[thirdparty/openssl.git] / crypto / rsa / rsa_sign.c

/*
 * Copyright 1995-2021 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 <stdio.h>
#include "internal/cryptlib.h"
#include <openssl/bn.h>
#include <openssl/rsa.h>
#include <openssl/objects.h>
#include <openssl/x509.h>
#include "crypto/x509.h"
#ifndef OPENSSL_NO_MD2
# include <openssl/md2.h> /* uses MD2_DIGEST_LENGTH */
#endif
#ifndef OPENSSL_NO_MD4
# include <openssl/md4.h> /* uses MD4_DIGEST_LENGTH */
#endif
#ifndef OPENSSL_NO_MD5
# include <openssl/md5.h> /* uses MD5_DIGEST_LENGTH */
#endif
#ifndef OPENSSL_NO_MDC2
# include <openssl/mdc2.h> /* uses MDC2_DIGEST_LENGTH */
#endif
#ifndef OPENSSL_NO_RMD160
# include <openssl/ripemd.h> /* uses RIPEMD160_DIGEST_LENGTH */
#endif
#include <openssl/sha.h> /* uses SHA???_DIGEST_LENGTH */
#include "crypto/rsa.h"
#include "rsa_local.h"

/*
 * The general purpose ASN1 code is not available inside the FIPS provider.
 * To remove the dependency RSASSA-PKCS1-v1_5 DigestInfo encodings can be
 * treated as a special case by pregenerating the required ASN1 encoding.
 * This encoding will also be shared by the default provider.
 *
 * The EMSA-PKCS1-v1_5 encoding method includes an ASN.1 value of type
 * DigestInfo, where the type DigestInfo has the syntax
 *
 *     DigestInfo ::= SEQUENCE {
 *         digestAlgorithm DigestAlgorithm,
 *         digest OCTET STRING
 *     }
 *
 *     DigestAlgorithm ::= AlgorithmIdentifier {
 *         {PKCS1-v1-5DigestAlgorithms}
 *     }
 *
 * The AlgorithmIdentifier is a sequence containing the digest OID and
 * parameters (a value of type NULL).
 *
 * The ENCODE_DIGESTINFO_SHA() and ENCODE_DIGESTINFO_MD() macros define an
 * initialized array containing the DER encoded DigestInfo for the specified
 * SHA or MD digest. The content of the OCTET STRING is not included.
 * |name| is the digest name.
 * |n| is last byte in the encoded OID for the digest.
 * |sz| is the digest length in bytes. It must not be greater than 110.
 */

#define ASN1_SEQUENCE 0x30
#define ASN1_OCTET_STRING 0x04
#define ASN1_NULL 0x05
#define ASN1_OID 0x06

/* SHA OIDs are of the form: (2 16 840 1 101 3 4 2 |n|) */
#define ENCODE_DIGESTINFO_SHA(name, n, sz)                                     \
static const unsigned char digestinfo_##name##_der[] = {                       \
    ASN1_SEQUENCE, 0x11 + sz,                                                  \
      ASN1_SEQUENCE, 0x0d,                                                     \
        ASN1_OID, 0x09, 2 * 40 + 16, 0x86, 0x48, 1, 101, 3, 4, 2, n,           \
        ASN1_NULL, 0x00,                                                       \
      ASN1_OCTET_STRING, sz                                                    \
};

/* MD2, MD4 and MD5 OIDs are of the form: (1 2 840 113549 2 |n|) */
#define ENCODE_DIGESTINFO_MD(name, n, sz)                                      \
static const unsigned char digestinfo_##name##_der[] = {                       \
    ASN1_SEQUENCE, 0x10 + sz,                                                  \
      ASN1_SEQUENCE, 0x0c,                                                     \
        ASN1_OID, 0x08, 1 * 40 + 2, 0x86, 0x48, 0x86, 0xf7, 0x0d, 2, n,        \
        ASN1_NULL, 0x00,                                                       \
      ASN1_OCTET_STRING, sz                                                    \
};

#ifndef FIPS_MODULE
# ifndef OPENSSL_NO_MD2
ENCODE_DIGESTINFO_MD(md2, 0x02, MD2_DIGEST_LENGTH)
# endif
# ifndef OPENSSL_NO_MD4
ENCODE_DIGESTINFO_MD(md4, 0x03, MD4_DIGEST_LENGTH)
# endif
# ifndef OPENSSL_NO_MD5
ENCODE_DIGESTINFO_MD(md5, 0x05, MD5_DIGEST_LENGTH)
# endif
# ifndef OPENSSL_NO_MDC2
/* MDC-2 (2 5 8 3 101) */
static const unsigned char digestinfo_mdc2_der[] = {
    ASN1_SEQUENCE, 0x0c + MDC2_DIGEST_LENGTH,
      ASN1_SEQUENCE, 0x08,
        ASN1_OID, 0x04, 2 * 40 + 5, 8, 3, 101,
        ASN1_NULL, 0x00,
      ASN1_OCTET_STRING, MDC2_DIGEST_LENGTH
};
# endif
# ifndef OPENSSL_NO_RMD160
/* RIPEMD160 (1 3 36 3 2 1) */
static const unsigned char digestinfo_ripemd160_der[] = {
    ASN1_SEQUENCE, 0x0d + RIPEMD160_DIGEST_LENGTH,
      ASN1_SEQUENCE, 0x09,
        ASN1_OID, 0x05, 1 * 40 + 3, 36, 3, 2, 1,
        ASN1_NULL, 0x00,
      ASN1_OCTET_STRING, RIPEMD160_DIGEST_LENGTH
};
# endif
#endif /* FIPS_MODULE */

