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18#define _GNU_SOURCE
19
20#include <error.h>
21#include <netinet/in.h>
22#include <netinet/tcp.h>
23#include <pthread.h>
24#include <stdio.h>
25#include <errno.h>
26#include <stdlib.h>
27#include <string.h>
28#include <sys/socket.h>
29#include <unistd.h>
30
31#ifndef TCP_INQ
32#define TCP_INQ 36
33#endif
34
35#ifndef TCP_CM_INQ
36#define TCP_CM_INQ TCP_INQ
37#endif
38
39#define BUF_SIZE 8192
40#define CMSG_SIZE 32
41
42static int family = AF_INET6;
43static socklen_t addr_len = sizeof(struct sockaddr_in6);
44static int port = 4974;
45
46static void setup_loopback_addr(int family, struct sockaddr_storage *sockaddr)
47{
48 struct sockaddr_in6 *addr6 = (void *) sockaddr;
49 struct sockaddr_in *addr4 = (void *) sockaddr;
50
51 switch (family) {
52 case PF_INET:
53 memset(addr4, 0, sizeof(*addr4));
54 addr4->sin_family = AF_INET;
55 addr4->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
56 addr4->sin_port = htons(port);
57 break;
58 case PF_INET6:
59 memset(addr6, 0, sizeof(*addr6));
60 addr6->sin6_family = AF_INET6;
61 addr6->sin6_addr = in6addr_loopback;
62 addr6->sin6_port = htons(port);
63 break;
64 default:
65 error(1, 0, "illegal family");
66 }
67}
68
69void *start_server(void *arg)
70{
71 int server_fd = (int)(unsigned long)arg;
72 struct sockaddr_in addr;
73 socklen_t addrlen = sizeof(addr);
74 char *buf;
75 int fd;
76 int r;
77
78 buf = malloc(BUF_SIZE);
79
80 for (;;) {
81 fd = accept(server_fd, (struct sockaddr *)&addr, &addrlen);
82 if (fd == -1) {
83 perror("accept");
84 break;
85 }
86 do {
87 r = send(fd, buf, BUF_SIZE, 0);
88 } while (r < 0 && errno == EINTR);
89 if (r < 0)
90 perror("send");
91 if (r != BUF_SIZE)
92 fprintf(stderr, "can only send %d bytes\n", r);
93
94
95
96
97 sleep(1);
98 close(fd);
99 }
100
101 free(buf);
102 close(server_fd);
103 pthread_exit(0);
104}
105
106int main(int argc, char *argv[])
107{
108 struct sockaddr_storage listen_addr, addr;
109 int c, one = 1, inq = -1;
110 pthread_t server_thread;
111 char cmsgbuf[CMSG_SIZE];
112 struct iovec iov[1];
113 struct cmsghdr *cm;
114 struct msghdr msg;
115 int server_fd, fd;
116 char *buf;
117
118 while ((c = getopt(argc, argv, "46p:")) != -1) {
119 switch (c) {
120 case '4':
121 family = PF_INET;
122 addr_len = sizeof(struct sockaddr_in);
123 break;
124 case '6':
125 family = PF_INET6;
126 addr_len = sizeof(struct sockaddr_in6);
127 break;
128 case 'p':
129 port = atoi(optarg);
130 break;
131 }
132 }
133
134 server_fd = socket(family, SOCK_STREAM, 0);
135 if (server_fd < 0)
136 error(1, errno, "server socket");
137 setup_loopback_addr(family, &listen_addr);
138 if (setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR,
139 &one, sizeof(one)) != 0)
140 error(1, errno, "setsockopt(SO_REUSEADDR)");
141 if (bind(server_fd, (const struct sockaddr *)&listen_addr,
142 addr_len) == -1)
143 error(1, errno, "bind");
144 if (listen(server_fd, 128) == -1)
145 error(1, errno, "listen");
146 if (pthread_create(&server_thread, NULL, start_server,
147 (void *)(unsigned long)server_fd) != 0)
148 error(1, errno, "pthread_create");
149
150 fd = socket(family, SOCK_STREAM, 0);
151 if (fd < 0)
152 error(1, errno, "client socket");
153 setup_loopback_addr(family, &addr);
154 if (connect(fd, (const struct sockaddr *)&addr, addr_len) == -1)
155 error(1, errno, "connect");
156 if (setsockopt(fd, SOL_TCP, TCP_INQ, &one, sizeof(one)) != 0)
157 error(1, errno, "setsockopt(TCP_INQ)");
158
159 msg.msg_name = NULL;
160 msg.msg_namelen = 0;
161 msg.msg_iov = iov;
162 msg.msg_iovlen = 1;
163 msg.msg_control = cmsgbuf;
164 msg.msg_controllen = sizeof(cmsgbuf);
165 msg.msg_flags = 0;
166
167 buf = malloc(BUF_SIZE);
168 iov[0].iov_base = buf;
169 iov[0].iov_len = BUF_SIZE / 2;
170
171 if (recvmsg(fd, &msg, 0) != iov[0].iov_len)
172 error(1, errno, "recvmsg");
173 if (msg.msg_flags & MSG_CTRUNC)
174 error(1, 0, "control message is truncated");
175
176 for (cm = CMSG_FIRSTHDR(&msg); cm; cm = CMSG_NXTHDR(&msg, cm))
177 if (cm->cmsg_level == SOL_TCP && cm->cmsg_type == TCP_CM_INQ)
178 inq = *((int *) CMSG_DATA(cm));
179
180 if (inq != BUF_SIZE - iov[0].iov_len) {
181 fprintf(stderr, "unexpected inq: %d\n", inq);
182 exit(1);
183 }
184
185 printf("PASSED\n");
186 free(buf);
187 close(fd);
188 return 0;
189}
190
