diff options
| -rw-r--r-- | tcp.c | 529 | ||||
| -rw-r--r-- | util.h | 3 |
2 files changed, 264 insertions, 268 deletions
@@ -318,39 +318,14 @@ /* MSS rounding: see SET_MSS() */ #define MSS_DEFAULT 536 - -struct tcp4_l2_head { /* For MSS4 macro: keep in sync with tcp4_l2_buf_t */ -#ifdef __AVX2__ - uint8_t pad[26]; -#else - uint8_t pad[2]; -#endif - struct tap_hdr taph; - struct iphdr iph; - struct tcphdr th; -#ifdef __AVX2__ -} __attribute__ ((packed, aligned(32))); -#else -} __attribute__ ((packed, aligned(__alignof__(unsigned int)))); -#endif - -struct tcp6_l2_head { /* For MSS6 macro: keep in sync with tcp6_l2_buf_t */ -#ifdef __AVX2__ - uint8_t pad[14]; -#else - uint8_t pad[2]; -#endif - struct tap_hdr taph; - struct ipv6hdr ip6h; - struct tcphdr th; -#ifdef __AVX2__ -} __attribute__ ((packed, aligned(32))); -#else -} __attribute__ ((packed, aligned(__alignof__(unsigned int)))); -#endif - -#define MSS4 ROUND_DOWN(USHRT_MAX - sizeof(struct tcp4_l2_head), 4) -#define MSS6 ROUND_DOWN(USHRT_MAX - sizeof(struct tcp6_l2_head), 4) +#define MSS4 ROUND_DOWN(IP_MAX_MTU - \ + sizeof(struct tcphdr) - \ + sizeof(struct iphdr), \ + sizeof(uint32_t)) +#define MSS6 ROUND_DOWN(IP_MAX_MTU - \ + sizeof(struct tcphdr) - \ + sizeof(struct ipv6hdr), \ + sizeof(uint32_t)) #define WINDOW_DEFAULT 14600 /* RFC 6928 */ #ifdef HAS_SND_WND @@ -445,133 +420,107 @@ struct tcp_buf_seq_update { }; /* Static buffers */ - /** - * tcp4_l2_buf_t - Pre-cooked IPv4 packet buffers for tap connections - * @pad: Align TCP header to 32 bytes, for AVX2 checksum calculation only - * @taph: Tap-level headers (partially pre-filled) - * @iph: Pre-filled IP header (except for tot_len and saddr) - * @uh: Headroom for TCP header - * @data: Storage for TCP payload + * struct tcp_payload_t - TCP header and data to send segments with payload + * @th: TCP header + * @data: TCP data */ -static struct tcp4_l2_buf_t { -#ifdef __AVX2__ - uint8_t pad[26]; /* 0, align th to 32 bytes */ -#else - uint8_t pad[2]; /* align iph to 4 bytes 0 */ -#endif - struct tap_hdr taph; /* 26 2 */ - struct iphdr iph; /* 44 20 */ - struct tcphdr th; /* 64 40 */ - uint8_t data[MSS4]; /* 84 60 */ - /* 65536 65532 */ +struct tcp_payload_t { + struct tcphdr th; + uint8_t data[IP_MAX_MTU - sizeof(struct tcphdr)]; #ifdef __AVX2__ -} __attribute__ ((packed, aligned(32))) +} __attribute__ ((packed, aligned(32))); /* For AVX2 checksum routines */ #else -} __attribute__ ((packed, aligned(__alignof__(unsigned int)))) +} __attribute__ ((packed, aligned(__alignof__(unsigned int)))); #endif -tcp4_l2_buf[TCP_FRAMES_MEM]; - -static struct tcp_buf_seq_update tcp4_l2_buf_seq_update[TCP_FRAMES_MEM]; - -static unsigned int tcp4_l2_buf_used; /** - * tcp6_l2_buf_t - Pre-cooked IPv6 packet buffers for tap connections - * @pad: Align IPv6 header for checksum calculation to 32B (AVX2) or 4B - * @taph: Tap-level headers (partially pre-filled) - * @ip6h: Pre-filled IP header (except for payload_len and addresses) - * @th: Headroom for TCP header - * @data: Storage for TCP