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author | Werner Koch <[email protected]> | 2000-12-19 17:20:22 +0000 |
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committer | Werner Koch <[email protected]> | 2000-12-19 17:20:22 +0000 |
commit | 07ca4eaa9d8df67acdccc86c782bcef685d49e2c (patch) | |
tree | 2876cad5493c5f4efa6c85e591dbe7cc26abadf0 /cipher/rsa.c | |
parent | About to release 1.1.2 (diff) | |
download | gnupg-07ca4eaa9d8df67acdccc86c782bcef685d49e2c.tar.gz gnupg-07ca4eaa9d8df67acdccc86c782bcef685d49e2c.zip |
Removed files from the HEAD revision, because they are now in another
repository
Diffstat (limited to 'cipher/rsa.c')
-rw-r--r-- | cipher/rsa.c | 468 |
1 files changed, 0 insertions, 468 deletions
diff --git a/cipher/rsa.c b/cipher/rsa.c deleted file mode 100644 index e7ecccbc2..000000000 --- a/cipher/rsa.c +++ /dev/null @@ -1,468 +0,0 @@ -/* rsa.c - RSA function - * Copyright (C) 1997, 1998, 1999 by Werner Koch (dd9jn) - * Copyright (C) 2000 Free Software Foundation, Inc. - * - * This file is part of GnuPG. - * - * GnuPG 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. - * - * GnuPG 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA - */ - -/* This code uses an algorithm protected by U.S. Patent #4,405,829 - which expires on September 20, 2000. The patent holder placed that - patent into the public domain on Sep 6th, 2000. -*/ - -#include <config.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include "g10lib.h" -#include "mpi.h" -#include "cipher.h" -#include "rsa.h" - - -typedef struct { - MPI n; /* modulus */ - MPI e; /* exponent */ -} RSA_public_key; - - -typedef struct { - MPI n; /* public modulus */ - MPI e; /* public exponent */ - MPI d; /* exponent */ - MPI p; /* prime p. */ - MPI q; /* prime q. */ - MPI u; /* inverse of p mod q. */ -} RSA_secret_key; - - -static void test_keys( RSA_secret_key *sk, unsigned nbits ); -static void generate( RSA_secret_key *sk, unsigned nbits ); -static int check_secret_key( RSA_secret_key *sk ); -static void public(MPI output, MPI input, RSA_public_key *skey ); -static void secret(MPI output, MPI input, RSA_secret_key *skey ); - - -static void -test_keys( RSA_secret_key *sk, unsigned nbits ) -{ - RSA_public_key pk; - MPI test = gcry_mpi_new ( nbits ); - MPI out1 = gcry_mpi_new ( nbits ); - MPI out2 = gcry_mpi_new ( nbits ); - - pk.n = sk->n; - pk.e = sk->e; - gcry_mpi_randomize( test, nbits, GCRY_WEAK_RANDOM ); - - public( out1, test, &pk ); - secret( out2, out1, sk ); - if( mpi_cmp( test, out2 ) ) - log_fatal("RSA operation: public, secret failed\n"); - secret( out1, test, sk ); - public( out2, out1, &pk ); - if( mpi_cmp( test, out2 ) ) - log_fatal("RSA operation: secret, public failed\n"); - gcry_mpi_release ( test ); - gcry_mpi_release ( out1 ); - gcry_mpi_release ( out2 ); -} - -/**************** - * Generate a key pair with a key of size