Merge branch 'master' of ssh://crater.dragonflybsd.org/repository/git/dragonfly
[dragonfly.git] / libexec / dma / crypto.c
blob009de81190401e19a7fe230d44100d6e885a9ac3
1 /*
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,
6 * Germany.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
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
17 * distribution.
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
33 * SUCH DAMAGE.
36 #include <openssl/x509.h>
37 #include <openssl/md5.h>
38 #include <openssl/ssl.h>
39 #include <openssl/err.h>
40 #include <openssl/pem.h>
41 #include <openssl/rand.h>
43 #include <syslog.h>
45 #include "dma.h"
47 static int
48 init_cert_file(SSL_CTX *ctx, const char *path)
50 int error;
52 /* Load certificate into ctx */
53 error = SSL_CTX_use_certificate_chain_file(ctx, path);
54 if (error < 1) {
55 syslog(LOG_ERR, "SSL: Cannot load certificate `%s': %s", path, ssl_errstr());
56 return (-1);
59 /* Add private key to ctx */
60 error = SSL_CTX_use_PrivateKey_file(ctx, path, SSL_FILETYPE_PEM);
61 if (error < 1) {
62 syslog(LOG_ERR, "SSL: Cannot load private key `%s': %s", path, ssl_errstr());
63 return (-1);
67 * Check the consistency of a private key with the corresponding
68 * certificate
70 error = SSL_CTX_check_private_key(ctx);
71 if (error < 1) {
72 syslog(LOG_ERR, "SSL: Cannot check private key: %s", ssl_errstr());
73 return (-1);
76 return (0);
79 int
80 smtp_init_crypto(int fd, int feature)
82 SSL_CTX *ctx = NULL;
83 SSL_METHOD *meth = NULL;
84 X509 *cert;
85 int error;
87 /* XXX clean up on error/close */
88 /* Init SSL library */
89 SSL_library_init();
90 SSL_load_error_strings();
92 meth = TLSv1_client_method();
94 ctx = SSL_CTX_new(meth);
95 if (ctx == NULL) {
96 syslog(LOG_WARNING, "remote delivery deferred: SSL init failed: %s", ssl_errstr());
97 return (1);
100 /* User supplied a certificate */
101 if (config.certfile != NULL) {
102 error = init_cert_file(ctx, config.certfile);
103 if (error) {
104 syslog(LOG_WARNING, "remote delivery deferred");
105 return (1);
110 * If the user wants STARTTLS, we have to send EHLO here
112 if (((feature & SECURETRANS) != 0) &&
113 (feature & STARTTLS) != 0) {
114 /* TLS init phase, disable SSL_write */
115 config.features |= NOSSL;
117 send_remote_command(fd, "EHLO %s", hostname());
118 if (read_remote(fd, 0, NULL) == 2) {
119 send_remote_command(fd, "STARTTLS");
120 if (read_remote(fd, 0, NULL) != 2) {
121 syslog(LOG_ERR, "remote delivery deferred:"
122 " STARTTLS not available: %s", neterr);
123 return (1);
126 /* End of TLS init phase, enable SSL_write/read */
127 config.features &= ~NOSSL;
130 config.ssl = SSL_new(ctx);
131 if (config.ssl == NULL) {
132 syslog(LOG_NOTICE, "remote delivery deferred: SSL struct creation failed: %s",
133 ssl_errstr());
134 return (1);
137 /* Set ssl to work in client mode */
138 SSL_set_connect_state(config.ssl);
140 /* Set fd for SSL in/output */
141 error = SSL_set_fd(config.ssl, fd);
142 if (error == 0) {
143 syslog(LOG_NOTICE, "remote delivery deferred: SSL set fd failed: %s",
144 ssl_errstr());
145 return (1);
148 /* Open SSL connection */
149 error = SSL_connect(config.ssl);
150 if (error < 0) {
151 syslog(LOG_ERR, "remote delivery deferred: SSL handshake failed fatally: %s",
152 ssl_errstr());
153 return (1);
156 /* Get peer certificate */
157 cert = SSL_get_peer_certificate(config.ssl);
158 if (cert == NULL) {
159 syslog(LOG_WARNING, "remote delivery deferred: Peer did not provide certificate: %s",
160 ssl_errstr());
162 X509_free(cert);
164 return (0);
168 * hmac_md5() taken out of RFC 2104. This RFC was written by H. Krawczyk,
169 * M. Bellare and R. Canetti.
