From e7bae5bafdd1c8c061c6c319488b48a4e2536236 Mon Sep 17 00:00:00 2001 From: David Gibson Date: Thu, 17 Nov 2022 16:59:00 +1100 Subject: [PATCH] tcp: Have tcp_seq_init() take its parameters from struct tcp_conn tcp_seq_init() takes a number of parameters for the connection, but at every call site, these are already populated in the tcp_conn structure. Likewise we always store the result into the @seq_to_tap field. Use this to simplify tcp_seq_init(). Signed-off-by: David Gibson Signed-off-by: Stefano Brivio --- tcp.c | 36 ++++++++++-------------------------- 1 file changed, 10 insertions(+), 26 deletions(-) diff --git a/tcp.c b/tcp.c index ac64b81..dabcbc4 100644 --- a/tcp.c +++ b/tcp.c @@ -1930,17 +1930,11 @@ static void tcp_clamp_window(const struct ctx *c, struct tcp_tap_conn *conn, /** * tcp_seq_init() - Calculate initial sequence number according to RFC 6528 * @c: Execution context - * @af: Address family, AF_INET or AF_INET6 - * @addr: Remote address, pointer to in_addr or in6_addr - * @dstport: Destination port, connection-wise, network order - * @srcport: Source port, connection-wise, network order + * @conn: TCP connection, with addr, sock_port and tap_port populated * @now: Current timestamp - * - * Return: initial TCP sequence */ -static uint32_t tcp_seq_init(const struct ctx *c, int af, const void *addr, - in_port_t dstport, in_port_t srcport, - const struct timespec *now) +static void tcp_seq_init(const struct ctx *c, struct tcp_tap_conn *conn, + const struct timespec *now) { union inany_addr aany; struct { @@ -1949,14 +1943,13 @@ static uint32_t tcp_seq_init(const struct ctx *c, int af, const void *addr, union inany_addr dst; in_port_t dstport; } __attribute__((__packed__)) in = { - .srcport = srcport, - .dstport = dstport, + .src = conn->addr, + .srcport = conn->tap_port, + .dstport = conn->sock_port, }; uint32_t ns, seq = 0; - inany_from_af(&aany, af, addr); - in.src = aany; - if (af == AF_INET) + if (CONN_V4(conn)) inany_from_af(&aany, AF_INET, &c->ip4.addr); else inany_from_af(&aany, AF_INET6, &c->ip6.addr); @@ -1967,7 +1960,7 @@ static uint32_t tcp_seq_init(const struct ctx *c, int af, const void *addr, ns = now->tv_sec * 1E9; ns += now->tv_nsec >> 5; /* 32ns ticks, overflows 32 bits every 137s */ - return seq + ns; + conn->seq_to_tap = seq + ns; } /** @@ -2127,7 +2120,7 @@ static void tcp_conn_from_tap(struct ctx *c, int af, const void *addr, conn->seq_from_tap = conn->seq_init_from_tap + 1; conn->seq_ack_to_tap = conn->seq_from_tap; - conn->seq_to_tap = tcp_seq_init(c, af, addr, th->dest, th->source, now); + tcp_seq_init(c, conn, now); conn->seq_ack_from_tap = conn->seq_to_tap + 1; tcp_hash_insert(c, conn); @@ -2774,11 +2767,6 @@ static void tcp_tap_conn_from_sock(struct ctx *c, union epoll_ref ref, conn->sock_port = ntohs(sa6.sin6_port); conn->tap_port = ref.r.p.tcp.tcp.index; - - conn->seq_to_tap = tcp_seq_init(c, AF_INET6, &sa6.sin6_addr, - conn->sock_port, - conn->tap_port, - now); } else { struct sockaddr_in sa4; @@ -2793,13 +2781,9 @@ static void tcp_tap_conn_from_sock(struct ctx *c, union epoll_ref ref, conn->sock_port = ntohs(sa4.sin_port); conn->tap_port = ref.r.p.tcp.tcp.index; - - conn->seq_to_tap = tcp_seq_init(c, AF_INET, &sa4.sin_addr, - conn->sock_port, - conn->tap_port, - now); } + tcp_seq_init(c, conn, now); tcp_hash_insert(c, conn); conn->seq_ack_from_tap = conn->seq_to_tap + 1;