/* SHA-1 (1 3 14 3 2 26) */
static const unsigned char digestinfo_sha1_der[] = {
    ASN1_SEQUENCE, 0x0d + SHA_DIGEST_LENGTH,
      ASN1_SEQUENCE, 0x09,
        ASN1_OID, 0x05, 1 * 40 + 3, 14, 3, 2, 26,
        ASN1_NULL, 0x00,
      ASN1_OCTET_STRING, SHA_DIGEST_LENGTH
};

ENCODE_DIGESTINFO_SHA(sha256, 0x01, SHA256_DIGEST_LENGTH)
ENCODE_DIGESTINFO_SHA(sha384, 0x02, SHA384_DIGEST_LENGTH)
ENCODE_DIGESTINFO_SHA(sha512, 0x03, SHA512_DIGEST_LENGTH)
ENCODE_DIGESTINFO_SHA(sha224, 0x04, SHA224_DIGEST_LENGTH)
ENCODE_DIGESTINFO_SHA(sha512_224, 0x05, SHA224_DIGEST_LENGTH)
ENCODE_DIGESTINFO_SHA(sha512_256, 0x06, SHA256_DIGEST_LENGTH)
ENCODE_DIGESTINFO_SHA(sha3_224, 0x07, SHA224_DIGEST_LENGTH)
ENCODE_DIGESTINFO_SHA(sha3_256, 0x08, SHA256_DIGEST_LENGTH)
ENCODE_DIGESTINFO_SHA(sha3_384, 0x09, SHA384_DIGEST_LENGTH)
ENCODE_DIGESTINFO_SHA(sha3_512, 0x0a, SHA512_DIGEST_LENGTH)

#define MD_CASE(name)                                                          \
    case NID_##name:                                                           \
        *len = sizeof(digestinfo_##name##_der);                                \
        return digestinfo_##name##_der;

const unsigned char *ossl_rsa_digestinfo_encoding(int md_nid, size_t *len)
{
    switch (md_nid) {
#ifndef FIPS_MODULE
# ifndef OPENSSL_NO_MDC2
    MD_CASE(mdc2)
# endif
# ifndef OPENSSL_NO_MD2
    MD_CASE(md2)
# endif
# ifndef OPENSSL_NO_MD4
    MD_CASE(md4)
# endif
# ifndef OPENSSL_NO_MD5
    MD_CASE(md5)
# endif
# ifndef OPENSSL_NO_RMD160
    MD_CASE(ripemd160)
# endif
#endif /* FIPS_MODULE */
    MD_CASE(sha1)
    MD_CASE(sha224)
    MD_CASE(sha256)
    MD_CASE(sha384)
    MD_CASE(sha512)
    MD_CASE(sha512_224)
    MD_CASE(sha512_256)
    MD_CASE(sha3_224)
    MD_CASE(sha3_256)
    MD_CASE(sha3_384)
    MD_CASE(sha3_512)
    default:
        return NULL;
    }
}

#define MD_NID_CASE(name, sz)                                                  \
    case NID_##name:                                                           \
        return sz;

static int digest_sz_from_nid(int nid)
{
    switch (nid) {
#ifndef FIPS_MODULE
# ifndef OPENSSL_NO_MDC2
    MD_NID_CASE(mdc2, MDC2_DIGEST_LENGTH)
# endif
# ifndef OPENSSL_NO_MD2
    MD_NID_CASE(md2, MD2_DIGEST_LENGTH)
# endif
# ifndef OPENSSL_NO_MD4
    MD_NID_CASE(md4, MD4_DIGEST_LENGTH)
# endif
# ifndef OPENSSL_NO_MD5
    MD_NID_CASE(md5, MD5_DIGEST_LENGTH)
# endif
# ifndef OPENSSL_NO_RMD160
    MD_NID_CASE(ripemd160, RIPEMD160_DIGEST_LENGTH)
# endif
#endif /* FIPS_MODULE */
    MD_NID_CASE(sha1, SHA_DIGEST_LENGTH)
    MD_NID_CASE(sha224, SHA224_DIGEST_LENGTH)
    MD_NID_CASE(sha256, SHA256_DIGEST_LENGTH)
    MD_NID_CASE(sha384, SHA384_DIGEST_LENGTH)
    MD_NID_CASE(sha512, SHA512_DIGEST_LENGTH)
    MD_NID_CASE(sha512_224, SHA224_DIGEST_LENGTH)
    MD_NID_CASE(sha512_256, SHA256_DIGEST_LENGTH)
    MD_NID_CASE(sha3_224, SHA224_DIGEST_LENGTH)
    MD_NID_CASE(sha3_256, SHA256_DIGEST_LENGTH)
    MD_NID_CASE(sha3_384, SHA384_DIGEST_LENGTH)
    MD_NID_CASE(sha3_512, SHA512_DIGEST_LENGTH)
    default:
        return 0;
    }
}


