| /* |
| * The RSA public-key cryptosystem |
| * |
| * Copyright (C) 2006-2014, Brainspark B.V. |
| * |
| * This file is part of PolarSSL (http://www.polarssl.org) |
| * Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org> |
| * |
| * All rights reserved. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, write to the Free Software Foundation, Inc., |
| * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| */ |
| /* |
| * 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(POLARSSL_CONFIG_FILE) |
| #include "polarssl/config.h" |
| #else |
| #include POLARSSL_CONFIG_FILE |
| #endif |
| |
| #if defined(POLARSSL_RSA_C) |
| |
| #include "polarssl/rsa.h" |
| #include "polarssl/oid.h" |
| |
| #if defined(POLARSSL_PKCS1_V21) |
| #include "polarssl/md.h" |
| #endif |
| |
| #include <stdlib.h> |
| #include <stdio.h> |
| |
| #if defined(POLARSSL_PLATFORM_C) |
| #include "polarssl/platform.h" |
| #else |
| #define polarssl_printf printf |
| #endif |
| |
| /* |
| * Initialize an RSA context |
| */ |
| void rsa_init( rsa_context *ctx, |
| int padding, |
| int hash_id ) |
| { |
| memset( ctx, 0, sizeof( rsa_context ) ); |
| |
| rsa_set_padding( ctx, padding, hash_id ); |
| |
| #if defined(POLARSSL_THREADING_C) |
| polarssl_mutex_init( &ctx->mutex ); |
| #endif |
| } |
| |
| /* |
| * Set padding for an existing RSA context |
| */ |
| void rsa_set_padding( rsa_context *ctx, int padding, int hash_id ) |
| { |
| ctx->padding = padding; |
| ctx->hash_id = hash_id; |
| } |
| |
| #if defined(POLARSSL_GENPRIME) |
| |
| /* |
| * Generate an RSA keypair |
| */ |
| int rsa_gen_key( rsa_context *ctx, |
| int (*f_rng)(void *, unsigned char *, size_t), |
| void *p_rng, |
| unsigned int nbits, int exponent ) |
| { |
| int ret; |
| mpi P1, Q1, H, G; |
| |
| if( f_rng == NULL || nbits < 128 || exponent < 3 ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| mpi_init( &P1 ); mpi_init( &Q1 ); mpi_init( &H ); mpi_init( &G ); |
| |
| /* |
| * find primes P and Q with Q < P so that: |
| * GCD( E, (P-1)*(Q-1) ) == 1 |
| */ |
| MPI_CHK( mpi_lset( &ctx->E, exponent ) ); |
| |
| do |
| { |
| MPI_CHK( mpi_gen_prime( &ctx->P, ( nbits + 1 ) >> 1, 0, |
| f_rng, p_rng ) ); |
| |
| MPI_CHK( mpi_gen_prime( &ctx->Q, ( nbits + 1 ) >> 1, 0, |
| f_rng, p_rng ) ); |
| |
| if( mpi_cmp_mpi( &ctx->P, &ctx->Q ) < 0 ) |
| mpi_swap( &ctx->P, &ctx->Q ); |
| |
| if( mpi_cmp_mpi( &ctx->P, &ctx->Q ) == 0 ) |
| continue; |
| |
| MPI_CHK( mpi_mul_mpi( &ctx->N, &ctx->P, &ctx->Q ) ); |
| if( mpi_msb( &ctx->N ) != nbits ) |
| continue; |
| |
| MPI_CHK( mpi_sub_int( &P1, &ctx->P, 1 ) ); |
| MPI_CHK( mpi_sub_int( &Q1, &ctx->Q, 1 ) ); |
| MPI_CHK( mpi_mul_mpi( &H, &P1, &Q1 ) ); |
| MPI_CHK( mpi_gcd( &G, &ctx->E, &H ) ); |
| } |
| while( 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 |
| */ |
| MPI_CHK( mpi_inv_mod( &ctx->D , &ctx->E, &H ) ); |
| MPI_CHK( mpi_mod_mpi( &ctx->DP, &ctx->D, &P1 ) ); |
| MPI_CHK( mpi_mod_mpi( &ctx->DQ, &ctx->D, &Q1 ) ); |
| MPI_CHK( mpi_inv_mod( &ctx->QP, &ctx->Q, &ctx->P ) ); |
| |
| ctx->len = ( mpi_msb( &ctx->N ) + 7 ) >> 3; |
| |
| cleanup: |
| |
| mpi_free( &P1 ); mpi_free( &Q1 ); mpi_free( &H ); mpi_free( &G ); |
| |
| if( ret != 0 ) |
| { |
| rsa_free( ctx ); |
| return( POLARSSL_ERR_RSA_KEY_GEN_FAILED + ret ); |
| } |
| |
| return( 0 ); |
| } |
| |
| #endif /* POLARSSL_GENPRIME */ |
| |
| /* |
| * Check a public RSA key |
| */ |
| int rsa_check_pubkey( const rsa_context *ctx ) |
| { |
| if( !ctx->N.p || !ctx->E.p ) |
| return( POLARSSL_ERR_RSA_KEY_CHECK_FAILED ); |
| |
| if( ( ctx->N.p[0] & 1 ) == 0 || |
| ( ctx->E.p[0] & 1 ) == 0 ) |
| return( POLARSSL_ERR_RSA_KEY_CHECK_FAILED ); |
| |
| if( mpi_msb( &ctx->N ) < 128 || |
| mpi_msb( &ctx->N ) > POLARSSL_MPI_MAX_BITS ) |
| return( POLARSSL_ERR_RSA_KEY_CHECK_FAILED ); |
| |
| if( mpi_msb( &ctx->E ) < 2 || |
| mpi_cmp_mpi( &ctx->E, &ctx->N ) >= 0 ) |
| return( POLARSSL_ERR_RSA_KEY_CHECK_FAILED ); |
| |
| return( 0 ); |
| } |
| |
| /* |
| * Check a private RSA key |
| */ |
| int rsa_check_privkey( const rsa_context *ctx ) |
| { |
| int ret; |
| mpi PQ, DE, P1, Q1, H, I, G, G2, L1, L2, DP, DQ, QP; |
| |