payload + * struct tcp_flags_t - TCP header and data to send zero-length + * segments (flags) + * @th: TCP header + * @opts TCP options */ -struct tcp6_l2_buf_t { -#ifdef __AVX2__ - uint8_t pad[14]; /* 0 align ip6h to 32 bytes */ -#else - uint8_t pad[2]; /* align ip6h to 4 bytes 0 */ -#endif - struct tap_hdr taph; /* 14 2 */ - struct ipv6hdr ip6h; /* 32 20 */ - struct tcphdr th; /* 72 60 */ - uint8_t data[MSS6]; /* 92 80 */ - /* 65536 65532 */ +struct tcp_flags_t { + struct tcphdr th; + char opts[OPT_MSS_LEN + OPT_WS_LEN + 1]; #ifdef __AVX2__ -} __attribute__ ((packed, aligned(32))) +} __attribute__ ((packed, aligned(32))); #else -} __attribute__ ((packed, aligned(__alignof__(unsigned int)))) +} __attribute__ ((packed, aligned(__alignof__(unsigned int)))); #endif -tcp6_l2_buf[TCP_FRAMES_MEM]; -static struct tcp_buf_seq_update tcp6_l2_buf_seq_update[TCP_FRAMES_MEM]; +/* Ethernet header for IPv4 frames */ +static struct ethhdr tcp4_eth_src; + +static uint32_t tcp4_payload_vnet_len[TCP_FRAMES_MEM]; +/* IPv4 headers */ +static struct iphdr tcp4_payload_ip[TCP_FRAMES_MEM]; +/* TCP segments with payload for IPv4 frames */ +static struct tcp_payload_t tcp4_payload[TCP_FRAMES_MEM]; + +static_assert(MSS4 <= sizeof(tcp4_payload[0].data), "MSS4 is greater than 65516"); + +static struct tcp_buf_seq_update tcp4_seq_update[TCP_FRAMES_MEM]; +static unsigned int tcp4_payload_used; + +static uint32_t tcp4_flags_vnet_len[TCP_FRAMES_MEM]; +/* IPv4 headers for TCP segment without payload */ +static struct iphdr tcp4_flags_ip[TCP_FRAMES_MEM]; +/* TCP segments without payload for IPv4 frames */ +static struct tcp_flags_t tcp4_flags[TCP_FRAMES_MEM]; + +static unsigned int tcp4_flags_used; + +/* Ethernet header for IPv6 frames */ +static struct ethhdr tcp6_eth_src; + +static uint32_t tcp6_payload_vnet_len[TCP_FRAMES_MEM]; +/* IPv6 headers */ +static struct ipv6hdr tcp6_payload_ip[TCP_FRAMES_MEM]; +/* TCP headers and data for IPv6 frames */ +static struct tcp_payload_t tcp6_payload[TCP_FRAMES_MEM]; -static unsigned int tcp6_l2_buf_used; +static_assert(MSS6 <= sizeof(tcp6_payload[0].data), "MSS6 is greater than 65516"); + +static struct tcp_buf_seq_update tcp6_seq_update[TCP_FRAMES_MEM]; +static unsigned int tcp6_payload_used; + +static uint32_t tcp6_flags_vnet_len[TCP_FRAMES_MEM]; +/* IPv6 headers for TCP segment without payload */ +static struct ipv6hdr tcp6_flags_ip[TCP_FRAMES_MEM]; +/* TCP segment without payload for IPv6 frames */ +static struct tcp_flags_t tcp6_flags[TCP_FRAMES_MEM]; + +static unsigned int tcp6_flags_used; /* recvmsg()/sendmsg() data for tap */ static char tcp_buf_discard [MAX_WINDOW]; static struct iovec iov_sock [TCP_FRAMES_MEM + 1]; -static struct iovec tcp4_l2_iov [TCP_FRAMES_MEM]; -static struct iovec tcp6_l2_iov [TCP_FRAMES_MEM]; -static struct iovec tcp4_l2_flags_iov [TCP_FRAMES_MEM]; -static struct iovec tcp6_l2_flags_iov [TCP_FRAMES_MEM]; +/* + * enum tcp_iov_parts - I/O vector parts for one TCP frame + * @TCP_IOV_VLEN virtio net header + * @TCP_IOV_ETH Ethernet