text: /*
   * Copyright 2006-2021 The OpenSSL Project Authors. All Rights Reserved.
   *
   * Licensed under the Apache License 2.0 (the "License").  You may not use
   * this file except in compliance with the License.  You can obtain a copy
   * in the file LICENSE in the source distribution or at
   * https://www.openssl.org/source/license.html
   */
  
  /*
   * RSA low level APIs are deprecated for public use, but still ok for
   * internal use.
   */
  #include "internal/deprecated.h"
  
  #include "internal/constant_time.h"
  
  #include <stdio.h>
  #include "internal/cryptlib.h"
  #include <openssl/asn1t.h>
  #include <openssl/x509.h>
  #include <openssl/rsa.h>
  #include <openssl/bn.h>
  #include <openssl/evp.h>
  #include <openssl/x509v3.h>
  #include <openssl/cms.h>
  #include "crypto/evp.h"
  #include "crypto/rsa.h"
  #include "rsa_local.h"
  
  /* RSA pkey context structure */
  
  typedef struct {
      /* Key gen parameters */
      int nbits;
      BIGNUM *pub_exp;
      int primes;
      /* Keygen callback info */
      int gentmp[2];
      /* RSA padding mode */
      int pad_mode;
      /* message digest */
      const EVP_MD *md;
      /* message digest for MGF1 */
      const EVP_MD *mgf1md;
      /* PSS salt length */
      int saltlen;
      /* Minimum salt length or -1 if no PSS parameter restriction */
      int min_saltlen;
      /* Temp buffer */
      unsigned char *tbuf;
      /* OAEP label */
      unsigned char *oaep_label;
      size_t oaep_labellen;
  } RSA_PKEY_CTX;
  
  /* True if PSS parameters are restricted */
  #define rsa_pss_restricted(rctx) (rctx->min_saltlen != -1)
  
  static int pkey_rsa_init(EVP_PKEY_CTX *ctx)
  {
      RSA_PKEY_CTX *rctx = OPENSSL_zalloc(sizeof(*rctx));
  
      if (rctx == NULL)
          return 0;
      rctx->nbits = 2048;
      rctx->primes = RSA_DEFAULT_PRIME_NUM;
      if (pkey_ctx_is_pss(ctx))
          rctx->pad_mode = RSA_PKCS1_PSS_PADDING;
      else
          rctx->pad_mode = RSA_PKCS1_PADDING;
      /* Maximum for sign, auto for verify */
      rctx->saltlen = RSA_PSS_SALTLEN_AUTO;
      rctx->min_saltlen = -1;
      ctx->data = rctx;
      ctx->keygen_info = rctx->gentmp;
      ctx->keygen_info_count = 2;
  
      return 1;
  }
  
  static int pkey_rsa_copy(EVP_PKEY_CTX *dst, const EVP_PKEY_CTX *src)
  {
      RSA_PKEY_CTX *dctx, *sctx;
  
      if (!pkey_rsa_init(dst))
          return 0;
      sctx = src->data;
      dctx = dst->data;
      dctx->nbits = sctx->nbits;
      if (sctx->pub_exp) {
          dctx->pub_exp = BN_dup(sctx->pub_exp);
          if (!dctx->pub_exp)
              return 0;
      }
      dctx->pad_mode = sctx->pad_mode;
      dctx->md = sctx->md;
      dctx->mgf1md = sctx->mgf1md;
      dctx->saltlen = sctx->saltlen;
      if (sctx->oaep_label) {
          OPENSSL_free(dctx->oaep_label);
          dctx->oaep_label = OPENSSL_memdup(sctx->oaep_label, sctx->oaep_labellen);
          if (!dctx->oaep_label)
              return 0;
          dctx->oaep_labellen = sctx->oaep_labellen;
      }
      return 1;
  }
  
  static int setup_tbuf(RSA_PKEY_CTX *ctx, EVP_PKEY_CTX *pk)
  {
      if (ctx->tbuf != NULL)
          return 1;
      if ((ctx->tbuf =
              OPENSSL_malloc(RSA_size(EVP_PKEY_get0_RSA(pk->pkey)))) == NULL) {
          ERR_raise(ERR_LIB_RSA, ERR_R_MALLOC_FAILURE);
          return 0;
      }
      return 1;
  }
  
