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
---
tcp.c | 43 +++++++++++++------------------------------
1 file changed, 13 insertions(+), 30 deletions(-)
diff --git a/tcp.c b/tcp.c
index b9d0510..59e03ff 100644
--- a/tcp.c
+++ b/tcp.c
@@ -1999,17 +1999,11 @@ static void tcp_clamp_window(const struct ctx *c, struct tcp_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_conn *conn,
+ const struct timespec *now)
{
struct {
struct in6_addr src;
@@ -2017,19 +2011,17 @@ static uint32_t tcp_seq_init(const struct ctx *c, int af, const void *addr,
struct in6_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;
- if (af == AF_INET) {
- struct in6_addr tmp;
- encode_ip4mapped_ip6(&tmp, addr);
- in.src = tmp;
- encode_ip4mapped_ip6(&tmp, &c->ip4.addr);
- in.dst = tmp;
+ if (CONN_V4(conn)) {
+ struct in6_addr v4mapped;
+ encode_ip4mapped_ip6(&v4mapped, &c->ip4.addr);
+ in.dst = v4mapped;
} else {
- in.src = *(struct in6_addr *)addr;
in.dst = c->ip6.addr;
}
@@ -2038,7 +2030,7 @@ 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;
}
/**
@@ -2199,7 +2191,7 @@ 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);
@@ -2855,11 +2847,6 @@ static void tcp_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;
@@ -2874,13 +2861,9 @@ static void tcp_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;
--
2.38.1