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Hallyn" , Eric Paris , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan , =?utf-8?q?Micka=C3=ABl_Sala=C3=BCn?= , =?utf-8?q?G=C3=BCnther_Noack?= Cc: linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, audit@vger.kernel.org, bpf@vger.kernel.org, linux-kselftest@vger.kernel.org, kernel-team@cloudflare.com, Frederick Lawler X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=22647; i=fred@cloudflare.com; h=from:subject:message-id; bh=B986+q0EPyEQDvxqJ//qZ7hW3q9zmixUG/Y18ImATFE=; b=owEBbQKS/ZANAwAKAasltHYDktNtAcsmYgBpsd8ox7VoA9tHygH6CdWnV5yXxCKCXYsthDZcm zaAQBG5hfWJAjMEAAEKAB0WIQTLNBqMVmu1PHvjOe2rJbR2A5LTbQUCabHfKAAKCRCrJbR2A5LT bSQ2D/4saIy2ZXQv1HF99uhbehkV7IRPcjBS9V9Xt+dosdvExoSYyqjUn0xk3ijXA4OZkfEYb5h 8Gre4xk+Q7VGn3Miht9uAiJJdNtJlZw7sJNJd1MyHXCv1Swb5wLxFOXG0QkabUYyu5G20ea6zYO KuJtTQLZN9YKJi/zWU/znZxwUNTHG6E4oLP0VbzdtL4WrSgMXNWzvYQXOIxF56M/SffERpRQkwa w+llPjdQRzpy6guEjAhpw4hy/m8rnD6d0d5T4oeL0kNMq6x0+WN3rzDNdkCWyYlrWaMHI9iE1IV WLMPk6cg5HYVhrb1F4DwDxgjWKQZAUr3hlZEikDOXuLGTjJ28pSsTWktfCYB5n1uCmfGJNZXAuA PTmJyXU+9L6ae/tNQXUByEIxNaJJMa8+BVZ5GETk7aS1Xy82ZWRySspyaiZ/wZ+SVbGjBowYVSE 68QhCrWrDjbgtgnaanRb4voF8KK25DqaOq/nJF5uXVciVLq7fMhlC6as5zvt0GtHj0offiJxKSL 4E/ncYWuKa4cbA1azHiyW+LmIM1x+G4RhsIbAVwfW9DB7TAzEM/2PzhEOTix2dtx68Sh0QMftge ufMiElHIbEbcXbfh3x3/XKXT/Lxu91HZZe4sOnrNnrZsjWSIG3Xl+IifdE+hEQjRWprzqtFc5Jv PBPmakjl+HSaGhw== X-Developer-Key: i=fred@cloudflare.com; a=openpgp; fpr=CB341A8C566BB53C7BE339EDAB25B4760392D36D Add selftests for the audit kfunc BPF LSM functionality including both the test program and BPF progs. Assisted-by: Claude:claude-4.5-opus Signed-off-by: Frederick Lawler --- .../selftests/bpf/prog_tests/lsm_audit_kfuncs.c | 598 +++++++++++++++++= ++++ .../selftests/bpf/progs/test_lsm_audit_kfuncs.c | 263 +++++++++ 2 files changed, 861 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/lsm_audit_kfuncs.c b/to= ols/testing/selftests/bpf/prog_tests/lsm_audit_kfuncs.c new file mode 100644 index 0000000000000000000000000000000000000000..de18e1a3c79578d4151a12a029f= 2a9e6cc7648e3 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/lsm_audit_kfuncs.c @@ -0,0 +1,598 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2026 Cloudflare */ +#define _GNU_SOURCE + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "audit_helpers.h" +#include "test_lsm_audit_kfuncs.skel.h" +#include "test_progs.h" + +#ifndef AUDIT_BPF_LSM_ACCESS +#define AUDIT_BPF_LSM_ACCESS 1427 +#endif + +static inline struct sockaddr_in addr4(void) +{ + return (struct sockaddr_in){ + .sin_family =3D AF_INET, + .sin_port =3D htons(1234), + .sin_addr.s_addr =3D htonl(INADDR_LOOPBACK), + }; +} + +static inline struct sockaddr_in6 addr6(void) +{ + return (struct sockaddr_in6){ + .sin6_family =3D AF_INET6, + .sin6_port =3D htons(1234), + .sin6_addr =3D in6addr_loopback, + }; +} + +static int bind_connect(const struct sockaddr *addr, int addrlen) +{ + int err; + int sock; + int opt =3D 1; + socklen_t optlen =3D sizeof(opt); + + sock =3D socket(addr->sa_family, SOCK_STREAM, 0); + if (!ASSERT_OK_FD(sock, "socket")) + return 1; + + err =3D setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &opt, optlen); + if (!ASSERT_OK(err, "setsockopt")) + goto done; + + err =3D bind(sock, addr, addrlen); + if (!ASSERT_OK(err, "bind")) + goto done; + + err =3D connect(sock, addr, addrlen); + ASSERT_OK(err, "connect"); + + err =3D getsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &opt, &optlen); + ASSERT_OK(err, "getsockopt"); + +done: + close(sock); + return err; +} + +static void test_audit_log_sockaddr_src(struct audit_observer *obs, + struct test_lsm_audit_kfuncs *skel) +{ + struct sockaddr_in sin =3D addr4(); + struct sockaddr_in6 sin6 =3D addr6(); + struct bpf_link *link; + + link =3D bpf_program__attach_lsm(skel->progs.test_sockaddr_src); + if (!ASSERT_OK_PTR(link, "attach")) + return; + + audit_observer_reset(obs); + + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, + "cause=3D\"bind4\" saddr=3D127.0.0.1 src=3D1234 netif=3Dlo", + 1); + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, + "cause=3D\"bind6\" saddr=3D::1 src=3D1234 netif=3Dlo", 1); + + if (bind_connect((const struct sockaddr *)&sin, sizeof(sin))) + goto done; + + if (bind_connect((const struct sockaddr *)&sin6, sizeof(sin6))) + goto done; + + ASSERT_OK(audit_observer_wait(obs), "audit_observer_wait"); + ASSERT_TRUE(audit_observer_check_satisfied(obs), + "all expectations met"); + +done: + bpf_link__destroy(link); +} + +static void test_audit_log_sockaddr_dest(struct audit_observer *obs, + struct test_lsm_audit_kfuncs *skel) +{ + struct sockaddr_in sin =3D addr4(); + struct sockaddr_in6 sin6 =3D addr6(); + struct bpf_link *link; + + link =3D bpf_program__attach_lsm(skel->progs.test_sockaddr_dest); + if (!ASSERT_OK_PTR(link, "attach")) + return; + + audit_observer_reset(obs); + + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, + "cause=3D\"connect4\" daddr=3D127.0.0.1 dest=3D1234 netif=3Dlo", + 1); + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, + "cause=3D\"connect6\" daddr=3D::1 dest=3D1234 netif=3Dlo", + 1); + + if (bind_connect((const struct sockaddr *)&sin, sizeof(sin))) + goto out; + + if (bind_connect((const struct sockaddr *)&sin6, sizeof(sin6))) + goto out; + + ASSERT_OK(audit_observer_wait(obs), "audit_observer_wait"); + ASSERT_TRUE(audit_observer_check_satisfied(obs), + "all expectations met"); + +out: + bpf_link__destroy(link); +} + +static void test_audit_log_sock(struct audit_observer *obs, + struct test_lsm_audit_kfuncs *skel) +{ + struct sockaddr_in sin =3D addr4(); + struct sockaddr_in6 sin6 =3D addr6(); + struct bpf_link *link; + + link =3D bpf_program__attach_lsm(skel->progs.test_sock); + if (!ASSERT_OK_PTR(link, "attach")) + return; + + audit_observer_reset(obs); + + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, + "cause=3D\"sock4\" laddr=3D127.0.0.1 lport=3D1234 faddr=3D127.0.0= .1 fport=3D1234 netif=3Dlo", + 1); + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, + "cause=3D\"sock6\" laddr=3D::1 lport=3D1234 faddr=3D::1 fport=3D1= 234 netif=3Dlo", + 1); + + if (bind_connect((const struct sockaddr *)&sin, sizeof(sin))) + goto out; + + if (bind_connect((const struct sockaddr *)&sin6, sizeof(sin6))) + goto out; + + ASSERT_OK(audit_observer_wait(obs), "audit_observer_wait"); + ASSERT_TRUE(audit_observer_check_satisfied(obs), + "all expectations met"); + +out: + bpf_link__destroy(link); +} + +static void test_audit_log_sock_unix(struct audit_observer *obs, + struct