From 1812291e7661673cc29f52b38d9cc39540dee08e Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Fri, 7 Jun 2019 01:49:01 +0200 Subject: [PATCH] bpf: more msg_name rewrite tests to test_sock_addr Extend test_sock_addr for recvmsg test cases, bigger parts of the sendmsg code can be reused for this. Below are the strace view of the recvmsg rewrites; the sendmsg side does not have a BPF prog connected to it for the context of this test: IPv4 test case: [pid 4846] bpf(BPF_PROG_ATTACH, {target_fd=3, attach_bpf_fd=4, attach_type=0x13 /* BPF_??? */, attach_flags=BPF_F_ALLOW_OVERRIDE}, 112) = 0 [pid 4846] socket(AF_INET, SOCK_DGRAM, IPPROTO_IP) = 5 [pid 4846] bind(5, {sa_family=AF_INET, sin_port=htons(4444), sin_addr=inet_addr("127.0.0.1")}, 128) = 0 [pid 4846] socket(AF_INET, SOCK_DGRAM, IPPROTO_IP) = 6 [pid 4846] sendmsg(6, {msg_name={sa_family=AF_INET, sin_port=htons(4444), sin_addr=inet_addr("127.0.0.1")}, msg_namelen=128, msg_iov=[{iov_base="a", iov_len=1}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 1 [pid 4846] select(6, [5], NULL, NULL, {tv_sec=2, tv_usec=0}) = 1 (in [5], left {tv_sec=1, tv_usec=999995}) [pid 4846] recvmsg(5, {msg_name={sa_family=AF_INET, sin_port=htons(4040), sin_addr=inet_addr("192.168.1.254")}, msg_namelen=128->16, msg_iov=[{iov_base="a", iov_len=64}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 1 [pid 4846] close(6) = 0 [pid 4846] close(5) = 0 [pid 4846] bpf(BPF_PROG_DETACH, {target_fd=3, attach_type=0x13 /* BPF_??? */}, 112) = 0 IPv6 test case: [pid 4846] bpf(BPF_PROG_ATTACH, {target_fd=3, attach_bpf_fd=4, attach_type=0x14 /* BPF_??? */, attach_flags=BPF_F_ALLOW_OVERRIDE}, 112) = 0 [pid 4846] socket(AF_INET6, SOCK_DGRAM, IPPROTO_IP) = 5 [pid 4846] bind(5, {sa_family=AF_INET6, sin6_port=htons(6666), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_flowinfo=htonl(0), sin6_scope_id=0}, 128) = 0 [pid 4846] socket(AF_INET6, SOCK_DGRAM, IPPROTO_IP) = 6 [pid 4846] sendmsg(6, {msg_name={sa_family=AF_INET6, sin6_port=htons(6666), inet_pton(AF_INET6, "::1", &sin6_addr), sin6_flowinfo=htonl(0), sin6_scope_id=0}, msg_namelen=128, msg_iov=[{iov_base="a", iov_len=1}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 1 [pid 4846] select(6, [5], NULL, NULL, {tv_sec=2, tv_usec=0}) = 1 (in [5], left {tv_sec=1, tv_usec=999996}) [pid 4846] recvmsg(5, {msg_name={sa_family=AF_INET6, sin6_port=htons(6060), inet_pton(AF_INET6, "face:b00c:1234:5678::abcd", &sin6_addr), sin6_flowinfo=htonl(0), sin6_scope_id=0}, msg_namelen=128->28, msg_iov=[{iov_base="a", iov_len=64}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 1 [pid 4846] close(6) = 0 [pid 4846] close(5) = 0 [pid 4846] bpf(BPF_PROG_DETACH, {target_fd=3, attach_type=0x14 /* BPF_??? */}, 112) = 0 test_sock_addr run w/o strace view: # ./test_sock_addr.sh [...] Test case: recvmsg4: return code ok .. [PASS] Test case: recvmsg4: return code !ok .. [PASS] Test case: recvmsg6: return code ok .. [PASS] Test case: recvmsg6: return code !ok .. [PASS] Test case: recvmsg4: rewrite IP & port (asm) .. [PASS] Test case: recvmsg6: rewrite IP & port (asm) .. [PASS] [...] Signed-off-by: Daniel Borkmann Acked-by: Andrey Ignatov Acked-by: Martin KaFai Lau Signed-off-by: Alexei Starovoitov --- tools/testing/selftests/bpf/test_sock_addr.c | 213 +++++++++++++++++-- 1 file changed, 197 insertions(+), 16 deletions(-) diff --git a/tools/testing/selftests/bpf/test_sock_addr.c b/tools/testing/selftests/bpf/test_sock_addr.c index 3f110eaaf29c..4ecde2392327 100644 --- a/tools/testing/selftests/bpf/test_sock_addr.c +++ b/tools/testing/selftests/bpf/test_sock_addr.c @@ -76,6 +76,7 @@ struct sock_addr_test { enum { LOAD_REJECT, ATTACH_REJECT, + ATTACH_OKAY, SYSCALL_EPERM, SYSCALL_ENOTSUPP, SUCCESS, @@ -88,9 +89,13 @@ static int connect4_prog_load(const struct sock_addr_test *test); static int connect6_prog_load(const struct sock_addr_test *test); static int sendmsg_allow_prog_load(const struct sock_addr_test *test); static int sendmsg_deny_prog_load(const struct sock_addr_test *test); +static int recvmsg_allow_prog_load(const struct sock_addr_test *test); +static int recvmsg_deny_prog_load(const struct sock_addr_test *test); static int sendmsg4_rw_asm_prog_load(const struct sock_addr_test *test); +static int recvmsg4_rw_asm_prog_load(const struct sock_addr_test *test); static int sendmsg4_rw_c_prog_load(const struct sock_addr_test *test); static int sendmsg6_rw_asm_prog_load(const struct sock_addr_test *test); +static int recvmsg6_rw_asm_prog_load(const struct sock_addr_test *test); static int sendmsg6_rw_c_prog_load(const struct sock_addr_test *test); static int sendmsg6_rw_v4mapped_prog_load(const struct sock_addr_test *test); static int sendmsg6_rw_wildcard_prog_load(const struct sock_addr_test *test); @@ -507,6 +512,92 @@ static struct sock_addr_test tests[] = { SRC6_REWRITE_IP, SYSCALL_EPERM, }, + + /* recvmsg */ + { + "recvmsg4: return code ok", + recvmsg_allow_prog_load, + BPF_CGROUP_UDP4_RECVMSG, + BPF_CGROUP_UDP4_RECVMSG, + AF_INET, + SOCK_DGRAM, + NULL, + 0, + NULL, + 0, + NULL, + ATTACH_OKAY, + }, + { + "recvmsg4: return code !ok", + recvmsg_deny_prog_load, + BPF_CGROUP_UDP4_RECVMSG, + BPF_CGROUP_UDP4_RECVMSG, + AF_INET, + SOCK_DGRAM, + NULL, + 0, + NULL, + 0, + NULL, + LOAD_REJECT, + }, + { + "recvmsg6: return code ok", + recvmsg_allow_prog_load, + BPF_CGROUP_UDP6_RECVMSG, + BPF_CGROUP_UDP6_RECVMSG, + AF_INET6, + SOCK_DGRAM, + NULL, + 0, + NULL, + 0, + NULL, + ATTACH_OKAY, + }, + { + "recvmsg6: return code !ok", + recvmsg_deny_prog_load, + BPF_CGROUP_UDP6_RECVMSG, + BPF_CGROUP_UDP6_RECVMSG, + AF_INET6, + SOCK_DGRAM, + NULL, + 0, + NULL, + 0, + NULL, + LOAD_REJECT, + }, + { + "recvmsg4: rewrite IP & port (asm)", + recvmsg4_rw_asm_prog_load, + BPF_CGROUP_UDP4_RECVMSG, + BPF_CGROUP_UDP4_RECVMSG, + AF_INET, + SOCK_DGRAM, + SERV4_REWRITE_IP, + SERV4_REWRITE_PORT, + SERV4_REWRITE_IP, + SERV4_REWRITE_PORT, + SERV4_IP, + SUCCESS, + }, + { + "recvmsg6: rewrite IP & port (asm)", + recvmsg6_rw_asm_prog_load, + BPF_CGROUP_UDP6_RECVMSG, + BPF_CGROUP_UDP6_RECVMSG, + AF_INET6, + SOCK_DGRAM, + SERV6_REWRITE_IP, + SERV6_REWRITE_PORT, + SERV6_REWRITE_IP, + SERV6_REWRITE_PORT, + SERV6_IP, + SUCCESS, + }, }; static int mk_sockaddr(int domain, const char *ip, unsigned short port, @@ -765,8 +856,8 @@ static int connect6_prog_load(const struct sock_addr_test *test) return load_path(test, CONNECT6_PROG_PATH); } -static int sendmsg_ret_only_prog_load(const struct sock_addr_test *test, - int32_t rc) +static int xmsg_ret_only_prog_load(const struct sock_addr_test *test, + int32_t rc) { struct bpf_insn insns[] = { /* return rc */ @@ -778,12 +869,22 @@ static int sendmsg_ret_only_prog_load(const struct sock_addr_test *test, static int sendmsg_allow_prog_load(const struct sock_addr_test *test) { - return sendmsg_ret_only_prog_load(test, /*rc*/ 1); + return xmsg_ret_only_prog_load(test, /*rc*/ 1); } static int sendmsg_deny_prog_load(const struct sock_addr_test *test) { - return sendmsg_ret_only_prog_load(test, /*rc*/ 0); + return xmsg_ret_only_prog_load(test, /*rc*/ 0); +} + +static int recvmsg_allow_prog_load(const struct sock_addr_test *test) +{ + return xmsg_ret_only_prog_load(test, /*rc*/ 1); +} + +static int recvmsg_deny_prog_load(const struct sock_addr_test *test) +{ + return xmsg_ret_only_prog_load(test, /*rc*/ 0); } static int sendmsg4_rw_asm_prog_load(const struct sock_addr_test *test) @@ -838,6 +939,47 @@ static int sendmsg4_rw_asm_prog_load(const struct sock_addr_test *test) return load_insns(test, insns, sizeof(insns) / sizeof(struct bpf_insn)); } +static int recvmsg4_rw_asm_prog_load(const struct sock_addr_test *test) +{ + struct sockaddr_in src4_rw_addr; + + if (mk_sockaddr(AF_INET, SERV4_IP, SERV4_PORT, + (struct sockaddr *)&src4_rw_addr, + sizeof(src4_rw_addr)) == -1) + return -1; + + struct bpf_insn insns[] = { + BPF_MOV64_REG(BPF_REG_6, BPF_REG_1), + + /* if (sk.family == AF_INET && */ + BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6, + offsetof(struct bpf_sock_addr, family)), + BPF_JMP_IMM(BPF_JNE, BPF_REG_7, AF_INET, 6), + + /* sk.type == SOCK_DGRAM) { */ + BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6, + offsetof(struct bpf_sock_addr, type)), + BPF_JMP_IMM(BPF_JNE, BPF_REG_7, SOCK_DGRAM, 4), + + /* user_ip4 = src4_rw_addr.sin_addr */ + BPF_MOV32_IMM(BPF_REG_7, src4_rw_addr.sin_addr.s_addr), + BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7, + offsetof(struct bpf_sock_addr, user_ip4)), + + /* user_port = src4_rw_addr.sin_port */ + BPF_MOV32_IMM(BPF_REG_7, src4_rw_addr.sin_port), + BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7, + offsetof(struct bpf_sock_addr, user_port)), + /* } */ + + /* return 1 */ + BPF_MOV64_IMM(BPF_REG_0, 1), + BPF_EXIT_INSN(), + }; + + return load_insns(test, insns, sizeof(insns) / sizeof(struct bpf_insn)); +} + static int sendmsg4_rw_c_prog_load(const struct sock_addr_test *test) { return load_path(test, SENDMSG4_PROG_PATH); @@ -901,6 +1043,39 @@ static int sendmsg6_rw_asm_prog_load(const struct sock_addr_test *test) return sendmsg6_rw_dst_asm_prog_load(test, SERV6_REWRITE_IP); } +static int recvmsg6_rw_asm_prog_load(const struct sock_addr_test *test) +{ + struct sockaddr_in6 src6_rw_addr; + + if (mk_sockaddr(AF_INET6, SERV6_IP, SERV6_PORT, + (struct sockaddr *)&src6_rw_addr, + sizeof(src6_rw_addr)) == -1) + return -1; + + struct bpf_insn insns[] = { + BPF_MOV64_REG(BPF_REG_6, BPF_REG_1), + + /* if (sk.family == AF_INET6) { */ + BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6, + offsetof(struct