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      1 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com)
      2  * All rights reserved.
      3  *
      4  * This package is an SSL implementation written
      5  * by Eric Young (eay (at) cryptsoft.com).
      6  * The implementation was written so as to conform with Netscapes SSL.
      7  *
      8  * This library is free for commercial and non-commercial use as long as
      9  * the following conditions are aheared to.  The following conditions
     10  * apply to all code found in this distribution, be it the RC4, RSA,
     11  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
     12  * included with this distribution is covered by the same copyright terms
     13  * except that the holder is Tim Hudson (tjh (at) cryptsoft.com).
     14  *
     15  * Copyright remains Eric Young's, and as such any Copyright notices in
     16  * the code are not to be removed.
     17  * If this package is used in a product, Eric Young should be given attribution
     18  * as the author of the parts of the library used.
     19  * This can be in the form of a textual message at program startup or
     20  * in documentation (online or textual) provided with the package.
     21  *
     22  * Redistribution and use in source and binary forms, with or without
     23  * modification, are permitted provided that the following conditions
     24  * are met:
     25  * 1. Redistributions of source code must retain the copyright
     26  *    notice, this list of conditions and the following disclaimer.
     27  * 2. Redistributions in binary form must reproduce the above copyright
     28  *    notice, this list of conditions and the following disclaimer in the
     29  *    documentation and/or other materials provided with the distribution.
     30  * 3. All advertising materials mentioning features or use of this software
     31  *    must display the following acknowledgement:
     32  *    "This product includes cryptographic software written by
     33  *     Eric Young (eay (at) cryptsoft.com)"
     34  *    The word 'cryptographic' can be left out if the rouines from the library
     35  *    being used are not cryptographic related :-).
     36  * 4. If you include any Windows specific code (or a derivative thereof) from
     37  *    the apps directory (application code) you must include an acknowledgement:
     38  *    "This product includes software written by Tim Hudson (tjh (at) cryptsoft.com)"
     39  *
     40  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
     41  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     43  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     44  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     45  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     46  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     48  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     49  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     50  * SUCH DAMAGE.
     51  *
     52  * The licence and distribution terms for any publically available version or
     53  * derivative of this code cannot be changed.  i.e. this code cannot simply be
     54  * copied and put under another distribution licence
     55  * [including the GNU Public Licence.] */
     56 
     57 #ifndef OPENSSL_HEADER_RSA_H
     58 #define OPENSSL_HEADER_RSA_H
     59 
     60 #include <openssl/base.h>
     61 
     62 #include <openssl/engine.h>
     63 #include <openssl/ex_data.h>
     64 #include <openssl/thread.h>
     65 
     66 #if defined(__cplusplus)
     67 extern "C" {
     68 #endif
     69 
     70 
     71 /* rsa.h contains functions for handling encryption and signature using RSA. */
     72 
     73 
     74 /* Allocation and destruction. */
     75 
     76 /* RSA_new returns a new, empty RSA object or NULL on error. */
     77 OPENSSL_EXPORT RSA *RSA_new(void);
     78 
     79 /* RSA_new_method acts the same as |RSA_new| but takes an explicit |ENGINE|. */
     80 OPENSSL_EXPORT RSA *RSA_new_method(const ENGINE *engine);
     81 
     82 /* RSA_free decrements the reference count of |rsa| and frees it if the
     83  * reference count drops to zero. */
     84 OPENSSL_EXPORT void RSA_free(RSA *rsa);
     85 
     86 /* RSA_up_ref increments the reference count of |rsa|. */
     87 OPENSSL_EXPORT int RSA_up_ref(RSA *rsa);
     88 
     89 
     90 /* Key generation. */
     91 
     92 /* RSA_generate_key_ex generates a new RSA key where the modulus has size
     93  * |bits| and the public exponent is |e|. If unsure, |RSA_F4| is a good value
     94  * for |e|. If |cb| is not NULL then it is called during the key generation
     95  * process. In addition to the calls documented for |BN_generate_prime_ex|, it
     96  * is called with event=2 when the n'th prime is rejected as unsuitable and
     97  * with event=3 when a suitable value for |p| is found.
