1 /*
2 * Copyright 2016-2021 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 #include <stdio.h>
11 #include <stdlib.h>
12 #include <errno.h>
13
14 #include "bio_local.h"
15
16 #include <openssl/err.h>
17
18 #ifndef OPENSSL_NO_SOCK
19 # ifdef SO_MAXCONN
20 # define MAX_LISTEN SO_MAXCONN
21 # elif defined(SOMAXCONN)
22 # define MAX_LISTEN SOMAXCONN
23 # else
24 # define MAX_LISTEN 32
25 # endif
26
27 /*-
28 * BIO_socket - create a socket
29 * @domain: the socket domain (AF_INET, AF_INET6, AF_UNIX, ...)
30 * @socktype: the socket type (SOCK_STEAM, SOCK_DGRAM)
31 * @protocol: the protocol to use (IPPROTO_TCP, IPPROTO_UDP)
32 * @options: BIO socket options (currently unused)
33 *
34 * Creates a socket. This should be called before calling any
35 * of BIO_connect and BIO_listen.
36 *
37 * Returns the file descriptor on success or INVALID_SOCKET on failure. On
38 * failure errno is set, and a status is added to the OpenSSL error stack.
39 */
BIO_socket(int domain,int socktype,int protocol,int options)40 int BIO_socket(int domain, int socktype, int protocol, int options)
41 {
42 int sock = -1;
43
44 if (BIO_sock_init() != 1)
45 return INVALID_SOCKET;
46
47 sock = socket(domain, socktype, protocol);
48 if (sock == -1) {
49 SYSerr(SYS_F_SOCKET, get_last_socket_error());
50 BIOerr(BIO_F_BIO_SOCKET, BIO_R_UNABLE_TO_CREATE_SOCKET);
51 return INVALID_SOCKET;
52 }
53
54 return sock;
55 }
56
57 /*-
58 * BIO_connect - connect to an address
59 * @sock: the socket to connect with
60 * @addr: the address to connect to
61 * @options: BIO socket options
62 *
63 * Connects to the address using the given socket and options.
64 *
65 * Options can be a combination of the following:
66 * - BIO_SOCK_KEEPALIVE: enable regularly sending keep-alive messages.
67 * - BIO_SOCK_NONBLOCK: Make the socket non-blocking.
68 * - BIO_SOCK_NODELAY: don't delay small messages.
69 *
70 * options holds BIO socket options that can be used
71 * You should call this for every address returned by BIO_lookup
72 * until the connection is successful.
73 *
74 * Returns 1 on success or 0 on failure. On failure errno is set
75 * and an error status is added to the OpenSSL error stack.
76 */
BIO_connect(int sock,const BIO_ADDR * addr,int options)77 int BIO_connect(int sock, const BIO_ADDR *addr, int options)
78 {
79 const int on = 1;
80
81 if (sock == -1) {
82 BIOerr(BIO_F_BIO_CONNECT, BIO_R_INVALID_SOCKET);
83 return 0;
84 }
85
86 if (!BIO_socket_nbio(sock, (options & BIO_SOCK_NONBLOCK) != 0))
87 return 0;
88
89 if (options & BIO_SOCK_KEEPALIVE) {
90 if (setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
91 (const void *)&on, sizeof(on)) != 0) {
92 SYSerr(SYS_F_SETSOCKOPT, get_last_socket_error());
93 BIOerr(BIO_F_BIO_CONNECT, BIO_R_UNABLE_TO_KEEPALIVE);
94 return 0;
95 }
96 }
97
98 if (options & BIO_SOCK_NODELAY) {
99 if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY,
100 (const void *)&on, sizeof(on)) != 0) {
101 SYSerr(SYS_F_SETSOCKOPT, get_last_socket_error());
102 BIOerr(BIO_F_BIO_CONNECT, BIO_R_UNABLE_TO_NODELAY);
103 return 0;
104 }
105 }
106
107 if (connect(sock, BIO_ADDR_sockaddr(addr),
108 BIO_ADDR_sockaddr_size(addr)) == -1) {
109 if (!BIO_sock_should_retry(-1)) {
110 SYSerr(SYS_F_CONNECT, get_last_socket_error());
111 BIOerr(BIO_F_BIO_CONNECT, BIO_R_CONNECT_ERROR);
112 }
113 return 0;
114 }
115 return 1;
116 }
117
118 /*-
119 * BIO_bind - bind socket to address
120 * @sock: the socket to set
121 * @addr: local address to bind to
122 * @options: BIO socket options
123 *
124 * Binds to the address using the given socket and options.