  static void pkey_rsa_cleanup(EVP_PKEY_CTX *ctx)
  {
      RSA_PKEY_CTX *rctx = ctx->data;
      if (rctx) {
          BN_free(rctx->pub_exp);
          OPENSSL_free(rctx->tbuf);
          OPENSSL_free(rctx->oaep_label);
          OPENSSL_free(rctx);
      }
  }
  
  static int pkey_rsa_sign(EVP_PKEY_CTX *ctx, unsigned char *sig,
                           size_t *siglen, const unsigned char *tbs,
                           size_t tbslen)
  {
      int ret;
      RSA_PKEY_CTX *rctx = ctx->data;
      /*
       * Discard const. Its marked as const because this may be a cached copy of
       * the "real" key. These calls don't make any modifications that need to
       * be reflected back in the "original" key.
       */
      RSA *rsa = (RSA *)EVP_PKEY_get0_RSA(ctx->pkey);
  
      if (rctx->md) {
          if (tbslen != (size_t)EVP_MD_get_size(rctx->md)) {
              ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_DIGEST_LENGTH);
              return -1;
          }
  
          if (EVP_MD_get_type(rctx->md) == NID_mdc2) {
              unsigned int sltmp;
              if (rctx->pad_mode != RSA_PKCS1_PADDING)
                  return -1;
              ret = RSA_sign_ASN1_OCTET_STRING(0, tbs, tbslen, sig, &sltmp, rsa);
  
              if (ret <= 0)
                  return ret;
              ret = sltmp;
          } else if (rctx->pad_mode == RSA_X931_PADDING) {
              if ((size_t)RSA_size(rsa) < tbslen + 1) {
                  ERR_raise(ERR_LIB_RSA, RSA_R_KEY_SIZE_TOO_SMALL);
                  return -1;
              }
              if (!setup_tbuf(rctx, ctx)) {
                  ERR_raise(ERR_LIB_RSA, ERR_R_MALLOC_FAILURE);
                  return -1;
              }
              memcpy(rctx->tbuf, tbs, tbslen);
              rctx->tbuf[tbslen] = RSA_X931_hash_id(EVP_MD_get_type(rctx->md));
              ret = RSA_private_encrypt(tbslen + 1, rctx->tbuf,
                                        sig, rsa, RSA_X931_PADDING);
          } else if (rctx->pad_mode == RSA_PKCS1_PADDING) {
              unsigned int sltmp;
              ret = RSA_sign(EVP_MD_get_type(rctx->md),
                             tbs, tbslen, sig, &sltmp, rsa);
              if (ret <= 0)
                  return ret;
              ret = sltmp;
          } else if (rctx->pad_mode == RSA_PKCS1_PSS_PADDING) {
              if (!setup_tbuf(rctx, ctx))
                  return -1;
              if (!RSA_padding_add_PKCS1_PSS_mgf1(rsa,
                                                  rctx->tbuf, tbs,
                                                  rctx->md, rctx->mgf1md,
                                                  rctx->saltlen))
                  return -1;
              ret = RSA_private_encrypt(RSA_size(rsa), rctx->tbuf,
                                        sig, rsa, RSA_NO_PADDING);
          } else {
              return -1;
          }
      } else {
          ret = RSA_private_encrypt(tbslen, tbs, sig, rsa, rctx->pad_mode);
      }
      if (ret < 0)
          return ret;
      *siglen = ret;
      return 1;
  }
  
  static int pkey_rsa_verifyrecover(EVP_PKEY_CTX *ctx,
                                    unsigned char *rout, size_t *routlen,
                                    const unsigned char *sig, size_t siglen)
  {
      int ret;
      RSA_PKEY_CTX *rctx = ctx->data;
      /*
       * Discard const. Its marked as const because this may be a cached copy of
       * the "real" key. These calls don't make any modifications that need to
       * be reflected back in the "original" key.
       */
      RSA *rsa = (RSA *)EVP_PKEY_get0_RSA(ctx->pkey);
  
