diff options
Diffstat (limited to 'cipher/ecc.c')
| -rw-r--r-- | cipher/ecc.c | 3199 |
1 files changed, 1730 insertions, 1469 deletions
diff --git a/cipher/ecc.c b/cipher/ecc.c index b2e08478..14fff812 100644 --- a/cipher/ecc.c +++ b/cipher/ecc.c @@ -1,5 +1,5 @@ /* ecc.c - ECElGamal Public Key encryption & ECDSA signature algorithm - * Copyright (C) 2004, 2005, 2006 Free Software Foundation, Inc. + * Copyright (C) 2004, 2005, 2006, 2007 Free Software Foundation, Inc. * * This file is part of GnuPG. * @@ -15,9 +15,17 @@ * * 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 + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, + * USA. */ +/* TODO wk + + - Check whether we can LGPL the code. + + +*/ + /* This code is a based on the * Patch 0.1.6 for the gnupg 1.4.x branch * as retrieved on 2007-03-21 from @@ -45,7 +53,7 @@ * more polite gen_k() and its calls. * mmr: extend the check_secret_key() * In process: - * genBigPoint(): Randomize the point generation. + * gen_big_point(): Randomize the point generation. * improve te memory uses. * Separation between sign & encrypt keys to facility the subkeys creation. * read & reread the code in a bug search! @@ -58,1355 +66,1560 @@ #include <stdio.h> #include <stdlib.h> #include <string.h> -#include "types.h" -#include "util.h" + +#include "g10lib.h" #include "mpi.h" #include "cipher.h" -#include "ecc.h" - -//ECC over F_p; E(F_p) -//T=(p,a,b,G,n,h) -// p: big odd number -// a,b: curve generators -// G: Subgroup generator point -// n: big int, in G order -// h: cofactor -// y^2=x^3+ax+b --> (Y^2)Z=X^3+aX(Z^2)+b(Z^3) - -// -// Q=[d]G, 1<=d<=n-1 - -typedef struct { - MPI x_; - MPI y_; - MPI z_; -} point; //Point representation in projective coordinates. - -typedef struct { - MPI p_; - MPI a_,b_; - //MPI Gx,Gy,Gz; - point G; - MPI n_; - //MPI h_; =1 //!! We will need to change this value in 2-isogeny -} ellipticCurve;//doubtful name //!! - -typedef struct { - ellipticCurve E; - point Q; /*Q=[d]G*/ -} ECC_public_key;//Q - -typedef struct { - ellipticCurve E; - point Q; /*Q=[d]G*/ - MPI d; -} ECC_secret_key;//d - - -static MPI gen_k( MPI p, int secure ); - -static void generateCurve(unsigned nbits, ellipticCurve *ECC_curve);//choice a curve of the rank - -static void generateKey(ECC_secret_key *sk, unsigned nbits , MPI **factors );//Generate de cryptosystem setup. -static void testKeys( ECC_secret_key *sk, unsigned nbits );//verify correct skey -static int check_secret_key( ECC_secret_key *sk );//check the validity of the value -static void doEncrypt(MPI input, ECC_public_key *pkey, point *R, MPI c); -static MPI decrypt(MPI output, ECC_secret_key *skey, point R, MPI c); -static void sign(MPI input, ECC_secret_key *skey, MPI *r, MPI *s); -static int verify(MPI input, ECC_public_key *pkey, MPI r, MPI s); - -static int genBigPoint(MPI *prime, ellipticCurve *base, point *G, unsigned nbits);//return -1 if it isn't possible -static point genPoint(MPI prime, ellipticCurve base);//random point over an Elliptic curve -static MPI existSquareRoot(MPI integer, MPI modulus);//return true or false -static void Lucas(MPI n, MPI p_, MPI q_, MPI k, MPI V_n, MPI Q_0); - -static int PointAtInfinity(point Query);//return true(1), false(0), or error(-1) for an invalid point - -static void escalarMult(MPI escalar, point *P, point *R, ellipticCurve *base);//return R=escalarP -static void sumPoints(point *P0, point *P1, point *P2, ellipticCurve *base);//P2=P0+P1 -static void duplicatePoint(point *P, point *R, ellipticCurve *base);//R=2P -static void invertPoint(point *P, ellipticCurve *base);//P=-P - -static point point_copy(point P); -static void point_free(point *P); -static int point_affine(point *P, MPI x, MPI y, ellipticCurve *base);//turn an projective coordinate to affine, return 0 (1 if error). -static ellipticCurve curve_copy(ellipticCurve E); -static void curve_free(ellipticCurve *E); -static MPI gen_bit(); -static MPI gen_y_2(MPI x, ellipticCurve *base); - -//Function for IFP ECElGamal Weakness. -static void sha256_hashing(MPI input, MPI *output);//Compute a hash -static void aes256_encrypting(MPI key, MPI input, MPI *output);//Encrypt simmetricaly -static void aes256_decrypting(MPI key, MPI input, MPI *output);//Decrypt simmetricaly - -static void (*progress_cb) ( void *, int ); -static void *progress_cb_data; -static void -progress( int c ) +/* + ECC over F_p; E(F_p) + T=(p,a,b,G,n,h) + p: big odd number + a,b: curve generators + G: Subgroup generator point + n: big int, in G order + h: cofactor + y^2=x^3+ax+b --> (Y^2)Z=X^3+aX(Z^2)+b(Z^3) + + + Q=[d]G, 1<=d<=n-1 +*/ + + +/* Point representation in projective coordinates. */ +typedef struct { - if ( progress_cb ) - progress_cb ( progress_cb_data, c ); - else - fputc( c, stderr ); -} + gcry_mpi_t x_; + gcry_mpi_t y_; + gcry_mpi_t z_; +} point_t; -/**************** - * At the begging was the same than elgamal.c - * but mmr improve it. - * Generate a random secret scalar k with an order of p - * Moreover it do NOT use Wiener's table. - */ -static MPI -gen_k( MPI p, int secure ){ - - MPI k = mpi_alloc_secure( 0 ); - unsigned int nbits = mpi_get_nbits(p); - unsigned int nbytes; - - nbytes = (nbits+7)/8; - if( DBG_CIPHER ) - log_debug("choosing a random k of %u bits\n", nbits); - char *c = get_random_bits( nbits, secure, 1 ); - mpi_set_buffer( k, c, nbytes, 0 ); - xfree(c); - mpi_fdiv_r(k,k, p);//simple module: k=k (mod p) - if( DBG_CIPHER ) - progress('\n'); - - return k; -} -/**************** - * Generate de cryptosystem setup. - * At this time it fix the values to the ones which NIST recomend. - * The subgroup generator point is in another function: 'genBigPoint'. - */ -static void -generateCurve(unsigned nbits, ellipticCurve *ECC_curve){ - - ellipticCurve E; - //point *G; - - if( nbits == 192 ){//NIST P-192 - E.p_ =mpi_alloc((nbits/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.p_,\ - "0xfffffffffffffffffffffffffffffffeffffffffffffffff")) - log_fatal("ECC operation: Curve assigments failed(p)\n"); - else ECC_curve->p_ = mpi_copy(E.p_); - E.a_ =mpi_alloc((2/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.a_,\ - "0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFFFFFFFFFC"))//"-0x3")) - log_fatal("ECC operation: Curve assigments failed(a)\n"); - else ECC_curve->a_ = mpi_copy(E.a_); - E.b_ =mpi_alloc((nbits/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.b_,\ - "0x64210519e59c80e70fa7e9ab72243049feb8deecc146b9b1")) - log_fatal("ECC operation: Curve assigments failed(b)\n"); - else ECC_curve->b_ = mpi_copy(E.b_); - E.n_ =mpi_alloc((nbits/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.n_,\ - "0xffffffffffffffffffffffff99def836146bc9b1b4d22831")) - log_fatal("ECC operation: Curve assigments failed(n)\n"); - else ECC_curve->n_ = mpi_copy(E.n_); - } - else if( nbits == 224 ){//NIST P-224 - E.p_ =mpi_alloc((nbits/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.p_,\ - "0xffffffffffffffffffffffffffffffff000000000000000000000001")) - log_fatal("ECC operation: Curve assigments failed(p)\n"); - else ECC_curve->p_ = mpi_copy(E.p_); - E.a_ =mpi_alloc((2/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.a_,\ - "0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFE"))//"-0x3")) - log_fatal("ECC operation: Curve assigments failed(a)\n"); - else ECC_curve->a_ = mpi_copy(E.a_); - E.b_ =mpi_alloc((nbits/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.b_,\ - "0xb4050a850c04b3abf54132565044b0b7d7bfd8ba270b39432355ffb4")) - log_fatal("ECC operation: Curve assigments failed(b)\n"); - else ECC_curve->b_ = mpi_copy(E.b_); - E.n_ =mpi_alloc((nbits/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.n_,\ - "0xffffffffffffffffffffffffffff16a2e0b8f03e13dd29455c5c2a3d")) - log_fatal("ECC operation: Curve assigments failed(n)\n"); - else ECC_curve->n_ = mpi_copy(E.n_); - } - else if( nbits == 256 ){//NIST P-256 - E.p_ =mpi_alloc((nbits/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.p_,\ - "0xffffffff00000001000000000000000000000000ffffffffffffffffffffffff")) - log_fatal("ECC operation: Curve assigments failed(p)\n"); - else ECC_curve->p_ = mpi_copy(E.p_); - E.a_ =mpi_alloc((2/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.a_,\ - "0xFFFFFFFF00000001000000000000000000000000FFFFFFFFFFFFFFFFFFFFFFFC"))//"-0x3")) - log_fatal("ECC operation: Curve assigments failed(a)\n"); - else ECC_curve->a_ = mpi_copy(E.a_); - E.b_ =mpi_alloc((nbits/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.b_,\ - "0x5ac635d8aa3a93e7b3ebbd55769886bc651d06b0cc53b0f63bce3c3e27d2604b")) - log_fatal("ECC operation: Curve assigments failed(b)\n"); - else ECC_curve->b_ = mpi_copy(E.b_); - E.n_ =mpi_alloc((nbits/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.n_,\ - "0xffffffff00000000ffffffffffffffffbce6faada7179e84f3b9cac2fc632551")) - log_fatal("ECC operation: Curve assigments failed(n)\n"); - else ECC_curve->n_ = mpi_copy(E.n_); - } - else if( nbits == 384 ){//NIST P-384 - E.p_ =mpi_alloc((nbits/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.p_,\ - "0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffeffffffff0000000000000000ffffffff")) - log_fatal("ECC operation: Curve assigments failed(p)\n"); - else ECC_curve->p_ = mpi_copy(E.p_); - E.a_ =mpi_alloc((2/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.a_,\ - "0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFF0000000000000000FFFFFFFC"))//"-0x3")) - log_fatal("ECC operation: Curve assigments failed(a)\n"); - else ECC_curve->a_ = mpi_copy(E.a_); - E.b_ =mpi_alloc((nbits/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.b_,\ - "0xb3312fa7e23ee7e4988e056be3f82d19181d9c6efe8141120314088f5013875ac656398d8a2ed19d2a85c8edd3ec2aef")) - log_fatal("ECC operation: Curve assigments failed(b)\n"); - else ECC_curve->b_ = mpi_copy(E.b_); - E.n_ =mpi_alloc((nbits/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.n_,\ - "0xffffffffffffffffffffffffffffffffffffffffffffffffc7634d81f4372ddf581a0db248b0a77aecec196accc52973")) - log_fatal("ECC operation: Curve assigments failed(n)\n"); - else ECC_curve->n_ = mpi_copy(E.n_); - } - else if( nbits == 521 ){//NIST P-521 - E.p_ =mpi_alloc((nbits/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.p_,\ - "0x1ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff")) - log_fatal("ECC operation: Curve assigments failed(p)\n"); - else ECC_curve->p_ = mpi_copy(E.p_); - E.a_ =mpi_alloc((2/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.a_,\ - "0x1FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFC"))//"-0x3")) - log_fatal("ECC operation: Curve assigments failed(a)\n"); - else ECC_curve->a_ = mpi_copy(E.a_); - E.b_ =mpi_alloc((nbits/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.b_,\ - "0x051953eb9618e1c9a1f929a21a0b68540eea2da725b99b315f3b8b489918ef109e156193951ec7e937b1652c0bd3bb1bf073573df883d2c34f1ef451fd46b503f00")) - log_fatal("ECC operation: Curve assigments failed(b)\n"); - else ECC_curve->b_ = mpi_copy(E.b_); - E.n_ =mpi_alloc((nbits/(BYTES_PER_MPI_LIMB*8))+1); - if (mpi_fromstr(E.n_,\ - "0x1fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffa51868783bf2f966b7fcc0148f709a5d03bb5c9b8899c47aebb6fb71e91386409")) - log_fatal("ECC operation: Curve assigments failed(n)\n"); - else ECC_curve->n_ = mpi_copy(E.n_); - } - else{ - log_fatal("ECC operation: Curve generation failed\n"); - } - if( DBG_CIPHER ){ - progress('\n'); - log_mpidump("generation p= ", ECC_curve->p_ ); - log_mpidump("generation a= ", ECC_curve->a_ ); - log_mpidump("generation b= ", ECC_curve->b_ ); - log_mpidump("generation n= ", ECC_curve->n_ ); - } - if ( genBigPoint(&ECC_curve->n_, ECC_curve, &ECC_curve->G, nbits) == -1){ - log_fatal("ECC operation: Point generation failed\n"); - } - if( DBG_CIPHER ) { - log_mpidump("generation Gx= ", ECC_curve->G.x_ ); - log_mpidump("generation Gy= ", ECC_curve->G.y_ ); - log_mpidump("generation Gz= ", ECC_curve->G.z_ ); - log_info("Setup generated\n"); - progress('\n'); - } -} +/* Definition of a curve. */ +typedef struct +{ + gcry_mpi_t p_; /* Prime specifying the field GF(p). */ + gcry_mpi_t a_; /* First coefficient of the Weierstrass equation. */ + gcry_mpi_t b_; /* Second coefficient of teh Weierstrass equation. */ + point_t G; /* Base point (generator). */ + gcry_mpi_t n_; /* Order of G. */ + /*gcry_mpi_t h_; =1 fixme: We will need to change this value in 2-isogeny */ +} elliptic_curve_t; /* Fixme: doubtful name */ -/**************** - * Fisrt obtain the setup. - * Over the finite field randomize an scalar secret value, and calculat de public point. - * - * !! What about the **ret_factors !! //!! - */ -static void -generateKey(ECC_secret_key *sk, unsigned nbits , MPI **ret_factors ){ - ellipticCurve E; - MPI d; - point Q,G; +typedef struct +{ + elliptic_curve_t E; + point_t Q; /* Q=[d]G */ +} ECC_public_key; /* Q */ - generateCurve(nbits,&E); +typedef struct +{ + elliptic_curve_t E; + point_t Q; /* Q=[d]G */ + gcry_mpi_t d; +} ECC_secret_key; /* d */ - d = mpi_alloc_secure(nbits/BITS_PER_MPI_LIMB); - if( DBG_CIPHER ) - log_debug("choosing a random x of size %u\n", nbits ); - d = gen_k(E.n_,2);//generate_secret_prime(nbits); - G = point_copy(E.G); - escalarMult(d,&E.G,&Q,&E); +/* This static table defines all available curves. */ +static const struct +{ + const char *desc; /* Description of the curve. */ + unsigned int nbits; /* Number of bits. */ + const char *p, *a, *b, *n; /* Parameters. */ + const char *g_x, *g_y; /* G_z is always 1. */ +} domain_parms[] = + { + { + "NIST P-192", 192, + "0xfffffffffffffffffffffffffffffffeffffffffffffffff", + "0xfffffffffffffffffffffffffffffffefffffffffffffffc", + "0x64210519e59c80e70fa7e9ab72243049feb8deecc146b9b1", + "0xffffffffffffffffffffffff99def836146bc9b1b4d22831", + + "0x188da80eb03090f67cbf20eb43a18800f4ff0afd82ff1012", + "0x07192b95ffc8da78631011ed6b24cdd573f977a11e794811" + }, + { + "NIST P-224", 224, + "0xffffffffffffffffffffffffffffffff000000000000000000000001", + "0xfffffffffffffffffffffffffffffffefffffffffffffffffffffffe", + "0xb4050a850c04b3abf54132565044b0b7d7bfd8ba270b39432355ffb4", + "0xffffffffffffffffffffffffffff16a2e0b8f03e13dd29455c5c2a3d" , + + "0xb70e0cbd6bb4bf7f321390b94a03c1d356c21122343280d6115c1d21", + "0xbd376388b5f723fb4c22dfe6cd4375a05a07476444d5819985007e34" + }, + { + "NIST P-256", 256, + "0xffffffff00000001000000000000000000000000ffffffffffffffffffffffff", + "0xffffffff00000001000000000000000000000000fffffffffffffffffffffffc", + "0x5ac635d8aa3a93e7b3ebbd55769886bc651d06b0cc53b0f63bce3c3e27d2604b", + "0xffffffff00000000ffffffffffffffffbce6faada7179e84f3b9cac2fc632551", + + "0x6b17d1f2e12c4247f8bce6e563a440f277037d812deb33a0f4a13945d898c296", + "0x4fe342e2fe1a7f9b8ee7eb4a7c0f9e162bce33576b315ececbb6406837bf51f5" + }, + { + "NIST P-384", 384, + "0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffe" + "ffffffff0000000000000000ffffffff", + "0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffe" + "ffffffff0000000000000000fffffffc", + "0xb3312fa7e23ee7e4988e056be3f82d19181d9c6efe8141120314088f5013875a" + "c656398d8a2ed19d2a85c8edd3ec2aef", + "0xffffffffffffffffffffffffffffffffffffffffffffffffc7634d81f4372ddf" + "581a0db248b0a77aecec196accc52973", + + "0xaa87ca22be8b05378eb1c71ef320ad746e1d3b628ba79b9859f741e082542a38" + "5502f25dbf55296c3a545e3872760ab7", + "0x3617de4a96262c6f5d9e98bf9292dc29f8f41dbd289a147ce9da3113b5f0b8c0" + "0a60b1ce1d7e819d7a431d7c90ea0e5f" + }, + { + "NIST P-521", 