test_lsm_audit_kfuncs *skel) +{ + struct sockaddr_un addr; + struct bpf_link *link; + char expected[256]; + char sun_path[108]; + int server_fd =3D -1; + int opt =3D 1; + socklen_t optlen =3D sizeof(opt); + int err; + + snprintf(sun_path, sizeof(sun_path), "/root/tmp/bpf_audit_test_%d.sock", + getpid()); + + /* Ensure directory exists */ + mkdir("/root/tmp", 0755); + unlink(sun_path); + + link =3D bpf_program__attach_lsm(skel->progs.test_sock_unix); + if (!ASSERT_OK_PTR(link, "attach")) + return; + + audit_observer_reset(obs); + + snprintf(expected, sizeof(expected), "cause=3D\"sock_unix\" path=3D\"%s\"= ", + sun_path); + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, expected, 1); + + memset(&addr, 0, sizeof(addr)); + addr.sun_family =3D AF_UNIX; + strncpy(addr.sun_path, sun_path, sizeof(addr.sun_path) - 1); + + server_fd =3D socket(AF_UNIX, SOCK_STREAM, 0); + if (!ASSERT_OK_FD(server_fd, "socket")) + goto out; + + err =3D bind(server_fd, (struct sockaddr *)&addr, sizeof(addr)); + if (!ASSERT_OK(err, "bind")) + goto out; + + err =3D getsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR, &opt, &optlen); + ASSERT_OK(err, "getsockopt"); + + ASSERT_OK(audit_observer_wait(obs), "audit_observer_wait"); + ASSERT_TRUE(audit_observer_check_satisfied(obs), + "all expectations met"); + +out: + if (server_fd >=3D 0) + close(server_fd); + unlink(sun_path); + bpf_link__destroy(link); +} + +static void test_audit_log_file(struct audit_observer *obs, + struct test_lsm_audit_kfuncs *skel) +{ + struct bpf_link *link; + int err; + int fd; + + link =3D bpf_program__attach_lsm(skel->progs.test_file); + if (!ASSERT_OK_PTR(link, "attach")) + return; + + audit_observer_reset(obs); + + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, + "cause=3D\"file\" path=3D\"/dev/null\" dev=3D\"devtmpfs\" ino=3D4= ", + 1); + + fd =3D open("/dev/null", O_RDONLY); + close(fd); + if (!ASSERT_OK_FD(fd, "open(/dev/null)")) + goto out; + + err =3D audit_observer_wait(obs); + ASSERT_OK(err, "audit_observer_wait"); + ASSERT_TRUE(audit_observer_check_satisfied(obs), + "all expectations met"); + +out: + bpf_link__destroy(link); +} + +static void test_audit_log_path(struct audit_observer *obs, + struct test_lsm_audit_kfuncs *skel) +{ + struct bpf_link *link; + int err; + int fd; + + link =3D bpf_program__attach_lsm(skel->progs.test_file_path); + if (!ASSERT_OK_PTR(link, "attach")) + return; + + audit_observer_reset(obs); + + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, + "cause=3D\"path\" path=3D\"/dev/null\" dev=3D\"devtmpfs\" ino=3D4= ", + 1); + + fd =3D open("/dev/null", O_RDONLY); + close(fd); + if (!ASSERT_OK_FD(fd, "open(/dev/null)")) + goto out; + + err =3D audit_observer_wait(obs); + ASSERT_OK(err, "audit_observer_wait"); + ASSERT_TRUE(audit_observer_check_satisfied(obs), + "all expectations met"); + +out: + bpf_link__destroy(link); +} + +static void test_audit_log_dentry(struct audit_observer *obs, + struct test_lsm_audit_kfuncs *skel) +{ + struct bpf_link *link; + char expected[128]; + char buf[64]; + int err; + + link =3D bpf_program__attach_lsm(skel->progs.test_dentry); + if (!ASSERT_OK_PTR(link, "attach")) + return; + + audit_observer_reset(obs); + + snprintf(expected, sizeof(expected), + "cause=3D\"dentry\" name=3D\"exe\" dev=3D"); + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, expected, 