/* Size of an SSL signature: MD5+SHA1 */
#define SSL_SIG_LENGTH  36

/*
 * Encodes a DigestInfo prefix of hash |type| and digest |m|, as
 * described in EMSA-PKCS1-v1_5-ENCODE, RFC 3447 section 9.2 step 2. This
 * encodes the DigestInfo (T and tLen) but does not add the padding.
 *
 * On success, it returns one and sets |*out| to a newly allocated buffer
 * containing the result and |*out_len| to its length. The caller must free
 * |*out| with OPENSSL_free(). Otherwise, it returns zero.
 */
static int encode_pkcs1(unsigned char **out, size_t *out_len, int type,
                        const unsigned char *m, size_t m_len)
{
    size_t di_prefix_len, dig_info_len;
    const unsigned char *di_prefix;
    unsigned char *dig_info;

    if (type == NID_undef) {
        ERR_raise(ERR_LIB_RSA, RSA_R_UNKNOWN_ALGORITHM_TYPE);
        return 0;
    }
    di_prefix = ossl_rsa_digestinfo_encoding(type, &di_prefix_len);
    if (di_prefix == NULL) {
        ERR_raise(ERR_LIB_RSA,
                  RSA_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD);
        return 0;
    }
    dig_info_len = di_prefix_len + m_len;
    dig_info = OPENSSL_malloc(dig_info_len);
    if (dig_info == NULL) {
        ERR_raise(ERR_LIB_RSA, ERR_R_MALLOC_FAILURE);
        return 0;
    }
    memcpy(dig_info, di_prefix, di_prefix_len);
    memcpy(dig_info + di_prefix_len, m, m_len);

    *out = dig_info;
    *out_len = dig_info_len;
    return 1;
}

int RSA_sign(int type, const unsigned char *m, unsigned int m_len,
             unsigned char *sigret, unsigned int *siglen, RSA *rsa)
{
    int encrypt_len, ret = 0;
    size_t encoded_len = 0;
    unsigned char *tmps = NULL;
    const unsigned char *encoded = NULL;

#ifndef FIPS_MODULE
    if (rsa->meth->rsa_sign != NULL)
        return rsa->meth->rsa_sign(type, m, m_len, sigret, siglen, rsa);
#endif /* FIPS_MODULE */

    /* Compute the encoded digest. */
    if (type == NID_md5_sha1) {
        /*
         * NID_md5_sha1 corresponds to the MD5/SHA1 combination in TLS 1.1 and
         * earlier. It has no DigestInfo wrapper but otherwise is
         * RSASSA-PKCS1-v1_5.
         */
        if (m_len != SSL_SIG_LENGTH) {
            ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_MESSAGE_LENGTH);
            return 0;
        }
        encoded_len = SSL_SIG_LENGTH;
        encoded = m;
    } else {
        if (!encode_pkcs1(&tmps, &encoded_len, type, m, m_len))
            goto err;
        encoded = tmps;
    }

    if (encoded_len + RSA_PKCS1_PADDING_SIZE > (size_t)RSA_size(rsa)) {
        ERR_raise(ERR_LIB_RSA, RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY);
        goto err;
    }
    encrypt_len = RSA_private_encrypt((int)encoded_len, encoded, sigret, rsa,
                                      RSA_PKCS1_PADDING);
    if (encrypt_len <= 0)
        goto err;

    *siglen = encrypt_len;
    ret = 1;

err:
    OPENSSL_clear_free(tmps, encoded_len);
    return ret;
}

/*
 * Verify an RSA signature in |sigbuf| using |rsa|.
 * |type| is the NID of the digest algorithm to use.
 * If |rm| is NULL, it verifies the signature for digest |m|, otherwise
 * it recovers the digest from the signature, writing the digest to |rm| and
 * the length to |*prm_len|.
 *
 * It returns one on successful verification or zero otherwise.
 */
int ossl_rsa_verify(int type, const unsigned char *m, unsigned int m_len,
                    unsigned char *rm, size_t *prm_len,
                    const unsigned char *sigbuf, size_t siglen, RSA *rsa)
{
    int len, ret = 0;
    size_t decrypt_len, encoded_len = 0;
    unsigned char *decrypt_buf = NULL, *encoded = NULL;

    if (siglen != (size_t)RSA_size(rsa)) {
        ERR_raise(ERR_LIB_RSA, RSA_R_WRONG_SIGNATURE_LENGTH);
        return 0;
    }

    /* Recover the encoded digest. */
    decrypt_buf = OPENSSL_malloc(siglen);
    if (decrypt_buf == NULL) {
        ERR_raise(ERR_LIB_RSA, ERR_R_MALLOC_FAILURE);
        goto err;
    }

    len = RSA_public_decrypt((int)siglen, sigbuf, decrypt_buf, rsa,
                             RSA_PKCS1_PADDING);
    if (len <= 0)
        goto err;
    decrypt_len = len;

#ifndef FIPS_MODULE
    if (type == NID_md5_sha1) {
        /*
         * NID_md5_sha1 corresponds to the MD5/SHA1 combination in TLS 1.1 and
         * earlier. It has no DigestInfo wrapper but otherwise is
         * RSASSA-PKCS1-v1_5.
         */
        if (decrypt_len != SSL_SIG_LENGTH) {
            ERR_raise(ERR_LIB_RSA, RSA_R_BAD_SIGNATURE);
            goto err;
        }

        if (rm != NULL) {
            memcpy(rm, decrypt_buf, SSL_SIG_LENGTH);
            *prm_len = SSL_SIG_LENGTH;
        } else {
            if (m_len != SSL_SIG_LENGTH) {
                ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_MESSAGE_LENGTH);
                goto err;
            }

