crypto/rsa/rsa_ameth.c

   1 /* crypto/rsa/rsa_ameth.c */
   2 /*
   3  * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
   4  * 2006.
   5  */
   6 /* ====================================================================
   7  * Copyright (c) 2006 The OpenSSL Project.  All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  *
  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
  19  *    distribution.
  20  *
  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/)"
  25  *
  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.
  30  *
  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.
  34  *
  35  * 6. Redistributions of any form whatsoever must retain the following
  36  *    acknowledgment:
  37  *    "This product includes software developed by the OpenSSL Project
  38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  39  *
  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  * ====================================================================
  53  *
  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).
  57  *
  58  */
  59
  60 #include <stdio.h>
  61 #include "cryptlib.h"
  62 #include <openssl/asn1t.h>
  63 #include <openssl/x509.h>
  64 #include <openssl/rsa.h>
  65 #include <openssl/bn.h>
  66 #ifndef OPENSSL_NO_CMS
  67 # include <openssl/cms.h>
  68 #endif
  69 #include "asn1_locl.h"
  70
  71 static int rsa_cms_sign(CMS_SignerInfo *si);
  72 static int rsa_cms_verify(CMS_SignerInfo *si);
  73 static int rsa_cms_decrypt(CMS_RecipientInfo *ri);
  74 static int rsa_cms_encrypt(CMS_RecipientInfo *ri);
  75
  76 static int rsa_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
  77 {
  78     unsigned char *penc = NULL;
  79     int penclen;
  80     penclen = i2d_RSAPublicKey(pkey->pkey.rsa, &penc);
  81     if (penclen <= 0)
  82         return 0;
  83     if (X509_PUBKEY_set0_param(pk, OBJ_nid2obj(EVP_PKEY_RSA),
  84                                V_ASN1_NULL, NULL, penc, penclen))
  85         return 1;
  86
  87     OPENSSL_free(penc);
  88     return 0;
  89 }
  90
  91 static int rsa_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey)
  92 {
  93     const unsigned char *p;
  94     int pklen;
  95     RSA *rsa = NULL;
  96     if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, NULL, pubkey))
  97         return 0;
  98     if (!(rsa = d2i_RSAPublicKey(NULL, &p, pklen))) {
  99         RSAerr(RSA_F_RSA_PUB_DECODE, ERR_R_RSA_LIB);
 100         return 0;
 101     }
 102     EVP_PKEY_assign_RSA(pkey, rsa);
 103     return 1;
 104 }
 105
 106 static int rsa_pub_cmp(const EVP_PKEY *a, const EVP_PKEY *b)
 107 {
 108     if (BN_cmp(b->pkey.rsa->n, a->pkey.rsa->n) != 0
 109         || BN_cmp(b->pkey.rsa->e, a->pkey.rsa->e) != 0)
 110         return 0;
 111     return 1;
 112 }
 113
 114 static int old_rsa_priv_decode(EVP_PKEY *pkey,
 115                                const unsigned char **pder, int derlen)
 116 {
 117     RSA *rsa;
 118     if (!(rsa = d2i_RSAPrivateKey(NULL, pder, derlen))) {
 119         RSAerr(RSA_F_OLD_RSA_PRIV_DECODE, ERR_R_RSA_LIB);
 120         return 0;
 121     }
 122     EVP_PKEY_assign_RSA(pkey, rsa);
 123     return 1;
 124 }
 125
 126 static int old_rsa_priv_encode(const EVP_PKEY *pkey, unsigned char **pder)
 127 {
 128     return i2d_RSAPrivateKey(pkey->pkey.rsa, pder);
 129 }
 130
 131 static int rsa_priv_encode(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pkey)
 132 {
 133     unsigned char *rk = NULL;
 134     int rklen;
 135     rklen = i2d_RSAPrivateKey(pkey->pkey.rsa, &rk);
 136
 137     if (rklen <= 0) {
 138         RSAerr(RSA_F_RSA_PRIV_ENCODE, ERR_R_MALLOC_FAILURE);
 139         return 0;
 140     }
 141
 142     if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(NID_rsaEncryption), 0,
 143                          V_ASN1_NULL, NULL, rk, rklen)) {
 144         RSAerr(RSA_F_RSA_PRIV_ENCODE, ERR_R_MALLOC_FAILURE);
 145         return 0;
 146     }
 147
 148     return 1;
 149 }
 150