     98  *
     99  * It returns one on success or zero on error. */
    100 OPENSSL_EXPORT int RSA_generate_key_ex(RSA *rsa, int bits, BIGNUM *e,
    101                                        BN_GENCB *cb);
    102 
    103 
    104 /* Encryption / Decryption */
    105 
    106 /* Padding types for encryption. */
    107 #define RSA_PKCS1_PADDING 1
    108 #define RSA_NO_PADDING 3
    109 #define RSA_PKCS1_OAEP_PADDING 4
    110 /* RSA_PKCS1_PSS_PADDING can only be used via the EVP interface. */
    111 #define RSA_PKCS1_PSS_PADDING 6
    112 
    113 /* RSA_encrypt encrypts |in_len| bytes from |in| to the public key from |rsa|
    114  * and writes, at most, |max_out| bytes of encrypted data to |out|. The
    115  * |max_out| argument must be, at least, |RSA_size| in order to ensure success.
    116  *
    117  * It returns 1 on success or zero on error.
    118  *
    119  * The |padding| argument must be one of the |RSA_*_PADDING| values. If in
    120  * doubt, |RSA_PKCS1_PADDING| is the most common but |RSA_PKCS1_OAEP_PADDING|
    121  * is the most secure. */
    122 OPENSSL_EXPORT int RSA_encrypt(RSA *rsa, size_t *out_len, uint8_t *out,
    123                                size_t max_out, const uint8_t *in, size_t in_len,
    124                                int padding);
    125 
    126 /* RSA_decrypt decrypts |in_len| bytes from |in| with the private key from
    127  * |rsa| and writes, at most, |max_out| bytes of plaintext to |out|. The
    128  * |max_out| argument must be, at least, |RSA_size| in order to ensure success.
    129  *
    130  * It returns 1 on success or zero on error.
    131  *
    132  * The |padding| argument must be one of the |RSA_*_PADDING| values. If in
    133  * doubt, |RSA_PKCS1_PADDING| is the most common but |RSA_PKCS1_OAEP_PADDING|
    134  * is the most secure. */
    135 OPENSSL_EXPORT int RSA_decrypt(RSA *rsa, size_t *out_len, uint8_t *out,
    136                                size_t max_out, const uint8_t *in, size_t in_len,
    137                                int padding);
    138 
    139 /* RSA_public_encrypt encrypts |flen| bytes from |from| to the public key in
    140  * |rsa| and writes the encrypted data to |to|. The |to| buffer must have at
    141  * least |RSA_size| bytes of space. It returns the number of bytes written, or
    142  * -1 on error. The |padding| argument must be one of the |RSA_*_PADDING|
    143  * values. If in doubt, |RSA_PKCS1_PADDING| is the most common but
    144  * |RSA_PKCS1_OAEP_PADDING| is the most secure.
    145  *
    146  * WARNING: this function is dangerous because it breaks the usual return value
    147  * convention. Use |RSA_encrypt| instead. */
    148 OPENSSL_EXPORT int RSA_public_encrypt(int flen, const uint8_t *from,
    149                                       uint8_t *to, RSA *rsa, int padding);
    150 
    151 /* RSA_private_decrypt decrypts |flen| bytes from |from| with the public key in
    152  * |rsa| and writes the plaintext to |to|. The |to| buffer must have at
    153  * least |RSA_size| bytes of space. It returns the number of bytes written, or
    154  * -1 on error. The |padding| argument must be one of the |RSA_*_PADDING|
    155  * values. If in doubt, |RSA_PKCS1_PADDING| is the most common but
    156  * |RSA_PKCS1_OAEP_PADDING| is the most secure.