521, + "0x01ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff" + "ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff", + "0x01ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff" + "fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffc", + "0x051953eb9618e1c9a1f929a21a0b68540eea2da725b99b315f3b8b489918ef10" + "9e156193951ec7e937b1652c0bd3bb1bf073573df883d2c34f1ef451fd46b503f00", + "0x1fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff" + "ffa51868783bf2f966b7fcc0148f709a5d03bb5c9b8899c47aebb6fb71e91386409", + + "0xc6858e06b70404e9cd9e3ecb662395b4429c648139053fb521f828af606b4d3d" + "baa14b5e77efe75928fe1dc127a2ffa8de3348b3c1856a429bf97e7e31c2e5bd66", + "0x11839296a789a3bc0045c8a5fb42c7d1bd998f54449579b446817afbd17273e6" + "62c97ee72995ef42640c550b9013fad0761353c7086a272c24088be94769fd16650" + }, + { NULL, 0, NULL, NULL, NULL, NULL } + }; + + +/* Registered progress function and its callback value. */ +static void (*progress_cb) (void *, const char*, int, int, int); +static void *progress_cb_data; - /* copy the stuff to the key structures */ - sk->E.p_ = mpi_copy(E.p_); - sk->E.a_ = mpi_copy(E.a_); - sk->E.b_ = mpi_copy(E.b_); - sk->E.G = point_copy(E.G); - sk->E.n_ = mpi_copy(E.n_); - sk->Q = point_copy(Q); - sk->d = mpi_copy(d); - /* now we can test our keys (this should never fail!) */ - testKeys( sk, nbits - 64 ); - point_free(&Q); - mpi_free(d); - curve_free(&E); -} + +/* Local prototypes. */ +static gcry_mpi_t gen_k (gcry_mpi_t p, int secure); +static void test_keys (ECC_secret_key * sk, unsigned int nbits); +static int check_secret_key (ECC_secret_key * sk); +static void sign (gcry_mpi_t input, ECC_secret_key * skey, gcry_mpi_t * r, gcry_mpi_t * s); +static int verify (gcry_mpi_t input, ECC_public_key * pkey, gcry_mpi_t r, gcry_mpi_t s); -/**************** - * To verify correct skey it use a random information. - * First, encrypt and decrypt this dummy value, - * test if the information is recuperated. - * Second, test with the sign and verify functions. - */ -static void -testKeys( ECC_secret_key *sk, unsigned nbits ){ - ECC_public_key pk; - MPI test = mpi_alloc( nbits / BITS_PER_MPI_LIMB ); - point R_; - MPI c = mpi_alloc( nbits / BITS_PER_MPI_LIMB ); - MPI out = mpi_alloc( nbits / BITS_PER_MPI_LIMB ); - MPI r = mpi_alloc( nbits / BITS_PER_MPI_LIMB ); - MPI s = mpi_alloc( nbits / BITS_PER_MPI_LIMB ); +static int point_at_infinity (point_t query); - if( DBG_CIPHER )log_info("Testing key.\n"); +static gcry_mpi_t gen_y_2 (gcry_mpi_t x, elliptic_curve_t * base); - pk.E = curve_copy(sk->E); - pk.E.G = point_copy(sk->E.G); - pk.Q = point_copy(sk->Q); - /*mpi_set_bytes( test, nbits, get_random_byte, 0 );*/ - { char *p = get_random_bits( nbits, 0, 0 ); - mpi_set_buffer( test, p, (nbits+7)/8, 0 ); - xfree(p); - } - doEncrypt(test,&pk,&R_,c); + +void +_gcry_register_pk_ecc_progress (void (*cb) (void *, const char *, + int, int, int), + void *cb_data) +{ + progress_cb = cb; + progress_cb_data = cb_data; +} - out = decrypt(out,sk,R_,c); +static void +progress (int c) +{ + if (progress_cb) + progress_cb (progress_cb_data, "pk_dsa", c, 0, 0); + else + fputc (c, stderr); +} - if( mpi_cmp( test, out ) )//test!=out - log_fatal("ECELG operation: encrypt, decrypt failed\n"); - if( DBG_CIPHER )log_info("ECELG operation: encrypt, decrypt ok.\n"); - sign(test,sk,&r,&s); + +/* - if( !verify(test,&pk,r,s) ){ - log_fatal("ECDSA operation: sign, verify failed\n");} + O B J E C T M A I N T E N A N C E - if( DBG_CIPHER )log_info("ECDSA operation: sign, verify ok.\n"); + */ - mpi_free(s); - mpi_free(r); - mpi_free(out); - mpi_free(c); - point_free(&R_); - mpi_free(test); +/* Intialize a point object, so that its elements may be sued directly + as MPI functions. point_free is required for each initialzied + point. */ +static void +point_init (point_t *P) +{ + P->x_ = mpi_new (0); + P->y_ = mpi_new (0); + P->z_ = mpi_new (0); } -/**************** - * To check the validity of the value, recalculate the correspondence - * between the public value and de secret one. - */ -static int -check_secret_key( ECC_secret_key *sk ){ - - point Q; - MPI y_2,y2 = mpi_alloc(0); - - //?primarity test of 'p' - // (...) //!! - //G in E(F_p) - y_2 = gen_y_2(sk->E.G.x_,&sk->E);// y^2=x^3+a*x+b - mpi_mulm(y2,sk->E.G.y_,sk->E.G.y_,sk->E.p_);// y^2=y*y - if (mpi_cmp(y_2,y2)){ - if( DBG_CIPHER )log_info("Bad check: Point 'G' does not belong to curve 'E'!\n"); - return (1); - } - //G != PaI - if (PointAtInfinity(sk->E.G)){ - if( DBG_CIPHER )log_info("Bad check: 'G' cannot be Point at Infinity!\n"); - return (1); - } - //?primarity test of 'n' - // (...) //!! - //?(p-sqrt(p)) < n < (p+sqrt(p)) - //?n!=p - //?(n^k) mod p !=1 for k=1 to 31 (from GOST) or k=1 to 50 (from MIRACL) - //Q=[n]G over E = PaI - escalarMult(sk->E.n_,&sk->E.G,&Q,&sk->E); - if (!PointAtInfinity(Q)){ - if( DBG_CIPHER )log_info("Bad check: 'E' is not curve of order 'n'!\n"); - return (1); - } - //pubkey cannot be PaI - if (PointAtInfinity(sk->Q)){ - if( DBG_CIPHER )log_info("Bad check: Q can not be a Point at Infinity!\n"); - return (1); - } - //pubkey = [d]G over E - escalarMult(sk->d,&sk->E.G,&Q,&sk->E); - if ((Q.x_ == sk->Q.x_) && (Q.y_ == sk->Q.y_) && (Q.z_ == sk->Q.z_)){ - if( DBG_CIPHER )log_info("Bad check: There is NO correspondence between 'd' and 'Q'!