crypto/rsa/rsa_ameth.c

   1 /*
   2  * Copyright 2006-2022 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (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 /*
  11  * RSA low level APIs are deprecated for public use, but still ok for
  12  * internal use.
  13  */
  14 #include "internal/deprecated.h"
  15
  16 #include <stdio.h>
  17 #include "internal/cryptlib.h"
  18 #include <openssl/asn1t.h>
  19 #include <openssl/x509.h>
  20 #include <openssl/bn.h>
  21 #include <openssl/core_names.h>
  22 #include <openssl/param_build.h>
  23 #include "crypto/asn1.h"
  24 #include "crypto/evp.h"
  25 #include "crypto/rsa.h"
  26 #include "rsa_local.h"
  27
  28 /* Set any parameters associated with pkey */
  29 static int rsa_param_encode(const EVP_PKEY *pkey,
  30                             ASN1_STRING **pstr, int *pstrtype)
  31 {
  32     const RSA *rsa = pkey->pkey.rsa;
  33
  34     *pstr = NULL;
  35     /* If RSA it's just NULL type */
  36     if (RSA_test_flags(rsa, RSA_FLAG_TYPE_MASK) != RSA_FLAG_TYPE_RSASSAPSS) {
  37         *pstrtype = V_ASN1_NULL;
  38         return 1;
  39     }
  40     /* If no PSS parameters we omit parameters entirely */
  41     if (rsa->pss == NULL) {
  42         *pstrtype = V_ASN1_UNDEF;
  43         return 1;
  44     }
  45     /* Encode PSS parameters */
  46     if (ASN1_item_pack(rsa->pss, ASN1_ITEM_rptr(RSA_PSS_PARAMS), pstr) == NULL)
  47         return 0;
  48
  49     *pstrtype = V_ASN1_SEQUENCE;
  50     return 1;
  51 }
  52 /* Decode any parameters and set them in RSA structure */
  53 static int rsa_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
  54 {
  55     unsigned char *penc = NULL;
  56     int penclen;
  57     ASN1_STRING *str;
  58     int strtype;
  59
  60     if (!rsa_param_encode(pkey, &str, &strtype))
  61         return 0;
  62     penclen = i2d_RSAPublicKey(pkey->pkey.rsa, &penc);
  63     if (penclen <= 0)
  64         return 0;
  65     if (X509_PUBKEY_set0_param(pk, OBJ_nid2obj(pkey->ameth->pkey_id),
  66                                strtype, str, penc, penclen))
  67         return 1;
  68
  69     OPENSSL_free(penc);
  70     return 0;
  71 }
  72
  73 static int rsa_pub_decode(EVP_PKEY *pkey, const X509_PUBKEY *pubkey)
  74 {
  75     const unsigned char *p;
  76     int pklen;
  77     X509_ALGOR *alg;
  78     RSA *rsa = NULL;
  79
  80     if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, &alg, pubkey))
  81         return 0;
  82     if ((rsa = d2i_RSAPublicKey(NULL, &p, pklen)) == NULL)
  83         return 0;
  84     if (!ossl_rsa_param_decode(rsa, alg)) {
  85         RSA_free(rsa);
  86         return 0;
  87     }
  88
  89     RSA_clear_flags(rsa, RSA_FLAG_TYPE_MASK);
  90     switch (pkey->ameth->pkey_id) {
  91     case EVP_PKEY_RSA:
  92         RSA_set_flags(rsa, RSA_FLAG_TYPE_RSA);
  93         break;
  94     case EVP_PKEY_RSA_PSS:
  95         RSA_set_flags(rsa, RSA_FLAG_TYPE_RSASSAPSS);
  96         break;
  97     default:
  98         /* Leave the type bits zero */
  99         break;
 100     }
 101
 102     if (!EVP_PKEY_assign(pkey, pkey->ameth->pkey_id, rsa)) {
 103         RSA_free(rsa);
 104         return 0;
 105     }
 106     return 1;
 107 }
 108
 109 static int rsa_pub_cmp(const EVP_PKEY *a, const EVP_PKEY *b)
 110 {
 111     /*
 112      * Don't check the public/private key, this is mostly for smart
 113      * cards.