    157  *
    158  * WARNING: this function is dangerous because it breaks the usual return value
    159  * convention. Use |RSA_decrypt| instead. */
    160 OPENSSL_EXPORT int RSA_private_decrypt(int flen, const uint8_t *from,
    161                                        uint8_t *to, RSA *rsa, int padding);
    162 
    163 /* RSA_message_index_PKCS1_type_2 performs the first step of a PKCS #1 padding
    164  * check for decryption. If the |from_len| bytes pointed to at |from| are a
    165  * valid PKCS #1 message, it returns one and sets |*out_index| to the start of
    166  * the unpadded message. The unpadded message is a suffix of the input and has
    167  * length |from_len - *out_index|. Otherwise, it returns zero and sets
    168  * |*out_index| to zero. This function runs in time independent of the input
    169  * data and is intended to be used directly to avoid Bleichenbacher's attack.
    170  *
    171  * WARNING: This function behaves differently from the usual OpenSSL convention
    172  * in that it does NOT put an error on the queue in the error case. */
    173 OPENSSL_EXPORT int RSA_message_index_PKCS1_type_2(const uint8_t *from,
    174                                                   size_t from_len,
    175                                                   size_t *out_index);
    176 
    177 
    178 /* Signing / Verification */
    179 
    180 /* RSA_sign signs |in_len| bytes of digest from |in| with |rsa| and writes, at
    181  * most, |RSA_size(rsa)| bytes to |out|. On successful return, the actual
    182  * number of bytes written is written to |*out_len|.
    183  *
    184  * The |hash_nid| argument identifies the hash function used to calculate |in|
    185  * and is embedded in the resulting signature. For example, it might be
    186  * |NID_sha256|.
    187  *
    188  * It returns 1 on success and zero on error. */
    189 OPENSSL_EXPORT int RSA_sign(int hash_nid, const uint8_t *in,
    190                             unsigned int in_len, uint8_t *out,
    191                             unsigned int *out_len, RSA *rsa);
    192 
    193 /* RSA_sign_raw signs |in_len| bytes from |in| with the public key from |rsa|
    194  * and writes, at most, |max_out| bytes of signature data to |out|. The
    195  * |max_out| argument must be, at least, |RSA_size| in order to ensure success.
    196  *
    197  * It returns 1 on success or zero on error.
    198  *
    199  * The |padding| argument must be one of the |RSA_*_PADDING| values. If in
    200  * doubt, |RSA_PKCS1_PADDING| is the most common. */
    201 OPENSSL_EXPORT int RSA_sign_raw(RSA *rsa, size_t *out_len, uint8_t *out,
    202                                 size_t max_out, const uint8_t *in,
    203                                 size_t in_len, int padding);
    204 
    205 /* RSA_verify verifies that |sig_len| bytes from |sig| are a valid, PKCS#1
    206  * signature of |msg_len| bytes at |msg| by |rsa|.
    207  *
    208  * The |hash_nid| argument identifies the hash function used to calculate |in|
    209  * and is embedded in the resulting signature in order to prevent hash
    210  * confusion attacks. For example, it might be |NID_sha256|.
    211  *
    212  * It returns one if the signature is valid and zero otherwise.
    213  *
    214  * WARNING: this differs from the original, OpenSSL function which additionally
    215  * returned -1 on error. */
    216 OPENSSL_EXPORT int RSA_verify(int hash_nid, const uint8_t *msg, size_t msg_len,
    217                               const uint8_t *sig, size_t sig_len, RSA *rsa);
    218 
    219 /* RSA_verify_raw verifies |in_len| bytes of signature from |in| using the
    220  * public key from |rsa| and writes, at most, |max_out| bytes of plaintext to
    221  * |out|. The |max_out| argument must be, at least, |RSA_size| in order to
    222  * ensure success.
    223  *
    224  * It returns 1 on success or zero on error.