\n"); - return (1); - } - point_free(&Q); - return (0); -} -/**************** - * Encrypt a number and obtain and struct (R,c) +/* + * Release a point object. */ static void -doEncrypt(MPI input, ECC_public_key *pkey, point *R, MPI c){ - - MPI k,p,x,y; - point P,Q,G; - ellipticCurve E; - - k = mpi_alloc(0); - p = mpi_copy(pkey->E.p_); - x = mpi_alloc(0); - y = mpi_alloc(0); - Q = point_copy(pkey->Q); - G = point_copy(pkey->E.G); - E = curve_copy(pkey->E); - - k = gen_k( p, 1);//2nd parametre: how much security? - escalarMult(k,&Q,&P,&E);//P=[k]Q=[k]([d]G) - escalarMult(k,&G,R,&E);//R=[k]G - //IFP weakness//mpi_mul(c,input,Q.x_);//c=input*Q_x - //MMR Use affine conversion befor extract x-coordinate - if (point_affine(&P,x,y,&E)){//Q cannot turn to affine coordinate - if( DBG_CIPHER ){log_info("Encrypting: Cannot turn to affine.\n");} - } - //MMR According to the standard P1363 we can not use x-coordinate directly. - // It is necessary to add hash-operation later. - // As the maximal length of a key for the symmetric cipher is 256 bit it is possible to take hash-function SHA256. - sha256_hashing(x,&x); - aes256_encrypting(x,input,&c); - - if( DBG_CIPHER ){log_debug("doEncrypt: end.\n");} +point_free (point_t *P) +{ + mpi_free (P->x_); P->x_ = NULL; + mpi_free (P->y_); P->y_ = NULL; + mpi_free (P->z_); P->z_ = NULL; } -/**************** - * Undo the ciphertext + +/* + * Return a copy of a point object. */ -static MPI -decrypt(MPI output, ECC_secret_key *skey, point R, MPI c){ - - MPI p,inv,x,y; - point P,Q; - ellipticCurve E; - - p = mpi_copy(skey->E.p_); - inv = mpi_alloc(0); - x = mpi_alloc(0); - y = mpi_alloc(0); - Q = point_copy(skey->Q); - E = curve_copy(skey->E); - - escalarMult(skey->d,&R,&P,&E);//P=[d]R - //That is like: mpi_fdiv_q(output,c,Q.x_); - //IFP weakness//mpi_invm(inv,Q.x_,p);//inv=Q{_x}^-1 (mod p) - //IFP weakness//mpi_mulm(output,c,inv,p);//output=c*inv (mod p) - //MMR Use affine conversion befor extract x-coordinate - if (point_affine(&P,x,y,&E)){//Q cannot turn to affine coordinate - if( DBG_CIPHER ){log_info("Encrypting: Cannot turn to affine.\n");} - } - sha256_hashing(x,&x); - aes256_decrypting(x,c,&output); - - if( DBG_CIPHER ){log_debug("decrypt: end.\n");} - return (output); +static point_t +point_copy (point_t P) +{ + point_t R; + + R.x_ = mpi_copy (P.x_); + R.y_ = mpi_copy (P.y_); + R.z_ = mpi_copy (P.z_); + + return R; } -/**************** - * Return the signature struct (r,s) from the message hash. + +/* + * Release a curve object. */ static void -sign(MPI input, ECC_secret_key *skey, MPI *r, MPI *s){ - - MPI k,i,dr,sum,k_1,x,y; - point G,I; - ellipticCurve E; - - k = mpi_alloc(0); i = mpi_alloc(0); dr = mpi_alloc(0); sum = mpi_alloc(0); k_1 = mpi_alloc(0); - x = mpi_alloc(0); y = mpi_alloc(0); - G = point_copy(skey->E.G); - E = curve_copy(skey->E); - *r = mpi_alloc(0); - *s = mpi_alloc(0); - - while (!mpi_cmp_ui(*s,0)){//s==0 - while (!mpi_cmp_ui(*r,0)){//r==0 - k = gen_k( E.p_, 1 ); - escalarMult(k,&G,&I,&E);//I=[k]G - if (point_affine(&I,x,y,&E)){//I cannot turn to affine coordinate - if( DBG_CIPHER ){log_info("Sign: Cannot turn to affine. Cannot complete sign.\n");} - } - i = mpi_copy(x);//i=I_x - mpi_fdiv_r(*r,i,E.n_);//simple module: r=i (mod n) - } - mpi_mulm(dr,skey->d,*r,E.n_);//dr=d*r (mod n) - mpi_addm(sum,input,dr,E.n_);//sum=hash+(d*r) (mod n) - mpi_invm(k_1,k,E.n_);//k_1=k^(-1) (mod n) - mpi_mulm(*s,k_1,sum,E.n_);// s=k^(-1)*(hash+(d*r)) (mod n) - } - if( DBG_CIPHER ){log_debug("Sign: end\n");} - mpi_free(y); - mpi_free(x); - mpi_free(k_1); - mpi_free(sum); - mpi_free(dr); - mpi_free(i); - mpi_free(k); +curve_free (elliptic_curve_t *E) +{ + mpi_free (E->p_); E->p_ = NULL; + mpi_free (E->a_); E->a_ = NULL; + mpi_free (E->b_); E->b_ = NULL; + point_free (&E->G); + mpi_free (E->n_); E->n_ = NULL; } -/**************** - * Check if the struct (r,s) is for the hash value that it have. - */ -static int -verify(MPI input, ECC_public_key *pkey, MPI r, MPI s){ - - MPI r_,s_,h,h1,h2,i,x,y; - point Q,Q1,Q2,G; - ellipticCurve E; - - r_ = mpi_alloc(0); s_ = mpi_alloc(0); h = mpi_alloc(0); h1 = mpi_alloc(0); h2 = mpi_alloc(0); x = mpi_alloc(0); y = mpi_alloc(0); - G = point_copy(pkey->E.G); - E = curve_copy(pkey->E); - - mpi_fdiv_r(r_,r,pkey->E.n_);//simple module - mpi_fdiv_r(s_,s,pkey->E.n_);//simple module - - //check if the input parameters are valid. - if ( mpi_cmp(r_,r) || mpi_cmp(s_,s)) {//r_!=r || s_!=s - if( DBG_CIPHER ){log_info("Verification: No valid values.\n");} - return 0; //not valid values. - } - - mpi_invm(h,s,E.n_);//h=s^(-1) (mod n) - mpi_mulm(h1,input,h,E.n_);//h1=hash*s^(-1) (mod n) - escalarMult(h1,&G,&Q1,&E);//Q1=[hash*s^(-1)]G - mpi_mulm(h2,r,h,E.n_);//h2=r*s^(-1) (mod n) - escalarMult(h2,&pkey->Q,&Q2,&E);//Q2=[r*s^(-1)]Q - sumPoints(&Q1,&Q2,&Q,&E);//Q=([hash*s^(-1)]G)+([r*s^(-1)]Q) - - if (PointAtInfinity(Q)){ - if( DBG_CIPHER ){log_info("Verification: Rejected.\n");} - return 0;//rejected - } - if (point_affine(&Q,x,y,&E)){//Q cannot turn to affine coordinate - if( DBG_CIPHER ){log_info("Verification: Cannot turn to affine. Rejected.