/* SPDX-License-Identifier: GPL-2.0-only */ /* * Copyright 2013 Google Inc. * Author: Willem de Bruijn <willemb@google.com> * Daniel Borkmann <dborkman@redhat.com> */ #ifndef PSOCK_LIB_H #define PSOCK_LIB_H #include <sys/types.h> #include <sys/socket.h> #include <string.h> #include <arpa/inet.h> #include <unistd.h> #define DATA_LEN 100 #define DATA_CHAR 'a' #define DATA_CHAR_1 'b' #define PORT_BASE 8000 #ifndef __maybe_unused # define __maybe_unused __attribute__ ((__unused__)) #endif static __maybe_unused void pair_udp_setfilter(int fd) { /* the filter below checks for all of the following conditions that * are based on the contents of create_payload() * ether type 0x800 and * ip proto udp and * skb->len == DATA_LEN and * udp[38] == 'a' or udp[38] == 'b' * It can be generated from the following bpf_asm input: * ldh [12] * jne #0x800, drop ; ETH_P_IP * ldb [23] * jneq #17, drop ; IPPROTO_UDP * ld len ; ld skb->len * jlt #100, drop ; DATA_LEN * ldb [80] * jeq #97, pass ; DATA_CHAR * jne #98, drop ; DATA_CHAR_1 * pass: * ret #-1 * drop: * ret #0 */ struct sock_filter bpf_filter[] = { { 0x28, 0, 0, 0x0000000c }, { 0x15, 0, 8, 0x00000800 }, { 0x30, 0, 0, 0x00000017 }, { 0x15, 0, 6, 0x00000011 }, { 0x80, 0, 0, 0000000000 }, { 0x35, 0, 4, 0x00000064 }, { 0x30, 0, 0, 0x00000050 }, { 0x15, 1, 0, 0x00000061 }, { 0x15, 0, 1, 0x00000062 }, { 0x06, 0, 0, 0xffffffff }, { 0x06, 0, 0, 0000000000 }, }; struct sock_fprog bpf_prog; bpf_prog.filter = bpf_filter; bpf_prog.len = sizeof(bpf_filter) / sizeof(struct sock_filter); if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &bpf_prog, sizeof(bpf_prog))) { perror("setsockopt SO_ATTACH_FILTER"); exit(1); } } static __maybe_unused void pair_udp_open(int fds[], uint16_t port) { struct sockaddr_in saddr, daddr; fds[0] = socket(PF_INET, SOCK_DGRAM, 0); fds[1] = socket(PF_INET, SOCK_DGRAM, 0); if (fds[0] == -1 || fds[1] == -1) { fprintf(stderr, "ERROR: socket dgram\n"); exit(1); } memset(&saddr, 0, sizeof(saddr)); saddr.sin_family = AF_INET; saddr.sin_port = htons(port); saddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK); memset(&daddr, 0, sizeof(daddr)); daddr.sin_family = AF_INET; daddr.sin_port = htons(port + 1); daddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK); /* must bind both to get consistent hash result */ if (bind(fds[1], (void *) &daddr, sizeof(daddr))) { perror("bind"); exit(1); } if (bind(fds[0], (void *) &saddr, sizeof(saddr))) { perror("bind"); exit(1); } if (connect(fds[0], (void *) &daddr, sizeof(daddr))) { perror("connect"); exit(1); } } static __maybe_unused void pair_udp_send_char(int fds[], int num, char payload) { char buf[DATA_LEN], rbuf[DATA_LEN]; memset(buf, payload, sizeof(buf)); while (num--) { /* Should really handle EINTR and EAGAIN */ if (write(fds[0], buf, sizeof(buf)) != sizeof(buf)) { fprintf(stderr, "ERROR: send failed left=%d\n", num); exit(1); } if (read(fds[1], rbuf, sizeof(rbuf)) != sizeof(rbuf)) { fprintf(stderr, "ERROR: recv failed left=%d\n", num); exit(1); } if (memcmp(buf, rbuf, sizeof(buf))) { fprintf(stderr, "ERROR: data failed left=%d\n", num); exit(1); } } } static __maybe_unused void pair_udp_send(int fds[], int num) { return pair_udp_send_char(fds, num, DATA_CHAR); } static __maybe_unused void pair_udp_close(int fds[]) { close(fds[0]); close(fds[1]); } #endif /* PSOCK_LIB_H */