// SPDX-License-Identifier: GPL-2.0 // Copyright (c) 2018 Facebook #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include "cgroup_helpers.h" #include "bpf_rlimit.h" #ifndef ENOTSUPP # define ENOTSUPP 524 #endif #ifndef ARRAY_SIZE # define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) #endif #define CG_PATH "/foo" #define CONNECT4_PROG_PATH "./connect4_prog.o" #define CONNECT6_PROG_PATH "./connect6_prog.o" #define SENDMSG4_PROG_PATH "./sendmsg4_prog.o" #define SENDMSG6_PROG_PATH "./sendmsg6_prog.o" #define SERV4_IP "192.168.1.254" #define SERV4_REWRITE_IP "127.0.0.1" #define SRC4_IP "172.16.0.1" #define SRC4_REWRITE_IP "127.0.0.4" #define SERV4_PORT 4040 #define SERV4_REWRITE_PORT 4444 #define SERV6_IP "face:b00c:1234:5678::abcd" #define SERV6_REWRITE_IP "::1" #define SERV6_V4MAPPED_IP "::ffff:192.168.0.4" #define SRC6_IP "::1" #define SRC6_REWRITE_IP "::6" #define SERV6_PORT 6060 #define SERV6_REWRITE_PORT 6666 #define INET_NTOP_BUF 40 struct sock_addr_test; typedef int (*load_fn)(const struct sock_addr_test *test); typedef int (*info_fn)(int, struct sockaddr *, socklen_t *); char bpf_log_buf[BPF_LOG_BUF_SIZE]; struct sock_addr_test { const char *descr; /* BPF prog properties */ load_fn loadfn; enum bpf_attach_type expected_attach_type; enum bpf_attach_type attach_type; /* Socket properties */ int domain; int type; /* IP:port pairs for BPF prog to override */ const char *requested_ip; unsigned short requested_port; const char *expected_ip; unsigned short expected_port; const char *expected_src_ip; /* Expected test result */ enum { LOAD_REJECT, ATTACH_REJECT, SYSCALL_EPERM, SYSCALL_ENOTSUPP, SUCCESS, } expected_result; }; static int bind4_prog_load(const struct sock_addr_test *test); static int bind6_prog_load(const struct sock_addr_test *test); 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_deny_prog_load(const struct sock_addr_test *test); static int sendmsg4_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 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 struct sock_addr_test tests[] = { /* bind */ { "bind4: load prog with wrong expected attach type", bind4_prog_load, BPF_CGROUP_INET6_BIND, BPF_CGROUP_INET4_BIND, AF_INET, SOCK_STREAM, NULL, 0, NULL, 0, NULL, LOAD_REJECT, }, { "bind4: attach prog with wrong attach type", bind4_prog_load, BPF_CGROUP_INET4_BIND, BPF_CGROUP_INET6_BIND, AF_INET, SOCK_STREAM, NULL, 0, NULL, 0, NULL, ATTACH_REJECT, }, { "bind4: rewrite IP & TCP port in", bind4_prog_load, BPF_CGROUP_INET4_BIND, BPF_CGROUP_INET4_BIND, AF_INET, SOCK_STREAM, SERV4_IP, SERV4_PORT, SERV4_REWRITE_IP, SERV4_REWRITE_PORT, NULL, SUCCESS, }, { "bind4: rewrite IP & UDP port in", bind4_prog_load, BPF_CGROUP_INET4_BIND, BPF_CGROUP_INET4_BIND, AF_INET, SOCK_DGRAM, SERV4_IP, SERV4_PORT, SERV4_REWRITE_IP, SERV4_REWRITE_PORT, NULL, SUCCESS, }, { "bind6: load prog with wrong expected attach type", bind6_prog_load, BPF_CGROUP_INET4_BIND, BPF_CGROUP_INET6_BIND, AF_INET6, SOCK_STREAM, NULL, 0, NULL, 0, NULL, LOAD_REJECT, }, { "bind6: attach prog with wrong attach type", bind6_prog_load, BPF_CGROUP_INET6_BIND, BPF_CGROUP_INET4_BIND, AF_INET, SOCK_STREAM, NULL, 0, NULL, 0, NULL, ATTACH_REJECT, }, { "bind6: rewrite IP & TCP port in", bind6_prog_load, BPF_CGROUP_INET6_BIND, BPF_CGROUP_INET6_BIND, AF_INET6, SOCK_STREAM, SERV6_IP, SERV6_PORT, SERV6_REWRITE_IP, SERV6_REWRITE_PORT, NULL, SUCCESS, }, { "bind6: