crypto/rsa/rsa_pmeth.c

   1 /*
   2  * Copyright 2006-2021 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 "internal/constant_time.h"
  17
  18 #include <stdio.h>
  19 #include "internal/cryptlib.h"
  20 #include <openssl/asn1t.h>
  21 #include <openssl/x509.h>
  22 #include <openssl/rsa.h>
  23 #include <openssl/bn.h>
  24 #include <openssl/evp.h>
  25 #include <openssl/x509v3.h>
  26 #include <openssl/cms.h>
  27 #include "crypto/evp.h"
  28 #include "crypto/rsa.h"
  29 #include "rsa_local.h"
  30
  31 /* RSA pkey context structure */
  32
  33 typedef struct {
  34     /* Key gen parameters */
  35     int nbits;
  36     BIGNUM *pub_exp;
  37     int primes;
  38     /* Keygen callback info */
  39     int gentmp[2];
  40     /* RSA padding mode */
  41     int pad_mode;
  42     /* message digest */
  43     const EVP_MD *md;
  44     /* message digest for MGF1 */
  45     const EVP_MD *mgf1md;
  46     /* PSS salt length */
  47     int saltlen;
  48     /* Minimum salt length or -1 if no PSS parameter restriction */
  49     int min_saltlen;
  50     /* Temp buffer */
  51     unsigned char *tbuf;
  52     /* OAEP label */
  53     unsigned char *oaep_label;
  54     size_t oaep_labellen;
  55 } RSA_PKEY_CTX;
  56
  57 /* True if PSS parameters are restricted */
  58 #define rsa_pss_restricted(rctx) (rctx->min_saltlen != -1)
  59
  60 static int pkey_rsa_init(EVP_PKEY_CTX *ctx)
  61 {
  62     RSA_PKEY_CTX *rctx = OPENSSL_zalloc(sizeof(*rctx));
  63
  64     if (rctx == NULL)
  65         return 0;
  66     rctx->nbits = 2048;
  67     rctx->primes = RSA_DEFAULT_PRIME_NUM;
  68     if (pkey_ctx_is_pss(ctx))
  69         rctx->pad_mode = RSA_PKCS1_PSS_PADDING;
  70     else
  71         rctx->pad_mode = RSA_PKCS1_PADDING;
  72     /* Maximum for sign, auto for verify */
  73     rctx->saltlen = RSA_PSS_SALTLEN_AUTO;
  74     rctx->min_saltlen = -1;
  75     ctx->data = rctx;
  76     ctx->keygen_info = rctx->gentmp;
  77     ctx->keygen_info_count = 2;
  78
  79     return 1;
  80 }
  81
  82 static int pkey_rsa_copy(EVP_PKEY_CTX *dst, const EVP_PKEY_CTX *src)
  83 {
  84     RSA_PKEY_CTX *dctx, *sctx;
  85
  86     if (!pkey_rsa_init(dst))
  87         return 0;
  88     sctx = src->data;
  89     dctx = dst->data;
  90     dctx->nbits = sctx->nbits;
  91     if (sctx->pub_exp) {
  92         dctx->pub_exp = BN_dup(sctx->pub_exp);
  93         if (!dctx->pub_exp)
  94             return 0;
  95     }
  96     dctx->pad_mode = sctx->pad_mode;
  97     dctx->md = sctx->md;
  98     dctx->mgf1md = sctx->mgf1md;
  99     dctx->saltlen = sctx->saltlen;
 100     if (sctx->oaep_label) {
 101         OPENSSL_free(dctx->oaep_label);
 102         dctx->oaep_label = OPENSSL_memdup(sctx->oaep_label, sctx->oaep_labellen);
 103         if (!dctx->oaep_label)
 104             return 0;
 105         dctx->oaep_labellen = sctx->oaep_labellen;
 106     }
 107     return 1;
 108 }
 109
 110 static int setup_tbuf(RSA_PKEY_CTX *ctx, EVP_PKEY_CTX *pk)
 111 {
 112     if (ctx->tbuf != NULL)
 113         return 1;
 114     if ((ctx->tbuf =
 115             OPENSSL_malloc(RSA_size(EVP_PKEY_get0_RSA(pk->pkey)))) == NULL) {
 116         ERR_raise(ERR_LIB_RSA, ERR_R_MALLOC_FAILURE);
 117         return 0;
 118     }
 119     return 1;
 120 }
 121
 122 static void pkey_rsa_cleanup(EVP_PKEY_CTX *ctx)
 123 {
 124     RSA_PKEY_CTX *rctx = ctx->data;
 125     if (rctx) {
 126         BN_free(rctx->pub_exp);
 127         OPENSSL_free(rctx->tbuf);
 128         OPENSSL_free(rctx->oaep_label);
 129         OPENSSL_free(rctx);
 130     }
 131 }
 132
 133 static int pkey_rsa_sign(EVP_PKEY_CTX *ctx, unsigned char *sig,
 134                          size_t *siglen, const unsigned char *tbs,
 135                          size_t tbslen)
 136 {
 137     int ret;
 138     RSA_PKEY_CTX *rctx = ctx->data;
 139     /*
 140      * Discard const. Its marked as const because this may be a cached copy of
 141      * the "real" key. These calls don't make any modifications that need to
 142      * be reflected back in the "original" key.