 151 static int rsa_priv_decode(EVP_PKEY *pkey, PKCS8_PRIV_KEY_INFO *p8)
 152 {
 153     const unsigned char *p;
 154     int pklen;
 155     if (!PKCS8_pkey_get0(NULL, &p, &pklen, NULL, p8))
 156         return 0;
 157     return old_rsa_priv_decode(pkey, &p, pklen);
 158 }
 159
 160 static int int_rsa_size(const EVP_PKEY *pkey)
 161 {
 162     return RSA_size(pkey->pkey.rsa);
 163 }
 164
 165 static int rsa_bits(const EVP_PKEY *pkey)
 166 {
 167     return BN_num_bits(pkey->pkey.rsa->n);
 168 }
 169
 170 static int rsa_security_bits(const EVP_PKEY *pkey)
 171 {
 172     return RSA_security_bits(pkey->pkey.rsa);
 173 }
 174
 175 static void int_rsa_free(EVP_PKEY *pkey)
 176 {
 177     RSA_free(pkey->pkey.rsa);
 178 }
 179
 180 static void update_buflen(const BIGNUM *b, size_t *pbuflen)
 181 {
 182     size_t i;
 183     if (!b)
 184         return;
 185     if (*pbuflen < (i = (size_t)BN_num_bytes(b)))
 186         *pbuflen = i;
 187 }
 188
 189 static int do_rsa_print(BIO *bp, const RSA *x, int off, int priv)
 190 {
 191     char *str;
 192     const char *s;
 193     unsigned char *m = NULL;
 194     int ret = 0, mod_len = 0;
 195     size_t buf_len = 0;
 196
 197     update_buflen(x->n, &buf_len);
 198     update_buflen(x->e, &buf_len);
 199
 200     if (priv) {
 201         update_buflen(x->d, &buf_len);
 202         update_buflen(x->p, &buf_len);
 203         update_buflen(x->q, &buf_len);
 204         update_buflen(x->dmp1, &buf_len);
 205         update_buflen(x->dmq1, &buf_len);
 206         update_buflen(x->iqmp, &buf_len);
 207     }
 208
 209     m = (unsigned char *)OPENSSL_malloc(buf_len + 10);
 210     if (m == NULL) {
 211         RSAerr(RSA_F_DO_RSA_PRINT, ERR_R_MALLOC_FAILURE);
 212         goto err;
 213     }
 214
 215     if (x->n != NULL)
 216         mod_len = BN_num_bits(x->n);
 217
 218     if (!BIO_indent(bp, off, 128))
 219         goto err;
 220
 221     if (priv && x->d) {
 222         if (BIO_printf(bp, "Private-Key: (%d bit)\n", mod_len)
 223             <= 0)
 224             goto err;
 225         str = "modulus:";
 226         s = "publicExponent:";
 227     } else {
 228         if (BIO_printf(bp, "Public-Key: (%d bit)\n", mod_len)
 229             <= 0)
 230             goto err;
 231         str = "Modulus:";
 232         s = "Exponent:";
 233     }
 234     if (!ASN1_bn_print(bp, str, x->n, m, off))
 235         goto err;
 236     if (!ASN1_bn_print(bp, s, x->e, m, off))
 237         goto err;
 238     if (priv) {
 239         if (!ASN1_bn_print(bp, "privateExponent:", x->d, m, off))
 240             goto err;
 241         if (!ASN1_bn_print(bp, "prime1:", x->p, m, off))
 242             goto err;
 243         if (!ASN1_bn_print(bp, "prime2:", x->q, m, off))
 244             goto err;
 245         if (!ASN1_bn_print(bp, "exponent1:", x->dmp1, m, off))
 246             goto err;
 247         if (!ASN1_bn_print(bp, "exponent2:", x->dmq1, m, off))
 248             goto err;
 249         if (!ASN1_bn_print(bp, "coefficient:", x->iqmp, m, off))
 250             goto err;
 251     }
 252     ret = 1;
 253  err:
 254     if (m != NULL)
 255         OPENSSL_free(m);
 256     return (ret);
 257 }
 258
 259 static int rsa_pub_print(BIO *bp, const EVP_PKEY *pkey, int indent,
 260                          ASN1_PCTX *ctx)
 261 {
 262     return do_rsa_print(bp, pkey->pkey.rsa, indent, 0);
 263 }
 264
 265 static int rsa_priv_print(BIO *bp, const EVP_PKEY *pkey, int indent,
 266                           ASN1_PCTX *ctx)
 267 {
 268     return do_rsa_print(bp, pkey->pkey.rsa, indent, 1);
 269 }
 270
 271 /* Given an MGF1 Algorithm ID decode to an Algorithm Identifier */
 272 static X509_ALGOR *rsa_mgf1_decode(X509_ALGOR *alg)
 273 {
 274     const unsigned char *p;
 275     int plen;
 276     if (alg == NULL)
 277         return NULL;
 278     if (OBJ_obj2nid(alg->algorithm) != NID_mgf1)
 279         return NULL;
 280     if (alg->parameter->type != V_ASN1_SEQUENCE)
 281         return NULL;
