2 * Written by Christophe Renou (christophe.renou@edelweb.fr) with the
3 * precious help of Peter Sylvester (peter.sylvester@edelweb.fr) for the
4 * EdelKey project and contributed to the OpenSSL project 2004.
6 /* ====================================================================
7 * Copyright (c) 2004 The OpenSSL Project. All rights reserved.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in
18 * the documentation and/or other materials provided with the
21 * 3. All advertising materials mentioning features or use of this
22 * software must display the following acknowledgment:
23 * "This product includes software developed by the OpenSSL Project
24 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27 * endorse or promote products derived from this software without
28 * prior written permission. For written permission, please contact
29 * licensing@OpenSSL.org.
31 * 5. Products derived from this software may not be called "OpenSSL"
32 * nor may "OpenSSL" appear in their names without prior written
33 * permission of the OpenSSL Project.
35 * 6. Redistributions of any form whatsoever must retain the following
37 * "This product includes software developed by the OpenSSL Project
38 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51 * OF THE POSSIBILITY OF SUCH DAMAGE.
52 * ====================================================================
54 * This product includes cryptographic software written by Eric Young
55 * (eay@cryptsoft.com). This product includes software written by Tim
56 * Hudson (tjh@cryptsoft.com).
59 #ifndef OPENSSL_NO_SRP
60 # include "internal/cryptlib.h"
61 # include <openssl/sha.h>
62 # include <openssl/srp.h>
63 # include <openssl/evp.h>
64 # include <openssl/buffer.h>
65 # include <openssl/rand.h>
66 # include <openssl/txt_db.h>
68 # define SRP_RANDOM_SALT_LEN 20
71 static char b64table
[] =
72 "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz./";
75 * the following two conversion routines have been inspired by code from
80 * Convert a base64 string into raw byte array representation.
82 static int t_fromb64(unsigned char *a
, const char *src
)
88 while (*src
&& (*src
== ' ' || *src
== '\t' || *src
== '\n'))
93 loc
= strchr(b64table
, src
[i
]);
97 a
[i
] = loc
- b64table
;
100 /* if nothing valid to process we have a zero length response */
110 a
[j
] |= (a
[i
] & 3) << 6;
112 a
[j
] = (unsigned char)((a
[i
] & 0x3c) >> 2);
115 a
[j
] |= (a
[i
] & 0xf) << 4;
117 a
[j
] = (unsigned char)((a
[i
] & 0x30) >> 4);
126 while (a
[j
] == 0 && j
<= size
)
135 * Convert a raw byte string into a null-terminated base64 ASCII string.
137 static char *t_tob64(char *dst
, const unsigned char *src
, int size
)
139 int c
, pos
= size
% 3;
140 unsigned char b0
= 0, b1
= 0, b2
= 0, notleading
= 0;
154 c
= (b0
& 0xfc) >> 2;
155 if (notleading
|| c
!= 0) {
156 *dst
++ = b64table
[c
];
159 c
= ((b0
& 3) << 4) | ((b1
& 0xf0) >> 4);
160 if (notleading
|| c
!= 0) {
161 *dst
++ = b64table
[c
];
164 c
= ((b1
& 0xf) << 2) | ((b2
& 0xc0) >> 6);
165 if (notleading
|| c
!= 0) {
166 *dst
++ = b64table
[c
];
170 if (notleading
|| c
!= 0) {
171 *dst
++ = b64table
[c
];
187 void SRP_user_pwd_free(SRP_user_pwd
*user_pwd
)
189 if (user_pwd
== NULL
