diff options
Diffstat (limited to 'src/lib/libcrypto/dsa/dsa_sign.c')
| -rw-r--r-- | src/lib/libcrypto/dsa/dsa_sign.c | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/src/lib/libcrypto/dsa/dsa_sign.c b/src/lib/libcrypto/dsa/dsa_sign.c new file mode 100644 index 0000000000..6ca1c318f2 --- /dev/null +++ b/src/lib/libcrypto/dsa/dsa_sign.c | |||
| @@ -0,0 +1,215 @@ | |||
| 1 | /* crypto/dsa/dsa_sign.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 | /* Origional version from Steven Schoch <schoch@sheba.arc.nasa.gov> */ | ||
| 60 | |||
| 61 | #include <stdio.h> | ||
| 62 | #include "cryptlib.h" | ||
| 63 | #include "bn.h" | ||
| 64 | #include "dsa.h" | ||
| 65 | #include "rand.h" | ||
| 66 | #include "asn1.h" | ||
| 67 | |||
| 68 | /* data has already been hashed (probably with SHA or SHA-1). */ | ||
| 69 | /* DSAerr(DSA_F_DSA_SIGN,DSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE); */ | ||
| 70 | |||
| 71 | int DSA_sign(type,dgst,dlen,sig,siglen,dsa) | ||
| 72 | int type; | ||
| 73 | unsigned char *dgst; | ||
| 74 | int dlen; | ||
| 75 | unsigned char *sig; /* out */ | ||
| 76 | unsigned int *siglen; /* out */ | ||
| 77 | DSA *dsa; | ||
| 78 | { | ||
| 79 | BIGNUM *kinv=NULL,*r=NULL; | ||
| 80 | BIGNUM *m=NULL; | ||
| 81 | BIGNUM *xr=NULL,*s=NULL; | ||
| 82 | BN_CTX *ctx=NULL; | ||
| 83 | unsigned char *p; | ||
| 84 | int i,len=0,ret=0,reason=ERR_R_BN_LIB; | ||
| 85 | ASN1_INTEGER rbs,sbs; | ||
| 86 | MS_STATIC unsigned char rbuf[50]; /* assuming r is 20 bytes +extra */ | ||
| 87 | MS_STATIC unsigned char sbuf[50]; /* assuming s is 20 bytes +extra */ | ||
| 88 | |||
| 89 | i=BN_num_bytes(dsa->q); /* should be 20 */ | ||
| 90 | if ((dlen > i) || (dlen > 50)) | ||
| 91 | { | ||
| 92 | reason=DSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE; | ||
| 93 | goto err; | ||
| 94 | } | ||
| 95 | |||
| 96 | ctx=BN_CTX_new(); | ||
| 97 | if (ctx == NULL) goto err; | ||
| 98 | |||
| 99 | if ((dsa->kinv == NULL) || (dsa->r == NULL)) | ||
| 100 | { | ||
| 101 | if (!DSA_sign_setup(dsa,ctx,&kinv,&r)) goto err; | ||
| 102 | } | ||
| 103 | else | ||
| 104 | { | ||
| 105 | kinv=dsa->kinv; | ||
| 106 | dsa->kinv=NULL; | ||
| 107 | r=dsa->r; | ||
| 108 | dsa->r=NULL; | ||
| 109 | } | ||
| 110 | |||
| 111 | m=BN_new(); | ||
| 112 | xr=BN_new(); | ||
| 113 | s=BN_new(); | ||
| 114 | if (m == NULL || xr == NULL || s == NULL) goto err; | ||
| 115 | |||
| 116 | if (BN_bin2bn(dgst,dlen,m) == NULL) goto err; | ||
| 117 | |||
| 118 | /* Compute s = inv(k) (m + xr) mod q */ | ||
| 119 | if (!BN_mul(xr, dsa->priv_key, r)) goto err; /* s = xr */ | ||
| 120 | if (!BN_add(s, xr, m)) goto err; /* s = m + xr */ | ||
| 121 | if (!BN_mod_mul(s,s,kinv,dsa->q,ctx)) goto err; | ||
| 122 | |||
| 123 | /* | ||
| 124 | * Now create a ASN.1 sequence of the integers R and S. | ||
| 125 | */ | ||
| 126 | rbs.data=rbuf; | ||
| 127 | sbs.data=sbuf; | ||