 114      */
 115     if (((RSA_flags(a->pkey.rsa) & RSA_METHOD_FLAG_NO_CHECK))
 116             || (RSA_flags(b->pkey.rsa) & RSA_METHOD_FLAG_NO_CHECK)) {
 117         return 1;
 118     }
 119
 120     if (BN_cmp(b->pkey.rsa->n, a->pkey.rsa->n) != 0
 121         || BN_cmp(b->pkey.rsa->e, a->pkey.rsa->e) != 0)
 122         return 0;
 123     return 1;
 124 }
 125
 126 static int old_rsa_priv_decode(EVP_PKEY *pkey,
 127                                const unsigned char **pder, int derlen)
 128 {
 129     RSA *rsa;
 130
 131     if ((rsa = d2i_RSAPrivateKey(NULL, pder, derlen)) == NULL)
 132         return 0;
 133     EVP_PKEY_assign(pkey, pkey->ameth->pkey_id, rsa);
 134     return 1;
 135 }
 136
 137 static int old_rsa_priv_encode(const EVP_PKEY *pkey, unsigned char **pder)
 138 {
 139     return i2d_RSAPrivateKey(pkey->pkey.rsa, pder);
 140 }
 141
 142 static int rsa_priv_encode(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pkey)
 143 {
 144     unsigned char *rk = NULL;
 145     int rklen;
 146     ASN1_STRING *str;
 147     int strtype;
 148
 149     if (!rsa_param_encode(pkey, &str, &strtype))
 150         return 0;
 151     rklen = i2d_RSAPrivateKey(pkey->pkey.rsa, &rk);
 152
 153     if (rklen <= 0) {
 154         ERR_raise(ERR_LIB_RSA, ERR_R_MALLOC_FAILURE);
 155         ASN1_STRING_free(str);
 156         return 0;
 157     }
 158
 159     if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(pkey->ameth->pkey_id), 0,
 160                          strtype, str, rk, rklen)) {
 161         ERR_raise(ERR_LIB_RSA, ERR_R_MALLOC_FAILURE);
 162         ASN1_STRING_free(str);
 163         return 0;
 164     }
 165
 166     return 1;
 167 }
 168
 169 static int rsa_priv_decode(EVP_PKEY *pkey, const PKCS8_PRIV_KEY_INFO *p8)
 170 {
 171     int ret = 0;
 172     RSA *rsa = ossl_rsa_key_from_pkcs8(p8, NULL, NULL);
 173
 174     if (rsa != NULL) {
 175         ret = 1;
 176         EVP_PKEY_assign(pkey, pkey->ameth->pkey_id, rsa);
 177     }
 178     return ret;
 179 }
 180
 181 static int int_rsa_size(const EVP_PKEY *pkey)
 182 {
 183     return RSA_size(pkey->pkey.rsa);
 184 }
 185
 186 static int rsa_bits(const EVP_PKEY *pkey)
 187 {
 188     return BN_num_bits(pkey->pkey.rsa->n);
 189 }
 190
 191 static int rsa_security_bits(const EVP_PKEY *pkey)
 192 {
 193     return RSA_security_bits(pkey->pkey.rsa);
 194 }
 195
 196 static void int_rsa_free(EVP_PKEY *pkey)
 197 {
 198     RSA_free(pkey->pkey.rsa);
 199 }
 200
 201 static int rsa_pss_param_print(BIO *bp, int pss_key, RSA_PSS_PARAMS *pss,
 202                                int indent)
 203 {
 204     int rv = 0;
 205     X509_ALGOR *maskHash = NULL;
 206
 207     if (!BIO_indent(bp, indent, 128))
 208         goto err;
 209     if (pss_key) {
 210         if (pss == NULL) {
 211             if (BIO_puts(bp, "No PSS parameter restrictions\n") <= 0)
 212                 return 0;
 213             return 1;
 214         } else {
 215             if (BIO_puts(bp, "PSS parameter restrictions:") <= 0)
 216                 return 0;
 217         }
 218     } else if (pss == NULL) {
 219         if (BIO_puts(bp, "(INVALID PSS PARAMETERS)\n") <= 0)
 220             return 0;
 221         return 1;
 222     }
 223     if (BIO_puts(bp, "\n") <= 0)
 224         goto err;
 225     if (pss_key)
 226         indent += 2;
 227     if (!BIO_indent(bp, indent, 128))
 228         goto err;
 229     if (BIO_puts(bp, "Hash Algorithm: ") <= 0)
 230         goto err;
 231
 232     if (pss->hashAlgorithm) {
 233         if (i2a_ASN1_OBJECT(bp, pss->hashAlgorithm->algorithm) <= 0)
 234             goto err;
 235     } else if (BIO_puts(bp, "sha1 (default)") <= 0) {
 236         goto err;
 237     }
 238
 239     if (BIO_puts(bp, "\n") <= 0)
 240         goto err;
 241
 242     if (!BIO_indent(bp, indent, 128))
 243         goto err;
 244
 245     if (BIO_puts(bp, "Mask Algorithm: ") <= 0)
 246         goto err;
 247     if (pss->maskGenAlgorithm) {
 248         if (i2a_ASN1_OBJECT(bp, pss->maskGenAlgorithm->algorithm) <= 0)
 249             goto err;
 250         if (BIO_puts(bp, " with ") <= 0)
 251             goto err;
 252         maskHash = ossl_x509_algor_mgf1_decode(pss->maskGenAlgorithm);
 253         if (maskHash != NULL) {
 254             if (i2a_ASN1_OBJECT(bp, maskHash->algorithm) <= 0)
 255                 goto err;
 256         } else if (BIO_puts(bp, "INVALID") <= 0) {
