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
pair_udp_setfilter(int fd)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
pair_udp_open(int fds[],uint16_t port)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
pair_udp_send_char(int fds[],int num,char payload)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
pair_udp_send(int fds[],int num)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
pair_udp_close(int fds[])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 */
145