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7
8#define _GNU_SOURCE
9
10#include <error.h>
11#include <netinet/in.h>
12#include <netinet/tcp.h>
13#include <pthread.h>
14#include <stdio.h>
15#include <errno.h>
16#include <stdlib.h>
17#include <string.h>
18#include <sys/socket.h>
19#include <unistd.h>
20
21#ifndef TCP_INQ
22#define TCP_INQ 36
23#endif
24
25#ifndef TCP_CM_INQ
26#define TCP_CM_INQ TCP_INQ
27#endif
28
29#define BUF_SIZE 8192
30#define CMSG_SIZE 32
31
32static int family = AF_INET6;
33static socklen_t addr_len = sizeof(struct sockaddr_in6);
34static int port = 4974;
35
36static void setup_loopback_addr(int family, struct sockaddr_storage *sockaddr)
37{
38 struct sockaddr_in6 *addr6 = (void *) sockaddr;
39 struct sockaddr_in *addr4 = (void *) sockaddr;
40
41 switch (family) {
42 case PF_INET:
43 memset(addr4, 0, sizeof(*addr4));
44 addr4->sin_family = AF_INET;
45 addr4->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
46 addr4->sin_port = htons(port);
47 break;
48 case PF_INET6:
49 memset(addr6, 0, sizeof(*addr6));
50 addr6->sin6_family = AF_INET6;
51 addr6->sin6_addr = in6addr_loopback;
52 addr6->sin6_port = htons(port);
53 break;
54 default:
55 error(1, 0, "illegal family");
56 }
57}
58
59void *start_server(void *arg)
60{
61 int server_fd = (int)(unsigned long)arg;
62 struct sockaddr_in addr;
63 socklen_t addrlen = sizeof(addr);
64 char *buf;
65 int fd;
66 int r;
67
68 buf = malloc(BUF_SIZE);
69
70 for (;;) {
71 fd = accept(server_fd, (struct sockaddr *)&addr, &addrlen);
72 if (fd == -1) {
73 perror("accept");
74 break;
75 }
76 do {
77 r = send(fd, buf, BUF_SIZE, 0);
78 } while (r < 0 && errno == EINTR);
79 if (r < 0)
80 perror("send");
81 if (r != BUF_SIZE)
82 fprintf(stderr, "can only send %d bytes\n", r);
83
84
85
86
87 sleep(1);
88 close(fd);
89 }
90
91 free(buf);
92 close(server_fd);
93 pthread_exit(0);
94}
95
96int main(int argc, char *argv[])
97{
98 struct sockaddr_storage listen_addr, addr;
99 int c, one = 1, inq = -1;
100 pthread_t server_thread;
101 char cmsgbuf[CMSG_SIZE];
102 struct iovec iov[1];
103 struct cmsghdr *cm;
104 struct msghdr msg;
105 int server_fd, fd;
106 char *buf;
107
108 while ((c = getopt(argc, argv, "46p:")) != -1) {
109 switch (c) {
110 case '4':
111 family = PF_INET;
112 addr_len = sizeof(struct sockaddr_in);
113 break;
114 case '6':
115 family = PF_INET6;
116 addr_len = sizeof(struct sockaddr_in6);
117 break;
118 case 'p':
119 port = atoi(optarg);
120 break;
121 }
122 }
123
124 server_fd = socket(family, SOCK_STREAM, 0);
125 if (server_fd < 0)
126 error(1, errno, "server socket");
127 setup_loopback_addr(family, &listen_addr);
128 if (setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR,
129 &one, sizeof(one)) != 0)
130 error(1, errno, "setsockopt(SO_REUSEADDR)");
131 if (bind(server_fd, (const struct sockaddr *)&listen_addr,
132 addr_len) == -1)
133 error(1, errno, "bind");
134 if (listen(server_fd, 128) == -1)
135 error(1, errno, "listen");
136 if (pthread_create(&server_thread, NULL, start_server,
137 (void *)(unsigned long)server_fd) != 0)
138 error(1, errno, "pthread_create");
139
140 fd = socket(family, SOCK_STREAM, 0);
141 if (fd < 0)
142 error(1, errno, "client socket");
143 setup_loopback_addr(family, &addr);
144 if (connect(fd, (const struct sockaddr *)&addr, addr_len) == -1)
145 error(1, errno, "connect");
146 if (setsockopt(fd, SOL_TCP, TCP_INQ, &one, sizeof(one)) != 0)
147 error(1, errno, "setsockopt(TCP_INQ)");
148
149 msg.msg_name = NULL;
150 msg.msg_namelen = 0;
151 msg.msg_iov = iov;
152 msg.msg_iovlen = 1;
153 msg.msg_control = cmsgbuf;
154 msg.msg_controllen = sizeof(cmsgbuf);
155 msg.msg_flags = 0;
156
157 buf = malloc(BUF_SIZE);
158 iov[0].iov_base = buf;
159 iov[0].iov_len = BUF_SIZE / 2;
160
161 if (recvmsg(fd, &msg, 0) != iov[0].iov_len)
162 error(1, errno, "recvmsg");
163 if (msg.msg_flags & MSG_CTRUNC)
164 error(1, 0, "control message is truncated");
165
166 for (cm = CMSG_FIRSTHDR(&msg); cm; cm = CMSG_NXTHDR(&msg, cm))
167 if (cm->cmsg_level == SOL_TCP && cm->cmsg_type == TCP_CM_INQ)
168 inq = *((int *) CMSG_DATA(cm));
169
170 if (inq != BUF_SIZE - iov[0].iov_len) {
171 fprintf(stderr, "unexpected inq: %d\n", inq);
172 exit(1);
173 }
174
175 printf("PASSED\n");
176 free(buf);
177 close(fd);
178 return 0;
179}
180