125 *
126 * Options can be a combination of the following:
127 * - BIO_SOCK_REUSEADDR: Try to reuse the address and port combination
128 * for a recently closed port.
129 *
130 * When restarting the program it could be that the port is still in use. If
131 * you set to BIO_SOCK_REUSEADDR option it will try to reuse the port anyway.
132 * It's recommended that you use this.
133 */
BIO_bind(int sock,const BIO_ADDR * addr,int options)134 int BIO_bind(int sock, const BIO_ADDR *addr, int options)
135 {
136 # ifndef OPENSSL_SYS_WINDOWS
137 int on = 1;
138 # endif
139
140 if (sock == -1) {
141 BIOerr(BIO_F_BIO_BIND, BIO_R_INVALID_SOCKET);
142 return 0;
143 }
144
145 # ifndef OPENSSL_SYS_WINDOWS
146 /*
147 * SO_REUSEADDR has different behavior on Windows than on
148 * other operating systems, don't set it there.
149 */
150 if (options & BIO_SOCK_REUSEADDR) {
151 if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
152 (const void *)&on, sizeof(on)) != 0) {
153 SYSerr(SYS_F_SETSOCKOPT, get_last_socket_error());
154 BIOerr(BIO_F_BIO_BIND, BIO_R_UNABLE_TO_REUSEADDR);
155 return 0;
156 }
157 }
158 # endif
159
160 if (bind(sock, BIO_ADDR_sockaddr(addr), BIO_ADDR_sockaddr_size(addr)) != 0) {
161 SYSerr(SYS_F_BIND, get_last_socket_error());
162 BIOerr(BIO_F_BIO_BIND, BIO_R_UNABLE_TO_BIND_SOCKET);
163 return 0;
164 }
165
166 return 1;
167 }
168
169 /*-
170 * BIO_listen - Creates a listen socket
171 * @sock: the socket to listen with
172 * @addr: local address to bind to
173 * @options: BIO socket options
174 *
175 * Binds to the address using the given socket and options, then
176 * starts listening for incoming connections.
177 *
178 * Options can be a combination of the following:
179 * - BIO_SOCK_KEEPALIVE: enable regularly sending keep-alive messages.
180 * - BIO_SOCK_NONBLOCK: Make the socket non-blocking.
181 * - BIO_SOCK_NODELAY: don't delay small messages.
182 * - BIO_SOCK_REUSEADDR: Try to reuse the address and port combination
183 * for a recently closed port.
184 * - BIO_SOCK_V6_ONLY: When creating an IPv6 socket, make it listen only
185 * for IPv6 addresses and not IPv4 addresses mapped to IPv6.
186 *
187 * It's recommended that you set up both an IPv6 and IPv4 listen socket, and
188 * then check both for new clients that connect to it. You want to set up
189 * the socket as non-blocking in that case since else it could hang.
190 *
191 * Not all operating systems support IPv4 addresses on an IPv6 socket, and for
192 * others it's an option. If you pass the BIO_LISTEN_V6_ONLY it will try to
193 * create the IPv6 sockets to only listen for IPv6 connection.
194 *
195 * It could be that the first BIO_listen() call will listen to all the IPv6
196 * and IPv4 addresses and that then trying to bind to the IPv4 address will
197 * fail. We can't tell the difference between already listening ourself to
198 * it and someone else listening to it when failing and errno is EADDRINUSE, so
199 * it's recommended to not give an error in that case if the first call was
200 * successful.
201 *
202 * When restarting the program it could be that the port is still in use. If
203 * you set to BIO_SOCK_REUSEADDR option it will try to reuse the port anyway.
204 * It's recommended that you use this.
