2 * Copyright (c) 2008 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
5 * by Matthias Schmidt <matthias@dragonflybsd.org>, University of Marburg,
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
18 * 3. Neither the name of The DragonFly Project nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific, prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
26 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
28 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
30 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
32 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * $DragonFly: src/libexec/dma/crypto.c,v 1.4 2008/09/30 17:47:21 swildner Exp $
38 #include <openssl/x509.h>
39 #include <openssl/md5.h>
40 #include <openssl/ssl.h>
41 #include <openssl/err.h>
42 #include <openssl/pem.h>
43 #include <openssl/rand.h>
49 extern struct config *config;
52 init_cert_file(struct qitem *it, SSL_CTX *ctx, const char *path)
56 /* Load certificate into ctx */
57 error = SSL_CTX_use_certificate_chain_file(ctx, path);
59 syslog(LOG_ERR, "%s: SSL: Cannot load certificate `%s': %s",
60 it->queueid, path, ssl_errstr());
64 /* Add private key to ctx */
65 error = SSL_CTX_use_PrivateKey_file(ctx, path, SSL_FILETYPE_PEM);
67 syslog(LOG_ERR, "%s: SSL: Cannot load private key `%s': %s",
68 it->queueid, path, ssl_errstr());
73 * Check the consistency of a private key with the corresponding
76 error = SSL_CTX_check_private_key(ctx);
78 syslog(LOG_ERR, "%s: SSL: Cannot check private key: %s",
79 it->queueid, ssl_errstr());
87 smtp_init_crypto(struct qitem *it, int fd, int feature)
90 SSL_METHOD *meth = NULL;
94 /* XXX clean up on error/close */
95 /* Init SSL library */
97 SSL_load_error_strings();
99 meth = TLSv1_client_method();
101 ctx = SSL_CTX_new(meth);
103 syslog(LOG_WARNING, "%s: remote delivery deferred: SSL init failed: %s",
104 it->queueid, ssl_errstr());
108 /* User supplied a certificate */
109 if (config->certfile != NULL) {
110 error = init_cert_file(it, ctx, config->certfile);
112 syslog(LOG_WARNING, "%s: remote delivery deferred", it->queueid);
118 * If the user wants STARTTLS, we have to send EHLO here
120 if (((feature & SECURETRANS) != 0) &&
121 (feature & STARTTLS) != 0) {
122 /* TLS init phase, disable SSL_write */
123 config->features |= NOSSL;
125 send_remote_command(fd, "EHLO %s", hostname());
126 if (read_remote(fd, 0, NULL) == 2) {
127 send_remote_command(fd, "STARTTLS");
128 if (read_remote(fd, 0, NULL) != 2) {
129 syslog(LOG_ERR, "%s: remote delivery deferred:"
130 " STARTTLS not available: %s", it->queueid,
132 config->features &= ~NOSSL;
136 /* End of TLS init phase, enable SSL_write/read */
137 config->features &= ~NOSSL;
140 config->ssl = SSL_new(ctx);
141 if (config->ssl == NULL) {
142 syslog(LOG_NOTICE, "%s: remote delivery deferred: SSL struct creation failed: %s",
143 it->queueid, ssl_errstr());
147 /* Set ssl to work in client mode */
148 SSL_set_connect_state(config->ssl);
150 /* Set fd for SSL in/output */
151 error = SSL_set_fd(config->ssl, fd);
153 syslog(LOG_NOTICE, "%s: remote delivery deferred: SSL set fd failed: %s",
154 it->queueid, ssl_errstr());
158 /* Open SSL connection */
159 error = SSL_connect(config->ssl);
161 syslog(LOG_ERR, "%s: remote delivery deferred: SSL handshake failed fatally: %s",
162 it->queueid, ssl_errstr());
166 /* Get peer certificate */
167 cert = SSL_get_peer_certificate(config->ssl);
169 syslog(LOG_WARNING, "%s: remote delivery deferred: Peer did not provide certificate: %s",
170 it->queueid, ssl_errstr());
178 * hmac_md5() taken out of RFC 2104. This RFC was written by H. Krawczyk,
179 * M. Bellare and R. Canetti.
181 * text pointer to data stream
182 * text_len length of data stream
183 * key pointer to authentication key
184 * key_len length of authentication key
185 * digest caller digest to be filled int
188 hmac_md5(unsigned char *text, int text_len, unsigned char *key, int key_len,
192 unsigned char k_ipad[65]; /* inner padding -
195 unsigned char k_opad[65]; /* outer padding -
198 unsigned char tk[16];
200 /* if key is longer than 64 bytes reset it to key=MD5(key) */
206 MD5_Update(&tctx, key, key_len);
207 MD5_Final(tk, &tctx);
214 * the HMAC_MD5 transform looks like:
216 * MD5(K XOR opad, MD5(K XOR ipad, text))
218 * where K is an n byte key
219 * ipad is the byte 0x36 repeated 64 times
221 * opad is the byte 0x5c repeated 64 times
222 * and text is the data being protected
225 /* start out by storing key in pads */
226 bzero( k_ipad, sizeof k_ipad);
227 bzero( k_opad, sizeof k_opad);
228 bcopy( key, k_ipad, key_len);
229 bcopy( key, k_opad, key_len);
231 /* XOR key with ipad and opad values */
232 for (i=0; i<64; i++) {
239 MD5_Init(&context); /* init context for 1st
241 MD5_Update(&context, k_ipad, 64); /* start with inner pad */
242 MD5_Update(&context, text, text_len); /* then text of datagram */
243 MD5_Final(digest, &context); /* finish up 1st pass */
247 MD5_Init(&context); /* init context for 2nd
249 MD5_Update(&context, k_opad, 64); /* start with outer pad */
250 MD5_Update(&context, digest, 16); /* then results of 1st
252 MD5_Final(digest, &context); /* finish up 2nd pass */
256 * CRAM-MD5 authentication
259 smtp_auth_md5(struct qitem *it, int fd, char *login, char *password)
261 unsigned char buffer[BUF_SIZE], digest[BUF_SIZE], ascii_digest[33];
264 static char hextab[] = "0123456789abcdef";
266 temp = calloc(BUF_SIZE, 1);
267 memset(buffer, 0, sizeof(buffer));
268 memset(digest, 0, sizeof(digest));
269 memset(ascii_digest, 0, sizeof(ascii_digest));
271 /* Send AUTH command according to RFC 2554 */
272 send_remote_command(fd, "AUTH CRAM-MD5");
273 if (read_remote(fd, sizeof(buffer), buffer) != 3) {
274 syslog(LOG_DEBUG, "%s: smarthost authentification:"
275 " AUTH cram-md5 not available: %s", it->queueid,
277 /* if cram-md5 is not available */
281 /* skip 3 char status + 1 char space */
282 base64_decode(buffer + 4, temp);
283 hmac_md5(temp, strlen(temp), password, strlen(password), digest);
286 ascii_digest[32] = 0;
287 for (i = 0; i < 16; i++) {
288 ascii_digest[2*i] = hextab[digest[i] >> 4];
289 ascii_digest[2*i+1] = hextab[digest[i] & 15];
293 snprintf(buffer, BUF_SIZE, "%s %s", login, ascii_digest);
296 len = base64_encode(buffer, strlen(buffer), &temp);
298 syslog(LOG_ERR, "%s: can not encode auth reply: %m",
304 send_remote_command(fd, "%s", temp);
306 if (read_remote(fd, 0, NULL) != 2) {
307 syslog(LOG_WARNING, "%s: remote delivery deferred:"
308 " AUTH cram-md5 failed: %s", it->queueid,