 282
 283     p = alg->parameter->value.sequence->data;
 284     plen = alg->parameter->value.sequence->length;
 285     return d2i_X509_ALGOR(NULL, &p, plen);
 286 }
 287
 288 static RSA_PSS_PARAMS *rsa_pss_decode(const X509_ALGOR *alg,
 289                                       X509_ALGOR **pmaskHash)
 290 {
 291     const unsigned char *p;
 292     int plen;
 293     RSA_PSS_PARAMS *pss;
 294
 295     *pmaskHash = NULL;
 296
 297     if (!alg->parameter || alg->parameter->type != V_ASN1_SEQUENCE)
 298         return NULL;
 299     p = alg->parameter->value.sequence->data;
 300     plen = alg->parameter->value.sequence->length;
 301     pss = d2i_RSA_PSS_PARAMS(NULL, &p, plen);
 302
 303     if (!pss)
 304         return NULL;
 305
 306     *pmaskHash = rsa_mgf1_decode(pss->maskGenAlgorithm);
 307
 308     return pss;
 309 }
 310
 311 static int rsa_pss_param_print(BIO *bp, RSA_PSS_PARAMS *pss,
 312                                X509_ALGOR *maskHash, int indent)
 313 {
 314     int rv = 0;
 315     if (!pss) {
 316         if (BIO_puts(bp, " (INVALID PSS PARAMETERS)\n") <= 0)
 317             return 0;
 318         return 1;
 319     }
 320     if (BIO_puts(bp, "\n") <= 0)
 321         goto err;
 322     if (!BIO_indent(bp, indent, 128))
 323         goto err;
 324     if (BIO_puts(bp, "Hash Algorithm: ") <= 0)
 325         goto err;
 326
 327     if (pss->hashAlgorithm) {
 328         if (i2a_ASN1_OBJECT(bp, pss->hashAlgorithm->algorithm) <= 0)
 329             goto err;
 330     } else if (BIO_puts(bp, "sha1 (default)") <= 0)
 331         goto err;
 332
 333     if (BIO_puts(bp, "\n") <= 0)
 334         goto err;
 335
 336     if (!BIO_indent(bp, indent, 128))
 337         goto err;
 338
 339     if (BIO_puts(bp, "Mask Algorithm: ") <= 0)
 340         goto err;
 341     if (pss->maskGenAlgorithm) {
 342         if (i2a_ASN1_OBJECT(bp, pss->maskGenAlgorithm->algorithm) <= 0)
 343             goto err;
 344         if (BIO_puts(bp, " with ") <= 0)
 345             goto err;
 346         if (maskHash) {
 347             if (i2a_ASN1_OBJECT(bp, maskHash->algorithm) <= 0)
 348                 goto err;
 349         } else if (BIO_puts(bp, "INVALID") <= 0)
 350             goto err;
 351     } else if (BIO_puts(bp, "mgf1 with sha1 (default)") <= 0)
 352         goto err;
 353     BIO_puts(bp, "\n");
 354
 355     if (!BIO_indent(bp, indent, 128))
 356         goto err;
 357     if (BIO_puts(bp, "Salt Length: 0x") <= 0)
 358         goto err;
 359     if (pss->saltLength) {
 360         if (i2a_ASN1_INTEGER(bp, pss->saltLength) <= 0)
 361             goto err;
 362     } else if (BIO_puts(bp, "14 (default)") <= 0)
 363         goto err;
 364     BIO_puts(bp, "\n");
 365
 366     if (!BIO_indent(bp, indent, 128))
 367         goto err;
 368     if (BIO_puts(bp, "Trailer Field: 0x") <= 0)
 369         goto err;
 370     if (pss->trailerField) {
 371         if (i2a_ASN1_INTEGER(bp, pss->trailerField) <= 0)
 372             goto err;
 373     } else if (BIO_puts(bp, "BC (default)") <= 0)
 374         goto err;
 375     BIO_puts(bp, "\n");
 376
 377     rv = 1;
 378
 379  err:
 380     return rv;
 381
 382 }
 383
 384 static int rsa_sig_print(BIO *bp, const X509_ALGOR *sigalg,
 385                          const ASN1_STRING *sig, int indent, ASN1_PCTX *pctx)
 386 {
 387     if (OBJ_obj2nid(sigalg->algorithm) == NID_rsassaPss) {
 388         int rv;
 389         RSA_PSS_PARAMS *pss;
 390         X509_ALGOR *maskHash;
 391         pss = rsa_pss_decode(sigalg, &maskHash);
 392         rv = rsa_pss_param_print(bp, pss, maskHash, indent);
 393         if (pss)
 394             RSA_PSS_PARAMS_free(pss);
 395         if (maskHash)
 396             X509_ALGOR_free(maskHash);
 397         if (!rv)
 398             return 0;
 399     } else if (!sig && BIO_puts(bp, "\n") <= 0)
 400         return 0;
 401     if (sig)
 402         return X509_signature_dump(bp, sig, indent);
 403     return 1;
 404 }
 405