 257             goto err;
 258         }
 259     } else if (BIO_puts(bp, "mgf1 with sha1 (default)") <= 0) {
 260         goto err;
 261     }
 262     BIO_puts(bp, "\n");
 263
 264     if (!BIO_indent(bp, indent, 128))
 265         goto err;
 266     if (BIO_printf(bp, "%s Salt Length: 0x", pss_key ? "Minimum" : "") <= 0)
 267         goto err;
 268     if (pss->saltLength) {
 269         if (i2a_ASN1_INTEGER(bp, pss->saltLength) <= 0)
 270             goto err;
 271     } else if (BIO_puts(bp, "14 (default)") <= 0) {
 272         goto err;
 273     }
 274     BIO_puts(bp, "\n");
 275
 276     if (!BIO_indent(bp, indent, 128))
 277         goto err;
 278     if (BIO_puts(bp, "Trailer Field: 0x") <= 0)
 279         goto err;
 280     if (pss->trailerField) {
 281         if (i2a_ASN1_INTEGER(bp, pss->trailerField) <= 0)
 282             goto err;
 283     } else if (BIO_puts(bp, "01 (default)") <= 0) {
 284         goto err;
 285     }
 286     BIO_puts(bp, "\n");
 287
 288     rv = 1;
 289
 290  err:
 291     X509_ALGOR_free(maskHash);
 292     return rv;
 293
 294 }
 295
 296 static int pkey_rsa_print(BIO *bp, const EVP_PKEY *pkey, int off, int priv)
 297 {
 298     const RSA *x = pkey->pkey.rsa;
 299     char *str;
 300     const char *s;
 301     int ret = 0, mod_len = 0, ex_primes;
 302
 303     if (x->n != NULL)
 304         mod_len = BN_num_bits(x->n);
 305     ex_primes = sk_RSA_PRIME_INFO_num(x->prime_infos);
 306
 307     if (!BIO_indent(bp, off, 128))
 308         goto err;
 309
 310     if (BIO_printf(bp, "%s ", pkey_is_pss(pkey) ?  "RSA-PSS" : "RSA") <= 0)
 311         goto err;
 312
 313     if (priv && x->d) {
 314         if (BIO_printf(bp, "Private-Key: (%d bit, %d primes)\n",
 315                        mod_len, ex_primes <= 0 ? 2 : ex_primes + 2) <= 0)
 316             goto err;
 317         str = "modulus:";
 318         s = "publicExponent:";
 319     } else {
 320         if (BIO_printf(bp, "Public-Key: (%d bit)\n", mod_len) <= 0)
 321             goto err;
 322         str = "Modulus:";
 323         s = "Exponent:";
 324     }
 325     if (!ASN1_bn_print(bp, str, x->n, NULL, off))
 326         goto err;
 327     if (!ASN1_bn_print(bp, s, x->e, NULL, off))
 328         goto err;
 329     if (priv) {
 330         int i;
 331
 332         if (!ASN1_bn_print(bp, "privateExponent:", x->d, NULL, off))
 333             goto err;
 334         if (!ASN1_bn_print(bp, "prime1:", x->p, NULL, off))
 335             goto err;
 336         if (!ASN1_bn_print(bp, "prime2:", x->q, NULL, off))
 337             goto err;
 338         if (!ASN1_bn_print(bp, "exponent1:", x->dmp1, NULL, off))
 339             goto err;
 340         if (!ASN1_bn_print(bp, "exponent2:", x->dmq1, NULL, off))
 341             goto err;
 342         if (!ASN1_bn_print(bp, "coefficient:", x->iqmp, NULL, off))
 343             goto err;
 344         for (i = 0; i < sk_RSA_PRIME_INFO_num(x->prime_infos); i++) {
 345             /* print multi-prime info */
 346             BIGNUM *bn = NULL;
 347             RSA_PRIME_INFO *pinfo;
 348             int j;
 349
 350             pinfo = sk_RSA_PRIME_INFO_value(x->prime_infos, i);
 351             for (j = 0; j < 3; j++) {
 352                 if (!BIO_indent(bp, off, 128))
 353                     goto err;
 354                 switch (j) {
 355                 case 0:
 356                     if (BIO_printf(bp, "prime%d:", i + 3) <= 0)
 357                         goto err;
 358                     bn = pinfo->r;
 359                     break;
 360                 case 1:
 361                     if (BIO_printf(bp, "exponent%d:", i + 3) <= 0)
 362                         goto err;
 363                     bn = pinfo->d;
 364                     break;
 365                 case 2:
 366                     if (BIO_printf(bp, "coefficient%d:", i + 3) <= 0)
 367                         goto err;
 368                     bn = pinfo->t;
 369                     break;
 370                 default:
 371                     break;
 372                 }
 373                 if (!ASN1_bn_print(bp, "", bn, NULL, off))
 374                     goto err;
 375             }
 376         }
 377     }
 378     if (pkey_is_pss(pkey) && !rsa_pss_param_print(bp, 1, x->pss, off))
 379         goto err;
 380     ret = 1;
 381  err:
 382     return ret;
 383 }
 384
 385 static int rsa_pub_print(BIO *bp, const EVP_PKEY *pkey, int indent,
