diff options
| -rw-r--r-- | tcp.c | 33 |
1 files changed, 11 insertions, 22 deletions
@@ -970,26 +970,27 @@ static int tcp_is_dupack(int s, uint32_t ack_seq) } /** - * tcp_sock_consume() - Consume (discard) data from socket buffer + * tcp_sock_consume() - Consume (discard) data from buffer, update ACK sequence * @s: File descriptor number for socket * @ack_seq: ACK sequence, host order - * - * Return: negative on invalid sequence, 0 otherwise */ -static int tcp_sock_consume(int s, uint32_t ack_seq) +static void tcp_sock_consume(int s, uint32_t ack_seq) { int to_ack; /* Implicitly take care of wrap-arounds */ to_ack = ack_seq - tc[s].seq_ack_from_tap; + /* Simply ignore out-of-order ACKs: we already consumed the data we + * needed from the buffer, and we won't rewind back to a lower ACK + * sequence. + */ if (to_ack < 0) - return -EIO; + return; recv(s, NULL, to_ack, MSG_DONTWAIT | MSG_TRUNC); - tc[s].seq_ack_from_tap = ack_seq; - return 0; + tc[s].seq_ack_from_tap = ack_seq; } /** @@ -1146,12 +1147,7 @@ void tcp_tap_handler(struct ctx *c, int af, void *addr, char *in, size_t len) if (len == off) retrans = tcp_is_dupack(s, ntohl(th->ack_seq)); - if (tcp_sock_consume(s, ntohl(th->ack_seq))) { - tcp_rst(c, s); - return; - } - - tc[s].seq_ack_from_tap = ntohl(th->ack_seq); + tcp_sock_consume(s, ntohl(th->ack_seq)); if (retrans) tc[s].seq_to_tap = tc[s].seq_ack_from_tap; @@ -1177,10 +1173,7 @@ void tcp_tap_handler(struct ctx *c, int af, void *addr, char *in, size_t len) break; case CLOSE_WAIT: - if (tcp_sock_consume(s, ntohl(th->ack_seq))) { - tcp_rst(c, s); - return; - } + tcp_sock_consume(s, ntohl(th->ack_seq)); if (skip < len - off && tcp_send_to_sock(c, s, in + off + skip, len - off - skip, @@ -1282,11 +1275,7 @@ void tcp_sock_handler(struct ctx *c, int s, uint32_t events) shutdown(s, SHUT_RD); tcp_data_from_sock(c, s); tcp_send_to_tap(c, s, FIN | ACK, NULL, 0); - - if (tcp_sock_consume(s, tc[s].seq_ack_from_tap)) { - tcp_rst(c, s); - return; - } + tcp_sock_consume(s, tc[s].seq_ack_from_tap); } } } |