    225  *
    226  * The |padding| argument must be one of the |RSA_*_PADDING| values. If in
    227  * doubt, |RSA_PKCS1_PADDING| is the most common. */
    228 OPENSSL_EXPORT int RSA_verify_raw(RSA *rsa, size_t *out_len, uint8_t *out,
    229                                   size_t max_out, const uint8_t *in,
    230                                   size_t in_len, int padding);
    231 
    232 /* RSA_private_encrypt encrypts |flen| bytes from |from| with the private key in
    233  * |rsa| and writes the encrypted data to |to|. The |to| buffer must have at
    234  * least |RSA_size| bytes of space. It returns the number of bytes written, or
    235  * -1 on error. The |padding| argument must be one of the |RSA_*_PADDING|
    236  * values. If in doubt, |RSA_PKCS1_PADDING| is the most common.
    237  *
    238  * WARNING: this function is dangerous because it breaks the usual return value
    239  * convention. Use |RSA_sign_raw| instead. */
    240 OPENSSL_EXPORT int RSA_private_encrypt(int flen, const uint8_t *from,
    241                                        uint8_t *to, RSA *rsa, int padding);
    242 
    243 /* RSA_private_encrypt verifies |flen| bytes of signature from |from| using the
    244  * public key in |rsa| and writes the plaintext to |to|. The |to| buffer must
    245  * have at least |RSA_size| bytes of space. It returns the number of bytes
    246  * written, or -1 on error. The |padding| argument must be one of the
    247  * |RSA_*_PADDING| values. If in doubt, |RSA_PKCS1_PADDING| is the most common.
    248  *
    249  * WARNING: this function is dangerous because it breaks the usual return value
    250  * convention. Use |RSA_verify_raw| instead. */
    251 OPENSSL_EXPORT int RSA_public_decrypt(int flen, const uint8_t *from,
    252                                       uint8_t *to, RSA *rsa, int padding);
    253 
    254 
    255 /* Utility functions. */
    256 
    257 /* RSA_size returns the number of bytes in the modulus, which is also the size
    258  * of a signature or encrypted value using |rsa|. */
    259 OPENSSL_EXPORT unsigned RSA_size(const RSA *rsa);
    260 
    261 /* RSA_is_opaque returns one if |rsa| is opaque and doesn't expose its key
    262  * material. Otherwise it returns zero. */
    263 OPENSSL_EXPORT int RSA_is_opaque(const RSA *rsa);
    264 
    265 /* RSA_supports_digest returns one if |rsa| supports signing digests
    266  * of type |md|. Otherwise it returns zero. */
    267 OPENSSL_EXPORT int RSA_supports_digest(const RSA *rsa, const EVP_MD *md);
    268 
    269 /* RSAPublicKey_dup allocates a fresh |RSA| and copies the private key from
    270  * |rsa| into it. It returns the fresh |RSA| object, or NULL on error. */
    271 OPENSSL_EXPORT RSA *RSAPublicKey_dup(const RSA *rsa);
    272 
    273 /* RSAPrivateKey_dup allocates a fresh |RSA| and copies the private key from
    274  * |rsa| into it. It returns the fresh |RSA| object, or NULL on error. */
    275 OPENSSL_EXPORT RSA *RSAPrivateKey_dup(const RSA *rsa);
    276 
    277 /* RSA_check_key performs basic validatity tests on |rsa|. It returns one if
    278  * they pass and zero otherwise. Opaque keys and public keys always pass. If it
    279  * returns zero then a more detailed error is available on the error queue. */
    280 OPENSSL_EXPORT int RSA_check_key(const RSA *rsa);
    281 
    282 /* RSA_recover_crt_params uses |rsa->n|, |rsa->d| and |rsa->e| in order to
    283  * calculate the two primes used and thus the precomputed, CRT values. These
    284  * values are set in the |p|, |q|, |dmp1|, |dmq1| and |iqmp| members of |rsa|,
    285  * which must be |NULL| on entry. It returns one on success and zero
    286  * otherwise. */
    287 OPENSSL_EXPORT int RSA_recover_crt_params(RSA *rsa);
    288 
    289 /* RSA_verify_PKCS1_PSS_mgf1 verifies that |EM| is a correct PSS padding of
    290  * |mHash|, where |mHash| is a digest produced by |Hash|. |EM| must point to
    291  * exactly |RSA_size(rsa)| bytes of data. The |mgf1Hash| argument specifies the
    292  * hash function for generating the mask. If NULL, |Hash| is used. The |sLen|
    293  * argument specifies the expected salt length in bytes. If |sLen| is -1 then
    294  * the salt length is the same as the hash length. If -2, then the salt length
    295  * is maximal and is taken from the size of |EM|.