 406 static int rsa_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2)
 407 {
 408     X509_ALGOR *alg = NULL;
 409     switch (op) {
 410
 411     case ASN1_PKEY_CTRL_PKCS7_SIGN:
 412         if (arg1 == 0)
 413             PKCS7_SIGNER_INFO_get0_algs(arg2, NULL, NULL, &alg);
 414         break;
 415
 416     case ASN1_PKEY_CTRL_PKCS7_ENCRYPT:
 417         if (arg1 == 0)
 418             PKCS7_RECIP_INFO_get0_alg(arg2, &alg);
 419         break;
 420 #ifndef OPENSSL_NO_CMS
 421     case ASN1_PKEY_CTRL_CMS_SIGN:
 422         if (arg1 == 0)
 423             return rsa_cms_sign(arg2);
 424         else if (arg1 == 1)
 425             return rsa_cms_verify(arg2);
 426         break;
 427
 428     case ASN1_PKEY_CTRL_CMS_ENVELOPE:
 429         if (arg1 == 0)
 430             return rsa_cms_encrypt(arg2);
 431         else if (arg1 == 1)
 432             return rsa_cms_decrypt(arg2);
 433         break;
 434
 435     case ASN1_PKEY_CTRL_CMS_RI_TYPE:
 436         *(int *)arg2 = CMS_RECIPINFO_TRANS;
 437         return 1;
 438 #endif
 439
 440     case ASN1_PKEY_CTRL_DEFAULT_MD_NID:
 441         *(int *)arg2 = NID_sha256;
 442         return 1;
 443
 444     default:
 445         return -2;
 446
 447     }
 448
 449     if (alg)
 450         X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsaEncryption), V_ASN1_NULL, 0);
 451
 452     return 1;
 453
 454 }
 455
 456 /* allocate and set algorithm ID from EVP_MD, default SHA1 */
 457 static int rsa_md_to_algor(X509_ALGOR **palg, const EVP_MD *md)
 458 {
 459     if (EVP_MD_type(md) == NID_sha1)
 460         return 1;
 461     *palg = X509_ALGOR_new();
 462     if (!*palg)
 463         return 0;
 464     X509_ALGOR_set_md(*palg, md);
 465     return 1;
 466 }
 467
 468 /* Allocate and set MGF1 algorithm ID from EVP_MD */
 469 static int rsa_md_to_mgf1(X509_ALGOR **palg, const EVP_MD *mgf1md)
 470 {
 471     X509_ALGOR *algtmp = NULL;
 472     ASN1_STRING *stmp = NULL;
 473     *palg = NULL;
 474     if (EVP_MD_type(mgf1md) == NID_sha1)
 475         return 1;
 476     /* need to embed algorithm ID inside another */
 477     if (!rsa_md_to_algor(&algtmp, mgf1md))
 478         goto err;
 479     if (!ASN1_item_pack(algtmp, ASN1_ITEM_rptr(X509_ALGOR), &stmp))
 480          goto err;
 481     *palg = X509_ALGOR_new();
 482     if (!*palg)
 483         goto err;
 484     X509_ALGOR_set0(*palg, OBJ_nid2obj(NID_mgf1), V_ASN1_SEQUENCE, stmp);
 485     stmp = NULL;
 486  err:
 487     if (stmp)
 488         ASN1_STRING_free(stmp);
 489     if (algtmp)
 490         X509_ALGOR_free(algtmp);
 491     if (*palg)
 492         return 1;
 493     return 0;
 494 }
 495
 496 /* convert algorithm ID to EVP_MD, default SHA1 */
 497 static const EVP_MD *rsa_algor_to_md(X509_ALGOR *alg)
 498 {
 499     const EVP_MD *md;
 500     if (!alg)
 501         return EVP_sha1();
 502     md = EVP_get_digestbyobj(alg->algorithm);
 503     if (md == NULL)
 504         RSAerr(RSA_F_RSA_ALGOR_TO_MD, RSA_R_UNKNOWN_DIGEST);
 505     return md;
 506 }
 507
 508 /* convert MGF1 algorithm ID to EVP_MD, default SHA1 */
 509 static const EVP_MD *rsa_mgf1_to_md(X509_ALGOR *alg, X509_ALGOR *maskHash)
 510 {
 511     const EVP_MD *md;
 512     if (!alg)
 513         return EVP_sha1();
 514     /* Check mask and lookup mask hash algorithm */
 515     if (OBJ_obj2nid(alg->algorithm) != NID_mgf1) {
 516         RSAerr(RSA_F_RSA_MGF1_TO_MD, RSA_R_UNSUPPORTED_MASK_ALGORITHM);
 517         return NULL;
 518     }
 519     if (!maskHash) {
 520         RSAerr(RSA_F_RSA_MGF1_TO_MD, RSA_R_UNSUPPORTED_MASK_PARAMETER);
 521         return NULL;
 522     }
 523     md = EVP_get_digestbyobj(maskHash->algorithm);
 524     if (md == NULL) {
 525         RSAerr(RSA_F_RSA_MGF1_TO_MD, RSA_R_UNKNOWN_MASK_DIGEST);
 526         return NULL;
 527     }
 528     return md;
 529 }
 530
 531 /*
 532  * Convert EVP_PKEY_CTX is PSS mode into corresponding algorithm parameter,
 533  * suitable for setting an AlgorithmIdentifier.