)
191 BN_free(user_pwd
->s
);
192 BN_clear_free(user_pwd
->v
);
193 OPENSSL_free(user_pwd
->id
);
194 OPENSSL_free(user_pwd
->info
);
195 OPENSSL_free(user_pwd
);
198 static SRP_user_pwd
*SRP_user_pwd_new(void)
200 SRP_user_pwd
*ret
= OPENSSL_malloc(sizeof(*ret
));
212 static void SRP_user_pwd_set_gN(SRP_user_pwd
*vinfo
, const BIGNUM
*g
,
219 static int SRP_user_pwd_set_ids(SRP_user_pwd
*vinfo
, const char *id
,
222 if (id
!= NULL
&& NULL
== (vinfo
->id
= OPENSSL_strdup(id
)))
224 return (info
== NULL
|| NULL
!= (vinfo
->info
= OPENSSL_strdup(info
)));
227 static int SRP_user_pwd_set_sv(SRP_user_pwd
*vinfo
, const char *s
,
230 unsigned char tmp
[MAX_LEN
];
233 if (strlen(s
) > MAX_LEN
|| strlen(v
) > MAX_LEN
)
235 len
= t_fromb64(tmp
, v
);
236 if (NULL
== (vinfo
->v
= BN_bin2bn(tmp
, len
, NULL
)))
238 len
= t_fromb64(tmp
, s
);
239 return ((vinfo
->s
= BN_bin2bn(tmp
, len
, NULL
)) != NULL
);
242 static int SRP_user_pwd_set_sv_BN(SRP_user_pwd
*vinfo
, BIGNUM
*s
, BIGNUM
*v
)
246 return (vinfo
->s
!= NULL
&& vinfo
->v
!= NULL
);
249 static SRP_user_pwd
*srp_user_pwd_dup(SRP_user_pwd
*src
)
255 if ((ret
= SRP_user_pwd_new()) == NULL
)
258 SRP_user_pwd_set_gN(ret
, src
->g
, src
->N
);
259 if (!SRP_user_pwd_set_ids(ret
, src
->id
, src
->info
)
260 || !SRP_user_pwd_set_sv_BN(ret
, BN_dup(src
->s
), BN_dup(src
->v
))) {
261 SRP_user_pwd_free(ret
);
267 SRP_VBASE
*SRP_VBASE_new(char *seed_key
)
269 SRP_VBASE
*vb
= OPENSSL_malloc(sizeof(*vb
));
273 if ((vb
->users_pwd
= sk_SRP_user_pwd_new_null()) == NULL
274 || (vb
->gN_cache
= sk_SRP_gN_cache_new_null()) == NULL
) {
278 vb
->default_g
= NULL
;
279 vb
->default_N
= NULL
;
281 if ((seed_key
!= NULL
) && (vb
->seed_key
= OPENSSL_strdup(seed_key
)) == NULL
) {
282 sk_SRP_user_pwd_free(vb
->users_pwd
);
283 sk_SRP_gN_cache_free(vb
->gN_cache
);
290 void SRP_VBASE_free(SRP_VBASE
*vb
)
294 sk_SRP_user_pwd_pop_free(vb
->users_pwd
, SRP_user_pwd_free
);
295 sk_SRP_gN_cache_free(vb
->gN_cache
);
296 OPENSSL_free(vb
->seed_key
);
300 static SRP_gN_cache
*SRP_gN_new_init(const char *ch
)
302 unsigned char tmp
[MAX_LEN
];
304 SRP_gN_cache
*newgN
= OPENSSL_malloc(sizeof(*newgN
));
309 if ((newgN
->b64_bn
= OPENSSL_strdup(ch
)) == NULL
)
312 len
= t_fromb64(tmp
, ch
);
313 if ((newgN
->bn
= BN_bin2bn(tmp
, len
, NULL
)))
316 OPENSSL_free(newgN
->b64_bn
);
322 static void SRP_gN_free(SRP_gN_cache
*gN_cache
)
324 if (gN_cache
== NULL
)
326 OPENSSL_free(gN_cache
->b64_bn
);
327 BN_free(gN_cache
->bn
);
328 OPENSSL_free(gN_cache
);
331 static SRP_gN
*SRP_get_gN_by_id(const char *id
, STACK_OF(SRP_gN
) *gN_tab
)
337 for (i
= 0; i
< sk_SRP_gN_num(gN_tab
); i
++) {
338 gN
= sk_SRP_gN_value(gN_tab
, i
);
339 if (gN
&& (id
== NULL
|| strcmp(gN
->id
, id
) == 0))
343 return SRP_get_default_gN(id
);
346 static BIGNUM
*SRP_gN_place_bn(STACK_OF(SRP_gN_cache
) *gN_cache
, char *ch
)
349 if (gN_cache
== NULL
)
352 /* search if we have already one... */
353 for (i
= 0; i
< sk_SRP_gN_cache_num(gN_cache
); i
++) {
354 SRP_gN_cache
*cache
= sk_SRP_gN_cache_value(gN_cache
, i
);
355 if (strcmp(cache
->b64_bn
, ch
) == 0)
358 { /* it is the first time that we find it */
359 SRP_gN_cache
*newgN
= SRP_gN_new_init(ch
);