    296  *
    297  * It returns one on success or zero on error. */
    298 OPENSSL_EXPORT int RSA_verify_PKCS1_PSS_mgf1(RSA *rsa, const uint8_t *mHash,
    299                                              const EVP_MD *Hash,
    300                                              const EVP_MD *mgf1Hash,
    301                                              const uint8_t *EM, int sLen);
    302 
    303 /* RSA_padding_add_PKCS1_PSS_mgf1 writes a PSS padding of |mHash| to |EM|,
    304  * where |mHash| is a digest produced by |Hash|. |RSA_size(rsa)| bytes of
    305  * output will be written to |EM|. The |mgf1Hash| argument specifies the hash
    306  * function for generating the mask. If NULL, |Hash| is used. The |sLen|
    307  * argument specifies the expected salt length in bytes. If |sLen| is -1 then
    308  * the salt length is the same as the hash length. If -2, then the salt length
    309  * is maximal given the space in |EM|.
    310  *
    311  * It returns one on success or zero on error. */
    312 OPENSSL_EXPORT int RSA_padding_add_PKCS1_PSS_mgf1(RSA *rsa, uint8_t *EM,
    313                                                   const uint8_t *mHash,
    314                                                   const EVP_MD *Hash,
    315                                                   const EVP_MD *mgf1Hash,
    316                                                   int sLen);
    317 
    318 
    319 /* ASN.1 functions. */
    320 
    321 /* d2i_RSAPublicKey parses an ASN.1, DER-encoded, RSA public key from |len|
    322  * bytes at |*inp|. If |out| is not NULL then, on exit, a pointer to the result
    323  * is in |*out|. If |*out| is already non-NULL on entry then the result is
    324  * written directly into |*out|, otherwise a fresh |RSA| is allocated. On
    325  * successful exit, |*inp| is advanced past the DER structure. It returns the
    326  * result or NULL on error. */
    327 OPENSSL_EXPORT RSA *d2i_RSAPublicKey(RSA **out, const uint8_t **inp, long len);
    328 
    329 /* i2d_RSAPublicKey marshals |in| to an ASN.1, DER structure. If |outp| is not
    330  * NULL then the result is written to |*outp| and |*outp| is advanced just past
    331  * the output. It returns the number of bytes in the result, whether written or
    332  * not, or a negative value on error. */
    333 OPENSSL_EXPORT int i2d_RSAPublicKey(const RSA *in, uint8_t **outp);
    334 
    335 /* d2i_RSAPrivateKey parses an ASN.1, DER-encoded, RSA private key from |len|
    336  * bytes at |*inp|. If |out| is not NULL then, on exit, a pointer to the result
    337  * is in |*out|. If |*out| is already non-NULL on entry then the result is
    338  * written directly into |*out|, otherwise a fresh |RSA| is allocated. On
    339  * successful exit, |*inp| is advanced past the DER structure. It returns the
    340  * result or NULL on error. */
    341 OPENSSL_EXPORT RSA *d2i_RSAPrivateKey(RSA **out, const uint8_t **inp, long len);
    342 
    343 /* i2d_RSAPrivateKey marshals |in| to an ASN.1, DER structure. If |outp| is not
    344  * NULL then the result is written to |*outp| and |*outp| is advanced just past
    345  * the output. It returns the number of bytes in the result, whether written or
    346  * not, or a negative value on error. */
    347 OPENSSL_EXPORT int i2d_RSAPrivateKey(const RSA *in, uint8_t **outp);
    348 
    349 
    350 /* ex_data functions.