 386                          ASN1_PCTX *ctx)
 387 {
 388     return pkey_rsa_print(bp, pkey, indent, 0);
 389 }
 390
 391 static int rsa_priv_print(BIO *bp, const EVP_PKEY *pkey, int indent,
 392                           ASN1_PCTX *ctx)
 393 {
 394     return pkey_rsa_print(bp, pkey, indent, 1);
 395 }
 396
 397 static int rsa_sig_print(BIO *bp, const X509_ALGOR *sigalg,
 398                          const ASN1_STRING *sig, int indent, ASN1_PCTX *pctx)
 399 {
 400     if (OBJ_obj2nid(sigalg->algorithm) == EVP_PKEY_RSA_PSS) {
 401         int rv;
 402         RSA_PSS_PARAMS *pss = ossl_rsa_pss_decode(sigalg);
 403
 404         rv = rsa_pss_param_print(bp, 0, pss, indent);
 405         RSA_PSS_PARAMS_free(pss);
 406         if (!rv)
 407             return 0;
 408     } else if (BIO_puts(bp, "\n") <= 0) {
 409         return 0;
 410     }
 411     if (sig)
 412         return X509_signature_dump(bp, sig, indent);
 413     return 1;
 414 }
 415
 416 static int rsa_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2)
 417 {
 418     const EVP_MD *md;
 419     const EVP_MD *mgf1md;
 420     int min_saltlen;
 421
 422     switch (op) {
 423     case ASN1_PKEY_CTRL_DEFAULT_MD_NID:
 424         if (pkey->pkey.rsa->pss != NULL) {
 425             if (!ossl_rsa_pss_get_param(pkey->pkey.rsa->pss, &md, &mgf1md,
 426                                         &min_saltlen)) {
 427                 ERR_raise(ERR_LIB_RSA, ERR_R_INTERNAL_ERROR);
 428                 return 0;
 429             }
 430             *(int *)arg2 = EVP_MD_get_type(md);
 431             /* Return of 2 indicates this MD is mandatory */
 432             return 2;
 433         }
 434         *(int *)arg2 = NID_sha256;
 435         return 1;
 436
 437     default:
 438         return -2;
 439     }
 440 }
 441
 442 /*
 443  * Convert EVP_PKEY_CTX in PSS mode into corresponding algorithm parameter,
 444  * suitable for setting an AlgorithmIdentifier.
 445  */
 446
 447 static RSA_PSS_PARAMS *rsa_ctx_to_pss(EVP_PKEY_CTX *pkctx)
 448 {
 449     const EVP_MD *sigmd, *mgf1md;
 450     EVP_PKEY *pk = EVP_PKEY_CTX_get0_pkey(pkctx);
 451     int saltlen;
 452
 453     if (EVP_PKEY_CTX_get_signature_md(pkctx, &sigmd) <= 0)
 454         return NULL;
 455     if (EVP_PKEY_CTX_get_rsa_mgf1_md(pkctx, &mgf1md) <= 0)
 456         return NULL;
 457     if (EVP_PKEY_CTX_get_rsa_pss_saltlen(pkctx, &saltlen) <= 0)
 458         return NULL;
 459     if (saltlen == -1) {
 460         saltlen = EVP_MD_get_size(sigmd);
 461     } else if (saltlen == -2 || saltlen == -3) {
 462         saltlen = EVP_PKEY_get_size(pk) - EVP_MD_get_size(sigmd) - 2;
 463         if ((EVP_PKEY_get_bits(pk) & 0x7) == 1)
 464             saltlen--;
 465         if (saltlen < 0)
 466             return NULL;
 467     }
 468
 469     return ossl_rsa_pss_params_create(sigmd, mgf1md, saltlen);
 470 }
 471
 472 RSA_PSS_PARAMS *ossl_rsa_pss_params_create(const EVP_MD *sigmd,
 473                                            const EVP_MD *mgf1md, int saltlen)
 474 {
 475     RSA_PSS_PARAMS *pss = RSA_PSS_PARAMS_new();
 476
 477     if (pss == NULL)
 478         goto err;
 479     if (saltlen != 20) {
 480         pss->saltLength = ASN1_INTEGER_new();
 481         if (pss->saltLength == NULL)
 482             goto err;
 483         if (!ASN1_INTEGER_set(pss->saltLength, saltlen))
 484             goto err;
 485     }
 486     if (!ossl_x509_algor_new_from_md(&pss->hashAlgorithm, sigmd))
 487         goto err;
 488     if (mgf1md == NULL)
 489         mgf1md = sigmd;
 490     if (!ossl_x509_algor_md_to_mgf1(&pss->maskGenAlgorithm, mgf1md))
 491         goto err;
 492     if (!ossl_x509_algor_new_from_md(&pss->maskHash, mgf1md))
 493         goto err;
 494     return pss;
 495  err:
 496     RSA_PSS_PARAMS_free(pss);
 497     return NULL;
 498 }
 499
 500 ASN1_STRING *ossl_rsa_ctx_to_pss_string(EVP_PKEY_CTX *pkctx)
 501 {
 502     RSA_PSS_PARAMS *pss = rsa_ctx_to_pss(pkctx);
 503     ASN1_STRING *os;
 504
 505     if (pss == NULL)
 506         return NULL;
 507
 508     os = ASN1_item_pack(pss, ASN1_ITEM_rptr(RSA_PSS_PARAMS), NULL);
 509     RSA_PSS_PARAMS_free(pss);
 510     return os;
 511 }
 512
 513 /*
 514  * From PSS AlgorithmIdentifier set public key parameters. If pkey isn't NULL
 515  * then the EVP_MD_CTX is setup and initialised. If it is NULL parameters are
 516  * passed to pkctx instead.
