum = checksum_nofold(&ph4, sizeof(ph4), 0); } return checksum_fold(buf, sizeof(struct tcphdr) + payload_len, sum); } static void read_MAC(uint8_t *mac_addr, char *mac) { if (sscanf(mac, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", &mac_addr[0], &mac_addr[1], &mac_addr[2], &mac_addr[3], &mac_addr[4], &mac_addr[5]) != 6) error(1, 0, "sscanf"); } static void fill_datalinklayer(void *buf) { struct ethhdr *eth = buf; memcpy(eth->h_dest, dst_mac, ETH_ALEN); memcpy(eth->h_source, src_mac, ETH_ALEN); eth->h_proto = ethhdr_proto; } static void fill_networklayer(void *buf, int payload_len) { struct ipv6hdr *ip6h = buf; struct iphdr *iph = buf; if (proto == PF_INET6) { memset(ip6h, 0, sizeof(*ip6h)); ip6h->version = 6; ip6h->payload_len = htons(sizeof(struct tcphdr) + payload_len); ip6h->nexthdr = IPPROTO_TCP; ip6h->hop_limit = 8; if (inet_pton(AF_INET6, addr6_src, &ip6h->saddr) != 1) error(1, errno, "inet_pton source ip6"); if (inet_pton(AF_INET6, addr6_dst, &ip6h->daddr) != 1) error(1, errno, "inet_pton dest ip6"); } else if (proto == PF_INET) { memset(iph, 0, sizeof(*iph)); iph->version = 4; iph->ihl = 5; iph->ttl = 8; iph->protocol = IPPROTO_TCP; iph->tot_len = htons(sizeof(struct tcphdr) + payload_len + sizeof(struct iphdr)); iph->frag_off = htons(0x4000); /* DF = 1, MF = 0 */ if (inet_pton(AF_INET, addr4_src, &iph->saddr) != 1) error(1, errno, "inet_pton source ip"); if (inet_pton(AF_INET, addr4_dst, &iph->daddr) != 1) error(1, errno, "inet_pton dest ip"); iph->check = checksum_fold(buf, sizeof(struct iphdr), 0); } } static void fill_transportlayer(void *buf, int seq_offset, int ack_offset, int payload_len, int fin) { struct tcphdr *tcph = buf; memset(tcph, 0, sizeof(*tcph)); tcph->source = htons(SPORT); tcph->dest = htons(DPORT); tcph->seq = ntohl(START_SEQ + seq_offset); tcph->ack_seq = ntohl(START_ACK + ack_offset); tcph->ack = 1; tcph->fin = fin; tcph->doff = 5; tcph->window = htons(TCP_MAXWIN); tcph->urg_ptr = 0; tcph->check = tcp_checksum(tcph, payload_len); } static void write_packet(int fd, char *buf, int len, struct sockaddr_ll *daddr) { int ret = -1; ret = sendto(fd, buf, len, 0, (struct sockaddr *)daddr, sizeof(*daddr)); if (ret == -1) error(1, errno, "sendto failure"); if (ret != len) error(1, errno, "sendto wrong length"); } static void create_packet(void *buf, int seq_offset, int ack_offset, int payload_len, int fin) { memset(buf, 0, total_hdr_len); memset(buf + total_hdr_len, 'a', payload_len); fill_transportlayer(buf + tcp_offset, seq_offset, ack_offset, payload_len, fin); fill_networklayer(buf + ETH_HLEN, payload_len); fill_datalinklayer(buf); } /* send one extra flag, not first and not last pkt */ static void send_flags(int fd, struct sockaddr_ll *daddr, int psh, int syn, int rst, int urg) { static char flag_buf[MAX_HDR_LEN + PAYLOAD_LEN]; static char buf[MAX_HDR_LEN + PAYLOAD_LEN]; int payload_len, pkt_size, flag, i; struct tcphdr *tcph; payload_len = PAYLOAD_LEN * psh; pkt_size = total_hdr_len + payload_len; flag = NUM_PACKETS / 2; create_packet(flag_buf, flag * payload_len, 0, payload_len, 0); tcph = (struct tcphdr *)(flag_buf + tcp_offset); tcph->psh = psh; tcph->syn = syn; tcph->rst = rst; tcph->urg = urg; tcph->check = 0; tcph->check = tcp_checksum(tcph, payload_len); for (i = 0; i < NUM_PACKETS + 1; i++) { if (i == flag) { write_packet(fd, flag_buf, pkt_size, daddr); continue; } create_packet(buf, i * PAYLOAD_LEN, 0, PAYLOAD_LEN, 0); write_packet(fd, buf, total_hdr_len + PAYLOAD_LEN, daddr); } } /* Test for data of same length, smaller than previous * and of different lengths */ static void send_data_pkts(int fd, struct sockaddr_ll *daddr, int payload_len1, int payload_len2) { static char buf[ETH_HLEN + IP_MAXPACKET]; create_packet(buf, 0, 0, payload_len1, 0); write_packet(fd, buf, total_hdr_len + payload_len1, daddr); create_packet(buf, payload_len1, 0, payload_len2, 0); write_packet(fd, buf, total_hdr_len + payload_len2, daddr); } /* If incoming segments make tracked segment length exceed * legal IP