    351  *
    352  * See |ex_data.h| for details. */
    353 
    354 OPENSSL_EXPORT int RSA_get_ex_new_index(long argl, void *argp,
    355                                         CRYPTO_EX_new *new_func,
    356                                         CRYPTO_EX_dup *dup_func,
    357                                         CRYPTO_EX_free *free_func);
    358 OPENSSL_EXPORT int RSA_set_ex_data(RSA *r, int idx, void *arg);
    359 OPENSSL_EXPORT void *RSA_get_ex_data(const RSA *r, int idx);
    360 
    361 /* RSA_FLAG_OPAQUE specifies that this RSA_METHOD does not expose its key
    362  * material. This may be set if, for instance, it is wrapping some other crypto
    363  * API, like a platform key store. */
    364 #define RSA_FLAG_OPAQUE 1
    365 
    366 /* RSA_FLAG_CACHE_PUBLIC causes a precomputed Montgomery context to be created,
    367  * on demand, for the public key operations. */
    368 #define RSA_FLAG_CACHE_PUBLIC 2
    369 
    370 /* RSA_FLAG_CACHE_PRIVATE causes a precomputed Montgomery context to be
    371  * created, on demand, for the private key operations. */
    372 #define RSA_FLAG_CACHE_PRIVATE 4
    373 
    374 /* RSA_FLAG_NO_BLINDING disables blinding of private operations. */
    375 #define RSA_FLAG_NO_BLINDING 8
    376 
    377 /* RSA_FLAG_EXT_PKEY means that private key operations will be handled by
    378  * |mod_exp| and that they do not depend on the private key components being
    379  * present: for example a key stored in external hardware. */
    380 #define RSA_FLAG_EXT_PKEY 0x20
    381 
    382 /* RSA_FLAG_SIGN_VER causes the |sign| and |verify| functions of |rsa_meth_st|
    383  * to be called when set. */
    384 #define RSA_FLAG_SIGN_VER 0x40
    385 
    386 
    387 /* RSA public exponent values. */
    388 
    389 #define RSA_3 0x3
    390 #define RSA_F4 0x10001
    391 
    392 
    393 /* Deprecated functions. */
    394 
    395 /* RSA_blinding_on returns one. */
    396 OPENSSL_EXPORT int RSA_blinding_on(RSA *rsa, BN_CTX *ctx);
    397 
    398 
    399 struct rsa_meth_st {
    400   struct openssl_method_common_st common;
    401 
    402   void *app_data;
    403 
    404   int (*init)(RSA *rsa);
    405   int (*finish)(RSA *rsa);
    406 
    407   /* size returns the size of the RSA modulus in bytes. */
    408   size_t (*size)(const RSA *rsa);
    409 
    410   int (*sign)(int type, const uint8_t *m, unsigned int m_length,
    411               uint8_t *sigret, unsigned int *siglen, const RSA *rsa);
    412 
    413   int (*verify)(int dtype, const uint8_t *m, unsigned int m_length,
    414                 const uint8_t *sigbuf, unsigned int siglen, const RSA *rsa);
    415 
    416 
    417   /* These functions mirror the |RSA_*| functions of the same name. */
    418   int (*encrypt)(RSA *rsa, size_t *out_len, uint8_t *out, size_t max_out,
    419                  const uint8_t *in, size_t in_len, int padding);
    420   int (*sign_raw)(RSA *rsa, size_t *out_len, uint8_t *out, size_t max_out,
    421                   const uint8_t *in, size_t in_len, int padding);
    422 
    423   int (*decrypt)(RSA *rsa, size_t *out_len, uint8_t *out, size_t max_out,
    424                  const uint8_t *in, size_t in_len, int padding);
    425   int (*verify_raw)(RSA *rsa, size_t *out_len, uint8_t *out, size_t max_out,
    426                     const uint8_t *in, size_t in_len, int padding);
    427 
    428   /* private_transform takes a big-endian integer from |in|, calculates the
    429    * d'th power of it, modulo the RSA modulus and writes the result as a
    430    * big-endian integer to |out|. Both |in| and |out| are |len| bytes long and
    431    * |len| is always equal to |RSA_size(rsa)|. If the result of the transform
    432    * can be represented in fewer than |len| bytes, then |out| must be zero
    433    * padded on the left.
