diff options
Diffstat (limited to 'tools/testing/selftests/bpf/test_sock_addr.c')
| -rw-r--r-- | tools/testing/selftests/bpf/test_sock_addr.c | 588 |
1 files changed, 588 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/test_sock_addr.c b/tools/testing/selftests/bpf/test_sock_addr.c new file mode 100644 index 000000000000..d488f20926e8 --- /dev/null +++ b/tools/testing/selftests/bpf/test_sock_addr.c @@ -0,0 +1,588 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2018 Facebook + +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> + +#include <arpa/inet.h> +#include <sys/types.h> +#include <sys/socket.h> + +#include <linux/filter.h> + +#include <bpf/bpf.h> +#include <bpf/libbpf.h> + +#include "cgroup_helpers.h" + +#define CG_PATH "/foo" +#define CONNECT4_PROG_PATH "./connect4_prog.o" +#define CONNECT6_PROG_PATH "./connect6_prog.o" + +#define SERV4_IP "192.168.1.254" +#define SERV4_REWRITE_IP "127.0.0.1" +#define SERV4_PORT 4040 +#define SERV4_REWRITE_PORT 4444 + +#define SERV6_IP "face:b00c:1234:5678::abcd" +#define SERV6_REWRITE_IP "::1" +#define SERV6_PORT 6060 +#define SERV6_REWRITE_PORT 6666 + +#define INET_NTOP_BUF 40 + +typedef int (*load_fn)(enum bpf_attach_type, const char *comment); +typedef int (*info_fn)(int, struct sockaddr *, socklen_t *); + +struct program { + enum bpf_attach_type type; + load_fn loadfn; + int fd; + const char *name; + enum bpf_attach_type invalid_type; +}; + +char bpf_log_buf[BPF_LOG_BUF_SIZE]; + +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(enum bpf_attach_type attach_type, + const struct bpf_insn *insns, size_t insns_cnt, + const char *comment) +{ + 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 = 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 && comment) { + log_err(">>> Loading %s program error.\n" + ">>> Output from verifier:\n%s\n-------\n", + comment, 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(enum bpf_attach_type attach_type, + const char *comment) +{ + 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(attach_type, insns, + sizeof(insns) / sizeof(struct bpf_insn), comment); +} + +static int bind6_prog_load(enum bpf_attach_type attach_type, + const char *comment) +{ + 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(attach_type, insns, + sizeof(insns) / sizeof(struct bpf_insn), comment); +} + +static int connect_prog_load_path(const char *path, + enum bpf_attach_type attach_type, + const char *comment) +{ + 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 = attach_type; + + if (bpf_prog_load_xattr(&attr, &obj, &prog_fd)) { + if (comment) + log_err(">>> Loading %s program at %s error.\n", + comment, path); + return -1; + } + + return prog_fd; +} + +static int connect4_prog_load(enum bpf_attach_type attach_type, + const char *comment) +{ + return connect_prog_load_path(CONNECT4_PROG_PATH, attach_type, comment); +} + +static int connect6_prog_load(enum bpf_attach_type attach_type, + const char *comment) +{ + return connect_prog_load_path(CONNECT6_PROG_PATH, attach_type, comment); +} + +static void print_ip_port(int sockfd, info_fn fn, const char *fmt) +{ + char addr_buf[INET_NTOP_BUF]; + struct sockaddr_storage addr; + struct sockaddr_in6 *addr6; + struct sockaddr_in *addr4; + socklen_t addr_len; + unsigned short port; + void *nip; + + addr_len = sizeof(struct sockaddr_storage); + memset(&addr, 0, addr_len); + + if (fn(sockfd, (struct sockaddr *)&addr, (socklen_t *)&addr_len) == 0) { + if (addr.ss_family == AF_INET) { + addr4 = (struct sockaddr_in *)&addr; + nip = (void *)&addr4->sin_addr; + port = ntohs(addr4->sin_port); + } else if (addr.ss_family == AF_INET6) { + addr6 = (struct sockaddr_in6 *)&addr; + nip = (void *)&addr6->sin6_addr; + port = ntohs(addr6->sin6_port); + } else { + return; + } + const char *addr_str = + inet_ntop(addr.ss_family, nip, addr_buf, INET_NTOP_BUF); + printf(fmt, addr_str ? addr_str : "??", port); + } +} + +static void print_local_ip_port(int sockfd, const char *fmt) +{ + print_ip_port(sockfd, getsockname, fmt); +} + +static void print_remote_ip_port(int sockfd, const char *fmt) +{ + print_ip_port(sockfd, getpeername, fmt); +} + +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; + } + } + + print_local_ip_port(fd, "\t Actual: bind(%s, %d)\n"); + + 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; + + domain = addr->ss_family; + + if (domain != AF_INET && domain != AF_INET6) { + log_err("Unsupported address family"); + return -1; + } + + fd = socket(domain, type, 0); + if (fd == -1) { + log_err("Failed to creating client socket"); + return -1; + } + + if (connect(fd, (const struct sockaddr *)addr, addr_len) == -1) { + log_err("Fail to connect to server"); + goto err; + } + + print_remote_ip_port(fd, "\t Actual: connect(%s, %d)"); + print_local_ip_port(fd, " from (%s, %d)\n"); + + return 0; +err: + close(fd); + return -1; +} + +static void print_test_case_num(int domain, int type) +{ + static int test_num; + + printf("Test case #%d (%s/%s):\n", ++test_num, + (domain == AF_INET ? "IPv4" : + domain == AF_INET6 ? "IPv6" : + "unknown_domain"), + (type == SOCK_STREAM ? "TCP" : + type == SOCK_DGRAM ? "UDP" : + "unknown_type")); +} + +static int run_test_case(int domain, int type, const char *ip, + unsigned short port) +{ + struct sockaddr_storage addr; + socklen_t addr_len = sizeof(addr); + int servfd = -1; + int err = 0; + + print_test_case_num(domain, type); + + if (mk_sockaddr(domain, ip, port, (struct sockaddr *)&addr, + addr_len) == -1) + return -1; + + printf("\tRequested: bind(%s, %d) ..\n", ip, port); + servfd = start_server(type, &addr, addr_len); + if (servfd == -1) + goto err; + + printf("\tRequested: connect(%s, %d) from (*, *) ..\n", ip, port); + if (connect_to_server(type, &addr, addr_len)) + goto err; + + goto out; +err: + err = -1; +out: + close(servfd); + return err; +} + +static void close_progs_fds(struct program *progs, size_t prog_cnt) +{ + size_t i; + + for (i = 0; i < prog_cnt; ++i) { + close(progs[i].fd); + progs[i].fd = -1; + } +} + +static int load_and_attach_progs(int cgfd, struct program *progs, + size_t prog_cnt) +{ + size_t i; + + for (i = 0; i < prog_cnt; ++i) { + printf("Load %s with invalid type (can pollute stderr) ", + progs[i].name); + fflush(stdout); + progs[i].fd = progs[i].loadfn(progs[i].invalid_type, NULL); + if (progs[i].fd != -1) { + log_err("Load with invalid type accepted for %s", + progs[i].name); + goto err; + } + printf("... REJECTED\n"); + + printf("Load %s with valid type", progs[i].name); + progs[i].fd = progs[i].loadfn(progs[i].type, progs[i].name); + if (progs[i].fd == -1) { + log_err("Failed to load program %s", progs[i].name); + goto err; + } + printf(" ... OK\n"); + + printf("Attach %s with invalid type", progs[i].name); + if (bpf_prog_attach(progs[i].fd, cgfd, progs[i].invalid_type, + BPF_F_ALLOW_OVERRIDE) != -1) { + log_err("Attach with invalid type accepted for %s", + progs[i].name); + goto err; + } + printf(" ... REJECTED\n"); + + printf("Attach %s with valid type", progs[i].name); + if (bpf_prog_attach(progs[i].fd, cgfd, progs[i].type, + BPF_F_ALLOW_OVERRIDE) == -1) { + log_err("Failed to attach program %s", progs[i].name); + goto err; + } + printf(" ... OK\n"); + } + + return 0; +err: + close_progs_fds(progs, prog_cnt); + return -1; +} + +static int run_domain_test(int domain, int cgfd, struct program *progs, + size_t prog_cnt, const char *ip, unsigned short port) +{ + int err = 0; + + if (load_and_attach_progs(cgfd, progs, prog_cnt) == -1) + goto err; + + if (run_test_case(domain, SOCK_STREAM, ip, port) == -1) + goto err; + + if (run_test_case(domain, SOCK_DGRAM, ip, port) == -1) + goto err; + + goto out; +err: + err = -1; +out: + close_progs_fds(progs, prog_cnt); + return err; +} + +static int run_test(void) +{ + size_t inet6_prog_cnt; + size_t inet_prog_cnt; + int cgfd = -1; + int err = 0; + + struct program inet6_progs[] = { + {BPF_CGROUP_INET6_BIND, bind6_prog_load, -1, "bind6", + BPF_CGROUP_INET4_BIND}, + {BPF_CGROUP_INET6_CONNECT, connect6_prog_load, -1, "connect6", + BPF_CGROUP_INET4_CONNECT}, + }; + inet6_prog_cnt = sizeof(inet6_progs) / sizeof(struct program); + + struct program inet_progs[] = { + {BPF_CGROUP_INET4_BIND, bind4_prog_load, -1, "bind4", + BPF_CGROUP_INET6_BIND}, + {BPF_CGROUP_INET4_CONNECT, connect4_prog_load, -1, "connect4", + BPF_CGROUP_INET6_CONNECT}, + }; + inet_prog_cnt = sizeof(inet_progs) / sizeof(struct program); + + 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_domain_test(AF_INET, cgfd, inet_progs, inet_prog_cnt, SERV4_IP, + SERV4_PORT) == -1) + goto err; + + if (run_domain_test(AF_INET6, cgfd, inet6_progs, inet6_prog_cnt, + SERV6_IP, SERV6_PORT) == -1) + goto err; + + goto out; +err: + err = -1; +out: + close(cgfd); + cleanup_cgroup_environment(); + printf(err ? "### FAIL\n" : "### SUCCESS\n"); + return err; +} + +int main(int argc, char **argv) +{ + if (argc < 2) { + fprintf(stderr, + "%s has to be run via %s.sh. Skip direct run.\n", + argv[0], argv[0]); + exit(0); + } + return run_test(); +} |