 517  */
 518
 519 int ossl_rsa_pss_to_ctx(EVP_MD_CTX *ctx, EVP_PKEY_CTX *pkctx,
 520                         const X509_ALGOR *sigalg, EVP_PKEY *pkey)
 521 {
 522     int rv = -1;
 523     int saltlen;
 524     const EVP_MD *mgf1md = NULL, *md = NULL;
 525     RSA_PSS_PARAMS *pss;
 526
 527     /* Sanity check: make sure it is PSS */
 528     if (OBJ_obj2nid(sigalg->algorithm) != EVP_PKEY_RSA_PSS) {
 529         ERR_raise(ERR_LIB_RSA, RSA_R_UNSUPPORTED_SIGNATURE_TYPE);
 530         return -1;
 531     }
 532     /* Decode PSS parameters */
 533     pss = ossl_rsa_pss_decode(sigalg);
 534
 535     if (!ossl_rsa_pss_get_param(pss, &md, &mgf1md, &saltlen)) {
 536         ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_PSS_PARAMETERS);
 537         goto err;
 538     }
 539
 540     /* We have all parameters now set up context */
 541     if (pkey) {
 542         if (!EVP_DigestVerifyInit(ctx, &pkctx, md, NULL, pkey))
 543             goto err;
 544     } else {
 545         const EVP_MD *checkmd;
 546         if (EVP_PKEY_CTX_get_signature_md(pkctx, &checkmd) <= 0)
 547             goto err;
 548         if (EVP_MD_get_type(md) != EVP_MD_get_type(checkmd)) {
 549             ERR_raise(ERR_LIB_RSA, RSA_R_DIGEST_DOES_NOT_MATCH);
 550             goto err;
 551         }
 552     }
 553
 554     if (EVP_PKEY_CTX_set_rsa_padding(pkctx, RSA_PKCS1_PSS_PADDING) <= 0)
 555         goto err;
 556
 557     if (EVP_PKEY_CTX_set_rsa_pss_saltlen(pkctx, saltlen) <= 0)
 558         goto err;
 559
 560     if (EVP_PKEY_CTX_set_rsa_mgf1_md(pkctx, mgf1md) <= 0)
 561         goto err;
 562     /* Carry on */
 563     rv = 1;
 564
 565  err:
 566     RSA_PSS_PARAMS_free(pss);
 567     return rv;
 568 }
 569
 570 static int rsa_pss_verify_param(const EVP_MD **pmd, const EVP_MD **pmgf1md,
 571                                 int *psaltlen, int *ptrailerField)
 572 {
 573     if (psaltlen != NULL && *psaltlen < 0) {
 574         ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_SALT_LENGTH);
 575         return 0;
 576     }
 577     /*
 578      * low-level routines support only trailer field 0xbc (value 1) and
 579      * PKCS#1 says we should reject any other value anyway.
 580      */
 581     if (ptrailerField != NULL && *ptrailerField != 1) {
 582         ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_TRAILER);
 583         return 0;
 584     }
 585     return 1;
 586 }
 587
 588 int ossl_rsa_pss_get_param(const RSA_PSS_PARAMS *pss, const EVP_MD **pmd,
 589                            const EVP_MD **pmgf1md, int *psaltlen)
 590 {
 591     /*
 592      * Callers do not care about the trailer field, and yet, we must
 593      * pass it from get_param to verify_param, since the latter checks
 594      * its value.
 595      *
 596      * When callers start caring, it's a simple thing to add another
 597      * argument to this function.
 598      */
 599     int trailerField = 0;
 600
 601     return ossl_rsa_pss_get_param_unverified(pss, pmd, pmgf1md, psaltlen,
 602                                              &trailerField)
 603         && rsa_pss_verify_param(pmd, pmgf1md, psaltlen, &trailerField);
 604 }
 605
 606 /*
 607  * Customised RSA item verification routine. This is called when a signature
 608  * is encountered requiring special handling. We currently only handle PSS.
