2 * Copyright 1997 Niels Provos <provos@physnet.uni-hamburg.de>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by Niels Provos.
16 * 4. The name of the author may not be used to endorse or promote products
17 * derived from this software without specific prior written permission.
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
34 /* This password hashing algorithm was designed by David Mazieres
35 * <dm@lcs.mit.edu> and works as follows:
37 * 1. state := InitState ()
38 * 2. state := ExpandKey (state, salt, password) 3.
40 * state := ExpandKey (state, 0, salt)
41 * state := ExpandKey(state, 0, password)
42 * 4. ctext := "OrpheanBeholderScryDoubt"
44 * ctext := Encrypt_ECB (state, ctext);
45 * 6. RETURN Concatenate (salt, ctext);
50 * FreeBSD implementation by Paul Herman <pherman@frenchfries.net>
55 #include <sys/types.h>
61 /* This implementation is adaptable to current computing power.
62 * You can have up to 2^31 rounds which should be enough for some
66 #define BCRYPT_VERSION '2'
67 #define BCRYPT_MAXSALT 16 /* Precomputation is just so nice */
68 #define BCRYPT_BLOCKS 6 /* Ciphertext blocks */
69 #define BCRYPT_MINROUNDS 16 /* we have log2(rounds) in salt */
71 static void encode_base64(u_int8_t *, u_int8_t *, u_int16_t);
72 static void decode_base64(u_int8_t *, u_int16_t, const u_int8_t *);
74 static char encrypted[_PASSWORD_LEN];
76 static const u_int8_t Base64Code[] =
77 "./ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
79 static const u_int8_t index_64[128] =
81 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
82 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
83 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
84 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
85 255, 255, 255, 255, 255, 255, 0, 1, 54, 55,
86 56, 57, 58, 59, 60, 61, 62, 63, 255, 255,
87 255, 255, 255, 255, 255, 2, 3, 4, 5, 6,
88 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,
89 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,
90 255, 255, 255, 255, 255, 255, 28, 29, 30,
91 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
92 41, 42, 43, 44, 45, 46, 47, 48, 49, 50,
93 51, 52, 53, 255, 255, 255, 255, 255
95 #define CHAR64(c) ( (c) > 127 ? 255 : index_64[(c)])
98 decode_base64(u_int8_t *buffer, u_int16_t len, const u_int8_t *data)
100 u_int8_t *bp = buffer;
101 const u_int8_t *p = data;
102 u_int8_t c1, c2, c3, c4;
103 while (bp < buffer + len) {
105 c2 = CHAR64(*(p + 1));
108 if (c1 == 255 || c2 == 255)
111 *bp++ = (u_int8_t)((c1 << 2) | ((c2 & 0x30) >> 4));
112 if (bp >= buffer + len)
115 c3 = CHAR64(*(p + 2));
119 *bp++ = ((c2 & 0x0f) << 4) | ((c3 & 0x3c) >> 2);
120 if (bp >= buffer + len)
123 c4 = CHAR64(*(p + 3));
126 *bp++ = ((c3 & 0x03) << 6) | c4;
132 /* We handle $Vers$log2(NumRounds)$salt+passwd$
133 i.e. $2$04$iwouldntknowwhattosayetKdJ6iFtacBqJdKe6aW7ou */
136 crypt_blowfish(const char *key, const char *salt)
139 u_int32_t rounds, i, k;
141 u_int8_t key_len, salt_len, logr, minr;
142 u_int8_t ciphertext[4 * BCRYPT_BLOCKS] = "OrpheanBeholderScryDoubt";
143 u_int8_t csalt[BCRYPT_MAXSALT];