| if( ( ret = rsa_check_pubkey( ctx ) ) != 0 ) |
| return( ret ); |
| |
| if( !ctx->P.p || !ctx->Q.p || !ctx->D.p ) |
| return( POLARSSL_ERR_RSA_KEY_CHECK_FAILED ); |
| |
| mpi_init( &PQ ); mpi_init( &DE ); mpi_init( &P1 ); mpi_init( &Q1 ); |
| mpi_init( &H ); mpi_init( &I ); mpi_init( &G ); mpi_init( &G2 ); |
| mpi_init( &L1 ); mpi_init( &L2 ); mpi_init( &DP ); mpi_init( &DQ ); |
| mpi_init( &QP ); |
| |
| MPI_CHK( mpi_mul_mpi( &PQ, &ctx->P, &ctx->Q ) ); |
| MPI_CHK( mpi_mul_mpi( &DE, &ctx->D, &ctx->E ) ); |
| MPI_CHK( mpi_sub_int( &P1, &ctx->P, 1 ) ); |
| MPI_CHK( mpi_sub_int( &Q1, &ctx->Q, 1 ) ); |
| MPI_CHK( mpi_mul_mpi( &H, &P1, &Q1 ) ); |
| MPI_CHK( mpi_gcd( &G, &ctx->E, &H ) ); |
| |
| MPI_CHK( mpi_gcd( &G2, &P1, &Q1 ) ); |
| MPI_CHK( mpi_div_mpi( &L1, &L2, &H, &G2 ) ); |
| MPI_CHK( mpi_mod_mpi( &I, &DE, &L1 ) ); |
| |
| MPI_CHK( mpi_mod_mpi( &DP, &ctx->D, &P1 ) ); |
| MPI_CHK( mpi_mod_mpi( &DQ, &ctx->D, &Q1 ) ); |
| MPI_CHK( mpi_inv_mod( &QP, &ctx->Q, &ctx->P ) ); |
| /* |
| * Check for a valid PKCS1v2 private key |
| */ |
| if( mpi_cmp_mpi( &PQ, &ctx->N ) != 0 || |
| mpi_cmp_mpi( &DP, &ctx->DP ) != 0 || |
| mpi_cmp_mpi( &DQ, &ctx->DQ ) != 0 || |
| mpi_cmp_mpi( &QP, &ctx->QP ) != 0 || |
| mpi_cmp_int( &L2, 0 ) != 0 || |
| mpi_cmp_int( &I, 1 ) != 0 || |
| mpi_cmp_int( &G, 1 ) != 0 ) |
| { |
| ret = POLARSSL_ERR_RSA_KEY_CHECK_FAILED; |
| } |
| |
| cleanup: |
| mpi_free( &PQ ); mpi_free( &DE ); mpi_free( &P1 ); mpi_free( &Q1 ); |
| mpi_free( &H ); mpi_free( &I ); mpi_free( &G ); mpi_free( &G2 ); |
| mpi_free( &L1 ); mpi_free( &L2 ); mpi_free( &DP ); mpi_free( &DQ ); |
| mpi_free( &QP ); |
| |
| if( ret == POLARSSL_ERR_RSA_KEY_CHECK_FAILED ) |
| return( ret ); |
| |
| if( ret != 0 ) |
| return( POLARSSL_ERR_RSA_KEY_CHECK_FAILED + ret ); |
| |
| return( 0 ); |
| } |
| |
| /* |
| * Do an RSA public key operation |
| */ |
| int rsa_public( rsa_context *ctx, |
| const unsigned char *input, |
| unsigned char *output ) |
| { |
| int ret; |
| size_t olen; |
| mpi T; |
| |
| mpi_init( &T ); |
| |
| MPI_CHK( mpi_read_binary( &T, input, ctx->len ) ); |
| |
| if( mpi_cmp_mpi( &T, &ctx->N ) >= 0 ) |
| { |
| mpi_free( &T ); |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| } |
| |
| olen = ctx->len; |
| MPI_CHK( mpi_exp_mod( &T, &T, &ctx->E, &ctx->N, &ctx->RN ) ); |
| MPI_CHK( mpi_write_binary( &T, output, olen ) ); |
| |
| cleanup: |
| |
| mpi_free( &T ); |
| |
| if( ret != 0 ) |
| return( POLARSSL_ERR_RSA_PUBLIC_FAILED + ret ); |
| |
| return( 0 ); |
| } |
| |
| #if !defined(POLARSSL_RSA_NO_CRT) |
| /* |
| * 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( rsa_context *ctx, mpi *Vi, mpi *Vf, |
| int (*f_rng)(void *, unsigned char *, size_t), void *p_rng ) |
| { |
| int ret, count = 0; |
| |
| #if defined(POLARSSL_THREADING_C) |
| polarssl_mutex_lock( &ctx->mutex ); |
| #endif |
| |
| if( ctx->Vf.p != NULL ) |
| { |
| /* We already have blinding values, just update them by squaring */ |
| MPI_CHK( mpi_mul_mpi( &ctx->Vi, &ctx->Vi, &ctx->Vi ) ); |
| MPI_CHK( mpi_mod_mpi( &ctx->Vi, &ctx->Vi, &ctx->N ) ); |
| MPI_CHK( mpi_mul_mpi( &ctx->Vf, &ctx->Vf, &ctx->Vf ) ); |
| MPI_CHK( mpi_mod_mpi( &ctx->Vf, &ctx->Vf, &ctx->N ) ); |
| |
| goto done; |
| } |
| |
| /* Unblinding value: Vf = random number, invertible mod N */ |
| do { |
| if( count++ > 10 ) |
| return( POLARSSL_ERR_RSA_RNG_FAILED ); |
| |
| MPI_CHK( mpi_fill_random( &ctx->Vf, ctx->len - 1, f_rng, p_rng ) ); |
| MPI_CHK( mpi_gcd( &ctx->Vi, &ctx->Vf, &ctx->N ) ); |
| } while( mpi_cmp_int( &ctx->Vi, 1 ) != 0 ); |
| |
| /* Blinding value: Vi = Vf^(-e) mod N */ |
| MPI_CHK( mpi_inv_mod( &ctx->Vi, &ctx->Vf, &ctx->N ) ); |
| MPI_CHK( mpi_exp_mod( &ctx->Vi, &ctx->Vi, &ctx->E, &ctx->N, &ctx->RN ) ); |
| |
| done: |
| if( Vi != &ctx->Vi ) |
| { |
| MPI_CHK( mpi_copy( Vi, &ctx->Vi ) ); |
| MPI_CHK( mpi_copy( Vf, &ctx->Vf ) ); |
| } |
| |
| cleanup: |
| #if defined(POLARSSL_THREADING_C) |
| polarssl_mutex_unlock( &ctx->mutex ); |
| #endif |
| |
| return( ret ); |
| } |
| #endif /* !POLARSSL_RSA_NO_CRT */ |
| |
| /* |
| * Do an RSA private key operation |
| */ |
| int rsa_private( 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; |