            if (memcmp(decrypt_buf, m, SSL_SIG_LENGTH) != 0) {
                ERR_raise(ERR_LIB_RSA, RSA_R_BAD_SIGNATURE);
                goto err;
            }
        }
    } else if (type == NID_mdc2 && decrypt_len == 2 + 16
               && decrypt_buf[0] == 0x04 && decrypt_buf[1] == 0x10) {
        /*
         * Oddball MDC2 case: signature can be OCTET STRING. check for correct
         * tag and length octets.
         */
        if (rm != NULL) {
            memcpy(rm, decrypt_buf + 2, 16);
            *prm_len = 16;
        } else {
            if (m_len != 16) {
                ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_MESSAGE_LENGTH);
                goto err;
            }

            if (memcmp(m, decrypt_buf + 2, 16) != 0) {
                ERR_raise(ERR_LIB_RSA, RSA_R_BAD_SIGNATURE);
                goto err;
            }
        }
    } else
#endif /* FIPS_MODULE */
    {
        /*
         * If recovering the digest, extract a digest-sized output from the end
         * of |decrypt_buf| for |encode_pkcs1|, then compare the decryption
         * output as in a standard verification.
         */
        if (rm != NULL) {
            len = digest_sz_from_nid(type);

            if (len <= 0)
                goto err;
            m_len = (unsigned int)len;
            if (m_len > decrypt_len) {
                ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_DIGEST_LENGTH);
                goto err;
            }
            m = decrypt_buf + decrypt_len - m_len;
        }

        /* Construct the encoded digest and ensure it matches. */
        if (!encode_pkcs1(&encoded, &encoded_len, type, m, m_len))
            goto err;

        if (encoded_len != decrypt_len
                || memcmp(encoded, decrypt_buf, encoded_len) != 0) {
            ERR_raise(ERR_LIB_RSA, RSA_R_BAD_SIGNATURE);
            goto err;
        }

        /* Output the recovered digest. */
        if (rm != NULL) {
            memcpy(rm, m, m_len);
            *prm_len = m_len;
        }
    }

    ret = 1;

err:
    OPENSSL_clear_free(encoded, encoded_len);
    OPENSSL_clear_free(decrypt_buf, siglen);
    return ret;
}

int RSA_verify(int type, const unsigned char *m, unsigned int m_len,
               const unsigned char *sigbuf, unsigned int siglen, RSA *rsa)
{

    if (rsa->meth->rsa_verify != NULL)
        return rsa->meth->rsa_verify(type, m, m_len, sigbuf, siglen, rsa);

