crypto/dsa/dsa_pmeth.c

   1 /*
   2  * Copyright 2006-2016 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the OpenSSL license (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include <stdio.h>
  11 #include "internal/cryptlib.h"
  12 #include <openssl/asn1t.h>
  13 #include <openssl/x509.h>
  14 #include <openssl/evp.h>
  15 #include <openssl/bn.h>
  16 #include "internal/evp_int.h"
  17 #include "dsa_locl.h"
  18
  19 /* DSA pkey context structure */
  20
  21 typedef struct {
  22     /* Parameter gen parameters */
  23     int nbits;                  /* size of p in bits (default: 1024) */
  24     int qbits;                  /* size of q in bits (default: 160) */
  25     const EVP_MD *pmd;          /* MD for parameter generation */
  26     /* Keygen callback info */
  27     int gentmp[2];
  28     /* message digest */
  29     const EVP_MD *md;           /* MD for the signature */
  30 } DSA_PKEY_CTX;
  31
  32 static int pkey_dsa_init(EVP_PKEY_CTX *ctx)
  33 {
  34     DSA_PKEY_CTX *dctx = OPENSSL_malloc(sizeof(*dctx));
  35
  36     if (dctx == NULL)
  37         return 0;
  38     dctx->nbits = 1024;
  39     dctx->qbits = 160;
  40     dctx->pmd = NULL;
  41     dctx->md = NULL;
  42
  43     ctx->data = dctx;
  44     ctx->keygen_info = dctx->gentmp;
  45     ctx->keygen_info_count = 2;
  46
  47     return 1;
  48 }
  49
  50 static int pkey_dsa_copy(EVP_PKEY_CTX *dst, EVP_PKEY_CTX *src)
  51 {
  52     DSA_PKEY_CTX *dctx, *sctx;
  53
  54     if (!pkey_dsa_init(dst))
  55         return 0;
  56     sctx = src->data;
  57     dctx = dst->data;
  58     dctx->nbits = sctx->nbits;
  59     dctx->qbits = sctx->qbits;
  60     dctx->pmd = sctx->pmd;
  61     dctx->md = sctx->md;
  62     return 1;
  63 }
  64
  65 static void pkey_dsa_cleanup(EVP_PKEY_CTX *ctx)
  66 {
  67     DSA_PKEY_CTX *dctx = ctx->data;
  68     OPENSSL_free(dctx);
  69 }
  70
  71 static int pkey_dsa_sign(EVP_PKEY_CTX *ctx, unsigned char *sig,
  72                          size_t *siglen, const unsigned char *tbs,
  73                          size_t tbslen)
  74 {
  75     int ret;
  76     unsigned int sltmp;
  77     DSA_PKEY_CTX *dctx = ctx->data;
  78     DSA *dsa = ctx->pkey->pkey.dsa;
  79
  80     if (dctx->md) {
  81         if (tbslen != (size_t)EVP_MD_size(dctx->md))
  82             return 0;
  83     } else {
  84         if (tbslen != SHA_DIGEST_LENGTH)
  85             return 0;
  86     }
  87
  88     ret = DSA_sign(0, tbs, tbslen, sig, &sltmp, dsa);
  89
  90     if (ret <= 0)
  91         return ret;
  92     *siglen = sltmp;
  93     return 1;
  94 }
  95
  96 static int pkey_dsa_verify(EVP_PKEY_CTX *ctx,
  97                            const unsigned char *sig, size_t siglen,
  98                            const unsigned char *tbs, size_t tbslen)
  99 {
 100     int ret;
 101     DSA_PKEY_CTX *dctx = ctx->data;
 102     DSA *dsa = ctx->pkey->pkey.dsa;
 103
 104     if (dctx->md) {
 105         if (tbslen != (size_t)EVP_MD_size(dctx->md))
 106             return 0;
 107     } else {
 108         if (tbslen != SHA_DIGEST_LENGTH)
 109             return 0;
 110     }
 111
 112     ret = DSA_verify(0, tbs, tbslen, sig, siglen, dsa);
 113
 114     return ret;
 115 }
 116
 117 static int pkey_dsa_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
 118 {
 119     DSA_PKEY_CTX *dctx = ctx->data;
 120
 121     switch (type) {
 122     case EVP_PKEY_CTRL_DSA_PARAMGEN_BITS:
 123         if (p1 < 256)
 124             return -2;
 125         dctx->nbits = p1;
 126         return 1;
 127
 128     case EVP_PKEY_CTRL_DSA_PARAMGEN_Q_BITS:
 129         if (p1 != 160 && p1 != 224 && p1 && p1 != 256)
 130             return -2;
 131         dctx->qbits = p1;
 132         return 1;
 133
 134     case EVP_PKEY_CTRL_DSA_PARAMGEN_MD:
 135         if (EVP_MD_type((const EVP_MD *)p2) != NID_sha1 &&
 136             EVP_MD_type((const EVP_MD *)p2) != NID_sha224 &&
 137             EVP_MD_type((const EVP_MD *)p2) != NID_sha256) {
 138             DSAerr(DSA_F_PKEY_DSA_CTRL, DSA_R_INVALID_DIGEST_TYPE);
 139             return 0;
 140         }
