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.
30 * $FreeBSD: src/secure/lib/libcrypt/crypt-blowfish.c,v 1.1.2.1 2001/05/24 12:20:03 markm Exp $
31 * $DragonFly: src/secure/lib/libcrypt/crypt-blowfish.c,v 1.3 2003/11/14 03:54:32 dillon Exp $
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>
59 #include <sys/types.h>
64 /* This implementation is adaptable to current computing power.
65 * You can have up to 2^31 rounds which should be enough for some
69 #define BCRYPT_VERSION '2'
70 #define BCRYPT_MAXSALT 16 /* Precomputation is just so nice */
71 #define BCRYPT_BLOCKS 6 /* Ciphertext blocks */
72 #define BCRYPT_MINROUNDS 16 /* we have log2(rounds) in salt */
74 char *bcrypt_gensalt (u_int8_t
);
76 static void encode_salt (char *, u_int8_t
*, u_int16_t
, u_int8_t
);
77 static void encode_base64 (u_int8_t
*, u_int8_t
*, u_int16_t
);
78 static void decode_base64 (u_int8_t
*, u_int16_t
, u_int8_t
*);
80 static char encrypted
[_PASSWORD_LEN
];
81 static char gsalt
[BCRYPT_MAXSALT
* 4 / 3 + 1];
82 static char error
[] = ":";
84 const static u_int8_t Base64Code
[] =
85 "./ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
87 const static u_int8_t index_64
[128] =
89 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
90 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
91 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
92 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
93 255, 255, 255, 255, 255, 255, 0, 1, 54, 55,
94 56, 57, 58, 59, 60, 61, 62, 63, 255, 255,
95 255, 255, 255, 255, 255, 2, 3, 4, 5, 6,
96 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,
97 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,
98 255, 255, 255, 255, 255, 255, 28, 29, 30,
99 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
100 41, 42, 43, 44, 45, 46, 47, 48, 49, 50,
101 51, 52, 53, 255, 255, 255, 255, 255
103 #define CHAR64(c) ( (c) > 127 ? 255 : index_64[(c)])
107 decode_base64(u_int8_t
*buffer
, u_int16_t len
, u_int8_t
*data
)
110 decode_base64(buffer
, len
, data
)
116 u_int8_t
*bp
= buffer
;
118 u_int8_t c1
, c2
, c3
, c4
;
119 while (bp
< buffer
+ len
) {
121 c2
= CHAR64(*(p
+ 1));
124 if (c1
== 255 || c2
== 255)
127 *bp
++ = (c1
<< 2) | ((c2
& 0x30) >> 4);
128 if (bp
>= buffer
+ len
)
131 c3
= CHAR64(*(p
+ 2));
135 *bp
++ = ((c2
& 0x0f) << 4) | ((c3
& 0x3c) >> 2);
136 if (bp
>= buffer
+ len
)
139 c4
= CHAR64(*(p
+ 3));
142 *bp
++ = ((c3
& 0x03) << 6) | c4
;
150 encode_salt(char *salt
, u_int8_t
*csalt
, u_int16_t clen
, u_int8_t logr
)
153 encode_salt(salt
, csalt
, clen
, logr
)
161 salt
[1] = BCRYPT_VERSION
;
165 snprintf(salt
+ 4, 4, "%2.2u$", logr
);
167 encode_base64((u_int8_t
*) salt
+ 7, csalt
, clen
);
169 /* Generates a salt for this version of crypt.