 609  */
 610
 611 static int rsa_item_verify(EVP_MD_CTX *ctx, const ASN1_ITEM *it,
 612                            const void *asn, const X509_ALGOR *sigalg,
 613                            const ASN1_BIT_STRING *sig, EVP_PKEY *pkey)
 614 {
 615     /* Sanity check: make sure it is PSS */
 616     if (OBJ_obj2nid(sigalg->algorithm) != EVP_PKEY_RSA_PSS) {
 617         ERR_raise(ERR_LIB_RSA, RSA_R_UNSUPPORTED_SIGNATURE_TYPE);
 618         return -1;
 619     }
 620     if (ossl_rsa_pss_to_ctx(ctx, NULL, sigalg, pkey) > 0) {
 621         /* Carry on */
 622         return 2;
 623     }
 624     return -1;
 625 }
 626
 627 static int rsa_item_sign(EVP_MD_CTX *ctx, const ASN1_ITEM *it, const void *asn,
 628                          X509_ALGOR *alg1, X509_ALGOR *alg2,
 629                          ASN1_BIT_STRING *sig)
 630 {
 631     int pad_mode;
 632     EVP_PKEY_CTX *pkctx = EVP_MD_CTX_get_pkey_ctx(ctx);
 633
 634     if (EVP_PKEY_CTX_get_rsa_padding(pkctx, &pad_mode) <= 0)
 635         return 0;
 636     if (pad_mode == RSA_PKCS1_PADDING)
 637         return 2;
 638     if (pad_mode == RSA_PKCS1_PSS_PADDING) {
 639         ASN1_STRING *os1 = ossl_rsa_ctx_to_pss_string(pkctx);
 640
 641         if (os1 == NULL)
 642             return 0;
 643         /* Duplicate parameters if we have to */
 644         if (alg2 != NULL) {
 645             ASN1_STRING *os2 = ASN1_STRING_dup(os1);
 646
 647             if (os2 == NULL)
 648                 goto err;
 649             if (!X509_ALGOR_set0(alg2, OBJ_nid2obj(EVP_PKEY_RSA_PSS),
 650                                  V_ASN1_SEQUENCE, os2)) {
 651                 ASN1_STRING_free(os2);
 652                 goto err;
 653             }
 654         }
 655         if (!X509_ALGOR_set0(alg1, OBJ_nid2obj(EVP_PKEY_RSA_PSS),
 656                              V_ASN1_SEQUENCE, os1))
 657             goto err;
 658         return 3;
 659     err:
 660         ASN1_STRING_free(os1);
 661         return 0;
 662     }
 663     return 2;
 664 }
 665
 666 static int rsa_sig_info_set(X509_SIG_INFO *siginf, const X509_ALGOR *sigalg,
 667                             const ASN1_STRING *sig)
 668 {
 669     int rv = 0;
 670     int mdnid, saltlen;
 671     uint32_t flags;
 672     const EVP_MD *mgf1md = NULL, *md = NULL;
 673     RSA_PSS_PARAMS *pss;
 674     int secbits;
 675
 676     /* Sanity check: make sure it is PSS */
 677     if (OBJ_obj2nid(sigalg->algorithm) != EVP_PKEY_RSA_PSS)
 678         return 0;
 679     /* Decode PSS parameters */
 680     pss = ossl_rsa_pss_decode(sigalg);
 681     if (!ossl_rsa_pss_get_param(pss, &md, &mgf1md, &saltlen))
 682         goto err;
 683     mdnid = EVP_MD_get_type(md);
 684     /*
 685      * For TLS need SHA256, SHA384 or SHA512, digest and MGF1 digest must
 686      * match and salt length must equal digest size
 687      */
 688     if ((mdnid == NID_sha256 || mdnid == NID_sha384 || mdnid == NID_sha512)
 689             && mdnid == EVP_MD_get_type(mgf1md)
 690             && saltlen == EVP_MD_get_size(md))
 691         flags = X509_SIG_INFO_TLS;
 692     else
 693         flags = 0;
 694     /* Note: security bits half number of digest bits */
 695     secbits = EVP_MD_get_size(md) * 4;
 696     /*
 697      * SHA1 and MD5 are known to be broken. Reduce security bits so that
 698      * they're no longer accepted at security level 1. The real values don't
 699      * really matter as long as they're lower than 80, which is our security
 700      * level 1.
 701      * https://eprint.iacr.org/2020/014 puts a chosen-prefix attack for SHA1 at
 702      * 2^63.4
 703      * https://documents.epfl.ch/users/l/le/lenstra/public/papers/lat.pdf
 704      * puts a chosen-prefix attack for MD5 at 2^39.
 705      */
 706     if (mdnid == NID_sha1)
 707         secbits = 64;
 708     else if (mdnid == NID_md5_sha1)
 709         secbits = 68;
 710     else if (mdnid == NID_md5)
 711         secbits = 39;
 712     X509_SIG_INFO_set(siginf, mdnid, EVP_PKEY_RSA_PSS, secbits,
 713                       flags);
 714     rv = 1;
 715     err:
 716     RSA_PSS_PARAMS_free(pss);
 717     return rv;
 718 }
 719
 720 static int rsa_pkey_check(const EVP_PKEY *pkey)
 721 {
 722     return RSA_check_key_ex(pkey->pkey.rsa, NULL);
 723 }
 724
 725 static size_t rsa_pkey_dirty_cnt(const EVP_PKEY *pkey)
 726 {
 727     return pkey->pkey.rsa->dirty_cnt;
 728 }
 729
 730 /*
 731  * There is no need to do RSA_test_flags(rsa, RSA_FLAG_TYPE_RSASSAPSS)
 732  * checks in this method since the caller tests EVP_KEYMGMT_is_a() first.