 534  */
 535
 536 static ASN1_STRING *rsa_ctx_to_pss(EVP_PKEY_CTX *pkctx)
 537 {
 538     const EVP_MD *sigmd, *mgf1md;
 539     RSA_PSS_PARAMS *pss = NULL;
 540     ASN1_STRING *os = NULL;
 541     EVP_PKEY *pk = EVP_PKEY_CTX_get0_pkey(pkctx);
 542     int saltlen, rv = 0;
 543     if (EVP_PKEY_CTX_get_signature_md(pkctx, &sigmd) <= 0)
 544         goto err;
 545     if (EVP_PKEY_CTX_get_rsa_mgf1_md(pkctx, &mgf1md) <= 0)
 546         goto err;
 547     if (!EVP_PKEY_CTX_get_rsa_pss_saltlen(pkctx, &saltlen))
 548         goto err;
 549     if (saltlen == -1)
 550         saltlen = EVP_MD_size(sigmd);
 551     else if (saltlen == -2) {
 552         saltlen = EVP_PKEY_size(pk) - EVP_MD_size(sigmd) - 2;
 553         if (((EVP_PKEY_bits(pk) - 1) & 0x7) == 0)
 554             saltlen--;
 555     }
 556     pss = RSA_PSS_PARAMS_new();
 557     if (!pss)
 558         goto err;
 559     if (saltlen != 20) {
 560         pss->saltLength = ASN1_INTEGER_new();
 561         if (!pss->saltLength)
 562             goto err;
 563         if (!ASN1_INTEGER_set(pss->saltLength, saltlen))
 564             goto err;
 565     }
 566     if (!rsa_md_to_algor(&pss->hashAlgorithm, sigmd))
 567         goto err;
 568     if (!rsa_md_to_mgf1(&pss->maskGenAlgorithm, mgf1md))
 569         goto err;
 570     /* Finally create string with pss parameter encoding. */
 571     if (!ASN1_item_pack(pss, ASN1_ITEM_rptr(RSA_PSS_PARAMS), &os))
 572          goto err;
 573     rv = 1;
 574  err:
 575     if (pss)
 576         RSA_PSS_PARAMS_free(pss);
 577     if (rv)
 578         return os;
 579     if (os)
 580         ASN1_STRING_free(os);
 581     return NULL;
 582 }
 583
 584 /*
 585  * From PSS AlgorithmIdentifier set public key parameters. If pkey isn't NULL
 586  * then the EVP_MD_CTX is setup and initalised. If it is NULL parameters are
 587  * passed to pkctx instead.
 588  */
 589
 590 static int rsa_pss_to_ctx(EVP_MD_CTX *ctx, EVP_PKEY_CTX *pkctx,
 591                           X509_ALGOR *sigalg, EVP_PKEY *pkey)
 592 {
 593     int rv = -1;
 594     int saltlen;
 595     const EVP_MD *mgf1md = NULL, *md = NULL;
 596     RSA_PSS_PARAMS *pss;
 597     X509_ALGOR *maskHash;
 598     /* Sanity check: make sure it is PSS */
 599     if (OBJ_obj2nid(sigalg->algorithm) != NID_rsassaPss) {
 600         RSAerr(RSA_F_RSA_PSS_TO_CTX, RSA_R_UNSUPPORTED_SIGNATURE_TYPE);
 601         return -1;
 602     }
 603     /* Decode PSS parameters */
 604     pss = rsa_pss_decode(sigalg, &maskHash);
 605
 606     if (pss == NULL) {
 607         RSAerr(RSA_F_RSA_PSS_TO_CTX, RSA_R_INVALID_PSS_PARAMETERS);
 608         goto err;
 609     }
 610     mgf1md = rsa_mgf1_to_md(pss->maskGenAlgorithm, maskHash);
 611     if (!mgf1md)
 612         goto err;
 613     md = rsa_algor_to_md(pss->hashAlgorithm);
 614     if (!md)
 615         goto err;
 616
 617     if (pss->saltLength) {
 618         saltlen = ASN1_INTEGER_get(pss->saltLength);
 619
 620         /*
 621          * Could perform more salt length sanity checks but the main RSA
 622          * routines will trap other invalid values anyway.
 623          */
 624         if (saltlen < 0) {
 625             RSAerr(RSA_F_RSA_PSS_TO_CTX, RSA_R_INVALID_SALT_LENGTH);
 626             goto err;
 627         }
 628     } else
 629         saltlen = 20;
 630
 631     /*
 632      * low-level routines support only trailer field 0xbc (value 1) and
 633      * PKCS#1 says we should reject any other value anyway.
