1 /*
2  * Copyright 2013 Google Inc.
3  * Author: Willem de Bruijn <willemb@google.com>
4  *         Daniel Borkmann <dborkman@redhat.com>
5  *
6  * License (GPLv2):
7  *
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms and conditions of the GNU General Public License,
10  * version 2, as published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope it will be useful, but WITHOUT
13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14  * FITNESS FOR A PARTICULAR PURPOSE. * See the GNU General Public License for
15  * more details.
16  *
17  * You should have received a copy of the GNU General Public License along with
18  * this program; if not, write to the Free Software Foundation, Inc.,
19  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
20  */
21 
22 #ifndef PSOCK_LIB_H
23 #define PSOCK_LIB_H
24 
25 #include <sys/types.h>
26 #include <sys/socket.h>
27 #include <string.h>
28 #include <arpa/inet.h>
29 #include <unistd.h>
30 
31 #define DATA_LEN			100
32 #define DATA_CHAR			'a'
33 #define DATA_CHAR_1			'b'
34 
35 #define PORT_BASE			8000
36 
37 #ifndef __maybe_unused
38 # define __maybe_unused		__attribute__ ((__unused__))
39 #endif
40 
41 static __maybe_unused void sock_setfilter(int fd, int lvl, int optnum)
42 {
43 	struct sock_filter bpf_filter[] = {
44 		{ 0x80, 0, 0, 0x00000000 },  /* LD  pktlen		      */
45 		{ 0x35, 0, 4, DATA_LEN   },  /* JGE DATA_LEN  [f goto nomatch]*/
46 		{ 0x30, 0, 0, 0x00000050 },  /* LD  ip[80]		      */
47 		{ 0x15, 1, 0, DATA_CHAR  },  /* JEQ DATA_CHAR   [t goto match]*/
48 		{ 0x15, 0, 1, DATA_CHAR_1},  /* JEQ DATA_CHAR_1 [t goto match]*/
49 		{ 0x06, 0, 0, 0x00000060 },  /* RET match	              */
50 		{ 0x06, 0, 0, 0x00000000 },  /* RET no match		      */
51 	};
52 	struct sock_fprog bpf_prog;
53 
54 	if (lvl == SOL_PACKET && optnum == PACKET_FANOUT_DATA)
55 		bpf_filter[5].code = 0x16;   /* RET A			      */
56 
57 	bpf_prog.filter = bpf_filter;
58 	bpf_prog.len = sizeof(bpf_filter) / sizeof(struct sock_filter);
59 	if (setsockopt(fd, lvl, optnum, &bpf_prog,
60 		       sizeof(bpf_prog))) {
61 		perror("setsockopt SO_ATTACH_FILTER");
62 		exit(1);
63 	}
64 }
65 
66 static __maybe_unused void pair_udp_setfilter(int fd)
67 {
68 	sock_setfilter(fd, SOL_SOCKET, SO_ATTACH_FILTER);
69 }
70 
71 static __maybe_unused void pair_udp_open(int fds[], uint16_t port)
72 {
73 	struct sockaddr_in saddr, daddr;
74 
75 	fds[0] = socket(PF_INET, SOCK_DGRAM, 0);
76 	fds[1] = socket(PF_INET, SOCK_DGRAM, 0);
77 	if (fds[0] == -1 || fds[1] == -1) {
78 		fprintf(stderr, "ERROR: socket dgram\n");
79 		exit(1);
80 	}
81 
82 	memset(&saddr, 0, sizeof(saddr));
83 	saddr.sin_family = AF_INET;
84 	saddr.sin_port = htons(port);
85 	saddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
86 
87 	memset(&daddr, 0, sizeof(daddr));
88 	daddr.sin_family = AF_INET;
89 	daddr.sin_port = htons(port + 1);
90 	daddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
91 
92 	/* must bind both to get consistent hash result */
93 	if (bind(fds[1], (void *) &daddr, sizeof(daddr))) {
94 		perror("bind");
95 		exit(1);
96 	}
97 	if (bind(fds[0], (void *) &saddr, sizeof(saddr))) {
98 		perror("bind");
99 		exit(1);
100 	}
101 	if (connect(fds[0], (void *) &daddr, sizeof(daddr))) {
102 		perror("connect");
103 		exit(1);
104 	}
105 }
106 
107 static __maybe_unused void pair_udp_send_char(int fds[], int num, char payload)
108 {
109 	char buf[DATA_LEN], rbuf[DATA_LEN];
110 
111 	memset(buf, payload, sizeof(buf));
112 	while (num--) {
113 		/* Should really handle EINTR and EAGAIN */
114 		if (write(fds[0], buf, sizeof(buf)) != sizeof(buf)) {
115 			fprintf(stderr, "ERROR: send failed left=%d\n", num);
116 			exit(1);
117 		}
118 		if (read(fds[1], rbuf, sizeof(rbuf)) != sizeof(rbuf)) {
119 			fprintf(stderr, "ERROR: recv failed left=%d\n", num);
120 			exit(1);
121 		}
122 		if (memcmp(buf, rbuf, sizeof(buf))) {
123 			fprintf(stderr, "ERROR: data failed left=%d\n", num);
124 			exit(1);
125 		}
126 	}
127 }
128 
129 static __maybe_unused void pair_udp_send(int fds[], int num)
130 {
131 	return pair_udp_send_char(fds, num, DATA_CHAR);
132 }
133 
134 static __maybe_unused void pair_udp_close(int fds[])
135 {
136 	close(fds[0]);
137 	close(fds[1]);
138 }
139 
140 #endif /* PSOCK_LIB_H */
141