| mpi T, T1, T2; |
| #if !defined(POLARSSL_RSA_NO_CRT) |
| mpi *Vi, *Vf; |
| |
| /* |
| * When using the Chinese Remainder Theorem, we use blinding values. |
| * Without threading, we just read them directly from the context, |
| * otherwise we make a local copy in order to reduce locking contention. |
| */ |
| #if defined(POLARSSL_THREADING_C) |
| mpi Vi_copy, Vf_copy; |
| |
| mpi_init( &Vi_copy ); mpi_init( &Vf_copy ); |
| Vi = &Vi_copy; |
| Vf = &Vf_copy; |
| #else |
| Vi = &ctx->Vi; |
| Vf = &ctx->Vf; |
| #endif |
| #endif /* !POLARSSL_RSA_NO_CRT */ |
| |
| mpi_init( &T ); mpi_init( &T1 ); mpi_init( &T2 ); |
| |
| MPI_CHK( mpi_read_binary( &T, input, ctx->len ) ); |
| if( mpi_cmp_mpi( &T, &ctx->N ) >= 0 ) |
| { |
| mpi_free( &T ); |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| } |
| |
| #if defined(POLARSSL_RSA_NO_CRT) |
| ((void) f_rng); |
| ((void) p_rng); |
| MPI_CHK( mpi_exp_mod( &T, &T, &ctx->D, &ctx->N, &ctx->RN ) ); |
| #else |
| if( f_rng != NULL ) |
| { |
| /* |
| * Blinding |
| * T = T * Vi mod N |
| */ |
| MPI_CHK( rsa_prepare_blinding( ctx, Vi, Vf, f_rng, p_rng ) ); |
| MPI_CHK( mpi_mul_mpi( &T, &T, Vi ) ); |
| MPI_CHK( mpi_mod_mpi( &T, &T, &ctx->N ) ); |
| } |
| |
| /* |
| * faster decryption using the CRT |
| * |
| * T1 = input ^ dP mod P |
| * T2 = input ^ dQ mod Q |
| */ |
| MPI_CHK( mpi_exp_mod( &T1, &T, &ctx->DP, &ctx->P, &ctx->RP ) ); |
| MPI_CHK( mpi_exp_mod( &T2, &T, &ctx->DQ, &ctx->Q, &ctx->RQ ) ); |
| |
| /* |
| * T = (T1 - T2) * (Q^-1 mod P) mod P |
| */ |
| MPI_CHK( mpi_sub_mpi( &T, &T1, &T2 ) ); |
| MPI_CHK( mpi_mul_mpi( &T1, &T, &ctx->QP ) ); |
| MPI_CHK( mpi_mod_mpi( &T, &T1, &ctx->P ) ); |
| |
| /* |
| * T = T2 + T * Q |
| */ |
| MPI_CHK( mpi_mul_mpi( &T1, &T, &ctx->Q ) ); |
| MPI_CHK( mpi_add_mpi( &T, &T2, &T1 ) ); |
| |
| if( f_rng != NULL ) |
| { |
| /* |
| * Unblind |
| * T = T * Vf mod N |
| */ |
| MPI_CHK( mpi_mul_mpi( &T, &T, Vf ) ); |
| MPI_CHK( mpi_mod_mpi( &T, &T, &ctx->N ) ); |
| } |
| #endif /* POLARSSL_RSA_NO_CRT */ |
| |
| olen = ctx->len; |
| MPI_CHK( mpi_write_binary( &T, output, olen ) ); |
| |
| cleanup: |
| mpi_free( &T ); mpi_free( &T1 ); mpi_free( &T2 ); |
| #if !defined(POLARSSL_RSA_NO_CRT) && defined(POLARSSL_THREADING_C) |
| mpi_free( &Vi_copy ); mpi_free( &Vf_copy ); |
| #endif |
| |
| if( ret != 0 ) |
| return( POLARSSL_ERR_RSA_PRIVATE_FAILED + ret ); |
| |
| return( 0 ); |
| } |
| |
| #if defined(POLARSSL_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, md_context_t *md_ctx ) |
| { |
| unsigned char mask[POLARSSL_MD_MAX_SIZE]; |
| unsigned char counter[4]; |
| unsigned char *p; |
| unsigned int hlen; |
| size_t i, use_len; |
| |
| memset( mask, 0, POLARSSL_MD_MAX_SIZE ); |
| memset( counter, 0, 4 ); |
| |
| hlen = md_ctx->md_info->size; |
| |
| // Generate and apply dbMask |
| // |
| p = dst; |
| |
| while( dlen > 0 ) |
| { |
| use_len = hlen; |
| if( dlen < hlen ) |
| use_len = dlen; |
| |
| md_starts( md_ctx ); |
| md_update( md_ctx, src, slen ); |
| md_update( md_ctx, counter, 4 ); |
| md_finish( md_ctx, mask ); |
| |
| for( i = 0; i < use_len; ++i ) |
| *p++ ^= mask[i]; |
| |
| counter[3]++; |
| |
| dlen -= use_len; |
| } |
| } |
| #endif /* POLARSSL_PKCS1_V21 */ |
| |
| #if defined(POLARSSL_PKCS1_V21) |
| /* |
| * Implementation of the PKCS#1 v2.1 RSAES-OAEP-ENCRYPT function |
| */ |
| int rsa_rsaes_oaep_encrypt( 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 md_info_t *md_info; |
| md_context_t md_ctx; |
| |
| if( ctx->padding != RSA_PKCS_V21 || f_rng == NULL ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| md_info = md_info_from_type( ctx->hash_id ); |
| if( md_info == NULL ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| olen = ctx->len; |
| hlen = md_get_size( md_info ); |
| |
| if( olen < ilen + 2 * hlen + 2 || f_rng == NULL ) |
| return( POLARSSL_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( POLARSSL_ERR_RSA_RNG_FAILED + ret ); |
| |
| p += hlen; |
| |
| // Construct DB |
| // |
| md( md_info, label, label_len, p ); |
| p += hlen; |
| p += olen - 2 * hlen - 2 - ilen; |
| *p++ = 1; |
| memcpy( p, input, ilen ); |
| |
| md_init_ctx( &md_ctx, md_info ); |
