1 /* SSL support via OpenSSL library.
2 Copyright (C) 2000-2005 Free Software Foundation, Inc.
3 Originally contributed by Christian Fraenkel.
5 This file is part of GNU Wget.
7 GNU Wget is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 GNU Wget is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with Wget; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 In addition, as a special exception, the Free Software Foundation
22 gives permission to link the code of its release of Wget with the
23 OpenSSL project's "OpenSSL" library (or with modified versions of it
24 that use the same license as the "OpenSSL" library), and distribute
25 the linked executables. You must obey the GNU General Public License
26 in all respects for all of the code used other than "OpenSSL". If you
27 modify this file, you may extend this exception to your version of the
28 file, but you are not obligated to do so. If you do not wish to do
29 so, delete this exception statement from your version. */
44 #include <openssl/bio.h>
45 #include <openssl/crypto.h>
46 #include <openssl/x509.h>
47 #include <openssl/ssl.h>
48 #include <openssl/err.h>
49 #include <openssl/pem.h>
50 #include <openssl/rand.h>
67 /* It is likely that older versions of OpenSSL will fail on
68 non-Linux machines because this code is unable to seed the PRNG
69 on older versions of the library. */
71 #if SSLEAY_VERSION_NUMBER >= 0x00905100
74 /* First, seed from a file specified by the user. This will be
75 $RANDFILE, if set, or ~/.rnd. */
76 RAND_file_name (rand_file, sizeof (rand_file));
78 /* Seed at most 16k (value borrowed from curl) from random file. */
79 RAND_load_file (rand_file, 16384);
84 /* Get random data from EGD if opt.egd_file was set. */
85 if (opt.egd_file && *opt.egd_file)
86 RAND_egd (opt.egd_file);
92 /* Under Windows, we can try to seed the PRNG using screen content.
93 This may or may not work, depending on whether we'll calling Wget
101 #if 0 /* don't do this by default */
105 /* Still not random enough, presumably because neither /dev/random
106 nor EGD were available. Try to seed OpenSSL's PRNG with libc
107 PRNG. This is cryptographically weak and defeats the purpose
108 of using OpenSSL, which is why it is highly discouraged. */
110 logprintf (LOG_VERBOSE, _("WARNING: using a weak random seed.\n"));
112 while (RAND_status () == 0 && maxrand-- > 0)
114 unsigned char rnd = random_number (256);
115 RAND_seed (&rnd, sizeof (rnd));
120 #endif /* SSLEAY_VERSION_NUMBER >= 0x00905100 */
124 verify_callback (int ok, X509_STORE_CTX *ctx)
127 s = X509_NAME_oneline (X509_get_subject_name (ctx->current_cert),
133 case X509_V_ERR_CERT_NOT_YET_VALID:
134 case X509_V_ERR_CERT_HAS_EXPIRED:
135 /* This mean the CERT is not valid !!! */
138 case X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT:
139 /* Unsure if we should handle that this way */
147 /* Print SSL errors. */
150 ssl_print_errors (void)
152 unsigned long curerr = 0;
153 while ((curerr = ERR_get_error ()) != 0)
154 logprintf (LOG_NOTQUIET, "OpenSSL: %s\n", ERR_error_string (curerr, NULL));
