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 <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
This commit is contained in:
David Gibson 2022-11-17 16:59:00 +11:00 committed by Stefano Brivio
parent a93bfada5b
commit e7bae5bafd

34
tcp.c
View file

@ -1930,16 +1930,10 @@ 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,
static void tcp_seq_init(const struct ctx *c, struct tcp_tap_conn *conn,
const struct timespec *now)
{
union inany_addr aany;
@ -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;