diff options
Diffstat (limited to 'src/lib/libcrypto/dh/dh_key.c')
| -rw-r--r-- | src/lib/libcrypto/dh/dh_key.c | 263 |
1 files changed, 263 insertions, 0 deletions
diff --git a/src/lib/libcrypto/dh/dh_key.c b/src/lib/libcrypto/dh/dh_key.c new file mode 100644 index 0000000000..e7db440342 --- /dev/null +++ b/src/lib/libcrypto/dh/dh_key.c | |||
| @@ -0,0 +1,263 @@ | |||
| 1 | /* crypto/dh/dh_key.c */ | ||
| 2 | /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) | ||
| 3 | * All rights reserved. | ||
| 4 | * | ||
| 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. | ||
| 8 | * | ||
| 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). | ||
| 15 | * | ||
| 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. | ||
| 22 | * | ||
| 23 | * Redistribution and use in source and binary forms, with or without | ||
| 24 | * modification, are permitted provided that the following conditions | ||
| 25 | * are met: | ||
| 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)" | ||
| 40 | * | ||
| 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 | ||
| 51 | * SUCH DAMAGE. | ||
| 52 | * | ||
| 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.] | ||
| 57 | */ | ||
| 58 | |||
| 59 | #include <stdio.h> | ||
| 60 | #include "cryptlib.h" | ||
| 61 | #include <openssl/bn.h> | ||
| 62 | #include <openssl/rand.h> | ||
| 63 | #include <openssl/dh.h> | ||
| 64 | |||
| 65 | static int generate_key(DH *dh); | ||
| 66 | static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh); | ||
| 67 | static int dh_bn_mod_exp(const DH *dh, BIGNUM *r, | ||
| 68 | const BIGNUM *a, const BIGNUM *p, | ||
| 69 | const BIGNUM *m, BN_CTX *ctx, | ||
| 70 | BN_MONT_CTX *m_ctx); | ||
| 71 | static int dh_init(DH *dh); | ||
| 72 | static int dh_finish(DH *dh); | ||
| 73 | |||
| 74 | int DH_generate_key(DH *dh) | ||
| 75 | { | ||
| 76 | return dh->meth->generate_key(dh); | ||
| 77 | } | ||
| 78 | |||
| 79 | int DH_compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh) | ||
| 80 | { | ||
| 81 | return dh->meth->compute_key(key, pub_key, dh); | ||
| 82 | } | ||
| 83 | |||
| 84 | static DH_METHOD dh_ossl = { | ||
| 85 | "OpenSSL DH Method", | ||
| 86 | generate_key, | ||
| 87 | compute_key, | ||
| 88 | dh_bn_mod_exp, | ||
| 89 | dh_init, | ||
| 90 | dh_finish, | ||
| 91 | 0, | ||
| 92 | NULL, | ||
| 93 | NULL | ||
| 94 | }; | ||
| 95 | |||
| 96 | const DH_METHOD *DH_OpenSSL(void) | ||
| 97 | { | ||
| 98 | return &dh_ossl; | ||
| 99 | } | ||
| 100 | |||
| 101 | static int generate_key(DH *dh) | ||
| 102 | { | ||
| 103 | int ok=0; | ||
| 104 | int generate_new_key=0; | ||
| 105 | unsigned l; | ||
| 106 | BN_CTX *ctx; | ||
| 107 | BN_MONT_CTX *mont=NULL; | ||
| 108 | BIGNUM *pub_key=NULL,*priv_key=NULL; | ||
| 109 | |||
| 110 | ctx = BN_CTX_new(); | ||
| 111 | if (ctx == NULL) goto err; | ||
| 112 | |||
| 113 | if (dh->priv_key == NULL) | ||
| 114 | { | ||
| 115 | priv_key=BN_new(); | ||
| 116 | if (priv_key == NULL) goto err; | ||
| 117 | generate_new_key=1; | ||
| 118 | } | ||
| 119 | else | ||
| 120 | priv_key=dh->priv_key; | ||
| 121 | |||
| 122 | if (dh->pub_key == NULL) | ||
| 123 | { | ||
| 124 | pub_key=BN_new(); | ||
| 125 | if (pub_key == NULL) goto err; | ||
| 126 | } | ||
| 127 | else | ||
| 128 | pub_key=dh->pub_key; | ||
| 129 | |||
| 130 | |||
| 131 | if (dh->flags & DH_FLAG_CACHE_MONT_P) | ||
| 132 | { | ||
| 133 | mont = BN_MONT_CTX_set_locked(&dh->method_mont_p, | ||
| 134 | CRYPTO_LOCK_DH, dh->p, ctx); | ||
| 135 | if (!mont) | ||
| 136 | goto err; | ||
| 137 | } | ||
| 138 | |||
| 139 | if (generate_new_key) | ||
| 140 | { | ||
| 141 | l = dh->length ? dh->length : BN_num_bits(dh->p)-1; /* secret exponent length */ | ||
| 142 | if (!BN_rand(priv_key, l, 0, 0)) goto err; | ||
| 143 | } | ||