rewrite IP & UDP port in", bind6_prog_load, BPF_CGROUP_INET6_BIND, BPF_CGROUP_INET6_BIND, AF_INET6, SOCK_DGRAM, SERV6_IP, SERV6_PORT, SERV6_REWRITE_IP, SERV6_REWRITE_PORT, NULL, SUCCESS, }, /* connect */ { "connect4: load prog with wrong expected attach type", connect4_prog_load, BPF_CGROUP_INET6_CONNECT, BPF_CGROUP_INET4_CONNECT, AF_INET, SOCK_STREAM, NULL, 0, NULL, 0, NULL, LOAD_REJECT, }, { "connect4: attach prog with wrong attach type", connect4_prog_load, BPF_CGROUP_INET4_CONNECT, BPF_CGROUP_INET6_CONNECT, AF_INET, SOCK_STREAM, NULL, 0, NULL, 0, NULL, ATTACH_REJECT, }, { "connect4: rewrite IP & TCP port", connect4_prog_load, BPF_CGROUP_INET4_CONNECT, BPF_CGROUP_INET4_CONNECT, AF_INET, SOCK_STREAM, SERV4_IP, SERV4_PORT, SERV4_REWRITE_IP, SERV4_REWRITE_PORT, SRC4_REWRITE_IP, SUCCESS, }, { "connect4: rewrite IP & UDP port", connect4_prog_load, BPF_CGROUP_INET4_CONNECT, BPF_CGROUP_INET4_CONNECT, AF_INET, SOCK_DGRAM, SERV4_IP, SERV4_PORT, SERV4_REWRITE_IP, SERV4_REWRITE_PORT, SRC4_REWRITE_IP, SUCCESS, }, { "connect6: load prog with wrong expected attach type", connect6_prog_load, BPF_CGROUP_INET4_CONNECT, BPF_CGROUP_INET6_CONNECT, AF_INET6, SOCK_STREAM, NULL, 0, NULL, 0, NULL, LOAD_REJECT, }, { "connect6: attach prog with wrong attach type", connect6_prog_load, BPF_CGROUP_INET6_CONNECT, BPF_CGROUP_INET4_CONNECT, AF_INET, SOCK_STREAM, NULL, 0, NULL, 0, NULL, ATTACH_REJECT, }, { "connect6: rewrite IP & TCP port", connect6_prog_load, BPF_CGROUP_INET6_CONNECT, BPF_CGROUP_INET6_CONNECT, AF_INET6, SOCK_STREAM, SERV6_IP, SERV6_PORT, SERV6_REWRITE_IP, SERV6_REWRITE_PORT, SRC6_REWRITE_IP, SUCCESS, }, { "connect6: rewrite IP & UDP port", connect6_prog_load, BPF_CGROUP_INET6_CONNECT, BPF_CGROUP_INET6_CONNECT, AF_INET6, SOCK_DGRAM, SERV6_IP, SERV6_PORT, SERV6_REWRITE_IP, SERV6_REWRITE_PORT, SRC6_REWRITE_IP, SUCCESS, }, /* sendmsg */ { "sendmsg4: load prog with wrong expected attach type", sendmsg4_rw_asm_prog_load, BPF_CGROUP_UDP6_SENDMSG, BPF_CGROUP_UDP4_SENDMSG, AF_INET, SOCK_DGRAM, NULL, 0, NULL, 0, NULL, LOAD_REJECT, }, { "sendmsg4: attach prog with wrong attach type", sendmsg4_rw_asm_prog_load, BPF_CGROUP_UDP4_SENDMSG, BPF_CGROUP_UDP6_SENDMSG, AF_INET, SOCK_DGRAM, NULL, 0, NULL, 0, NULL, ATTACH_REJECT, }, { "sendmsg4: rewrite IP & port (asm)", sendmsg4_rw_asm_prog_load, BPF_CGROUP_UDP4_SENDMSG, BPF_CGROUP_UDP4_SENDMSG, AF_INET, SOCK_DGRAM, SERV4_IP, SERV4_PORT, SERV4_REWRITE_IP, SERV4_REWRITE_PORT, SRC4_REWRITE_IP, SUCCESS, }, { "sendmsg4: rewrite IP & port (C)", sendmsg4_rw_c_prog_load, BPF_CGROUP_UDP4_SENDMSG, BPF_CGROUP_UDP4_SENDMSG, AF_INET, SOCK_DGRAM, SERV4_IP, SERV4_PORT, SERV4_REWRITE_IP, SERV4_REWRITE_PORT, SRC4_REWRITE_IP, SUCCESS, }, { "sendmsg4: deny call", sendmsg_deny_prog_load, BPF_CGROUP_UDP4_SENDMSG, BPF_CGROUP_UDP4_SENDMSG, AF_INET, SOCK_DGRAM, SERV4_IP, SERV4_PORT, SERV4_REWRITE_IP, SERV4_REWRITE_PORT, SRC4_REWRITE_IP, SYSCALL_EPERM, }, { "sendmsg6: load prog with wrong expected attach type", sendmsg6_rw_asm_prog_load, BPF_CGROUP_UDP4_SENDMSG, BPF_CGROUP_UDP6_SENDMSG, AF_INET6, SOCK_DGRAM, NULL, 0, NULL, 0, NULL, LOAD_REJECT, }, { "sendmsg6: attach prog with wrong attach type", sendmsg6_rw_asm_prog_load, BPF_CGROUP_UDP6_SENDMSG, BPF_CGROUP_UDP4_SENDMSG, AF_INET6, SOCK_DGRAM, NULL, 0, NULL, 0, NULL, ATTACH_REJECT, }, { "sendmsg6: rewrite IP & port (asm)", sendmsg6_rw_asm_prog_load, BPF_CGROUP_UDP6_SENDMSG, BPF_CGROUP_UDP6_SENDMSG, AF_INET6, SOCK_DGRAM, SERV6_IP, SERV6_PORT, SERV6_REWRITE_IP, SERV6_REWRITE_PORT, SRC6_REWRITE_IP, SUCCESS, }, { "sendmsg6: rewrite IP & port (C)", sendmsg6_rw_c_prog_load, BPF_CGROUP_UDP6_SENDMSG, BPF_CGROUP_UDP6_SENDMSG, AF_INET6, SOCK_DGRAM, SERV6_IP, SERV6_PORT, SERV6_REWRITE_IP, SERV6_REWRITE_PORT, SRC6_REWRITE_IP, SUCCESS, }, { "sendmsg6: IPv4-mapped IPv6", sendmsg6_rw_v4mapped_prog_load, BPF_CGROUP_UDP6_SENDMSG, BPF_CGROUP_UDP6_SENDMSG, AF_INET6, SOCK_DGRAM, SERV6_IP, SERV6_PORT, SERV6_REWRITE_IP, SERV6_REWRITE_PORT, SRC6_REWRITE_IP, SYSCALL_ENOTSUPP, }, { "sendmsg6: deny call", sendmsg_deny_prog_load, BPF_CGROUP_UDP6_SENDMSG, BPF_CGROUP_UDP6_SENDMSG, AF_INET6, SOCK_DGRAM, SERV6_IP, SERV6_PORT, SERV6_REWRITE_IP, SERV6_REWRITE_PORT, SRC6_REWRITE_IP, SYSCALL_EPERM, }, }; static int mk_sockaddr(int domain, const char *ip, unsigned short port, struct sockaddr *addr, socklen_t addr_len) { struct sockaddr_in6 *addr6; struct sockaddr_in *addr4; if (domain != AF_INET && domain != AF_INET6) { log_err("Unsupported address family"); return -1; } memset(addr, 0, addr_len); if (domain == AF_INET) { if (addr_len < sizeof(struct sockaddr_in)) return -1; addr4 = (struct sockaddr_in *)addr; addr4->sin_family = domain; addr4->sin_port = htons(port); if (inet_pton(domain, ip, (void *)&addr4->sin_addr) != 1) { log_err("Invalid IPv4: %s", ip); return -1; } } else if (domain == AF_INET6) { if (addr_len < sizeof(struct sockaddr_in6)) return -1; addr6 = (struct sockaddr_in6 *)addr; addr6->sin6_family = domain; addr6->sin6_port = htons(port); if (inet_pton(domain, ip, (void *)&addr6->sin6_addr) != 1) { log_err("Invalid IPv6: %s", ip); return -1; } } return 0; } static int load_insns(const struct sock_addr_test *test, const struct bpf_insn *insns, size_t insns_cnt) { struct bpf_load_program_attr load_attr; int ret; memset(&load_attr, 0, sizeof(struct bpf_load_program_attr)); load_attr.prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR; load_attr.expected_attach_type = test->expected_attach_type; load_attr.insns = insns; load_attr.insns_cnt = insns_cnt; load_attr.license = "GPL"; ret = bpf_load_program_xattr(&load_attr, bpf_log_buf, BPF_LOG_BUF_SIZE); if (ret < 0 && test->expected_result != LOAD_REJECT) { log_err(">>> Loading program error.\n" ">>> Verifier output:\n%s\n-------\n", bpf_log_buf); } return ret; } /* [1] These testing programs try to read different context fields, including * narrow loads of different sizes from user_ip4 and user_ip6, and write to * those allowed to be overridden. * * [2] BPF_LD_IMM64 & BPF_JMP_REG are used below whenever there is a need to * compare a register with unsigned 32bit integer. BPF_JMP_IMM can't be used * in such cases since it accepts only _signed_ 32bit integer as IMM * argument. Also note that BPF_LD_IMM64 contains 2 instructions what matters * to count jumps properly. */ static int bind4_prog_load(const struct sock_addr_test *test) { union { uint8_t u4_addr8[4]; uint16_t u4_addr16[2]; uint32_t u4_addr32; } ip4; struct sockaddr_in addr4_rw; if (inet_pton(AF_INET, SERV4_IP, (void *)&ip4) != 1) { log_err("Invalid IPv4: %s", SERV4_IP); return -1; } if (mk_sockaddr(AF_INET, SERV4_REWRITE_IP, SERV4_REWRITE_PORT, (struct sockaddr *)&addr4_rw, sizeof(addr4_rw)) == -1) return -1; /* See [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, 16), /* (sk.type == SOCK_DGRAM || sk.type == SOCK_STREAM) && */ 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, 1), BPF_JMP_A(1), BPF_JMP_IMM(BPF_JNE, BPF_REG_7, SOCK_STREAM, 12), /* 1st_byte_of_user_ip4 == expected && */ BPF_LDX_MEM(BPF_B, BPF_REG_7, BPF_REG_6, offsetof(struct bpf_sock_addr, user_ip4)), BPF_JMP_IMM(BPF_JNE, BPF_REG_7, ip4.u4_addr8[0], 10), /* 1st_half_of_user_ip4 == expected && */ BPF_LDX_MEM(BPF_H, BPF_REG_7, BPF_REG_6, offsetof(struct bpf_sock_addr, user_ip4)), BPF_JMP_IMM(BPF_JNE, BPF_REG_7, ip4.u4_addr16[0], 8), /* whole_user_ip4 == expected) { */ BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6, offsetof(struct bpf_sock_addr, user_ip4)), BPF_LD_IMM64(BPF_REG_8, ip4.u4_addr32), /* See [2]. */ BPF_JMP_REG(BPF_JNE, BPF_REG_7, BPF_REG_8, 4), /* user_ip4 = addr4_rw.sin_addr */ BPF_MOV32_IMM(BPF_REG_7, addr4_rw.sin_addr.s_addr), BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7, offsetof(struct bpf_sock_addr, user_ip4)), /* user_port = addr4_rw.sin_port */ BPF_MOV32_IMM(BPF_REG_7, addr4_rw.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 bind6_prog_load(const struct sock_addr_test *test) { struct sockaddr_in6 addr6_rw; struct in6_addr ip6; if (inet_pton(AF_INET6, SERV6_IP, (void *)&ip6) != 1) { log_err("Invalid IPv6: %s", SERV6_IP); return -1; } if (mk_sockaddr(AF_INET6, SERV6_REWRITE_IP, SERV6_REWRITE_PORT, (struct sockaddr *)&addr6_rw, sizeof(addr6_rw)) == -1) return -1; /* See [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, 18), /* 5th_byte_of_user_ip6 == expected && */ BPF_LDX_MEM(BPF_B, BPF_REG_7, BPF_REG_6, offsetof(struct bpf_sock_addr, user_ip6[1])), BPF_JMP_IMM(BPF_JNE, BPF_REG_7, ip6.s6_addr[4], 16), /* 3rd_half_of_user_ip6 == expected && */ BPF_LDX_MEM(BPF_H, BPF_REG_7, BPF_REG_6, offsetof(struct bpf_sock_addr, user_ip6[1])), BPF_JMP_IMM(BPF_JNE, BPF_REG_7, ip6.s6_addr16[2], 14), /* last_word_of_user_ip6 == expected) { */ BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6, offsetof(struct bpf_sock_addr, user_ip6[3])), BPF_LD_IMM64(BPF_REG_8, ip6.s6_addr32[3]), /* See [2]. */ BPF_JMP_REG(BPF_JNE, BPF_REG_7, BPF_REG_8, 10), #define STORE_IPV6_WORD(N) \ BPF_MOV32_IMM(BPF_REG_7, addr6_rw.sin6_addr.s6_addr32[N]), \ BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7, \ offsetof(struct bpf_sock_addr, user_ip6[N])) /* user_ip6 = addr6_rw.sin6_addr */ STORE_IPV6_WORD(0), STORE_IPV6_WORD(1), STORE_IPV6_WORD(2), STORE_IPV6_WORD(3), /* user_port = addr6_rw.sin6_port */ BPF_MOV32_IMM(BPF_REG_7, addr6_rw.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 load_path(const struct sock_addr_test *test, const char *path) { struct bpf_prog_load_attr attr; struct bpf_object *obj; int prog_fd; memset(&attr, 0, sizeof(struct bpf_prog_load_attr)); attr.file = path; attr.prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR; attr.expected_attach_type = test->expected_attach_type; if (bpf_prog_load_xattr(&attr, &obj, &prog_fd)) { if (test->expected_result != LOAD_REJECT) log_err(">>> Loading program (%s) error.