Hello Jon,
On Sat, Aug 24, 2024 at 5:19 AM <jmaloy@xxxxxxxxxx> wrote:
>
> From: Jon Maloy <jmaloy@xxxxxxxxxx>
>
> We add a selftest to check that the new feature added in
> commit 05ea491641d3 ("tcp: add support for SO_PEEK_OFF socket option")
> works correctly.
>
> Reviewed-by: Stefano Brivio <sbrivio@xxxxxxxxxx>
> Tested-by: Stefano Brivio <sbrivio@xxxxxxxxxx>
> Signed-off-by: Jon Maloy <jmaloy@xxxxxxxxxx>
Thanks for working on this. Sorry that I just noticed I missed your
previous reply :(
> ---
> tools/testing/selftests/net/Makefile | 1 +
> tools/testing/selftests/net/tcp_so_peek_off.c | 181 ++++++++++++++++++
> 2 files changed, 182 insertions(+)
> create mode 100644 tools/testing/selftests/net/tcp_so_peek_off.c
>
> diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
> index 8eaffd7a641c..1179e3261bef 100644
> --- a/tools/testing/selftests/net/Makefile
> +++ b/tools/testing/selftests/net/Makefile
> @@ -80,6 +80,7 @@ TEST_PROGS += io_uring_zerocopy_tx.sh
> TEST_GEN_FILES += bind_bhash
> TEST_GEN_PROGS += sk_bind_sendto_listen
> TEST_GEN_PROGS += sk_connect_zero_addr
> +TEST_GEN_PROGS += tcp_so_peek_off
> TEST_PROGS += test_ingress_egress_chaining.sh
> TEST_GEN_PROGS += so_incoming_cpu
> TEST_PROGS += sctp_vrf.sh
> diff --git a/tools/testing/selftests/net/tcp_so_peek_off.c b/tools/testing/selftests/net/tcp_so_peek_off.c
> new file mode 100644
> index 000000000000..8379ea02e3d7
> --- /dev/null
> +++ b/tools/testing/selftests/net/tcp_so_peek_off.c
> @@ -0,0 +1,181 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <unistd.h>
> +#include <errno.h>
> +#include <sys/types.h>
> +#include <netinet/in.h>
> +#include <arpa/inet.h>
> +#include "../kselftest.h"
> +
> +static char *afstr(int af)
> +{
> + return af == AF_INET ? "TCP/IPv4" : "TCP/IPv6";
> +}
> +
> +int tcp_peek_offset_probe(sa_family_t af)
> +{
> + int optv = 0;
> + int ret = 0;
> + int s;
> +
> + s = socket(af, SOCK_STREAM | SOCK_CLOEXEC, IPPROTO_TCP);
> + if (s < 0) {
> + ksft_perror("Temporary TCP socket creation failed");
> + } else {
> + if (!setsockopt(s, SOL_SOCKET, SO_PEEK_OFF, &optv, sizeof(int)))
> + ret = 1;
> + else
> + printf("%s does not support SO_PEEK_OFF\n", afstr(af));
> + close(s);
> + }
> + return ret;
> +}
> +
> +static void tcp_peek_offset_set(int s, int offset)
> +{
> + if (setsockopt(s, SOL_SOCKET, SO_PEEK_OFF, &offset, sizeof(offset)))
> + ksft_perror("Failed to set SO_PEEK_OFF value\n");
> +}
> +
> +static int tcp_peek_offset_get(int s)
> +{
> + int offset;
> + socklen_t len = sizeof(offset);
> +
> + if (getsockopt(s, SOL_SOCKET, SO_PEEK_OFF, &offset, &len))
> + ksft_perror("Failed to get SO_PEEK_OFF value\n");
> + return offset;
> +}
> +
> +static int tcp_peek_offset_test(sa_family_t af)
> +{
> + union {
> + struct sockaddr sa;
> + struct sockaddr_in a4;
> + struct sockaddr_in6 a6;
> + } a;
> + int res = 0;
> + int s[2] = {0, 0};
> + int recv_sock = 0;
> + int offset = 0;
> + ssize_t len;
> + char buf;
> +
> + memset(&a, 0, sizeof(a));
> + a.sa.sa_family = af;
> +
> + s[0] = socket(af, SOCK_STREAM, IPPROTO_TCP);
> + s[1] = socket(af, SOCK_STREAM | SOCK_NONBLOCK, IPPROTO_TCP);
> +
> + if (s[0] < 0 || s[1] < 0) {
> + ksft_perror("Temporary probe socket creation failed\n");
> + goto out;
Nit: I wonder if we can use more proper test statements to avoid such
hiding failure[1] when closing a invalid file descriptor, even though
it doesn't harm the test itself?