      if (rctx->md) {
          if (rctx->pad_mode == RSA_X931_PADDING) {
              if (!setup_tbuf(rctx, ctx))
                  return -1;
              ret = RSA_public_decrypt(siglen, sig, rctx->tbuf, rsa,
                                       RSA_X931_PADDING);
              if (ret < 1)
                  return 0;
              ret--;
              if (rctx->tbuf[ret] != RSA_X931_hash_id(EVP_MD_get_type(rctx->md))) {
                  ERR_raise(ERR_LIB_RSA, RSA_R_ALGORITHM_MISMATCH);
                  return 0;
              }
              if (ret != EVP_MD_get_size(rctx->md)) {
                  ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_DIGEST_LENGTH);
                  return 0;
              }
              if (rout)
                  memcpy(rout, rctx->tbuf, ret);
          } else if (rctx->pad_mode == RSA_PKCS1_PADDING) {
              size_t sltmp;
              ret = ossl_rsa_verify(EVP_MD_get_type(rctx->md),
                                    NULL, 0, rout, &sltmp,
                                    sig, siglen, rsa);
              if (ret <= 0)
                  return 0;
              ret = sltmp;
          } else {
              return -1;
          }
      } else {
          ret = RSA_public_decrypt(siglen, sig, rout, rsa, rctx->pad_mode);
      }
      if (ret < 0)
          return ret;
      *routlen = ret;
      return 1;
  }
  
  static int pkey_rsa_verify(EVP_PKEY_CTX *ctx,
                             const unsigned char *sig, size_t siglen,
                             const unsigned char *tbs, size_t tbslen)
  {
      RSA_PKEY_CTX *rctx = ctx->data;
      /*
       * Discard const. Its marked as const because this may be a cached copy of
       * the "real" key. These calls don't make any modifications that need to
       * be reflected back in the "original" key.
       */
      RSA *rsa = (RSA *)EVP_PKEY_get0_RSA(ctx->pkey);
      size_t rslen;
  
      if (rctx->md) {
          if (rctx->pad_mode == RSA_PKCS1_PADDING)
              return RSA_verify(EVP_MD_get_type(rctx->md), tbs, tbslen,
                                sig, siglen, rsa);
          if (tbslen != (size_t)EVP_MD_get_size(rctx->md)) {
              ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_DIGEST_LENGTH);
              return -1;
          }
          if (rctx->pad_mode == RSA_X931_PADDING) {
              if (pkey_rsa_verifyrecover(ctx, NULL, &rslen, sig, siglen) <= 0)
                  return 0;
          } else if (rctx->pad_mode == RSA_PKCS1_PSS_PADDING) {
              int ret;
              if (!setup_tbuf(rctx, ctx))
                  return -1;
              ret = RSA_public_decrypt(siglen, sig, rctx->tbuf,
                                       rsa, RSA_NO_PADDING);
              if (ret <= 0)
                  return 0;
              ret = RSA_verify_PKCS1_PSS_mgf1(rsa, tbs,
                                              rctx->md, rctx->mgf1md,
                                              rctx->tbuf, rctx->saltlen);
              if (ret <= 0)
                  return 0;
              return 1;
          } else {
              return -1;
          }
      } else {
          if (!setup_tbuf(rctx, ctx))
              return -1;
          rslen = RSA_public_decrypt(siglen, sig, rctx->tbuf,
                                     rsa, rctx->pad_mode);
          if (rslen == 0)
              return 0;
      }
  
      if ((rslen != tbslen) || memcmp(tbs, rctx->tbuf, rslen))
          return 0;
  
      return 1;
  
  }
  
  static int pkey_rsa_encrypt(EVP_PKEY_CTX *ctx,
                              unsigned char *out, size_t *outlen,
                              const unsigned char *in, size_t inlen)
  {
      int ret;
      RSA_PKEY_CTX *rctx = ctx->data;
      /*
       * Discard const. Its marked as const because this may be a cached copy of
       * the "real" key. These calls don't make any modifications that need to
       * be reflected back in the "original" key.
       */
      RSA *rsa = (RSA *)EVP_PKEY_get0_RSA(ctx->pkey);
  