144 u_int32_t cdata[BCRYPT_BLOCKS];
145 static const char *magic = "$2a$04$";
152 /* If it starts with the magic string, then skip that */
153 if(!strncmp(salt, magic, strlen(magic))) {
154 salt += strlen(magic);
156 else if (*salt == '$') {
158 /* Discard "$" identifier */
161 if (*salt > BCRYPT_VERSION) {
162 /* How do I handle errors ? Return NULL */
166 /* Check for minor versions */
167 if (salt[1] != '$') {
170 /* 'ab' should not yield the same as 'abab' */
171 minr = (u_int8_t)salt[1];
180 /* Discard version + "$" identifier */
184 /* Out of sync with passwd entry */
187 /* Computer power doesnt increase linear, 2^x should be fine */
188 logr = (u_int8_t)atoi(salt);
190 if (rounds < BCRYPT_MINROUNDS)
193 /* Discard num rounds + "$" identifier */
198 /* We dont want the base64 salt but the raw data */
199 decode_base64(csalt, BCRYPT_MAXSALT, (const u_int8_t *)salt);
200 salt_len = BCRYPT_MAXSALT;
201 key_len = (u_int8_t)(strlen(key) + (minr >= 'a' ? 1 : 0));
203 /* Setting up S-Boxes and Subkeys */
204 Blowfish_initstate(&state);
205 Blowfish_expandstate(&state, csalt, salt_len,
206 (const u_int8_t *) key, key_len);
207 for (k = 0; k < rounds; k++) {
208 Blowfish_expand0state(&state, (const u_int8_t *) key, key_len);
209 Blowfish_expand0state(&state, csalt, salt_len);
212 /* This can be precomputed later */
214 for (i = 0; i < BCRYPT_BLOCKS; i++)
215 cdata[i] = Blowfish_stream2word(ciphertext, 4 * BCRYPT_BLOCKS, &j);
217 /* Now do the encryption */
218 for (k = 0; k < 64; k++)
219 blf_enc(&state, cdata, BCRYPT_BLOCKS / 2);
221 for (i = 0; i < BCRYPT_BLOCKS; i++) {
222 ciphertext[4 * i + 3] = cdata[i] & 0xff;
223 cdata[i] = cdata[i] >> 8;
224 ciphertext[4 * i + 2] = cdata[i] & 0xff;
225 cdata[i] = cdata[i] >> 8;
226 ciphertext[4 * i + 1] = cdata[i] & 0xff;
227 cdata[i] = cdata[i] >> 8;
228 ciphertext[4 * i + 0] = cdata[i] & 0xff;
233 encrypted[i++] = '$';
234 encrypted[i++] = BCRYPT_VERSION;
236 encrypted[i++] = (int8_t)minr;
237 encrypted[i++] = '$';
239 snprintf(encrypted + i, 4, "%2.2u$", logr);
241 encode_base64((u_int8_t *) encrypted + i + 3, csalt, BCRYPT_MAXSALT);
242 encode_base64((u_int8_t *) encrypted + strlen(encrypted), ciphertext,
243 4 * BCRYPT_BLOCKS - 1);
248 encode_base64(u_int8_t *buffer, u_int8_t *data, u_int16_t len)
250 u_int8_t *bp = buffer;
253 while (p < data + len) {
255 *bp++ = Base64Code[(c1 >> 2)];
256 c1 = (c1 & 0x03) << 4;
257 if (p >= data + len) {
258 *bp++ = Base64Code[c1];
262 c1 |= (c2 >> 4) & 0x0f;
263 *bp++ = Base64Code[c1];
264 c1 = (c2 & 0x0f) << 2;
265 if (p >= data + len) {
266 *bp++ = Base64Code[c1];
270 c1 |= (c2 >> 6) & 0x03;
271 *bp++ = Base64Code[c1];
272 *bp++ = Base64Code[c2 & 0x3f];
285 salt[1] = BCRYPT_VERSION;
288 snprintf(salt + 3, 4, "%2.2u$", 5);
290 printf("24 bytes of salt: ");
291 fgets(salt + 6, 94, stdin);
293 printf("72 bytes of password: ");
295 fgets(blubber, 73, stdin);
298 p = crypt(blubber, salt);
299 printf("Passwd entry: %s\n\n", p);
301 p = bcrypt_gensalt(5);
302 printf("Generated salt: %s\n", p);
303 p = crypt(blubber, p);
304 printf("Passwd entry: %s\n", p);