    return ossl_rsa_verify(type, m, m_len, NULL, NULL, sigbuf, siglen, rsa);
}
Commit	Line	Data
2039c421	1	/*
3c2bdd7d	2	* Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
d02b48c6	3	*
2a7b6f39	4	* Licensed under the Apache License 2.0 (the "License"). You may not use
2039c421 RS	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
d02b48c6 RE	8	*/
d02b48c6 RE	9
c5f87134 P	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
d02b48c6	16	#include <stdio.h>
b39fc560	17	#include "internal/cryptlib.h"
ec577822 BM	18	#include <openssl/bn.h>
	19	#include <openssl/rsa.h>
	20	#include <openssl/objects.h>
	21	#include <openssl/x509.h>
25f2138b	22	#include "crypto/x509.h"
169e422e SL	23	#ifndef OPENSSL_NO_MD2
	24	# include <openssl/md2.h> /* uses MD2_DIGEST_LENGTH */
	25	#endif
6f4b7663 RL	26	#ifndef OPENSSL_NO_MD4
	27	# include <openssl/md4.h> /* uses MD4_DIGEST_LENGTH */
	28	#endif
169e422e SL	29	#ifndef OPENSSL_NO_MD5
	30	# include <openssl/md5.h> /* uses MD5_DIGEST_LENGTH */
	31	#endif
	32	#ifndef OPENSSL_NO_MDC2
	33	# include <openssl/mdc2.h> /* uses MDC2_DIGEST_LENGTH */
	34	#endif
6f4b7663 RL	35	#ifndef OPENSSL_NO_RMD160
	36	# include <openssl/ripemd.h> /* uses RIPEMD160_DIGEST_LENGTH */
	37	#endif
169e422e	38	#include <openssl/sha.h> /* uses SHA???_DIGEST_LENGTH */
6f4b7663	39	#include "crypto/rsa.h"
706457b7	40	#include "rsa_local.h"
d02b48c6	41
169e422e SL	42	/*
	43	* The general purpose ASN1 code is not available inside the FIPS provider.
	44	* To remove the dependency RSASSA-PKCS1-v1_5 DigestInfo encodings can be
	45	* treated as a special case by pregenerating the required ASN1 encoding.
	46	* This encoding will also be shared by the default provider.
	47	*
	48	* The EMSA-PKCS1-v1_5 encoding method includes an ASN.1 value of type
	49	* DigestInfo, where the type DigestInfo has the syntax
	50	*
	51	* DigestInfo ::= SEQUENCE {
	52	* digestAlgorithm DigestAlgorithm,
	53	* digest OCTET STRING
	54	* }
	55	*
	56	* DigestAlgorithm ::= AlgorithmIdentifier {
	57	* {PKCS1-v1-5DigestAlgorithms}
	58	* }
	59	*
	60	* The AlgorithmIdentifier is a sequence containing the digest OID and
	61	* parameters (a value of type NULL).
	62	*
	63	* The ENCODE_DIGESTINFO_SHA() and ENCODE_DIGESTINFO_MD() macros define an
	64	* initialized array containing the DER encoded DigestInfo for the specified
	65	* SHA or MD digest. The content of the OCTET STRING is not included.
	66	* \|name\| is the digest name.
	67	* \|n\| is last byte in the encoded OID for the digest.
	68	* \|sz\| is the digest length in bytes. It must not be greater than 110.
	69	*/
	70
	71	#define ASN1_SEQUENCE 0x30
	72	#define ASN1_OCTET_STRING 0x04
	73	#define ASN1_NULL 0x05
	74	#define ASN1_OID 0x06
	75
	76	/* SHA OIDs are of the form: (2 16 840 1 101 3 4 2 \|n\|) */
	77	#define ENCODE_DIGESTINFO_SHA(name, n, sz) \
	78	static const unsigned char digestinfo_##name##_der[] = { \
	79	ASN1_SEQUENCE, 0x11 + sz, \
	80	ASN1_SEQUENCE, 0x0d, \
	81	ASN1_OID, 0x09, 2 * 40 + 16, 0x86, 0x48, 1, 101, 3, 4, 2, n, \
	82	ASN1_NULL, 0x00, \
	83	ASN1_OCTET_STRING, sz \
	84	};
	85
6f4b7663	86	/* MD2, MD4 and MD5 OIDs are of the form: (1 2 840 113549 2 \|n\|) */
169e422e SL	87	#define ENCODE_DIGESTINFO_MD(name, n, sz) \
	88	static const unsigned char digestinfo_##name##_der[] = { \
	89	ASN1_SEQUENCE, 0x10 + sz, \
	90	ASN1_SEQUENCE, 0x0c, \
	91	ASN1_OID, 0x08, 1 * 40 + 2, 0x86, 0x48, 0x86, 0xf7, 0x0d, 2, n, \
	92	ASN1_NULL, 0x00, \
	93	ASN1_OCTET_STRING, sz \
	94	};
	95
f844f9eb	96	#ifndef FIPS_MODULE
169e422e SL	97	# ifndef OPENSSL_NO_MD2
	98	ENCODE_DIGESTINFO_MD(md2, 0x02, MD2_DIGEST_LENGTH)
	99	# endif
6f4b7663 RL	100	# ifndef OPENSSL_NO_MD4
	101	ENCODE_DIGESTINFO_MD(md4, 0x03, MD4_DIGEST_LENGTH)
	102	# endif
169e422e SL	103	# ifndef OPENSSL_NO_MD5
	104	ENCODE_DIGESTINFO_MD(md5, 0x05, MD5_DIGEST_LENGTH)
	105	# endif
	106	# ifndef OPENSSL_NO_MDC2
	107	/* MDC-2 (2 5 8 3 101) */
	108	static const unsigned char digestinfo_mdc2_der[] = {
	109	ASN1_SEQUENCE, 0x0c + MDC2_DIGEST_LENGTH,
	110	ASN1_SEQUENCE, 0x08,
	111	ASN1_OID, 0x04, 2 * 40 + 5, 8, 3, 101,