      if (rctx->pad_mode == RSA_PKCS1_OAEP_PADDING) {
          int klen = RSA_size(rsa);
          if (!setup_tbuf(rctx, ctx))
              return -1;
          if (!RSA_padding_add_PKCS1_OAEP_mgf1(rctx->tbuf, klen,
                                               in, inlen,
                                               rctx->oaep_label,
                                               rctx->oaep_labellen,
                                               rctx->md, rctx->mgf1md))
              return -1;
          ret = RSA_public_encrypt(klen, rctx->tbuf, out, rsa, RSA_NO_PADDING);
      } else {
          ret = RSA_public_encrypt(inlen, in, out, rsa, rctx->pad_mode);
      }
      if (ret < 0)
          return ret;
      *outlen = ret;
      return 1;
  }
  
  static int pkey_rsa_decrypt(EVP_PKEY_CTX *ctx,
                              unsigned char *out, size_t *outlen,
                              const unsigned char *in, size_t inlen)
  {
      int ret;
      RSA_PKEY_CTX *rctx = ctx->data;
      /*
       * Discard const. Its marked as const because this may be a cached copy of
       * the "real" key. These calls don't make any modifications that need to
       * be reflected back in the "original" key.
       */
      RSA *rsa = (RSA *)EVP_PKEY_get0_RSA(ctx->pkey);
  
      if (rctx->pad_mode == RSA_PKCS1_OAEP_PADDING) {
          if (!setup_tbuf(rctx, ctx))
              return -1;
          ret = RSA_private_decrypt(inlen, in, rctx->tbuf, rsa, RSA_NO_PADDING);
          if (ret <= 0)
              return ret;
          ret = RSA_padding_check_PKCS1_OAEP_mgf1(out, ret, rctx->tbuf,
                                                  ret, ret,
                                                  rctx->oaep_label,
                                                  rctx->oaep_labellen,
                                                  rctx->md, rctx->mgf1md);
      } else {
          ret = RSA_private_decrypt(inlen, in, out, rsa, rctx->pad_mode);
      }
      *outlen = constant_time_select_s(constant_time_msb_s(ret), *outlen, ret);
      ret = constant_time_select_int(constant_time_msb(ret), ret, 1);
      return ret;
  }
  
  static int check_padding_md(const EVP_MD *md, int padding)
  {
      int mdnid;
  
      if (!md)
          return 1;
  
      mdnid = EVP_MD_get_type(md);
  
      if (padding == RSA_NO_PADDING) {
          ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_PADDING_MODE);
          return 0;
      }
  
      if (padding == RSA_X931_PADDING) {
          if (RSA_X931_hash_id(mdnid) == -1) {
              ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_X931_DIGEST);
              return 0;
          }
      } else {
          switch(mdnid) {
          /* List of all supported RSA digests */
          case NID_sha1:
          case NID_sha224:
          case NID_sha256:
          case NID_sha384:
          case NID_sha512:
          case NID_sha512_224:
          case NID_sha512_256:
          case NID_md5:
          case NID_md5_sha1:
          case NID_md2:
          case NID_md4:
          case NID_mdc2:
          case NID_ripemd160:
          case NID_sha3_224:
          case NID_sha3_256:
          case NID_sha3_384:
          case NID_sha3_512:
              return 1;
  
          default:
              ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_DIGEST);
              return 0;
  
          }
      }
  
      return 1;
  }
  
  static int pkey_rsa_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
  {
      RSA_PKEY_CTX *rctx = ctx->data;
  
      switch (type) {
      case EVP_PKEY_CTRL_RSA_PADDING:
          if ((p1 >= RSA_PKCS1_PADDING) && (p1 <= RSA_PKCS1_PSS_PADDING)) {
              if (!check_padding_md(rctx->md, p1))
                  return 0;
              if (p1 == RSA_PKCS1_PSS_PADDING) {
                  if (!(ctx->operation &
                        (EVP_PKEY_OP_SIGN | EVP_PKEY_OP_VERIFY)))
                      goto bad_pad;
                  if (!rctx->md)
                      rctx->md = EVP_sha1();
              } else if (pkey_ctx_is_pss(ctx)) {
                  goto bad_pad;
              }
              if (p1 == RSA_PKCS1_OAEP_PADDING) {
                  if (!(ctx->operation & EVP_PKEY_OP_TYPE_CRYPT))
                      goto bad_pad;
                  if (!rctx->md)
                      rctx->md = EVP_sha1();
              }
              rctx->pad_mode = p1;
              return 1;
          }
   bad_pad:
          ERR_raise(ERR_LIB_RSA, RSA_R_ILLEGAL_OR_UNSUPPORTED_PADDING_MODE);
          return -2;
  
