b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame^] | 1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
| 2 | /* |
| 3 | * Copyright 2013 Google Inc. |
| 4 | * Author: Willem de Bruijn <willemb@google.com> |
| 5 | * Daniel Borkmann <dborkman@redhat.com> |
| 6 | */ |
| 7 | |
| 8 | #ifndef PSOCK_LIB_H |
| 9 | #define PSOCK_LIB_H |
| 10 | |
| 11 | #include <sys/types.h> |
| 12 | #include <sys/socket.h> |
| 13 | #include <string.h> |
| 14 | #include <arpa/inet.h> |
| 15 | #include <unistd.h> |
| 16 | |
| 17 | #define DATA_LEN 100 |
| 18 | #define DATA_CHAR 'a' |
| 19 | #define DATA_CHAR_1 'b' |
| 20 | |
| 21 | #define PORT_BASE 8000 |
| 22 | |
| 23 | #ifndef __maybe_unused |
| 24 | # define __maybe_unused __attribute__ ((__unused__)) |
| 25 | #endif |
| 26 | |
| 27 | static __maybe_unused void pair_udp_setfilter(int fd) |
| 28 | { |
| 29 | /* the filter below checks for all of the following conditions that |
| 30 | * are based on the contents of create_payload() |
| 31 | * ether type 0x800 and |
| 32 | * ip proto udp and |
| 33 | * skb->len == DATA_LEN and |
| 34 | * udp[38] == 'a' or udp[38] == 'b' |
| 35 | * It can be generated from the following bpf_asm input: |
| 36 | * ldh [12] |
| 37 | * jne #0x800, drop ; ETH_P_IP |
| 38 | * ldb [23] |
| 39 | * jneq #17, drop ; IPPROTO_UDP |
| 40 | * ld len ; ld skb->len |
| 41 | * jlt #100, drop ; DATA_LEN |
| 42 | * ldb [80] |
| 43 | * jeq #97, pass ; DATA_CHAR |
| 44 | * jne #98, drop ; DATA_CHAR_1 |
| 45 | * pass: |
| 46 | * ret #-1 |
| 47 | * drop: |
| 48 | * ret #0 |
| 49 | */ |
| 50 | struct sock_filter bpf_filter[] = { |
| 51 | { 0x28, 0, 0, 0x0000000c }, |
| 52 | { 0x15, 0, 8, 0x00000800 }, |
| 53 | { 0x30, 0, 0, 0x00000017 }, |
| 54 | { 0x15, 0, 6, 0x00000011 }, |
| 55 | { 0x80, 0, 0, 0000000000 }, |
| 56 | { 0x35, 0, 4, 0x00000064 }, |
| 57 | { 0x30, 0, 0, 0x00000050 }, |
| 58 | { 0x15, 1, 0, 0x00000061 }, |
| 59 | { 0x15, 0, 1, 0x00000062 }, |
| 60 | { 0x06, 0, 0, 0xffffffff }, |
| 61 | { 0x06, 0, 0, 0000000000 }, |
| 62 | }; |
| 63 | struct sock_fprog bpf_prog; |
| 64 | |
| 65 | bpf_prog.filter = bpf_filter; |
| 66 | bpf_prog.len = sizeof(bpf_filter) / sizeof(struct sock_filter); |
| 67 | |
| 68 | if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &bpf_prog, |
| 69 | sizeof(bpf_prog))) { |
| 70 | perror("setsockopt SO_ATTACH_FILTER"); |
| 71 | exit(1); |
| 72 | } |
| 73 | } |
| 74 | |
| 75 | static __maybe_unused void pair_udp_open(int fds[], uint16_t port) |
| 76 | { |
| 77 | struct sockaddr_in saddr, daddr; |
| 78 | |
| 79 | fds[0] = socket(PF_INET, SOCK_DGRAM, 0); |
| 80 | fds[1] = socket(PF_INET, SOCK_DGRAM, 0); |
| 81 | if (fds[0] == -1 || fds[1] == -1) { |
| 82 | fprintf(stderr, "ERROR: socket dgram\n"); |
| 83 | exit(1); |
| 84 | } |
| 85 | |
| 86 | memset(&saddr, 0, sizeof(saddr)); |
| 87 | saddr.sin_family = AF_INET; |
| 88 | saddr.sin_port = htons(port); |
| 89 | saddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK); |
| 90 | |
| 91 | memset(&daddr, 0, sizeof(daddr)); |
| 92 | daddr.sin_family = AF_INET; |
| 93 | daddr.sin_port = htons(port + 1); |
| 94 | daddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK); |
| 95 | |
| 96 | /* must bind both to get consistent hash result */ |
| 97 | if (bind(fds[1], (void *) &daddr, sizeof(daddr))) { |
| 98 | perror("bind"); |
| 99 | exit(1); |
| 100 | } |
| 101 | if (bind(fds[0], (void *) &saddr, sizeof(saddr))) { |
| 102 | perror("bind"); |
| 103 | exit(1); |
| 104 | } |
| 105 | if (connect(fds[0], (void *) &daddr, sizeof(daddr))) { |
| 106 | perror("connect"); |
| 107 | exit(1); |
| 108 | } |
| 109 | } |
| 110 | |
| 111 | static __maybe_unused void pair_udp_send_char(int fds[], int num, char payload) |
| 112 | { |
| 113 | char buf[DATA_LEN], rbuf[DATA_LEN]; |
| 114 | |
| 115 | memset(buf, payload, sizeof(buf)); |
| 116 | while (num--) { |
| 117 | /* Should really handle EINTR and EAGAIN */ |
| 118 | if (write(fds[0], buf, sizeof(buf)) != sizeof(buf)) { |
| 119 | fprintf(stderr, "ERROR: send failed left=%d\n", num); |
| 120 | exit(1); |
| 121 | } |
| 122 | if (read(fds[1], rbuf, sizeof(rbuf)) != sizeof(rbuf)) { |
| 123 | fprintf(stderr, "ERROR: recv failed left=%d\n", num); |
| 124 | exit(1); |
| 125 | } |
| 126 | if (memcmp(buf, rbuf, sizeof(buf))) { |
| 127 | fprintf(stderr, "ERROR: data failed left=%d\n", num); |
| 128 | exit(1); |
| 129 | } |
| 130 | } |
| 131 | } |
| 132 | |
| 133 | static __maybe_unused void pair_udp_send(int fds[], int num) |
| 134 | { |
| 135 | return pair_udp_send_char(fds, num, DATA_CHAR); |
| 136 | } |
| 137 | |
| 138 | static __maybe_unused void pair_udp_close(int fds[]) |
| 139 | { |
| 140 | close(fds[0]); |
| 141 | close(fds[1]); |
| 142 | } |
| 143 | |
| 144 | #endif /* PSOCK_LIB_H */ |