dolphin/Externals/mbedtls/library/rsa.c
Tillmann Karras 9872473f70 mbedTLS: add version 2.1.1
PolarSSL has been renamed to "mbed TLS" and version 2.0 dropped backwards
compatibility. This commit adds only the necessary files without any
modifications, so it doesn't compile yet.
2015-09-25 03:11:48 +02:00

1695 lines
49 KiB
C

/*
* The RSA public-key cryptosystem
*
* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* This file is part of mbed TLS (https://tls.mbed.org)
*/
/*
* RSA was designed by Ron Rivest, Adi Shamir and Len Adleman.
*
* http://theory.lcs.mit.edu/~rivest/rsapaper.pdf
* http://www.cacr.math.uwaterloo.ca/hac/about/chap8.pdf
*/
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#if defined(MBEDTLS_RSA_C)
#include "mbedtls/rsa.h"
#include "mbedtls/oid.h"
#include <string.h>
#if defined(MBEDTLS_PKCS1_V21)
#include "mbedtls/md.h"
#endif
#if defined(MBEDTLS_PKCS1_V15) && !defined(__OpenBSD__)
#include <stdlib.h>
#endif
#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#include <stdio.h>
#define mbedtls_printf printf
#define mbedtls_calloc calloc
#define mbedtls_free free
#endif
/*
* Initialize an RSA context
*/
void mbedtls_rsa_init( mbedtls_rsa_context *ctx,
int padding,
int hash_id )
{
memset( ctx, 0, sizeof( mbedtls_rsa_context ) );
mbedtls_rsa_set_padding( ctx, padding, hash_id );
#if defined(MBEDTLS_THREADING_C)
mbedtls_mutex_init( &ctx->mutex );
#endif
}
/*
* Set padding for an existing RSA context
*/
void mbedtls_rsa_set_padding( mbedtls_rsa_context *ctx, int padding, int hash_id )
{
ctx->padding = padding;
ctx->hash_id = hash_id;
}
#if defined(MBEDTLS_GENPRIME)
/*
* Generate an RSA keypair
*/
int mbedtls_rsa_gen_key( mbedtls_rsa_context *ctx,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng,
unsigned int nbits, int exponent )
{
int ret;
mbedtls_mpi P1, Q1, H, G;
if( f_rng == NULL || nbits < 128 || exponent < 3 )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
mbedtls_mpi_init( &P1 ); mbedtls_mpi_init( &Q1 ); mbedtls_mpi_init( &H ); mbedtls_mpi_init( &G );
/*
* find primes P and Q with Q < P so that:
* GCD( E, (P-1)*(Q-1) ) == 1
*/
MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &ctx->E, exponent ) );
do
{
MBEDTLS_MPI_CHK( mbedtls_mpi_gen_prime( &ctx->P, ( nbits + 1 ) >> 1, 0,
f_rng, p_rng ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_gen_prime( &ctx->Q, ( nbits + 1 ) >> 1, 0,
f_rng, p_rng ) );
if( mbedtls_mpi_cmp_mpi( &ctx->P, &ctx->Q ) < 0 )
mbedtls_mpi_swap( &ctx->P, &ctx->Q );
if( mbedtls_mpi_cmp_mpi( &ctx->P, &ctx->Q ) == 0 )
continue;
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &ctx->N, &ctx->P, &ctx->Q ) );
if( mbedtls_mpi_bitlen( &ctx->N ) != nbits )
continue;
MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &P1, &ctx->P, 1 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &Q1, &ctx->Q, 1 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &H, &P1, &Q1 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_gcd( &G, &ctx->E, &H ) );
}
while( mbedtls_mpi_cmp_int( &G, 1 ) != 0 );
/*
* D = E^-1 mod ((P-1)*(Q-1))
* DP = D mod (P - 1)
* DQ = D mod (Q - 1)
* QP = Q^-1 mod P
*/
MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &ctx->D , &ctx->E, &H ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &ctx->DP, &ctx->D, &P1 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &ctx->DQ, &ctx->D, &Q1 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &ctx->QP, &ctx->Q, &ctx->P ) );
ctx->len = ( mbedtls_mpi_bitlen( &ctx->N ) + 7 ) >> 3;
cleanup:
mbedtls_mpi_free( &P1 ); mbedtls_mpi_free( &Q1 ); mbedtls_mpi_free( &H ); mbedtls_mpi_free( &G );
if( ret != 0 )
{
mbedtls_rsa_free( ctx );
return( MBEDTLS_ERR_RSA_KEY_GEN_FAILED + ret );
}
return( 0 );
}
#endif /* MBEDTLS_GENPRIME */
/*
* Check a public RSA key
*/
int mbedtls_rsa_check_pubkey( const mbedtls_rsa_context *ctx )
{
if( !ctx->N.p || !ctx->E.p )
return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
if( ( ctx->N.p[0] & 1 ) == 0 ||
( ctx->E.p[0] & 1 ) == 0 )
return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
if( mbedtls_mpi_bitlen( &ctx->N ) < 128 ||
mbedtls_mpi_bitlen( &ctx->N ) > MBEDTLS_MPI_MAX_BITS )
return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
if( mbedtls_mpi_bitlen( &ctx->E ) < 2 ||
mbedtls_mpi_cmp_mpi( &ctx->E, &ctx->N ) >= 0 )
return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
return( 0 );
}
/*
* Check a private RSA key
*/
int mbedtls_rsa_check_privkey( const mbedtls_rsa_context *ctx )
{
int ret;
mbedtls_mpi PQ, DE, P1, Q1, H, I, G, G2, L1, L2, DP, DQ, QP;
if( ( ret = mbedtls_rsa_check_pubkey( ctx ) ) != 0 )
return( ret );
if( !ctx->P.p || !ctx->Q.p || !ctx->D.p )
return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
mbedtls_mpi_init( &PQ ); mbedtls_mpi_init( &DE ); mbedtls_mpi_init( &P1 ); mbedtls_mpi_init( &Q1 );
mbedtls_mpi_init( &H ); mbedtls_mpi_init( &I ); mbedtls_mpi_init( &G ); mbedtls_mpi_init( &G2 );
mbedtls_mpi_init( &L1 ); mbedtls_mpi_init( &L2 ); mbedtls_mpi_init( &DP ); mbedtls_mpi_init( &DQ );
mbedtls_mpi_init( &QP );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &PQ, &ctx->P, &ctx->Q ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &DE, &ctx->D, &ctx->E ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &P1, &ctx->P, 1 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &Q1, &ctx->Q, 1 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &H, &P1, &Q1 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_gcd( &G, &ctx->E, &H ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_gcd( &G2, &P1, &Q1 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_div_mpi( &L1, &L2, &H, &G2 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &I, &DE, &L1 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &DP, &ctx->D, &P1 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &DQ, &ctx->D, &Q1 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &QP, &ctx->Q, &ctx->P ) );
/*
* Check for a valid PKCS1v2 private key
*/
if( mbedtls_mpi_cmp_mpi( &PQ, &ctx->N ) != 0 ||