[1]: "EBADF (Bad file descriptor)"
> + }
> + if (bind(s[0], &a.sa, sizeof(a)) < 0) {
> + ksft_perror("Temporary probe socket bind() failed\n");
> + goto out;
> + }
> + if (getsockname(s[0], &a.sa, &((socklen_t) { sizeof(a) })) < 0) {
> + ksft_perror("Temporary probe socket getsockname() failed\n");
> + goto out;
> + }
> + if (listen(s[0], 0) < 0) {
> + ksft_perror("Temporary probe socket listen() failed\n");
> + goto out;
> + }
> + if (connect(s[1], &a.sa, sizeof(a)) >= 0 || errno != EINPROGRESS) {
> + ksft_perror("Temporary probe socket connect() failed\n");
> + goto out;
> + }
> + recv_sock = accept(s[0], NULL, NULL);
> + if (recv_sock <= 0) {
> + ksft_perror("Temporary probe socket accept() failed\n");
> + goto out;
Same here.
> + }
> +
> + /* Some basic tests of getting/setting offset */
> + offset = tcp_peek_offset_get(recv_sock);
> + if (offset != -1) {
> + ksft_perror("Initial value of socket offset not -1\n");
> + goto out;
> + }
> + tcp_peek_offset_set(recv_sock, 0);
> + offset = tcp_peek_offset_get(recv_sock);
> + if (offset != 0) {
> + ksft_perror("Failed to set socket offset to 0\n");
> + goto out;
> + }
> +
> + /* Transfer a message */
> + if (send(s[1], (char *)("ab"), 2, 0) <= 0 || errno != EINPROGRESS) {
> + ksft_perror("Temporary probe socket send() failed\n");
> + goto out;
> + }
> + /* Read first byte */
> + len = recv(recv_sock, &buf, 1, MSG_PEEK);
> + if (len != 1 || buf != 'a') {
> + ksft_perror("Failed to read first byte of message\n");
> + goto out;
> + }
> + offset = tcp_peek_offset_get(recv_sock);
> + if (offset != 1) {
> + ksft_perror("Offset not forwarded correctly at first byte\n");
> + goto out;
> + }
> + /* Try to read beyond last byte */
> + len = recv(recv_sock, &buf, 2, MSG_PEEK);
> + if (len != 1 || buf != 'b') {
> + ksft_perror("Failed to read last byte of message\n");
> + goto out;
> + }
> + offset = tcp_peek_offset_get(recv_sock);
> + if (offset != 2) {
> + ksft_perror("Offset not forwarded correctly at last byte\n");
> + goto out;
> + }
> + /* Flush message */
> + len = recv(recv_sock, NULL, 2, MSG_TRUNC);
> + if (len != 2) {
> + ksft_perror("Failed to flush message\n");
> + goto out;
> + }
> + offset = tcp_peek_offset_get(recv_sock);
> + if (offset != 0) {
> + ksft_perror("Offset not reverted correctly after flush\n");
> + goto out;
> + }
> +
> + printf("%s with MSG_PEEK_OFF works correctly\n", afstr(af));
> + res = 1;
> +out:
> + close(recv_sock);
> + close(s[1]);
> + close(s[0]);
> + return res;
> +}
> +
> +int main(void)
> +{
> + int res4, res6;
> +
> + res4 = tcp_peek_offset_probe(AF_INET);
> + res6 = tcp_peek_offset_probe(AF_INET6);
> +
> + if (!res4 && !res6)
> + return KSFT_SKIP;
> +
> + if (res4)
> + res4 = tcp_peek_offset_test(AF_INET);
> +
> + if (res6)
> + res6 = tcp_peek_offset_test(AF_INET6);
> +
> + if (!res4 || !res6)
What if res6 is NULL after checking tcp_peek_offset_probe() while res4
is always working correctly, then we will get notified with a
KSFT_FAIL failure instead of KSFT_SKIP.
The thing could happen because you reuse the same return value for v4/v6 mode.
Thanks,
Jason
> + return KSFT_FAIL;
> +
> + return KSFT_PASS;
> +}
> +
> --
> 2.45.2
>
>