 141         dctx->pmd = p2;
 142         return 1;
 143
 144     case EVP_PKEY_CTRL_MD:
 145         if (EVP_MD_type((const EVP_MD *)p2) != NID_sha1 &&
 146             EVP_MD_type((const EVP_MD *)p2) != NID_dsa &&
 147             EVP_MD_type((const EVP_MD *)p2) != NID_dsaWithSHA &&
 148             EVP_MD_type((const EVP_MD *)p2) != NID_sha224 &&
 149             EVP_MD_type((const EVP_MD *)p2) != NID_sha256 &&
 150             EVP_MD_type((const EVP_MD *)p2) != NID_sha384 &&
 151             EVP_MD_type((const EVP_MD *)p2) != NID_sha512) {
 152             DSAerr(DSA_F_PKEY_DSA_CTRL, DSA_R_INVALID_DIGEST_TYPE);
 153             return 0;
 154         }
 155         dctx->md = p2;
 156         return 1;
 157
 158     case EVP_PKEY_CTRL_GET_MD:
 159         *(const EVP_MD **)p2 = dctx->md;
 160         return 1;
 161
 162     case EVP_PKEY_CTRL_DIGESTINIT:
 163     case EVP_PKEY_CTRL_PKCS7_SIGN:
 164     case EVP_PKEY_CTRL_CMS_SIGN:
 165         return 1;
 166
 167     case EVP_PKEY_CTRL_PEER_KEY:
 168         DSAerr(DSA_F_PKEY_DSA_CTRL,
 169                EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
 170         return -2;
 171     default:
 172         return -2;
 173
 174     }
 175 }
 176
 177 static int pkey_dsa_ctrl_str(EVP_PKEY_CTX *ctx,
 178                              const char *type, const char *value)
 179 {
 180     if (strcmp(type, "dsa_paramgen_bits") == 0) {
 181         int nbits;
 182         nbits = atoi(value);
 183         return EVP_PKEY_CTX_set_dsa_paramgen_bits(ctx, nbits);
 184     }
 185     if (strcmp(type, "dsa_paramgen_q_bits") == 0) {
 186         int qbits = atoi(value);
 187         return EVP_PKEY_CTX_ctrl(ctx, EVP_PKEY_DSA, EVP_PKEY_OP_PARAMGEN,
 188                                  EVP_PKEY_CTRL_DSA_PARAMGEN_Q_BITS, qbits,
 189                                  NULL);
 190     }
 191     if (strcmp(type, "dsa_paramgen_md") == 0) {
 192         return EVP_PKEY_CTX_ctrl(ctx, EVP_PKEY_DSA, EVP_PKEY_OP_PARAMGEN,
 193                                  EVP_PKEY_CTRL_DSA_PARAMGEN_MD, 0,
 194                                  (void *)EVP_get_digestbyname(value));
 195     }
 196     return -2;
 197 }
 198
 199 static int pkey_dsa_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
 200 {
 201     DSA *dsa = NULL;
 202     DSA_PKEY_CTX *dctx = ctx->data;
 203     BN_GENCB *pcb;
 204     int ret;
 205
 206     if (ctx->pkey_gencb) {
 207         pcb = BN_GENCB_new();
 208         if (pcb == NULL)
 209             return 0;
 210         evp_pkey_set_cb_translate(pcb, ctx);
 211     } else
 212         pcb = NULL;
 213     dsa = DSA_new();
 214     if (dsa == NULL) {
 215         BN_GENCB_free(pcb);
 216         return 0;
 217     }
 218     ret = dsa_builtin_paramgen(dsa, dctx->nbits, dctx->qbits, dctx->pmd,
 219                                NULL, 0, NULL, NULL, NULL, pcb);
 220     BN_GENCB_free(pcb);
 221     if (ret)
 222         EVP_PKEY_assign_DSA(pkey, dsa);
 223     else
 224         DSA_free(dsa);
 225     return ret;
 226 }
 227
 228 static int pkey_dsa_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
 229 {
 230     DSA *dsa = NULL;
 231
 232     if (ctx->pkey == NULL) {
 233         DSAerr(DSA_F_PKEY_DSA_KEYGEN, DSA_R_NO_PARAMETERS_SET);
 234         return 0;
 235     }
 236     dsa = DSA_new();
 237     if (dsa == NULL)
 238         return 0;
 239     EVP_PKEY_assign_DSA(pkey, dsa);
 240     /* Note: if error return, pkey is freed by parent routine */
 241     if (!EVP_PKEY_copy_parameters(pkey, ctx->pkey))
 242         return 0;
 243     return DSA_generate_key(pkey->pkey.dsa);
 244 }
 245
 246 const EVP_PKEY_METHOD dsa_pkey_meth = {
 247     EVP_PKEY_DSA,
 248     EVP_PKEY_FLAG_AUTOARGLEN,
 249     pkey_dsa_init,
 250     pkey_dsa_copy,
 251     pkey_dsa_cleanup,
 252
 253     0,
 254     pkey_dsa_paramgen,
 255
 256     0,
 257     pkey_dsa_keygen,
 258
 259     0,
 260     pkey_dsa_sign,
 261
 262     0,
 263     pkey_dsa_verify,
 264
 265     0, 0,
 266
 267     0, 0, 0, 0,
 268
 269     0, 0,
 270
 271     0, 0,
 272
 273     0, 0,
 274
 275     pkey_dsa_ctrl,
 276     pkey_dsa_ctrl_str
 277 };