170 Since versions may change. Keeping this here
176 bcrypt_gensalt(u_int8_t log_rounds
)
179 bcrypt_gensalt(log_rounds
)
183 u_int8_t csalt
[BCRYPT_MAXSALT
];
187 for (i
= 0; i
< BCRYPT_MAXSALT
; i
++) {
190 csalt
[i
] = seed
& 0xff;
197 encode_salt(gsalt
, csalt
, BCRYPT_MAXSALT
, log_rounds
);
200 /* We handle $Vers$log2(NumRounds)$salt+passwd$
201 i.e. $2$04$iwouldntknowwhattosayetKdJ6iFtacBqJdKe6aW7ou */
204 crypt_blowfish(key
, salt
)
209 u_int32_t rounds
, i
, k
;
211 u_int8_t key_len
, salt_len
, logr
, minor
;
212 u_int8_t ciphertext
[4 * BCRYPT_BLOCKS
] = "OrpheanBeholderScryDoubt";
213 u_int8_t csalt
[BCRYPT_MAXSALT
];
214 u_int32_t cdata
[BCRYPT_BLOCKS
];
215 static char *magic
= "$2a$04$";
222 /* If it starts with the magic string, then skip that */
223 if(!strncmp(salt
, magic
, strlen(magic
))) {
224 salt
+= strlen(magic
);
226 else if (*salt
== '$') {
228 /* Discard "$" identifier */
231 if (*salt
> BCRYPT_VERSION
) {
232 /* How do I handle errors ? Return ':' */
236 /* Check for minor versions */
237 if (salt
[1] != '$') {
240 /* 'ab' should not yield the same as 'abab' */
250 /* Discard version + "$" identifier */
254 /* Out of sync with passwd entry */
257 /* Computer power doesnt increase linear, 2^x should be fine */
258 if ((rounds
= (u_int32_t
) 1 << (logr
= atoi(salt
))) < BCRYPT_MINROUNDS
)
261 /* Discard num rounds + "$" identifier */
266 /* We dont want the base64 salt but the raw data */
267 decode_base64(csalt
, BCRYPT_MAXSALT
, (u_int8_t
*) salt
);
268 salt_len
= BCRYPT_MAXSALT
;
269 key_len
= strlen(key
) + (minor
>= 'a' ? 1 : 0);
271 /* Setting up S-Boxes and Subkeys */
272 Blowfish_initstate(&state
);
273 Blowfish_expandstate(&state
, csalt
, salt_len
,
274 (u_int8_t
*) key
, key_len
);
275 for (k
= 0; k
< rounds
; k
++) {
276 Blowfish_expand0state(&state
, (u_int8_t
*) key
, key_len
);
277 Blowfish_expand0state(&state
, csalt
, salt_len
);
280 /* This can be precomputed later */
282 for (i
= 0; i
< BCRYPT_BLOCKS
; i
++)
283 cdata
[i
] = Blowfish_stream2word(ciphertext
, 4 * BCRYPT_BLOCKS
, &j
);
285 /* Now do the encryption */
286 for (k
= 0; k
< 64; k
++)
287 blf_enc(&state
, cdata
, BCRYPT_BLOCKS
/ 2);
289 for (i
= 0; i
< BCRYPT_BLOCKS
; i
++) {
290 ciphertext
[4 * i
+ 3] = cdata
[i
] & 0xff;
291 cdata
[i
] = cdata
[i
] >> 8;
292 ciphertext
[4 * i
+ 2] = cdata
[i
] & 0xff;
293 cdata
[i
] = cdata
[i
] >> 8;
294 ciphertext
[4 * i
+ 1] = cdata
[i
] & 0xff;
295 cdata
[i
] = cdata
[i
] >> 8;
296 ciphertext
[4 * i
+ 0] = cdata
[i
] & 0xff;
301 encrypted
[i
++] = '$';
302 encrypted
[i
++] = BCRYPT_VERSION
;
304 encrypted
[i
++] = minor
;
305 encrypted
[i
++] = '$';
307 snprintf(encrypted
+ i
, 4, "%2.2u$", logr
);
309 encode_base64((u_int8_t
*) encrypted
+ i
+ 3, csalt
, BCRYPT_MAXSALT
);
310 encode_base64((u_int8_t
*) encrypted
+ strlen(encrypted
), ciphertext
,
311 4 * BCRYPT_BLOCKS
- 1);
317 encode_base64(u_int8_t
*buffer
, u_int8_t
*data
, u_int16_t len
)
320 encode_base64(buffer
, data
, len
)
326 u_int8_t
*bp
= buffer
;
329 while (p
< data
+ len
) {
331 *bp
++ = Base64Code
[(c1
>> 2)];
332 c1
= (c1
& 0x03) << 4;
333 if (p
>= data
+ len
) {
334 *bp
++ = Base64Code
[c1
];
338 c1
|= (c2
>> 4) & 0x0f;
339 *bp
++ = Base64Code
[c1
];
340 c1
= (c2
& 0x0f) << 2;
341 if (p
>= data
+ len
) {
342 *bp
++ = Base64Code
[c1
];
346 c1
|= (c2
>> 6) & 0x03;
347 *bp
++ = Base64Code
[c1
];
348 *bp
++ = Base64Code
[c2
& 0x3f];
360 salt
[1] = BCRYPT_VERSION
;
363 snprintf(salt
+ 3, 4, "%2.2u$", 5);
365 printf("24 bytes of salt: ");
366 fgets(salt
+ 6, 94, stdin
);
368 printf("72 bytes of password: ");
370 fgets(blubber
, 73, stdin
);
373 p
= crypt(blubber
, salt
);
374 printf("Passwd entry: %s\n\n", p
);
376 p
= bcrypt_gensalt(5);
377 printf("Generated salt: %s\n", p
);
378 p
= crypt(blubber
, p
);
379 printf("Passwd entry: %s\n", p
);