| Message ID | 20240904104824.1844082-16-ivanov.mikhail1@huawei-partners.com (mailing list archive) |
|---|---|
| State | RFC |
| Headers | show |
| Series | Support socket access-control | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch, async |
On Wed, Sep 04, 2024 at 06:48:20PM +0800, Mikhail Ivanov wrote: > It is possible to branch off an SCTP UDP association into a separate > user space UDP socket. Add test validating that such scenario is not > restricted by Landlock. > > Move setup_loopback() helper from net_test to common.h to use it to > enable connection in this test. > > Signed-off-by: Mikhail Ivanov <ivanov.mikhail1@huawei-partners.com> > --- > tools/testing/selftests/landlock/common.h | 12 +++ > tools/testing/selftests/landlock/net_test.c | 11 -- > .../testing/selftests/landlock/socket_test.c | 102 +++++++++++++++++- > 3 files changed, 113 insertions(+), 12 deletions(-) > > diff --git a/tools/testing/selftests/landlock/common.h b/tools/testing/selftests/landlock/common.h > index 28df49fa22d5..07d959a8ac7b 100644 > --- a/tools/testing/selftests/landlock/common.h > +++ b/tools/testing/selftests/landlock/common.h > @@ -16,6 +16,7 @@ > #include <sys/types.h> > #include <sys/wait.h> > #include <unistd.h> > +#include <sched.h> > > #include "../kselftest_harness.h" > > @@ -227,3 +228,14 @@ enforce_ruleset(struct __test_metadata *const _metadata, const int ruleset_fd) > TH_LOG("Failed to enforce ruleset: %s", strerror(errno)); > } > } > + > +static void setup_loopback(struct __test_metadata *const _metadata) > +{ > + set_cap(_metadata, CAP_SYS_ADMIN); > + ASSERT_EQ(0, unshare(CLONE_NEWNET)); > + clear_cap(_metadata, CAP_SYS_ADMIN); > + > + set_ambient_cap(_metadata, CAP_NET_ADMIN); > + ASSERT_EQ(0, system("ip link set dev lo up")); > + clear_ambient_cap(_metadata, CAP_NET_ADMIN); > +} > diff --git a/tools/testing/selftests/landlock/net_test.c b/tools/testing/selftests/landlock/net_test.c > index f21cfbbc3638..0b8386657c72 100644 > --- a/tools/testing/selftests/landlock/net_test.c > +++ b/tools/testing/selftests/landlock/net_test.c > @@ -103,17 +103,6 @@ static int set_service(struct service_fixture *const srv, > return 1; > } > > -static void setup_loopback(struct __test_metadata *const _metadata) > -{ > - set_cap(_metadata, CAP_SYS_ADMIN); > - ASSERT_EQ(0, unshare(CLONE_NEWNET)); > - clear_cap(_metadata, CAP_SYS_ADMIN); > - > - set_ambient_cap(_metadata, CAP_NET_ADMIN); > - ASSERT_EQ(0, system("ip link set dev lo up")); > - clear_ambient_cap(_metadata, CAP_NET_ADMIN); > -} > - > static bool is_restricted(const struct protocol_variant *const prot, > const enum sandbox_type sandbox) > { > diff --git a/tools/testing/selftests/landlock/socket_test.c b/tools/testing/selftests/landlock/socket_test.c > index 67db0e1c1121..2ab27196fa3d 100644 > --- a/tools/testing/selftests/landlock/socket_test.c > +++ b/tools/testing/selftests/landlock/socket_test.c > @@ -11,8 +11,11 @@ > #include <linux/pfkeyv2.h> > #include <linux/kcm.h> > #include <linux/can.h> > -#include <linux/in.h> > +#include <sys/socket.h> > +#include <stdint.h> > +#include <linux/sctp.h> > #include <sys/prctl.h> > +#include <arpa/inet.h> > > #include "common.h" > > @@ -839,4 +842,101 @@ TEST_F(socket_creation, socketpair) > } > } > > +static const char loopback_ipv4[] = "127.0.0.1"; > +static const int backlog = 10; > +static const int loopback_port = 1024; > + > +TEST_F(socket_creation, sctp_peeloff) > +{ > + int status, ret; > + pid_t child; > + struct sockaddr_in addr; > + int server_fd; > + > + server_fd = > + socket(AF_INET, SOCK_SEQPACKET | SOCK_CLOEXEC, IPPROTO_SCTP); > + ASSERT_LE(0, server_fd); > + > + addr.sin_family = AF_INET; > + addr.sin_port = htons(loopback_port); > + addr.sin_addr.s_addr = inet_addr(loopback_ipv4); > + > + ASSERT_EQ(0, bind(server_fd, &addr, sizeof(addr))); > + ASSERT_EQ(0, listen(server_fd, backlog)); > + > + child = fork(); > + ASSERT_LE(0, child); > + if (child == 0) { > + int client_fd; > + sctp_peeloff_flags_arg_t peeloff; > + socklen_t peeloff_size = sizeof(peeloff); > + const struct landlock_ruleset_attr ruleset_attr = { > + .handled_access_socket = LANDLOCK_ACCESS_SOCKET_CREATE, > + }; > + struct landlock_socket_attr sctp_socket_create = { > + .allowed_access = LANDLOCK_ACCESS_SOCKET_CREATE, > + .family = AF_INET, > + .type = SOCK_SEQPACKET, > + }; > + > + /* Closes listening socket for the child. */ > + ASSERT_EQ(0, close(server_fd)); > + > + client_fd = socket(AF_INET, SOCK_SEQPACKET | SOCK_CLOEXEC, > + IPPROTO_SCTP); > + ASSERT_LE(0, client_fd); > + > + /* > + * Establishes connection between sockets and > + * gets SCTP association id. > + */ > + ret = setsockopt(client_fd, IPPROTO_SCTP, SCTP_SOCKOPT_CONNECTX, > + &addr, sizeof(addr)); > + ASSERT_LE(0, ret); > + > + if (self->sandboxed) { > + /* Denies creation of SCTP sockets. */ > + int ruleset_fd = landlock_create_ruleset( > + &ruleset_attr, sizeof(ruleset_attr), 0); > + ASSERT_LE(0, ruleset_fd); > + > + if (self->allowed) { > + ASSERT_EQ(0, landlock_add_rule( > + ruleset_fd, > + LANDLOCK_RULE_SOCKET, > + &sctp_socket_create, 0)); > + } > + enforce_ruleset(_metadata, ruleset_fd); > + ASSERT_EQ(0, close(ruleset_fd)); > + } > + /* > + * Branches off current SCTP association into a separate socket > + * and returns it to user space. > + */ > + peeloff.p_arg.associd = ret; > + ret = getsockopt(client_fd, IPPROTO_SCTP, SCTP_SOCKOPT_PEELOFF, > + &peeloff, &peeloff_size); > + > + /* > + * Creation of SCTP socket by branching off existing SCTP association > + * should not be restricted by Landlock. > + */ > + EXPECT_LE(0, ret); > + > + /* Closes peeloff socket if such was created. */ > + if (!ret) { > + ASSERT_EQ(0, close(peeloff.p_arg.sd)); > + } Nit: Should this check for (ret >= 0) instead? I imagine that getsockopt returns -1 on error, normally, and that would make it past the EXPECT_LE (even if it logs a failure). > + ASSERT_EQ(0, close(client_fd)); > + _exit(_metadata->exit_code); > + return; > + } > + > + ASSERT_EQ(child, waitpid(child, &status, 0)); > + ASSERT_EQ(1, WIFEXITED(status)); > + ASSERT_EQ(EXIT_SUCCESS, WEXITSTATUS(status)); > + > + ASSERT_EQ(0, close(server_fd)); > +} > + > TEST_HARNESS_MAIN > -- > 2.34.1 > Reviewed-by: Günther Noack <gnoack@google.com>
On 9/27/2024 5:35 PM, Günther Noack wrote: > On Wed, Sep 04, 2024 at 06:48:20PM +0800, Mikhail Ivanov wrote: >> It is possible to branch off an SCTP UDP association into a separate >> user space UDP socket. Add test validating that such scenario is not >> restricted by Landlock. >> >> Move setup_loopback() helper from net_test to common.h to use it to >> enable connection in this test. >> >> Signed-off-by: Mikhail Ivanov <ivanov.mikhail1@huawei-partners.com> >> --- >> tools/testing/selftests/landlock/common.h | 12 +++ >> tools/testing/selftests/landlock/net_test.c | 11 -- >> .../testing/selftests/landlock/socket_test.c | 102 +++++++++++++++++- >> 3 files changed, 113 insertions(+), 12 deletions(-) >> >> diff --git a/tools/testing/selftests/landlock/common.h b/tools/testing/selftests/landlock/common.h >> index 28df49fa22d5..07d959a8ac7b 100644 >> --- a/tools/testing/selftests/landlock/common.h >> +++ b/tools/testing/selftests/landlock/common.h >> @@ -16,6 +16,7 @@ >> #include <sys/types.h> >> #include <sys/wait.h> >> #include <unistd.h> >> +#include <sched.h> >> >> #include "../kselftest_harness.h" >> >> @@ -227,3 +228,14 @@ enforce_ruleset(struct __test_metadata *const _metadata, const int ruleset_fd) >> TH_LOG("Failed to enforce ruleset: %s", strerror(errno)); >> } >> } >> + >> +static void setup_loopback(struct __test_metadata *const _metadata) >> +{ >> + set_cap(_metadata, CAP_SYS_ADMIN); >> + ASSERT_EQ(0, unshare(CLONE_NEWNET)); >> + clear_cap(_metadata, CAP_SYS_ADMIN); >> + >> + set_ambient_cap(_metadata, CAP_NET_ADMIN); >> + ASSERT_EQ(0, system("ip link set dev lo up")); >> + clear_ambient_cap(_metadata, CAP_NET_ADMIN); >> +} >> diff --git a/tools/testing/selftests/landlock/net_test.c b/tools/testing/selftests/landlock/net_test.c >> index f21cfbbc3638..0b8386657c72 100644 >> --- a/tools/testing/selftests/landlock/net_test.c >> +++ b/tools/testing/selftests/landlock/net_test.c >> @@ -103,17 +103,6 @@ static int set_service(struct service_fixture *const srv, >> return 1; >> } >> >> -static void setup_loopback(struct __test_metadata *const _metadata) >> -{ >> - set_cap(_metadata, CAP_SYS_ADMIN); >> - ASSERT_EQ(0, unshare(CLONE_NEWNET)); >> - clear_cap(_metadata, CAP_SYS_ADMIN); >> - >> - set_ambient_cap(_metadata, CAP_NET_ADMIN); >> - ASSERT_EQ(0, system("ip link set dev lo up")); >> - clear_ambient_cap(_metadata, CAP_NET_ADMIN); >> -} >> - >> static bool is_restricted(const struct protocol_variant *const prot, >> const enum sandbox_type sandbox) >> { >> diff --git a/tools/testing/selftests/landlock/socket_test.c b/tools/testing/selftests/landlock/socket_test.c >> index 67db0e1c1121..2ab27196fa3d 100644 >> --- a/tools/testing/selftests/landlock/socket_test.c >> +++ b/tools/testing/selftests/landlock/socket_test.c >> @@ -11,8 +11,11 @@ >> #include <linux/pfkeyv2.h> >> #include <linux/kcm.h> >> #include <linux/can.h> >> -#include <linux/in.h> >> +#include <sys/socket.h> >> +#include <stdint.h> >> +#include <linux/sctp.h> >> #include <sys/prctl.h> >> +#include <arpa/inet.h> >> >> #include "common.h" >> >> @@ -839,4 +842,101 @@ TEST_F(socket_creation, socketpair) >> } >> } >> >> +static const char loopback_ipv4[] = "127.0.0.1"; >> +static const int backlog = 10; >> +static const int loopback_port = 1024; >> + >> +TEST_F(socket_creation, sctp_peeloff) >> +{ >> + int status, ret; >> + pid_t child; >> + struct sockaddr_in addr; >> + int server_fd; >> + >> + server_fd = >> + socket(AF_INET, SOCK_SEQPACKET | SOCK_CLOEXEC, IPPROTO_SCTP); >> + ASSERT_LE(0, server_fd); >> + >> + addr.sin_family = AF_INET; >> + addr.sin_port = htons(loopback_port); >> + addr.sin_addr.s_addr = inet_addr(loopback_ipv4); >> + >> + ASSERT_EQ(0, bind(server_fd, &addr, sizeof(addr))); >> + ASSERT_EQ(0, listen(server_fd, backlog)); >> + >> + child = fork(); >> + ASSERT_LE(0, child); >> + if (child == 0) { >> + int client_fd; >> + sctp_peeloff_flags_arg_t peeloff; >> + socklen_t peeloff_size = sizeof(peeloff); >> + const struct landlock_ruleset_attr ruleset_attr = { >> + .handled_access_socket = LANDLOCK_ACCESS_SOCKET_CREATE, >> + }; >> + struct landlock_socket_attr sctp_socket_create = { >> + .allowed_access = LANDLOCK_ACCESS_SOCKET_CREATE, >> + .family = AF_INET, >> + .type = SOCK_SEQPACKET, >> + }; >> + >> + /* Closes listening socket for the child. */ >> + ASSERT_EQ(0, close(server_fd)); >> + >> + client_fd = socket(AF_INET, SOCK_SEQPACKET | SOCK_CLOEXEC, >> + IPPROTO_SCTP); >> + ASSERT_LE(0, client_fd); >> + >> + /* >> + * Establishes