From a999696c547f1a8ef2ddbb9b0e77abc3f6db4ff1 Mon Sep 17 00:00:00 2001 From: Stanislav Fomichev Date: Wed, 2 Dec 2020 09:25:14 -0800 Subject: [PATCH] selftests/bpf: Rewrite test_sock_addr bind bpf into C I'm planning to extend it in the next patches. It's much easier to work with C than BPF assembly. Signed-off-by: Stanislav Fomichev Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20201202172516.3483656-2-sdf@google.com --- .../testing/selftests/bpf/progs/bind4_prog.c | 71 +++++++ .../testing/selftests/bpf/progs/bind6_prog.c | 88 ++++++++ tools/testing/selftests/bpf/test_sock_addr.c | 196 ++---------------- 3 files changed, 171 insertions(+), 184 deletions(-) create mode 100644 tools/testing/selftests/bpf/progs/bind4_prog.c create mode 100644 tools/testing/selftests/bpf/progs/bind6_prog.c diff --git a/tools/testing/selftests/bpf/progs/bind4_prog.c b/tools/testing/selftests/bpf/progs/bind4_prog.c new file mode 100644 index 000000000000..0951302a984a --- /dev/null +++ b/tools/testing/selftests/bpf/progs/bind4_prog.c @@ -0,0 +1,71 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include + +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#define SERV4_IP 0xc0a801feU /* 192.168.1.254 */ +#define SERV4_PORT 4040 +#define SERV4_REWRITE_IP 0x7f000001U /* 127.0.0.1 */ +#define SERV4_REWRITE_PORT 4444 + +SEC("cgroup/bind4") +int bind_v4_prog(struct bpf_sock_addr *ctx) +{ + struct bpf_sock *sk; + __u32 user_ip4; + __u16 user_port; + + sk = ctx->sk; + if (!sk) + return 0; + + if (sk->family != AF_INET) + return 0; + + if (ctx->type != SOCK_STREAM && ctx->type != SOCK_DGRAM) + return 0; + + if (ctx->user_ip4 != bpf_htonl(SERV4_IP) || + ctx->user_port != bpf_htons(SERV4_PORT)) + return 0; + + // u8 narrow loads: + user_ip4 = 0; + user_ip4 |= ((volatile __u8 *)&ctx->user_ip4)[0] << 0; + user_ip4 |= ((volatile __u8 *)&ctx->user_ip4)[1] << 8; + user_ip4 |= ((volatile __u8 *)&ctx->user_ip4)[2] << 16; + user_ip4 |= ((volatile __u8 *)&ctx->user_ip4)[3] << 24; + if (ctx->user_ip4 != user_ip4) + return 0; + + user_port = 0; + user_port |= ((volatile __u8 *)&ctx->user_port)[0] << 0; + user_port |= ((volatile __u8 *)&ctx->user_port)[1] << 8; + if (ctx->user_port != user_port) + return 0; + + // u16 narrow loads: + user_ip4 = 0; + user_ip4 |= ((volatile __u16 *)&ctx->user_ip4)[0] << 0; + user_ip4 |= ((volatile __u16 *)&ctx->user_ip4)[1] << 16; + if (ctx->user_ip4 != user_ip4) + return 0; + + ctx->user_ip4 = bpf_htonl(SERV4_REWRITE_IP); + ctx->user_port = bpf_htons(SERV4_REWRITE_PORT); + + return 1; +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/progs/bind6_prog.c b/tools/testing/selftests/bpf/progs/bind6_prog.c new file mode 100644 index 000000000000..16da1cf85418 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/bind6_prog.c @@ -0,0 +1,88 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include + +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#define SERV6_IP_0 0xfaceb00c /* face:b00c:1234:5678::abcd */ +#define SERV6_IP_1 0x12345678 +#define SERV6_IP_2 0x00000000 +#define SERV6_IP_3 0x0000abcd +#define SERV6_PORT 6060 +#define SERV6_REWRITE_IP_0 0x00000000 +#define SERV6_REWRITE_IP_1 0x00000000 +#define SERV6_REWRITE_IP_2 0x00000000 +#define SERV6_REWRITE_IP_3 0x00000001 +#define SERV6_REWRITE_PORT 6666 + +SEC("cgroup/bind6") +int bind_v6_prog(struct bpf_sock_addr *ctx) +{ + struct bpf_sock *sk; + __u32 user_ip6; + __u16 user_port; + int i; + + sk = ctx->sk; + if (!sk) + return 0; + + if (sk->family != AF_INET6) + return 0; + + if (ctx->type != SOCK_STREAM && ctx->type != SOCK_DGRAM) + return 0; + + if (ctx->user_ip6[0] != bpf_htonl(SERV6_IP_0) || + ctx->user_ip6[1] != bpf_htonl(SERV6_IP_1) || + ctx->user_ip6[2] != bpf_htonl(SERV6_IP_2) || + ctx->user_ip6[3] != bpf_htonl(SERV6_IP_3) || + ctx->user_port != bpf_htons(SERV6_PORT)) + return 0; + + // u8 narrow loads: + for (i = 0; i < 4; i++) { + user_ip6 = 0; + user_ip6 |= ((volatile __u8 *)&ctx->user_ip6[i])[0] << 0; + user_ip6 |= ((volatile __u8 *)&ctx->user_ip6[i])[1] << 8; + user_ip6 |= ((volatile __u8 *)&ctx->user_ip6[i])[2] << 16; + user_ip6 |= ((volatile __u8 *)&ctx->user_ip6[i])[3] << 24; + if (ctx->user_ip6[i] != user_ip6) + return 0; + } + + user_port = 0; + user_port |= ((volatile __u8 *)&ctx->user_port)[0] << 0; + user_port |= ((volatile __u8 *)&ctx->user_port)[1] << 8; + if (ctx->user_port != user_port) + return 0; + + // u16 narrow loads: + for (i = 0; i < 4; i++) { + user_ip6 = 0; + user_ip6 |= ((volatile __u16 *)&ctx->user_ip6[i])[0] << 0; + user_ip6 |= ((volatile __u16 *)&ctx->user_ip6[i])[1] << 16; + if (ctx->user_ip6[i] != user_ip6) + return 0; + } + + ctx->user_ip6[0] = bpf_htonl(SERV6_REWRITE_IP_0); + ctx->user_ip6[1] = bpf_htonl(SERV6_REWRITE_IP_1); + ctx->user_ip6[2] = bpf_htonl(SERV6_REWRITE_IP_2); + ctx->user_ip6[3] = bpf_htonl(SERV6_REWRITE_IP_3); + ctx->user_port = bpf_htons(SERV6_REWRITE_PORT); + + return 1; +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/test_sock_addr.c b/tools/testing/selftests/bpf/test_sock_addr.c index b8c72c1d9cf7..dcb83ab02919 100644 --- a/tools/testing/selftests/bpf/test_sock_addr.c +++ b/tools/testing/selftests/bpf/test_sock_addr.c @@ -31,6 +31,8 @@ #define CONNECT6_PROG_PATH "./connect6_prog.o" #define SENDMSG4_PROG_PATH "./sendmsg4_prog.o" #define SENDMSG6_PROG_PATH "./sendmsg6_prog.o" +#define BIND4_PROG_PATH "./bind4_prog.o" +#define BIND6_PROG_PATH "./bind6_prog.o" #define SERV4_IP "192.168.1.254" #define SERV4_REWRITE_IP "127.0.0.1" @@ -660,190 +662,6 @@ static int load_insns(const struct sock_addr_test *test, 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, port; - struct sockaddr_in addr4_rw; - - if (inet_pton(AF_INET, SERV4_IP, (void *)&ip4) != 1) { - log_err("Invalid IPv4: %s", SERV4_IP); - return -1; - } - - port.u4_addr32 = htons(SERV4_PORT); - - 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, 32), - - /* (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, 28), - - /* 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], 26), - - /* 2nd_byte_of_user_ip4 == expected && */ - BPF_LDX_MEM(BPF_B, BPF_REG_7, BPF_REG_6, - offsetof(struct bpf_sock_addr, user_ip4) + 1), - BPF_JMP_IMM(BPF_JNE, BPF_REG_7, ip4.u4_addr8[1], 24), - - /* 3rd_byte_of_user_ip4 == expected && */ - BPF_LDX_MEM(BPF_B, BPF_REG_7, BPF_REG_6, - offsetof(struct bpf_sock_addr, user_ip4) + 2), - BPF_JMP_IMM(BPF_JNE, BPF_REG_7, ip4.u4_addr8[2], 22), - - /* 4th_byte_of_user_ip4 == expected && */ - BPF_LDX_MEM(BPF_B, BPF_REG_7, BPF_REG_6, - offsetof(struct bpf_sock_addr, user_ip4) + 3), - BPF_JMP_IMM(BPF_JNE, BPF_REG_7, ip4.u4_addr8[3], 20), - - /* 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], 18), - - /* 2nd_half_of_user_ip4 == expected && */ - BPF_LDX_MEM(BPF_H, BPF_REG_7, BPF_REG_6, - offsetof(struct bpf_sock_addr, user_ip4) + 2), - BPF_JMP_IMM(BPF_JNE, BPF_REG_7, ip4.u4_addr16[1], 16), - - /* 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, 12), - - /* 1st_byte_of_user_port == expected && */ - BPF_LDX_MEM(BPF_B, BPF_REG_7, BPF_REG_6, - offsetof(struct bpf_sock_addr, user_port)), - BPF_JMP_IMM(BPF_JNE, BPF_REG_7, port.u4_addr8[0], 10), - - /* 1st_half_of_user_port == expected && */ - BPF_LDX_MEM(BPF_H, BPF_REG_7, BPF_REG_6, - offsetof(struct bpf_sock_addr, user_port)), - BPF_JMP_IMM(BPF_JNE, BPF_REG_7, port.u4_addr16[0], 8), - - /* user_port == expected) { */ - BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_6, - offsetof(struct bpf_sock_addr, user_port)), - BPF_LD_IMM64(BPF_REG_8, port.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; @@ -865,6 +683,16 @@ static int load_path(const struct sock_addr_test *test, const char *path) return prog_fd; } +static int bind4_prog_load(const struct sock_addr_test *test) +{ + return load_path(test, BIND4_PROG_PATH); +} + +static int bind6_prog_load(const struct sock_addr_test *test) +{ + return load_path(test, BIND6_PROG_PATH); +} + static int connect4_prog_load(const struct sock_addr_test *test) { return load_path(test, CONNECT4_PROG_PATH); -- 2.39.5