    434    *
    435    * It returns one on success and zero otherwise.
    436    *
    437    * RSA decrypt and sign operations will call this, thus an ENGINE might wish
    438    * to override it in order to avoid having to implement the padding
    439    * functionality demanded by those, higher level, operations. */
    440   int (*private_transform)(RSA *rsa, uint8_t *out, const uint8_t *in,
    441                            size_t len);
    442 
    443   int (*mod_exp)(BIGNUM *r0, const BIGNUM *I, RSA *rsa,
    444                  BN_CTX *ctx); /* Can be null */
    445   int (*bn_mod_exp)(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
    446                     const BIGNUM *m, BN_CTX *ctx,
    447                     BN_MONT_CTX *m_ctx);
    448 
    449   int flags;
    450 
    451   int (*keygen)(RSA *rsa, int bits, BIGNUM *e, BN_GENCB *cb);
    452 
    453   /* supports_digest returns one if |rsa| supports digests of type
    454    * |md|. If null, it is assumed that all digests are supported. */
    455   int (*supports_digest)(const RSA *rsa, const EVP_MD *md);
    456 };
    457 
    458 
    459 /* Private functions. */
    460 
    461 typedef struct bn_blinding_st BN_BLINDING;
    462 
    463 struct rsa_st {
    464   /* version is only used during ASN.1 (de)serialisation. */
    465   long version;
    466   RSA_METHOD *meth;
    467 
    468   BIGNUM *n;
    469   BIGNUM *e;
    470   BIGNUM *d;
    471   BIGNUM *p;
    472   BIGNUM *q;
    473   BIGNUM *dmp1;
    474   BIGNUM *dmq1;
    475   BIGNUM *iqmp;
    476   /* be careful using this if the RSA structure is shared */
    477   CRYPTO_EX_DATA ex_data;
    478   CRYPTO_refcount_t references;
    479   int flags;
    480 
    481   CRYPTO_MUTEX lock;
    482 
    483   /* Used to cache montgomery values. The creation of these values is protected
    484    * by |lock|. */
    485   BN_MONT_CTX *_method_mod_n;
    486   BN_MONT_CTX *_method_mod_p;
    487   BN_MONT_CTX *_method_mod_q;
    488 
    489   /* num_blindings contains the size of the |blindings| and |blindings_inuse|
    490    * arrays. This member and the |blindings_inuse| array are protected by
    491    * |lock|. */
    492   unsigned num_blindings;
    493   /* blindings is an array of BN_BLINDING structures that can be reserved by a
    494    * thread by locking |lock| and changing the corresponding element in
    495    * |blindings_inuse| from 0 to 1. */
    496   BN_BLINDING **blindings;
    497   unsigned char *blindings_inuse;
    498 };
    499 
    500 
    501 #if defined(__cplusplus)
    502 }  /* extern C */
    503 #endif
    504 
    505 #define RSA_F_BN_BLINDING_convert_ex 100
    506 #define RSA_F_BN_BLINDING_create_param 101
    507 #define RSA_F_BN_BLINDING_invert_ex 102
    508 #define RSA_F_BN_BLINDING_new 103
    509 #define RSA_F_BN_BLINDING_update 104
    510 #define RSA_F_RSA_check_key 105
    511 #define RSA_F_RSA_new_method 106