connection between sockets and >> + * gets SCTP association id. >> + */ >> + ret = setsockopt(client_fd, IPPROTO_SCTP, SCTP_SOCKOPT_CONNECTX, >> + &addr, sizeof(addr)); >> + ASSERT_LE(0, ret); >> + >> + if (self->sandboxed) { >> + /* Denies creation of SCTP sockets. */ >> + int ruleset_fd = landlock_create_ruleset( >> + &ruleset_attr, sizeof(ruleset_attr), 0); >> + ASSERT_LE(0, ruleset_fd); >> + >> + if (self->allowed) { >> + ASSERT_EQ(0, landlock_add_rule( >> + ruleset_fd, >> + LANDLOCK_RULE_SOCKET, >> + &sctp_socket_create, 0)); >> + } >> + enforce_ruleset(_metadata, ruleset_fd); >> + ASSERT_EQ(0, close(ruleset_fd)); >> + } >> + /* >> + * Branches off current SCTP association into a separate socket >> + * and returns it to user space. >> + */ >> + peeloff.p_arg.associd = ret; >> + ret = getsockopt(client_fd, IPPROTO_SCTP, SCTP_SOCKOPT_PEELOFF, >> + &peeloff, &peeloff_size); >> + >> + /* >> + * Creation of SCTP socket by branching off existing SCTP association >> + * should not be restricted by Landlock. >> + */ >> + EXPECT_LE(0, ret); >> + >> + /* Closes peeloff socket if such was created. */ >> + if (!ret) { >> + ASSERT_EQ(0, close(peeloff.p_arg.sd)); >> + } > > Nit: Should this check for (ret >= 0) instead? Ofc, thank you > > I imagine that getsockopt returns -1 on error, normally, > and that would make it past the EXPECT_LE (even if it logs a failure). > > >> + ASSERT_EQ(0, close(client_fd)); >> + _exit(_metadata->exit_code); >> + return; >> + } >> + >> + ASSERT_EQ(child, waitpid(child, &status, 0)); >> + ASSERT_EQ(1, WIFEXITED(status)); >> + ASSERT_EQ(EXIT_SUCCESS, WEXITSTATUS(status)); >> + >> + ASSERT_EQ(0, close(server_fd)); >> +} >> + >> TEST_HARNESS_MAIN >> -- >> 2.34.1 >> > > Reviewed-by: Günther Noack <gnoack@google.com>
diff --git a/tools/testing/selftests/landlock/common.h b/tools/testing/selftests/landlock/common.h index 28df49fa22d5..07d959a8ac7b 100644 --- a/tools/testing/selftests/landlock/common.h +++ b/tools/testing/selftests/landlock/common.h @@ -16,6 +16,7 @@ #include <sys/types.h> #include <sys/wait.h> #include <unistd.h> +#include <sched.h> #include "../kselftest_harness.h" @@ -227,3 +228,14 @@ enforce_ruleset(struct __test_metadata *const _metadata, const int ruleset_fd) TH_LOG("Failed to enforce ruleset: %s", strerror(errno)); } } + +static void setup_loopback(struct __test_metadata *const _metadata) +{ + set_cap(_metadata, CAP_SYS_ADMIN); + ASSERT_EQ(0, unshare(CLONE_NEWNET)); + clear_cap(_metadata, CAP_SYS_ADMIN); + + set_ambient_cap(_metadata, CAP_NET_ADMIN); + ASSERT_EQ(0, system("ip link set dev lo up")); + clear_ambient_cap(_metadata, CAP_NET_ADMIN); +} diff --git a/tools/testing/selftests/landlock/net_test.c b/tools/testing/selftests/landlock/net_test.c index f21cfbbc3638..0b8386657c72 100644 --- a/tools/testing/selftests/landlock/net_test.c +++ b/tools/testing/selftests/landlock/net_test.c @@ -103,17 +103,6 @@ static int set_service(struct service_fixture *const srv, return 1; } -static void setup_loopback(struct __test_metadata *const _metadata) -{ - set_cap(_metadata, CAP_SYS_ADMIN); - ASSERT_EQ(0, unshare(CLONE_NEWNET)); - clear_cap(_metadata, CAP_SYS_ADMIN); - - set_ambient_cap(_metadata, CAP_NET_ADMIN); - ASSERT_EQ(0, system("ip link set dev lo up")); - clear_ambient_cap(_metadata, CAP_NET_ADMIN); -} - static bool is_restricted(const struct protocol_variant *const prot, const enum sandbox_type sandbox) { diff --git a/tools/testing/selftests/landlock/socket_test.c b/tools/testing/selftests/landlock/socket_test.c index 