      case EVP_PKEY_CTRL_GET_RSA_PADDING:
          *(int *)p2 = rctx->pad_mode;
          return 1;
  
      case EVP_PKEY_CTRL_RSA_PSS_SALTLEN:
      case EVP_PKEY_CTRL_GET_RSA_PSS_SALTLEN:
          if (rctx->pad_mode != RSA_PKCS1_PSS_PADDING) {
              ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_PSS_SALTLEN);
              return -2;
          }
          if (type == EVP_PKEY_CTRL_GET_RSA_PSS_SALTLEN) {
              *(int *)p2 = rctx->saltlen;
          } else {
              if (p1 < RSA_PSS_SALTLEN_MAX)
                  return -2;
              if (rsa_pss_restricted(rctx)) {
                  if (p1 == RSA_PSS_SALTLEN_AUTO
                      && ctx->operation == EVP_PKEY_OP_VERIFY) {
                      ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_PSS_SALTLEN);
                      return -2;
                  }
                  if ((p1 == RSA_PSS_SALTLEN_DIGEST
                       && rctx->min_saltlen > EVP_MD_get_size(rctx->md))
                      || (p1 >= 0 && p1 < rctx->min_saltlen)) {
                      ERR_raise(ERR_LIB_RSA, RSA_R_PSS_SALTLEN_TOO_SMALL);
                      return 0;
                  }
              }
              rctx->saltlen = p1;
          }
          return 1;
  
      case EVP_PKEY_CTRL_RSA_KEYGEN_BITS:
          if (p1 < RSA_MIN_MODULUS_BITS) {
              ERR_raise(ERR_LIB_RSA, RSA_R_KEY_SIZE_TOO_SMALL);
              return -2;
          }
          rctx->nbits = p1;
          return 1;
  
      case EVP_PKEY_CTRL_RSA_KEYGEN_PUBEXP:
          if (p2 == NULL || !BN_is_odd((BIGNUM *)p2) || BN_is_one((BIGNUM *)p2)) {
              ERR_raise(ERR_LIB_RSA, RSA_R_BAD_E_VALUE);
              return -2;
          }
          BN_free(rctx->pub_exp);
          rctx->pub_exp = p2;
          return 1;
  
      case EVP_PKEY_CTRL_RSA_KEYGEN_PRIMES:
          if (p1 < RSA_DEFAULT_PRIME_NUM || p1 > RSA_MAX_PRIME_NUM) {
              ERR_raise(ERR_LIB_RSA, RSA_R_KEY_PRIME_NUM_INVALID);
              return -2;
          }
          rctx->primes = p1;
          return 1;
  
      case EVP_PKEY_CTRL_RSA_OAEP_MD:
      case EVP_PKEY_CTRL_GET_RSA_OAEP_MD:
          if (rctx->pad_mode != RSA_PKCS1_OAEP_PADDING) {
              ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_PADDING_MODE);
              return -2;
          }
          if (type == EVP_PKEY_CTRL_GET_RSA_OAEP_MD)
              *(const EVP_MD **)p2 = rctx->md;
          else
              rctx->md = p2;
          return 1;
  
      case EVP_PKEY_CTRL_MD:
          if (!check_padding_md(p2, rctx->pad_mode))
              return 0;
          if (rsa_pss_restricted(rctx)) {
              if (EVP_MD_get_type(rctx->md) == EVP_MD_get_type(p2))
                  return 1;
              ERR_raise(ERR_LIB_RSA, RSA_R_DIGEST_NOT_ALLOWED);
              return 0;
          }
          rctx->md = p2;
          return 1;
  
      case EVP_PKEY_CTRL_GET_MD:
          *(const EVP_MD **)p2 = rctx->md;
          return 1;
  