205 */
BIO_listen(int sock,const BIO_ADDR * addr,int options)206 int BIO_listen(int sock, const BIO_ADDR *addr, int options)
207 {
208 int on = 1;
209 int socktype;
210 socklen_t socktype_len = sizeof(socktype);
211
212 if (sock == -1) {
213 BIOerr(BIO_F_BIO_LISTEN, BIO_R_INVALID_SOCKET);
214 return 0;
215 }
216
217 if (getsockopt(sock, SOL_SOCKET, SO_TYPE,
218 (void *)&socktype, &socktype_len) != 0
219 || socktype_len != sizeof(socktype)) {
220 SYSerr(SYS_F_GETSOCKOPT, get_last_socket_error());
221 BIOerr(BIO_F_BIO_LISTEN, BIO_R_GETTING_SOCKTYPE);
222 return 0;
223 }
224
225 if (!BIO_socket_nbio(sock, (options & BIO_SOCK_NONBLOCK) != 0))
226 return 0;
227
228 if (options & BIO_SOCK_KEEPALIVE) {
229 if (setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
230 (const void *)&on, sizeof(on)) != 0) {
231 SYSerr(SYS_F_SETSOCKOPT, get_last_socket_error());
232 BIOerr(BIO_F_BIO_LISTEN, BIO_R_UNABLE_TO_KEEPALIVE);
233 return 0;
234 }
235 }
236
237 if (options & BIO_SOCK_NODELAY) {
238 if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY,
239 (const void *)&on, sizeof(on)) != 0) {
240 SYSerr(SYS_F_SETSOCKOPT, get_last_socket_error());
241 BIOerr(BIO_F_BIO_LISTEN, BIO_R_UNABLE_TO_NODELAY);
242 return 0;
243 }
244 }
245
246 /* On OpenBSD it is always ipv6 only with ipv6 sockets thus read-only */
247 # if defined(IPV6_V6ONLY) && !defined(__OpenBSD__)
248 if (BIO_ADDR_family(addr) == AF_INET6) {
249 /*
250 * Note: Windows default of IPV6_V6ONLY is ON, and Linux is OFF.
251 * Therefore we always have to use setsockopt here.
252 */
253 on = options & BIO_SOCK_V6_ONLY ? 1 : 0;
254 if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY,
255 (const void *)&on, sizeof(on)) != 0) {
256 SYSerr(SYS_F_SETSOCKOPT, get_last_socket_error());
257 BIOerr(BIO_F_BIO_LISTEN, BIO_R_LISTEN_V6_ONLY);
258 return 0;
259 }
260 }
261 # endif
262
263 if (!BIO_bind(sock, addr, options))
264 return 0;
265
266 if (socktype != SOCK_DGRAM && listen(sock, MAX_LISTEN) == -1) {
267 SYSerr(SYS_F_LISTEN, get_last_socket_error());
268 BIOerr(BIO_F_BIO_LISTEN, BIO_R_UNABLE_TO_LISTEN_SOCKET);
269 return 0;
270 }
271
272 return 1;
273 }
274
275 /*-
276 * BIO_accept_ex - Accept new incoming connections
277 * @sock: the listening socket
278 * @addr: the BIO_ADDR to store the peer address in
279 * @options: BIO socket options, applied on the accepted socket.
280 *
281 */
BIO_accept_ex(int accept_sock,BIO_ADDR * addr_,int options)282 int BIO_accept_ex(int accept_sock, BIO_ADDR *addr_, int options)
283 {
284 socklen_t len;
285 int accepted_sock;
286 BIO_ADDR locaddr;
287 BIO_ADDR *addr = addr_ == NULL ? &locaddr : addr_;
288
289 len = sizeof(*addr);
290 accepted_sock = accept(accept_sock,
291 BIO_ADDR_sockaddr_noconst(addr), &len);
292 if (accepted_sock == -1) {
293 if (!BIO_sock_should_retry(accepted_sock)) {
294 SYSerr(SYS_F_ACCEPT, get_last_socket_error());
295 BIOerr(BIO_F_BIO_ACCEPT_EX, BIO_R_ACCEPT_ERROR);
296 }
297 return INVALID_SOCKET;
298 }
299
300 if (!BIO_socket_nbio(accepted_sock, (options & BIO_SOCK_NONBLOCK) != 0)) {
301 closesocket(accepted_sock);
302 return INVALID_SOCKET;
303 }
304
305 return accepted_sock;
306 }
307
308 /*-
309 * BIO_closesocket - Close a socket
310 * @sock: the socket to close
311 */
BIO_closesocket(int sock)312 int BIO_closesocket(int sock)
313 {
314 if (closesocket(sock) < 0)
315 return 0;
316 return 1;
317 }
318 #endif
319