361 if (sk_SRP_gN_cache_insert(gN_cache
, newgN
, 0) > 0)
370 * this function parses verifier file. Format is:
371 * string(index):base64(N):base64(g):0
372 * string(username):base64(v):base64(salt):int(index)
375 int SRP_VBASE_init(SRP_VBASE
*vb
, char *verifier_file
)
378 STACK_OF(SRP_gN
) *SRP_gN_tab
= sk_SRP_gN_new_null();
379 char *last_index
= NULL
;
384 SRP_user_pwd
*user_pwd
= NULL
;
386 TXT_DB
*tmpdb
= NULL
;
387 BIO
*in
= BIO_new(BIO_s_file());
389 error_code
= SRP_ERR_OPEN_FILE
;
391 if (in
== NULL
|| BIO_read_filename(in
, verifier_file
) <= 0)
394 error_code
= SRP_ERR_VBASE_INCOMPLETE_FILE
;
396 if ((tmpdb
= TXT_DB_read(in
, DB_NUMBER
)) == NULL
)
399 error_code
= SRP_ERR_MEMORY
;
402 last_index
= SRP_get_default_gN(NULL
)->id
;
404 for (i
= 0; i
< sk_OPENSSL_PSTRING_num(tmpdb
->data
); i
++) {
405 pp
= sk_OPENSSL_PSTRING_value(tmpdb
->data
, i
);
406 if (pp
[DB_srptype
][0] == DB_SRP_INDEX
) {
408 * we add this couple in the internal Stack
411 if ((gN
= OPENSSL_malloc(sizeof(*gN
))) == NULL
)
414 if ((gN
->id
= OPENSSL_strdup(pp
[DB_srpid
])) == NULL
415 || (gN
->N
= SRP_gN_place_bn(vb
->gN_cache
, pp
[DB_srpverifier
]))
417 || (gN
->g
= SRP_gN_place_bn(vb
->gN_cache
, pp
[DB_srpsalt
]))
419 || sk_SRP_gN_insert(SRP_gN_tab
, gN
, 0) == 0)
424 if (vb
->seed_key
!= NULL
) {
425 last_index
= pp
[DB_srpid
];
427 } else if (pp
[DB_srptype
][0] == DB_SRP_VALID
) {
428 /* it is a user .... */
431 if ((lgN
= SRP_get_gN_by_id(pp
[DB_srpgN
], SRP_gN_tab
)) != NULL
) {
432 error_code
= SRP_ERR_MEMORY
;
433 if ((user_pwd
= SRP_user_pwd_new()) == NULL
)
436 SRP_user_pwd_set_gN(user_pwd
, lgN
->g
, lgN
->N
);
437 if (!SRP_user_pwd_set_ids
438 (user_pwd
, pp
[DB_srpid
], pp
[DB_srpinfo
]))
441 error_code
= SRP_ERR_VBASE_BN_LIB
;
442 if (!SRP_user_pwd_set_sv
443 (user_pwd
, pp
[DB_srpsalt
], pp
[DB_srpverifier
]))
446 if (sk_SRP_user_pwd_insert(vb
->users_pwd
, user_pwd
, 0) == 0)
448 user_pwd
= NULL
; /* abandon responsibility */
453 if (last_index
!= NULL
) {
454 /* this means that we want to simulate a default user */
456 if (((gN
= SRP_get_gN_by_id(last_index
, SRP_gN_tab
)) == NULL
)) {
457 error_code
= SRP_ERR_VBASE_BN_LIB
;
460 vb
->default_g
= gN
->g
;
461 vb
->default_N
= gN
->N
;
464 error_code
= SRP_NO_ERROR
;
468 * there may be still some leaks to fix, if this fails, the application
469 * terminates most likely
473 OPENSSL_free(gN
->id
);
477 SRP_user_pwd_free(user_pwd
);
482 sk_SRP_gN_free(SRP_gN_tab
);
488 static SRP_user_pwd
*find_user(SRP_VBASE
*vb
, char *username
)
496 for (i
= 0; i
< sk_SRP_user_pwd_num(vb
->users_pwd
); i
++) {
497 user
= sk_SRP_user_pwd_value(vb
->users_pwd
, i
);
498 if (strcmp(user
->id
, username
) == 0)
505 #if OPENSSL_API_COMPAT < 0x10100000L
507 * DEPRECATED: use SRP_VBASE_get1_by_user instead.
508 * This method ignores the configured seed and fails for an unknown user.
509 * Ownership of the returned pointer is not released to the caller.
510 * In other words, caller must not free the result.
512 SRP_user_pwd
*SRP_VBASE_get_by_user(SRP_VBASE
*vb
, char *username
)
514 return find_user(vb
, username
);
519 * Ownership of the returned pointer is released to the caller.
520 * In other words, caller must free the result once done.