bpf_sock_addr, family)), + BPF_JMP_IMM(BPF_JNE, BPF_REG_7, AF_INET6, 10), + + STORE_IPV6(user_ip6, src6_rw_addr.sin6_addr.s6_addr32), + + /* user_port = dst6_rw_addr.sin6_port */ + BPF_MOV32_IMM(BPF_REG_7, src6_rw_addr.sin6_port), + BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7, + offsetof(struct bpf_sock_addr, user_port)), + /* } */ + + /* return 1 */ + BPF_MOV64_IMM(BPF_REG_0, 1), + BPF_EXIT_INSN(), + }; + + return load_insns(test, insns, sizeof(insns) / sizeof(struct bpf_insn)); +} + static int sendmsg6_rw_v4mapped_prog_load(const struct sock_addr_test *test) { return sendmsg6_rw_dst_asm_prog_load(test, SERV6_V4MAPPED_IP); @@ -1282,13 +1457,13 @@ out: return err; } -static int run_sendmsg_test_case(const struct sock_addr_test *test) +static int run_xmsg_test_case(const struct sock_addr_test *test, int max_cmsg) { socklen_t addr_len = sizeof(struct sockaddr_storage); - struct sockaddr_storage expected_src_addr; - struct sockaddr_storage requested_addr; struct sockaddr_storage expected_addr; - struct sockaddr_storage real_src_addr; + struct sockaddr_storage server_addr; + struct sockaddr_storage sendmsg_addr; + struct sockaddr_storage recvmsg_addr; int clientfd = -1; int servfd = -1; int set_cmsg; @@ -1297,20 +1472,19 @@ static int run_sendmsg_test_case(const struct sock_addr_test *test) if (test->type != SOCK_DGRAM) goto err; - if (init_addrs(test, &requested_addr, &expected_addr, - &expected_src_addr)) + if (init_addrs(test, &sendmsg_addr, &server_addr, &expected_addr)) goto err; /* Prepare server to sendmsg to */ - servfd = start_server(test->type, &expected_addr, addr_len); + servfd = start_server(test->type, &server_addr, addr_len); if (servfd == -1) goto err; - for (set_cmsg = 0; set_cmsg <= 1; ++set_cmsg) { + for (set_cmsg = 0; set_cmsg <= max_cmsg; ++set_cmsg) { if (clientfd >= 0) close(clientfd); - clientfd = sendmsg_to_server(test->type, &requested_addr, + clientfd = sendmsg_to_server(test->type, &sendmsg_addr, addr_len, set_cmsg, /*flags*/0, &err); if (err) @@ -1330,10 +1504,10 @@ static int run_sendmsg_test_case(const struct sock_addr_test *test) * specific packet may differ from the one used by default and * returned by getsockname(2). */ - if (recvmsg_from_client(servfd, &real_src_addr) == -1) + if (recvmsg_from_client(servfd, &recvmsg_addr) == -1) goto err; - if (cmp_addr(&real_src_addr, &expected_src_addr, /*cmp_port*/0)) + if (cmp_addr(&recvmsg_addr, &expected_addr, /*cmp_port*/0)) goto err; } @@ -1366,6 +1540,9 @@ static int run_test_case(int cgfd, const struct sock_addr_test *test) goto out; } else if (test->expected_result == ATTACH_REJECT || err) { goto err; + } else if (test->expected_result == ATTACH_OKAY) { + err = 0; + goto out; } switch (test->attach_type) { @@ -1379,7 +1556,11 @@ static int run_test_case(int cgfd, const struct sock_addr_test *test) break; case BPF_CGROUP_UDP4_SENDMSG: case BPF_CGROUP_UDP6_SENDMSG: - err = run_sendmsg_test_case(test); + err = run_xmsg_test_case(test, 1); + break; + case BPF_CGROUP_UDP4_RECVMSG: + case BPF_CGROUP_UDP6_RECVMSG: + err = run_xmsg_test_case(test, 0); break; default: goto err; -- 2.30.2