 634      */
 635     if (pss->trailerField && ASN1_INTEGER_get(pss->trailerField) != 1) {
 636         RSAerr(RSA_F_RSA_PSS_TO_CTX, RSA_R_INVALID_TRAILER);
 637         goto err;
 638     }
 639
 640     /* We have all parameters now set up context */
 641
 642     if (pkey) {
 643         if (!EVP_DigestVerifyInit(ctx, &pkctx, md, NULL, pkey))
 644             goto err;
 645     } else {
 646         const EVP_MD *checkmd;
 647         if (EVP_PKEY_CTX_get_signature_md(pkctx, &checkmd) <= 0)
 648             goto err;
 649         if (EVP_MD_type(md) != EVP_MD_type(checkmd)) {
 650             RSAerr(RSA_F_RSA_PSS_TO_CTX, RSA_R_DIGEST_DOES_NOT_MATCH);
 651             goto err;
 652         }
 653     }
 654
 655     if (EVP_PKEY_CTX_set_rsa_padding(pkctx, RSA_PKCS1_PSS_PADDING) <= 0)
 656         goto err;
 657
 658     if (EVP_PKEY_CTX_set_rsa_pss_saltlen(pkctx, saltlen) <= 0)
 659         goto err;
 660
 661     if (EVP_PKEY_CTX_set_rsa_mgf1_md(pkctx, mgf1md) <= 0)
 662         goto err;
 663     /* Carry on */
 664     rv = 1;
 665
 666  err:
 667     RSA_PSS_PARAMS_free(pss);
 668     if (maskHash)
 669         X509_ALGOR_free(maskHash);
 670     return rv;
 671 }
 672
 673 static int rsa_cms_verify(CMS_SignerInfo *si)
 674 {
 675     int nid, nid2;
 676     X509_ALGOR *alg;
 677     EVP_PKEY_CTX *pkctx = CMS_SignerInfo_get0_pkey_ctx(si);
 678     CMS_SignerInfo_get0_algs(si, NULL, NULL, NULL, &alg);
 679     nid = OBJ_obj2nid(alg->algorithm);
 680     if (nid == NID_rsaEncryption)
 681         return 1;
 682     if (nid == NID_rsassaPss)
 683         return rsa_pss_to_ctx(NULL, pkctx, alg, NULL);
 684     /* Workaround for some implementation that use a signature OID */
 685     if (OBJ_find_sigid_algs(nid, NULL, &nid2)) {
 686         if (nid2 == NID_rsaEncryption)
 687             return 1;
 688     }
 689     return 0;
 690 }
 691
 692 /*
 693  * Customised RSA item verification routine. This is called when a signature
 694  * is encountered requiring special handling. We currently only handle PSS.
 695  */
 696
 697 static int rsa_item_verify(EVP_MD_CTX *ctx, const ASN1_ITEM *it, void *asn,
 698                            X509_ALGOR *sigalg, ASN1_BIT_STRING *sig,
 699                            EVP_PKEY *pkey)
 700 {
 701     /* Sanity check: make sure it is PSS */
 702     if (OBJ_obj2nid(sigalg->algorithm) != NID_rsassaPss) {
 703         RSAerr(RSA_F_RSA_ITEM_VERIFY, RSA_R_UNSUPPORTED_SIGNATURE_TYPE);
 704         return -1;
 705     }
 706     if (rsa_pss_to_ctx(ctx, NULL, sigalg, pkey))
 707         /* Carry on */
 708         return 2;
 709     return -1;
 710 }
 711
 712 static int rsa_cms_sign(CMS_SignerInfo *si)
 713 {
 714     int pad_mode = RSA_PKCS1_PADDING;
 715     X509_ALGOR *alg;
 716     EVP_PKEY_CTX *pkctx = CMS_SignerInfo_get0_pkey_ctx(si);
 717     ASN1_STRING *os = NULL;
 718     CMS_SignerInfo_get0_algs(si, NULL, NULL, NULL, &alg);
 719     if (pkctx) {
 720         if (EVP_PKEY_CTX_get_rsa_padding(pkctx, &pad_mode) <= 0)
 721             return 0;
 722     }
 723     if (pad_mode == RSA_PKCS1_PADDING) {
 724         X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsaEncryption), V_ASN1_NULL, 0);
 725         return 1;
 726     }
 727     /* We don't support it */
 728     if (pad_mode != RSA_PKCS1_PSS_PADDING)
 729         return 0;
 730     os = rsa_ctx_to_pss(pkctx);
 731     if (!os)
 732         return 0;
 733     X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsassaPss), V_ASN1_SEQUENCE, os);
 734     return 1;
 735 }
 736
 737 static int rsa_item_sign(EVP_MD_CTX *ctx, const ASN1_ITEM *it, void *asn,
 738                          X509_ALGOR *alg1, X509_ALGOR *alg2,