 143      */
 144     RSA *rsa = (RSA *)EVP_PKEY_get0_RSA(ctx->pkey);
 145
 146     if (rctx->md) {
 147         if (tbslen != (size_t)EVP_MD_get_size(rctx->md)) {
 148             ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_DIGEST_LENGTH);
 149             return -1;
 150         }
 151
 152         if (EVP_MD_get_type(rctx->md) == NID_mdc2) {
 153             unsigned int sltmp;
 154             if (rctx->pad_mode != RSA_PKCS1_PADDING)
 155                 return -1;
 156             ret = RSA_sign_ASN1_OCTET_STRING(0, tbs, tbslen, sig, &sltmp, rsa);
 157
 158             if (ret <= 0)
 159                 return ret;
 160             ret = sltmp;
 161         } else if (rctx->pad_mode == RSA_X931_PADDING) {
 162             if ((size_t)RSA_size(rsa) < tbslen + 1) {
 163                 ERR_raise(ERR_LIB_RSA, RSA_R_KEY_SIZE_TOO_SMALL);
 164                 return -1;
 165             }
 166             if (!setup_tbuf(rctx, ctx)) {
 167                 ERR_raise(ERR_LIB_RSA, ERR_R_MALLOC_FAILURE);
 168                 return -1;
 169             }
 170             memcpy(rctx->tbuf, tbs, tbslen);
 171             rctx->tbuf[tbslen] = RSA_X931_hash_id(EVP_MD_get_type(rctx->md));
 172             ret = RSA_private_encrypt(tbslen + 1, rctx->tbuf,
 173                                       sig, rsa, RSA_X931_PADDING);
 174         } else if (rctx->pad_mode == RSA_PKCS1_PADDING) {
 175             unsigned int sltmp;
 176             ret = RSA_sign(EVP_MD_get_type(rctx->md),
 177                            tbs, tbslen, sig, &sltmp, rsa);
 178             if (ret <= 0)
 179                 return ret;
 180             ret = sltmp;
 181         } else if (rctx->pad_mode == RSA_PKCS1_PSS_PADDING) {
 182             if (!setup_tbuf(rctx, ctx))
 183                 return -1;
 184             if (!RSA_padding_add_PKCS1_PSS_mgf1(rsa,
 185                                                 rctx->tbuf, tbs,
 186                                                 rctx->md, rctx->mgf1md,
 187                                                 rctx->saltlen))
 188                 return -1;
 189             ret = RSA_private_encrypt(RSA_size(rsa), rctx->tbuf,
 190                                       sig, rsa, RSA_NO_PADDING);
 191         } else {
 192             return -1;
 193         }
 194     } else {
 195         ret = RSA_private_encrypt(tbslen, tbs, sig, rsa, rctx->pad_mode);
 196     }
 197     if (ret < 0)
 198         return ret;
 199     *siglen = ret;
 200     return 1;
 201 }
 202
 203 static int pkey_rsa_verifyrecover(EVP_PKEY_CTX *ctx,
 204                                   unsigned char *rout, size_t *routlen,
 205                                   const unsigned char *sig, size_t siglen)
 206 {
 207     int ret;
 208     RSA_PKEY_CTX *rctx = ctx->data;
 209     /*
 210      * Discard const. Its marked as const because this may be a cached copy of
 211      * the "real" key. These calls don't make any modifications that need to
 212      * be reflected back in the "original" key.