mbedtls_mpi_cmp_mpi( &DP, &ctx->DP ) != 0 ||
mbedtls_mpi_cmp_mpi( &DQ, &ctx->DQ ) != 0 ||
mbedtls_mpi_cmp_mpi( &QP, &ctx->QP ) != 0 ||
mbedtls_mpi_cmp_int( &L2, 0 ) != 0 ||
mbedtls_mpi_cmp_int( &I, 1 ) != 0 ||
mbedtls_mpi_cmp_int( &G, 1 ) != 0 )
{
ret = MBEDTLS_ERR_RSA_KEY_CHECK_FAILED;
}
cleanup:
mbedtls_mpi_free( &PQ ); mbedtls_mpi_free( &DE ); mbedtls_mpi_free( &P1 ); mbedtls_mpi_free( &Q1 );
mbedtls_mpi_free( &H ); mbedtls_mpi_free( &I ); mbedtls_mpi_free( &G ); mbedtls_mpi_free( &G2 );
mbedtls_mpi_free( &L1 ); mbedtls_mpi_free( &L2 ); mbedtls_mpi_free( &DP ); mbedtls_mpi_free( &DQ );
mbedtls_mpi_free( &QP );
if( ret == MBEDTLS_ERR_RSA_KEY_CHECK_FAILED )
return( ret );
if( ret != 0 )
return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED + ret );
return( 0 );
}
/*
* Check if contexts holding a public and private key match
*/
int mbedtls_rsa_check_pub_priv( const mbedtls_rsa_context *pub, const mbedtls_rsa_context *prv )
{
if( mbedtls_rsa_check_pubkey( pub ) != 0 ||
mbedtls_rsa_check_privkey( prv ) != 0 )
{
return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
}
if( mbedtls_mpi_cmp_mpi( &pub->N, &prv->N ) != 0 ||
mbedtls_mpi_cmp_mpi( &pub->E, &prv->E ) != 0 )
{
return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
}
return( 0 );
}
/*
* Do an RSA public key operation
*/
int mbedtls_rsa_public( mbedtls_rsa_context *ctx,
const unsigned char *input,
unsigned char *output )
{
int ret;
size_t olen;
mbedtls_mpi T;
mbedtls_mpi_init( &T );
#if defined(MBEDTLS_THREADING_C)
if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
return( ret );
#endif
MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &T, input, ctx->len ) );
if( mbedtls_mpi_cmp_mpi( &T, &ctx->N ) >= 0 )
{
ret = MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
goto cleanup;
}
olen = ctx->len;
MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &T, &T, &ctx->E, &ctx->N, &ctx->RN ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &T, output, olen ) );
cleanup:
#if defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif
mbedtls_mpi_free( &T );
if( ret != 0 )
return( MBEDTLS_ERR_RSA_PUBLIC_FAILED + ret );
return( 0 );
}
/*
* Generate or update blinding values, see section 10 of:
* KOCHER, Paul C. Timing attacks on implementations of Diffie-Hellman, RSA,
* DSS, and other systems. In : Advances in Cryptology-CRYPTO'96. Springer
* Berlin Heidelberg, 1996. p. 104-113.
*/
static int rsa_prepare_blinding( mbedtls_rsa_context *ctx,
int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
{
int ret, count = 0;
if( ctx->Vf.p != NULL )
{
/* We already have blinding values, just update them by squaring */
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &ctx->Vi, &ctx->Vi, &ctx->Vi ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &ctx->Vi, &ctx->Vi, &ctx->N ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &ctx->Vf, &ctx->Vf, &ctx->Vf ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &ctx->Vf, &ctx->Vf, &ctx->N ) );
goto cleanup;
}
/* Unblinding value: Vf = random number, invertible mod N */
do {
if( count++ > 10 )
return( MBEDTLS_ERR_RSA_RNG_FAILED );
MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( &ctx->Vf, ctx->len - 1, f_rng, p_rng ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_gcd( &ctx->Vi, &ctx->Vf, &ctx->N ) );
} while( mbedtls_mpi_cmp_int( &ctx->Vi, 1 ) != 0 );
/* Blinding value: Vi = Vf^(-e) mod N */
MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &ctx->Vi, &ctx->Vf, &ctx->N ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &ctx->Vi, &ctx->Vi, &ctx->E, &ctx->N, &ctx->RN ) );
cleanup:
return( ret );
}
/*
* Do an RSA private key operation
*/
int mbedtls_rsa_private( mbedtls_rsa_context *ctx,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng,
const unsigned char *input,
unsigned char *output )
{
int ret;
size_t olen;
mbedtls_mpi T, T1, T2;
mbedtls_mpi_init( &T ); mbedtls_mpi_init( &T1 ); mbedtls_mpi_init( &T2 );
#if defined(MBEDTLS_THREADING_C)
if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
return( ret );
#endif
MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &T, input, ctx->len ) );
if( mbedtls_mpi_cmp_mpi( &T, &ctx->N ) >= 0 )
{
ret = MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
goto cleanup;
}
if( f_rng != NULL )
{
/*
* Blinding
* T = T * Vi mod N
*/
MBEDTLS_MPI_CHK( rsa_prepare_blinding( ctx, f_rng, p_rng ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &T, &T, &ctx->Vi ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &T, &T, &ctx->N ) );
}
#if defined(MBEDTLS_RSA_NO_CRT)
MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &T, &T, &ctx->D, &ctx->N, &ctx->RN ) );
#else
/*
* faster decryption using the CRT
*
* T1 = input ^ dP mod P
* T2 = input ^ dQ mod Q
*/
MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &T1, &T, &ctx->DP, &ctx->P, &ctx->RP ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &T2, &T, &ctx->DQ, &ctx->Q, &ctx->RQ ) );
/*
* T = (T1 - T2) * (Q^-1 mod P) mod P
*/
MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &T, &T1, &T2 ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &T1, &T, &ctx->QP ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &T, &T1, &ctx->P ) );
/*
* T = T2 + T * Q
*/
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &T1, &T, &ctx->Q ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( &T, &T2, &T1 ) );
#endif /* MBEDTLS_RSA_NO_CRT */
if( f_rng != NULL )
{
/*
* Unblind
* T = T * Vf mod N
*/
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &T, &T, &ctx->Vf ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &T, &T, &ctx->N ) );
}
olen = ctx->len;
MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &T, output, olen ) );
cleanup:
#if defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif
mbedtls_mpi_free( &T ); mbedtls_mpi_free( &T1 ); mbedtls_mpi_free( &T2 );
if( ret != 0 )
return( MBEDTLS_ERR_RSA_PRIVATE_FAILED + ret );
return( 0 );
}
#if defined(MBEDTLS_PKCS1_V21)
/**
* Generate and apply the MGF1 operation (from PKCS#1 v2.1) to a buffer.