datagram length, do not coalesce */ static void send_large(int fd, struct sockaddr_ll *daddr, int remainder) { static char pkts[NUM_LARGE_PKT][TOTAL_HDR_LEN + MSS]; static char last[TOTAL_HDR_LEN + MSS]; static char new_seg[TOTAL_HDR_LEN + MSS]; int i; for (i = 0; i < NUM_LARGE_PKT; i++) create_packet(pkts[i], i * MSS, 0, MSS, 0); create_packet(last, NUM_LARGE_PKT * MSS, 0, remainder, 0); create_packet(new_seg, (NUM_LARGE_PKT + 1) * MSS, 0, remainder, 0); for (i = 0; i < NUM_LARGE_PKT; i++) write_packet(fd, pkts[i], total_hdr_len + MSS, daddr); write_packet(fd, last, total_hdr_len + remainder, daddr); write_packet(fd, new_seg, total_hdr_len + remainder, daddr); } /* Pure acks and dup acks don't coalesce */ static void send_ack(int fd, struct sockaddr_ll *daddr) { static char buf[MAX_HDR_LEN]; create_packet(buf, 0, 0, 0, 0); write_packet(fd, buf, total_hdr_len, daddr); write_packet(fd, buf, total_hdr_len, daddr); create_packet(buf, 0, 1, 0, 0); write_packet(fd, buf, total_hdr_len, daddr); } static void recompute_packet(char *buf, char *no_ext, int extlen) { struct tcphdr *tcphdr = (struct tcphdr *)(buf + tcp_offset); struct ipv6hdr *ip6h = (struct ipv6hdr *)(buf + ETH_HLEN); struct iphdr *iph = (struct iphdr *)(buf + ETH_HLEN); memmove(buf, no_ext, total_hdr_len); memmove(buf + total_hdr_len + extlen, no_ext + total_hdr_len, PAYLOAD_LEN); tcphdr->doff = tcphdr->doff + (extlen / 4); tcphdr->check = 0; tcphdr->check = tcp_checksum(tcphdr, PAYLOAD_LEN + extlen); if (proto == PF_INET) { iph->tot_len = htons(ntohs(iph->tot_len) + extlen); iph->check = 0; iph->check = checksum_fold(iph, sizeof(struct iphdr), 0); } else { ip6h->payload_len = htons(ntohs(ip6h->payload_len) + extlen); } } static void tcp_write_options(char *buf, int kind, int ts) { struct tcp_option_ts { uint8_t kind; uint8_t len; uint32_t tsval; uint32_t tsecr; } *opt_ts = (void *)buf; struct tcp_option_window { uint8_t kind; uint8_t len; uint8_t shift; } *opt_window = (void *)buf; switch (kind) { case TCPOPT_NOP: buf[0] = TCPOPT_NOP; break; case TCPOPT_WINDOW: memset(opt_window, 0, sizeof(struct tcp_option_window)); opt_window->kind = TCPOPT_WINDOW; opt_window->len = TCPOLEN_WINDOW; opt_window->shift = 0; break; case TCPOPT_TIMESTAMP: memset(opt_ts, 0, sizeof(struct tcp_option_ts)); opt_ts->kind = TCPOPT_TIMESTAMP; opt_ts->len = TCPOLEN_TIMESTAMP; opt_ts->tsval = ts; opt_ts->tsecr = 0; break; default: error(1, 0, "unimplemented TCP option"); break; } } /* TCP with options is always a permutation of {TS, NOP, NOP}. * Implement different orders to verify coalescing stops. */ static void add_standard_tcp_options(char *buf, char *no_ext, int ts, int order) { switch (order) { case 0: tcp_write_options(buf + total_hdr_len, TCPOPT_NOP, 0); tcp_write_options(buf + total_hdr_len + 1, TCPOPT_NOP, 0); tcp_write_options(buf + total_hdr_len + 2 /* two NOP opts */, TCPOPT_TIMESTAMP, ts); break; case 1: tcp_write_options(buf + total_hdr_len, TCPOPT_NOP, 0); tcp_write_options(buf + total_hdr_len + 1, TCPOPT_TIMESTAMP, ts); tcp_write_options(buf + total_hdr_len + 1 + TCPOLEN_TIMESTAMP, TCPOPT_NOP, 0); break; case 2: tcp_write_options(buf + total_hdr_len, TCPOPT_TIMESTAMP, ts); tcp_write_options(buf + total_hdr_len + TCPOLEN_TIMESTAMP + 1, TCPOPT_NOP, 0); tcp_write_options(buf + total_hdr_len + TCPOLEN_TIMESTAMP + 2, TCPOPT_NOP, 0); break; default: error(1, 0, "unknown order"); break; } recompute_packet(buf, no_ext, TCPOLEN_TSTAMP_APPA); } /* Packets with invalid checksum don't coalesce. */ static void send_changed_checksum(int fd, struct sockaddr_ll *daddr) { static char buf[MAX_HDR_LEN + PAYLOAD_LEN]; struct tcphdr *tcph = (struct tcphdr *)(buf + tcp_offset); int pkt_size = total_hdr_len + PAYLOAD_LEN; create_packet(buf, 0, 0, PAYLOAD_LEN, 0); write_packet(fd, buf, pkt_size, daddr); create_packet(buf, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0); tcph->check = tcph->check - 1; write_packet(fd, buf, pkt_size, daddr); } /* Packets with non-consecutive sequence number don't coalesce.