      case EVP_PKEY_CTRL_RSA_MGF1_MD:
      case EVP_PKEY_CTRL_GET_RSA_MGF1_MD:
          if (rctx->pad_mode != RSA_PKCS1_PSS_PADDING
              && rctx->pad_mode != RSA_PKCS1_OAEP_PADDING) {
              ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_MGF1_MD);
              return -2;
          }
          if (type == EVP_PKEY_CTRL_GET_RSA_MGF1_MD) {
              if (rctx->mgf1md)
                  *(const EVP_MD **)p2 = rctx->mgf1md;
              else
                  *(const EVP_MD **)p2 = rctx->md;
          } else {
              if (rsa_pss_restricted(rctx)) {
                  if (EVP_MD_get_type(rctx->mgf1md) == EVP_MD_get_type(p2))
                      return 1;
                  ERR_raise(ERR_LIB_RSA, RSA_R_MGF1_DIGEST_NOT_ALLOWED);
                  return 0;
              }
              rctx->mgf1md = p2;
          }
          return 1;
  
      case EVP_PKEY_CTRL_RSA_OAEP_LABEL:
          if (rctx->pad_mode != RSA_PKCS1_OAEP_PADDING) {
              ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_PADDING_MODE);
              return -2;
          }
          OPENSSL_free(rctx->oaep_label);
          if (p2 && p1 > 0) {
              rctx->oaep_label = p2;
              rctx->oaep_labellen = p1;
          } else {
              rctx->oaep_label = NULL;
              rctx->oaep_labellen = 0;
          }
          return 1;
  
      case EVP_PKEY_CTRL_GET_RSA_OAEP_LABEL:
          if (rctx->pad_mode != RSA_PKCS1_OAEP_PADDING) {
              ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_PADDING_MODE);
              return -2;
          }
          *(unsigned char **)p2 = rctx->oaep_label;
          return rctx->oaep_labellen;
  
      case EVP_PKEY_CTRL_DIGESTINIT:
      case EVP_PKEY_CTRL_PKCS7_SIGN:
  #ifndef OPENSSL_NO_CMS
      case EVP_PKEY_CTRL_CMS_SIGN:
  #endif
      return 1;
  
      case EVP_PKEY_CTRL_PKCS7_ENCRYPT:
      case EVP_PKEY_CTRL_PKCS7_DECRYPT:
  #ifndef OPENSSL_NO_CMS
      case EVP_PKEY_CTRL_CMS_DECRYPT:
      case EVP_PKEY_CTRL_CMS_ENCRYPT:
  #endif
      if (!pkey_ctx_is_pss(ctx))
          return 1;
      /* fall through */
      case EVP_PKEY_CTRL_PEER_KEY:
          ERR_raise(ERR_LIB_RSA, RSA_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
          return -2;
  
      default:
          return -2;
  
      }
  }
  
  static int pkey_rsa_ctrl_str(EVP_PKEY_CTX *ctx,
                               const char *type, const char *value)
  {
      if (value == NULL) {
          ERR_raise(ERR_LIB_RSA, RSA_R_VALUE_MISSING);
          return 0;
      }
      if (strcmp(type, "rsa_padding_mode") == 0) {
          int pm;
  
          if (strcmp(value, "pkcs1") == 0) {
              pm = RSA_PKCS1_PADDING;
          } else if (strcmp(value, "none") == 0) {
              pm = RSA_NO_PADDING;
          } else if (strcmp(value, "oeap") == 0) {
              pm = RSA_PKCS1_OAEP_PADDING;
          } else if (strcmp(value, "oaep") == 0) {
              pm = RSA_PKCS1_OAEP_PADDING;
          } else if (strcmp(value, "x931") == 0) {
              pm = RSA_X931_PADDING;
          } else if (strcmp(value, "pss") == 0) {
              pm = RSA_PKCS1_PSS_PADDING;
          } else {
              ERR_raise(ERR_LIB_RSA, RSA_R_UNKNOWN_PADDING_TYPE);
              return -2;
          }
          return EVP_PKEY_CTX_set_rsa_padding(ctx, pm);
      }
  
      if (strcmp(type, "rsa_pss_saltlen") == 0) {
          int saltlen;
  
