Commit 2514fa79 authored by Dr. Stephen Henson's avatar Dr. Stephen Henson
Browse files

Add functions returning security bits. 

Add functions to return the "bits of security" for various public key
algorithms. Based on SP800-57.
parent 4563da1d

crypto/asn1/ameth_lib.c

+7 −0
Original line number Diff line number Diff line
@@ -462,3 +462,10 @@ void EVP_PKEY_asn1_set_ctrl(EVP_PKEY_ASN1_METHOD *ameth, 
	{

	ameth->pkey_ctrl = pkey_ctrl;

	}



void EVP_PKEY_asn1_set_security_bits(EVP_PKEY_ASN1_METHOD *ameth,

				int (*pkey_security_bits)(const EVP_PKEY *pk))

	{

	ameth->pkey_security_bits = pkey_security_bits;

	}

crypto/asn1/asn1_locl.h

+1 −0
Original line number Diff line number Diff line
@@ -122,6 +122,7 @@ struct evp_pkey_asn1_method_st 


	int (*pkey_size)(const EVP_PKEY *pk);

	int (*pkey_bits)(const EVP_PKEY *pk);

	int (*pkey_security_bits)(const EVP_PKEY *pk);



	int (*param_decode)(EVP_PKEY *pkey,

				const unsigned char **pder, int derlen);

crypto/bn/bn.h

+1 −0
Original line number Diff line number Diff line
@@ -420,6 +420,7 @@ int BN_rand_range(BIGNUM *rnd, const BIGNUM *range); 
int	BN_pseudo_rand_range(BIGNUM *rnd, const BIGNUM *range);

int	BN_num_bits(const BIGNUM *a);

int	BN_num_bits_word(BN_ULONG l);

int	BN_security_bits(int L, int N);

BIGNUM *BN_new(void);

void	BN_init(BIGNUM *);

void	BN_clear_free(BIGNUM *a);

crypto/bn/bn_lib.c

+25 −0
Original line number Diff line number Diff line
@@ -880,3 +880,28 @@ void BN_consttime_swap(BN_ULONG condition, BIGNUM *a, BIGNUM *b, int nwords) 
	}

#undef BN_CONSTTIME_SWAP

}



/* Bits of security, see SP800-57 */



int BN_security_bits(int L, int N)

	{

	int secbits, bits;

	if (L >= 15360)

		secbits = 256;

	else if (L >= 7690)

		secbits = 192;

	else if (L >= 3072)

		secbits = 128;

	else if (L >= 2048)

		secbits = 112;

	else if (L >= 1024)

		secbits = 80;

	else

		return 0;

	if (N == -1)

		return secbits;

	bits = N / 2;

	if (bits < 80)

		return 0;

	return bits >= secbits ? secbits : bits;

	}

crypto/cmac/cm_ameth.c

+1 −1
Original line number Diff line number Diff line
@@ -87,7 +87,7 @@ const EVP_PKEY_ASN1_METHOD cmac_asn1_meth = 
	0,0,0,



	cmac_size,

	0,

	0, 0,

	0,0,0,0,0,0,0,



	cmac_key_free,