| |
| // 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 ); |
| |
| md_free_ctx( &md_ctx ); |
| |
| return( ( mode == RSA_PUBLIC ) |
| ? rsa_public( ctx, output, output ) |
| : rsa_private( ctx, f_rng, p_rng, output, output ) ); |
| } |
| #endif /* POLARSSL_PKCS1_V21 */ |
| |
| #if defined(POLARSSL_PKCS1_V15) |
| /* |
| * Implementation of the PKCS#1 v2.1 RSAES-PKCS1-V1_5-ENCRYPT function |
| */ |
| int rsa_rsaes_pkcs1_v15_encrypt( 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( ctx->padding != RSA_PKCS_V15 || f_rng == NULL ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| olen = ctx->len; |
| |
| if( olen < ilen + 11 ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| nb_pad = olen - 3 - ilen; |
| |
| *p++ = 0; |
| if( mode == RSA_PUBLIC ) |
| { |
| *p++ = 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 POLARSSL_ERR_RSA_RNG_FAILED + ret; |
| |
| p++; |
| } |
| } |
| else |
| { |
| *p++ = RSA_SIGN; |
| |
| while( nb_pad-- > 0 ) |
| *p++ = 0xFF; |
| } |
| |
| *p++ = 0; |
| memcpy( p, input, ilen ); |
| |
| return( ( mode == RSA_PUBLIC ) |
| ? rsa_public( ctx, output, output ) |
| : rsa_private( ctx, f_rng, p_rng, output, output ) ); |
| } |
| #endif /* POLARSSL_PKCS1_V15 */ |
| |
| /* |
| * Add the message padding, then do an RSA operation |
| */ |
| int rsa_pkcs1_encrypt( 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(POLARSSL_PKCS1_V15) |
| case RSA_PKCS_V15: |
| return rsa_rsaes_pkcs1_v15_encrypt( ctx, f_rng, p_rng, mode, ilen, |
| input, output ); |
| #endif |
| |
| #if defined(POLARSSL_PKCS1_V21) |
| case RSA_PKCS_V21: |
| return rsa_rsaes_oaep_encrypt( ctx, f_rng, p_rng, mode, NULL, 0, |
| ilen, input, output ); |
| #endif |
| |
| default: |
| return( POLARSSL_ERR_RSA_INVALID_PADDING ); |
| } |
| } |
| |
| #if defined(POLARSSL_PKCS1_V21) |
| /* |
| * Implementation of the PKCS#1 v2.1 RSAES-OAEP-DECRYPT function |
| */ |
| int rsa_rsaes_oaep_decrypt( 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[POLARSSL_MPI_MAX_SIZE]; |
| unsigned char lhash[POLARSSL_MD_MAX_SIZE]; |
| unsigned int hlen; |
| const md_info_t *md_info; |
| md_context_t md_ctx; |
| |
| /* |
| * Parameters sanity checks |
| */ |
| if( ctx->padding != RSA_PKCS_V21 ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| ilen = ctx->len; |
| |
| if( ilen < 16 || ilen > sizeof( buf ) ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| md_info = md_info_from_type( ctx->hash_id ); |
| if( md_info == NULL ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| /* |
| * RSA operation |
| */ |
| ret = ( mode == RSA_PUBLIC ) |
| ? rsa_public( ctx, input, buf ) |
| : rsa_private( ctx, f_rng, p_rng, input, buf ); |
| |
| if( ret != 0 ) |
| return( ret ); |
| |
| /* |
| * Unmask data and generate lHash |
| */ |
| hlen = md_get_size( md_info ); |
| |
| md_init_ctx( &md_ctx, md_info ); |
| |
| /* Generate lHash */ |
| 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 ); |
| |
| md_free_ctx( &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 == 0 ); |
| } |
| |
| 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( POLARSSL_ERR_RSA_INVALID_PADDING ); |
| |
| if (ilen - (p - buf) > output_max_len) |
| return( POLARSSL_ERR_RSA_OUTPUT_TOO_LARGE ); |
| |
| *olen = ilen - (p - buf); |
| memcpy( output, p, *olen ); |
| |
| return( 0 ); |
| } |
| #endif /* POLARSSL_PKCS1_V21 */ |
| |
| #if defined(POLARSSL_PKCS1_V15) |
| /* |
| * Implementation of the PKCS#1 v2.1 RSAES-PKCS1-V1_5-DECRYPT function |
| */ |
| int rsa_rsaes_pkcs1_v15_decrypt( 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[POLARSSL_MPI_MAX_SIZE]; |
| |
| if( ctx->padding != RSA_PKCS_V15 ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| ilen = ctx->len; |
| |
| if( ilen < 16 || ilen > sizeof( buf ) ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| ret = ( mode == RSA_PUBLIC ) |
| ? rsa_public( ctx, input, buf ) |
| : 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 == RSA_PRIVATE ) |
| { |
| bad |= *p++ ^ 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] == 0 ); |
| pad_count += ( pad_done == 0 ); |
| } |
| |
| p += pad_count; |
| bad |= *p++; /* Must be zero */ |
| } |
| else |