 213      */
 214     RSA *rsa = (RSA *)EVP_PKEY_get0_RSA(ctx->pkey);
 215
 216     if (rctx->md) {
 217         if (rctx->pad_mode == RSA_X931_PADDING) {
 218             if (!setup_tbuf(rctx, ctx))
 219                 return -1;
 220             ret = RSA_public_decrypt(siglen, sig, rctx->tbuf, rsa,
 221                                      RSA_X931_PADDING);
 222             if (ret < 1)
 223                 return 0;
 224             ret--;
 225             if (rctx->tbuf[ret] != RSA_X931_hash_id(EVP_MD_get_type(rctx->md))) {
 226                 ERR_raise(ERR_LIB_RSA, RSA_R_ALGORITHM_MISMATCH);
 227                 return 0;
 228             }
 229             if (ret != EVP_MD_get_size(rctx->md)) {
 230                 ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_DIGEST_LENGTH);
 231                 return 0;
 232             }
 233             if (rout)
 234                 memcpy(rout, rctx->tbuf, ret);
 235         } else if (rctx->pad_mode == RSA_PKCS1_PADDING) {
 236             size_t sltmp;
 237             ret = ossl_rsa_verify(EVP_MD_get_type(rctx->md),
 238                                   NULL, 0, rout, &sltmp,
 239                                   sig, siglen, rsa);
 240             if (ret <= 0)
 241                 return 0;
 242             ret = sltmp;
 243         } else {
 244             return -1;
 245         }
 246     } else {
 247         ret = RSA_public_decrypt(siglen, sig, rout, rsa, rctx->pad_mode);
 248     }
 249     if (ret < 0)
 250         return ret;
 251     *routlen = ret;
 252     return 1;
 253 }
 254
 255 static int pkey_rsa_verify(EVP_PKEY_CTX *ctx,
 256                            const unsigned char *sig, size_t siglen,
 257                            const unsigned char *tbs, size_t tbslen)
 258 {
 259     RSA_PKEY_CTX *rctx = ctx->data;
 260     /*
 261      * Discard const. Its marked as const because this may be a cached copy of
 262      * the "real" key. These calls don't make any modifications that need to
 263      * be reflected back in the "original" key.
 264      */
 265     RSA *rsa = (RSA *)EVP_PKEY_get0_RSA(ctx->pkey);
 266     size_t rslen;
 267
 268     if (rctx->md) {
 269         if (rctx->pad_mode == RSA_PKCS1_PADDING)
 270             return RSA_verify(EVP_MD_get_type(rctx->md), tbs, tbslen,
 271                               sig, siglen, rsa);
 272         if (tbslen != (size_t)EVP_MD_get_size(rctx->md)) {
 273             ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_DIGEST_LENGTH);
 274             return -1;
 275         }
 276         if (rctx->pad_mode == RSA_X931_PADDING) {
 277             if (pkey_rsa_verifyrecover(ctx, NULL, &rslen, sig, siglen) <= 0)
 278                 return 0;
 279         } else if (rctx->pad_mode == RSA_PKCS1_PSS_PADDING) {
 280             int ret;
 281             if (!setup_tbuf(rctx, ctx))
 282                 return -1;
 283             ret = RSA_public_decrypt(siglen, sig, rctx->tbuf,
 284                                      rsa, RSA_NO_PADDING);
 285             if (ret <= 0)
 286                 return 0;
 287             ret = RSA_verify_PKCS1_PSS_mgf1(rsa, tbs,
 288                                             rctx->md, rctx->mgf1md,
 289                                             rctx->tbuf, rctx->saltlen);
 290             if (ret <= 0)
 291                 return 0;
 292             return 1;
 293         } else {
 294             return -1;
 295         }
 296     } else {
 297         if (!setup_tbuf(rctx, ctx))
 298             return -1;
 299         rslen = RSA_public_decrypt(siglen, sig, rctx->tbuf,
 300                                    rsa, rctx->pad_mode);
 301         if (rslen == 0)
 302             return 0;
 303     }
 304
 305     if ((rslen != tbslen) || memcmp(tbs, rctx->tbuf, rslen))
 306         return 0;
 307
 308     return 1;
 309
 310 }
 311
 312 static int pkey_rsa_encrypt(EVP_PKEY_CTX *ctx,
 313                             unsigned char *out, size_t *outlen,
 314                             const unsigned char *in, size_t inlen)
 315 {
 316     int ret;
 317     RSA_PKEY_CTX *rctx = ctx->data;
 318     /*
 319      * Discard const. Its marked as const because this may be a cached copy of
 320      * the "real" key. These calls don't make any modifications that need to
 321      * be reflected back in the "original" key.