*
* \param dst buffer to mask
* \param dlen length of destination buffer
* \param src source of the mask generation
* \param slen length of the source buffer
* \param md_ctx message digest context to use
*/
static void mgf_mask( unsigned char *dst, size_t dlen, unsigned char *src,
size_t slen, mbedtls_md_context_t *md_ctx )
{
unsigned char mask[MBEDTLS_MD_MAX_SIZE];
unsigned char counter[4];
unsigned char *p;
unsigned int hlen;
size_t i, use_len;
memset( mask, 0, MBEDTLS_MD_MAX_SIZE );
memset( counter, 0, 4 );
hlen = mbedtls_md_get_size( md_ctx->md_info );
// Generate and apply dbMask
//
p = dst;
while( dlen > 0 )
{
use_len = hlen;
if( dlen < hlen )
use_len = dlen;
mbedtls_md_starts( md_ctx );
mbedtls_md_update( md_ctx, src, slen );
mbedtls_md_update( md_ctx, counter, 4 );
mbedtls_md_finish( md_ctx, mask );
for( i = 0; i < use_len; ++i )
*p++ ^= mask[i];
counter[3]++;
dlen -= use_len;
}
}
#endif /* MBEDTLS_PKCS1_V21 */
#if defined(MBEDTLS_PKCS1_V21)
/*
* Implementation of the PKCS#1 v2.1 RSAES-OAEP-ENCRYPT function
*/
int mbedtls_rsa_rsaes_oaep_encrypt( mbedtls_rsa_context *ctx,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng,
int mode,
const unsigned char *label, size_t label_len,
size_t ilen,
const unsigned char *input,
unsigned char *output )
{
size_t olen;
int ret;
unsigned char *p = output;
unsigned int hlen;
const mbedtls_md_info_t *md_info;
mbedtls_md_context_t md_ctx;
if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V21 )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
if( f_rng == NULL )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
md_info = mbedtls_md_info_from_type( (mbedtls_md_type_t) ctx->hash_id );
if( md_info == NULL )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
olen = ctx->len;
hlen = mbedtls_md_get_size( md_info );
if( olen < ilen + 2 * hlen + 2 )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
memset( output, 0, olen );
*p++ = 0;
// Generate a random octet string seed
//
if( ( ret = f_rng( p_rng, p, hlen ) ) != 0 )
return( MBEDTLS_ERR_RSA_RNG_FAILED + ret );
p += hlen;
// Construct DB
//
mbedtls_md( md_info, label, label_len, p );
p += hlen;
p += olen - 2 * hlen - 2 - ilen;
*p++ = 1;
memcpy( p, input, ilen );
mbedtls_md_init( &md_ctx );
mbedtls_md_setup( &md_ctx, md_info, 0 );
// maskedDB: Apply dbMask to DB
//
mgf_mask( output + hlen + 1, olen - hlen - 1, output + 1, hlen,
&md_ctx );
// maskedSeed: Apply seedMask to seed
//
mgf_mask( output + 1, hlen, output + hlen + 1, olen - hlen - 1,
&md_ctx );
mbedtls_md_free( &md_ctx );
return( ( mode == MBEDTLS_RSA_PUBLIC )
? mbedtls_rsa_public( ctx, output, output )
: mbedtls_rsa_private( ctx, f_rng, p_rng, output, output ) );
}
#endif /* MBEDTLS_PKCS1_V21 */
#if defined(MBEDTLS_PKCS1_V15)
/*
* Implementation of the PKCS#1 v2.1 RSAES-PKCS1-V1_5-ENCRYPT function
*/
int mbedtls_rsa_rsaes_pkcs1_v15_encrypt( mbedtls_rsa_context *ctx,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng,
int mode, size_t ilen,
const unsigned char *input,
unsigned char *output )
{
size_t nb_pad, olen;
int ret;
unsigned char *p = output;
if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V15 )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
if( f_rng == NULL )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
olen = ctx->len;
if( olen < ilen + 11 )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
nb_pad = olen - 3 - ilen;
*p++ = 0;
if( mode == MBEDTLS_RSA_PUBLIC )
{
*p++ = MBEDTLS_RSA_CRYPT;
while( nb_pad-- > 0 )
{
int rng_dl = 100;
do {
ret = f_rng( p_rng, p, 1 );
} while( *p == 0 && --rng_dl && ret == 0 );
// Check if RNG failed to generate data
//
if( rng_dl == 0 || ret != 0 )
return( MBEDTLS_ERR_RSA_RNG_FAILED + ret );
p++;
}
}
else
{
*p++ = MBEDTLS_RSA_SIGN;
while( nb_pad-- > 0 )
*p++ = 0xFF;
}
*p++ = 0;
memcpy( p, input, ilen );
return( ( mode == MBEDTLS_RSA_PUBLIC )
? mbedtls_rsa_public( ctx, output, output )
: mbedtls_rsa_private( ctx, f_rng, p_rng, output, output ) );
}
#endif /* MBEDTLS_PKCS1_V15 */
/*
* Add the message padding, then do an RSA operation
*/
int mbedtls_rsa_pkcs1_encrypt( mbedtls_rsa_context *ctx,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng,
int mode, size_t ilen,
const unsigned char *input,
unsigned char *output )
{
switch( ctx->padding )
{
#if defined(MBEDTLS_PKCS1_V15)
case MBEDTLS_RSA_PKCS_V15:
return mbedtls_rsa_rsaes_pkcs1_v15_encrypt( ctx, f_rng, p_rng, mode, ilen,
input, output );
#endif
#if defined(MBEDTLS_PKCS1_V21)
case MBEDTLS_RSA_PKCS_V21:
return mbedtls_rsa_rsaes_oaep_encrypt( ctx, f_rng, p_rng, mode, NULL, 0,
ilen, input, output );
#endif
default:
return( MBEDTLS_ERR_RSA_INVALID_PADDING );
}
}
#if defined(MBEDTLS_PKCS1_V21)
/*
* Implementation of the PKCS#1 v2.1 RSAES-OAEP-DECRYPT function
*/
int mbedtls_rsa_rsaes_oaep_decrypt( mbedtls_rsa_context *ctx,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng,
