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);