*/ static void send_changed_seq(int fd, struct sockaddr_ll *daddr) { static char buf[MAX_HDR_LEN + PAYLOAD_LEN]; struct tcphdr *tcph = (struct tcphdr *)(buf + tcp_offset); int pkt_size = total_hdr_len + PAYLOAD_LEN; create_packet(buf, 0, 0, PAYLOAD_LEN, 0); write_packet(fd, buf, pkt_size, daddr); create_packet(buf, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0); tcph->seq = ntohl(htonl(tcph->seq) + 1); tcph->check = 0; tcph->check = tcp_checksum(tcph, PAYLOAD_LEN); write_packet(fd, buf, pkt_size, daddr); } /* Packet with different timestamp option or different timestamps * don't coalesce. */ static void send_changed_ts(int fd, struct sockaddr_ll *daddr) { static char buf[MAX_HDR_LEN + PAYLOAD_LEN]; static char extpkt[sizeof(buf) + TCPOLEN_TSTAMP_APPA]; int pkt_size = total_hdr_len + PAYLOAD_LEN + TCPOLEN_TSTAMP_APPA; create_packet(buf, 0, 0, PAYLOAD_LEN, 0); add_standard_tcp_options(extpkt, buf, 0, 0); write_packet(fd, extpkt, pkt_size, daddr); create_packet(buf, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0); add_standard_tcp_options(extpkt, buf, 0, 0); write_packet(fd, extpkt, pkt_size, daddr); create_packet(buf, PAYLOAD_LEN * 2, 0, PAYLOAD_LEN, 0); add_standard_tcp_options(extpkt, buf, 100, 0); write_packet(fd, extpkt, pkt_size, daddr); create_packet(buf, PAYLOAD_LEN * 3, 0, PAYLOAD_LEN, 0); add_standard_tcp_options(extpkt, buf, 100, 1); write_packet(fd, extpkt, pkt_size, daddr); create_packet(buf, PAYLOAD_LEN * 4, 0, PAYLOAD_LEN, 0); add_standard_tcp_options(extpkt, buf, 100, 2); write_packet(fd, extpkt, pkt_size, daddr); } /* Packet with different tcp options don't coalesce. */ static void send_diff_opt(int fd, struct sockaddr_ll *daddr) { static char buf[MAX_HDR_LEN + PAYLOAD_LEN]; static char extpkt1[sizeof(buf) + TCPOLEN_TSTAMP_APPA]; static char extpkt2[sizeof(buf) + TCPOLEN_MAXSEG]; int extpkt1_size = total_hdr_len + PAYLOAD_LEN + TCPOLEN_TSTAMP_APPA; int extpkt2_size = total_hdr_len + PAYLOAD_LEN + TCPOLEN_MAXSEG; create_packet(buf, 0, 0, PAYLOAD_LEN, 0); add_standard_tcp_options(extpkt1, buf, 0, 0); write_packet(fd, extpkt1, extpkt1_size, daddr); create_packet(buf, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0); add_standard_tcp_options(extpkt1, buf, 0, 0); write_packet(fd, extpkt1, extpkt1_size, daddr); create_packet(buf, PAYLOAD_LEN * 2, 0, PAYLOAD_LEN, 0); tcp_write_options(extpkt2 + MAX_HDR_LEN, TCPOPT_NOP, 0); tcp_write_options(extpkt2 + MAX_HDR_LEN + 1, TCPOPT_WINDOW, 0); recompute_packet(extpkt2, buf, TCPOLEN_WINDOW + 1); write_packet(fd, extpkt2, extpkt2_size, daddr); } static void add_ipv4_ts_option(void *buf, void *optpkt) { struct ip_timestamp *ts = (struct ip_timestamp *)(optpkt + tcp_offset); int optlen = sizeof(struct ip_timestamp); struct iphdr *iph; if (optlen % 4) error(1, 0, "ipv4 timestamp length is not a multiple of 4B"); ts->ipt_code = IPOPT_TS; ts->ipt_len = optlen; ts->ipt_ptr = 5; ts->ipt_flg = IPOPT_TS_TSONLY; memcpy(optpkt, buf, tcp_offset); memcpy(optpkt + tcp_offset + optlen, buf + tcp_offset, sizeof(struct tcphdr) + PAYLOAD_LEN); iph = (struct iphdr *)(optpkt + ETH_HLEN); iph->ihl = 5 + (optlen / 4); iph->tot_len = htons(ntohs(iph->tot_len) + optlen); iph->check = 0; iph->check = checksum_fold(iph, sizeof(struct iphdr) + optlen, 0); } static void add_ipv6_exthdr(void *buf, void *optpkt, __u8 exthdr_type, char *ext_payload) { struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr *)(optpkt + tcp_offset); struct ipv6hdr *iph = (struct ipv6hdr *)(optpkt + ETH_HLEN); char *exthdr_payload_start = (char *)(exthdr + 1); exthdr->hdrlen = 0; exthdr->nexthdr = IPPROTO_TCP; memcpy(exthdr_payload_start, ext_payload, MIN_EXTHDR_SIZE - sizeof(*exthdr)); memcpy(optpkt, buf, tcp_offset); memcpy(optpkt + tcp_offset + MIN_EXTHDR_SIZE, buf + tcp_offset, sizeof(struct tcphdr) + PAYLOAD_LEN); iph->nexthdr = exthdr_type; iph->payload_len = htons(ntohs(iph->payload_len) + MIN_EXTHDR_SIZE); } static void fix_ip4_checksum(struct iphdr *iph) { iph->check = 0; iph->check = checksum_fold(iph, sizeof(struct