int mode,
const unsigned char *label, size_t label_len,
size_t *olen,
const unsigned char *input,
unsigned char *output,
size_t output_max_len )
{
int ret;
size_t ilen, i, pad_len;
unsigned char *p, bad, pad_done;
unsigned char buf[MBEDTLS_MPI_MAX_SIZE];
unsigned char lhash[MBEDTLS_MD_MAX_SIZE];
unsigned int hlen;
const mbedtls_md_info_t *md_info;
mbedtls_md_context_t md_ctx;
/*
* Parameters sanity checks
*/
if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V21 )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
ilen = ctx->len;
if( ilen < 16 || ilen > sizeof( buf ) )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
md_info = mbedtls_md_info_from_type( (mbedtls_md_type_t) ctx->hash_id );
if( md_info == NULL )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
/*
* RSA operation
*/
ret = ( mode == MBEDTLS_RSA_PUBLIC )
? mbedtls_rsa_public( ctx, input, buf )
: mbedtls_rsa_private( ctx, f_rng, p_rng, input, buf );
if( ret != 0 )
return( ret );
/*
* Unmask data and generate lHash
*/
hlen = mbedtls_md_get_size( md_info );
mbedtls_md_init( &md_ctx );
mbedtls_md_setup( &md_ctx, md_info, 0 );
/* Generate lHash */
mbedtls_md( md_info, label, label_len, lhash );
/* seed: Apply seedMask to maskedSeed */
mgf_mask( buf + 1, hlen, buf + hlen + 1, ilen - hlen - 1,
&md_ctx );
/* DB: Apply dbMask to maskedDB */
mgf_mask( buf + hlen + 1, ilen - hlen - 1, buf + 1, hlen,
&md_ctx );
mbedtls_md_free( &md_ctx );
/*
* Check contents, in "constant-time"
*/
p = buf;
bad = 0;
bad |= *p++; /* First byte must be 0 */
p += hlen; /* Skip seed */
/* Check lHash */
for( i = 0; i < hlen; i++ )
bad |= lhash[i] ^ *p++;
/* Get zero-padding len, but always read till end of buffer
* (minus one, for the 01 byte) */
pad_len = 0;
pad_done = 0;
for( i = 0; i < ilen - 2 * hlen - 2; i++ )
{
pad_done |= p[i];
pad_len += ((pad_done | (unsigned char)-pad_done) >> 7) ^ 1;
}
p += pad_len;
bad |= *p++ ^ 0x01;
/*
* The only information "leaked" is whether the padding was correct or not
* (eg, no data is copied if it was not correct). This meets the
* recommendations in PKCS#1 v2.2: an opponent cannot distinguish between
* the different error conditions.
*/
if( bad != 0 )
return( MBEDTLS_ERR_RSA_INVALID_PADDING );
if( ilen - ( p - buf ) > output_max_len )
return( MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE );
*olen = ilen - (p - buf);
memcpy( output, p, *olen );
return( 0 );
}
#endif /* MBEDTLS_PKCS1_V21 */
#if defined(MBEDTLS_PKCS1_V15)
/*
* Implementation of the PKCS#1 v2.1 RSAES-PKCS1-V1_5-DECRYPT function
*/
int mbedtls_rsa_rsaes_pkcs1_v15_decrypt( mbedtls_rsa_context *ctx,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng,
int mode, size_t *olen,
const unsigned char *input,
unsigned char *output,
size_t output_max_len)
{
int ret;
size_t ilen, pad_count = 0, i;
unsigned char *p, bad, pad_done = 0;
unsigned char buf[MBEDTLS_MPI_MAX_SIZE];
if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V15 )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
ilen = ctx->len;
if( ilen < 16 || ilen > sizeof( buf ) )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
ret = ( mode == MBEDTLS_RSA_PUBLIC )
? mbedtls_rsa_public( ctx, input, buf )
: mbedtls_rsa_private( ctx, f_rng, p_rng, input, buf );
if( ret != 0 )
return( ret );
p = buf;
bad = 0;
/*
* Check and get padding len in "constant-time"
*/
bad |= *p++; /* First byte must be 0 */
/* This test does not depend on secret data */
if( mode == MBEDTLS_RSA_PRIVATE )
{
bad |= *p++ ^ MBEDTLS_RSA_CRYPT;
/* Get padding len, but always read till end of buffer
* (minus one, for the 00 byte) */
for( i = 0; i < ilen - 3; i++ )
{
pad_done |= ((p[i] | (unsigned char)-p[i]) >> 7) ^ 1;
pad_count += ((pad_done | (unsigned char)-pad_done) >> 7) ^ 1;
}
p += pad_count;
bad |= *p++; /* Must be zero */
}
else
{
bad |= *p++ ^ MBEDTLS_RSA_SIGN;
/* Get padding len, but always read till end of buffer
* (minus one, for the 00 byte) */
for( i = 0; i < ilen - 3; i++ )
{
pad_done |= ( p[i] != 0xFF );
pad_count += ( pad_done == 0 );
}
p += pad_count;
bad |= *p++; /* Must be zero */
}
if( bad )
return( MBEDTLS_ERR_RSA_INVALID_PADDING );
if( ilen - ( p - buf ) > output_max_len )
return( MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE );
*olen = ilen - (p - buf);
memcpy( output, p, *olen );
return( 0 );
}
#endif /* MBEDTLS_PKCS1_V15 */
/*
* Do an RSA operation, then remove the message padding
*/
int mbedtls_rsa_pkcs1_decrypt( mbedtls_rsa_context *ctx,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng,
int mode, size_t *olen,
const unsigned char *input,
unsigned char *output,
size_t output_max_len)
{
switch( ctx->padding )
{
#if defined(MBEDTLS_PKCS1_V15)
case MBEDTLS_RSA_PKCS_V15:
return mbedtls_rsa_rsaes_pkcs1_v15_decrypt( ctx, f_rng, p_rng, mode, olen,
