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>
50 init_cert_file(struct qitem *it, SSL_CTX *ctx, const char *path)
54 /* Load certificate into ctx */
55 error = SSL_CTX_use_certificate_chain_file(ctx, path);
57 syslog(LOG_ERR, "%s: SSL: Cannot load certificate `%s': %s",
58 it->queueid, path, ssl_errstr());
62 /* Add private key to ctx */
63 error = SSL_CTX_use_PrivateKey_file(ctx, path, SSL_FILETYPE_PEM);
65 syslog(LOG_ERR, "%s: SSL: Cannot load private key `%s': %s",
66 it->queueid, path, ssl_errstr());
71 * Check the consistency of a private key with the corresponding
74 error = SSL_CTX_check_private_key(ctx);
76 syslog(LOG_ERR, "%s: SSL: Cannot check private key: %s",
77 it->queueid, ssl_errstr());
85 smtp_init_crypto(struct qitem *it, int fd, int feature)
88 SSL_METHOD *meth = NULL;
92 /* XXX clean up on error/close */
93 /* Init SSL library */
95 SSL_load_error_strings();
97 meth = TLSv1_client_method();
99 ctx = SSL_CTX_new(meth);
101 syslog(LOG_WARNING, "%s: remote delivery deferred: SSL init failed: %s",
102 it->queueid, ssl_errstr());
106 /* User supplied a certificate */
107 if (config->certfile != NULL) {
108 error = init_cert_file(it, ctx, config->certfile);
110 syslog(LOG_WARNING, "%s: remote delivery deferred", it->queueid);
116 * If the user wants STARTTLS, we have to send EHLO here
118 if (((feature & SECURETRANS) != 0) &&
119 (feature & STARTTLS) != 0) {
120 /* TLS init phase, disable SSL_write */
121 config->features |= NOSSL;
123 send_remote_command(fd, "EHLO %s", hostname());
124 if (read_remote(fd, 0, NULL) == 2) {
125 send_remote_command(fd, "STARTTLS");
126 if (read_remote(fd, 0, NULL) != 2) {
127 syslog(LOG_ERR, "%s: remote delivery deferred:"
128 " STARTTLS not available: %s", it->queueid,
130 config->features &= ~NOSSL;
134 /* End of TLS init phase, enable SSL_write/read */
135 config->features &= ~NOSSL;
138 config->ssl = SSL_new(ctx);
139 if (config->ssl == NULL) {
140 syslog(LOG_NOTICE, "%s: remote delivery deferred: SSL struct creation failed: %s",
141 it->queueid, ssl_errstr());
145 /* Set ssl to work in client mode */
146 SSL_set_connect_state(config->ssl);
148 /* Set fd for SSL in/output */
149 error = SSL_set_fd(config->ssl, fd);
151 syslog(LOG_NOTICE, "%s: remote delivery deferred: SSL set fd failed: %s",
152 it->queueid, ssl_errstr());
156 /* Open SSL connection */
157 error = SSL_connect(config->ssl);
159 syslog(LOG_ERR, "%s: remote delivery deferred: SSL handshake failed fatally: %s",
160 it->queueid, ssl_errstr());
164 /* Get peer certificate */
165 cert = SSL_get_peer_certificate(config->ssl);
167 syslog(LOG_WARNING, "%s: remote delivery deferred: Peer did not provide certificate: %s",
168 it->queueid, ssl_errstr());
176 * hmac_md5() taken out of RFC 2104. This RFC was written by H. Krawczyk,
177 * M. Bellare and R. Canetti.
179 * text pointer to data stream
180 * text_len length of data stream
181 * key pointer to authentication key
182 * key_len length of authentication key
183 * digest caller digest to be filled int
186 hmac_md5(unsigned char *text, int text_len, unsigned char *key, int key_len,
190 unsigned char k_ipad[65]; /* inner padding -
193 unsigned char k_opad[65]; /* outer padding -
196 unsigned char tk[16];
198 /* if key is longer than 64 bytes reset it to key=MD5(key) */
204 MD5_Update(&tctx, key, key_len);
205 MD5_Final(tk, &tctx);
212 * the HMAC_MD5 transform looks like:
214 * MD5(K XOR opad, MD5(K XOR ipad, text))
216 * where K is an n byte key
217 * ipad is the byte 0x36 repeated 64 times
219 * opad is the byte 0x5c repeated 64 times
220 * and text is the data being protected
223 /* start out by storing key in pads */
224 bzero( k_ipad, sizeof k_ipad);
225 bzero( k_opad, sizeof k_opad);
226 bcopy( key, k_ipad, key_len);
227 bcopy( key, k_opad, key_len);
229 /* XOR key with ipad and opad values */
230 for (i=0; i<64; i++) {
237 MD5_Init(&context); /* init context for 1st
239 MD5_Update(&context, k_ipad, 64); /* start with inner pad */
240 MD5_Update(&context, text, text_len); /* then text of datagram */
241 MD5_Final(digest, &context); /* finish up 1st pass */
245 MD5_Init(&context); /* init context for 2nd
247 MD5_Update(&context, k_opad, 64); /* start with outer pad */
248 MD5_Update(&context, digest, 16); /* then results of 1st
250 MD5_Final(digest, &context); /* finish up 2nd pass */
254 * CRAM-MD5 authentication
257 smtp_auth_md5(struct qitem *it, int fd, char *login, char *password)
259 unsigned char buffer[BUF_SIZE], digest[BUF_SIZE], ascii_digest[33];
262 static char hextab[] = "0123456789abcdef";
264 temp = calloc(BUF_SIZE, 1);
265 memset(buffer, 0, sizeof(buffer));
266 memset(digest, 0, sizeof(digest));
267 memset(ascii_digest, 0, sizeof(ascii_digest));
269 /* Send AUTH command according to RFC 2554 */
270 send_remote_command(fd, "AUTH CRAM-MD5");
271 if (read_remote(fd, sizeof(buffer), buffer) != 3) {
272 syslog(LOG_DEBUG, "%s: smarthost authentification:"
273 " AUTH cram-md5 not available: %s", it->queueid,
275 /* if cram-md5 is not available */
279 /* skip 3 char status + 1 char space */
280 base64_decode(buffer + 4, temp);
281 hmac_md5(temp, strlen(temp), password, strlen(password), digest);
284 ascii_digest[32] = 0;
285 for (i = 0; i < 16; i++) {
286 ascii_digest[2*i] = hextab[digest[i] >> 4];
287 ascii_digest[2*i+1] = hextab[digest[i] & 15];
291 snprintf(buffer, BUF_SIZE, "%s %s", login, ascii_digest);
294 len = base64_encode(buffer, strlen(buffer), &temp);
296 syslog(LOG_ERR, "%s: can not encode auth reply: %m",
302 send_remote_command(fd, "%s", temp);
304 if (read_remote(fd, 0, NULL) != 2) {
305 syslog(LOG_WARNING, "%s: remote delivery deferred:"
306 " AUTH cram-md5 failed: %s", it->queueid,