| { |
| bad |= *p++ ^ 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( POLARSSL_ERR_RSA_INVALID_PADDING ); |
| |
| if (ilen - (p - buf) > output_max_len) |
| return( POLARSSL_ERR_RSA_OUTPUT_TOO_LARGE ); |
| |
| *olen = ilen - (p - buf); |
| memcpy( output, p, *olen ); |
| |
| return( 0 ); |
| } |
| #endif /* POLARSSL_PKCS1_V15 */ |
| |
| /* |
| * Do an RSA operation, then remove the message padding |
| */ |
| int rsa_pkcs1_decrypt( 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(POLARSSL_PKCS1_V15) |
| case RSA_PKCS_V15: |
| return rsa_rsaes_pkcs1_v15_decrypt( ctx, f_rng, p_rng, mode, olen, |
| input, output, output_max_len ); |
| #endif |
| |
| #if defined(POLARSSL_PKCS1_V21) |
| case RSA_PKCS_V21: |
| return rsa_rsaes_oaep_decrypt( ctx, f_rng, p_rng, mode, NULL, 0, |
| olen, input, output, |
| output_max_len ); |
| #endif |
| |
| default: |
| return( POLARSSL_ERR_RSA_INVALID_PADDING ); |
| } |
| } |
| |
| #if defined(POLARSSL_PKCS1_V21) |
| /* |
| * Implementation of the PKCS#1 v2.1 RSASSA-PSS-SIGN function |
| */ |
| int rsa_rsassa_pss_sign( rsa_context *ctx, |
| int (*f_rng)(void *, unsigned char *, size_t), |
| void *p_rng, |
| int mode, |
| 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[POLARSSL_MD_MAX_SIZE]; |
| unsigned int slen, hlen, offset = 0; |
| int ret; |
| size_t msb; |
| const md_info_t *md_info; |
| md_context_t md_ctx; |
| |
| if( ctx->padding != RSA_PKCS_V21 || f_rng == NULL ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| olen = ctx->len; |
| |
| if( md_alg != POLARSSL_MD_NONE ) |
| { |
| // Gather length of hash to sign |
| // |
| md_info = md_info_from_type( md_alg ); |
| if( md_info == NULL ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| hashlen = md_get_size( md_info ); |
| } |
| |
| md_info = md_info_from_type( ctx->hash_id ); |
| if( md_info == NULL ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| hlen = md_get_size( md_info ); |
| slen = hlen; |
| |
| if( olen < hlen + slen + 2 ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| memset( sig, 0, olen ); |
| |
| // Generate salt of length slen |
| // |
| if( ( ret = f_rng( p_rng, salt, slen ) ) != 0 ) |
| return( POLARSSL_ERR_RSA_RNG_FAILED + ret ); |
| |
| // Note: EMSA-PSS encoding is over the length of N - 1 bits |
| // |
| msb = mpi_msb( &ctx->N ) - 1; |
| p += olen - hlen * 2 - 2; |
| *p++ = 0x01; |
| memcpy( p, salt, slen ); |
| p += slen; |
| |
| md_init_ctx( &md_ctx, md_info ); |
| |
| // Generate H = Hash( M' ) |
| // |
| md_starts( &md_ctx ); |
| md_update( &md_ctx, p, 8 ); |
| md_update( &md_ctx, hash, hashlen ); |
| md_update( &md_ctx, salt, slen ); |
| 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 ); |
| |
| md_free_ctx( &md_ctx ); |
| |
| msb = mpi_msb( &ctx->N ) - 1; |
| sig[0] &= 0xFF >> ( olen * 8 - msb ); |
| |
| p += hlen; |
| *p++ = 0xBC; |
| |
| return( ( mode == RSA_PUBLIC ) |
| ? rsa_public( ctx, sig, sig ) |
| : rsa_private( ctx, f_rng, p_rng, sig, sig ) ); |
| } |
| #endif /* POLARSSL_PKCS1_V21 */ |
| |
| #if defined(POLARSSL_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 rsa_rsassa_pkcs1_v15_sign( rsa_context *ctx, |
| int (*f_rng)(void *, unsigned char *, size_t), |
| void *p_rng, |
| int mode, |
| 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; |
| |
| if( ctx->padding != RSA_PKCS_V15 ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| olen = ctx->len; |
| nb_pad = olen - 3; |
| |
| if( md_alg != POLARSSL_MD_NONE ) |
| { |
| const md_info_t *md_info = md_info_from_type( md_alg ); |
| if( md_info == NULL ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| if( oid_get_oid_by_md( md_alg, &oid, &oid_size ) != 0 ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| nb_pad -= 10 + oid_size; |
| |
| hashlen = md_get_size( md_info ); |
| } |
| |
| nb_pad -= hashlen; |
| |
| if( ( nb_pad < 8 ) || ( nb_pad > olen ) ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| *p++ = 0; |
| *p++ = RSA_SIGN; |
| memset( p, 0xFF, nb_pad ); |
| p += nb_pad; |
| *p++ = 0; |
| |
| if( md_alg == POLARSSL_MD_NONE ) |
| { |
| memcpy( p, hash, hashlen ); |
| } |
| else |
| { |
| /* |
| * DigestInfo ::= SEQUENCE { |