input, output, output_max_len );
#endif
#if defined(MBEDTLS_PKCS1_V21)
case MBEDTLS_RSA_PKCS_V21:
return mbedtls_rsa_rsaes_oaep_decrypt( ctx, f_rng, p_rng, mode, NULL, 0,
olen, input, output,
output_max_len );
#endif
default:
return( MBEDTLS_ERR_RSA_INVALID_PADDING );
}
}
#if defined(MBEDTLS_PKCS1_V21)
/*
* Implementation of the PKCS#1 v2.1 RSASSA-PSS-SIGN function
*/
int mbedtls_rsa_rsassa_pss_sign( mbedtls_rsa_context *ctx,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng,
int mode,
mbedtls_md_type_t md_alg,
unsigned int hashlen,
const unsigned char *hash,
unsigned char *sig )
{
size_t olen;
unsigned char *p = sig;
unsigned char salt[MBEDTLS_MD_MAX_SIZE];
unsigned int slen, hlen, offset = 0;
int ret;
size_t msb;
const mbedtls_md_info_t *md_info;
mbedtls_md_context_t md_ctx;
if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V21 )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
if( f_rng == NULL )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
olen = ctx->len;
if( md_alg != MBEDTLS_MD_NONE )
{
// Gather length of hash to sign
//
md_info = mbedtls_md_info_from_type( md_alg );
if( md_info == NULL )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
hashlen = mbedtls_md_get_size( md_info );
}
md_info = mbedtls_md_info_from_type( (mbedtls_md_type_t) ctx->hash_id );
if( md_info == NULL )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
hlen = mbedtls_md_get_size( md_info );
slen = hlen;
if( olen < hlen + slen + 2 )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
memset( sig, 0, olen );
// Generate salt of length slen
//
if( ( ret = f_rng( p_rng, salt, slen ) ) != 0 )
return( MBEDTLS_ERR_RSA_RNG_FAILED + ret );
// Note: EMSA-PSS encoding is over the length of N - 1 bits
//
msb = mbedtls_mpi_bitlen( &ctx->N ) - 1;
p += olen - hlen * 2 - 2;
*p++ = 0x01;
memcpy( p, salt, slen );
p += slen;
mbedtls_md_init( &md_ctx );
mbedtls_md_setup( &md_ctx, md_info, 0 );
// Generate H = Hash( M' )
//
mbedtls_md_starts( &md_ctx );
mbedtls_md_update( &md_ctx, p, 8 );
mbedtls_md_update( &md_ctx, hash, hashlen );
mbedtls_md_update( &md_ctx, salt, slen );
mbedtls_md_finish( &md_ctx, p );
// Compensate for boundary condition when applying mask
//
if( msb % 8 == 0 )
offset = 1;
// maskedDB: Apply dbMask to DB
//
mgf_mask( sig + offset, olen - hlen - 1 - offset, p, hlen, &md_ctx );
mbedtls_md_free( &md_ctx );
msb = mbedtls_mpi_bitlen( &ctx->N ) - 1;
sig[0] &= 0xFF >> ( olen * 8 - msb );
p += hlen;
*p++ = 0xBC;
return( ( mode == MBEDTLS_RSA_PUBLIC )
? mbedtls_rsa_public( ctx, sig, sig )
: mbedtls_rsa_private( ctx, f_rng, p_rng, sig, sig ) );
}
#endif /* MBEDTLS_PKCS1_V21 */
#if defined(MBEDTLS_PKCS1_V15)
/*
* Implementation of the PKCS#1 v2.1 RSASSA-PKCS1-V1_5-SIGN function
*/
/*
* Do an RSA operation to sign the message digest
*/
int mbedtls_rsa_rsassa_pkcs1_v15_sign( mbedtls_rsa_context *ctx,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng,
int mode,
mbedtls_md_type_t md_alg,
unsigned int hashlen,
const unsigned char *hash,
unsigned char *sig )
{
size_t nb_pad, olen, oid_size = 0;
unsigned char *p = sig;
const char *oid = NULL;
unsigned char *sig_try = NULL, *verif = NULL;
size_t i;
unsigned char diff;
volatile unsigned char diff_no_optimize;
int ret;
if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V15 )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
olen = ctx->len;
nb_pad = olen - 3;
if( md_alg != MBEDTLS_MD_NONE )
{
const mbedtls_md_info_t *md_info = mbedtls_md_info_from_type( md_alg );
if( md_info == NULL )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
if( mbedtls_oid_get_oid_by_md( md_alg, &oid, &oid_size ) != 0 )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
nb_pad -= 10 + oid_size;
hashlen = mbedtls_md_get_size( md_info );
}
nb_pad -= hashlen;
if( ( nb_pad < 8 ) || ( nb_pad > olen ) )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
*p++ = 0;
*p++ = MBEDTLS_RSA_SIGN;
memset( p, 0xFF, nb_pad );
p += nb_pad;
*p++ = 0;
if( md_alg == MBEDTLS_MD_NONE )
{
memcpy( p, hash, hashlen );
}
else
{
/*
* DigestInfo ::= SEQUENCE {
* digestAlgorithm DigestAlgorithmIdentifier,
* digest Digest }
*
* DigestAlgorithmIdentifier ::= AlgorithmIdentifier
*
* Digest ::= OCTET STRING
*/
*p++ = MBEDTLS_ASN1_SEQUENCE | MBEDTLS_ASN1_CONSTRUCTED;
*p++ = (unsigned char) ( 0x08 + oid_size + hashlen );
*p++ = MBEDTLS_ASN1_SEQUENCE | MBEDTLS_ASN1_CONSTRUCTED;
*p++ = (unsigned char) ( 0x04 + oid_size );
*p++ = MBEDTLS_ASN1_OID;
*p++ = oid_size & 0xFF;
memcpy( p, oid, oid_size );
p += oid_size;
*p++ = MBEDTLS_ASN1_NULL;
*p++ = 0x00;
*p++ = MBEDTLS_ASN1_OCTET_STRING;
*p++ = hashlen;
memcpy( p, hash, hashlen );
}
if( mode == MBEDTLS_RSA_PUBLIC )
return( mbedtls_rsa_public( ctx, sig, sig ) );
/*
* In order to prevent Lenstra's attack, make the signature in a
* temporary buffer and check it before returning it.
