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// SPDX-License-Identifier: GPL-2.0
#include <test_progs.h>
#include "cgroup_helpers.h"
#include <linux/tcp.h>
#include "sockopt_sk.skel.h"
#ifndef SOL_TCP
#define SOL_TCP IPPROTO_TCP
#endif
#define SOL_CUSTOM 0xdeadbeef
static int getsetsockopt(void)
{
int fd, err;
union {
char u8[4];
__u32 u32;
char cc[16]; /* TCP_CA_NAME_MAX */
struct tcp_zerocopy_receive zc;
} buf = {};
socklen_t optlen;
char *big_buf = NULL;
fd = socket(AF_INET, SOCK_STREAM, 0);
if (fd < 0) {
log_err("Failed to create socket");
return -1;
}
/* IP_TOS - BPF bypass */
optlen = getpagesize() * 2;
big_buf = calloc(1, optlen);
if (!big_buf) {
log_err("Couldn't allocate two pages");
goto err;
}
*(int *)big_buf = 0x08;
err = setsockopt(fd, SOL_IP, IP_TOS, big_buf, optlen);
if (err) {
log_err("Failed to call setsockopt(IP_TOS)");
goto err;
}
memset(big_buf, 0, optlen);
optlen = 1;
err = getsockopt(fd, SOL_IP, IP_TOS, big_buf, &optlen);
if (err) {
log_err("Failed to call getsockopt(IP_TOS)");
goto err;
}
if (*big_buf != 0x08) {
log_err("Unexpected getsockopt(IP_TOS) optval 0x%x != 0x08",
(int)*big_buf);
goto err;
}
/* IP_TTL - EPERM */
buf.u8[0] = 1;
err = setsockopt(fd, SOL_IP, IP_TTL, &buf, 1);
if (!err || errno != EPERM) {
log_err("Unexpected success from setsockopt(IP_TTL)");
goto err;
}
/* SOL_CUSTOM - handled by BPF */
buf.u8[0] = 0x01;
err = setsockopt(fd, SOL_CUSTOM, 0, &buf, 1);
if (err) {
log_err("Failed to call setsockopt");
goto err;
}
buf.u32 = 0x00;
optlen = 4;
err = getsockopt(fd, SOL_CUSTOM, 0, &buf, &optlen);
if (err) {
log_err("Failed to call getsockopt");
goto err;
}
if (optlen != 1) {
log_err("Unexpected optlen %d != 1", optlen);
goto err;
}
if (buf.u8[0] != 0x01) {
log_err("Unexpected buf[0] 0x%02x != 0x01", buf.u8[0]);
goto err;
}
/* IP_FREEBIND - BPF can't access optval past PAGE_SIZE */
optlen = getpagesize() * 2;
memset(big_buf, 0, optlen);
err = setsockopt(fd, SOL_IP, IP_FREEBIND, big_buf, optlen);
if (err != 0) {
log_err("Failed to call setsockopt, ret=%d", err);
goto err;
}
err = getsockopt(fd, SOL_IP, IP_FREEBIND, big_buf, &optlen);
if (err != 0) {
log_err("Failed to call getsockopt, ret=%d", err);
goto err;
}
if (optlen != 1 || *(__u8 *)big_buf != 0x55) {
log_err("Unexpected IP_FREEBIND getsockopt, optlen=%d, optval=0x%x",
optlen, *(__u8 *)big_buf);
}
/* SO_SNDBUF is overwritten */
buf.u32 = 0x01010101;
err = setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &buf, 4);
if (err) {
log_err("Failed to call setsockopt(SO_SNDBUF)");
goto err;
}
buf.u32 = 0x00;
optlen = 4;
err = getsockopt(fd, SOL_SOCKET, SO_SNDBUF, &buf, &optlen);
if (err) {
log_err("Failed to call getsockopt(SO_SNDBUF)");
goto err;
}
if (buf.u32 != 0x55AA*2) {
log_err("Unexpected getsockopt(SO_SNDBUF) 0x%x != 0x55AA*2",
buf.u32);
goto err;
}
/* TCP_CONGESTION can extend the string */
strcpy(buf.cc, "nv");
err = setsockopt(fd, SOL_TCP, TCP_CONGESTION, &buf, strlen("nv"));
if (err) {
log_err("Failed to call setsockopt(TCP_CONGESTION)");
goto err;
}
optlen = sizeof(buf.cc);
err = getsockopt(fd, SOL_TCP, TCP_CONGESTION, &buf, &optlen);
if (err) {
log_err("Failed to call getsockopt(TCP_CONGESTION)");
goto err;
}
if (strcmp(buf.cc, "cubic") != 0) {
log_err("Unexpected getsockopt(TCP_CONGESTION) %s != %s",
buf.cc, "cubic");
goto err;
}
/* TCP_ZEROCOPY_RECEIVE triggers */
memset(&buf, 0, sizeof(buf));
optlen = sizeof(buf.zc);
err = getsockopt(fd, SOL_TCP, TCP_ZEROCOPY_RECEIVE, &buf, &optlen);
if (err) {
log_err("Unexpected getsockopt(TCP_ZEROCOPY_RECEIVE) err=%d errno=%d",
err, errno);
goto err;
}
memset(&buf, 0, sizeof(buf));
buf.zc.address = 12345; /* rejected by BPF */
optlen = sizeof(buf.zc);
errno = 0;
err = getsockopt(fd, SOL_TCP, TCP_ZEROCOPY_RECEIVE, &buf, &optlen);
if (errno != EPERM) {
log_err("Unexpected getsockopt(TCP_ZEROCOPY_RECEIVE) err=%d errno=%d",
err, errno);
goto err;
}
free(big_buf);
close(fd);
return 0;
err:
free(big_buf);
close(fd);
return -1;
}
static void run_test(int cgroup_fd)
{
struct sockopt_sk *skel;
skel = sockopt_sk__open_and_load();
if (!ASSERT_OK_PTR(skel, "skel_load"))
goto cleanup;
skel->bss->page_size = getpagesize();
skel->links._setsockopt =
bpf_program__attach_cgroup(skel->progs._setsockopt, cgroup_fd);
if (!ASSERT_OK_PTR(skel->links._setsockopt, "setsockopt_link"))
goto cleanup;
skel->links._getsockopt =
bpf_program__attach_cgroup(skel->progs._getsockopt, cgroup_fd);
if (!ASSERT_OK_PTR(skel->links._getsockopt, "getsockopt_link"))
goto cleanup;
ASSERT_OK(getsetsockopt(), "getsetsockopt");
cleanup:
sockopt_sk__destroy(skel);
}
void test_sockopt_sk(void)
{
int cgroup_fd;
cgroup_fd = test__join_cgroup("/sockopt_sk");
if (CHECK_FAIL(cgroup_fd < 0))
return;
run_test(cgroup_fd);
close(cgroup_fd);
}
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