 733  */
 734 static int rsa_int_export_to(const EVP_PKEY *from, int rsa_type,
 735                              void *to_keydata,
 736                              OSSL_FUNC_keymgmt_import_fn *importer,
 737                              OSSL_LIB_CTX *libctx, const char *propq)
 738 {
 739     RSA *rsa = from->pkey.rsa;
 740     OSSL_PARAM_BLD *tmpl = OSSL_PARAM_BLD_new();
 741     OSSL_PARAM *params = NULL;
 742     int selection = 0;
 743     int rv = 0;
 744
 745     if (tmpl == NULL)
 746         return 0;
 747     /* Public parameters must always be present */
 748     if (RSA_get0_n(rsa) == NULL || RSA_get0_e(rsa) == NULL)
 749         goto err;
 750
 751     if (!ossl_rsa_todata(rsa, tmpl, NULL, 1))
 752         goto err;
 753
 754     selection |= OSSL_KEYMGMT_SELECT_PUBLIC_KEY;
 755     if (RSA_get0_d(rsa) != NULL)
 756         selection |= OSSL_KEYMGMT_SELECT_PRIVATE_KEY;
 757
 758     if (rsa->pss != NULL) {
 759         const EVP_MD *md = NULL, *mgf1md = NULL;
 760         int md_nid, mgf1md_nid, saltlen, trailerfield;
 761         RSA_PSS_PARAMS_30 pss_params;
 762
 763         if (!ossl_rsa_pss_get_param_unverified(rsa->pss, &md, &mgf1md,
 764                                                &saltlen, &trailerfield))
 765             goto err;
 766         md_nid = EVP_MD_get_type(md);
 767         mgf1md_nid = EVP_MD_get_type(mgf1md);
 768         if (!ossl_rsa_pss_params_30_set_defaults(&pss_params)
 769             || !ossl_rsa_pss_params_30_set_hashalg(&pss_params, md_nid)
 770             || !ossl_rsa_pss_params_30_set_maskgenhashalg(&pss_params,
 771                                                           mgf1md_nid)
 772             || !ossl_rsa_pss_params_30_set_saltlen(&pss_params, saltlen)
 773             || !ossl_rsa_pss_params_30_todata(&pss_params, tmpl, NULL))
 774             goto err;
 775         selection |= OSSL_KEYMGMT_SELECT_OTHER_PARAMETERS;
 776     }
 777
 778     if ((params = OSSL_PARAM_BLD_to_param(tmpl)) == NULL)
 779         goto err;
 780
 781     /* We export, the provider imports */
 782     rv = importer(to_keydata, selection, params);
 783
 784  err:
 785     OSSL_PARAM_free(params);
 786     OSSL_PARAM_BLD_free(tmpl);
 787     return rv;
 788 }
 789
 790 static int rsa_int_import_from(const OSSL_PARAM params[], void *vpctx,
 791                                int rsa_type)
 792 {
 793     EVP_PKEY_CTX *pctx = vpctx;
 794     EVP_PKEY *pkey = EVP_PKEY_CTX_get0_pkey(pctx);
 795     RSA *rsa = ossl_rsa_new_with_ctx(pctx->libctx);
 796     RSA_PSS_PARAMS_30 rsa_pss_params = { 0, };
 797     int pss_defaults_set = 0;
 798     int ok = 0;
 799
 800     if (rsa == NULL) {
 801         ERR_raise(ERR_LIB_DH, ERR_R_MALLOC_FAILURE);
 802         return 0;
 803     }
 804
 805     RSA_clear_flags(rsa, RSA_FLAG_TYPE_MASK);
 806     RSA_set_flags(rsa, rsa_type);
 807
 808     if (!ossl_rsa_pss_params_30_fromdata(&rsa_pss_params, &pss_defaults_set,
 809                                          params, pctx->libctx))
 810         goto err;
 811
 812     switch (rsa_type) {
 813     case RSA_FLAG_TYPE_RSA:
 814         /*
 815          * Were PSS parameters filled in?
 816          * In that case, something's wrong
 817          */
 818         if (!ossl_rsa_pss_params_30_is_unrestricted(&rsa_pss_params))
 819             goto err;
 820         break;
 821     case RSA_FLAG_TYPE_RSASSAPSS:
 822         /*
 823          * Were PSS parameters filled in?  In that case, create the old
 824          * RSA_PSS_PARAMS structure.  Otherwise, this is an unrestricted key.
