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 <david(a)gibson.dropbear.id.au>
---
tcp.c | 36 ++++++++++--------------------------
1 file changed, 10 insertions(+), 26 deletions(-)
diff --git a/tcp.c b/tcp.c
index d4e9838..7156246 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;
--
2.38.1