openssl/crypto/rsa/rsa_locl.h
Sebastian Andrzej Siewior cac19d19e7 rsa: Do not allow less than 512 bit RSA keys
As per documentation, the RSA keys should not be smaller than 64bit (the
documentation mentions something about a quirk in the prime generation
algorithm). I am adding check into the code which used to be 16 for some
reason.
My primary motivation is to get rid of the last sentence in the
documentation which suggest that typical keys have 1024 bits (instead
updating it to the now default 2048).
I *assume* that keys less than the 2048 bits (say 512) are used for
education purposes.
The 512 bits as the minimum have been suggested by Bernd Edlinger.

Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>

Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4547)
2017-12-11 12:53:07 +01:00

133 lines
4.9 KiB
C

/*
* Copyright 2006-2017 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (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
*/
#include <openssl/rsa.h>
#include "internal/refcount.h"
#define RSA_MAX_PRIME_NUM 16
#define RSA_MIN_PRIME_SIZE 64
#define RSA_MIN_MODULUS_BITS 512
typedef struct rsa_prime_info_st {
BIGNUM *r;
BIGNUM *d;
BIGNUM *t;
/* save product of primes prior to this one */
BIGNUM *pp;
BN_MONT_CTX *m;
} RSA_PRIME_INFO;
DECLARE_ASN1_ITEM(RSA_PRIME_INFO)
DEFINE_STACK_OF(RSA_PRIME_INFO)
struct rsa_st {
/*
* The first parameter is used to pickup errors where this is passed
* instead of an EVP_PKEY, it is set to 0
*/
int pad;
int32_t version;
const RSA_METHOD *meth;
/* functional reference if 'meth' is ENGINE-provided */
ENGINE *engine;
BIGNUM *n;
BIGNUM *e;
BIGNUM *d;
BIGNUM *p;
BIGNUM *q;
BIGNUM *dmp1;
BIGNUM *dmq1;
BIGNUM *iqmp;
/* for multi-prime RSA, defined in RFC 8017 */
STACK_OF(RSA_PRIME_INFO) *prime_infos;
/* If a PSS only key this contains the parameter restrictions */
RSA_PSS_PARAMS *pss;
/* be careful using this if the RSA structure is shared */
CRYPTO_EX_DATA ex_data;
CRYPTO_REF_COUNT references;
int flags;
/* Used to cache montgomery values */
BN_MONT_CTX *_method_mod_n;
BN_MONT_CTX *_method_mod_p;
BN_MONT_CTX *_method_mod_q;
/*
* all BIGNUM values are actually in the following data, if it is not
* NULL
*/
char *bignum_data;
BN_BLINDING *blinding;
BN_BLINDING *mt_blinding;
CRYPTO_RWLOCK *lock;
};
struct rsa_meth_st {
char *name;
int (*rsa_pub_enc) (int flen, const unsigned char *from,
unsigned char *to, RSA *rsa, int padding);
int (*rsa_pub_dec) (int flen, const unsigned char *from,
unsigned char *to, RSA *rsa, int padding);
int (*rsa_priv_enc) (int flen, const unsigned char *from,
unsigned char *to, RSA *rsa, int padding);
int (*rsa_priv_dec) (int flen, const unsigned char *from,
unsigned char *to, RSA *rsa, int padding);
/* Can be null */
int (*rsa_mod_exp) (BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx);
/* Can be null */
int (*bn_mod_exp) (BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx);
/* called at new */
int (*init) (RSA *rsa);
/* called at free */
int (*finish) (RSA *rsa);
/* RSA_METHOD_FLAG_* things */
int flags;
/* may be needed! */
char *app_data;
/*
* New sign and verify functions: some libraries don't allow arbitrary
* data to be signed/verified: this allows them to be used. Note: for
* this to work the RSA_public_decrypt() and RSA_private_encrypt() should
* *NOT* be used RSA_sign(), RSA_verify() should be used instead.
*/
int (*rsa_sign) (int type,
const unsigned char *m, unsigned int m_length,
unsigned char *sigret, unsigned int *siglen,
const RSA *rsa);
int (*rsa_verify) (int dtype, const unsigned char *m,
unsigned int m_length, const unsigned char *sigbuf,
unsigned int siglen, const RSA *rsa);
/*
* If this callback is NULL, the builtin software RSA key-gen will be
* used. This is for behavioural compatibility whilst the code gets
* rewired, but one day it would be nice to assume there are no such
* things as "builtin software" implementations.
*/
int (*rsa_keygen) (RSA *rsa, int bits, BIGNUM *e, BN_GENCB *cb);
int (*rsa_multi_prime_keygen) (RSA *rsa, int bits, int primes,
BIGNUM *e, BN_GENCB *cb);
};
extern int int_rsa_verify(int dtype, const unsigned char *m,
unsigned int m_len, unsigned char *rm,
size_t *prm_len, const unsigned char *sigbuf,
size_t siglen, RSA *rsa);
/* Macros to test if a pkey or ctx is for a PSS key */
#define pkey_is_pss(pkey) (pkey->ameth->pkey_id == EVP_PKEY_RSA_PSS)
#define pkey_ctx_is_pss(ctx) (ctx->pmeth->pkey_id == EVP_PKEY_RSA_PSS)
RSA_PSS_PARAMS *rsa_pss_params_create(const EVP_MD *sigmd,
const EVP_MD *mgf1md, int saltlen);
int rsa_pss_get_param(const RSA_PSS_PARAMS *pss, const EVP_MD **pmd,
const EVP_MD **pmgf1md, int *psaltlen);
/* internal function to clear and free multi-prime parameters */
void rsa_multip_info_free_ex(RSA_PRIME_INFO *pinfo);
void rsa_multip_info_free(RSA_PRIME_INFO *pinfo);
RSA_PRIME_INFO *rsa_multip_info_new(void);
int rsa_multip_calc_product(RSA *rsa);
int rsa_multip_cap(int bits);