Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2#include <error.h>
3#include <fcntl.h>
4#include <limits.h>
5#include <stdbool.h>
6#include <stdint.h>
7#include <stdio.h>
8#include <stdlib.h>
9#include <string.h>
10#include <unistd.h>
11#include <arpa/inet.h>
12#include <sys/socket.h>
13#include <netinet/tcp.h>
14#include <errno.h>
15
16static int cfg_server;
17static int cfg_client;
18static int cfg_port = 8000;
19static struct sockaddr_in6 cfg_addr;
20static char *cfg_outfile;
21
22static int parse_address(const char *str, int port, struct sockaddr_in6 *sin6)
23{
24 int ret;
25
26 sin6->sin6_family = AF_INET6;
27 sin6->sin6_port = htons(port);
28
29 ret = inet_pton(sin6->sin6_family, str, &sin6->sin6_addr);
30 if (ret != 1) {
31 /* fallback to plain IPv4 */
32 ret = inet_pton(AF_INET, str, &sin6->sin6_addr.s6_addr32[3]);
33 if (ret != 1)
34 return -1;
35
36 /* add ::ffff prefix */
37 sin6->sin6_addr.s6_addr32[0] = 0;
38 sin6->sin6_addr.s6_addr32[1] = 0;
39 sin6->sin6_addr.s6_addr16[4] = 0;
40 sin6->sin6_addr.s6_addr16[5] = 0xffff;
41 }
42
43 return 0;
44}
45
46static void run_server(void)
47{
48 unsigned long qlen = 32;
49 int fd, opt, connfd;
50 socklen_t len;
51 char buf[64];
52 FILE *outfile;
53
54 outfile = fopen(cfg_outfile, "w");
55 if (!outfile)
56 error(1, errno, "fopen() outfile");
57
58 fd = socket(AF_INET6, SOCK_STREAM, 0);
59 if (fd == -1)
60 error(1, errno, "socket()");
61
62 opt = 1;
63 if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt)) < 0)
64 error(1, errno, "setsockopt(SO_REUSEADDR)");
65
66 if (setsockopt(fd, SOL_TCP, TCP_FASTOPEN, &qlen, sizeof(qlen)) < 0)
67 error(1, errno, "setsockopt(TCP_FASTOPEN)");
68
69 if (bind(fd, (struct sockaddr *)&cfg_addr, sizeof(cfg_addr)) < 0)
70 error(1, errno, "bind()");
71
72 if (listen(fd, 5) < 0)
73 error(1, errno, "listen()");
74
75 len = sizeof(cfg_addr);
76 connfd = accept(fd, (struct sockaddr *)&cfg_addr, &len);
77 if (connfd < 0)
78 error(1, errno, "accept()");
79
80 len = sizeof(opt);
81 if (getsockopt(connfd, SOL_SOCKET, SO_INCOMING_NAPI_ID, &opt, &len) < 0)
82 error(1, errno, "getsockopt(SO_INCOMING_NAPI_ID)");
83
84 if (read(connfd, buf, 64) < 0)
85 error(1, errno, "read()");
86
87 if (fprintf(outfile, "%d\n", opt) < 0)
88 error(1, errno, "fprintf()");
89
90 fclose(outfile);
91 close(connfd);
92 close(fd);
93}
94
95static void run_client(void)
96{
97 int fd, ret;
98 char *msg = "Hello, world!";
99
100 fd = socket(AF_INET6, SOCK_STREAM, 0);
101 if (fd == -1)
102 error(1, errno, "socket()");
103
104 ret = sendto(fd, msg, strlen(msg), MSG_FASTOPEN,
105 (struct sockaddr *)&cfg_addr, sizeof(cfg_addr));
106 if (ret < 0)
107 error(1, errno, "sendto()");
108
109 close(fd);
110}
111
112static void usage(const char *filepath)
113{
114 error(1, 0, "Usage: %s (-s|-c) -h<server_ip> -p<port> -o<outfile> ", filepath);
115}
116
117static void parse_opts(int argc, char **argv)
118{
119 struct sockaddr_in6 *addr6 = (void *) &cfg_addr;
120 char *addr = NULL;
121 int ret;
122 int c;
123
124 if (argc <= 1)
125 usage(argv[0]);
126
127 while ((c = getopt(argc, argv, "sch:p:o:")) != -1) {
128 switch (c) {
129 case 's':
130 if (cfg_client)
131 error(1, 0, "Pass one of -s or -c");
132 cfg_server = 1;
133 break;
134 case 'c':
135 if (cfg_server)
136 error(1, 0, "Pass one of -s or -c");
137 cfg_client = 1;
138 break;
139 case 'h':
140 addr = optarg;
141 break;
142 case 'p':
143 cfg_port = strtoul(optarg, NULL, 0);
144 break;
145 case 'o':
146 cfg_outfile = strdup(optarg);
147 if (!cfg_outfile)
148 error(1, 0, "outfile invalid");
149 break;
150 }
151 }
152
153 if (cfg_server && addr)
154 error(1, 0, "Server cannot have -h specified");
155
156 memset(addr6, 0, sizeof(*addr6));
157 addr6->sin6_family = AF_INET6;
158 addr6->sin6_port = htons(cfg_port);
159 addr6->sin6_addr = in6addr_any;
160 if (addr) {
161 ret = parse_address(addr, cfg_port, addr6);
162 if (ret)
163 error(1, 0, "Client address parse error: %s", addr);
164 }
165}
166
167int main(int argc, char **argv)
168{
169 parse_opts(argc, argv);
170
171 if (cfg_server)
172 run_server();
173 else if (cfg_client)
174 run_client();
175
176 return 0;
177}