\n");} - return 0;//rejected - } - i = mpi_copy(x);//Give the x_coordinate - mpi_fdiv_r(i,i,E.n_);//simple module - - if (!mpi_cmp(i,r)){//i==r => Return 0 (distance between them). - if( DBG_CIPHER ){log_info("Verification: Accepted.\n");} - return 1;//accepted - } - if( DBG_CIPHER ){log_info("Verification: Not verified.\n");} - return 0; -} -/**************** - * A point of order 'n' is needed to generate a ciclic subgroup. - * Over this ciclic subgroup it's defined the ECDLP. - * Now it use a fix values from NIST FIPS PUB 186-2. +/* + * Return a copy of a curve object. */ -static int -genBigPoint(MPI *prime, ellipticCurve *base, point *G, unsigned nbits){ - ///*estandard nist - if( nbits == 192 ){//NIST P-192 - G->x_ = mpi_alloc(mpi_get_nlimbs(base->n_)); - if (mpi_fromstr(G->x_,\ - "0x188da80eb03090f67cbf20eb43a18800f4ff0afd82ff1012")) - log_fatal("Generator operation: Point assigments failed(x)\n"); - G->y_ = mpi_alloc(mpi_get_nlimbs(base->n_)); - if (mpi_fromstr(G->y_,\ - "0x07192b95ffc8da78631011ed6b24cdd573f977a11e794811")) - log_fatal("Generator operation: Point assigments failed(y)\n"); - G->z_ = mpi_alloc_set_ui(1); - } - else if( nbits == 224 ){//NIST P-224 - G->x_ = mpi_alloc(mpi_get_nlimbs(base->n_)); - if (mpi_fromstr(G->x_,\ - "0xb70e0cbd6bb4bf7f321390b94a03c1d356c21122343280d6115c1d21")) - log_fatal("Generator operation: Point assigments failed(x)\n"); - G->y_ = mpi_alloc(mpi_get_nlimbs(base->n_)); - if (mpi_fromstr(G->y_,\ - "0xbd376388b5f723fb4c22dfe6cd4375a05a07476444d5819985007e34")) - log_fatal("Generator operation: Point assigments failed(y)\n"); - G->z_ = mpi_alloc_set_ui(1); - } - else if( nbits == 256 ){//NIST P-256 - G->x_ = mpi_alloc(mpi_get_nlimbs(base->n_)); - if (mpi_fromstr(G->x_,\ - "0x6b17d1f2e12c4247f8bce6e563a440f277037d812deb33a0f4a13945d898c296")) - log_fatal("Generator operation: Point assigments failed(x)\n"); - G->y_ = mpi_alloc(mpi_get_nlimbs(base->n_)); - if (mpi_fromstr(G->y_,\ - "0x4fe342e2fe1a7f9b8ee7eb4a7c0f9e162bce33576b315ececbb6406837bf51f5")) - log_fatal("Generator operation: Point assigments failed(y)\n"); - G->z_ = mpi_alloc_set_ui(1); - } - else if( nbits == 384 ){//NIST P-384 - G->x_ = mpi_alloc(mpi_get_nlimbs(base->n_)); - if (mpi_fromstr(G->x_,\ - "0xaa87ca22be8b05378eb1c71ef320ad746e1d3b628ba79b9859f741e082542a385502f25dbf55296c3a545e3872760ab7")) - log_fatal("Generator operation: Point assigments failed(x)\n"); - G->y_ = mpi_alloc(mpi_get_nlimbs(base->n_)); - if (mpi_fromstr(G->y_,\ - "0x3617de4a96262c6f5d9e98bf9292dc29f8f41dbd289a147ce9da3113b5f0b8c00a60b1ce1d7e819d7a431d7c90ea0e5f")) - log_fatal("Generator operation: Point assigments failed(y)\n"); - G->z_ = mpi_alloc_set_ui(1); - } - else if( nbits == 521 ){//NIST P-521 - G->x_ = mpi_alloc(mpi_get_nlimbs(base->n_)); - if (mpi_fromstr(G->x_,\ - "0xc6858e06b70404e9cd9e3ecb662395b4429c648139053fb521f828af606b4d3dbaa14b5e77efe75928fe1dc127a2ffa8de3348b3c1856a429bf97e7e31c2e5bd66")) - log_fatal("Generator operation: Point assigments failed(x)\n"); - G->y_ = mpi_alloc(mpi_get_nlimbs(base->n_)); - if (mpi_fromstr(G->y_,\ - "0x11839296a789a3bc0045c8a5fb42c7d1bd998f54449579b446817afbd17273e662c97ee72995ef42640c550b9013fad0761353c7086a272c24088be94769fd16650")) - log_fatal("Generator operation: Point assigments failed(y)\n"); - G->z_ = mpi_alloc_set_ui(1); - } - //end Estandard nist - /*Randomize G - unsigned int i=0; - MPI one; - point Big, P; - - one = mpi_alloc_set_ui(1); - G->x_ = mpi_alloc(mpi_get_nlimbs(*prime)); - G->y_ = mpi_alloc(mpi_get_nlimbs(*prime)); - G->z_ = mpi_alloc(mpi_get_nlimbs(*prime)); - - if( DBG_MPI )log_info("Generating a Big point.\n"); - do{ - do{ - *P = genPoint(*prime,*base); - }while(PointAtInfinity(*P));//A random point in the curve that it's not PaI - escalarMult(base.h,&P,&G,&base);//cofactor (1 o 2), could be improved - }while(PointAtInfinity(G)); - if( DBG_MPI )log_info("Big point generated.\n"); - if( DBG_MPI ){ - log_mpidump("Gx=",G->x_);log_mpidump("Gy=",G->y_);log_mpidump("Gz=",G->z_); - } - return 0; - *///end aleatoritzar G - return 0; +static elliptic_curve_t +curve_copy (elliptic_curve_t E) +{ + elliptic_curve_t R; + + R.p_ = mpi_copy (E.p_); + R.a_ = mpi_copy (E.a_); + R.b_ = mpi_copy (E.b_); + R.G = point_copy (E.G); + R.n_ = mpi_copy (E.n_); + + return R; } -/**************** - * Generate a random point over an Elliptic curve - * is the first step to find a random ciclic subgroup - * generator. - * - * !! At this moment it isn't used !! //!! + + +/* + + A D D I T I O N A L M P I F U N C T I O N S + */ -static point -genPoint(MPI prime, ellipticCurve base){ - - unsigned int i=0; - MPI x,y_2,y; - MPI one, one_neg,bit; - point P; - - x = mpi_alloc(mpi_get_nlimbs(base.p_)); - y_2 = mpi_alloc(mpi_get_nlimbs(base.p_)); - y = mpi_alloc(mpi_get_nlimbs(base.p_)); - one = mpi_alloc_set_ui(1); - one_neg = mpi_alloc(mpi_get_nlimbs(one)); - mpi_invm(one_neg,one,base.p_); - - if( DBG_MPI )log_info("Generating a normal point.