| * digestAlgorithm DigestAlgorithmIdentifier, |
| * digest Digest } |
| * |
| * DigestAlgorithmIdentifier ::= AlgorithmIdentifier |
| * |
| * Digest ::= OCTET STRING |
| */ |
| *p++ = ASN1_SEQUENCE | ASN1_CONSTRUCTED; |
| *p++ = (unsigned char) ( 0x08 + oid_size + hashlen ); |
| *p++ = ASN1_SEQUENCE | ASN1_CONSTRUCTED; |
| *p++ = (unsigned char) ( 0x04 + oid_size ); |
| *p++ = ASN1_OID; |
| *p++ = oid_size & 0xFF; |
| memcpy( p, oid, oid_size ); |
| p += oid_size; |
| *p++ = ASN1_NULL; |
| *p++ = 0x00; |
| *p++ = ASN1_OCTET_STRING; |
| *p++ = hashlen; |
| memcpy( p, hash, hashlen ); |
| } |
| |
| return( ( mode == RSA_PUBLIC ) |
| ? rsa_public( ctx, sig, sig ) |
| : rsa_private( ctx, f_rng, p_rng, sig, sig ) ); |
| } |
| #endif /* POLARSSL_PKCS1_V15 */ |
| |
| /* |
| * Do an RSA operation to sign the message digest |
| */ |
| int rsa_pkcs1_sign( rsa_context *ctx, |
| int (*f_rng)(void *, unsigned char *, size_t), |
| void *p_rng, |
| int mode, |
| md_type_t md_alg, |
| unsigned int hashlen, |
| const unsigned char *hash, |
| unsigned char *sig ) |
| { |
| switch( ctx->padding ) |
| { |
| #if defined(POLARSSL_PKCS1_V15) |
| case RSA_PKCS_V15: |
| return rsa_rsassa_pkcs1_v15_sign( ctx, f_rng, p_rng, mode, md_alg, |
| hashlen, hash, sig ); |
| #endif |
| |
| #if defined(POLARSSL_PKCS1_V21) |
| case RSA_PKCS_V21: |
| return rsa_rsassa_pss_sign( ctx, f_rng, p_rng, mode, md_alg, |
| hashlen, hash, sig ); |
| #endif |
| |
| default: |
| return( POLARSSL_ERR_RSA_INVALID_PADDING ); |
| } |
| } |
| |
| #if defined(POLARSSL_PKCS1_V21) |
| /* |
| * Implementation of the PKCS#1 v2.1 RSASSA-PSS-VERIFY function |
| */ |
| int rsa_rsassa_pss_verify( rsa_context *ctx, |
| int (*f_rng)(void *, unsigned char *, size_t), |
| void *p_rng, |
| int mode, |
| md_type_t md_alg, |
| unsigned int hashlen, |
| const unsigned char *hash, |
| const unsigned char *sig ) |
| { |
| int ret; |
| size_t siglen; |
| unsigned char *p; |
| unsigned char buf[POLARSSL_MPI_MAX_SIZE]; |
| unsigned char result[POLARSSL_MD_MAX_SIZE]; |
| unsigned char zeros[8]; |
| unsigned int hlen; |
| size_t slen, msb; |
| const md_info_t *md_info; |
| md_context_t md_ctx; |
| |
| if( ctx->padding != RSA_PKCS_V21 ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| siglen = ctx->len; |
| |
| if( siglen < 16 || siglen > sizeof( buf ) ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| ret = ( mode == RSA_PUBLIC ) |
| ? rsa_public( ctx, sig, buf ) |
| : rsa_private( ctx, f_rng, p_rng, sig, buf ); |
| |
| if( ret != 0 ) |
| return( ret ); |
| |
| p = buf; |
| |
| if( buf[siglen - 1] != 0xBC ) |
| return( POLARSSL_ERR_RSA_INVALID_PADDING ); |
| |
| if( md_alg != POLARSSL_MD_NONE ) |
| { |
| // Gather length of hash to sign |
| // |
| md_info = md_info_from_type( md_alg ); |
| if( md_info == NULL ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| hashlen = md_get_size( md_info ); |
| } |
| |
| md_info = md_info_from_type( ctx->hash_id ); |
| if( md_info == NULL ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| hlen = md_get_size( md_info ); |
| slen = siglen - hlen - 1; |
| |
| memset( zeros, 0, 8 ); |
| |
| // Note: EMSA-PSS verification is over the length of N - 1 bits |
| // |
| msb = mpi_msb( &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( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| md_init_ctx( &md_ctx, md_info ); |
| |
| 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 ) |
| { |
| md_free_ctx( &md_ctx ); |
| return( POLARSSL_ERR_RSA_INVALID_PADDING ); |
| } |
| |
| slen -= p - buf; |
| |
| // Generate H = Hash( M' ) |
| // |
| md_starts( &md_ctx ); |
| md_update( &md_ctx, zeros, 8 ); |
| md_update( &md_ctx, hash, hashlen ); |
| md_update( &md_ctx, p, slen ); |
| md_finish( &md_ctx, result ); |
| |
| md_free_ctx( &md_ctx ); |
| |
| if( memcmp( p + slen, result, hlen ) == 0 ) |
| return( 0 ); |
| else |
| return( POLARSSL_ERR_RSA_VERIFY_FAILED ); |
| } |
| #endif /* POLARSSL_PKCS1_V21 */ |
| |
| #if defined(POLARSSL_PKCS1_V15) |
| /* |
| * Implementation of the PKCS#1 v2.1 RSASSA-PKCS1-v1_5-VERIFY function |
| */ |
| int rsa_rsassa_pkcs1_v15_verify( rsa_context *ctx, |