1); + + /* readlink triggers inode_readlink hook */ + err =3D readlink("/proc/self/exe", buf, sizeof(buf)); + if (!ASSERT_GT(err, 0, "readlink(/proc/self/exe)")) + goto out; + + err =3D audit_observer_wait(obs); + ASSERT_OK(err, "audit_observer_wait"); + ASSERT_TRUE(audit_observer_check_satisfied(obs), + "all expectations met"); + +out: + bpf_link__destroy(link); +} + +static void test_audit_log_inode(struct audit_observer *obs, + struct test_lsm_audit_kfuncs *skel) +{ + struct bpf_link *link; + char expected[128]; + struct stat st; + int err; + int fd; + + if (!ASSERT_OK(stat("/dev/null", &st), "stat(/dev/null)")) + return; + + link =3D bpf_program__attach_lsm(skel->progs.test_inode); + if (!ASSERT_OK_PTR(link, "attach")) + return; + + audit_observer_reset(obs); + + snprintf(expected, sizeof(expected), + "cause=3D\"inode\" name=3D\"null\" dev=3D\"devtmpfs\" ino=3D%lu", + st.st_ino); + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, expected, 1); + + fd =3D open("/dev/null", O_RDONLY); + close(fd); + if (!ASSERT_OK_FD(fd, "open(/dev/null)")) + goto out; + + err =3D audit_observer_wait(obs); + ASSERT_OK(err, "audit_observer_wait"); + ASSERT_TRUE(audit_observer_check_satisfied(obs), + "all expectations met"); + +out: + bpf_link__destroy(link); +} + +static void test_audit_log_task(struct audit_observer *obs, + struct test_lsm_audit_kfuncs *skel) +{ + struct bpf_link *link; + char expected[128]; + pid_t pid; + int err; + + pid =3D getpid(); + + link =3D bpf_program__attach_lsm(skel->progs.test_task); + if (!ASSERT_OK_PTR(link, "attach")) + return; + + audit_observer_reset(obs); + + snprintf(expected, sizeof(expected), + "cause=3D\"task\" opid=3D%d ocomm=3D\"test_progs\"", pid); + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, expected, 1); + + err =3D getpgid(pid); + if (!ASSERT_GT(err, -1, "pid pgid match")) + goto out; + + err =3D audit_observer_wait(obs); + ASSERT_OK(err, "audit_observer_wait"); + ASSERT_TRUE(audit_observer_check_satisfied(obs), + "all expectations met"); + +out: + bpf_link__destroy(link); +} + +static void test_audit_log_cap(struct audit_observer *obs, + struct test_lsm_audit_kfuncs *skel) +{ + struct bpf_link *link; + int err; + int fd; + + link =3D bpf_program__attach_lsm(skel->progs.test_cap); + if (!ASSERT_OK_PTR(link, "attach")) + return; + + audit_observer_reset(obs); + + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, + "cause=3D\"cap\" capability=3D", 1); + + fd =3D open("/proc/kallsyms", O_RDONLY); + close(fd); + if (!ASSERT_OK_FD(fd, "open(/proc/kallsyms)")) + goto out; + + err =3D audit_observer_wait(obs); + ASSERT_OK(err, "audit_observer_wait"); + ASSERT_TRUE(audit_observer_check_satisfied(obs), + "all expectations met"); + +out: + bpf_link__destroy(link); +} + +static void test_audit_log_ioctl_op(struct audit_observer *obs, + struct test_lsm_audit_kfuncs *skel) +{ + struct bpf_link *link; + char expected[128]; + struct stat st; + int err; + int fd; + + if (!ASSERT_OK(stat("/dev/null", &st), "stat(/dev/null)")) + return; + + link =3D bpf_program__attach_lsm(skel->progs.test_ioctl_op); + if (!ASSERT_OK_PTR(link, "attach")) + return; + + audit_observer_reset(obs); + + snprintf(expected, sizeof(expected), + "cause=3D\"ioctl_op\" path=3D\"/dev/null\" dev=3D\"devtmpfs\" ino=3D%lu= ioctlcmd=3D0x%x", + st.st_ino, TCGETS); + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, expected, 1); + + fd =3D open("/dev/null", O_RDONLY); + if (!ASSERT_OK_FD(fd, "open(/dev/null)")) + goto out; + + /* ioctl will fail with ENOTTY but the LSM hook fires regardless */ + ioctl(fd, TCGETS, NULL); + close(fd); + + err =3D audit_observer_wait(obs); + ASSERT_OK(err, "audit_observer_wait"); + ASSERT_TRUE(audit_observer_check_satisfied(obs), + "all expectations met"); + +out: + bpf_link__destroy(link); +} + +static void test_audit_log_sleepable(struct audit_observer *obs, + struct test_lsm_audit_kfuncs *skel) +{ + struct bpf_link *link; + int err; + int fd; + + link =3D bpf_program__attach_lsm(skel->progs.test_sleepable); + if (!ASSERT_OK_PTR(link, "attach")) + return; + + audit_observer_reset(obs); + + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, + "cause=3D\"sleepable\" path=3D\"/dev/null\" dev=3D\"devtmpfs\" in= o=3D4", + 1); + + fd =3D open("/dev/null", O_RDONLY); + close(fd); + if (!ASSERT_OK_FD(fd, "open(/dev/null)")) + goto out; + + err =3D audit_observer_wait(obs); + ASSERT_OK(err, "audit_observer_wait"); + ASSERT_TRUE(audit_observer_check_satisfied(obs), + "all expectations met"); + +out: + bpf_link__destroy(link); +} + +static void +test_audit_log_sockaddr_both_null(struct audit_observer *obs, + struct test_lsm_audit_kfuncs *skel) +{ + struct sockaddr_in sin =3D addr4(); + struct bpf_link *link; + + link =3D bpf_program__attach_lsm(skel->progs.test_sockaddr_both_null); + if (!ASSERT_OK_PTR(link, "attach")) + return; + + audit_observer_reset(obs); + + /* Should see cause but no saddr/daddr since both were NULL */ + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, + "cause=3D\"sockaddr_both_null\"", 1); + + bind_connect((const struct sockaddr *)&sin, sizeof(sin)); + + ASSERT_OK(audit_observer_wait(obs), "audit_observer_wait"); + ASSERT_TRUE(audit_observer_check_satisfied(obs), + "all expectations met"); + + bpf_link__destroy(link); +} + +static void +test_audit_log_sockaddr_small_addrlen(struct audit_observer *obs, + struct test_lsm_audit_kfuncs *skel) +{ + struct sockaddr_in sin =3D addr4(); + struct bpf_link *link; + + link =3D bpf_program__attach_lsm(skel->progs.test_sockaddr_small_addrlen); + if (!ASSERT_OK_PTR(link, "attach")) + return; + + audit_observer_reset(obs); + + /* Should see cause but no saddr since addrlen was too small */ + audit_observer_expect(obs, AUDIT_BPF_LSM_ACCESS, + "cause=3D\"sockaddr_small_addrlen\"", 1); + + bind_connect((const struct sockaddr *)&sin, sizeof(sin)); + + ASSERT_OK(audit_observer_wait(obs), "audit_observer_wait"); + ASSERT_TRUE(audit_observer_check_satisfied(obs), + "all expectations met"); + + bpf_link__destroy(link); +} + +void test_lsm_audit_kfuncs(void) +{ + struct test_lsm_audit_kfuncs *skel =3D NULL; + struct audit_observer obs; + FILE *log =3D NULL; + int audit_fd; + + audit_fd =3D audit_init(); + if (!ASSERT_GE(audit_fd, 0, "audit_init")) + return; + + if (env.verbosity > VERBOSE_NONE) + log =3D env.stdout_saved; + + audit_observer_init(&obs, audit_fd, log, 500); + + skel =3D test_lsm_audit_kfuncs__open_and_load(); + if (!ASSERT_OK_PTR(skel, "skel