iphdr), 0); } static void send_flush_id_case(int fd, struct sockaddr_ll *daddr, int tcase) { static char buf1[MAX_HDR_LEN + PAYLOAD_LEN]; static char buf2[MAX_HDR_LEN + PAYLOAD_LEN]; static char buf3[MAX_HDR_LEN + PAYLOAD_LEN]; bool send_three = false; struct iphdr *iph1; struct iphdr *iph2; struct iphdr *iph3; iph1 = (struct iphdr *)(buf1 + ETH_HLEN); iph2 = (struct iphdr *)(buf2 + ETH_HLEN); iph3 = (struct iphdr *)(buf3 + ETH_HLEN); create_packet(buf1, 0, 0, PAYLOAD_LEN, 0); create_packet(buf2, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0); create_packet(buf3, PAYLOAD_LEN * 2, 0, PAYLOAD_LEN, 0); switch (tcase) { case 0: /* DF=1, Incrementing - should coalesce */ iph1->frag_off |= htons(IP_DF); iph1->id = htons(8); iph2->frag_off |= htons(IP_DF); iph2->id = htons(9); break; case 1: /* DF=1, Fixed - should coalesce */ iph1->frag_off |= htons(IP_DF); iph1->id = htons(8); iph2->frag_off |= htons(IP_DF); iph2->id = htons(8); break; case 2: /* DF=0, Incrementing - should coalesce */ iph1->frag_off &= ~htons(IP_DF); iph1->id = htons(8); iph2->frag_off &= ~htons(IP_DF); iph2->id = htons(9); break; case 3: /* DF=0, Fixed - should not coalesce */ iph1->frag_off &= ~htons(IP_DF); iph1->id = htons(8); iph2->frag_off &= ~htons(IP_DF); iph2->id = htons(8); break; case 4: /* DF=1, two packets incrementing, and one fixed - should * coalesce only the first two packets */ iph1->frag_off |= htons(IP_DF); iph1->id = htons(8); iph2->frag_off |= htons(IP_DF); iph2->id = htons(9); iph3->frag_off |= htons(IP_DF); iph3->id = htons(9); send_three = true; break; case 5: /* DF=1, two packets fixed, and one incrementing - should * coalesce only the first two packets */ iph1->frag_off |= htons(IP_DF); iph1->id = htons(8); iph2->frag_off |= htons(IP_DF); iph2->id = htons(8); iph3->frag_off |= htons(IP_DF); iph3->id = htons(9); send_three = true; break; } fix_ip4_checksum(iph1); fix_ip4_checksum(iph2); write_packet(fd, buf1, total_hdr_len + PAYLOAD_LEN, daddr); write_packet(fd, buf2, total_hdr_len + PAYLOAD_LEN, daddr); if (send_three) { fix_ip4_checksum(iph3); write_packet(fd, buf3, total_hdr_len + PAYLOAD_LEN, daddr); } } static void test_flush_id(int fd, struct sockaddr_ll *daddr, char *fin_pkt) { for (int i = 0; i < num_flush_id_cases; i++) { sleep(1); send_flush_id_case(fd, daddr, i); sleep(1); write_packet(fd, fin_pkt, total_hdr_len, daddr); } } static void send_ipv6_exthdr(int fd, struct sockaddr_ll *daddr, char *ext_data1, char *ext_data2) { static char buf[MAX_HDR_LEN + PAYLOAD_LEN]; static char exthdr_pck[sizeof(buf) + MIN_EXTHDR_SIZE]; create_packet(buf, 0, 0, PAYLOAD_LEN, 0); add_ipv6_exthdr(buf, exthdr_pck, IPPROTO_HOPOPTS, ext_data1); write_packet(fd, exthdr_pck, total_hdr_len + PAYLOAD_LEN + MIN_EXTHDR_SIZE, daddr); create_packet(buf, PAYLOAD_LEN * 1, 0, PAYLOAD_LEN, 0); add_ipv6_exthdr(buf, exthdr_pck, IPPROTO_HOPOPTS, ext_data2); write_packet(fd, exthdr_pck, total_hdr_len + PAYLOAD_LEN + MIN_EXTHDR_SIZE, daddr); } /* IPv4 options shouldn't coalesce */ static void send_ip_options(int fd, struct sockaddr_ll *daddr) { static char buf[MAX_HDR_LEN + PAYLOAD_LEN]; static char optpkt[sizeof(buf) + sizeof(struct ip_timestamp)]; int optlen = sizeof(struct ip_timestamp); int pkt_size = total_hdr_len + PAYLOAD_LEN + optlen; create_packet(buf, 0, 0, PAYLOAD_LEN, 0); write_packet(fd, buf, total_hdr_len + PAYLOAD_LEN, daddr); create_packet(buf, PAYLOAD_LEN * 1, 0, PAYLOAD_LEN, 0); add_ipv4_ts_option(buf, optpkt); write_packet(fd, optpkt, pkt_size, daddr); create_packet(buf, PAYLOAD_LEN * 2, 0, PAYLOAD_LEN, 0); write_packet(fd, buf, total_hdr_len + PAYLOAD_LEN, daddr); } /* IPv4 fragments shouldn't coalesce */ static void send_fragment4(int fd, struct sockaddr_ll *daddr) { static char buf[IP_MAXPACKET]; struct iphdr *iph = (struct iphdr *)(buf + ETH_HLEN); int pkt_size = total_hdr_len + PAYLOAD_LEN; create_packet(buf, 0, 0, PAYLOAD_LEN, 0); write_packet(fd, buf, pkt_size, daddr); /* Once fragmented, packet would retain the total_len. * Tcp header is prepared as if rest of data is in follow-up frags, * but follow up frags aren't actually sent. */ memset(buf + total_hdr_len, 'a', PAYLOAD_LEN * 2); fill_transportlayer(buf + tcp_offset, PAYLOAD_LEN, 0, PAYLOAD_LEN * 2, 0); fill_networklayer(buf + ETH_HLEN, PAYLOAD_LEN); fill_datalinklayer(buf); iph->frag_off = htons(0x6000); // DF = 1, MF = 1 iph->check = 0; iph->check = checksum_fold(iph, sizeof(struct iphdr), 0); write_packet(fd, buf, pkt_size, daddr); } /* IPv4 packets with different ttl don't coalesce.