\n"); - do{ - x = gen_k(base.p_,1);//generate_public_prime(mpi_get_nlimbs(base.n_)*BITS_PER_MPI_LIMB); - do{ - y_2 = gen_y_2(x,&base);//x^3+ax+b (mod p) - mpi_add_ui(x, x, 1); - i++; - }while( !mpi_cmp_ui(y_2,0) && i<0xf);//Try to find a valid value until 16 iterations. - i=0; - y = existSquareRoot(y_2,base.p_); - }while( !mpi_cmp_ui(y,0));//Repeat until a valid coordinate is found. - bit = gen_bit();//generate one bit - if (mpi_cmp_ui(bit,1)){//choose the y coordinate - mpi_invm(y, y, base.p_);//mpi_powm(y, y, one_neg,base.p_); - } - if( DBG_MPI )log_info("Normal point generated.\n"); - - P.x_ = mpi_copy(x); - P.y_ = mpi_copy(y); - P.z_ = mpi_copy(one); - - mpi_free(bit); - mpi_free(one_neg); - mpi_free(one); - mpi_free(y); - mpi_free(y_2); - mpi_free(x); - - return(P); -} + /**************** - * Find, if it exist, the square root of one integer module a big prime. - * Return the square root or 0 if it is not found. + * Find, if it exist, the square root of one integer modulo a big prime. + * Return the square root or NULL if it is not found. */ -static MPI -existSquareRoot(MPI integer, MPI modulus){ - - unsigned long int i=0; - MPI one,two,three,four,five,eight; - MPI k,r,z,k1; - MPI t1,t2,t3,t4; - - one = mpi_alloc_set_ui(1); - two = mpi_alloc_set_ui(2); - three = mpi_alloc_set_ui(3); - four = mpi_alloc_set_ui(4); - five = mpi_alloc_set_ui(5); - eight = mpi_alloc_set_ui(8); - k = mpi_alloc(mpi_get_nlimbs(modulus)); - r = mpi_alloc(mpi_get_nlimbs(modulus)); - z = mpi_alloc(mpi_get_nlimbs(modulus)); - k1 = mpi_alloc(mpi_get_nlimbs(modulus)); - t1 = mpi_alloc(mpi_get_nlimbs(modulus)); - t2 = mpi_alloc(mpi_get_nlimbs(modulus)); - t3 = mpi_alloc(mpi_get_nlimbs(modulus)); - t4 = mpi_alloc(mpi_get_nlimbs(modulus)); - - if( DBG_MPI )log_mpidump("?exist Square Root of ",integer); - - mpi_fdiv_qr(k,r,modulus,four); - if (mpi_cmp(r,three)){//p=3 (mod 4) - mpi_addm(k1,k,one,modulus); - mpi_powm(z,integer,k1,modulus); - if( DBG_MPI ){log_mpidump("z=",z);} - return z;//value found - } - mpi_fdiv_qr(k,r,modulus,eight); - if (mpi_cmp(r,five)){//p=5 (mod 8) - mpi_mulm(t1,two,integer,modulus); - mpi_powm(t2,t1,k,modulus); - mpi_powm(t2,t2,two,modulus); - mpi_mulm(t2,t1,t2,modulus); - mpi_mulm(t3,integer,t1,modulus); - mpi_subm(t4,t2,one,modulus); - mpi_mulm(z,t3,t4,modulus); - if( DBG_MPI ){log_mpidump("z=",z);} - return z;//value found - } - if (mpi_cmp(r,one)){//p=1 (mod 8) - while(i<0xFF){//while not find z after 256 iterations*/ - if( DBG_MPI )log_info("Square root bucle.\n"); - t1 = mpi_copy(integer); - t2 = gen_k(modulus,0); - mpi_add_ui(t3,modulus,1);//t3=p+1 - mpi_rshift(t3,t3,1);//t3=t3/2 - Lucas(t1,t2,t3,modulus,t4,t3);//t4=V_k - mpi_rshift(z,t4,1);//z=V/2 - mpi_sub_ui(t3,modulus,1);//t3=p-1 - mpi_rshift(t4,t3,2);//t4=t3/2 - Lucas(t1,t2,t4,modulus,t4,t1);//t1=Q_0 - mpi_powm(t2,z,two,modulus);//t2=z^2 - if (mpi_cmp(t1,integer)){ - if( DBG_MPI ){log_mpidump("z=",z);} - return z;//value found - } - if (t4>mpi_alloc_set_ui(1) && t4<t3){ - if( DBG_MPI )log_info("Rejected.\n"); - return (0); //NULL - } - if( DBG_MPI )log_info("Another loop.\n"); - } - } - if( DBG_MPI )log_info("iterations limit.\n"); - return (0);//because this algorithm not always finish. +#if 0 +static gcry_mpi_t +exist_square_root (gcry_mpi_t integer, gcry_mpi_t modulus) +{ + unsigned long int i = 0; + gcry_mpi_t one, two, three, four, five, eight; + gcry_mpi_t k, r, z, k1; + gcry_mpi_t t1, t2, t3, t4; + + one = mpi_alloc_set_ui (1); + two = mpi_alloc_set_ui (2); + three = mpi_alloc_set_ui (3); + four = mpi_alloc_set_ui (4); + five = mpi_alloc_set_ui (5); + eight = mpi_alloc_set_ui (8); + k = mpi_alloc (mpi_get_nlimbs (modulus)); + r = mpi_alloc (mpi_get_nlimbs (modulus)); + z = mpi_alloc (mpi_get_nlimbs (modulus)); + k1 = mpi_alloc (mpi_get_nlimbs (modulus)); + t1 = mpi_alloc (mpi_get_nlimbs (modulus)); + t2 = mpi_alloc (mpi_get_nlimbs (modulus)); + t3 = mpi_alloc (mpi_get_nlimbs (modulus)); + t4 = mpi_alloc (mpi_get_nlimbs (modulus)); + + if (DBG_CIPHER) + log_mpidump ("?exist Square Root of ", integer); + + mpi_fdiv_qr (k, r, modulus, four); + if (mpi_cmp (r, three)) + { /* p=3 (mod 4) */ + mpi_addm (k1, k, one, modulus); + mpi_powm (z, integer, k1, modulus); + if (DBG_CIPHER) + { + log_mpidump ("z=", z); + } + return z; /* value found */ + } + mpi_fdiv_qr (k, r, modulus, eight); + if (mpi_cmp (r, five)) + { /* p=5 (mod 8) */ + mpi_mulm (t1, two, integer, modulus); + mpi_powm (t2, t1, k, modulus); + mpi_powm (t2, t2, two, modulus); + mpi_mulm (t2, t1, t2, modulus); + mpi_mulm (t3, integer, t1, modulus); + mpi_subm (t4, t2, one, modulus); + mpi_mulm (z, t3, t4, modulus); + if (DBG_CIPHER) + { + log_mpidump ("z=", z); + } + return z; /* value found */ + } + if (mpi_cmp (r, one)) + { /* p=1 (mod 8) */ + while (i < 0xFF) + { /* while not find z after 256 iterations */ + if (DBG_CIPHER) + log_debug ("Square root bucle.\n"); + t1 = mpi_copy (integer); + t2 = gen_k (modulus, 0); + mpi_add_ui (t3, modulus, 1); /* t3=p+1 */ + mpi_rshift (t3, t3, 1); /* t3=t3/2 */ + lucas (t1, t2, t3, modulus, t4, t3); /* t4=V_k */ + mpi_rshift (z, t4, 1); /* z=V/2 */ + mpi_sub_ui (t3, modulus, 1); /* t3=p-1 */ + mpi_rshift (t4, t3, 2); /* t4=t3/2 */ + lucas (t1, t2, t4, modulus, t4, t1); /* t1=Q_0 */ + mpi_powm (t2, z, two, modulus); /* t2=z^2 */ + if (mpi_cmp (t1, integer)) + { + if (DBG_CIPHER) + { + log_mpidump ("z=", z); + } + return z; /* value found */ + } + if (t4 > mpi_alloc_set_ui (1) && t4 < t3) + { + if (DBG_CIPHER) + log_debug ("Rejected.