 322      */
 323     RSA *rsa = (RSA *)EVP_PKEY_get0_RSA(ctx->pkey);
 324
 325     if (rctx->pad_mode == RSA_PKCS1_OAEP_PADDING) {
 326         int klen = RSA_size(rsa);
 327         if (!setup_tbuf(rctx, ctx))
 328             return -1;
 329         if (!RSA_padding_add_PKCS1_OAEP_mgf1(rctx->tbuf, klen,
 330                                              in, inlen,
 331                                              rctx->oaep_label,
 332                                              rctx->oaep_labellen,
 333                                              rctx->md, rctx->mgf1md))
 334             return -1;
 335         ret = RSA_public_encrypt(klen, rctx->tbuf, out, rsa, RSA_NO_PADDING);
 336     } else {
 337         ret = RSA_public_encrypt(inlen, in, out, rsa, rctx->pad_mode);
 338     }
 339     if (ret < 0)
 340         return ret;
 341     *outlen = ret;
 342     return 1;
 343 }
 344
 345 static int pkey_rsa_decrypt(EVP_PKEY_CTX *ctx,
 346                             unsigned char *out, size_t *outlen,
 347                             const unsigned char *in, size_t inlen)
 348 {
 349     int ret;
 350     RSA_PKEY_CTX *rctx = ctx->data;
 351     /*
 352      * Discard const. Its marked as const because this may be a cached copy of
 353      * the "real" key. These calls don't make any modifications that need to
 354      * be reflected back in the "original" key.
 355      */
 356     RSA *rsa = (RSA *)EVP_PKEY_get0_RSA(ctx->pkey);
 357
 358     if (rctx->pad_mode == RSA_PKCS1_OAEP_PADDING) {
 359         if (!setup_tbuf(rctx, ctx))
 360             return -1;
 361         ret = RSA_private_decrypt(inlen, in, rctx->tbuf, rsa, RSA_NO_PADDING);
 362         if (ret <= 0)
 363             return ret;
 364         ret = RSA_padding_check_PKCS1_OAEP_mgf1(out, ret, rctx->tbuf,
 365                                                 ret, ret,
 366                                                 rctx->oaep_label,
 367                                                 rctx->oaep_labellen,
 368                                                 rctx->md, rctx->mgf1md);
 369     } else {
 370         ret = RSA_private_decrypt(inlen, in, out, rsa, rctx->pad_mode);
 371     }
 372     *outlen = constant_time_select_s(constant_time_msb_s(ret), *outlen, ret);
 373     ret = constant_time_select_int(constant_time_msb(ret), ret, 1);
 374     return ret;
 375 }
 376
 377 static int check_padding_md(const EVP_MD *md, int padding)
 378 {
 379     int mdnid;
 380
 381     if (!md)
 382         return 1;
 383
 384     mdnid = EVP_MD_get_type(md);
 385
 386     if (padding == RSA_NO_PADDING) {
 387         ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_PADDING_MODE);
 388         return 0;
 389     }
 390
 391     if (padding == RSA_X931_PADDING) {
 392         if (RSA_X931_hash_id(mdnid) == -1) {
 393             ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_X931_DIGEST);
 394             return 0;
 395         }
 396     } else {
 397         switch (mdnid) {
 398         /* List of all supported RSA digests */
 399         case NID_sha1:
 400         case NID_sha224:
 401         case NID_sha256:
 402         case NID_sha384:
 403         case NID_sha512:
 404         case NID_sha512_224:
 405         case NID_sha512_256:
 406         case NID_md5:
 407         case NID_md5_sha1:
 408         case NID_md2:
 409         case NID_md4:
 410         case NID_mdc2:
 411         case NID_ripemd160:
 412         case NID_sha3_224:
 413         case NID_sha3_256:
 414         case NID_sha3_384:
 415         case NID_sha3_512:
 416             return 1;
 417
 418         default:
 419             ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_DIGEST);
 420             return 0;
 421
 422         }
 423     }
 424
 425     return 1;
 426 }
 427
 428 static int pkey_rsa_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