| 128 | rbs.type = V_ASN1_INTEGER; | ||
| 129 | sbs.type = V_ASN1_INTEGER; | ||
| 130 | rbs.length=BN_bn2bin(r,rbs.data); | ||
| 131 | sbs.length=BN_bn2bin(s,sbs.data); | ||
| 132 | |||
| 133 | len =i2d_ASN1_INTEGER(&rbs,NULL); | ||
| 134 | len+=i2d_ASN1_INTEGER(&sbs,NULL); | ||
| 135 | |||
| 136 | p=sig; | ||
| 137 | ASN1_put_object(&p,1,len,V_ASN1_SEQUENCE,V_ASN1_UNIVERSAL); | ||
| 138 | i2d_ASN1_INTEGER(&rbs,&p); | ||
| 139 | i2d_ASN1_INTEGER(&sbs,&p); | ||
| 140 | *siglen=(p-sig); | ||
| 141 | ret=1; | ||
| 142 | err: | ||
| 143 | if (!ret) DSAerr(DSA_F_DSA_SIGN,reason); | ||
| 144 | |||
| 145 | #if 1 /* do the right thing :-) */ | ||
| 146 | if (kinv != NULL) BN_clear_free(kinv); | ||
| 147 | if (r != NULL) BN_clear_free(r); | ||
| 148 | #endif | ||
| 149 | if (ctx != NULL) BN_CTX_free(ctx); | ||
| 150 | if (m != NULL) BN_clear_free(m); | ||
| 151 | if (xr != NULL) BN_clear_free(xr); | ||
| 152 | if (s != NULL) BN_clear_free(s); | ||
| 153 | return(ret); | ||
| 154 | } | ||
| 155 | |||
| 156 | int DSA_sign_setup(dsa,ctx_in,kinvp,rp) | ||
| 157 | DSA *dsa; | ||
| 158 | BN_CTX *ctx_in; | ||
| 159 | BIGNUM **kinvp; | ||
| 160 | BIGNUM **rp; | ||
| 161 | { | ||
| 162 | BN_CTX *ctx; | ||
| 163 | BIGNUM *k=NULL,*kinv=NULL,*r=NULL; | ||
| 164 | int ret=0; | ||
| 165 | |||
| 166 | if (ctx_in == NULL) | ||
| 167 | { | ||
| 168 | if ((ctx=BN_CTX_new()) == NULL) goto err; | ||
| 169 | } | ||
| 170 | else | ||
| 171 | ctx=ctx_in; | ||
| 172 | |||
| 173 | r=BN_new(); | ||
| 174 | k=BN_new(); | ||
| 175 | if ((r == NULL) || (k == NULL)) | ||
| 176 | goto err; | ||
| 177 | kinv=NULL; | ||
| 178 | |||
| 179 | if (r == NULL) goto err; | ||
| 180 | |||
| 181 | /* Get random k */ | ||
| 182 | for (;;) | ||
| 183 | { | ||
| 184 | if (!BN_rand(k, BN_num_bits(dsa->q), 1, 0)) goto err; | ||
| 185 | if (BN_cmp(k,dsa->q) >= 0) | ||
| 186 | BN_sub(k,k,dsa->q); | ||
| 187 | if (!BN_is_zero(k)) break; | ||
| 188 | } | ||
| 189 | |||
| 190 | /* Compute r = (g^k mod p) mod q */ | ||
| 191 | if (!BN_mod_exp(r,dsa->g,k,dsa->p,ctx)) goto err; | ||
| 192 | if (!BN_mod(r,r,dsa->q,ctx)) goto err; | ||
| 193 | |||
| 194 | /* Compute part of 's = inv(k) (m + xr) mod q' */ | ||
| 195 | if ((kinv=BN_mod_inverse(k,dsa->q,ctx)) == NULL) goto err; | ||
| 196 | |||
| 197 | if (*kinvp != NULL) BN_clear_free(*kinvp); | ||
| 198 | *kinvp=kinv; | ||
| 199 | kinv=NULL; | ||
| 200 | if (*rp != NULL) BN_clear_free(*rp); | ||
| 201 | *rp=r; | ||
| 202 | ret=1; | ||
| 203 | err: | ||
| 204 | if (!ret) | ||
| 205 | { | ||
| 206 | DSAerr(DSA_F_DSA_SIGN_SETUP,ERR_R_BN_LIB); | ||
| 207 | if (kinv != NULL) BN_clear_free(kinv); | ||
| 208 | if (r != NULL) BN_clear_free(r); | ||
| 209 | } | ||
| 210 | if (ctx_in == NULL) BN_CTX_free(ctx); | ||
| 211 | if (k != NULL) BN_clear_free(k); | ||
| 212 | if (kinv != NULL) BN_clear_free(kinv); | ||
| 213 | return(ret); | ||
| 214 | } | ||
| 215 | |||