171 * text pointer to data stream
172 * text_len length of data stream
173 * key pointer to authentication key
174 * key_len length of authentication key
175 * digest caller digest to be filled int
177 void
178 hmac_md5(unsigned char *text, int text_len, unsigned char *key, int key_len,
179 caddr_t digest)
181 MD5_CTX context;
182 unsigned char k_ipad[65]; /* inner padding -
183 * key XORd with ipad
185 unsigned char k_opad[65]; /* outer padding -
186 * key XORd with opad
188 unsigned char tk[16];
189 int i;
190 /* if key is longer than 64 bytes reset it to key=MD5(key) */
191 if (key_len > 64) {
193 MD5_CTX tctx;
195 MD5_Init(&tctx);
196 MD5_Update(&tctx, key, key_len);
197 MD5_Final(tk, &tctx);
199 key = tk;
200 key_len = 16;
204 * the HMAC_MD5 transform looks like:
206 * MD5(K XOR opad, MD5(K XOR ipad, text))
208 * where K is an n byte key
209 * ipad is the byte 0x36 repeated 64 times
211 * opad is the byte 0x5c repeated 64 times
212 * and text is the data being protected
215 /* start out by storing key in pads */
216 bzero( k_ipad, sizeof k_ipad);
217 bzero( k_opad, sizeof k_opad);
218 bcopy( key, k_ipad, key_len);
219 bcopy( key, k_opad, key_len);
221 /* XOR key with ipad and opad values */
222 for (i=0; i<64; i++) {
223 k_ipad[i] ^= 0x36;
224 k_opad[i] ^= 0x5c;
227 * perform inner MD5
229 MD5_Init(&context); /* init context for 1st
230 * pass */
231 MD5_Update(&context, k_ipad, 64); /* start with inner pad */
232 MD5_Update(&context, text, text_len); /* then text of datagram */
233 MD5_Final(digest, &context); /* finish up 1st pass */
235 * perform outer MD5
237 MD5_Init(&context); /* init context for 2nd
238 * pass */
239 MD5_Update(&context, k_opad, 64); /* start with outer pad */
240 MD5_Update(&context, digest, 16); /* then results of 1st
241 * hash */
242 MD5_Final(digest, &context); /* finish up 2nd pass */
246 * CRAM-MD5 authentication
249 smtp_auth_md5(int fd, char *login, char *password)
251 unsigned char buffer[BUF_SIZE], digest[BUF_SIZE], ascii_digest[33];
252 char *temp;
253 int len, i;
254 static char hextab[] = "0123456789abcdef";
256 temp = calloc(BUF_SIZE, 1);
257 memset(buffer, 0, sizeof(buffer));
258 memset(digest, 0, sizeof(digest));
259 memset(ascii_digest, 0, sizeof(ascii_digest));
261 /* Send AUTH command according to RFC 2554 */
262 send_remote_command(fd, "AUTH CRAM-MD5");
263 if (read_remote(fd, sizeof(buffer), buffer) != 3) {
264 syslog(LOG_DEBUG, "smarthost authentification:"
265 " AUTH cram-md5 not available: %s", neterr);
266 /* if cram-md5 is not available */
267 return (-1);
270 /* skip 3 char status + 1 char space */
271 base64_decode(buffer + 4, temp);
272 hmac_md5(temp, strlen(temp), password, strlen(password), digest);
273 free(temp);
275 ascii_digest[32] = 0;
276 for (i = 0; i < 16; i++) {
277 ascii_digest[2*i] = hextab[digest[i] >> 4];
278 ascii_digest[2*i+1] = hextab[digest[i] & 15];
281 /* prepare answer */
282 snprintf(buffer, BUF_SIZE, "%s %s", login, ascii_digest);
284 /* encode answer */
285 len = base64_encode(buffer, strlen(buffer), &temp);
286 if (len < 0) {
287 syslog(LOG_ERR, "can not encode auth reply: %m");
288 return (-1);
291 /* send answer */
292 send_remote_command(fd, "%s", temp);
293 free(temp);
294 if (read_remote(fd, 0, NULL) != 2) {
295 syslog(LOG_WARNING, "remote delivery deferred:"
296 " AUTH cram-md5 failed: %s", neterr);
297 return (-2);
300 return (0);