2 Copyright (C) 2000 Free Software Foundation, Inc.
3 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>
56 #include "gen_sslfunc.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
75 /* First, seed from a file specified by the user. This will be
76 $RANDFILE, if set, or ~/.rnd. */
77 RAND_file_name (rand_file, sizeof (rand_file));
79 /* Seed at most 16k (value borrowed from curl) from random file. */
80 RAND_load_file (rand_file, 16384);
85 /* Get random data from EGD if opt.sslegdsock was set. */
86 if (opt.sslegdsock && *opt.sslegdsock)
87 RAND_egd (opt.sslegdsock);
93 /* Under Windows, we can try to seed the PRNG using screen content.
94 This may or may not work, depending on whether we'll calling Wget
102 /* Still not enough randomness, most likely because neither
103 /dev/random nor EGD were available. Resort to a simple and
104 stupid method -- seed OpenSSL's PRNG with libc PRNG. This is
105 cryptographically weak, but people who care about strong
106 cryptography should install /dev/random (default on Linux) or
107 specify their own source of randomness anyway. */
109 logprintf (LOG_VERBOSE, _("Warning: using a weak random seed.\n"));
111 while (RAND_status () == 0 && maxrand-- > 0)
113 unsigned char rnd = random_number (256);
114 RAND_seed (&rnd, sizeof (rnd));
116 #endif /* SSLEAY_VERSION_NUMBER >= 0x00905100 */
120 verify_callback (int ok, X509_STORE_CTX *ctx)
123 s = X509_NAME_oneline (X509_get_subject_name (ctx->current_cert), buf, 256);
125 switch (ctx->error) {
126 case X509_V_ERR_CERT_NOT_YET_VALID:
127 case X509_V_ERR_CERT_HAS_EXPIRED:
128 /* This mean the CERT is not valid !!! */
131 case X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT:
132 /* Unsure if we should handle that this way */
140 /* Print SSL errors. */
143 ssl_print_errors (void)
145 unsigned long curerr = 0;
146 while ((curerr = ERR_get_error ()) != 0)
147 logprintf (LOG_NOTQUIET, "OpenSSL: %s\n", ERR_error_string (curerr, NULL));
150 /* Creates a SSL Context and sets some defaults for it */
154 SSL_METHOD *meth = NULL;
161 /* Init the PRNG. If that fails, bail out. */
163 if (RAND_status () == 0)
165 logprintf (LOG_NOTQUIET,
166 _("Could not seed OpenSSL PRNG; disabling SSL.\n"));
167 scheme_disable (SCHEME_HTTPS);
168 return SSLERRCTXCREATE;
172 SSL_load_error_strings ();
173 SSLeay_add_all_algorithms ();
174 SSLeay_add_ssl_algorithms ();
175 switch (opt.sslprotocol)
178 meth = SSLv23_client_method ();
181 meth = SSLv2_client_method ();
184 meth = SSLv3_client_method ();
187 meth = TLSv1_client_method ();
193 return SSLERRCTXCREATE;
196 ssl_ctx = SSL_CTX_new (meth);
200 return SSLERRCTXCREATE;
202 /* Can we validate the server Cert ? */
203 if (opt.sslcadir != NULL || opt.sslcafile != NULL)
205 SSL_CTX_load_verify_locations (ssl_ctx, opt.sslcafile, opt.sslcadir);
213 if (!opt.sslcheckcert)
215 /* check cert but ignore error, do not break handshake on error */
216 verify = SSL_VERIFY_NONE;
222 logputs (LOG_NOTQUIET,
223 _("Warning: validation of server certificate not possible!\n"));
224 verify = SSL_VERIFY_NONE;
228 /* break handshake if server cert is not valid but allow
230 verify = SSL_VERIFY_PEER;
234 SSL_CTX_set_verify (ssl_ctx, verify, verify_callback);
236 if (opt.sslcertfile != NULL || opt.sslcertkey != NULL)
239 if (!opt.sslcerttype)
240 ssl_cert_type = SSL_FILETYPE_PEM;
242 ssl_cert_type = SSL_FILETYPE_ASN1;
244 if (opt.sslcertkey == NULL)
245 opt.sslcertkey = opt.sslcertfile;
246 if (opt.sslcertfile == NULL)
247 opt.sslcertfile = opt.sslcertkey;
249 if (SSL_CTX_use_certificate_file (ssl_ctx, opt.sslcertfile,
253 return SSLERRCERTFILE;
255 if (SSL_CTX_use_PrivateKey_file (ssl_ctx, opt.sslcertkey,
259 return SSLERRCERTKEY;
263 return 0; /* Succeded */
267 ssl_read (int fd, char *buf, int bufsize, void *ctx)
270 SSL *ssl = (SSL *) ctx;
272 ret = SSL_read (ssl, buf, bufsize);
274 && SSL_get_error (ssl, ret) == SSL_ERROR_SYSCALL
280 ssl_write (int fd, char *buf, int bufsize, void *ctx)
283 SSL *ssl = (SSL *) ctx;
285 ret = SSL_write (ssl, buf, bufsize);
287 && SSL_get_error (ssl, ret) == SSL_ERROR_SYSCALL
293 ssl_poll (int fd, double timeout, int wait_for, void *ctx)
295 SSL *ssl = (SSL *) ctx;
298 if (SSL_pending (ssl))
300 return select_fd (fd, timeout, wait_for);
304 ssl_peek (int fd, char *buf, int bufsize, void *ctx)
307 SSL *ssl = (SSL *) ctx;
309 ret = SSL_peek (ssl, buf, bufsize);
311 && SSL_get_error (ssl, ret) == SSL_ERROR_SYSCALL
317 ssl_close (int fd, void *ctx)
319 SSL *ssl = (SSL *) ctx;
329 DEBUGP (("Closed %d/SSL 0x%0lx\n", fd, (unsigned long) ssl));
332 /* Sets up a SSL structure and performs the handshake on fd. The
333 resulting SSL structure is registered with the file descriptor FD
334 using fd_register_transport. That way subsequent calls to xread,
335 xwrite, etc., will use the appropriate SSL functions.
337 Returns 1 on success, 0 on failure. */
344 assert (ssl_ctx != NULL);
345 ssl = SSL_new (ssl_ctx);
348 if (!SSL_set_fd (ssl, fd))
350 SSL_set_connect_state (ssl);
351 if (SSL_connect (ssl) <= 0 || ssl->state != SSL_ST_OK)
354 /* Register FD with Wget's transport layer, i.e. arrange that
355 SSL-enabled functions are used for reading, writing, and polling.
356 That way the rest of Wget can keep using xread, xwrite, and
357 friends and not care what happens underneath. */
358 fd_register_transport (fd, ssl_read, ssl_write, ssl_poll, ssl_peek,
360 DEBUGP (("Connected %d to SSL 0x%0*lx\n", fd, 2 * sizeof (void *),
361 (unsigned long) ssl));