	112	ASN1_NULL, 0x00,
	113	ASN1_OCTET_STRING, MDC2_DIGEST_LENGTH
	114	};
	115	# endif
6f4b7663	116	# ifndef OPENSSL_NO_RMD160
172daa7f	117	/* RIPEMD160 (1 3 36 3 2 1) */
6f4b7663	118	static const unsigned char digestinfo_ripemd160_der[] = {
172daa7f RL	119	ASN1_SEQUENCE, 0x0d + RIPEMD160_DIGEST_LENGTH,
	120	ASN1_SEQUENCE, 0x09,
	121	ASN1_OID, 0x05, 1 * 40 + 3, 36, 3, 2, 1,
6f4b7663 RL	122	ASN1_NULL, 0x00,
	123	ASN1_OCTET_STRING, RIPEMD160_DIGEST_LENGTH
	124	};
	125	# endif
f844f9eb	126	#endif /* FIPS_MODULE */
6f4b7663	127
169e422e SL	128	/* SHA-1 (1 3 14 3 2 26) */
	129	static const unsigned char digestinfo_sha1_der[] = {
	130	ASN1_SEQUENCE, 0x0d + SHA_DIGEST_LENGTH,
	131	ASN1_SEQUENCE, 0x09,
	132	ASN1_OID, 0x05, 1 * 40 + 3, 14, 3, 2, 26,
	133	ASN1_NULL, 0x00,
	134	ASN1_OCTET_STRING, SHA_DIGEST_LENGTH
	135	};
	136
169e422e SL	137	ENCODE_DIGESTINFO_SHA(sha256, 0x01, SHA256_DIGEST_LENGTH)
	138	ENCODE_DIGESTINFO_SHA(sha384, 0x02, SHA384_DIGEST_LENGTH)
	139	ENCODE_DIGESTINFO_SHA(sha512, 0x03, SHA512_DIGEST_LENGTH)
	140	ENCODE_DIGESTINFO_SHA(sha224, 0x04, SHA224_DIGEST_LENGTH)
	141	ENCODE_DIGESTINFO_SHA(sha512_224, 0x05, SHA224_DIGEST_LENGTH)
	142	ENCODE_DIGESTINFO_SHA(sha512_256, 0x06, SHA256_DIGEST_LENGTH)
	143	ENCODE_DIGESTINFO_SHA(sha3_224, 0x07, SHA224_DIGEST_LENGTH)
	144	ENCODE_DIGESTINFO_SHA(sha3_256, 0x08, SHA256_DIGEST_LENGTH)
	145	ENCODE_DIGESTINFO_SHA(sha3_384, 0x09, SHA384_DIGEST_LENGTH)
	146	ENCODE_DIGESTINFO_SHA(sha3_512, 0x0a, SHA512_DIGEST_LENGTH)
	147
	148	#define MD_CASE(name) \
	149	case NID_##name: \
	150	*len = sizeof(digestinfo_##name##_der); \
	151	return digestinfo_##name##_der;
	152
23b2fc0b	153	const unsigned char ossl_rsa_digestinfo_encoding(int md_nid, size_t len)
169e422e	154	{
6f4b7663	155	switch (md_nid) {
f844f9eb	156	#ifndef FIPS_MODULE
169e422e SL	157	# ifndef OPENSSL_NO_MDC2
	158	MD_CASE(mdc2)
	159	# endif
	160	# ifndef OPENSSL_NO_MD2
	161	MD_CASE(md2)
	162	# endif
6f4b7663 RL	163	# ifndef OPENSSL_NO_MD4
	164	MD_CASE(md4)
	165	# endif
169e422e SL	166	# ifndef OPENSSL_NO_MD5
	167	MD_CASE(md5)
	168	# endif
6f4b7663 RL	169	# ifndef OPENSSL_NO_RMD160
	170	MD_CASE(ripemd160)
	171	# endif
f844f9eb	172	#endif /* FIPS_MODULE */
6f4b7663	173	MD_CASE(sha1)
169e422e SL	174	MD_CASE(sha224)
	175	MD_CASE(sha256)
	176	MD_CASE(sha384)
	177	MD_CASE(sha512)
	178	MD_CASE(sha512_224)
	179	MD_CASE(sha512_256)
	180	MD_CASE(sha3_224)
	181	MD_CASE(sha3_256)
	182	MD_CASE(sha3_384)
	183	MD_CASE(sha3_512)
	184	default:
	185	return NULL;
	186	}
	187	}
	188
d16d0b71 SL	189	#define MD_NID_CASE(name, sz) \
	190	case NID_##name: \
	191	return sz;
	192
	193	static int digest_sz_from_nid(int nid)
	194	{
	195	switch (nid) {
f844f9eb	196	#ifndef FIPS_MODULE
d16d0b71 SL	197	# ifndef OPENSSL_NO_MDC2
	198	MD_NID_CASE(mdc2, MDC2_DIGEST_LENGTH)
	199	# endif
	200	# ifndef OPENSSL_NO_MD2
	201	MD_NID_CASE(md2, MD2_DIGEST_LENGTH)
	202	# endif
	203	# ifndef OPENSSL_NO_MD4
	204	MD_NID_CASE(md4, MD4_DIGEST_LENGTH)
	205	# endif
	206	# ifndef OPENSSL_NO_MD5
	207	MD_NID_CASE(md5, MD5_DIGEST_LENGTH)
	208	# endif
	209	# ifndef OPENSSL_NO_RMD160
	210	MD_NID_CASE(ripemd160, RIPEMD160_DIGEST_LENGTH)
	211	# endif
f844f9eb	212	#endif /* FIPS_MODULE */
d16d0b71 SL	213	MD_NID_CASE(sha1, SHA_DIGEST_LENGTH)
	214	MD_NID_CASE(sha224, SHA224_DIGEST_LENGTH)
	215	MD_NID_CASE(sha256, SHA256_DIGEST_LENGTH)
	216	MD_NID_CASE(sha384, SHA384_DIGEST_LENGTH)
	217	MD_NID_CASE(sha512, SHA512_DIGEST_LENGTH)
	218	MD_NID_CASE(sha512_224, SHA224_DIGEST_LENGTH)
	219	MD_NID_CASE(sha512_256, SHA256_DIGEST_LENGTH)
	220	MD_NID_CASE(sha3_224, SHA224_DIGEST_LENGTH)
	221	MD_NID_CASE(sha3_256, SHA256_DIGEST_LENGTH)
	222	MD_NID_CASE(sha3_384, SHA384_DIGEST_LENGTH)
	223	MD_NID_CASE(sha3_512, SHA512_DIGEST_LENGTH)
	224	default:
	225	return 0;
	226	}
	227	}
	228
	229
1c80019a	230	/* Size of an SSL signature: MD5+SHA1 */
0f113f3e	231	#define SSL_SIG_LENGTH 36
1c80019a	232
608a0264	233	/*
169e422e	234	* Encodes a DigestInfo prefix of hash \|type\| and digest \|m\|, as
608a0264 DB	235	* described in EMSA-PKCS1-v1_5-ENCODE, RFC 3447 section 9.2 step 2. This