 429 {
 430     RSA_PKEY_CTX *rctx = ctx->data;
 431
 432     switch (type) {
 433     case EVP_PKEY_CTRL_RSA_PADDING:
 434         if ((p1 >= RSA_PKCS1_PADDING) && (p1 <= RSA_PKCS1_PSS_PADDING)) {
 435             if (!check_padding_md(rctx->md, p1))
 436                 return 0;
 437             if (p1 == RSA_PKCS1_PSS_PADDING) {
 438                 if (!(ctx->operation &
 439                       (EVP_PKEY_OP_SIGN | EVP_PKEY_OP_VERIFY)))
 440                     goto bad_pad;
 441                 if (!rctx->md)
 442                     rctx->md = EVP_sha1();
 443             } else if (pkey_ctx_is_pss(ctx)) {
 444                 goto bad_pad;
 445             }
 446             if (p1 == RSA_PKCS1_OAEP_PADDING) {
 447                 if (!(ctx->operation & EVP_PKEY_OP_TYPE_CRYPT))
 448                     goto bad_pad;
 449                 if (!rctx->md)
 450                     rctx->md = EVP_sha1();
 451             }
 452             rctx->pad_mode = p1;
 453             return 1;
 454         }
 455  bad_pad:
 456         ERR_raise(ERR_LIB_RSA, RSA_R_ILLEGAL_OR_UNSUPPORTED_PADDING_MODE);
 457         return -2;
 458
 459     case EVP_PKEY_CTRL_GET_RSA_PADDING:
 460         *(int *)p2 = rctx->pad_mode;
 461         return 1;
 462
 463     case EVP_PKEY_CTRL_RSA_PSS_SALTLEN:
 464     case EVP_PKEY_CTRL_GET_RSA_PSS_SALTLEN:
 465         if (rctx->pad_mode != RSA_PKCS1_PSS_PADDING) {
 466             ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_PSS_SALTLEN);
 467             return -2;
 468         }
 469         if (type == EVP_PKEY_CTRL_GET_RSA_PSS_SALTLEN) {
 470             *(int *)p2 = rctx->saltlen;
 471         } else {
 472             if (p1 < RSA_PSS_SALTLEN_MAX)
 473                 return -2;
 474             if (rsa_pss_restricted(rctx)) {
 475                 if (p1 == RSA_PSS_SALTLEN_AUTO
 476                     && ctx->operation == EVP_PKEY_OP_VERIFY) {
 477                     ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_PSS_SALTLEN);
 478                     return -2;
 479                 }
 480                 if ((p1 == RSA_PSS_SALTLEN_DIGEST
 481                      && rctx->min_saltlen > EVP_MD_get_size(rctx->md))
 482                     || (p1 >= 0 && p1 < rctx->min_saltlen)) {
 483                     ERR_raise(ERR_LIB_RSA, RSA_R_PSS_SALTLEN_TOO_SMALL);
 484                     return 0;
 485                 }
 486             }
 487             rctx->saltlen = p1;
 488         }
 489         return 1;
 490
 491     case EVP_PKEY_CTRL_RSA_KEYGEN_BITS:
 492         if (p1 < RSA_MIN_MODULUS_BITS) {
 493             ERR_raise(ERR_LIB_RSA, RSA_R_KEY_SIZE_TOO_SMALL);
 494             return -2;
 495         }
 496         rctx->nbits = p1;
 497         return 1;
 498
 499     case EVP_PKEY_CTRL_RSA_KEYGEN_PUBEXP:
 500         if (p2 == NULL || !BN_is_odd((BIGNUM *)p2) || BN_is_one((BIGNUM *)p2)) {
 501             ERR_raise(ERR_LIB_RSA, RSA_R_BAD_E_VALUE);
 502             return -2;
 503         }
 504         BN_free(rctx->pub_exp);
 505         rctx->pub_exp = p2;
 506         return 1;
 507
 508     case EVP_PKEY_CTRL_RSA_KEYGEN_PRIMES:
 509         if (p1 < RSA_DEFAULT_PRIME_NUM || p1 > RSA_MAX_PRIME_NUM) {
 510             ERR_raise(ERR_LIB_RSA, RSA_R_KEY_PRIME_NUM_INVALID);
 511             return -2;
 512         }
 513         rctx->primes = p1;
 514         return 1;
 515
 516     case EVP_PKEY_CTRL_RSA_OAEP_MD:
 517     case EVP_PKEY_CTRL_GET_RSA_OAEP_MD:
 518         if (rctx->pad_mode != RSA_PKCS1_OAEP_PADDING) {
 519             ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_PADDING_MODE);
 520             return -2;
 521         }
 522         if (type == EVP_PKEY_CTRL_GET_RSA_OAEP_MD)
 523             *(const EVP_MD **)p2 = rctx->md;
 524         else
 525             rctx->md = p2;
 526         return 1;