*/
sig_try = mbedtls_calloc( 1, ctx->len );
verif = mbedtls_calloc( 1, ctx->len );
if( sig_try == NULL || verif == NULL )
return( MBEDTLS_ERR_MPI_ALLOC_FAILED );
MBEDTLS_MPI_CHK( mbedtls_rsa_private( ctx, f_rng, p_rng, sig, sig_try ) );
MBEDTLS_MPI_CHK( mbedtls_rsa_public( ctx, sig_try, verif ) );
/* Compare in constant time just in case */
for( diff = 0, i = 0; i < ctx->len; i++ )
diff |= verif[i] ^ sig[i];
diff_no_optimize = diff;
if( diff_no_optimize != 0 )
{
ret = MBEDTLS_ERR_RSA_PRIVATE_FAILED;
goto cleanup;
}
memcpy( sig, sig_try, ctx->len );
cleanup:
mbedtls_free( sig_try );
mbedtls_free( verif );
return( ret );
}
#endif /* MBEDTLS_PKCS1_V15 */
/*
* Do an RSA operation to sign the message digest
*/
int mbedtls_rsa_pkcs1_sign( mbedtls_rsa_context *ctx,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng,
int mode,
mbedtls_md_type_t md_alg,
unsigned int hashlen,
const unsigned char *hash,
unsigned char *sig )
{
switch( ctx->padding )
{
#if defined(MBEDTLS_PKCS1_V15)
case MBEDTLS_RSA_PKCS_V15:
return mbedtls_rsa_rsassa_pkcs1_v15_sign( ctx, f_rng, p_rng, mode, md_alg,
hashlen, hash, sig );
#endif
#if defined(MBEDTLS_PKCS1_V21)
case MBEDTLS_RSA_PKCS_V21:
return mbedtls_rsa_rsassa_pss_sign( ctx, f_rng, p_rng, mode, md_alg,
hashlen, hash, sig );
#endif
default:
return( MBEDTLS_ERR_RSA_INVALID_PADDING );
}
}
#if defined(MBEDTLS_PKCS1_V21)
/*
* Implementation of the PKCS#1 v2.1 RSASSA-PSS-VERIFY function
*/
int mbedtls_rsa_rsassa_pss_verify_ext( mbedtls_rsa_context *ctx,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng,
int mode,
mbedtls_md_type_t md_alg,
unsigned int hashlen,
const unsigned char *hash,
mbedtls_md_type_t mgf1_hash_id,
int expected_salt_len,
const unsigned char *sig )
{
int ret;
size_t siglen;
unsigned char *p;
unsigned char buf[MBEDTLS_MPI_MAX_SIZE];
unsigned char result[MBEDTLS_MD_MAX_SIZE];
unsigned char zeros[8];
unsigned int hlen;
size_t slen, msb;
const mbedtls_md_info_t *md_info;
mbedtls_md_context_t md_ctx;
if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V21 )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
siglen = ctx->len;
if( siglen < 16 || siglen > sizeof( buf ) )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
ret = ( mode == MBEDTLS_RSA_PUBLIC )
? mbedtls_rsa_public( ctx, sig, buf )
: mbedtls_rsa_private( ctx, f_rng, p_rng, sig, buf );
if( ret != 0 )
return( ret );
p = buf;
if( buf[siglen - 1] != 0xBC )
return( MBEDTLS_ERR_RSA_INVALID_PADDING );
if( md_alg != MBEDTLS_MD_NONE )
{
// Gather length of hash to sign
//
md_info = mbedtls_md_info_from_type( md_alg );
if( md_info == NULL )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
hashlen = mbedtls_md_get_size( md_info );
}
md_info = mbedtls_md_info_from_type( mgf1_hash_id );
if( md_info == NULL )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
hlen = mbedtls_md_get_size( md_info );
slen = siglen - hlen - 1; /* Currently length of salt + padding */
memset( zeros, 0, 8 );
// Note: EMSA-PSS verification is over the length of N - 1 bits
//
msb = mbedtls_mpi_bitlen( &ctx->N ) - 1;
// Compensate for boundary condition when applying mask
//
if( msb % 8 == 0 )
{
p++;
siglen -= 1;
}
if( buf[0] >> ( 8 - siglen * 8 + msb ) )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
mbedtls_md_init( &md_ctx );
mbedtls_md_setup( &md_ctx, md_info, 0 );
mgf_mask( p, siglen - hlen - 1, p + siglen - hlen - 1, hlen, &md_ctx );
buf[0] &= 0xFF >> ( siglen * 8 - msb );
while( p < buf + siglen && *p == 0 )
p++;
if( p == buf + siglen ||
*p++ != 0x01 )
{
mbedtls_md_free( &md_ctx );
return( MBEDTLS_ERR_RSA_INVALID_PADDING );
}
/* Actual salt len */
slen -= p - buf;
if( expected_salt_len != MBEDTLS_RSA_SALT_LEN_ANY &&
slen != (size_t) expected_salt_len )
{
mbedtls_md_free( &md_ctx );
return( MBEDTLS_ERR_RSA_INVALID_PADDING );
}
// Generate H = Hash( M' )
//
mbedtls_md_starts( &md_ctx );
mbedtls_md_update( &md_ctx, zeros, 8 );
mbedtls_md_update( &md_ctx, hash, hashlen );
mbedtls_md_update( &md_ctx, p, slen );
mbedtls_md_finish( &md_ctx, result );
mbedtls_md_free( &md_ctx );
if( memcmp( p + slen, result, hlen ) == 0 )
return( 0 );
else
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
}
/*
* Simplified PKCS#1 v2.1 RSASSA-PSS-VERIFY function
*/
int mbedtls_rsa_rsassa_pss_verify( mbedtls_rsa_context *ctx,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng,
int mode,
mbedtls_md_type_t md_alg,
unsigned int hashlen,
const unsigned char *hash,
const unsigned char *sig )
{
mbedtls_md_type_t mgf1_hash_id = ( ctx->hash_id != MBEDTLS_MD_NONE )
? (mbedtls_md_type_t) ctx->hash_id
: md_alg;
return( mbedtls_rsa_rsassa_pss_verify_ext( ctx, f_rng, p_rng, mode,
md_alg, hashlen, hash,
mgf1_hash_id, MBEDTLS_RSA_SALT_LEN_ANY,
sig ) );
}
#endif /* MBEDTLS_PKCS1_V21 */
#if defined(MBEDTLS_PKCS1_V15)
/*
* Implementation of the PKCS#1 v2.1 RSASSA-PKCS1-v1_5-VERIFY function
*/
int mbedtls_rsa_rsassa_pkcs1_v15_verify( mbedtls_rsa_context *ctx,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng,
int mode,
mbedtls_md_type_t md_alg,