	236	* encodes the DigestInfo (T and tLen) but does not add the padding.
	237	*
	238	* On success, it returns one and sets \|*out\| to a newly allocated buffer
	239	* containing the result and \|*out_len\| to its length. The caller must free
169e422e	240	* \|*out\| with OPENSSL_free(). Otherwise, it returns zero.
608a0264	241	*/
169e422e SL	242	static int encode_pkcs1(unsigned char *out, size_t out_len, int type,
169e422e SL	243	const unsigned char *m, size_t m_len)
0f113f3e	244	{
169e422e SL	245	size_t di_prefix_len, dig_info_len;
	246	const unsigned char *di_prefix;
	247	unsigned char *dig_info;
	248
	249	if (type == NID_undef) {
9311d0c4	250	ERR_raise(ERR_LIB_RSA, RSA_R_UNKNOWN_ALGORITHM_TYPE);
608a0264 DB	251	return 0;
608a0264 DB	252	}
23b2fc0b	253	di_prefix = ossl_rsa_digestinfo_encoding(type, &di_prefix_len);
169e422e	254	if (di_prefix == NULL) {
9311d0c4 RL	255	ERR_raise(ERR_LIB_RSA,
9311d0c4 RL	256	RSA_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD);
608a0264 DB	257	return 0;
608a0264 DB	258	}
169e422e SL	259	dig_info_len = di_prefix_len + m_len;
	260	dig_info = OPENSSL_malloc(dig_info_len);
	261	if (dig_info == NULL) {
9311d0c4	262	ERR_raise(ERR_LIB_RSA, ERR_R_MALLOC_FAILURE);
608a0264	263	return 0;
169e422e SL	264	}
	265	memcpy(dig_info, di_prefix, di_prefix_len);
	266	memcpy(dig_info + di_prefix_len, m, m_len);
608a0264	267
169e422e SL	268	*out = dig_info;
169e422e SL	269	*out_len = dig_info_len;
608a0264 DB	270	return 1;
	271	}
	272
	273	int RSA_sign(int type, const unsigned char *m, unsigned int m_len,
	274	unsigned char sigret, unsigned int siglen, RSA *rsa)
	275	{
169e422e SL	276	int encrypt_len, ret = 0;
169e422e SL	277	size_t encoded_len = 0;
608a0264 DB	278	unsigned char *tmps = NULL;
	279	const unsigned char *encoded = NULL;
	280
f844f9eb	281	#ifndef FIPS_MODULE
169e422e	282	if (rsa->meth->rsa_sign != NULL)
0f113f3e	283	return rsa->meth->rsa_sign(type, m, m_len, sigret, siglen, rsa);
f844f9eb	284	#endif /* FIPS_MODULE */
608a0264 DB	285
608a0264 DB	286	/* Compute the encoded digest. */
0f113f3e	287	if (type == NID_md5_sha1) {
608a0264 DB	288	/*
	289	* NID_md5_sha1 corresponds to the MD5/SHA1 combination in TLS 1.1 and
	290	* earlier. It has no DigestInfo wrapper but otherwise is
	291	* RSASSA-PKCS1-v1_5.
	292	*/
0f113f3e	293	if (m_len != SSL_SIG_LENGTH) {
9311d0c4	294	ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_MESSAGE_LENGTH);
608a0264	295	return 0;
0f113f3e	296	}
608a0264 DB	297	encoded_len = SSL_SIG_LENGTH;
608a0264 DB	298	encoded = m;
0f113f3e	299	} else {
608a0264 DB	300	if (!encode_pkcs1(&tmps, &encoded_len, type, m, m_len))
	301	goto err;
	302	encoded = tmps;
0f113f3e	303	}
608a0264	304
169e422e	305	if (encoded_len + RSA_PKCS1_PADDING_SIZE > (size_t)RSA_size(rsa)) {
9311d0c4	306	ERR_raise(ERR_LIB_RSA, RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY);
608a0264	307	goto err;
0f113f3e	308	}
169e422e	309	encrypt_len = RSA_private_encrypt((int)encoded_len, encoded, sigret, rsa,
608a0264 DB	310	RSA_PKCS1_PADDING);
	311	if (encrypt_len <= 0)
	312	goto err;
d02b48c6	313
608a0264 DB	314	*siglen = encrypt_len;
	315	ret = 1;
	316
	317	err:
169e422e	318	OPENSSL_clear_free(tmps, encoded_len);
0f113f3e MC	319	return ret;
0f113f3e MC	320	}
1cfd255c	321
608a0264	322	/*
169e422e SL	323	* Verify an RSA signature in \|sigbuf\| using \|rsa\|.
	324	* \|type\| is the NID of the digest algorithm to use.
	325	* If \|rm\| is NULL, it verifies the signature for digest \|m\|, otherwise
	326	* it recovers the digest from the signature, writing the digest to \|rm\| and
	327	* the length to \|*prm_len\|.
	328	*
	329	* It returns one on successful verification or zero otherwise.
608a0264	330	*/
4158b0dc SL	331	int ossl_rsa_verify(int type, const unsigned char *m, unsigned int m_len,
	332	unsigned char rm, size_t prm_len,
	333	const unsigned char sigbuf, size_t siglen, RSA rsa)
0f113f3e	334	{
169e422e SL	335	int len, ret = 0;
169e422e SL	336	size_t decrypt_len, encoded_len = 0;
608a0264	337	unsigned char decrypt_buf = NULL, encoded = NULL;