 527
 528     case EVP_PKEY_CTRL_MD:
 529         if (!check_padding_md(p2, rctx->pad_mode))
 530             return 0;
 531         if (rsa_pss_restricted(rctx)) {
 532             if (EVP_MD_get_type(rctx->md) == EVP_MD_get_type(p2))
 533                 return 1;
 534             ERR_raise(ERR_LIB_RSA, RSA_R_DIGEST_NOT_ALLOWED);
 535             return 0;
 536         }
 537         rctx->md = p2;
 538         return 1;
 539
 540     case EVP_PKEY_CTRL_GET_MD:
 541         *(const EVP_MD **)p2 = rctx->md;
 542         return 1;
 543
 544     case EVP_PKEY_CTRL_RSA_MGF1_MD:
 545     case EVP_PKEY_CTRL_GET_RSA_MGF1_MD:
 546         if (rctx->pad_mode != RSA_PKCS1_PSS_PADDING
 547             && rctx->pad_mode != RSA_PKCS1_OAEP_PADDING) {
 548             ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_MGF1_MD);
 549             return -2;
 550         }
 551         if (type == EVP_PKEY_CTRL_GET_RSA_MGF1_MD) {
 552             if (rctx->mgf1md)
 553                 *(const EVP_MD **)p2 = rctx->mgf1md;
 554             else
 555                 *(const EVP_MD **)p2 = rctx->md;
 556         } else {
 557             if (rsa_pss_restricted(rctx)) {
 558                 if (EVP_MD_get_type(rctx->mgf1md) == EVP_MD_get_type(p2))
 559                     return 1;
 560                 ERR_raise(ERR_LIB_RSA, RSA_R_MGF1_DIGEST_NOT_ALLOWED);
 561                 return 0;
 562             }
 563             rctx->mgf1md = p2;
 564         }
 565         return 1;
 566
 567     case EVP_PKEY_CTRL_RSA_OAEP_LABEL:
 568         if (rctx->pad_mode != RSA_PKCS1_OAEP_PADDING) {
 569             ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_PADDING_MODE);
 570             return -2;
 571         }
 572         OPENSSL_free(rctx->oaep_label);
 573         if (p2 && p1 > 0) {
 574             rctx->oaep_label = p2;
 575             rctx->oaep_labellen = p1;
 576         } else {
 577             rctx->oaep_label = NULL;
 578             rctx->oaep_labellen = 0;
 579         }
 580         return 1;
 581
 582     case EVP_PKEY_CTRL_GET_RSA_OAEP_LABEL:
 583         if (rctx->pad_mode != RSA_PKCS1_OAEP_PADDING) {
 584             ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_PADDING_MODE);
 585             return -2;
 586         }
 587         *(unsigned char **)p2 = rctx->oaep_label;
 588         return rctx->oaep_labellen;
 589
 590     case EVP_PKEY_CTRL_DIGESTINIT:
 591     case EVP_PKEY_CTRL_PKCS7_SIGN:
 592 #ifndef OPENSSL_NO_CMS
 593     case EVP_PKEY_CTRL_CMS_SIGN:
 594 #endif
 595     return 1;
 596
 597     case EVP_PKEY_CTRL_PKCS7_ENCRYPT:
 598     case EVP_PKEY_CTRL_PKCS7_DECRYPT:
 599 #ifndef OPENSSL_NO_CMS
 600     case EVP_PKEY_CTRL_CMS_DECRYPT:
 601     case EVP_PKEY_CTRL_CMS_ENCRYPT:
 602 #endif
 603     if (!pkey_ctx_is_pss(ctx))
 604         return 1;
 605     /* fall through */
 606     case EVP_PKEY_CTRL_PEER_KEY:
 607         ERR_raise(ERR_LIB_RSA, RSA_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
 608         return -2;
 609
 610     default:
 611         return -2;
 612
 613     }
 614 }
 615
 616 static int pkey_rsa_ctrl_str(EVP_PKEY_CTX *ctx,
 617                              const char *type, const char *value)
 618 {
 619     if (value == NULL) {
 620         ERR_raise(ERR_LIB_RSA, RSA_R_VALUE_MISSING);
 621         return 0;
 622     }
 623     if (strcmp(type, "rsa_padding_mode") == 0) {
 624         int pm;
 625
 626         if (strcmp(value, "pkcs1") == 0) {
 627             pm = RSA_PKCS1_PADDING;
 628         } else if (strcmp(value, "none") == 0) {
 629             pm = RSA_NO_PADDING;
 630         } else if (strcmp(value, "oeap") == 0) {
 631             pm = RSA_PKCS1_OAEP_PADDING;
 632         } else if (strcmp(value, "oaep") == 0) {
 633             pm = RSA_PKCS1_OAEP_PADDING;
 634         } else if (strcmp(value, "x931") == 0) {