\n", path); return -1; } return prog_fd; } static int connect4_prog_load(const struct sock_addr_test *test) { return load_path(test, CONNECT4_PROG_PATH); } static int connect6_prog_load(const struct sock_addr_test *test) { return load_path(test, CONNECT6_PROG_PATH); } static int sendmsg_deny_prog_load(const struct sock_addr_test *test) { struct bpf_insn insns[] = { /* return 0 */ BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN(), }; return load_insns(test, insns, sizeof(insns) / sizeof(struct bpf_insn)); } static int sendmsg4_rw_asm_prog_load(const struct sock_addr_test *test) { struct sockaddr_in dst4_rw_addr; struct in_addr src4_rw_ip; if (inet_pton(AF_INET, SRC4_REWRITE_IP, (void *)&src4_rw_ip) != 1) { log_err("Invalid IPv4: %s", SRC4_REWRITE_IP); return -1; } if (mk_sockaddr(AF_INET, SERV4_REWRITE_IP, SERV4_REWRITE_PORT, (struct sockaddr *)&dst4_rw_addr, sizeof(dst4_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, 8), /* 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, 6), /* msg_src_ip4 = src4_rw_ip */ BPF_MOV32_IMM(BPF_REG_7, src4_rw_ip.s_addr), BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7, offsetof(struct bpf_sock_addr, msg_src_ip4)), /* user_ip4 = dst4_rw_addr.sin_addr */ BPF_MOV32_IMM(BPF_REG_7, dst4_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 = dst4_rw_addr.sin_port */ BPF_MOV32_IMM(BPF_REG_7, dst4_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); } static int sendmsg6_rw_dst_asm_prog_load(const struct sock_addr_test *test, const char *rw_dst_ip) { struct sockaddr_in6 dst6_rw_addr; struct in6_addr src6_rw_ip; if (inet_pton(AF_INET6, SRC6_REWRITE_IP, (void *)&src6_rw_ip) != 1) { log_err("Invalid IPv6: %s", SRC6_REWRITE_IP); return -1; } if (mk_sockaddr(AF_INET6, rw_dst_ip, SERV6_REWRITE_PORT, (struct sockaddr *)&dst6_rw_addr, sizeof(dst6_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, 18), #define STORE_IPV6_WORD_N(DST, SRC, N) \ BPF_MOV32_IMM(BPF_REG_7, SRC[N]), \ BPF_STX_MEM(BPF_W, BPF_REG_6, BPF_REG_7, \ offsetof(struct bpf_sock_addr, DST[N])) #define STORE_IPV6(DST, SRC) \ STORE_IPV6_WORD_N(DST, SRC, 0), \ STORE_IPV6_WORD_N(DST, SRC, 1), \ STORE_IPV6_WORD_N(DST, SRC, 2), \ STORE_IPV6_WORD_N(DST, SRC, 3) STORE_IPV6(msg_src_ip6, src6_rw_ip.s6_addr32), STORE_IPV6(user_ip6, dst6_rw_addr.sin6_addr.s6_addr32), /* user_port = dst6_rw_addr.sin6_port */ BPF_MOV32_IMM(BPF_REG_7, dst6_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_asm_prog_load(const struct sock_addr_test *test) { return sendmsg6_rw_dst_asm_prog_load(test, SERV6_REWRITE_IP); } static int sendmsg6_rw_v4mapped_prog_load(const struct sock_addr_test *test) { return sendmsg6_rw_dst_asm_prog_load(test, SERV6_V4MAPPED_IP); } static int sendmsg6_rw_c_prog_load(const struct sock_addr_test *test) { return load_path(test, SENDMSG6_PROG_PATH); } static int cmp_addr(const struct sockaddr_storage *addr1, const struct sockaddr_storage *addr2, int cmp_port) { const struct sockaddr_in *four1, *four2; const struct sockaddr_in6 *six1, *six2; if (addr1->ss_family != addr2->ss_family) return -1; if (addr1->ss_family == AF_INET) { four1 = (const struct sockaddr_in *)addr1; four2 = (const struct sockaddr_in *)addr2; return !((four1->sin_port == four2->sin_port || !cmp_port) && four1->sin_addr.s_addr == four2->sin_addr.s_addr); } else if (addr1->ss_family == AF_INET6) { six1 = (const struct sockaddr_in6 *)addr1; six2 = (const struct sockaddr_in6 *)addr2; return !