          if (!strcmp(value, "digest"))
              saltlen = RSA_PSS_SALTLEN_DIGEST;
          else if (!strcmp(value, "max"))
              saltlen = RSA_PSS_SALTLEN_MAX;
          else if (!strcmp(value, "auto"))
              saltlen = RSA_PSS_SALTLEN_AUTO;
          else
              saltlen = atoi(value);
          return EVP_PKEY_CTX_set_rsa_pss_saltlen(ctx, saltlen);
      }
  
      if (strcmp(type, "rsa_keygen_bits") == 0) {
          int nbits = atoi(value);
  
          return EVP_PKEY_CTX_set_rsa_keygen_bits(ctx, nbits);
      }
  
      if (strcmp(type, "rsa_keygen_pubexp") == 0) {
          int ret;
  
          BIGNUM *pubexp = NULL;
          if (!BN_asc2bn(&pubexp, value))
              return 0;
          ret = EVP_PKEY_CTX_set1_rsa_keygen_pubexp(ctx, pubexp);
          BN_free(pubexp);
          return ret;
      }
  
      if (strcmp(type, "rsa_keygen_primes") == 0) {
          int nprimes = atoi(value);
  
          return EVP_PKEY_CTX_set_rsa_keygen_primes(ctx, nprimes);
      }
  
      if (strcmp(type, "rsa_mgf1_md") == 0)
          return EVP_PKEY_CTX_md(ctx,
                                 EVP_PKEY_OP_TYPE_SIG | EVP_PKEY_OP_TYPE_CRYPT,
                                 EVP_PKEY_CTRL_RSA_MGF1_MD, value);
  
      if (pkey_ctx_is_pss(ctx)) {
  
          if (strcmp(type, "rsa_pss_keygen_mgf1_md") == 0)
              return EVP_PKEY_CTX_md(ctx, EVP_PKEY_OP_KEYGEN,
                                     EVP_PKEY_CTRL_RSA_MGF1_MD, value);
  
          if (strcmp(type, "rsa_pss_keygen_md") == 0)
              return EVP_PKEY_CTX_md(ctx, EVP_PKEY_OP_KEYGEN,
                                     EVP_PKEY_CTRL_MD, value);
  
          if (strcmp(type, "rsa_pss_keygen_saltlen") == 0) {
              int saltlen = atoi(value);
  
              return EVP_PKEY_CTX_set_rsa_pss_keygen_saltlen(ctx, saltlen);
          }
      }
  
      if (strcmp(type, "rsa_oaep_md") == 0)
          return EVP_PKEY_CTX_md(ctx, EVP_PKEY_OP_TYPE_CRYPT,
                                 EVP_PKEY_CTRL_RSA_OAEP_MD, value);
  
      if (strcmp(type, "rsa_oaep_label") == 0) {
          unsigned char *lab;
          long lablen;
          int ret;
  
          lab = OPENSSL_hexstr2buf(value, &lablen);
          if (!lab)
              return 0;
          ret = EVP_PKEY_CTX_set0_rsa_oaep_label(ctx, lab, lablen);
          if (ret <= 0)
              OPENSSL_free(lab);
          return ret;
      }
  
      return -2;
  }
  
  /* Set PSS parameters when generating a key, if necessary */
  static int rsa_set_pss_param(RSA *rsa, EVP_PKEY_CTX *ctx)
  {
      RSA_PKEY_CTX *rctx = ctx->data;
  
      if (!pkey_ctx_is_pss(ctx))
          return 1;
      /* If all parameters are default values don't set pss */
      if (rctx->md == NULL && rctx->mgf1md == NULL && rctx->saltlen == -2)
          return 1;
      rsa->pss = ossl_rsa_pss_params_create(rctx->md, rctx->mgf1md,
                                            rctx->saltlen == -2
                                            ? 0 : rctx->saltlen);
      if (rsa->pss == NULL)
          return 0;
      return 1;
  }
  
  static int pkey_rsa_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
  {
      RSA *rsa = NULL;
      RSA_PKEY_CTX *rctx = ctx->data;
      BN_GENCB *pcb;
      int ret;
  