 825          */
 826         if (!ossl_rsa_pss_params_30_is_unrestricted(&rsa_pss_params)) {
 827             /* Create the older RSA_PSS_PARAMS from RSA_PSS_PARAMS_30 data */
 828             int mdnid = ossl_rsa_pss_params_30_hashalg(&rsa_pss_params);
 829             int mgf1mdnid = ossl_rsa_pss_params_30_maskgenhashalg(&rsa_pss_params);
 830             int saltlen = ossl_rsa_pss_params_30_saltlen(&rsa_pss_params);
 831             const EVP_MD *md = EVP_get_digestbynid(mdnid);
 832             const EVP_MD *mgf1md = EVP_get_digestbynid(mgf1mdnid);
 833
 834             if ((rsa->pss = ossl_rsa_pss_params_create(md, mgf1md,
 835                                                        saltlen)) == NULL)
 836                 goto err;
 837         }
 838         break;
 839     default:
 840         /* RSA key sub-types we don't know how to handle yet */
 841         goto err;
 842     }
 843
 844     if (!ossl_rsa_fromdata(rsa, params, 1))
 845         goto err;
 846
 847     switch (rsa_type) {
 848     case RSA_FLAG_TYPE_RSA:
 849         ok = EVP_PKEY_assign_RSA(pkey, rsa);
 850         break;
 851     case RSA_FLAG_TYPE_RSASSAPSS:
 852         ok = EVP_PKEY_assign(pkey, EVP_PKEY_RSA_PSS, rsa);
 853         break;
 854     }
 855
 856  err:
 857     if (!ok)
 858         RSA_free(rsa);
 859     return ok;
 860 }
 861
 862 static int rsa_pkey_export_to(const EVP_PKEY *from, void *to_keydata,
 863                               OSSL_FUNC_keymgmt_import_fn *importer,
 864                               OSSL_LIB_CTX *libctx, const char *propq)
 865 {
 866     return rsa_int_export_to(from, RSA_FLAG_TYPE_RSA, to_keydata,
 867                              importer, libctx, propq);
 868 }
 869
 870 static int rsa_pss_pkey_export_to(const EVP_PKEY *from, void *to_keydata,
 871                                   OSSL_FUNC_keymgmt_import_fn *importer,
 872                                   OSSL_LIB_CTX *libctx, const char *propq)
 873 {
 874     return rsa_int_export_to(from, RSA_FLAG_TYPE_RSASSAPSS, to_keydata,
 875                              importer, libctx, propq);
 876 }
 877
 878 static int rsa_pkey_import_from(const OSSL_PARAM params[], void *vpctx)
 879 {
 880     return rsa_int_import_from(params, vpctx, RSA_FLAG_TYPE_RSA);
 881 }
 882
 883 static int rsa_pss_pkey_import_from(const OSSL_PARAM params[], void *vpctx)
 884 {
 885     return rsa_int_import_from(params, vpctx, RSA_FLAG_TYPE_RSASSAPSS);
 886 }
 887
 888 static int rsa_pkey_copy(EVP_PKEY *to, EVP_PKEY *from)
 889 {
 890     RSA *rsa = from->pkey.rsa;
 891     RSA *dupkey = NULL;
 892     int ret;
 893
 894     if (rsa != NULL) {
 895         dupkey = ossl_rsa_dup(rsa, OSSL_KEYMGMT_SELECT_ALL);
 896         if (dupkey == NULL)
 897             return 0;
 898     }
 899
 900     ret = EVP_PKEY_assign(to, from->type, dupkey);
 901     if (!ret)
 902         RSA_free(dupkey);
 903     return ret;
 904 }
 905
 906 const EVP_PKEY_ASN1_METHOD ossl_rsa_asn1_meths[2] = {
 907     {
 908      EVP_PKEY_RSA,
 909      EVP_PKEY_RSA,
 910      ASN1_PKEY_SIGPARAM_NULL,
 911
 912      "RSA",
 913      "OpenSSL RSA method",
 914
 915      rsa_pub_decode,
 916      rsa_pub_encode,
 917      rsa_pub_cmp,
 918      rsa_pub_print,
 919
 920      rsa_priv_decode,
 921      rsa_priv_encode,
 922      rsa_priv_print,
 923
 924      int_rsa_size,
 925      rsa_bits,
 926      rsa_security_bits,
 927
 928      0, 0, 0, 0, 0, 0,
 929
 930      rsa_sig_print,
 931      int_rsa_free,
 932      rsa_pkey_ctrl,
 933      old_rsa_priv_decode,
 934      old_rsa_priv_encode,
 935      rsa_item_verify,
 936      rsa_item_sign,
 937      rsa_sig_info_set,
 938      rsa_pkey_check,
 939
 940      0, 0,
 941      0, 0, 0, 0,
 942
 943      rsa_pkey_dirty_cnt,
 944      rsa_pkey_export_to,
 945      rsa_pkey_import_from,
 946      rsa_pkey_copy
 947     },
 948
 949     {
 950      EVP_PKEY_RSA2,
 951      EVP_PKEY_RSA,
 952      ASN1_PKEY_ALIAS}
 953 };
 954
 955 const EVP_PKEY_ASN1_METHOD ossl_rsa_pss_asn1_meth = {
 956      EVP_PKEY_RSA_PSS,
 957      EVP_PKEY_RSA_PSS,
 958      ASN1_PKEY_SIGPARAM_NULL,
 959
 960      "RSA-PSS",
 961      "OpenSSL RSA-PSS method",
 962
 963      rsa_pub_decode,
 964      rsa_pub_encode,
 965      rsa_pub_cmp,
 966      rsa_pub_print,
 967
 968      rsa_priv_decode,
 969      rsa_priv_encode,
 970      rsa_priv_print,
 971
 972      int_rsa_size,
 973      rsa_bits,
 974      rsa_security_bits,
 975
 976      0, 0, 0, 0, 0, 0,
 977
 978      rsa_sig_print,
 979      int_rsa_free,
 980      rsa_pkey_ctrl,
 981      0, 0,
 982      rsa_item_verify,
 983      rsa_item_sign,
 984      rsa_sig_info_set,
 985      rsa_pkey_check,
 986
 987      0, 0,
 988      0, 0, 0, 0,
 989
 990      rsa_pkey_dirty_cnt,
 991      rsa_pss_pkey_export_to,
 992      rsa_pss_pkey_import_from,
 993      rsa_pkey_copy
 994 };