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// SPDX-License-Identifier: GPL-2.0
#include <test_progs.h>
#include "bind_perm.skel.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/capability.h>
static int duration;
void try_bind(int family, int port, int expected_errno)
{
struct sockaddr_storage addr = {};
struct sockaddr_in6 *sin6;
struct sockaddr_in *sin;
int fd = -1;
fd = socket(family, SOCK_STREAM, 0);
if (CHECK(fd < 0, "fd", "errno %d", errno))
goto close_socket;
if (family == AF_INET) {
sin = (struct sockaddr_in *)&addr;
sin->sin_family = family;
sin->sin_port = htons(port);
} else {
sin6 = (struct sockaddr_in6 *)&addr;
sin6->sin6_family = family;
sin6->sin6_port = htons(port);
}
errno = 0;
bind(fd, (struct sockaddr *)&addr, sizeof(addr));
ASSERT_EQ(errno, expected_errno, "bind");
close_socket:
if (fd >= 0)
close(fd);
}
bool cap_net_bind_service(cap_flag_value_t flag)
{
const cap_value_t cap_net_bind_service = CAP_NET_BIND_SERVICE;
cap_flag_value_t original_value;
bool was_effective = false;
cap_t caps;
caps = cap_get_proc();
if (CHECK(!caps, "cap_get_proc", "errno %d", errno))
goto free_caps;
if (CHECK(cap_get_flag(caps, CAP_NET_BIND_SERVICE, CAP_EFFECTIVE,
&original_value),
"cap_get_flag", "errno %d", errno))
goto free_caps;
was_effective = (original_value == CAP_SET);
if (CHECK(cap_set_flag(caps, CAP_EFFECTIVE, 1, &cap_net_bind_service,
flag),
"cap_set_flag", "errno %d", errno))
goto free_caps;
if (CHECK(cap_set_proc(caps), "cap_set_proc", "errno %d", errno))
goto free_caps;
free_caps:
CHECK(cap_free(caps), "cap_free", "errno %d", errno);
return was_effective;
}
void test_bind_perm(void)
{
bool cap_was_effective;
struct bind_perm *skel;
int cgroup_fd;
cgroup_fd = test__join_cgroup("/bind_perm");
if (CHECK(cgroup_fd < 0, "cg-join", "errno %d", errno))
return;
skel = bind_perm__open_and_load();
if (!ASSERT_OK_PTR(skel, "skel"))
goto close_cgroup_fd;
skel->links.bind_v4_prog = bpf_program__attach_cgroup(skel->progs.bind_v4_prog, cgroup_fd);
if (!ASSERT_OK_PTR(skel, "bind_v4_prog"))
goto close_skeleton;
skel->links.bind_v6_prog = bpf_program__attach_cgroup(skel->progs.bind_v6_prog, cgroup_fd);
if (!ASSERT_OK_PTR(skel, "bind_v6_prog"))
goto close_skeleton;
cap_was_effective = cap_net_bind_service(CAP_CLEAR);
try_bind(AF_INET, 110, EACCES);
try_bind(AF_INET6, 110, EACCES);
try_bind(AF_INET, 111, 0);
try_bind(AF_INET6, 111, 0);
if (cap_was_effective)
cap_net_bind_service(CAP_SET);
close_skeleton:
bind_perm__destroy(skel);
close_cgroup_fd:
close(cgroup_fd);
}
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