load")) + goto close_prog; + + if (test__start_subtest("net")) { + test_audit_log_sockaddr_src(&obs, skel); + test_audit_log_sockaddr_dest(&obs, skel); + test_audit_log_sockaddr_both_null(&obs, skel); + test_audit_log_sockaddr_small_addrlen(&obs, skel); + test_audit_log_sock(&obs, skel); + test_audit_log_sock_unix(&obs, skel); + } + + if (test__start_subtest("file")) { + test_audit_log_file(&obs, skel); + test_audit_log_path(&obs, skel); + test_audit_log_dentry(&obs, skel); + test_audit_log_inode(&obs, skel); + } + + if (test__start_subtest("task")) { + test_audit_log_task(&obs, skel); + test_audit_log_cap(&obs, skel); + } + + if (test__start_subtest("ioctl")) + test_audit_log_ioctl_op(&obs, skel); + + if (test__start_subtest("sleepable")) + test_audit_log_sleepable(&obs, skel); + +close_prog: + test_lsm_audit_kfuncs__destroy(skel); + audit_cleanup(audit_fd); +} diff --git a/tools/testing/selftests/bpf/progs/test_lsm_audit_kfuncs.c b/to= ols/testing/selftests/bpf/progs/test_lsm_audit_kfuncs.c new file mode 100644 index 0000000000000000000000000000000000000000..952ba09fce638f3bd14c18060a5= baa3ccaec19ca --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_lsm_audit_kfuncs.c @@ -0,0 +1,263 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2026 Cloudflare */ + +#include +#include +#include +#include +#include + +#define AF_UNIX 1 +#define AF_INET 2 +#define AF_INET6 10 + +char _license[] SEC("license") =3D "GPL"; + +SEC("lsm/socket_bind") +int BPF_PROG(test_sockaddr_src, struct socket *sock, struct sockaddr *addr= ess, + int addrlen) +{ + struct bpf_audit_context *ac; + + ac =3D bpf_audit_log_start(); + if (!ac) + return -ENOMEM; + + switch (address->sa_family) { + case AF_INET: + bpf_audit_log_cause(ac, "bind4"); + break; + case AF_INET6: + bpf_audit_log_cause(ac, "bind6"); + } + + bpf_audit_log_net_sockaddr(ac, 1, address, NULL, addrlen); + bpf_audit_log_end(ac); + return 0; +} + +SEC("lsm/socket_connect") +int BPF_PROG(test_sockaddr_dest, struct socket *sock, struct sockaddr *add= ress, + int addrlen) +{ + struct bpf_audit_context *ac; + + ac =3D bpf_audit_log_start(); + if (!ac) + return -ENOMEM; + + switch (address->sa_family) { + case AF_INET: + bpf_audit_log_cause(ac, "connect4"); + break; + case AF_INET6: + bpf_audit_log_cause(ac, "connect6"); + } + + bpf_audit_log_net_sockaddr(ac, 1, NULL, address, addrlen); + bpf_audit_log_end(ac); + return 0; +} + +SEC("lsm/socket_bind") +int BPF_PROG(test_sockaddr_both_null, struct socket *sock, + struct sockaddr *address, int addrlen) +{ + struct bpf_audit_context *ac; + + ac =3D bpf_audit_log_start(); + if (!ac) + return -ENOMEM; + + bpf_audit_log_cause(ac, "sockaddr_both_null"); + bpf_audit_log_net_sockaddr(ac, 1, NULL, NULL, addrlen); + bpf_audit_log_end(ac); + return 0; +} + +SEC("lsm/socket_bind") +int BPF_PROG(test_sockaddr_small_addrlen, struct socket *sock, + struct sockaddr *address, int addrlen) +{ + struct bpf_audit_context *ac; + + if (address->sa_family !