header + * @TCP_IOV_IP IP (v4/v6) header + * @TCP_IOV_PAYLOAD IP payload (TCP header + data) + * @TCP_NUM_IOVS the number of entries in the iovec array + */ +enum tcp_iov_parts { + TCP_IOV_VLEN = 0, + TCP_IOV_ETH = 1, + TCP_IOV_IP = 2, + TCP_IOV_PAYLOAD = 3, + TCP_NUM_IOVS +}; + +static struct iovec tcp4_l2_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS]; +static struct iovec tcp6_l2_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS]; +static struct iovec tcp4_l2_flags_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS]; +static struct iovec tcp6_l2_flags_iov [TCP_FRAMES_MEM][TCP_NUM_IOVS]; /* sendmsg() to socket */ static struct iovec tcp_iov [UIO_MAXIOV]; -/** - * tcp4_l2_flags_buf_t - IPv4 packet buffers for segments without data (flags) - * @pad: Align TCP header to 32 bytes, for AVX2 checksum calculation only - * @taph: Tap-level headers (partially pre-filled) - * @iph: Pre-filled IP header (except for tot_len and saddr) - * @th: Headroom for TCP header - * @opts: Headroom for TCP options - */ -static struct tcp4_l2_flags_buf_t { -#ifdef __AVX2__ - uint8_t pad[26]; /* 0, align th to 32 bytes */ -#else - uint8_t pad[2]; /* align iph to 4 bytes 0 */ -#endif - struct tap_hdr taph; /* 26 2 */ - struct iphdr iph; /* 44 20 */ - struct tcphdr th; /* 64 40 */ - char opts[OPT_MSS_LEN + OPT_WS_LEN + 1]; -#ifdef __AVX2__ -} __attribute__ ((packed, aligned(32))) -#else -} __attribute__ ((packed, aligned(__alignof__(unsigned int)))) -#endif -tcp4_l2_flags_buf[TCP_FRAMES_MEM]; - -static unsigned int tcp4_l2_flags_buf_used; - -/** - * tcp6_l2_flags_buf_t - IPv6 packet buffers for segments without data (flags) - * @pad: Align IPv6 header for checksum calculation to 32B (AVX2) or 4B - * @taph: Tap-level headers (partially pre-filled) - * @ip6h: Pre-filled IP header (except for payload_len and addresses) - * @th: Headroom for TCP header - * @opts: Headroom for TCP options - */ -static struct tcp6_l2_flags_buf_t { -#ifdef __AVX2__ - uint8_t pad[14]; /* 0 align ip6h to 32 bytes */ -#else - uint8_t pad[2]; /* align ip6h to 4 bytes 0 */ -#endif - struct tap_hdr taph; /* 14 2 */ - struct ipv6hdr ip6h; /* 32 20 */ - struct tcphdr th /* 72 */ __attribute__ ((aligned(4))); /* 60 */ - char opts[OPT_MSS_LEN + OPT_WS_LEN + 1]; -#ifdef __AVX2__ -} __attribute__ ((packed, aligned(32))) -#else -} __attribute__ ((packed, aligned(__alignof__(unsigned int)))) -#endif -tcp6_l2_flags_buf[TCP_FRAMES_MEM]; - -static unsigned int tcp6_l2_flags_buf_used; - #define CONN(idx) (&(FLOW(idx)->tcp)) /* Table for lookup from remote address, local port, remote port */ @@ -967,25 +916,14 @@ static void tcp_update_check_tcp6(struct ipv6hdr *ip6h, struct tcphdr *th) } /** - * tcp_update_l2_buf() - Update L2 buffers with Ethernet and IPv4 addresses + * tcp_update_l2_buf() - Update Ethernet header buffers with addresses * @eth_d: Ethernet destination address, NULL if unchanged * @eth_s: Ethernet source address, NULL if unchanged */ void tcp_update_l2_buf(const unsigned char *eth_d, const unsigned char *eth_s) { - int i; - - for (i = 0; i < TCP_FRAMES_MEM; i++) { - struct tcp4_l2_flags_buf_t *b4f = &tcp4_l2_flags_buf[i]; - struct tcp6_l2_flags_buf_t *b6f = &tcp6_l2_flags_buf[i]; - struct tcp4_l2_buf_t *b4 = &tcp4_l2_buf[i]; - struct tcp6_l2_buf_t *b6 = &tcp6_l2_buf[i]; - - eth_update_mac(&b4->taph.eh, eth_d, eth_s); - eth_update_mac(&b6->taph.eh, eth_d, eth_s); - eth_update_mac(&b4f->taph.eh, eth_d, eth_s); - eth_update_mac(&b6f->taph.eh, eth_d, eth_s); - } + eth_update_mac(&tcp4_eth_src, eth_d, eth_s); + eth_update_mac(&tcp6_eth_src, eth_d, eth_s); } /** @@ -998,26 +936,45 @@ static void tcp_sock4_iov_init(const struct ctx *c) struct iovec *iov; int i; - for (i = 0; i < ARRAY_SIZE(tcp4_l2_buf); i++) { - tcp4_l2_buf[i] = (struct tcp4_l2_buf_t) { - .taph = TAP_HDR_INIT(ETH_P_IP), - .iph = iph, - .th = { .doff = sizeof(struct tcphdr) / 4, .ack = 1 } - }; + tcp4_eth_src.h_proto = htons_constant(ETH_P_IP); + + for (i = 0; i < ARRAY_SIZE(tcp4_payload); i++) { + tcp4_payload_ip[i] = iph; + tcp4_payload[i].th.doff = sizeof(struct tcphdr) / 4; + tcp4_payload[i].th.ack = 1; } - for (i = 0; i < ARRAY_SIZE(tcp4_l2_flags_buf); i++) { - tcp4_l2_flags_buf[i] = (struct tcp4_l2_flags_buf_t) { - .taph = TAP_HDR_INIT(ETH_P_IP), - .iph = L2_BUF_IP4_INIT(IPPROTO_TCP) - }; + for (i = 0; i < ARRAY_SIZE(tcp4_flags); i++) { + tcp4_flags_ip[i] = iph; + tcp4_flags[i].th.doff = sizeof(struct tcphdr) / 4; + tcp4_flags[i].th.ack = 1; } - for (i = 0, iov = tcp4_l2_iov; i < TCP_FRAMES_MEM; i++, iov++) - iov->iov_base = tap_frame_base(c, &tcp4_l2_buf[i].taph); + for (i = 0; i < TCP_FRAMES_MEM; i++) { + iov = tcp4_l2_iov[i]; + + iov[TCP_IOV_VLEN].iov_base = &tcp4_payload_vnet_len[i]; + iov[TCP_IOV_VLEN].iov_len = c->mode == MODE_PASTA ? 0 : + sizeof(tcp4_payload_vnet_len[i]); + iov[TCP_IOV_ETH].iov_base = &tcp4_eth_src; + iov[TCP_IOV_ETH].iov_len = sizeof(tcp4_eth_src); + iov[TCP_IOV_IP].iov_base = &tcp4_payload_ip[i]; + iov[TCP_IOV_IP].iov_len = sizeof(tcp4_payload_ip[i]); + iov[TCP_IOV_PAYLOAD].iov_base = &tcp4_payload[i]; + } - for (i = 0, iov = tcp4_l2_flags_iov; i < TCP_FRAMES_MEM; i++, iov++) - iov->iov_base = tap_frame_base(c, &tcp4_l2_flags_buf[i].taph); + for (i = 0; i < TCP_FRAMES_MEM; i++) { + iov = tcp4_l2_flags_iov[i]; + + iov[TCP_IOV_VLEN].iov_base = &tcp4_flags_vnet_len[i]; + iov[TCP_IOV_VLEN].iov_len = c->mode == MODE_PASTA ? 0 : + sizeof(tcp4_flags_vnet_len[i]); + iov[TCP_IOV_ETH].iov_base = &tcp4_eth_src; + iov[TCP_IOV_ETH].iov_len = sizeof(tcp4_eth_src); + iov[TCP_IOV_IP].iov_base = &tcp4_flags_ip[i]; + iov[TCP_IOV_IP].iov_len = sizeof(tcp4_flags_ip[i]); + iov[TCP_IOV_PAYLOAD].iov_base = &tcp4_flags[i]; + } } /** @@ -1026,29 +983,49 @@ static void tcp_sock4_iov_init(const struct ctx *c) */ static void tcp_sock6_iov_init(const struct ctx *c) { + struct ipv6hdr ip6 = L2_BUF_IP6_INIT(IPPROTO_TCP); struct iovec *iov; int i; - for (i = 0; i < ARRAY_SIZE(tcp6_l2_buf); i++) { - tcp6_l2_buf[i] = (struct tcp6_l2_buf_t) { - .taph = TAP_HDR_INIT(ETH_P_IPV6), - .ip6h = L2_BUF_IP6_INIT(IPPROTO_TCP), - .th = { .doff = sizeof(struct tcphdr) / 4, .ack = 1 } - }; + tcp6_eth_src.h_proto = htons_constant(ETH_P_IPV6); + + for (i = 0; i < ARRAY_SIZE(tcp6_payload); i++) { + tcp6_payload_ip[i] = ip6; + tcp6_payload[i].th.doff = sizeof(struct tcphdr) / 4; + tcp6_payload[i].th.ack = 1; } - for (i = 0; i < ARRAY_SIZE(tcp6_l2_flags_buf); i++) { - tcp6_l2_flags_buf[i] = (struct tcp6_l2_flags_buf_t) { - .taph = TAP_HDR_INIT(ETH_P_IPV6), - .ip6h = L2_BUF_IP6_INIT(IPPROTO_TCP) - }; + for (i = 0; i < ARRAY_SIZE(tcp6_flags); i++) { + tcp6_flags_ip[i] = ip6; + tcp6_flags[i].th.doff = sizeof(struct tcphdr) / 4; + tcp6_flags[i].th .ack = 1; } - for (i = 0, iov = tcp6_l2_iov; i < TCP_FRAMES_MEM; i++, iov++) - iov->iov_base = tap_frame_base(c, &tcp6_l2_buf[i].taph); + for (i = 0; i < TCP_FRAMES_MEM; i++) { + iov = tcp6_l2_iov[i]; + + iov[TCP_IOV_VLEN].iov_base = &tcp6_payload_vnet_len[i]; + iov[TCP_IOV_VLEN].iov_len = c->mode == MODE_PASTA ? 0 : + sizeof(tcp6_payload_vnet_len[i]); + iov[TCP_IOV_ETH].iov_base = &tcp6_eth_src; + iov[TCP_IOV_ETH].iov_len = sizeof(tcp6_eth_src); + iov[TCP_IOV_IP].iov_base = &tcp6_payload_ip[i]; + iov[TCP_IOV_IP].iov_len = sizeof(tcp6_payload_ip[i]); + iov[TCP_IOV_PAYLOAD].iov_base = &tcp6_payload[i]; + } + + for (i = 0; i < TCP_FRAMES_MEM; i++) { + iov = tcp6_l2_flags_iov[i]; - for (i = 0, iov = tcp6_l2_flags_iov; i < TCP_FRAMES_MEM; i++, iov++) - iov->iov_base = tap_frame_base(c, &tcp6_l2_flags_buf[i].taph); + iov[TCP_IOV_VLEN].iov_base = &tcp6_flags_vnet_len[i]; + iov[TCP_IOV_VLEN].iov_len = c->mode == MODE_PASTA ? 0 : + sizeof(tcp6_flags_vnet_len[i]); + iov[TCP_IOV_ETH].iov_base = &tcp6_eth_src; + iov[TCP_IOV_ETH].iov_len = sizeof(tcp6_eth_src); + iov[TCP_IOV_IP].iov_base = &tcp6_flags_ip[i]; + iov[TCP_IOV_IP].iov_len = sizeof(tcp6_flags_ip[i]); + iov[TCP_IOV_PAYLOAD].iov_base = &tcp6_flags[i]; + } } /** @@ -1284,36 +1261,40 @@ static void tcp_rst_do(struct ctx *c, struct tcp_tap_conn *conn); } while (0) /** - * tcp_l2_flags_buf_flush() - Send out buffers for segments with no data (flags) + * tcp_flags_flush() - Send out buffers for segments with no data (flags) * @c: Execution context */ -static void tcp_l2_flags_buf_flush(const struct ctx *c) +static void tcp_flags_flush(const struct ctx *c) { - tap_send_frames(c, tcp6_l2_flags_iov, 1, tcp6_l2_flags_buf_used); - tcp6_l2_flags_buf_used = 0; + tap_send_frames(c, &tcp6_l2_flags_iov[0][0], TCP_NUM_IOVS, + tcp6_flags_used); + tcp6_flags_used = 0; - tap_send_frames(c, tcp4_l2_flags_iov, 1, tcp4_l2_flags_buf_used); - tcp4_l2_flags_buf_used = 0; + tap_send_frames(c, &tcp4_l2_flags_iov[0][0], TCP_NUM_IOVS, + tcp4_flags_used); + tcp4_flags_used = 0; } /** - * tcp_l2_data_buf_flush() - Send out buffers for segments with data + * tcp_payload_flush() - Send out buffers for segments with data * @c: Execution context */ -static void tcp_l2_data_buf_flush(const struct ctx *c) +static void tcp_payload_flush(const struct ctx *c) { unsigned i; size_t m; - m = tap_send_frames(c, tcp6_l2_iov, 1, tcp6_l2_buf_used); + m = tap_send_frames(c, &tcp6_l2_iov[0][0], TCP_NUM_IOVS, + tcp6_payload_used); for (i = 0; i < m; i++) - *tcp6_l2_buf_seq_update[i].seq += tcp6_l2_buf_seq_update[i].len; - tcp6_l2_buf_used = 0; + *tcp6_seq_update[i].seq += tcp6_seq_update[i].len; + tcp6_payload_used = 0; - m = tap_send_frames(c, tcp4_l2_iov, 1, tcp4_l2_buf_used); + m = tap_send_frames(c, &tcp4_l2_iov[0][0], TCP_NUM_IOVS, + tcp4_payload_used); for (i = 0; i < m; i++) - *tcp4_l2_buf_seq_update[i].seq += tcp4_l2_buf_seq_update[i].len; - tcp4_l2_buf_used = 0; + *tcp4_seq_update[i].seq += tcp4_seq_update[i].len; + tcp4_payload_used = 0; } /** @@ -1323,8 +1304,8 @@ static void tcp_l2_data_buf_flush(const struct ctx *c) /* cppcheck-suppress [constParameterPointer, unmatchedSuppression] */ void tcp_defer_handler(struct ctx *c) { - tcp_l2_flags_buf_flush(c); - tcp_l2_data_buf_flush(c); + tcp_flags_flush(c); + tcp_payload_flush(c); } /** @@ -1433,35 +1414,31 @@ static size_t tcp_fill_headers6(const struct ctx *c, * tcp_l2_buf_fill_headers() - Fill 802.3, IP, TCP headers in pre-cooked buffers * @c: Execution context * @conn: Connection pointer - * @p: Pointer to any type of TCP pre-cooked buffer + * @iov: Pointer to an array of iovec of TCP pre-cooked buffers * @plen: Payload length (including TCP header options) * @check: Checksum, if already known * @seq: Sequence number for this segment * - * Return: frame length including L2 headers, host order + * Return: IP payload length, host order */ static size_t tcp_l2_buf_fill_headers(const struct ctx *c, const struct tcp_tap_conn *conn, - void *p, size_t plen, + struct iovec *iov, size_t plen, const uint16_t *check, uint32_t seq) { const struct in_addr *a4 = inany_v4(&conn->faddr); size_t ip_len, tlen; if (a4) { - struct tcp4_l2_buf_t *b = (struct tcp4_l2_buf_t *)p; - - ip_len = tcp_fill_headers4(c, conn, &b->iph, &b->th, plen, + ip_len = tcp_fill_headers4(c, conn, iov[TCP_IOV_IP].iov_base, + iov[TCP_IOV_PAYLOAD].iov_base, plen, check, seq); - - tlen = tap_frame_len(c, &b->taph, ip_len); + tlen = ip_len - sizeof(struct iphdr); } else { - struct tcp6_l2_buf_t *b = (struct tcp6_l2_buf_t *)p; - - ip_len = tcp_fill_headers6(c, conn, &b->ip6h, &b->th, plen, + ip_len = tcp_fill_headers6(c, conn, iov[TCP_IOV_IP].iov_base, + iov[TCP_IOV_PAYLOAD].iov_base, plen, seq); - - tlen = tap_frame_len(c, &b->taph, ip_len); + tlen = ip_len - sizeof(struct ipv6hdr); } return tlen; @@ -1593,16 +1570,16 @@ static void tcp_update_seqack_from_tap(const struct ctx *c, */ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags) { - struct tcp4_l2_flags_buf_t *b4 = NULL; - struct tcp6_l2_flags_buf_t *b6 = NULL; + struct tcp_flags_t *payload; struct tcp_info tinfo = { 0 }; socklen_t sl = sizeof(tinfo); int s = conn->sock; + uint32_t vnet_len; size_t optlen = 0; - struct iovec *iov; struct tcphdr *th; + struct iovec *iov; + size_t ip_len; char *data; - void *p; if (SEQ_GE(conn->seq_ack_to_tap, conn->seq_from_tap) && !flags && conn->wnd_to_tap) @@ -1625,19 +1602,17 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags) return 