((six1->sin6_port == six2->sin6_port || !cmp_port) && !memcmp(&six1->sin6_addr, &six2->sin6_addr, sizeof(struct in6_addr))); } return -1; } static int cmp_sock_addr(info_fn fn, int sock1, const struct sockaddr_storage *addr2, int cmp_port) { struct sockaddr_storage addr1; socklen_t len1 = sizeof(addr1); memset(&addr1, 0, len1); if (fn(sock1, (struct sockaddr *)&addr1, (socklen_t *)&len1) != 0) return -1; return cmp_addr(&addr1, addr2, cmp_port); } static int cmp_local_ip(int sock1, const struct sockaddr_storage *addr2) { return cmp_sock_addr(getsockname, sock1, addr2, /*cmp_port*/ 0); } static int cmp_local_addr(int sock1, const struct sockaddr_storage *addr2) { return cmp_sock_addr(getsockname, sock1, addr2, /*cmp_port*/ 1); } static int cmp_peer_addr(int sock1, const struct sockaddr_storage *addr2) { return cmp_sock_addr(getpeername, sock1, addr2, /*cmp_port*/ 1); } static int start_server(int type, const struct sockaddr_storage *addr, socklen_t addr_len) { int fd; fd = socket(addr->ss_family, type, 0); if (fd == -1) { log_err("Failed to create server socket"); goto out; } if (bind(fd, (const struct sockaddr *)addr, addr_len) == -1) { log_err("Failed to bind server socket"); goto close_out; } if (type == SOCK_STREAM) { if (listen(fd, 128) == -1) { log_err("Failed to listen on server socket"); goto close_out; } } goto out; close_out: close(fd); fd = -1; out: return fd; } static int connect_to_server(int type, const struct sockaddr_storage *addr, socklen_t addr_len) { int domain; int fd = -1; domain = addr->ss_family; if (domain != AF_INET && domain != AF_INET6) { log_err("Unsupported address family"); goto err; } fd = socket(domain, type, 0); if (fd == -1) { log_err("Failed to create client socket"); goto err; } if (connect(fd, (const struct sockaddr *)addr, addr_len) == -1) { log_err("Fail to connect to server"); goto err; } goto out; err: close(fd); fd = -1; out: return fd; } int init_pktinfo(int domain, struct cmsghdr *cmsg) { struct in6_pktinfo *pktinfo6; struct in_pktinfo *pktinfo4; if (domain == AF_INET) { cmsg->cmsg_level = SOL_IP; cmsg->cmsg_type = IP_PKTINFO; cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_pktinfo)); pktinfo4 = (struct in_pktinfo *)CMSG_DATA(cmsg); memset(pktinfo4, 0, sizeof(struct in_pktinfo)); if (inet_pton(domain, SRC4_IP, (void *)&pktinfo4->ipi_spec_dst) != 1) return -1; } else if (domain == AF_INET6) { cmsg->cmsg_level = SOL_IPV6; cmsg->cmsg_type = IPV6_PKTINFO; cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo)); pktinfo6 = (struct in6_pktinfo *)CMSG_DATA(cmsg); memset(pktinfo6, 0, sizeof(struct in6_pktinfo)); if (inet_pton(domain, SRC6_IP, (void *)&pktinfo6->ipi6_addr) != 1) return -1; } else { return -1; } return 0; } static int sendmsg_to_server(const struct sockaddr_storage *addr, socklen_t addr_len, int set_cmsg, int *syscall_err) { union { char buf[CMSG_SPACE(sizeof(struct in6_pktinfo))]; struct cmsghdr align; } control6; union { char buf[CMSG_SPACE(sizeof(struct in_pktinfo))]; struct cmsghdr align; } control4; struct msghdr hdr; struct iovec iov; char data = 'a'; int domain; int fd = -1; domain = addr->ss_family; if (domain != AF_INET && domain != AF_INET6) { log_err("Unsupported address family"); goto err; } fd = socket(domain, SOCK_DGRAM, 0); if (fd == -1) { log_err("Failed to create client socket"); goto err; } memset(&iov, 0, sizeof(iov)); iov.iov_base = &data; iov.iov_len = sizeof(data); memset(&hdr, 0, sizeof(hdr)); hdr.msg_name = (void *)addr; hdr.msg_namelen = addr_len; hdr.msg_iov = &iov; hdr.msg_iovlen = 1; if (set_cmsg) { if (domain == AF_INET) { hdr.msg_control = &control4; hdr.msg_controllen = sizeof(control4.buf); } else if (domain == AF_INET6) { hdr.msg_control = &control6; hdr.msg_controllen = sizeof(control6.buf); } if (init_pktinfo(domain, CMSG_FIRSTHDR(&hdr))) { log_err("Fail to init pktinfo"); goto err; } } if (sendmsg(fd, &hdr, 0) != sizeof(data)) { log_err("Fail to send message to server"); *syscall_err = errno; goto err; } goto out; err: close(fd); fd = -1; out: return fd; } static int recvmsg_from_client(int sockfd, struct sockaddr_storage *src_addr) { struct timeval tv; struct msghdr hdr; struct iovec iov; char data[64]; fd_set rfds; FD_ZERO(&rfds); FD_SET(sockfd, &rfds); tv.tv_sec = 2; tv.tv_usec = 0; if (select(sockfd + 1, &rfds, NULL, NULL, &tv) <= 0 || !FD_ISSET(sockfd, &rfds)) return -1; memset(&iov, 0, sizeof(iov)); iov.iov_base = data; iov.iov_len = sizeof(data); memset(&hdr, 0, sizeof(hdr)); hdr.msg_name = src_addr; hdr.msg_namelen = sizeof(struct sockaddr_storage); hdr.msg_iov = &iov; hdr.msg_iovlen = 1; return recvmsg(sockfd, &hdr, 0); } static int init_addrs(const struct sock_addr_test *test, struct sockaddr_storage *requested_addr, struct sockaddr_storage *expected_addr, struct sockaddr_storage *expected_src_addr) { socklen_t addr_len = sizeof(struct sockaddr_storage); if (mk_sockaddr(test->domain, test->expected_ip, test->expected_port, (struct sockaddr *)expected_addr, addr_len) == -1) goto err; if (mk_sockaddr(test->domain, test->requested_ip, test->requested_port, (struct sockaddr *)requested_addr, addr_len) == -1) goto err; if (test->expected_src_ip && mk_sockaddr(test->domain, test->expected_src_ip, 0, (struct sockaddr *)expected_src_addr, addr_len) == -1) goto err; return 0; err: return -1; } static int run_bind_test_case(const struct sock_addr_test *test) { socklen_t addr_len = sizeof(struct sockaddr_storage); struct sockaddr_storage requested_addr; struct sockaddr_storage expected_addr; int clientfd = -1; int servfd = -1; int err = 0; if (init_addrs(test, &requested_addr, &expected_addr, NULL)) goto err; servfd = start_server(test->type, &requested_addr, addr_len); if (servfd == -1) goto err; if (cmp_local_addr(servfd, &expected_addr)) goto err; /* Try to connect to server just in case */ clientfd = connect_to_server(test->type, &expected_addr, addr_len); if (clientfd == -1) goto err; goto out; err: err = -1; out: close(clientfd); close(servfd); return err; } static int run_connect_test_case(const struct sock_addr_test *test) { socklen_t addr_len = sizeof(struct sockaddr_storage); struct sockaddr_storage expected_src_addr; struct sockaddr_storage requested_addr; struct sockaddr_storage expected_addr; int clientfd = -1; int servfd = -1; int err = 0; if (init_addrs(test, &requested_addr, &expected_addr, &expected_src_addr)) goto err; /* Prepare server to connect to */ servfd = start_server(test->type, &expected_addr, addr_len); if (servfd == -1) goto err; clientfd = connect_to_server(test->type, &requested_addr, addr_len); if (clientfd == -1) goto err; /* Make sure src and dst addrs were overridden properly */ if (cmp_peer_addr(clientfd, &expected_addr)) goto err; if (cmp_local_ip(clientfd, &expected_src_addr)) goto err; goto out; err: err = -1; out: close(clientfd); close(servfd); return err; } static int run_sendmsg_test_case(const struct sock_addr_test *test) { 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; int clientfd = -1; int servfd = -1; int set_cmsg; int err = 0; if (test->type != SOCK_DGRAM) goto err; if (init_addrs(test, &requested_addr, &expected_addr, &expected_src_addr)) goto err; /* Prepare server to sendmsg to */ servfd = start_server(test->type, &expected_addr, addr_len); if (servfd == -1) goto err; for (set_cmsg = 0; set_cmsg <= 1; ++set_cmsg) { if (clientfd >= 0) close(clientfd); clientfd = sendmsg_to_server(&requested_addr, addr_len, set_cmsg, &err); if (err) goto out; else if (clientfd == -1) goto err; /* Try to receive message on server instead of using * getpeername(2) on client socket, to check that client's * destination address was rewritten properly, since * getpeername(2) doesn't work with unconnected datagram * sockets. * * Get source address from recvmsg(2) as well to make sure * source was rewritten properly: getsockname(2) can't be used * since socket is unconnected and source defined for one * specific packet may differ from the one used by default and * returned by getsockname(2). */ if (recvmsg_from_client(servfd, &real_src_addr) == -1) goto err; if (cmp_addr(&real_src_addr, &expected_src_addr, /*cmp_port*/0)) goto err; } goto out; err: err = -1; out: close(clientfd); close(servfd); return err; } static int run_test_case(int cgfd, const struct sock_addr_test *test) { int progfd = -1; int err = 0; printf("Test case: %s .. ", test->descr); progfd = test->loadfn(test); if (test->expected_result == LOAD_REJECT && progfd < 0) goto out; else if (test->expected_result == LOAD_REJECT || progfd < 0) goto err; err = bpf_prog_attach(progfd, cgfd, test->attach_type, BPF_F_ALLOW_OVERRIDE); if (test->expected_result == ATTACH_REJECT && err) { err = 0; /* error was expected, reset it */ goto out; } else if (test->expected_result == ATTACH_REJECT || err) { goto err; } switch (test->attach_type) { case BPF_CGROUP_INET4_BIND: case BPF_CGROUP_INET6_BIND: err = run_bind_test_case(test); break; case BPF_CGROUP_INET4_CONNECT: case BPF_CGROUP_INET6_CONNECT: err = run_connect_test_case(test); break; case BPF_CGROUP_UDP4_SENDMSG: case BPF_CGROUP_UDP6_SENDMSG: err = run_sendmsg_test_case(test); break; default: goto err; } if (test->expected_result == SYSCALL_EPERM && err == EPERM) { err = 0; /* error was expected, reset it */ goto out; } if (test->expected_result == SYSCALL_ENOTSUPP && err == ENOTSUPP) { err = 0; /* error was expected, reset it */ goto out; } if (err || test->expected_result != SUCCESS) goto err; goto out; err: err = -1; out: /* Detaching w/o checking return code: best effort attempt. */ if (progfd != -1) bpf_prog_detach(cgfd, test->attach_type); close(progfd); printf("[%s]\n", err ? "FAIL" : "PASS"); return err; } static int run_tests(int cgfd) { int passes = 0; int fails = 0; int i; for (i = 0; i < ARRAY_SIZE(tests); ++i) { if (run_test_case(cgfd, &tests[i])) ++fails; else ++passes; } printf("Summary: %d PASSED, %d FAILED\n", passes, fails); return fails ? -1 : 0; } int main(int argc, char **argv) { int cgfd = -1; int err = 0; if (argc < 2) { fprintf(stderr, "%s has to be run via %s.sh. Skip direct run.\n", argv[0], argv[0]); exit(err); } if (setup_cgroup_environment()) goto err; cgfd = create_and_get_cgroup(CG_PATH); if (!cgfd) goto err; if (join_cgroup(CG_PATH)) goto err; if (run_tests(cgfd)) goto err; goto out; err: err = -1; out: close(cgfd); cleanup_cgroup_environment(); return err; }