1 /*-
2  * Copyright (c) 2003-2005 MAEKAWA Masahide <maekawa@cvsync.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the author nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/types.h>
31 #include <sys/socket.h>
32 
33 #include <netdb.h>
34 #include <netinet/in.h>
35 #include <arpa/inet.h>
36 
37 #include <stdlib.h>
38 
39 #include <errno.h>
40 #include <fcntl.h>
41 #include <limits.h>
42 #include <string.h>
43 #include <unistd.h>
44 
45 #include "compat_stdbool.h"
46 
47 #include "logmsg.h"
48 #include "network.h"
49 
50 int ipv4_listen_addr(in_addr_t, in_port_t);
51 int ipv4_connect_addr(in_addr_t, in_port_t);
52 in_port_t ipv4_port_pton(const char *);
53 
54 int *
sock_listen(const char * host,const char * serv)55 sock_listen(const char *host, const char *serv)
56 {
57 	struct hostent *h;
58 	struct in_addr in;
59 	in_addr_t addr;
60 	in_port_t port;
61 	int *socks, sock, nsocks, i;
62 
63 	if (serv == NULL)
64 		return (NULL);
65 	if ((port = ipv4_port_pton(serv)) == 0)
66 		return (NULL);
67 
68 	if (host == NULL) {
69 		if ((socks = malloc(2 * sizeof(*socks))) == NULL) {
70 			logmsg_err("%s", strerror(errno));
71 			return (NULL);
72 		}
73 		addr = htonl(INADDR_ANY);
74 		if ((socks[0] = ipv4_listen_addr(addr, port)) == -1) {
75 			free(socks);
76 			return (NULL);
77 		}
78 
79 		in.s_addr = addr;
80 		logmsg_verbose("Listen on %s port %u", inet_ntoa(in), port);
81 
82 		socks[1] = -1;
83 		return (socks);
84 	}
85 	if ((addr = inet_addr(host)) != (in_addr_t)-1) {
86 		if ((socks = malloc(2 * sizeof(*socks))) == NULL) {
87 			logmsg_err("%s", strerror(errno));
88 			return (NULL);
89 		}
90 		if ((socks[0] = ipv4_listen_addr(addr, port)) == -1) {
91 			free(socks);
92 			return (NULL);
93 		}
94 		socks[1] = -1;
95 		return (socks);
96 	}
97 
98 	if ((h = gethostbyname(host)) == NULL)
99 		return (NULL);
100 
101 	for (nsocks = 0 ; h->h_addr_list[nsocks] != NULL ; nsocks++)
102 		/* Nothing to do. */;
103 	if (nsocks == 0) {
104 		logmsg_err("no address available");
105 		return (NULL);
106 	}
107 
108 	if ((socks = malloc((nsocks + 1) * sizeof(*socks))) == NULL) {
109 		logmsg_err("%s", strerror(errno));
110 		return (NULL);
111 	}
112 
113 	nsocks = 0;
114 	for (i = 0 ; h->h_addr_list[i] != NULL ; i++) {
115 		addr = *(in_addr_t *)(void *)h->h_addr_list[i];
116 		if ((sock = ipv4_listen_addr(addr, port)) == -1)
117 			continue;
118 
119 		in.s_addr = addr;
120 		logmsg_verbose("Listen on %s port %u", inet_ntoa(in), port);
121 
122 		socks[nsocks++] = sock;
123 	}
124 
125 	if (nsocks == 0) {
126 		logmsg_err("no listening socket");
127 		free(socks);
128 		return (NULL);
129 	}
130 
131 	socks[nsocks] = -1;
132 
133 	return (socks);
134 }
135 
136 int
sock_connect(int af,const char * host,const char * serv)137 sock_connect(int af, const char *host, const char *serv)
138 {
139 	struct hostent *h;
140 	struct in_addr in;
141 	in_addr_t addr;
142 	in_port_t port;
143 	int sock = -1, i;
144 
145 	if ((af != AF_UNSPEC) && (af != AF_INET))
146 		return (-1);
147 	if ((host == NULL) || (serv == NULL))
148 		return (-1);
149 
150 	logmsg("Connecting to %s port %s", host, serv);
151 
152 	if ((port = ipv4_port_pton(serv)) == 0)
153 		return (-1);
154 
155 	if ((addr = inet_addr(host)) != (in_addr_t)-1) {
156 		if ((sock = ipv4_connect_addr(addr, port)) == -1)
157 			return (-1);
158 		goto done;
159 	}
160 
161 	if ((h = gethostbyname(host)) == NULL)
162 		return (-1);
163 
164 	for (i = 0 ; h->h_addr_list[i] != NULL ; i++) {
165 		addr = *(in_addr_t *)(void *)h->h_addr_list[i];
166 		if ((sock = ipv4_connect_addr(addr, port)) == -1)
167 			continue;
168 