| 144 | |||
| 145 | { | ||
| 146 | BIGNUM local_prk; | ||
| 147 | BIGNUM *prk; | ||
| 148 | |||
| 149 | if ((dh->flags & DH_FLAG_NO_EXP_CONSTTIME) == 0) | ||
| 150 | { | ||
| 151 | BN_init(&local_prk); | ||
| 152 | prk = &local_prk; | ||
| 153 | BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME); | ||
| 154 | } | ||
| 155 | else | ||
| 156 | prk = priv_key; | ||
| 157 | |||
| 158 | if (!dh->meth->bn_mod_exp(dh, pub_key, dh->g, prk, dh->p, ctx, mont)) goto err; | ||
| 159 | } | ||
| 160 | |||
| 161 | dh->pub_key=pub_key; | ||
| 162 | dh->priv_key=priv_key; | ||
| 163 | ok=1; | ||
| 164 | err: | ||
| 165 | if (ok != 1) | ||
| 166 | DHerr(DH_F_GENERATE_KEY,ERR_R_BN_LIB); | ||
| 167 | |||
| 168 | if ((pub_key != NULL) && (dh->pub_key == NULL)) BN_free(pub_key); | ||
| 169 | if ((priv_key != NULL) && (dh->priv_key == NULL)) BN_free(priv_key); | ||
| 170 | BN_CTX_free(ctx); | ||
| 171 | return(ok); | ||
| 172 | } | ||
| 173 | |||
| 174 | static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh) | ||
| 175 | { | ||
| 176 | BN_CTX *ctx=NULL; | ||
| 177 | BN_MONT_CTX *mont=NULL; | ||
| 178 | BIGNUM *tmp; | ||
| 179 | int ret= -1; | ||
| 180 | int check_result; | ||
| 181 | |||
| 182 | if (BN_num_bits(dh->p) > OPENSSL_DH_MAX_MODULUS_BITS) | ||
| 183 | { | ||
| 184 | DHerr(DH_F_COMPUTE_KEY,DH_R_MODULUS_TOO_LARGE); | ||
| 185 | goto err; | ||
| 186 | } | ||
| 187 | |||
| 188 | ctx = BN_CTX_new(); | ||
| 189 | if (ctx == NULL) goto err; | ||
| 190 | BN_CTX_start(ctx); | ||
| 191 | tmp = BN_CTX_get(ctx); | ||
| 192 | |||
| 193 | if (dh->priv_key == NULL) | ||
| 194 | { | ||
| 195 | DHerr(DH_F_COMPUTE_KEY,DH_R_NO_PRIVATE_VALUE); | ||
| 196 | goto err; | ||
| 197 | } | ||
| 198 | |||
| 199 | if (dh->flags & DH_FLAG_CACHE_MONT_P) | ||
| 200 | { | ||
| 201 | mont = BN_MONT_CTX_set_locked(&dh->method_mont_p, | ||
| 202 | CRYPTO_LOCK_DH, dh->p, ctx); | ||
| 203 | if ((dh->flags & DH_FLAG_NO_EXP_CONSTTIME) == 0) | ||
| 204 | { | ||
| 205 | /* XXX */ | ||
| 206 | BN_set_flags(dh->priv_key, BN_FLG_CONSTTIME); | ||
| 207 | } | ||
| 208 | if (!mont) | ||
| 209 | goto err; | ||
| 210 | } | ||
| 211 | |||
| 212 | if (!DH_check_pub_key(dh, pub_key, &check_result) || check_result) | ||
| 213 | { | ||
| 214 | DHerr(DH_F_COMPUTE_KEY,DH_R_INVALID_PUBKEY); | ||
| 215 | goto err; | ||
| 216 | } | ||
| 217 | |||
| 218 | if (!dh->meth->bn_mod_exp(dh, tmp, pub_key, dh->priv_key,dh->p,ctx,mont)) | ||
| 219 | { | ||
| 220 | DHerr(DH_F_COMPUTE_KEY,ERR_R_BN_LIB); | ||
| 221 | goto err; | ||
| 222 | } | ||
| 223 | |||
| 224 | ret=BN_bn2bin(tmp,key); | ||
| 225 | err: | ||
| 226 | if (ctx != NULL) | ||
| 227 | { | ||
| 228 | BN_CTX_end(ctx); | ||
| 229 | BN_CTX_free(ctx); | ||
| 230 | } | ||
| 231 | return(ret); | ||
| 232 | } | ||
| 233 | |||
| 234 | static int dh_bn_mod_exp(const DH *dh, BIGNUM *r, | ||
| 235 | const BIGNUM *a, const BIGNUM *p, | ||
| 236 | const BIGNUM *m, BN_CTX *ctx, | ||
| 237 | BN_MONT_CTX *m_ctx) | ||
| 238 | { | ||
| 239 | /* If a is only one word long and constant time is false, use the faster | ||
| 240 | * exponenentiation function. | ||
| 241 | */ | ||
| 242 | if (a->top == 1 && ((dh->flags & DH_FLAG_NO_EXP_CONSTTIME) != 0)) | ||
| 243 | { | ||
| 244 | BN_ULONG A = a->d[0]; | ||
| 245 | return BN_mod_exp_mont_word(r,A,p,m,ctx,m_ctx); | ||
| 246 | } | ||
| 247 | else | ||
| 248 | return BN_mod_exp_mont(r,a,p,m,ctx,m_ctx); | ||
| 249 | } | ||
| 250 | |||
| 251 | |||
| 252 | static int dh_init(DH *dh) | ||
| 253 | { | ||
| 254 | dh->flags |= DH_FLAG_CACHE_MONT_P; | ||
| 255 | return(1); | ||
| 256 | } | ||
| 257 | |||
| 258 | static int dh_finish(DH *dh) | ||
| 259 | { | ||
| 260 | if(dh->method_mont_p) | ||
| 261 | BN_MONT_CTX_free(dh->method_mont_p); | ||
| 262 | return(1); | ||
| 263 | } | ||