 635             pm = RSA_X931_PADDING;
 636         } else if (strcmp(value, "pss") == 0) {
 637             pm = RSA_PKCS1_PSS_PADDING;
 638         } else {
 639             ERR_raise(ERR_LIB_RSA, RSA_R_UNKNOWN_PADDING_TYPE);
 640             return -2;
 641         }
 642         return EVP_PKEY_CTX_set_rsa_padding(ctx, pm);
 643     }
 644
 645     if (strcmp(type, "rsa_pss_saltlen") == 0) {
 646         int saltlen;
 647
 648         if (!strcmp(value, "digest"))
 649             saltlen = RSA_PSS_SALTLEN_DIGEST;
 650         else if (!strcmp(value, "max"))
 651             saltlen = RSA_PSS_SALTLEN_MAX;
 652         else if (!strcmp(value, "auto"))
 653             saltlen = RSA_PSS_SALTLEN_AUTO;
 654         else
 655             saltlen = atoi(value);
 656         return EVP_PKEY_CTX_set_rsa_pss_saltlen(ctx, saltlen);
 657     }
 658
 659     if (strcmp(type, "rsa_keygen_bits") == 0) {
 660         int nbits = atoi(value);
 661
 662         return EVP_PKEY_CTX_set_rsa_keygen_bits(ctx, nbits);
 663     }
 664
 665     if (strcmp(type, "rsa_keygen_pubexp") == 0) {
 666         int ret;
 667
 668         BIGNUM *pubexp = NULL;
 669         if (!BN_asc2bn(&pubexp, value))
 670             return 0;
 671         ret = EVP_PKEY_CTX_set1_rsa_keygen_pubexp(ctx, pubexp);
 672         BN_free(pubexp);
 673         return ret;
 674     }
 675
 676     if (strcmp(type, "rsa_keygen_primes") == 0) {
 677         int nprimes = atoi(value);
 678
 679         return EVP_PKEY_CTX_set_rsa_keygen_primes(ctx, nprimes);
 680     }
 681
 682     if (strcmp(type, "rsa_mgf1_md") == 0)
 683         return EVP_PKEY_CTX_md(ctx,
 684                                EVP_PKEY_OP_TYPE_SIG | EVP_PKEY_OP_TYPE_CRYPT,
 685                                EVP_PKEY_CTRL_RSA_MGF1_MD, value);
 686
 687     if (pkey_ctx_is_pss(ctx)) {
 688
 689         if (strcmp(type, "rsa_pss_keygen_mgf1_md") == 0)
 690             return EVP_PKEY_CTX_md(ctx, EVP_PKEY_OP_KEYGEN,
 691                                    EVP_PKEY_CTRL_RSA_MGF1_MD, value);
 692
 693         if (strcmp(type, "rsa_pss_keygen_md") == 0)
 694             return EVP_PKEY_CTX_md(ctx, EVP_PKEY_OP_KEYGEN,
 695                                    EVP_PKEY_CTRL_MD, value);
 696
 697         if (strcmp(type, "rsa_pss_keygen_saltlen") == 0) {
 698             int saltlen = atoi(value);
 699
 700             return EVP_PKEY_CTX_set_rsa_pss_keygen_saltlen(ctx, saltlen);
 701         }
 702     }
 703
 704     if (strcmp(type, "rsa_oaep_md") == 0)
 705         return EVP_PKEY_CTX_md(ctx, EVP_PKEY_OP_TYPE_CRYPT,
 706                                EVP_PKEY_CTRL_RSA_OAEP_MD, value);
 707
 708     if (strcmp(type, "rsa_oaep_label") == 0) {
 709         unsigned char *lab;
 710         long lablen;
 711         int ret;
 712
 713         lab = OPENSSL_hexstr2buf(value, &lablen);
 714         if (!lab)
 715             return 0;
 716         ret = EVP_PKEY_CTX_set0_rsa_oaep_label(ctx, lab, lablen);
 717         if (ret <= 0)
 718             OPENSSL_free(lab);
 719         return ret;
 720     }
 721
 722     return -2;
 723 }
 724
 725 /* Set PSS parameters when generating a key, if necessary */
 726 static int rsa_set_pss_param(RSA *rsa, EVP_PKEY_CTX *ctx)
 727 {
 728     RSA_PKEY_CTX *rctx = ctx->data;
 729
 730     if (!pkey_ctx_is_pss(ctx))
 731         return 1;
 732     /* If all parameters are default values don't set pss */
 733     if (rctx->md == NULL && rctx->mgf1md == NULL && rctx->saltlen == -2)
 734         return 1;
 735     rsa->pss = ossl_rsa_pss_params_create(rctx->md, rctx->mgf1md,
 736                                           rctx->saltlen == -2
 737                                           ? 0 : rctx->saltlen);
 738     if (rsa->pss == NULL)
 739         return 0;
 740     return 1;
 741 }
 742
 743 static int pkey_rsa_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