*/ static void send_changed_ttl(int fd, struct sockaddr_ll *daddr) { int pkt_size = total_hdr_len + PAYLOAD_LEN; static char buf[MAX_HDR_LEN + PAYLOAD_LEN]; struct iphdr *iph = (struct iphdr *)(buf + ETH_HLEN); create_packet(buf, 0, 0, PAYLOAD_LEN, 0); write_packet(fd, buf, pkt_size, daddr); create_packet(buf, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0); iph->ttl = 7; iph->check = 0; iph->check = checksum_fold(iph, sizeof(struct iphdr), 0); write_packet(fd, buf, pkt_size, daddr); } /* Packets with different tos don't coalesce.*/ static void send_changed_tos(int fd, struct sockaddr_ll *daddr) { int pkt_size = total_hdr_len + PAYLOAD_LEN; static char buf[MAX_HDR_LEN + PAYLOAD_LEN]; struct iphdr *iph = (struct iphdr *)(buf + ETH_HLEN); struct ipv6hdr *ip6h = (struct ipv6hdr *)(buf + ETH_HLEN); create_packet(buf, 0, 0, PAYLOAD_LEN, 0); write_packet(fd, buf, pkt_size, daddr); create_packet(buf, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0); if (proto == PF_INET) { iph->tos = 1; iph->check = 0; iph->check = checksum_fold(iph, sizeof(struct iphdr), 0); } else if (proto == PF_INET6) { ip6h->priority = 0xf; } write_packet(fd, buf, pkt_size, daddr); } /* Packets with different ECN don't coalesce.*/ static void send_changed_ECN(int fd, struct sockaddr_ll *daddr) { int pkt_size = total_hdr_len + PAYLOAD_LEN; static char buf[MAX_HDR_LEN + PAYLOAD_LEN]; struct iphdr *iph = (struct iphdr *)(buf + ETH_HLEN); create_packet(buf, 0, 0, PAYLOAD_LEN, 0); write_packet(fd, buf, pkt_size, daddr); create_packet(buf, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0); if (proto == PF_INET) { buf[ETH_HLEN + 1] ^= 0x2; // ECN set to 10 iph->check = 0; iph->check = checksum_fold(iph, sizeof(struct iphdr), 0); } else { buf[ETH_HLEN + 1] ^= 0x20; // ECN set to 10 } write_packet(fd, buf, pkt_size, daddr); } /* IPv6 fragments and packets with extensions don't coalesce.*/ static void send_fragment6(int fd, struct sockaddr_ll *daddr) { static char buf[MAX_HDR_LEN + PAYLOAD_LEN]; static char extpkt[MAX_HDR_LEN + PAYLOAD_LEN + sizeof(struct ip6_frag)]; struct ipv6hdr *ip6h = (struct ipv6hdr *)(buf + ETH_HLEN); struct ip6_frag *frag = (void *)(extpkt + tcp_offset); int extlen = sizeof(struct ip6_frag); int bufpkt_len = total_hdr_len + PAYLOAD_LEN; int extpkt_len = bufpkt_len + extlen; int i; for (i = 0; i < 2; i++) { create_packet(buf, PAYLOAD_LEN * i, 0, PAYLOAD_LEN, 0); write_packet(fd, buf, bufpkt_len, daddr); } sleep(1); create_packet(buf, PAYLOAD_LEN * 2, 0, PAYLOAD_LEN, 0); memset(extpkt, 0, extpkt_len); ip6h->nexthdr = IPPROTO_FRAGMENT; ip6h->payload_len = htons(ntohs(ip6h->payload_len) + extlen); frag->ip6f_nxt = IPPROTO_TCP; memcpy(extpkt, buf, tcp_offset); memcpy(extpkt + tcp_offset + extlen, buf + tcp_offset, sizeof(struct tcphdr) + PAYLOAD_LEN); write_packet(fd, extpkt, extpkt_len, daddr); create_packet(buf, PAYLOAD_LEN * 3, 0, PAYLOAD_LEN, 0); write_packet(fd, buf, bufpkt_len, daddr); } static void bind_packetsocket(int fd) { struct sockaddr_ll daddr = {}; daddr.sll_family = AF_PACKET; daddr.sll_protocol = ethhdr_proto; daddr.sll_ifindex = if_nametoindex(ifname); if (daddr.sll_ifindex == 0) error(1, errno, "if_nametoindex"); if (bind(fd, (void *)&daddr, sizeof(daddr)) < 0) error(1, errno, "could not bind socket"); } static void set_timeout(int fd) { struct timeval timeout; timeout.tv_sec = 3; timeout.tv_usec = 0; if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, (char *)&timeout, sizeof(timeout)) < 