522 SRP_user_pwd
*SRP_VBASE_get1_by_user(SRP_VBASE
*vb
, char *username
)
525 unsigned char digv
[SHA_DIGEST_LENGTH
];
526 unsigned char digs
[SHA_DIGEST_LENGTH
];
527 EVP_MD_CTX
*ctxt
= NULL
;
532 if ((user
= find_user(vb
, username
)) != NULL
)
533 return srp_user_pwd_dup(user
);
535 if ((vb
->seed_key
== NULL
) ||
536 (vb
->default_g
== NULL
) || (vb
->default_N
== NULL
))
539 /* if the user is unknown we set parameters as well if we have a seed_key */
541 if ((user
= SRP_user_pwd_new()) == NULL
)
544 SRP_user_pwd_set_gN(user
, vb
->default_g
, vb
->default_N
);
546 if (!SRP_user_pwd_set_ids(user
, username
, NULL
))
549 if (RAND_bytes(digv
, SHA_DIGEST_LENGTH
) <= 0)
551 ctxt
= EVP_MD_CTX_new();
552 EVP_DigestInit_ex(ctxt
, EVP_sha1(), NULL
);
553 EVP_DigestUpdate(ctxt
, vb
->seed_key
, strlen(vb
->seed_key
));
554 EVP_DigestUpdate(ctxt
, username
, strlen(username
));
555 EVP_DigestFinal_ex(ctxt
, digs
, NULL
);
556 EVP_MD_CTX_free(ctxt
);
558 if (SRP_user_pwd_set_sv_BN(user
,
559 BN_bin2bn(digs
, SHA_DIGEST_LENGTH
, NULL
),
560 BN_bin2bn(digv
, SHA_DIGEST_LENGTH
, NULL
)))
564 EVP_MD_CTX_free(ctxt
);
565 SRP_user_pwd_free(user
);
570 * create a verifier (*salt,*verifier,g and N are in base64)
572 char *SRP_create_verifier(const char *user
, const char *pass
, char **salt
,
573 char **verifier
, const char *N
, const char *g
)
576 char *result
= NULL
, *vf
= NULL
;
577 BIGNUM
*N_bn
= NULL
, *g_bn
= NULL
, *s
= NULL
, *v
= NULL
;
578 unsigned char tmp
[MAX_LEN
];
579 unsigned char tmp2
[MAX_LEN
];
580 char *defgNid
= NULL
;
583 if ((user
== NULL
) ||
584 (pass
== NULL
) || (salt
== NULL
) || (verifier
== NULL
))
588 if ((len
= t_fromb64(tmp
, N
)) == 0)
590 N_bn
= BN_bin2bn(tmp
, len
, NULL
);
591 if ((len
= t_fromb64(tmp
, g
)) == 0)
593 g_bn
= BN_bin2bn(tmp
, len
, NULL
);
596 SRP_gN
*gN
= SRP_get_gN_by_id(g
, NULL
);
605 if (RAND_bytes(tmp2
, SRP_RANDOM_SALT_LEN
) <= 0)
608 s
= BN_bin2bn(tmp2
, SRP_RANDOM_SALT_LEN
, NULL
);
610 if ((len
= t_fromb64(tmp2
, *salt
)) == 0)
612 s
= BN_bin2bn(tmp2
, len
, NULL
);
615 if (!SRP_create_verifier_BN(user
, pass
, &s
, &v
, N_bn
, g_bn
))
619 vfsize
= BN_num_bytes(v
) * 2;
620 if (((vf
= OPENSSL_malloc(vfsize
)) == NULL
))
622 t_tob64(vf
, tmp
, BN_num_bytes(v
));
627 if ((tmp_salt
= OPENSSL_malloc(SRP_RANDOM_SALT_LEN
* 2)) == NULL
) {
630 t_tob64(tmp_salt
, tmp2
, SRP_RANDOM_SALT_LEN
);
643 OPENSSL_clear_free(vf
, vfsize
);
650 * create a verifier (*salt,*verifier,g and N are BIGNUMs). If *salt != NULL
651 * then the provided salt will be used. On successful exit *verifier will point
652 * to a newly allocated BIGNUM containing the verifier and (if a salt was not
653 * provided) *salt will be populated with a newly allocated BIGNUM containing a
655 * The caller is responsible for freeing the allocated *salt and *verifier
658 int SRP_create_verifier_BN(const char *user
, const char *pass
, BIGNUM
**salt
,
659 BIGNUM
**verifier
, const BIGNUM
*N
,
664 BN_CTX
*bn_ctx
= BN_CTX_new();
665 unsigned char tmp2
[MAX_LEN
];
666 BIGNUM
*salttmp
= NULL
;
668 if ((user
== NULL
) ||
671 (verifier
== NULL
) || (N
== NULL
) || (g
== NULL
) || (bn_ctx
== NULL
))
675 if (RAND_bytes(tmp2
, SRP_RANDOM_SALT_LEN
) <= 0)
678 salttmp
= BN_bin2bn(tmp2
, SRP_RANDOM_SALT_LEN
, NULL
);
683 x
= SRP_Calc_x(salttmp
, user
, pass
);
685 *verifier
= BN_new();
686 if (*verifier
== NULL
)
689 if (!BN_mod_exp(*verifier
, g
, x
, N
, bn_ctx
)) {
690 BN_clear_free(*verifier
);
698 if (salt
!= NULL
&& *salt
!= salttmp
)
699 BN_clear_free(salttmp
);