| int (*f_rng)(void *, unsigned char *, size_t), |
| void *p_rng, |
| int mode, |
| 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[POLARSSL_MPI_MAX_SIZE]; |
| md_type_t msg_md_alg; |
| const md_info_t *md_info; |
| asn1_buf oid; |
| |
| if( ctx->padding != RSA_PKCS_V15 ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| siglen = ctx->len; |
| |
| if( siglen < 16 || siglen > sizeof( buf ) ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| |
| ret = ( mode == RSA_PUBLIC ) |
| ? rsa_public( ctx, sig, buf ) |
| : rsa_private( ctx, f_rng, p_rng, sig, buf ); |
| |
| if( ret != 0 ) |
| return( ret ); |
| |
| p = buf; |
| |
| if( *p++ != 0 || *p++ != RSA_SIGN ) |
| return( POLARSSL_ERR_RSA_INVALID_PADDING ); |
| |
| while( *p != 0 ) |
| { |
| if( p >= buf + siglen - 1 || *p != 0xFF ) |
| return( POLARSSL_ERR_RSA_INVALID_PADDING ); |
| p++; |
| } |
| p++; |
| |
| len = siglen - ( p - buf ); |
| |
| if( len == hashlen && md_alg == POLARSSL_MD_NONE ) |
| { |
| if( memcmp( p, hash, hashlen ) == 0 ) |
| return( 0 ); |
| else |
| return( POLARSSL_ERR_RSA_VERIFY_FAILED ); |
| } |
| |
| md_info = md_info_from_type( md_alg ); |
| if( md_info == NULL ) |
| return( POLARSSL_ERR_RSA_BAD_INPUT_DATA ); |
| hashlen = md_get_size( md_info ); |
| |
| end = p + len; |
| |
| // Parse the ASN.1 structure inside the PKCS#1 v1.5 structure |
| // |
| if( ( ret = asn1_get_tag( &p, end, &asn1_len, |
| ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 ) |
| return( POLARSSL_ERR_RSA_VERIFY_FAILED ); |
| |
| if( asn1_len + 2 != len ) |
| return( POLARSSL_ERR_RSA_VERIFY_FAILED ); |
| |
| if( ( ret = asn1_get_tag( &p, end, &asn1_len, |
| ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 ) |
| return( POLARSSL_ERR_RSA_VERIFY_FAILED ); |
| |
| if( asn1_len + 6 + hashlen != len ) |
| return( POLARSSL_ERR_RSA_VERIFY_FAILED ); |
| |
| if( ( ret = asn1_get_tag( &p, end, &oid.len, ASN1_OID ) ) != 0 ) |
| return( POLARSSL_ERR_RSA_VERIFY_FAILED ); |
| |
| oid.p = p; |
| p += oid.len; |
| |
| if( oid_get_md_alg( &oid, &msg_md_alg ) != 0 ) |
| return( POLARSSL_ERR_RSA_VERIFY_FAILED ); |
| |
| if( md_alg != msg_md_alg ) |
| return( POLARSSL_ERR_RSA_VERIFY_FAILED ); |
| |
| /* |
| * assume the algorithm parameters must be NULL |
| */ |
| if( ( ret = asn1_get_tag( &p, end, &asn1_len, ASN1_NULL ) ) != 0 ) |
| return( POLARSSL_ERR_RSA_VERIFY_FAILED ); |
| |
| if( ( ret = asn1_get_tag( &p, end, &asn1_len, ASN1_OCTET_STRING ) ) != 0 ) |
| return( POLARSSL_ERR_RSA_VERIFY_FAILED ); |
| |
| if( asn1_len != hashlen ) |
| return( POLARSSL_ERR_RSA_VERIFY_FAILED ); |
| |
| if( memcmp( p, hash, hashlen ) != 0 ) |
| return( POLARSSL_ERR_RSA_VERIFY_FAILED ); |
| |
| p += hashlen; |
| |
| if( p != end ) |
| return( POLARSSL_ERR_RSA_VERIFY_FAILED ); |
| |
| return( 0 ); |
| } |
| #endif /* POLARSSL_PKCS1_V15 */ |
| |
| /* |
| * Do an RSA operation and check the message digest |
| */ |
| int rsa_pkcs1_verify( rsa_context *ctx, |
| int (*f_rng)(void *, unsigned char *, size_t), |
| void *p_rng, |
| int mode, |
| md_type_t md_alg, |
| unsigned int hashlen, |
| const unsigned char *hash, |
| const unsigned char *sig ) |
| { |
| switch( ctx->padding ) |
| { |
| #if defined(POLARSSL_PKCS1_V15) |
| case RSA_PKCS_V15: |
| return rsa_rsassa_pkcs1_v15_verify( ctx, f_rng, p_rng, mode, md_alg, |
| hashlen, hash, sig ); |
| #endif |
| |
| #if defined(POLARSSL_PKCS1_V21) |
| case RSA_PKCS_V21: |
| return rsa_rsassa_pss_verify( ctx, f_rng, p_rng, mode, md_alg, |
| hashlen, hash, sig ); |
| #endif |
| |
| default: |
| return( POLARSSL_ERR_RSA_INVALID_PADDING ); |
| } |
| } |
| |
| /* |
| * Copy the components of an RSA key |
| */ |
| int rsa_copy( rsa_context *dst, const rsa_context *src ) |
| { |
| int ret; |
| |
| dst->ver = src->ver; |
| dst->len = src->len; |
| |
| MPI_CHK( mpi_copy( &dst->N, &src->N ) ); |
| MPI_CHK( mpi_copy( &dst->E, &src->E ) ); |
| |
| MPI_CHK( mpi_copy( &dst->D, &src->D ) ); |
| MPI_CHK( mpi_copy( &dst->P, &src->P ) ); |
| MPI_CHK( mpi_copy( &dst->Q, &src->Q ) ); |
| MPI_CHK( mpi_copy( &dst->DP, &src->DP ) ); |
| MPI_CHK( mpi_copy( &dst->DQ, &src->DQ ) ); |
| MPI_CHK( mpi_copy( &dst->QP, &src->QP ) ); |