      if (rctx->pub_exp == NULL) {
          rctx->pub_exp = BN_new();
          if (rctx->pub_exp == NULL || !BN_set_word(rctx->pub_exp, RSA_F4))
              return 0;
      }
      rsa = RSA_new();
      if (rsa == NULL)
          return 0;
      if (ctx->pkey_gencb) {
          pcb = BN_GENCB_new();
          if (pcb == NULL) {
              RSA_free(rsa);
              return 0;
          }
          evp_pkey_set_cb_translate(pcb, ctx);
      } else {
          pcb = NULL;
      }
      ret = RSA_generate_multi_prime_key(rsa, rctx->nbits, rctx->primes,
                                         rctx->pub_exp, pcb);
      BN_GENCB_free(pcb);
      if (ret > 0 && !rsa_set_pss_param(rsa, ctx)) {
          RSA_free(rsa);
          return 0;
      }
      if (ret > 0)
          EVP_PKEY_assign(pkey, ctx->pmeth->pkey_id, rsa);
      else
          RSA_free(rsa);
      return ret;
  }
  
  static const EVP_PKEY_METHOD rsa_pkey_meth = {
      EVP_PKEY_RSA,
      EVP_PKEY_FLAG_AUTOARGLEN,
      pkey_rsa_init,
      pkey_rsa_copy,
      pkey_rsa_cleanup,
  
      0, 0,
  
      0,
      pkey_rsa_keygen,
  
      0,
      pkey_rsa_sign,
  
      0,
      pkey_rsa_verify,
  
      0,
      pkey_rsa_verifyrecover,
  
      0, 0, 0, 0,
  
      0,
      pkey_rsa_encrypt,
  
      0,
      pkey_rsa_decrypt,
  
      0, 0,
  
      pkey_rsa_ctrl,
      pkey_rsa_ctrl_str
  };
  
  const EVP_PKEY_METHOD *ossl_rsa_pkey_method(void)
  {
      return &rsa_pkey_meth;
  }
  
  /*
   * Called for PSS sign or verify initialisation: checks PSS parameter
   * sanity and sets any restrictions on key usage.
   */
  
  static int pkey_pss_init(EVP_PKEY_CTX *ctx)
  {
      const RSA *rsa;
      RSA_PKEY_CTX *rctx = ctx->data;
      const EVP_MD *md;
      const EVP_MD *mgf1md;
      int min_saltlen, max_saltlen;
  
      /* Should never happen */
      if (!pkey_ctx_is_pss(ctx))
          return 0;
      rsa = EVP_PKEY_get0_RSA(ctx->pkey);
      /* If no restrictions just return */
      if (rsa->pss == NULL)
          return 1;
      /* Get and check parameters */
      if (!ossl_rsa_pss_get_param(rsa->pss, &md, &mgf1md, &min_saltlen))
          return 0;
  
      /* See if minimum salt length exceeds maximum possible */
      max_saltlen = RSA_size(rsa) - EVP_MD_get_size(md);
      if ((RSA_bits(rsa) & 0x7) == 1)
          max_saltlen--;
      if (min_saltlen > max_saltlen) {
          ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_SALT_LENGTH);
          return 0;
      }
  
      rctx->min_saltlen = min_saltlen;
  
      /*
       * Set PSS restrictions as defaults: we can then block any attempt to
       * use invalid values in pkey_rsa_ctrl
       */
  
      rctx->md = md;
      rctx->mgf1md = mgf1md;
      rctx->saltlen = min_saltlen;
  
      return 1;
  }
  
  static const EVP_PKEY_METHOD rsa_pss_pkey_meth = {
      EVP_PKEY_RSA_PSS,
      EVP_PKEY_FLAG_AUTOARGLEN,
      pkey_rsa_init,
      pkey_rsa_copy,
      pkey_rsa_cleanup,
  
      0, 0,
  
      0,
      pkey_rsa_keygen,
  
      pkey_pss_init,
      pkey_rsa_sign,
  
      pkey_pss_init,
      pkey_rsa_verify,
  
      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  
      pkey_rsa_ctrl,
      pkey_rsa_ctrl_str
  };
  
  const EVP_PKEY_METHOD *ossl_rsa_pss_pkey_method(void)
  {
      return &rsa_pss_pkey_meth;
  }
  