 739                          ASN1_BIT_STRING *sig)
 740 {
 741     int pad_mode;
 742     EVP_PKEY_CTX *pkctx = ctx->pctx;
 743     if (EVP_PKEY_CTX_get_rsa_padding(pkctx, &pad_mode) <= 0)
 744         return 0;
 745     if (pad_mode == RSA_PKCS1_PADDING)
 746         return 2;
 747     if (pad_mode == RSA_PKCS1_PSS_PADDING) {
 748         ASN1_STRING *os1 = NULL;
 749         os1 = rsa_ctx_to_pss(pkctx);
 750         if (!os1)
 751             return 0;
 752         /* Duplicate parameters if we have to */
 753         if (alg2) {
 754             ASN1_STRING *os2 = ASN1_STRING_dup(os1);
 755             if (!os2) {
 756                 ASN1_STRING_free(os1);
 757                 return 0;
 758             }
 759             X509_ALGOR_set0(alg2, OBJ_nid2obj(NID_rsassaPss),
 760                             V_ASN1_SEQUENCE, os2);
 761         }
 762         X509_ALGOR_set0(alg1, OBJ_nid2obj(NID_rsassaPss),
 763                         V_ASN1_SEQUENCE, os1);
 764         return 3;
 765     }
 766     return 2;
 767 }
 768
 769 static RSA_OAEP_PARAMS *rsa_oaep_decode(const X509_ALGOR *alg,
 770                                         X509_ALGOR **pmaskHash)
 771 {
 772     const unsigned char *p;
 773     int plen;
 774     RSA_OAEP_PARAMS *pss;
 775
 776     *pmaskHash = NULL;
 777
 778     if (!alg->parameter || alg->parameter->type != V_ASN1_SEQUENCE)
 779         return NULL;
 780     p = alg->parameter->value.sequence->data;
 781     plen = alg->parameter->value.sequence->length;
 782     pss = d2i_RSA_OAEP_PARAMS(NULL, &p, plen);
 783
 784     if (!pss)
 785         return NULL;
 786
 787     *pmaskHash = rsa_mgf1_decode(pss->maskGenFunc);
 788
 789     return pss;
 790 }
 791
 792 static int rsa_cms_decrypt(CMS_RecipientInfo *ri)
 793 {
 794     EVP_PKEY_CTX *pkctx;
 795     X509_ALGOR *cmsalg;
 796     int nid;
 797     int rv = -1;
 798     unsigned char *label = NULL;
 799     int labellen = 0;
 800     const EVP_MD *mgf1md = NULL, *md = NULL;
 801     RSA_OAEP_PARAMS *oaep;
 802     X509_ALGOR *maskHash;
 803     pkctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
 804     if (!pkctx)
 805         return 0;
 806     if (!CMS_RecipientInfo_ktri_get0_algs(ri, NULL, NULL, &cmsalg))
 807         return -1;
 808     nid = OBJ_obj2nid(cmsalg->algorithm);
 809     if (nid == NID_rsaEncryption)
 810         return 1;
 811     if (nid != NID_rsaesOaep) {
 812         RSAerr(RSA_F_RSA_CMS_DECRYPT, RSA_R_UNSUPPORTED_ENCRYPTION_TYPE);
 813         return -1;
 814     }
 815     /* Decode OAEP parameters */
 816     oaep = rsa_oaep_decode(cmsalg, &maskHash);
 817
 818     if (oaep == NULL) {
 819         RSAerr(RSA_F_RSA_CMS_DECRYPT, RSA_R_INVALID_OAEP_PARAMETERS);
 820         goto err;
 821     }
 822
 823     mgf1md = rsa_mgf1_to_md(oaep->maskGenFunc, maskHash);
 824     if (!mgf1md)
 825         goto err;
 826     md = rsa_algor_to_md(oaep->hashFunc);
 827     if (!md)
 828         goto err;
 829
 830     if (oaep->pSourceFunc) {
 831         X509_ALGOR *plab = oaep->pSourceFunc;
 832         if (OBJ_obj2nid(plab->algorithm) != NID_pSpecified) {
 833             RSAerr(RSA_F_RSA_CMS_DECRYPT, RSA_R_UNSUPPORTED_LABEL_SOURCE);
 834             goto err;
 835         }
 836         if (plab->parameter->type != V_ASN1_OCTET_STRING) {
 837             RSAerr(RSA_F_RSA_CMS_DECRYPT, RSA_R_INVALID_LABEL);
 838             goto err;
 839         }
 840
 841         label = plab->parameter->value.octet_string->data;
 842         /* Stop label being freed when OAEP parameters are freed */
 843         plab->parameter->value.octet_string->data = NULL;
 844         labellen = plab->parameter->value.octet_string->length;
 845     }
 846