    512 #define RSA_F_RSA_padding_add_PKCS1_OAEP_mgf1 107
    513 #define RSA_F_RSA_padding_add_PKCS1_PSS_mgf1 108
    514 #define RSA_F_RSA_padding_add_PKCS1_type_1 109
    515 #define RSA_F_RSA_padding_add_PKCS1_type_2 110
    516 #define RSA_F_RSA_padding_add_none 111
    517 #define RSA_F_RSA_padding_check_PKCS1_OAEP_mgf1 112
    518 #define RSA_F_RSA_padding_check_PKCS1_type_1 113
    519 #define RSA_F_RSA_padding_check_PKCS1_type_2 114
    520 #define RSA_F_RSA_padding_check_none 115
    521 #define RSA_F_RSA_recover_crt_params 116
    522 #define RSA_F_RSA_sign 117
    523 #define RSA_F_RSA_verify 118
    524 #define RSA_F_RSA_verify_PKCS1_PSS_mgf1 119
    525 #define RSA_F_decrypt 120
    526 #define RSA_F_encrypt 121
    527 #define RSA_F_keygen 122
    528 #define RSA_F_pkcs1_prefixed_msg 123
    529 #define RSA_F_private_transform 124
    530 #define RSA_F_rsa_setup_blinding 125
    531 #define RSA_F_sign_raw 126
    532 #define RSA_F_verify_raw 127
    533 #define RSA_R_BAD_E_VALUE 100
    534 #define RSA_R_BAD_FIXED_HEADER_DECRYPT 101
    535 #define RSA_R_BAD_PAD_BYTE_COUNT 102
    536 #define RSA_R_BAD_RSA_PARAMETERS 103
    537 #define RSA_R_BAD_SIGNATURE 104
    538 #define RSA_R_BLOCK_TYPE_IS_NOT_01 105
    539 #define RSA_R_BN_NOT_INITIALIZED 106
    540 #define RSA_R_CRT_PARAMS_ALREADY_GIVEN 107
    541 #define RSA_R_CRT_VALUES_INCORRECT 108
    542 #define RSA_R_DATA_LEN_NOT_EQUAL_TO_MOD_LEN 109
    543 #define RSA_R_DATA_TOO_LARGE 110
    544 #define RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE 111
    545 #define RSA_R_DATA_TOO_LARGE_FOR_MODULUS 112
    546 #define RSA_R_DATA_TOO_SMALL 113
    547 #define RSA_R_DATA_TOO_SMALL_FOR_KEY_SIZE 114
    548 #define RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY 115
    549 #define RSA_R_D_E_NOT_CONGRUENT_TO_1 116
    550 #define RSA_R_EMPTY_PUBLIC_KEY 117
    551 #define RSA_R_FIRST_OCTET_INVALID 118
    552 #define RSA_R_INCONSISTENT_SET_OF_CRT_VALUES 119
    553 #define RSA_R_INTERNAL_ERROR 120
    554 #define RSA_R_INVALID_MESSAGE_LENGTH 121
    555 #define RSA_R_KEY_SIZE_TOO_SMALL 122
    556 #define RSA_R_LAST_OCTET_INVALID 123
    557 #define RSA_R_MODULUS_TOO_LARGE 124
    558 #define RSA_R_NO_PUBLIC_EXPONENT 125
    559 #define RSA_R_NULL_BEFORE_BLOCK_MISSING 126
    560 #define RSA_R_N_NOT_EQUAL_P_Q 127
    561 #define RSA_R_OAEP_DECODING_ERROR 128
    562 #define RSA_R_ONLY_ONE_OF_P_Q_GIVEN 129
    563 #define RSA_R_OUTPUT_BUFFER_TOO_SMALL 130
    564 #define RSA_R_PADDING_CHECK_FAILED 131
    565 #define RSA_R_PKCS_DECODING_ERROR 132
    566 #define RSA_R_SLEN_CHECK_FAILED 133
    567 #define RSA_R_SLEN_RECOVERY_FAILED 134
    568 #define RSA_R_TOO_LONG 135
    569 #define RSA_R_TOO_MANY_ITERATIONS 136
    570 #define RSA_R_UNKNOWN_ALGORITHM_TYPE 137
    571 #define RSA_R_UNKNOWN_PADDING_TYPE 138
    572 #define RSA_R_VALUE_MISSING 139
    573 #define RSA_R_WRONG_SIGNATURE_LENGTH 140
    574 
    575 #endif  /* OPENSSL_HEADER_RSA_H */
    576