0) error(1, errno, "cannot set timeout, setsockopt failed"); } static void check_recv_pkts(int fd, int *correct_payload, int correct_num_pkts) { static char buffer[IP_MAXPACKET + ETH_HLEN + 1]; struct iphdr *iph = (struct iphdr *)(buffer + ETH_HLEN); struct ipv6hdr *ip6h = (struct ipv6hdr *)(buffer + ETH_HLEN); struct tcphdr *tcph; bool bad_packet = false; int tcp_ext_len = 0; int ip_ext_len = 0; int pkt_size = -1; int data_len = 0; int num_pkt = 0; int i; vlog("Expected {"); for (i = 0; i < correct_num_pkts; i++) vlog("%d ", correct_payload[i]); vlog("}, Total %d packets\nReceived {", correct_num_pkts); while (1) { ip_ext_len = 0; pkt_size = recv(fd, buffer, IP_MAXPACKET + ETH_HLEN + 1, 0); if (pkt_size < 0) error(1, errno, "could not receive"); if (iph->version == 4) ip_ext_len = (iph->ihl - 5) * 4; else if (ip6h->version == 6 && ip6h->nexthdr != IPPROTO_TCP) ip_ext_len = MIN_EXTHDR_SIZE; tcph = (struct tcphdr *)(buffer + tcp_offset + ip_ext_len); if (tcph->fin) break; tcp_ext_len = (tcph->doff - 5) * 4; data_len = pkt_size - total_hdr_len - tcp_ext_len - ip_ext_len; /* Min ethernet frame payload is 46(ETH_ZLEN - ETH_HLEN) by RFC 802.3. * Ipv4/tcp packets without at least 6 bytes of data will be padded. * Packet sockets are protocol agnostic, and will not trim the padding. */ if (pkt_size == ETH_ZLEN && iph->version == 4) { data_len = ntohs(iph->tot_len) - sizeof(struct tcphdr) - sizeof(struct iphdr); } vlog("%d ", data_len); if (data_len != correct_payload[num_pkt]) { vlog("[!=%d]", correct_payload[num_pkt]); bad_packet = true; } num_pkt++; } vlog("}, Total %d packets.\n", num_pkt); if (num_pkt != correct_num_pkts) error(1, 0, "incorrect number of packets"); if (bad_packet) error(1, 0, "incorrect packet geometry"); printf("Test succeeded\n\n"); } static void gro_sender(void) { static char fin_pkt[MAX_HDR_LEN]; struct sockaddr_ll daddr = {}; int txfd = -1; txfd = socket(PF_PACKET, SOCK_RAW, IPPROTO_RAW); if (txfd < 0) error(1, errno, "socket creation"); memset(&daddr, 0, sizeof(daddr)); daddr.sll_ifindex = if_nametoindex(ifname); if (daddr.sll_ifindex == 0) error(1, errno, "if_nametoindex"); daddr.sll_family = AF_PACKET; memcpy(daddr.sll_addr, dst_mac, ETH_ALEN); daddr.sll_halen = ETH_ALEN; create_packet(fin_pkt, PAYLOAD_LEN * 2, 0, 0, 1); if (strcmp(testname, "data") == 0) { send_data_pkts(txfd, &daddr, PAYLOAD_LEN, PAYLOAD_LEN); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); send_data_pkts(txfd, &daddr, PAYLOAD_LEN, PAYLOAD_LEN / 2); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); send_data_pkts(txfd, &daddr, PAYLOAD_LEN / 2, PAYLOAD_LEN); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); } else if (strcmp(testname, "ack") == 0) { send_ack(txfd, &daddr); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); } else if (strcmp(testname, "flags") == 0) { send_flags(txfd, &daddr, 1, 0, 0, 0); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); send_flags(txfd, &daddr, 0, 1, 0, 0); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); send_flags(txfd, &daddr, 0, 0, 1, 0); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); send_flags(txfd, &daddr, 0, 0, 0, 1); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); } else if (strcmp(testname, "tcp") == 0) { send_changed_checksum(txfd, &daddr); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); send_changed_seq(txfd, &daddr); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); send_changed_ts(txfd, &daddr); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); send_diff_opt(txfd, &daddr); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); } else if (strcmp(testname, "ip") == 0) { send_changed_ECN(txfd, &daddr); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); send_changed_tos(txfd, &daddr); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); if (proto == PF_INET) { /* Modified packets may be received out of order. * Sleep function added to enforce test boundaries * so that fin pkts are not received prior to other pkts. */ sleep(1); send_changed_ttl(txfd, &daddr); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); sleep(1); send_ip_options(txfd, &daddr); sleep(1); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); sleep(1); send_fragment4(txfd, &daddr); sleep(1); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); test_flush_id(txfd, &daddr, fin_pkt); } else if (proto == PF_INET6) { sleep(1); send_fragment6(txfd, &daddr); sleep(1); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); sleep(1); /* send IPv6 packets with ext header with same payload */ send_ipv6_exthdr(txfd, &daddr, EXT_PAYLOAD_1, EXT_PAYLOAD_1); sleep(1); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); sleep(1); /* send IPv6 packets with ext header with different payload */ send_ipv6_exthdr(txfd, &daddr, EXT_PAYLOAD_1, EXT_PAYLOAD_2); sleep(1); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); } } else if (strcmp(testname, "large") == 0) { /* 20 is the difference between min iphdr size * and min ipv6hdr size. Like MAX_HDR_SIZE, * MAX_PAYLOAD is defined with the larger header of the two. */ int offset = proto == PF_INET ? 20 : 0; int remainder = (MAX_PAYLOAD + offset) % MSS; send_large(txfd, &daddr, remainder); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); send_large(txfd, &daddr, remainder + 1); write_packet(txfd, fin_pkt, total_hdr_len, &daddr); } else { error(1, 0, "Unknown testcase"); } if (close(txfd)) error(1, errno, "socket close"); } static void gro_receiver(void) { static int correct_payload[NUM_PACKETS]; int rxfd = -1; rxfd = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_NONE)); if (rxfd < 0) error(1, 0, "socket creation"); setup_sock_filter(rxfd); set_timeout(rxfd); bind_packetsocket(rxfd); memset(correct_payload, 0, sizeof(correct_payload)); if (strcmp(testname, "data") == 0) { printf("pure data packet of same size: "); correct_payload[0] = PAYLOAD_LEN * 2; check_recv_pkts(rxfd, correct_payload, 1); printf("large data packets followed by a smaller one: "); correct_payload[0] = PAYLOAD_LEN * 1.5; check_recv_pkts(rxfd, correct_payload, 1); printf("small data packets followed by a larger one: "); correct_payload[0] = PAYLOAD_LEN / 2; correct_payload[1] = PAYLOAD_LEN; check_recv_pkts(rxfd, correct_payload, 2); } else if (strcmp(testname, "ack") == 0) { printf("duplicate ack and pure ack: "); check_recv_pkts(rxfd, correct_payload, 3); } else if (strcmp(testname, "flags") == 0) { correct_payload[0] = PAYLOAD_LEN * 3; correct_payload[1] = PAYLOAD_LEN * 2; printf("psh flag ends coalescing: "); check_recv_pkts(rxfd, correct_payload, 2); correct_payload[0] = PAYLOAD_LEN * 2; correct_payload[1] = 0; correct_payload[2] = PAYLOAD_LEN * 2; printf("syn flag ends coalescing: "); check_recv_pkts(rxfd, correct_payload, 3); printf("rst flag ends coalescing: "); check_recv_pkts(rxfd, correct_payload, 3); printf("urg flag ends coalescing: "); check_recv_pkts(rxfd, correct_payload, 3); } else if (strcmp(testname, "tcp") == 0) { correct_payload[0] = PAYLOAD_LEN; correct_payload[1] = PAYLOAD_LEN; correct_payload[2] = PAYLOAD_LEN; correct_payload[3] = PAYLOAD_LEN; printf("changed checksum does not coalesce: "); check_recv_pkts(rxfd, correct_payload, 2); printf("Wrong Seq number doesn't coalesce: "); check_recv_pkts(rxfd, correct_payload, 2); printf("Different timestamp doesn't coalesce: "); correct_payload[0] = PAYLOAD_LEN * 2; check_recv_pkts(rxfd, correct_payload, 4); printf("Different options doesn't coalesce: "); correct_payload[0] = PAYLOAD_LEN * 2; check_recv_pkts(rxfd, correct_payload, 2); } else if (strcmp(testname, "ip") == 0) { correct_payload[0] = PAYLOAD_LEN; correct_payload[1] = PAYLOAD_LEN; printf("different ECN doesn't coalesce: "); check_recv_pkts(rxfd, correct_payload, 2); printf("different tos doesn't coalesce: "); check_recv_pkts(rxfd, correct_payload, 2); if (proto == PF_INET) { printf("different ttl doesn't coalesce: "); check_recv_pkts(rxfd, correct_payload, 2); printf("ip options doesn't coalesce: "); correct_payload[2] = PAYLOAD_LEN; check_recv_pkts(rxfd, correct_payload, 