d02b48c6	338
608a0264	339	if (siglen != (size_t)RSA_size(rsa)) {
9311d0c4	340	ERR_raise(ERR_LIB_RSA, RSA_R_WRONG_SIGNATURE_LENGTH);
608a0264	341	return 0;
0f113f3e	342	}
d02b48c6	343
608a0264 DB	344	/* Recover the encoded digest. */
	345	decrypt_buf = OPENSSL_malloc(siglen);
	346	if (decrypt_buf == NULL) {
9311d0c4	347	ERR_raise(ERR_LIB_RSA, ERR_R_MALLOC_FAILURE);
0f113f3e MC	348	goto err;
0f113f3e MC	349	}
d02b48c6	350
169e422e SL	351	len = RSA_public_decrypt((int)siglen, sigbuf, decrypt_buf, rsa,
	352	RSA_PKCS1_PADDING);
	353	if (len <= 0)
0f113f3e	354	goto err;
169e422e	355	decrypt_len = len;
608a0264	356
f844f9eb	357	#ifndef FIPS_MODULE
608a0264 DB	358	if (type == NID_md5_sha1) {
	359	/*
	360	* NID_md5_sha1 corresponds to the MD5/SHA1 combination in TLS 1.1 and
	361	* earlier. It has no DigestInfo wrapper but otherwise is
	362	* RSASSA-PKCS1-v1_5.
	363	*/
	364	if (decrypt_len != SSL_SIG_LENGTH) {
9311d0c4	365	ERR_raise(ERR_LIB_RSA, RSA_R_BAD_SIGNATURE);
608a0264	366	goto err;
dffe5109	367	}
b79aa05e	368
608a0264 DB	369	if (rm != NULL) {
	370	memcpy(rm, decrypt_buf, SSL_SIG_LENGTH);
	371	*prm_len = SSL_SIG_LENGTH;
	372	} else {
	373	if (m_len != SSL_SIG_LENGTH) {
9311d0c4	374	ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_MESSAGE_LENGTH);
608a0264 DB	375	goto err;
608a0264 DB	376	}
b79aa05e	377
608a0264	378	if (memcmp(decrypt_buf, m, SSL_SIG_LENGTH) != 0) {
9311d0c4	379	ERR_raise(ERR_LIB_RSA, RSA_R_BAD_SIGNATURE);
608a0264 DB	380	goto err;
608a0264 DB	381	}
0f113f3e	382	}
608a0264 DB	383	} else if (type == NID_mdc2 && decrypt_len == 2 + 16
	384	&& decrypt_buf[0] == 0x04 && decrypt_buf[1] == 0x10) {
	385	/*
	386	* Oddball MDC2 case: signature can be OCTET STRING. check for correct
	387	* tag and length octets.
	388	*/
	389	if (rm != NULL) {
	390	memcpy(rm, decrypt_buf + 2, 16);
	391	*prm_len = 16;
	392	} else {
	393	if (m_len != 16) {
9311d0c4	394	ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_MESSAGE_LENGTH);
608a0264 DB	395	goto err;
608a0264 DB	396	}
b79aa05e	397
608a0264	398	if (memcmp(m, decrypt_buf + 2, 16) != 0) {
9311d0c4	399	ERR_raise(ERR_LIB_RSA, RSA_R_BAD_SIGNATURE);
608a0264 DB	400	goto err;
	401	}
	402	}
d16d0b71	403	} else
f844f9eb	404	#endif /* FIPS_MODULE */
d16d0b71	405	{
0f113f3e	406	/*
608a0264 DB	407	* If recovering the digest, extract a digest-sized output from the end
	408	* of \|decrypt_buf\| for \|encode_pkcs1\|, then compare the decryption
	409	* output as in a standard verification.
0f113f3e	410	*/
608a0264	411	if (rm != NULL) {
d16d0b71	412	len = digest_sz_from_nid(type);
608a0264	413
169e422e SL	414	if (len <= 0)
	415	goto err;
	416	m_len = (unsigned int)len;
	417	if (m_len > decrypt_len) {
9311d0c4	418	ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_DIGEST_LENGTH);
608a0264 DB	419	goto err;
	420	}
	421	m = decrypt_buf + decrypt_len - m_len;
0f113f3e	422	}
d02b48c6	423
608a0264 DB	424	/* Construct the encoded digest and ensure it matches. */
	425	if (!encode_pkcs1(&encoded, &encoded_len, type, m, m_len))
	426	goto err;
dfeab068	427
608a0264	428	if (encoded_len != decrypt_len
169e422e	429	\|\| memcmp(encoded, decrypt_buf, encoded_len) != 0) {
9311d0c4	430	ERR_raise(ERR_LIB_RSA, RSA_R_BAD_SIGNATURE);
3d0cf918	431	goto err;
0f113f3e	432	}
608a0264 DB	433
	434	/* Output the recovered digest. */
	435	if (rm != NULL) {
	436	memcpy(rm, m, m_len);
	437	*prm_len = m_len;
	438	}
0f113f3e	439	}
608a0264 DB	440
	441	ret = 1;
	442
	443	err:
169e422e	444	OPENSSL_clear_free(encoded, encoded_len);
608a0264 DB	445	OPENSSL_clear_free(decrypt_buf, siglen);
608a0264 DB	446	return ret;
0f113f3e	447	}
d02b48c6	448
608a0264	449	int RSA_verify(int type, const unsigned char *m, unsigned int m_len,
0f113f3e MC	450	const unsigned char sigbuf, unsigned int siglen, RSA rsa)
0f113f3e MC	451	{
b2a97be7	452
169e422e	453	if (rsa->meth->rsa_verify != NULL)
608a0264	454	return rsa->meth->rsa_verify(type, m, m_len, sigbuf, siglen, rsa);
b2a97be7	455
4158b0dc	456	return ossl_rsa_verify(type, m, m_len, NULL, NULL, sigbuf, siglen, rsa);
0f113f3e	457	}