157 /* Convert keyfile type as used by options.h to a type as accepted by
158 SSL_CTX_use_certificate_file and SSL_CTX_use_PrivateKey_file.
160 (options.h intentionally doesn't use values from openssl/ssl.h so
161 it doesn't depend specifically on OpenSSL for SSL functionality.) */
164 key_type_to_ssl_type (enum keyfile_type type)
169 return SSL_FILETYPE_PEM;
171 return SSL_FILETYPE_ASN1;
177 /* Creates a SSL Context and sets some defaults for it */
181 SSL_METHOD *meth = NULL;
186 /* Init the PRNG. If that fails, bail out. */
188 if (RAND_status () == 0)
190 logprintf (LOG_NOTQUIET,
191 _("Could not seed OpenSSL PRNG; disabling SSL.\n"));
192 scheme_disable (SCHEME_HTTPS);
193 return SSLERRCTXCREATE;
197 SSL_load_error_strings ();
198 SSLeay_add_all_algorithms ();
199 SSLeay_add_ssl_algorithms ();
200 switch (opt.secure_protocol)
202 case secure_protocol_auto:
203 meth = SSLv23_client_method ();
205 case secure_protocol_sslv2:
206 meth = SSLv2_client_method ();
208 case secure_protocol_sslv3:
209 meth = SSLv3_client_method ();
211 case secure_protocol_tlsv1:
212 meth = TLSv1_client_method ();
218 ssl_ctx = SSL_CTX_new (meth);
219 SSL_CTX_set_default_verify_paths (ssl_ctx);
220 SSL_CTX_load_verify_locations (ssl_ctx, opt.ca_cert, opt.ca_directory);
221 SSL_CTX_set_verify (ssl_ctx,
222 opt.check_cert ? SSL_VERIFY_PEER : SSL_VERIFY_NONE,
226 if (SSL_CTX_use_certificate_file (ssl_ctx, opt.cert_file,
227 key_type_to_ssl_type (opt.cert_type))
231 return SSLERRCERTFILE;
234 if (SSL_CTX_use_PrivateKey_file (ssl_ctx, opt.private_key,
235 key_type_to_ssl_type (opt.private_key_type))
239 return SSLERRCERTKEY;
242 return 0; /* Succeded */
246 ssl_read (int fd, char *buf, int bufsize, void *ctx)
249 SSL *ssl = (SSL *) ctx;
251 ret = SSL_read (ssl, buf, bufsize);
253 && SSL_get_error (ssl, ret) == SSL_ERROR_SYSCALL
259 ssl_write (int fd, char *buf, int bufsize, void *ctx)
262 SSL *ssl = (SSL *) ctx;
264 ret = SSL_write (ssl, buf, bufsize);
266 && SSL_get_error (ssl, ret) == SSL_ERROR_SYSCALL
272 ssl_poll (int fd, double timeout, int wait_for, void *ctx)
274 SSL *ssl = (SSL *) ctx;
277 if (SSL_pending (ssl))
279 return select_fd (fd, timeout, wait_for);
283 ssl_peek (int fd, char *buf, int bufsize, void *ctx)
286 SSL *ssl = (SSL *) ctx;
288 ret = SSL_peek (ssl, buf, bufsize);
290 && SSL_get_error (ssl, ret) == SSL_ERROR_SYSCALL
296 ssl_close (int fd, void *ctx)
298 SSL *ssl = (SSL *) ctx;
308 DEBUGP (("Closed %d/SSL 0x%0lx\n", fd, (unsigned long) ssl));
311 /* Sets up a SSL structure and performs the handshake on fd. The
312 resulting SSL structure is registered with the file descriptor FD
313 using fd_register_transport. That way subsequent calls to xread,
314 xwrite, etc., will use the appropriate SSL functions.
316 Returns 1 on success, 0 on failure. */
323 assert (ssl_ctx != NULL);
324 ssl = SSL_new (ssl_ctx);
327 if (!SSL_set_fd (ssl, fd))
329 SSL_set_connect_state (ssl);
330 if (SSL_connect (ssl) <= 0 || ssl->state != SSL_ST_OK)
333 /* Register FD with Wget's transport layer, i.e. arrange that
334 SSL-enabled functions are used for reading, writing, and polling.
335 That way the rest of Wget can keep using xread, xwrite, and
336 friends and not care what happens underneath. */
337 fd_register_transport (fd, ssl_read, ssl_write, ssl_poll, ssl_peek,
339 DEBUGP (("Connected %d to SSL 0x%0*lx\n", fd, 2 * sizeof (void *),
340 (unsigned long) ssl));