 744 {
 745     RSA *rsa = NULL;
 746     RSA_PKEY_CTX *rctx = ctx->data;
 747     BN_GENCB *pcb;
 748     int ret;
 749
 750     if (rctx->pub_exp == NULL) {
 751         rctx->pub_exp = BN_new();
 752         if (rctx->pub_exp == NULL || !BN_set_word(rctx->pub_exp, RSA_F4))
 753             return 0;
 754     }
 755     rsa = RSA_new();
 756     if (rsa == NULL)
 757         return 0;
 758     if (ctx->pkey_gencb) {
 759         pcb = BN_GENCB_new();
 760         if (pcb == NULL) {
 761             RSA_free(rsa);
 762             return 0;
 763         }
 764         evp_pkey_set_cb_translate(pcb, ctx);
 765     } else {
 766         pcb = NULL;
 767     }
 768     ret = RSA_generate_multi_prime_key(rsa, rctx->nbits, rctx->primes,
 769                                        rctx->pub_exp, pcb);
 770     BN_GENCB_free(pcb);
 771     if (ret > 0 && !rsa_set_pss_param(rsa, ctx)) {
 772         RSA_free(rsa);
 773         return 0;
 774     }
 775     if (ret > 0)
 776         EVP_PKEY_assign(pkey, ctx->pmeth->pkey_id, rsa);
 777     else
 778         RSA_free(rsa);
 779     return ret;
 780 }
 781
 782 static const EVP_PKEY_METHOD rsa_pkey_meth = {
 783     EVP_PKEY_RSA,
 784     EVP_PKEY_FLAG_AUTOARGLEN,
 785     pkey_rsa_init,
 786     pkey_rsa_copy,
 787     pkey_rsa_cleanup,
 788
 789     0, 0,
 790
 791     0,
 792     pkey_rsa_keygen,
 793
 794     0,
 795     pkey_rsa_sign,
 796
 797     0,
 798     pkey_rsa_verify,
 799
 800     0,
 801     pkey_rsa_verifyrecover,
 802
 803     0, 0, 0, 0,
 804
 805     0,
 806     pkey_rsa_encrypt,
 807
 808     0,
 809     pkey_rsa_decrypt,
 810
 811     0, 0,
 812
 813     pkey_rsa_ctrl,
 814     pkey_rsa_ctrl_str
 815 };
 816
 817 const EVP_PKEY_METHOD *ossl_rsa_pkey_method(void)
 818 {
 819     return &rsa_pkey_meth;
 820 }
 821
 822 /*
 823  * Called for PSS sign or verify initialisation: checks PSS parameter
 824  * sanity and sets any restrictions on key usage.
 825  */
 826
 827 static int pkey_pss_init(EVP_PKEY_CTX *ctx)
 828 {
 829     const RSA *rsa;
 830     RSA_PKEY_CTX *rctx = ctx->data;
 831     const EVP_MD *md;
 832     const EVP_MD *mgf1md;
 833     int min_saltlen, max_saltlen;
 834
 835     /* Should never happen */
 836     if (!pkey_ctx_is_pss(ctx))
 837         return 0;
 838     rsa = EVP_PKEY_get0_RSA(ctx->pkey);
 839     /* If no restrictions just return */
 840     if (rsa->pss == NULL)
 841         return 1;
 842     /* Get and check parameters */
 843     if (!ossl_rsa_pss_get_param(rsa->pss, &md, &mgf1md, &min_saltlen))
 844         return 0;
 845
 846     /* See if minimum salt length exceeds maximum possible */
 847     max_saltlen = RSA_size(rsa) - EVP_MD_get_size(md);
 848     if ((RSA_bits(rsa) & 0x7) == 1)
 849         max_saltlen--;
 850     if (min_saltlen > max_saltlen) {
 851         ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_SALT_LENGTH);
 852         return 0;
 853     }
 854
 855     rctx->min_saltlen = min_saltlen;
 856
 857     /*
 858      * Set PSS restrictions as defaults: we can then block any attempt to
 859      * use invalid values in pkey_rsa_ctrl
 860      */
 861
 862     rctx->md = md;
 863     rctx->mgf1md = mgf1md;
 864     rctx->saltlen = min_saltlen;
 865
 866     return 1;
 867 }
 868
 869 static const EVP_PKEY_METHOD rsa_pss_pkey_meth = {
 870     EVP_PKEY_RSA_PSS,
 871     EVP_PKEY_FLAG_AUTOARGLEN,
 872     pkey_rsa_init,
 873     pkey_rsa_copy,
 874     pkey_rsa_cleanup,
 875
 876     0, 0,
 877
 878     0,
 879     pkey_rsa_keygen,
 880
 881     pkey_pss_init,
 882     pkey_rsa_sign,
 883
 884     pkey_pss_init,
 885     pkey_rsa_verify,
 886
 887     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 888
 889     pkey_rsa_ctrl,
 890     pkey_rsa_ctrl_str
 891 };
 892
 893 const EVP_PKEY_METHOD *ossl_rsa_pss_pkey_method(void)
 894 {
 895     return &rsa_pss_pkey_meth;
 896 }