 847     if (EVP_PKEY_CTX_set_rsa_padding(pkctx, RSA_PKCS1_OAEP_PADDING) <= 0)
 848         goto err;
 849     if (EVP_PKEY_CTX_set_rsa_oaep_md(pkctx, md) <= 0)
 850         goto err;
 851     if (EVP_PKEY_CTX_set_rsa_mgf1_md(pkctx, mgf1md) <= 0)
 852         goto err;
 853     if (EVP_PKEY_CTX_set0_rsa_oaep_label(pkctx, label, labellen) <= 0)
 854         goto err;
 855     /* Carry on */
 856     rv = 1;
 857
 858  err:
 859     RSA_OAEP_PARAMS_free(oaep);
 860     if (maskHash)
 861         X509_ALGOR_free(maskHash);
 862     return rv;
 863 }
 864
 865 static int rsa_cms_encrypt(CMS_RecipientInfo *ri)
 866 {
 867     const EVP_MD *md, *mgf1md;
 868     RSA_OAEP_PARAMS *oaep = NULL;
 869     ASN1_STRING *os = NULL;
 870     X509_ALGOR *alg;
 871     EVP_PKEY_CTX *pkctx = CMS_RecipientInfo_get0_pkey_ctx(ri);
 872     int pad_mode = RSA_PKCS1_PADDING, rv = 0, labellen;
 873     unsigned char *label;
 874     CMS_RecipientInfo_ktri_get0_algs(ri, NULL, NULL, &alg);
 875     if (pkctx) {
 876         if (EVP_PKEY_CTX_get_rsa_padding(pkctx, &pad_mode) <= 0)
 877             return 0;
 878     }
 879     if (pad_mode == RSA_PKCS1_PADDING) {
 880         X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsaEncryption), V_ASN1_NULL, 0);
 881         return 1;
 882     }
 883     /* Not supported */
 884     if (pad_mode != RSA_PKCS1_OAEP_PADDING)
 885         return 0;
 886     if (EVP_PKEY_CTX_get_rsa_oaep_md(pkctx, &md) <= 0)
 887         goto err;
 888     if (EVP_PKEY_CTX_get_rsa_mgf1_md(pkctx, &mgf1md) <= 0)
 889         goto err;
 890     labellen = EVP_PKEY_CTX_get0_rsa_oaep_label(pkctx, &label);
 891     if (labellen < 0)
 892         goto err;
 893     oaep = RSA_OAEP_PARAMS_new();
 894     if (!oaep)
 895         goto err;
 896     if (!rsa_md_to_algor(&oaep->hashFunc, md))
 897         goto err;
 898     if (!rsa_md_to_mgf1(&oaep->maskGenFunc, mgf1md))
 899         goto err;
 900     if (labellen > 0) {
 901         ASN1_OCTET_STRING *los = ASN1_OCTET_STRING_new();
 902         oaep->pSourceFunc = X509_ALGOR_new();
 903         if (!oaep->pSourceFunc)
 904             goto err;
 905         if (!los)
 906             goto err;
 907         if (!ASN1_OCTET_STRING_set(los, label, labellen)) {
 908             ASN1_OCTET_STRING_free(los);
 909             goto err;
 910         }
 911         X509_ALGOR_set0(oaep->pSourceFunc, OBJ_nid2obj(NID_pSpecified),
 912                         V_ASN1_OCTET_STRING, los);
 913     }
 914     /* create string with pss parameter encoding. */
 915     if (!ASN1_item_pack(oaep, ASN1_ITEM_rptr(RSA_OAEP_PARAMS), &os))
 916          goto err;
 917     X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsaesOaep), V_ASN1_SEQUENCE, os);
 918     os = NULL;
 919     rv = 1;
 920  err:
 921     if (oaep)
 922         RSA_OAEP_PARAMS_free(oaep);
 923     if (os)
 924         ASN1_STRING_free(os);
 925     return rv;
 926 }
 927
 928 const EVP_PKEY_ASN1_METHOD rsa_asn1_meths[] = {
 929     {
 930      EVP_PKEY_RSA,
 931      EVP_PKEY_RSA,
 932      ASN1_PKEY_SIGPARAM_NULL,
 933
 934      "RSA",
 935      "OpenSSL RSA method",
 936
 937      rsa_pub_decode,
 938      rsa_pub_encode,
 939      rsa_pub_cmp,
 940      rsa_pub_print,
 941
 942      rsa_priv_decode,
 943      rsa_priv_encode,
 944      rsa_priv_print,
 945
 946      int_rsa_size,
 947      rsa_bits,
 948      rsa_security_bits,
 949
 950      0, 0, 0, 0, 0, 0,
 951
 952      rsa_sig_print,
 953      int_rsa_free,
 954      rsa_pkey_ctrl,
 955      old_rsa_priv_decode,
 956      old_rsa_priv_encode,
 957      rsa_item_verify,
 958      rsa_item_sign},
 959
 960     {
 961      EVP_PKEY_RSA2,
 962      EVP_PKEY_RSA,
 963      ASN1_PKEY_ALIAS}
 964 };