169 		break;
170 	}
171 
172 	if (sock == -1)
173 		return (-1);
174 
175 done:
176 	in.s_addr = addr; /* already network byte order */
177 	logmsg("Connected to %s port %u", inet_ntoa(in), port);
178 
179 	return (sock);
180 }
181 
182 bool
sock_getpeeraddr(int sock,int * af,void * buffer,size_t bufsize)183 sock_getpeeraddr(int sock, int *af, void *buffer, size_t bufsize)
184 {
185 	struct sockaddr_in sin4;
186 	char *cp;
187 	socklen_t sin4len = sizeof(sin4);
188 	size_t len;
189 
190 	*af = AF_INET;
191 
192 	if (getpeername(sock, (struct sockaddr *)(void *)&sin4,
193 			&sin4len) == -1) {
194 		logmsg_err("%s", strerror(errno));
195 		return (false);
196 	}
197 
198 	if ((cp = inet_ntoa(sin4.sin_addr)) == NULL)
199 		return (false);
200 	if ((len = strlen(cp)) >= bufsize)
201 		return (false);
202 	(void)memcpy(buffer, cp, len);
203 	((char *)buffer)[len] = '\0';
204 
205 	return (true);
206 }
207 
208 void
sock_resolv_addr(int af,const char * addr,char * buffer,size_t bufsize)209 sock_resolv_addr(int af, const char *addr, char *buffer, size_t bufsize)
210 {
211 	struct hostent *h;
212 	size_t len;
213 
214 	buffer[0] = '\0';
215 
216 	if (af != AF_INET)
217 		return;
218 
219 	if ((h = gethostbyname(addr)) == NULL)
220 		return;
221 
222 	if ((h->h_name == NULL) || ((len = strlen(h->h_name)) >= bufsize))
223 		return;
224 
225 	(void)memcpy(buffer, h->h_name, len);
226 	buffer[len] = '\0';
227 }
228 
229 int
ipv4_listen_addr(in_addr_t addr,in_port_t port)230 ipv4_listen_addr(in_addr_t addr, in_port_t port)
231 {
232 	static const int on = 1;
233 	struct sockaddr_in sin4;
234 	int sock, flags;
235 
236 	if ((sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) == -1)
237 		return (-1);
238 
239 	if ((flags = fcntl(sock, F_GETFL)) < 0) {
240 		(void)close(sock);
241 		return (-1);
242 	}
243 	if (fcntl(sock, F_SETFL, flags | O_NONBLOCK) == -1) {
244 		(void)close(sock);
245 		return (-1);
246 	}
247 
248 	if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &on,
249 		       sizeof(on)) == -1) {
250 		(void)close(sock);
251 		return (-1);
252 	}
253 
254 	sin4.sin_family = AF_INET;
255 	sin4.sin_port = htons(port);
256 	sin4.sin_addr.s_addr = addr; /* already network byte order */
257 
258 	if (bind(sock, (struct sockaddr *)(void *)&sin4,
259 		 sizeof(sin4)) == -1) {
260 		(void)close(sock);
261 		return (-1);
262 	}
263 
264 	if (listen(sock, SOMAXCONN) == -1) {
265 		(void)close(sock);
266 		return (-1);
267 	}
268 
269 	return (sock);
270 }
271 
272 int
ipv4_connect_addr(in_addr_t addr,in_port_t port)273 ipv4_connect_addr(in_addr_t addr, in_port_t port)
274 {
275 	struct sockaddr_in sin4;
276 	int sock;
277 
278 	if ((sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) == -1)
279 		return (-1);
280 
281 	sin4.sin_family = AF_INET;
282 	sin4.sin_port = htons(port);
283 	sin4.sin_addr.s_addr = addr; /* already network byte order */
284 
285 	if (connect(sock, (struct sockaddr *)(void *)&sin4,
286 		    sizeof(sin4)) == -1) {
287 		(void)close(sock);
288 		return (-1);
289 	}
290 
291 	return (sock);
292 }
293 
294 in_port_t
ipv4_port_pton(const char * name)295 ipv4_port_pton(const char *name)
296 {
297 	struct servent *serv;
298 	char *ep;
299 	unsigned long ul;
300 
301 	if ((serv = getservbyname(name, "tcp")) != NULL)
302 		return (ntohs(serv->s_port));
303 
304 	errno = 0;
305 	ul = strtoul(name, &ep, 10);
306 	if ((ep == NULL) || (*ep != '\0') ||
307 	    ((ul == 0) && (errno == EINVAL)) ||
308 	    ((ul == ULONG_MAX) && (errno == ERANGE))) {
309 		return (0);
310 	}
311 	if ((ul == 0) || (ul > 65535))
312 		return (0);
313 
314 	return ((in_port_t)ul);
315 }
316