3); printf("fragmented ip4 doesn't coalesce: "); check_recv_pkts(rxfd, correct_payload, 2); /* is_atomic checks */ printf("DF=1, Incrementing - should coalesce: "); correct_payload[0] = PAYLOAD_LEN * 2; check_recv_pkts(rxfd, correct_payload, 1); printf("DF=1, Fixed - should coalesce: "); correct_payload[0] = PAYLOAD_LEN * 2; check_recv_pkts(rxfd, correct_payload, 1); printf("DF=0, Incrementing - should coalesce: "); correct_payload[0] = PAYLOAD_LEN * 2; check_recv_pkts(rxfd, correct_payload, 1); printf("DF=0, Fixed - should not coalesce: "); correct_payload[0] = PAYLOAD_LEN; correct_payload[1] = PAYLOAD_LEN; check_recv_pkts(rxfd, correct_payload, 2); printf("DF=1, 2 Incrementing and one fixed - should coalesce only first 2 packets: "); correct_payload[0] = PAYLOAD_LEN * 2; correct_payload[1] = PAYLOAD_LEN; check_recv_pkts(rxfd, correct_payload, 2); printf("DF=1, 2 Fixed and one incrementing - should coalesce only first 2 packets: "); correct_payload[0] = PAYLOAD_LEN * 2; correct_payload[1] = PAYLOAD_LEN; check_recv_pkts(rxfd, correct_payload, 2); } else if (proto == PF_INET6) { /* GRO doesn't check for ipv6 hop limit when flushing. * Hence no corresponding test to the ipv4 case. */ printf("fragmented ip6 doesn't coalesce: "); correct_payload[0] = PAYLOAD_LEN * 2; correct_payload[1] = PAYLOAD_LEN; correct_payload[2] = PAYLOAD_LEN; check_recv_pkts(rxfd, correct_payload, 3); printf("ipv6 with ext header does coalesce: "); correct_payload[0] = PAYLOAD_LEN * 2; check_recv_pkts(rxfd, correct_payload, 1); printf("ipv6 with ext header with different payloads doesn't coalesce: "); correct_payload[0] = PAYLOAD_LEN; correct_payload[1] = PAYLOAD_LEN; check_recv_pkts(rxfd, correct_payload, 2); } } else if (strcmp(testname, "large") == 0) { int offset = proto == PF_INET ? 20 : 0; int remainder = (MAX_PAYLOAD + offset) % MSS; correct_payload[0] = (MAX_PAYLOAD + offset); correct_payload[1] = remainder; printf("Shouldn't coalesce if exceed IP max pkt size: "); check_recv_pkts(rxfd, correct_payload, 2); /* last segment sent individually, doesn't start new segment */ correct_payload[0] = correct_payload[0] - remainder; correct_payload[1] = remainder + 1; correct_payload[2] = remainder + 1; check_recv_pkts(rxfd, correct_payload, 3); } else { error(1, 0, "Test case error, should never trigger"); } if (close(rxfd)) error(1, 0, "socket close"); } static void parse_args(int argc, char **argv) { static const struct option opts[] = { { "daddr", required_argument, NULL, 'd' }, { "dmac", required_argument, NULL, 'D' }, { "iface", required_argument, NULL, 'i' }, { "ipv4", no_argument, NULL, '4' }, { "ipv6", no_argument, NULL, '6' }, { "rx", no_argument, NULL, 'r' }, { "saddr", required_argument, NULL, 's' }, { "smac", required_argument, NULL, 'S' }, { "test", required_argument, NULL, 't' }, { "verbose", no_argument, NULL, 'v' }, { 0, 0, 0, 0 } }; int c; while ((c = getopt_long(argc, argv, "46d:D:i:rs:S:t:v", opts, NULL)) != -1) { switch (c) { case '4': proto = PF_INET; ethhdr_proto = htons(ETH_P_IP); break; case '6': proto = PF_INET6; ethhdr_proto = htons(ETH_P_IPV6); break; case 'd': addr4_dst = addr6_dst = optarg; break; case 'D': dmac = optarg; break; case 'i': ifname = optarg; break; case 'r': tx_socket = false; break; case 's': addr4_src = addr6_src = optarg; break; case 'S': smac = optarg; break; case 't': testname = optarg; break; case 'v': verbose = true; break; default: error(1, 0, "%s invalid option %c\n", __func__, c); break; } } } int main(int argc, char **argv) { parse_args(argc, argv); if (proto == PF_INET) { tcp_offset = ETH_HLEN + sizeof(struct iphdr); total_hdr_len = tcp_offset + sizeof(struct tcphdr); } else if (proto == PF_INET6) { tcp_offset = ETH_HLEN + sizeof(struct ipv6hdr); total_hdr_len = MAX_HDR_LEN; } else { error(1, 0, "Protocol family is not ipv4 or ipv6"); } read_MAC(src_mac, smac); read_MAC(dst_mac, dmac); if (tx_socket) gro_sender(); else gro_receiver(); fprintf(stderr, "Gro::%s test passed.\n", testname); return 0; }