NBITS - * Returns: 2 structures filles with all needed values - */ -static void -generate( RSA_secret_key *sk, unsigned nbits ) -{ - MPI p, q; /* the two primes */ - MPI d; /* the private key */ - MPI u; - MPI t1, t2; - MPI n; /* the public key */ - MPI e; /* the exponent */ - MPI phi; /* helper: (p-a)(q-1) */ - MPI g; - MPI f; - - /* select two (very secret) primes */ - p = generate_secret_prime( nbits / 2 ); - q = generate_secret_prime( nbits / 2 ); - if( mpi_cmp( p, q ) > 0 ) /* p shall be smaller than q (for calc of u)*/ - mpi_swap(p,q); - /* calculate Euler totient: phi = (p-1)(q-1) */ - t1 = mpi_alloc_secure( mpi_get_nlimbs(p) ); - t2 = mpi_alloc_secure( mpi_get_nlimbs(p) ); - phi = gcry_mpi_snew ( nbits ); - g = gcry_mpi_snew ( nbits ); - f = gcry_mpi_snew ( nbits ); - mpi_sub_ui( t1, p, 1 ); - mpi_sub_ui( t2, q, 1 ); - mpi_mul( phi, t1, t2 ); - mpi_gcd(g, t1, t2); - mpi_fdiv_q(f, phi, g); - /* multiply them to make the private key */ - n = gcry_mpi_new ( nbits ); - mpi_mul( n, p, q ); - /* find a public exponent */ - e = gcry_mpi_new ( 6 ); - mpi_set_ui( e, 17); /* start with 17 */ - while( !mpi_gcd(t1, e, phi) ) /* (while gcd is not 1) */ - mpi_add_ui( e, e, 2); - /* calculate the secret key d = e^1 mod phi */ - d = gcry_mpi_snew ( nbits ); - mpi_invm(d, e, f ); - /* calculate the inverse of p and q (used for chinese remainder theorem)*/ - u = gcry_mpi_snew ( nbits ); - mpi_invm(u, p, q ); - - if( DBG_CIPHER ) { - log_mpidump(" p= ", p ); - log_mpidump(" q= ", q ); - log_mpidump("phi= ", phi ); - log_mpidump(" g= ", g ); - log_mpidump(" f= ", f ); - log_mpidump(" n= ", n ); - log_mpidump(" e= ", e ); - log_mpidump(" d= ", d ); - log_mpidump(" u= ", u ); - } - - gcry_mpi_release (t1); - gcry_mpi_release (t2); - gcry_mpi_release (phi); - gcry_mpi_release (f); - gcry_mpi_release (g); - - sk->n = n; - sk->e = e; - sk->p = p; - sk->q = q; - sk->d = d; - sk->u = u; - - /* now we can test our keys (this should never fail!) */ - test_keys( sk, nbits - 64 ); -} - - -/**************** - * Test wether the secret key is valid. - * Returns: true if this is a valid key. - */ -static int -check_secret_key( RSA_secret_key *sk ) -{ - int rc; - MPI temp = mpi_alloc( mpi_get_nlimbs(sk->p)*2 ); - - mpi_mul(temp, sk->p, sk->q ); - rc = mpi_cmp( temp, sk->n ); - mpi_free(temp); - return !rc; -} - - - -/**************** - * Public key operation. Encrypt INPUT with PKEY and put result into OUTPUT. - * - * c = m^e mod n - * - * Where c is OUTPUT, m is INPUT and e,n are elements of PKEY. - */ -static void -public(MPI output, MPI input, RSA_public_key *pkey ) -{ - if( output == input ) { /* powm doesn't like output and input the same */ - MPI x = mpi_alloc( mpi_get_nlimbs(input)*2 ); - mpi_powm( x, input, pkey->e, pkey->n ); - mpi_set(output, x); - mpi_free(x); - } - else - mpi_powm( output, input, pkey->e, pkey->n ); -} - -#if 0 -static void -stronger_key_check ( RSA_secret_key *skey ) -{ - MPI t = mpi_alloc_secure ( 0 ); - MPI t1 = mpi_alloc_secure ( 0 ); - MPI t2 = mpi_alloc_secure ( 0 ); - MPI phi = mpi_alloc_secure ( 0 ); - - /* check that n == p * q */ - mpi_mul( t, skey->p, skey->q); - if (mpi_cmp( t, skey->n) ) - log_info ( "RSA Oops: n != p * q\n" ); - - /* check that p is less than q */ - if( mpi_cmp( skey->p, skey->q ) > 0 ) - log_info ("RSA Oops: p >= q\n"); - - - /* check that e divides neither p-1 nor q-1 */ - mpi_sub_ui(t, skey->p, 1 ); - mpi_fdiv_r(t, t, skey->e ); - if ( !mpi_cmp_ui( t, 0) ) - log_info ( "RSA Oops: e divides p-1\n" ); - mpi_sub_ui(t, skey->q, 1 ); - mpi_fdiv_r(t, t, skey->e ); - if ( !mpi_cmp_ui( t, 0) ) - log_info ( "RSA Oops: e divides q-1\n" ); - - /* check that d is correct */ - mpi_sub_ui( t1, skey->p, 1 ); - mpi_sub_ui( t2, skey->q, 1 ); - mpi_mul( phi, t1, t2 ); - mpi_gcd(t, t1, t2); - mpi_fdiv_q(t, phi, t); - mpi_invm(t, skey->e, t ); - if ( mpi_cmp(t, skey->d ) ) - log_info ( "RSA Oops: d is wrong\n"); - - /* check for crrectness of u */ - mpi_invm(t, skey->p, skey->q ); - if ( mpi_cmp(t, skey->u ) ) - log_info ( "RSA Oops: u is wrong\n"); - - log_info ( "RSA secret key check finished\n"); - - mpi_free (t); - mpi_free (t1); - mpi_free (t2); - mpi_free (phi); -} -#endif - - - -/**************** - * Secret key operation. Encrypt INPUT with SKEY and put result into OUTPUT. - * - * m = c^d mod n - * - * Or faster: - * - * m1 = c ^ (d mod (p-1)) mod p - * m2 = c ^ (d mod (q-1)) mod q - * h = u * (m2 - m1) mod q - * m = m1 + h * p - * - * Where m is OUTPUT, c is INPUT and d,n,p,q,u are elements of SKEY. - */ -static void -secret(MPI output, MPI input, RSA_secret_key *skey ) -{ - #if 0 - mpi_powm( output, input, skey->d, skey->n ); - #else - MPI m1 = mpi_alloc_secure( mpi_get_nlimbs(skey->n)+1 ); - MPI m2 = mpi_alloc_secure( mpi_get_nlimbs(skey->n)+1 ); - MPI h = mpi_alloc_secure( mpi_get_nlimbs(skey->n)+1 ); - - /* m1 = c ^ (d mod (p-1)) mod p */ - mpi_sub_ui( h, skey->p, 1 ); - mpi_fdiv_r( h, skey->d, h ); - mpi_powm( m1, input, h, skey->p ); - /* m2 = c ^ (d mod (q-1)) mod q */ - mpi_sub_ui( h, skey->q, 1 ); - mpi_fdiv_r( h, skey->d, h ); - mpi_powm( m2, input, h, skey->q ); - /* h = u * ( m2 - m1 ) mod q */ - mpi_sub( h, m2, m1 ); - if ( mpi_is_neg( h ) ) - mpi_add ( h, h, skey->q ); - mpi_mulm( h, skey->u, h, skey->q ); - /* m = m2 + h * p */ - mpi_mul ( h, h, skey->p ); - mpi_add ( output, m1, h ); - /* ready */ - - mpi_free ( h ); - mpi_free ( m1 ); - mpi_free ( m2 ); - #endif -} - - - -/********************************************* - ************** interface ****************** - *********************************************/ - -int -rsa_generate( int algo, unsigned nbits, MPI *skey, MPI **retfactors ) -{ - RSA_secret_key sk; - - if( !is_RSA(algo) ) - return GCRYERR_INV_PK_ALGO; - - generate( &sk, nbits ); - skey[0] = sk.n; - skey[1] = sk.e; - skey[2] = sk.d; - skey[3] = sk.p; - skey[4] = sk.q; - skey[5] = sk.u; - /* make an empty list of factors */ - *retfactors = g10_xcalloc( 1, sizeof **retfactors ); - return 0; -} - - -int -rsa_check_secret_key( int algo, MPI *skey ) -{ - RSA_secret_key sk; - - if( !is_RSA(algo) ) - return GCRYERR_INV_PK_ALGO; - - sk.n = skey[0]; - sk.e = skey[1]; - sk.d = skey[2]; - sk.p = skey[3]; - sk.q = skey[4]; - sk.u = skey[5]; - if( !check_secret_key( &sk ) ) - return GCRYERR_INV_PK_ALGO; - - return 0; -} - - - -int -rsa_encrypt( int algo, MPI *resarr, MPI data, MPI *pkey ) -{ - RSA_public_key pk; - - if( algo != 1 && algo != 2 ) - return GCRYERR_INV_PK_ALGO; - - pk.n = pkey[0]; - pk.e = pkey[1]; - resarr[0] = mpi_alloc( mpi_get_nlimbs( pk.n ) ); - public( resarr[0], data, &pk ); - return 0; -} - -int -rsa_decrypt( int algo, MPI *result, MPI *data, MPI *skey ) -{ - RSA_secret_key sk; - - if( algo != 1 && algo != 2 ) - return GCRYERR_INV_PK_ALGO; - - sk.n = skey[0]; - sk.e = skey[1]; - sk.d = skey[2]; - sk.p = skey[3]; - sk.q = skey[4]; - sk.u = skey[5]; - *result = mpi_alloc_secure( mpi_get_nlimbs( sk.n ) ); - secret( *result, data[0], &sk ); - return 0; -} - -int -rsa_sign( int algo, MPI *resarr, MPI data, MPI *skey ) -{ - RSA_secret_key sk; - - if( algo != 1 && algo != 3 ) - return GCRYERR_INV_PK_ALGO; - - sk.n = skey[0]; - sk.e = skey[1]; - sk.d = skey[2]; - sk.p = skey[3]; - sk.q = skey[4]; - sk.u = skey[5]; - resarr[0] = mpi_alloc( mpi_get_nlimbs( sk.n ) ); - secret( resarr[0], data, &sk ); - - return 0; -} - -int -rsa_verify( int algo, MPI hash, MPI *data, MPI *pkey, - int (*cmp)(void *opaque, MPI tmp), void *opaquev ) -{ - RSA_public_key pk; - MPI result; - int rc; - - if( algo != 1 && algo != 3 ) - return GCRYERR_INV_PK_ALGO; - pk.n = pkey[0]; - pk.e = pkey[1]; - result = gcry_mpi_new ( 160 ); - public( result, data[0], &pk ); - /*rc = (*cmp)( opaquev, result );*/ - rc = mpi_cmp( result, hash )? GCRYERR_BAD_SIGNATURE:0; - gcry_mpi_release (result); - - return rc; -} - - -unsigned int -rsa_get_nbits( int algo, MPI *pkey ) -{ - if( !is_RSA(algo) ) - return 0; - return mpi_get_nbits( pkey[0] ); -} - - -/**************** - * Return some information about the algorithm. We need algo here to - * distinguish different flavors of the algorithm. - * Returns: A pointer to string describing the algorithm or NULL if - * the ALGO is invalid. - * Usage: Bit 0 set : allows signing - * 1 set : allows encryption - */ -const char * -rsa_get_info( int algo, - int *npkey, int *nskey, int *nenc, int *nsig, int *usage ) -{ - *npkey = 2; - *nskey = 6; - *nenc = 1; - *nsig = 1; - - switch( algo ) { - case 1: *usage = GCRY_PK_USAGE_SIGN | GCRY_PK_USAGE_ENCR; return "RSA"; - case 2: *usage = GCRY_PK_USAGE_ENCR; return "RSA-E"; - case 3: *usage = GCRY_PK_USAGE_SIGN; return "RSA-S"; - default:*usage = 0; return NULL; - } -} - - - - - - - |