unsigned int hashlen,
const unsigned char *hash,
const unsigned char *sig )
{
int ret;
size_t len, siglen, asn1_len;
unsigned char *p, *end;
unsigned char buf[MBEDTLS_MPI_MAX_SIZE];
mbedtls_md_type_t msg_md_alg;
const mbedtls_md_info_t *md_info;
mbedtls_asn1_buf oid;
if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V15 )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
siglen = ctx->len;
if( siglen < 16 || siglen > sizeof( buf ) )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
ret = ( mode == MBEDTLS_RSA_PUBLIC )
? mbedtls_rsa_public( ctx, sig, buf )
: mbedtls_rsa_private( ctx, f_rng, p_rng, sig, buf );
if( ret != 0 )
return( ret );
p = buf;
if( *p++ != 0 || *p++ != MBEDTLS_RSA_SIGN )
return( MBEDTLS_ERR_RSA_INVALID_PADDING );
while( *p != 0 )
{
if( p >= buf + siglen - 1 || *p != 0xFF )
return( MBEDTLS_ERR_RSA_INVALID_PADDING );
p++;
}
p++;
len = siglen - ( p - buf );
if( len == hashlen && md_alg == MBEDTLS_MD_NONE )
{
if( memcmp( p, hash, hashlen ) == 0 )
return( 0 );
else
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
}
md_info = mbedtls_md_info_from_type( md_alg );
if( md_info == NULL )
return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
hashlen = mbedtls_md_get_size( md_info );
end = p + len;
// Parse the ASN.1 structure inside the PKCS#1 v1.5 structure
//
if( ( ret = mbedtls_asn1_get_tag( &p, end, &asn1_len,
MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
if( asn1_len + 2 != len )
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
if( ( ret = mbedtls_asn1_get_tag( &p, end, &asn1_len,
MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
if( asn1_len + 6 + hashlen != len )
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
if( ( ret = mbedtls_asn1_get_tag( &p, end, &oid.len, MBEDTLS_ASN1_OID ) ) != 0 )
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
oid.p = p;
p += oid.len;
if( mbedtls_oid_get_md_alg( &oid, &msg_md_alg ) != 0 )
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
if( md_alg != msg_md_alg )
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
/*
* assume the algorithm parameters must be NULL
*/
if( ( ret = mbedtls_asn1_get_tag( &p, end, &asn1_len, MBEDTLS_ASN1_NULL ) ) != 0 )
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
if( ( ret = mbedtls_asn1_get_tag( &p, end, &asn1_len, MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
if( asn1_len != hashlen )
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
if( memcmp( p, hash, hashlen ) != 0 )
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
p += hashlen;
if( p != end )
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
return( 0 );
}
#endif /* MBEDTLS_PKCS1_V15 */
/*
* Do an RSA operation and check the message digest
*/
int mbedtls_rsa_pkcs1_verify( mbedtls_rsa_context *ctx,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng,
int mode,
mbedtls_md_type_t md_alg,
unsigned int hashlen,
const unsigned char *hash,
const unsigned char *sig )
{
switch( ctx->padding )
{
#if defined(MBEDTLS_PKCS1_V15)
case MBEDTLS_RSA_PKCS_V15:
return mbedtls_rsa_rsassa_pkcs1_v15_verify( ctx, f_rng, p_rng, mode, md_alg,
hashlen, hash, sig );
#endif
#if defined(MBEDTLS_PKCS1_V21)
case MBEDTLS_RSA_PKCS_V21:
return mbedtls_rsa_rsassa_pss_verify( ctx, f_rng, p_rng, mode, md_alg,
hashlen, hash, sig );
#endif
default:
return( MBEDTLS_ERR_RSA_INVALID_PADDING );
}
}
/*
* Copy the components of an RSA key
*/
int mbedtls_rsa_copy( mbedtls_rsa_context *dst, const mbedtls_rsa_context *src )
{
int ret;
dst->ver = src->ver;
dst->len = src->len;
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->N, &src->N ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->E, &src->E ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->D, &src->D ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->P, &src->P ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->Q, &src->Q ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->DP, &src->DP ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->DQ, &src->DQ ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->QP, &src->QP ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->RN, &src->RN ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->RP, &src->RP ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->RQ, &src->RQ ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->Vi, &src->Vi ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->Vf, &src->Vf ) );
dst->padding = src->padding;
dst->hash_id = src->hash_id;
cleanup:
if( ret != 0 )
mbedtls_rsa_free( dst );
return( ret );
}
/*
* Free the components of an RSA key
*/
void mbedtls_rsa_free( mbedtls_rsa_context *ctx )
{
mbedtls_mpi_free( &ctx->Vi ); mbedtls_mpi_free( &ctx->Vf );
mbedtls_mpi_free( &ctx->RQ ); mbedtls_mpi_free( &ctx->RP ); mbedtls_mpi_free( &ctx->RN );
mbedtls_mpi_free( &ctx->QP ); mbedtls_mpi_free( &ctx->DQ ); mbedtls_mpi_free( &ctx->DP );
mbedtls_mpi_free( &ctx->Q ); mbedtls_mpi_free( &ctx->P ); mbedtls_mpi_free( &ctx->D );
mbedtls_mpi_free( &ctx->E ); mbedtls_mpi_free( &ctx->N );