0; if (CONN_V4(conn)) { - iov = tcp4_l2_flags_iov + tcp4_l2_flags_buf_used; - p = b4 = tcp4_l2_flags_buf + tcp4_l2_flags_buf_used++; - th = &b4->th; - - /* gcc 11.2 would complain on data = (char *)(th + 1); */ - data = b4->opts; + iov = tcp4_l2_flags_iov[tcp4_flags_used++]; + vnet_len = sizeof(struct ethhdr) + sizeof(struct iphdr); } else { - iov = tcp6_l2_flags_iov + tcp6_l2_flags_buf_used; - p = b6 = tcp6_l2_flags_buf + tcp6_l2_flags_buf_used++; - th = &b6->th; - data = b6->opts; + iov = tcp6_l2_flags_iov[tcp6_flags_used++]; + vnet_len = sizeof(struct ethhdr) + sizeof(struct ipv6hdr); } + payload = iov[TCP_IOV_PAYLOAD].iov_base; + th = &payload->th; + data = payload->opts; + if (flags & SYN) { int mss; @@ -1683,8 +1658,11 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags) th->syn = !!(flags & SYN); th->fin = !!(flags & FIN); - iov->iov_len = tcp_l2_buf_fill_headers(c, conn, p, optlen, - NULL, conn->seq_to_tap); + ip_len = tcp_l2_buf_fill_headers(c, conn, iov, optlen, NULL, + conn->seq_to_tap); + iov[TCP_IOV_PAYLOAD].iov_len = ip_len; + + *(uint32_t *)iov[TCP_IOV_VLEN].iov_base = htonl(vnet_len + ip_len); if (th->ack) { if (SEQ_GE(conn->seq_ack_to_tap, conn->seq_from_tap)) @@ -1700,24 +1678,27 @@ static int tcp_send_flag(struct ctx *c, struct tcp_tap_conn *conn, int flags) if (th->fin || th->syn) conn->seq_to_tap++; - if (CONN_V4(conn)) { - if (flags & DUP_ACK) { - memcpy(b4 + 1, b4, sizeof(*b4)); - (iov + 1)->iov_len = iov->iov_len; - tcp4_l2_flags_buf_used++; - } + if (flags & DUP_ACK) { + struct iovec *dup_iov; + int i; - if (tcp4_l2_flags_buf_used > ARRAY_SIZE(tcp4_l2_flags_buf) - 2) - tcp_l2_flags_buf_flush(c); - } else { - if (flags & DUP_ACK) { - memcpy(b6 + 1, b6, sizeof(*b6)); - (iov + 1)->iov_len = iov->iov_len; - tcp6_l2_flags_buf_used++; - } + if (CONN_V4(conn)) + dup_iov = tcp4_l2_flags_iov[tcp4_flags_used++]; + else + dup_iov = tcp6_l2_flags_iov[tcp6_flags_used++]; - if (tcp6_l2_flags_buf_used > ARRAY_SIZE(tcp6_l2_flags_buf) - 2) - tcp_l2_flags_buf_flush(c); + for (i = 0; i < TCP_NUM_IOVS; i++) + memcpy(dup_iov[i].iov_base, iov[i].iov_base, + iov[i].iov_len); + dup_iov[TCP_IOV_PAYLOAD].iov_len = iov[TCP_IOV_PAYLOAD].iov_len; + } + + if (CONN_V4(conn)) { + if (tcp4_flags_used > TCP_FRAMES_MEM - 2) + tcp_flags_flush(c); + } else { + if (tcp6_flags_used > TCP_FRAMES_MEM - 2) + tcp_flags_flush(c); } return 0; @@ -2164,30 +2145,42 @@ static void tcp_data_to_tap(const struct ctx *c, struct tcp_tap_conn *conn, { uint32_t *seq_update = &conn->seq_to_tap; struct iovec *iov; + size_t ip_len; + uint32_t vnet_len; if (CONN_V4(conn)) { - struct tcp4_l2_buf_t *b = &tcp4_l2_buf[tcp4_l2_buf_used]; - const uint16_t *check = no_csum ? &(b - 1)->iph.check : NULL; + struct iovec *iov_prev = tcp4_l2_iov[tcp4_payload_used - 1]; + const uint16_t *check = NULL; - tcp4_l2_buf_seq_update[tcp4_l2_buf_used].seq = seq_update; - tcp4_l2_buf_seq_update[tcp4_l2_buf_used].len = plen; + if (no_csum) { + struct iphdr *iph = iov_prev[TCP_IOV_IP].iov_base; + check = &iph->check; + } - iov = tcp4_l2_iov + tcp4_l2_buf_used++; - iov->iov_len = tcp_l2_buf_fill_headers(c, conn, b, plen, - check, seq); - if (tcp4_l2_buf_used > ARRAY_SIZE(tcp4_l2_buf) - 1) - tcp_l2_data_buf_flush(c); + tcp4_seq_update[tcp4_payload_used].seq = seq_update; + tcp4_seq_update[tcp4_payload_used].len = plen; + + iov = tcp4_l2_iov[tcp4_payload_used++]; + ip_len = tcp_l2_buf_fill_headers(c, conn, iov, plen, check, + seq); + iov[TCP_IOV_PAYLOAD].iov_len = ip_len; + vnet_len = sizeof(struct ethhdr) + sizeof(struct iphdr) + + ip_len; + *(uint32_t *)iov[TCP_IOV_VLEN].iov_base = htonl(vnet_len); + if (tcp4_payload_used > TCP_FRAMES_MEM - 1) + tcp_payload_flush(c); } else if (CONN_V6(conn)) { - struct tcp6_l2_buf_t *b = &tcp6_l2_buf[tcp6_l2_buf_used]; - - tcp6_l2_buf_seq_update[tcp6_l2_buf_used].seq = seq_update; - tcp6_l2_buf_seq_update[tcp6_l2_buf_used].len = plen; + tcp6_seq_update[tcp6_payload_used].seq = seq_update; + tcp6_seq_update[tcp6_payload_used].len = plen; - iov = tcp6_l2_iov + tcp6_l2_buf_used++; - iov->iov_len = tcp_l2_buf_fill_headers(c, conn, b, plen, - NULL, seq); - if (tcp6_l2_buf_used > ARRAY_SIZE(tcp6_l2_buf) - 1) - tcp_l2_data_buf_flush(c); + iov = tcp6_l2_iov[tcp6_payload_used++]; + ip_len = tcp_l2_buf_fill_headers(c, conn, iov, plen, NULL, seq); + iov[TCP_IOV_PAYLOAD].iov_len = ip_len; + vnet_len = sizeof(struct ethhdr) + sizeof(struct ipv6hdr) + + ip_len; + *(uint32_t *)iov[TCP_IOV_VLEN].iov_base = htonl(vnet_len); + if (tcp6_payload_used > TCP_FRAMES_MEM - 1) + tcp_payload_flush(c); } } @@ -2242,19 +2235,19 @@ static int tcp_data_from_sock(struct ctx *c, struct tcp_tap_conn *conn) iov_sock[0].iov_base = tcp_buf_discard; iov_sock[0].iov_len = already_sent; - if (( v4 && tcp4_l2_buf_used + fill_bufs > ARRAY_SIZE(tcp4_l2_buf)) || - (!v4 && tcp6_l2_buf_used + fill_bufs > ARRAY_SIZE(tcp6_l2_buf))) { - tcp_l2_data_buf_flush(c); + if (( v4 && tcp4_payload_used + fill_bufs > TCP_FRAMES_MEM) || + (!v4 && tcp6_payload_used + fill_bufs > TCP_FRAMES_MEM)) { + tcp_payload_flush(c); /* Silence Coverity CWE-125 false positive */ - tcp4_l2_buf_used = tcp6_l2_buf_used = 0; + tcp4_payload_used = tcp6_payload_used = 0; } for (i = 0, iov = iov_sock + 1; i < fill_bufs; i++, iov++) { if (v4) - iov->iov_base = &tcp4_l2_buf[tcp4_l2_buf_used + i].data; + iov->iov_base = &tcp4_payload[tcp4_payload_used + i].data; else - iov->iov_base = &tcp6_l2_buf[tcp6_l2_buf_used + i].data; + iov->iov_base = &tcp6_payload[tcp6_payload_used + i].data; iov->iov_len = mss; } if (iov_rem) @@ -2299,7 +2292,7 @@ static int tcp_data_from_sock(struct ctx *c, struct tcp_tap_conn *conn) plen = mss; seq = conn->seq_to_tap; for (i = 0; i < send_bufs; i++) { - int no_csum = i && i != send_bufs - 1 && tcp4_l2_buf_used; + int no_csum = i && i != send_bufs - 1 && tcp4_payload_used; if (i == send_bufs - 1) plen = last_len; @@ -32,6 +32,9 @@ #ifndef ETH_MIN_MTU #define ETH_MIN_MTU 68 #endif +#ifndef IP_MAX_MTU +#define IP_MAX_MTU USHRT_MAX +#endif #ifndef MIN #define MIN(x, y) (((x) < (y)) ? (x) : (y)) |