tests: net: pmtu: Add IPv4 specific PMTU TCP tests

Allow tests to check whether a IPv4 TCP connection MTU is changed.

Signed-off-by: Jukka Rissanen <jukka.rissanen@nordicsemi.no>
This commit is contained in:
Jukka Rissanen 2024-11-05 18:10:00 +02:00 committed by Anas Nashif
commit 55e582635f
2 changed files with 139 additions and 0 deletions

View file

@ -4494,6 +4494,20 @@ static void testing_find_conn(struct tcp *conn, void *user_data)
data->mtu = net_tcp_get_supported_mss(conn) + NET_IPV6TCPH_LEN; data->mtu = net_tcp_get_supported_mss(conn) + NET_IPV6TCPH_LEN;
return; return;
} }
if (IS_ENABLED(CONFIG_NET_IPV4) && data->remote.sa_family == AF_INET &&
net_ipv4_addr_cmp(&conn->dst.sin.sin_addr,
&net_sin(&data->remote)->sin_addr)) {
if (data->mtu > 0) {
/* Set it only once */
return;
}
NET_DBG("Found connection %p mtu %u", conn,
net_tcp_get_supported_mss(conn) + NET_IPV4TCPH_LEN);
data->mtu = net_tcp_get_supported_mss(conn) + NET_IPV4TCPH_LEN;
return;
}
} }
uint16_t net_tcp_get_mtu(struct sockaddr *dst) uint16_t net_tcp_get_mtu(struct sockaddr *dst)

View file

@ -35,7 +35,9 @@ LOG_MODULE_REGISTER(net_test, CONFIG_NET_PMTU_LOG_LEVEL);
#include "route.h" #include "route.h"
#include "icmpv6.h" #include "icmpv6.h"
#include "icmpv4.h"
#include "ipv6.h" #include "ipv6.h"
#include "ipv4.h"
#include "pmtu.h" #include "pmtu.h"
#define NET_LOG_ENABLED 1 #define NET_LOG_ENABLED 1
@ -514,4 +516,127 @@ ZTEST(net_pmtu_test_suite, test_pmtu_05_ipv6_tcp)
#endif /* CONFIG_NET_IPV6_PMTU */ #endif /* CONFIG_NET_IPV6_PMTU */
} }
#if defined(CONFIG_NET_IPV4_PMTU)
static int get_v4_send_recv_sock(int *srv_sock,
struct sockaddr_in *my_saddr,
struct sockaddr_in *peer_saddr)
{
struct sockaddr addr;
socklen_t addrlen = sizeof(addr);
int new_sock;
int c_sock;
int s_sock;
prepare_sock_tcp_v4(PEER_IPV4_ADDR, PEER_PORT, &s_sock, peer_saddr);
test_bind(s_sock, (struct sockaddr *)peer_saddr, sizeof(*peer_saddr));
test_listen(s_sock);
prepare_sock_tcp_v4(MY_IPV4_ADDR, MY_PORT, &c_sock, my_saddr);
test_bind(c_sock, (struct sockaddr *)my_saddr, sizeof(*my_saddr));
test_connect(c_sock, (struct sockaddr *)peer_saddr, sizeof(*peer_saddr));
test_accept(s_sock, &new_sock, &addr, &addrlen);
zassert_equal(addrlen, sizeof(struct sockaddr_in), "wrong addrlen");
*srv_sock = new_sock;
return c_sock;
}
static int create_icmpv4_dest_unreach(struct net_if *iface,
struct sockaddr_in *src,
struct sockaddr_in *dst,
uint32_t mtu,
struct net_pkt **pkt)
{
struct net_icmpv4_dest_unreach du_hdr;
struct net_pkt *du_pkt;
struct in_addr *dest4;
struct in_addr *src4;
int ret;
du_pkt = net_pkt_alloc_with_buffer(iface, sizeof(struct net_ipv4_hdr) +
sizeof(struct net_icmp_hdr) +
sizeof(struct net_icmpv4_dest_unreach),
AF_INET, IPPROTO_ICMP,
PKT_WAIT_TIME);
if (du_pkt == NULL) {
NET_DBG("No buffer");
return -ENOMEM;
}
dest4 = &dst->sin_addr;
src4 = &src->sin_addr;
ret = net_ipv4_create(du_pkt, src4, dest4);
if (ret < 0) {
LOG_ERR("Cannot create IPv4 pkt (%d)", ret);
return ret;
}
ret = net_icmpv4_create(du_pkt, NET_ICMPV4_DST_UNREACH, 0);
if (ret < 0) {
LOG_ERR("Cannot create ICMPv4 pkt (%d)", ret);
return ret;
}
du_hdr.mtu = htons(mtu);
ret = net_pkt_write(du_pkt, &du_hdr, sizeof(du_hdr));
if (ret < 0) {
LOG_ERR("Cannot write payload (%d)", ret);
return ret;
}
net_pkt_cursor_init(du_pkt);
net_ipv4_finalize(du_pkt, IPPROTO_ICMP);
net_pkt_set_iface(du_pkt, iface);
*pkt = du_pkt;
return 0;
}
#endif
ZTEST(net_pmtu_test_suite, test_pmtu_05_ipv4_tcp)
{
#if defined(CONFIG_NET_IPV4_PMTU)
struct sockaddr_in dest_ipv4;
struct sockaddr_in s_saddr = { 0 }; /* peer */
struct sockaddr_in c_saddr = { 0 }; /* this host */
struct net_pkt *pkt = NULL;
int client_sock, server_sock;
uint16_t mtu;
int ret;
dest_ipv4.sin_family = AF_INET;
client_sock = get_v4_send_recv_sock(&server_sock, &c_saddr, &s_saddr);
zassert_true(client_sock >= 0, "Failed to create client socket");
/* Set initial MTU for the destination */
ret = net_pmtu_update_mtu((struct sockaddr *)&c_saddr, 4096);
zassert_true(ret >= 0, "PMTU IPv6 MTU update failed (%d)", ret);
/* Send an ICMPv4 "Destination Unreachable" message from server to client which
* will update the PMTU entry.
*/
ret = create_icmpv4_dest_unreach(target_iface, &s_saddr, &c_saddr, 2048, &pkt);
zassert_equal(ret, 0, "Failed to create ICMPv4 Destination Unrechable message");
ret = net_send_data(pkt);
zassert_equal(ret, 0, "Failed to send Destination Unreachable message");
/* Check that the PMTU entry has been updated */
mtu = net_tcp_get_mtu((struct sockaddr *)&s_saddr);
zassert_equal(mtu, 2048, "PMTU IPv4 MTU is not correct (%d)", mtu);
(void)zsock_close(client_sock);
(void)zsock_close(server_sock);
#else
ztest_test_skip();
#endif /* CONFIG_NET_IPV4_PMTU */
}
ZTEST_SUITE(net_pmtu_test_suite, NULL, test_setup, NULL, NULL, NULL); ZTEST_SUITE(net_pmtu_test_suite, NULL, test_setup, NULL, NULL, NULL);