| |
| MPI_CHK( mpi_copy( &dst->RN, &src->RN ) ); |
| MPI_CHK( mpi_copy( &dst->RP, &src->RP ) ); |
| MPI_CHK( mpi_copy( &dst->RQ, &src->RQ ) ); |
| |
| #if !defined(POLARSSL_RSA_NO_CRT) |
| MPI_CHK( mpi_copy( &dst->Vi, &src->Vi ) ); |
| MPI_CHK( mpi_copy( &dst->Vf, &src->Vf ) ); |
| #endif |
| |
| dst->padding = src->padding; |
| dst->hash_id = src->hash_id; |
| |
| cleanup: |
| if( ret != 0 ) |
| rsa_free( dst ); |
| |
| return( ret ); |
| } |
| |
| /* |
| * Free the components of an RSA key |
| */ |
| void rsa_free( rsa_context *ctx ) |
| { |
| #if !defined(POLARSSL_RSA_NO_CRT) |
| mpi_free( &ctx->Vi ); mpi_free( &ctx->Vf ); |
| #endif |
| mpi_free( &ctx->RQ ); mpi_free( &ctx->RP ); mpi_free( &ctx->RN ); |
| mpi_free( &ctx->QP ); mpi_free( &ctx->DQ ); mpi_free( &ctx->DP ); |
| mpi_free( &ctx->Q ); mpi_free( &ctx->P ); mpi_free( &ctx->D ); |
| mpi_free( &ctx->E ); mpi_free( &ctx->N ); |
| |
| #if defined(POLARSSL_THREADING_C) |
| polarssl_mutex_free( &ctx->mutex ); |
| #endif |
| } |
| |
| #if defined(POLARSSL_SELF_TEST) |
| |
| #include "polarssl/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(POLARSSL_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 /* POLARSSL_PKCS1_V15 */ |
| |
| /* |
| * Checkup routine |
| */ |
| int rsa_self_test( int verbose ) |
| { |
| int ret = 0; |
| #if defined(POLARSSL_PKCS1_V15) |
| size_t len; |
| rsa_context rsa; |
| unsigned char rsa_plaintext[PT_LEN]; |
| unsigned char rsa_decrypted[PT_LEN]; |
| unsigned char rsa_ciphertext[KEY_LEN]; |
| #if defined(POLARSSL_SHA1_C) |
| unsigned char sha1sum[20]; |
| #endif |
| |
| rsa_init( &rsa, RSA_PKCS_V15, 0 ); |
| |
| rsa.len = KEY_LEN; |
| MPI_CHK( mpi_read_string( &rsa.N , 16, RSA_N ) ); |
| MPI_CHK( mpi_read_string( &rsa.E , 16, RSA_E ) ); |
| MPI_CHK( mpi_read_string( &rsa.D , 16, RSA_D ) ); |
| MPI_CHK( mpi_read_string( &rsa.P , 16, RSA_P ) ); |
| MPI_CHK( mpi_read_string( &rsa.Q , 16, RSA_Q ) ); |
| MPI_CHK( mpi_read_string( &rsa.DP, 16, RSA_DP ) ); |
| MPI_CHK( mpi_read_string( &rsa.DQ, 16, RSA_DQ ) ); |
| MPI_CHK( mpi_read_string( &rsa.QP, 16, RSA_QP ) ); |
| |
| if( verbose != 0 ) |
| polarssl_printf( " RSA key validation: " ); |
| |
| if( rsa_check_pubkey( &rsa ) != 0 || |
| rsa_check_privkey( &rsa ) != 0 ) |
| { |
| if( verbose != 0 ) |
| polarssl_printf( "failed\n" ); |
| |
| return( 1 ); |
| } |
| |
| if( verbose != 0 ) |
| polarssl_printf( "passed\n PKCS#1 encryption : " ); |
| |
| memcpy( rsa_plaintext, RSA_PT, PT_LEN ); |
| |
| if( rsa_pkcs1_encrypt( &rsa, myrand, NULL, RSA_PUBLIC, PT_LEN, |
| rsa_plaintext, rsa_ciphertext ) != 0 ) |
| { |
| if( verbose != 0 ) |
| polarssl_printf( "failed\n" ); |
| |
| return( 1 ); |
| } |
| |
| if( verbose != 0 ) |
| polarssl_printf( "passed\n PKCS#1 decryption : " ); |
| |
| if( rsa_pkcs1_decrypt( &rsa, myrand, NULL, RSA_PRIVATE, &len, |
| rsa_ciphertext, rsa_decrypted, |
| sizeof(rsa_decrypted) ) != 0 ) |
| { |
| if( verbose != 0 ) |
| polarssl_printf( "failed\n" ); |
| |
| return( 1 ); |
| } |
| |
| if( memcmp( rsa_decrypted, rsa_plaintext, len ) != 0 ) |
| { |
| if( verbose != 0 ) |
| polarssl_printf( "failed\n" ); |
| |
| return( 1 ); |
| } |
| |
| #if defined(POLARSSL_SHA1_C) |
| if( verbose != 0 ) |
| polarssl_printf( "passed\n PKCS#1 data sign : " ); |
| |
| sha1( rsa_plaintext, PT_LEN, sha1sum ); |
| |
| if( rsa_pkcs1_sign( &rsa, myrand, NULL, RSA_PRIVATE, POLARSSL_MD_SHA1, 0, |
| sha1sum, rsa_ciphertext ) != 0 ) |
| { |
| if( verbose != 0 ) |
| polarssl_printf( "failed\n" ); |
| |
| return( 1 ); |
| } |
| |
| if( verbose != 0 ) |
| polarssl_printf( "passed\n PKCS#1 sig. verify: " ); |
| |
| if( rsa_pkcs1_verify( &rsa, NULL, NULL, RSA_PUBLIC, POLARSSL_MD_SHA1, 0, |
| sha1sum, rsa_ciphertext ) != 0 ) |
| { |
| if( verbose != 0 ) |
| polarssl_printf( "failed\n" ); |
| |
| return( 1 ); |
| } |
| |
| if( verbose != 0 ) |
| polarssl_printf( "passed\n\n" ); |
| #endif /* POLARSSL_SHA1_C */ |
| |
| cleanup: |
| rsa_free( &rsa ); |
| #else /* POLARSSL_PKCS1_V15 */ |
| ((void) verbose); |
| #endif /* POLARSSL_PKCS1_V15 */ |
| return( ret ); |
| } |
| |
| #endif /* POLARSSL_SELF_TEST */ |
| |
| #endif /* POLARSSL_RSA_C */ |