#if defined(MBEDTLS_THREADING_C)
mbedtls_mutex_free( &ctx->mutex );
#endif
}
#if defined(MBEDTLS_SELF_TEST)
#include "mbedtls/sha1.h"
/*
* Example RSA-1024 keypair, for test purposes
*/
#define KEY_LEN 128
#define RSA_N "9292758453063D803DD603D5E777D788" \
"8ED1D5BF35786190FA2F23EBC0848AEA" \
"DDA92CA6C3D80B32C4D109BE0F36D6AE" \
"7130B9CED7ACDF54CFC7555AC14EEBAB" \
"93A89813FBF3C4F8066D2D800F7C38A8" \
"1AE31942917403FF4946B0A83D3D3E05" \
"EE57C6F5F5606FB5D4BC6CD34EE0801A" \
"5E94BB77B07507233A0BC7BAC8F90F79"
#define RSA_E "10001"
#define RSA_D "24BF6185468786FDD303083D25E64EFC" \
"66CA472BC44D253102F8B4A9D3BFA750" \
"91386C0077937FE33FA3252D28855837" \
"AE1B484A8A9A45F7EE8C0C634F99E8CD" \
"DF79C5CE07EE72C7F123142198164234" \
"CABB724CF78B8173B9F880FC86322407" \
"AF1FEDFDDE2BEB674CA15F3E81A1521E" \
"071513A1E85B5DFA031F21ECAE91A34D"
#define RSA_P "C36D0EB7FCD285223CFB5AABA5BDA3D8" \
"2C01CAD19EA484A87EA4377637E75500" \
"FCB2005C5C7DD6EC4AC023CDA285D796" \
"C3D9E75E1EFC42488BB4F1D13AC30A57"
#define RSA_Q "C000DF51A7C77AE8D7C7370C1FF55B69" \
"E211C2B9E5DB1ED0BF61D0D9899620F4" \
"910E4168387E3C30AA1E00C339A79508" \
"8452DD96A9A5EA5D9DCA68DA636032AF"
#define RSA_DP "C1ACF567564274FB07A0BBAD5D26E298" \
"3C94D22288ACD763FD8E5600ED4A702D" \
"F84198A5F06C2E72236AE490C93F07F8" \
"3CC559CD27BC2D1CA488811730BB5725"
#define RSA_DQ "4959CBF6F8FEF750AEE6977C155579C7" \
"D8AAEA56749EA28623272E4F7D0592AF" \
"7C1F1313CAC9471B5C523BFE592F517B" \
"407A1BD76C164B93DA2D32A383E58357"
#define RSA_QP "9AE7FBC99546432DF71896FC239EADAE" \
"F38D18D2B2F0E2DD275AA977E2BF4411" \
"F5A3B2A5D33605AEBBCCBA7FEB9F2D2F" \
"A74206CEC169D74BF5A8C50D6F48EA08"
#define PT_LEN 24
#define RSA_PT "\xAA\xBB\xCC\x03\x02\x01\x00\xFF\xFF\xFF\xFF\xFF" \
"\x11\x22\x33\x0A\x0B\x0C\xCC\xDD\xDD\xDD\xDD\xDD"
#if defined(MBEDTLS_PKCS1_V15)
static int myrand( void *rng_state, unsigned char *output, size_t len )
{
#if !defined(__OpenBSD__)
size_t i;
if( rng_state != NULL )
rng_state = NULL;
for( i = 0; i < len; ++i )
output[i] = rand();
#else
if( rng_state != NULL )
rng_state = NULL;
arc4random_buf( output, len );
#endif /* !OpenBSD */
return( 0 );
}
#endif /* MBEDTLS_PKCS1_V15 */
/*
* Checkup routine
*/
int mbedtls_rsa_self_test( int verbose )
{
int ret = 0;
#if defined(MBEDTLS_PKCS1_V15)
size_t len;
mbedtls_rsa_context rsa;
unsigned char rsa_plaintext[PT_LEN];
unsigned char rsa_decrypted[PT_LEN];
unsigned char rsa_ciphertext[KEY_LEN];
#if defined(MBEDTLS_SHA1_C)
unsigned char sha1sum[20];
#endif
mbedtls_rsa_init( &rsa, MBEDTLS_RSA_PKCS_V15, 0 );
rsa.len = KEY_LEN;
MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &rsa.N , 16, RSA_N ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &rsa.E , 16, RSA_E ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &rsa.D , 16, RSA_D ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &rsa.P , 16, RSA_P ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &rsa.Q , 16, RSA_Q ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &rsa.DP, 16, RSA_DP ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &rsa.DQ, 16, RSA_DQ ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &rsa.QP, 16, RSA_QP ) );
if( verbose != 0 )
mbedtls_printf( " RSA key validation: " );
if( mbedtls_rsa_check_pubkey( &rsa ) != 0 ||
mbedtls_rsa_check_privkey( &rsa ) != 0 )
{
if( verbose != 0 )
mbedtls_printf( "failed\n" );
return( 1 );
}
if( verbose != 0 )
mbedtls_printf( "passed\n PKCS#1 encryption : " );
memcpy( rsa_plaintext, RSA_PT, PT_LEN );
if( mbedtls_rsa_pkcs1_encrypt( &rsa, myrand, NULL, MBEDTLS_RSA_PUBLIC, PT_LEN,
rsa_plaintext, rsa_ciphertext ) != 0 )
{
if( verbose != 0 )
mbedtls_printf( "failed\n" );
return( 1 );
}
if( verbose != 0 )
mbedtls_printf( "passed\n PKCS#1 decryption : " );
if( mbedtls_rsa_pkcs1_decrypt( &rsa, myrand, NULL, MBEDTLS_RSA_PRIVATE, &len,
rsa_ciphertext, rsa_decrypted,
sizeof(rsa_decrypted) ) != 0 )
{
if( verbose != 0 )
mbedtls_printf( "failed\n" );
return( 1 );
}
if( memcmp( rsa_decrypted, rsa_plaintext, len ) != 0 )
{
if( verbose != 0 )
mbedtls_printf( "failed\n" );
return( 1 );
}
if( verbose != 0 )
mbedtls_printf( "passed\n" );
#if defined(MBEDTLS_SHA1_C)
if( verbose != 0 )
mbedtls_printf( "PKCS#1 data sign : " );
mbedtls_sha1( rsa_plaintext, PT_LEN, sha1sum );
if( mbedtls_rsa_pkcs1_sign( &rsa, myrand, NULL, MBEDTLS_RSA_PRIVATE, MBEDTLS_MD_SHA1, 0,
sha1sum, rsa_ciphertext ) != 0 )
{
if( verbose != 0 )
mbedtls_printf( "failed\n" );
return( 1 );
}
if( verbose != 0 )
mbedtls_printf( "passed\n PKCS#1 sig. verify: " );
if( mbedtls_rsa_pkcs1_verify( &rsa, NULL, NULL, MBEDTLS_RSA_PUBLIC, MBEDTLS_MD_SHA1, 0,
sha1sum, rsa_ciphertext ) != 0 )
{
if( verbose != 0 )
mbedtls_printf( "failed\n" );
return( 1 );
}
if( verbose != 0 )
mbedtls_printf( "passed\n" );
#endif /* MBEDTLS_SHA1_C */
if( verbose != 0 )
mbedtls_printf( "\n" );
cleanup:
mbedtls_rsa_free( &rsa );
#else /* MBEDTLS_PKCS1_V15 */
((void) verbose);
#endif /* MBEDTLS_PKCS1_V15 */
return( ret );
}
#endif /* MBEDTLS_SELF_TEST */
#endif /* MBEDTLS_RSA_C */