=3D AF_INET) + return -EINVAL; + + ac =3D bpf_audit_log_start(); + if (!ac) + return -ENOMEM; + + bpf_audit_log_cause(ac, "sockaddr_small_addrlen"); + bpf_audit_log_net_sockaddr(ac, 1, address, NULL, 1); + bpf_audit_log_end(ac); + return 0; +} + +SEC("lsm/socket_getsockopt") +int BPF_PROG(test_sock, struct socket *sock, int level, int optname) +{ + struct bpf_audit_context *ac; + struct sock *sk =3D sock->sk; + + if (!sk) + return -EINVAL; + + ac =3D bpf_audit_log_start(); + if (!ac) + return -ENOMEM; + + switch (sk->__sk_common.skc_family) { + case AF_INET: + bpf_audit_log_cause(ac, "sock4"); + break; + case AF_INET6: + bpf_audit_log_cause(ac, "sock6"); + } + + bpf_audit_log_net_sock(ac, 1, sock); + bpf_audit_log_end(ac); + return 0; +} + +SEC("lsm/socket_getsockopt") +int BPF_PROG(test_sock_unix, struct socket *sock, int level, int optname) +{ + struct bpf_audit_context *ac; + struct sock *sk =3D sock->sk; + + if (!sk || sk->__sk_common.skc_family !=3D AF_UNIX) + return -EINVAL; + + ac =3D bpf_audit_log_start(); + if (!ac) + return -ENOMEM; + + bpf_audit_log_cause(ac, "sock_unix"); + bpf_audit_log_net_sock(ac, 0, sock); + bpf_audit_log_end(ac); + return 0; +} + +SEC("lsm/file_open") +int BPF_PROG(test_file, struct file *file) +{ + struct bpf_audit_context *ac; + + ac =3D bpf_audit_log_start(); + if (!ac) + return -ENOMEM; + + bpf_audit_log_cause(ac, "file"); + bpf_audit_log_file(ac, file); + bpf_audit_log_end(ac); + return 0; +} + +SEC("lsm/file_open") +int BPF_PROG(test_file_path, struct file *file) +{ + struct bpf_audit_context *ac; + + ac =3D bpf_audit_log_start(); + if (!ac) + return -ENOMEM; + + bpf_audit_log_cause(ac, "path"); + bpf_audit_log_path(ac, &file->f_path); + bpf_audit_log_end(ac); + return 0; +} + +SEC("lsm/inode_readlink") +int BPF_PROG(test_dentry, struct dentry *dentry) +{ + struct bpf_audit_context *ac; + + ac =3D bpf_audit_log_start(); + if (!ac) + return -ENOMEM; + + bpf_audit_log_cause(ac, "dentry"); + bpf_audit_log_dentry(ac, dentry); + bpf_audit_log_end(ac); + return 0; +} + +SEC("lsm/file_open") +int BPF_PROG(test_inode, struct file *file) +{ + struct bpf_audit_context *ac; + + ac =3D bpf_audit_log_start(); + if (!ac) + return -ENOMEM; + + bpf_audit_log_cause(ac, "inode"); + bpf_audit_log_inode(ac, file->f_inode); + bpf_audit_log_end(ac); + return 0; +} + +SEC("lsm/task_getpgid") +int BPF_PROG(test_task, struct task_struct *task) +{ + struct bpf_audit_context *ac; + + ac =3D bpf_audit_log_start(); + if (!ac) + return -ENOMEM; + + bpf_audit_log_cause(ac, "task"); + bpf_audit_log_task(ac, task); + bpf_audit_log_end(ac); + return 0; +} + +SEC("lsm/capable") +int BPF_PROG(test_cap, const struct cred *cred, struct user_namespace *ns, + int cap, unsigned int opts) +{ + struct bpf_audit_context *ac; + + ac =3D bpf_audit_log_start(); + if (!ac) + return -ENOMEM; + + bpf_audit_log_cause(ac, "cap"); + bpf_audit_log_cap(ac, cap); + bpf_audit_log_end(ac); + return 0; +} + +SEC("lsm/file_ioctl") +int BPF_PROG(test_ioctl_op, struct file *file, unsigned int cmd, + unsigned long arg) +{ + struct bpf_audit_context *ac; + + ac =3D bpf_audit_log_start(); + if (!ac) + return -ENOMEM; + + bpf_audit_log_cause(ac, "ioctl_op"); + bpf_audit_log_ioctl_op(ac, file, cmd); + bpf_audit_log_end(ac); + return 0; +} + +SEC("lsm.s/file_open") +int BPF_PROG(test_sleepable, struct file *file) +{ + struct bpf_audit_context *ac; + + ac =3D bpf_audit_log_start(); + if (!ac) + return -ENOMEM; + + bpf_audit_log_cause(ac, "sleepable"); + bpf_audit_log_file(ac, file); + bpf_audit_log_end(ac); + return 0; +} + --=20 2.43.0