67db0e1c1121..2ab27196fa3d 100644 --- a/tools/testing/selftests/landlock/socket_test.c +++ b/tools/testing/selftests/landlock/socket_test.c @@ -11,8 +11,11 @@ #include <linux/pfkeyv2.h> #include <linux/kcm.h> #include <linux/can.h> -#include <linux/in.h> +#include <sys/socket.h> +#include <stdint.h> +#include <linux/sctp.h> #include <sys/prctl.h> +#include <arpa/inet.h> #include "common.h" @@ -839,4 +842,101 @@ TEST_F(socket_creation, socketpair) } } +static const char loopback_ipv4[] = "127.0.0.1"; +static const int backlog = 10; +static const int loopback_port = 1024; + +TEST_F(socket_creation, sctp_peeloff) +{ + int status, ret; + pid_t child; + struct sockaddr_in addr; + int server_fd; + + server_fd = + socket(AF_INET, SOCK_SEQPACKET | SOCK_CLOEXEC, IPPROTO_SCTP); + ASSERT_LE(0, server_fd); + + addr.sin_family = AF_INET; + addr.sin_port = htons(loopback_port); + addr.sin_addr.s_addr = inet_addr(loopback_ipv4); + + ASSERT_EQ(0, bind(server_fd, &addr, sizeof(addr))); + ASSERT_EQ(0, listen(server_fd, backlog)); + + child = fork(); + ASSERT_LE(0, child); + if (child == 0) { + int client_fd; + sctp_peeloff_flags_arg_t peeloff; + socklen_t peeloff_size = sizeof(peeloff); + const struct landlock_ruleset_attr ruleset_attr = { + .handled_access_socket = LANDLOCK_ACCESS_SOCKET_CREATE, + }; + struct landlock_socket_attr sctp_socket_create = { + .allowed_access = LANDLOCK_ACCESS_SOCKET_CREATE, + .family = AF_INET, + .type = SOCK_SEQPACKET, + }; + + /* Closes listening socket for the child. */ + ASSERT_EQ(0, close(server_fd)); + + client_fd = socket(AF_INET, SOCK_SEQPACKET | SOCK_CLOEXEC, + IPPROTO_SCTP); + ASSERT_LE(0, client_fd); + + /* + * Establishes connection between sockets and + * gets SCTP association id. + */ + ret = setsockopt(client_fd, IPPROTO_SCTP, SCTP_SOCKOPT_CONNECTX, + &addr, sizeof(addr)); + ASSERT_LE(0, ret); + + if (self->sandboxed) { + /* Denies creation of SCTP sockets. */ + int ruleset_fd = landlock_create_ruleset( + &ruleset_attr, sizeof(ruleset_attr), 0); + ASSERT_LE(0, ruleset_fd); + + if (self->allowed) { + ASSERT_EQ(0, landlock_add_rule( + ruleset_fd, + LANDLOCK_RULE_SOCKET, + &sctp_socket_create, 0)); + } + enforce_ruleset(_metadata, ruleset_fd); + ASSERT_EQ(0, close(ruleset_fd)); + } + /* + * Branches off current SCTP association into a separate socket + * and returns it to user space. + */ + peeloff.p_arg.associd = ret; + ret = getsockopt(client_fd, IPPROTO_SCTP, SCTP_SOCKOPT_PEELOFF, + &peeloff, &peeloff_size); + + /* + * Creation of SCTP socket by branching off existing SCTP association + * should not be restricted by Landlock. + */ + EXPECT_LE(0, ret); + + /* Closes peeloff socket if such was created. */ + if (!ret) { + ASSERT_EQ(0, close(peeloff.p_arg.sd)); + } + ASSERT_EQ(0, close(client_fd)); + _exit(_metadata->exit_code); + return; + } + + ASSERT_EQ(child, waitpid(child, &status, 0)); + ASSERT_EQ(1, WIFEXITED(status)); + ASSERT_EQ(EXIT_SUCCESS, WEXITSTATUS(status)); + + ASSERT_EQ(0, close(server_fd)); +} + TEST_HARNESS_MAIN
It is possible to branch off an SCTP UDP association into a separate user space UDP socket. Add test validating that such scenario is not restricted by Landlock. Move setup_loopback() helper from net_test to common.h to use it to enable connection in this test. Signed-off-by: Mikhail Ivanov <ivanov.mikhail1@huawei-partners.com> --- tools/testing/selftests/landlock/common.h | 12 +++ tools/testing/selftests/landlock/net_test.c | 11 -- .../testing/selftests/landlock/socket_test.c | 102 +++++++++++++++++- 3 files changed, 113 insertions(+), 12 deletions(-)