1 /* crypto/rsa/rsa_gen.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
60 /* NB: these functions have been "upgraded", the deprecated versions (which are
61 * compatibility wrappers using these functions) are in rsa_depr.c.
70 #include <openssl/bn.h>
71 #include <openssl/rsa.h>
73 static int rsa_builtin_keygen(RSA *rsa, int bits, BIGNUM *e_value, BN_GENCB *cb);
75 /* NB: this wrapper would normally be placed in rsa_lib.c and the static
76 * implementation would probably be in rsa_eay.c. Nonetheless, is kept here so
77 * that we don't introduce a new linker dependency. Eg. any application that
78 * wasn't previously linking object code related to key-generation won't have to
79 * now just because key-generation is part of RSA_METHOD. */
80 int RSA_generate_key_ex(RSA *rsa, int bits, BIGNUM *e_value, BN_GENCB *cb)
82 if(rsa->meth->rsa_keygen)
83 return rsa->meth->rsa_keygen(rsa, bits, e_value, cb);
84 return rsa_builtin_keygen(rsa, bits, e_value, cb);
87 static int rsa_builtin_keygen(RSA *rsa, int bits, BIGNUM *e_value, BN_GENCB *cb)
89 BIGNUM *r0=NULL,*r1=NULL,*r2=NULL,*r3=NULL,*tmp;
90 BIGNUM *local_r0, *local_d, *local_p;
92 int bitsp,bitsq,ok= -1,n=0;
98 if(!local_r0 || !local_d || !local_p)
102 if (ctx == NULL) goto err;
104 r0 = BN_CTX_get(ctx);
105 r1 = BN_CTX_get(ctx);
106 r2 = BN_CTX_get(ctx);
107 r3 = BN_CTX_get(ctx);
108 if (r3 == NULL) goto err;
113 /* We need the RSA components non-NULL */
114 if(!rsa->n && ((rsa->n=BN_new()) == NULL)) goto err;
115 if(!rsa->d && ((rsa->d=BN_new()) == NULL)) goto err;
116 if(!rsa->e && ((rsa->e=BN_new()) == NULL)) goto err;
117 if(!rsa->p && ((rsa->p=BN_new()) == NULL)) goto err;
118 if(!rsa->q && ((rsa->q=BN_new()) == NULL)) goto err;
119 if(!rsa->dmp1 && ((rsa->dmp1=BN_new()) == NULL)) goto err;
120 if(!rsa->dmq1 && ((rsa->dmq1=BN_new()) == NULL)) goto err;
121 if(!rsa->iqmp && ((rsa->iqmp=BN_new()) == NULL)) goto err;
123 BN_copy(rsa->e, e_value);
125 /* generate p and q */
128 if(!BN_generate_prime_ex(rsa->p, bitsp, 0, NULL, NULL, cb))
130 if (!BN_sub(r2,rsa->p,BN_value_one())) goto err;
131 if (!BN_gcd(r1,r2,rsa->e,ctx)) goto err;
132 if (BN_is_one(r1)) break;
133 if(!BN_GENCB_call(cb, 2, n++))
136 if(!BN_GENCB_call(cb, 3, 0))
140 /* When generating ridiculously small keys, we can get stuck
141 * continually regenerating the same prime values. Check for
142 * this and bail if it happens 3 times. */
143 unsigned int degenerate = 0;
146 if(!BN_generate_prime_ex(rsa->q, bitsq, 0, NULL, NULL, cb))
148 } while((BN_cmp(rsa->p, rsa->q) == 0) && (++degenerate < 3));
151 ok = 0; /* we set our own err */
152 RSAerr(RSA_F_RSA_BUILTIN_KEYGEN,RSA_R_KEY_SIZE_TOO_SMALL);
155 if (!BN_sub(r2,rsa->q,BN_value_one())) goto err;
156 if (!BN_gcd(r1,r2,rsa->e,ctx)) goto err;
159 if(!BN_GENCB_call(cb, 2, n++))
162 if(!BN_GENCB_call(cb, 3, 1))
164 if (BN_cmp(rsa->p,rsa->q) < 0)
172 if (!BN_mul(rsa->n,rsa->p,rsa->q,ctx)) goto err;
175 if (!BN_sub(r1,rsa->p,BN_value_one())) goto err; /* p-1 */
176 if (!BN_sub(r2,rsa->q,BN_value_one())) goto err; /* q-1 */
177 if (!BN_mul(r0,r1,r2,ctx)) goto err; /* (p-1)(q-1) */
178 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
181 BN_with_flags(pr0, r0, BN_FLG_CONSTTIME);
185 if (!BN_mod_inverse(rsa->d,rsa->e,pr0,ctx)) goto err; /* d */
187 /* set up d for correct BN_FLG_CONSTTIME flag */
188 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
191 BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
196 /* calculate d mod (p-1) */
197 if (!BN_mod(rsa->dmp1,d,r1,ctx)) goto err;
199 /* calculate d mod (q-1) */
200 if (!BN_mod(rsa->dmq1,d,r2,ctx)) goto err;
202 /* calculate inverse of q mod p */
203 if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
206 BN_with_flags(p, rsa->p, BN_FLG_CONSTTIME);
210 if (!BN_mod_inverse(rsa->iqmp,rsa->q,p,ctx)) goto err;
214 if(local_r0) BN_free(local_r0);
215 if(local_d) BN_free(local_d);
216 if(local_p) BN_free(local_p);
219 RSAerr(RSA_F_RSA_BUILTIN_KEYGEN,ERR_LIB_BN);