\n"); + return (0); /* NULL */ + } + if (DBG_CIPHER) + log_debug ("Another loop.\n"); + } + } + if (DBG_CIPHER) + log_debug ("iterations limit.\n"); + return (0); /* because this algorithm not always finish. */ } +#endif /*0*/ /**************** * Formal definition: - * V_0=2;V_1=p - * V_k=(p*V_(k-1))-(q*V_(k-2)) for k>=2 + * V_0 = 2; V_1 = p + * V_k = (p*V_(k-1)) - (q*V_(k-2)) for k >= 2 */ +#if 0 static void -Lucas(MPI n, MPI p_, MPI q_, MPI k, MPI V_n, MPI Q_0){ - - MPI v0,v1,q0,q1; - MPI t1,t2; - unsigned int r,i; - - v0 = mpi_alloc_set_ui(2); - v1 = mpi_copy(p_); - q0 = mpi_alloc_set_ui(1); - q1 = mpi_alloc_set_ui(1); - t1 = mpi_alloc_set_ui(0); - t2 = mpi_alloc_set_ui(0); - - if( DBG_MPI ){log_info("Generating lucas sequence.\n");log_mpidump("k=",k);} - - r = mpi_get_nbits(k)-1; - i = 0; - while (mpi_test_bit(k,i) != 1){ //search the first bit with value '1' - i++; - } - while (i<r){ - if( DBG_MPI ){ - log_info("Lucas sequence bucle.\n"); - log_mpidump("i=",mpi_alloc_set_ui(i)); - log_mpidump("r=",mpi_alloc_set_ui(r)); - } - mpi_mulm(q0,q0,q1,n); - if (mpi_test_bit(k,i) == 1){ - mpi_mulm(q1,q0,q_,n); - mpi_mul(t1,v0,v1); - mpi_mul(t2,p_,q0); - mpi_subm(v0,t1,t2,n); - mpi_powm(t1,v1,mpi_alloc_set_ui(2),n); - mpi_mul(t2,mpi_alloc_set_ui(2),q1); - mpi_subm(v1,t1,t2,n); - } - else{ - q1 = mpi_copy(q0); - mpi_mul(t1,v0,v1); - mpi_mul(t2,p_,q0); - mpi_subm(v1,t1,t2,n); - mpi_powm(t1,v0,mpi_alloc_set_ui(2),n); - mpi_mul(t2,mpi_alloc_set_ui(2),q0); - mpi_subm(v0,t1,t2,n); - } - i++; - } - V_n = mpi_copy(v0); - Q_0 = mpi_copy(q0); - if( DBG_MPI ){ - log_info("Lucas sequence generated.\n"); - log_mpidump("V_n=",V_n); - log_mpidump("Q_0=",Q_0); - } +lucas (gcry_mpi_t n, gcry_mpi_t p_, gcry_mpi_t q_, + gcry_mpi_t k, gcry_mpi_t V_n, gcry_mpi_t Q_0) +{ + + gcry_mpi_t v0, v1, q0, q1; + gcry_mpi_t t1, t2; + unsigned int r, i; + + v0 = mpi_alloc_set_ui (2); + v1 = mpi_copy (p_); + q0 = mpi_alloc_set_ui (1); + q1 = mpi_alloc_set_ui (1); + t1 = mpi_alloc_set_ui (0); + t2 = mpi_alloc_set_ui (0); + + if (DBG_CIPHER) + { + log_debug ("Generating lucas sequence.\n"); + log_mpidump ("k=", k); + } + + r = mpi_get_nbits (k) - 1; + i = 0; + while (mpi_test_bit (k, i) != 1) + { /* search the first bit with value '1' */ + i++; + } + while (i < r) + { + if (DBG_CIPHER) + { + log_debug ("Lucas sequence bucle.\n"); + log_mpidump ("i=", mpi_alloc_set_ui (i)); + log_mpidump ("r=", mpi_alloc_set_ui (r)); + } + mpi_mulm (q0, q0, q1, n); + if (mpi_test_bit (k, i) == 1) + { + mpi_mulm (q1, q0, q_, n); + mpi_mul (t1, v0, v1); + mpi_mul (t2, p_, q0); + mpi_subm (v0, t1, t2, n); + mpi_powm (t1, v1, mpi_alloc_set_ui (2), n); + mpi_mul (t2, mpi_alloc_set_ui (2), q1); + mpi_subm (v1, t1, t2, n); + } + else + { + q1 = mpi_copy (q0); + mpi_mul (t1, v0, v1); + mpi_mul (t2, p_, q0); + mpi_subm (v1, t1, t2, n); + mpi_powm (t1, v0, mpi_alloc_set_ui (2), n); + mpi_mul (t2, mpi_alloc_set_ui (2), q0); + mpi_subm (v0, t1, t2, n); + } + i++; + } + V_n = mpi_copy (v0); + Q_0 = mpi_copy (q0); + if (DBG_CIPHER) + { + log_debug ("Lucas sequence generated.\n"); + log_mpidump ("V_n=", V_n); + log_mpidump ("Q_0=", Q_0); + } } +#endif /*0*/ -/**************** + +/* + + P O I N T A N D C U R V E O P E R A T I O N S + + */ + +/* fixme: * The point at infinity is needed to make * a group structure to the elliptic curve. * Know if one point is it, is needed so * much times in this code. + * + * return true(1), false(0), or error(-1) for an invalid point */ static int -PointAtInfinity(point Query){ - - if( DBG_MPI ){log_info("?is a Point at Infinity.\n");} - - if (!mpi_cmp_ui(Query.z_,0)){//Z=0 - if (/*mpi_cmp_ui(Query.x_,0) && */mpi_cmp_ui(Query.y_,0)){//X & Y!=0 & Z=0 - if( DBG_MPI )log_info("True:It is a Point at Infinite.\n"); - return (1); //true - } - if( DBG_MPI )log_info("Error:It isn't an elliptic curve valid point.\n"); - return (-1); // - } - if( DBG_MPI ){log_info("False:It isn't a Point at Infinity.\n");} - return (0); //it is a valid curve point, but it isn't the point at infinity +point_at_infinity (point_t query) +{ + if (!mpi_cmp_ui (query.z_, 0)) /* Z == 0 */ + { + if ( /*mpi_cmp_ui(Query.x_,0) && */ mpi_cmp_ui (query.y_, 0)) + { + /* X && Y != 0 & Z == 0 */ + /* Fixme: The above condition is not asserted. We may get + to here if X is 0 ! */ + if (DBG_CIPHER) + log_debug ("True:It is a Point at Infinite.\n"); + return 1; + } + if (DBG_CIPHER) + log_debug ("Error:It isn't an elliptic curve valid point.\n"); + return -1; + } + return 0; /* It is a valid curve point, but not the point at infinity. */ } -/**************** - * The modular power used without EC, - * is this function over EC. + +/* + * Turn a projective coordinate to affine, return 0 (or 1 in error case). + * Returns 0 on success. + * + * Note, that Y is never used as we can do without it. */ -static void -escalarMult(MPI escalar, point *P, point *R, ellipticCurve *base){ - - MPI one,two,three; - MPI p; - MPI xx,yy,zz,x1,y1,z1,z2,z3,k,h;//it could use less memory!!!! - unsigned int i,loops; - point P1,P2,P1_; - - x1 = mpi_alloc(mpi_get_nlimbs(P->x_)); - y1 = mpi_alloc(mpi_get_nlimbs(P->y_)); - z2 = mpi_alloc(mpi_get_nlimbs(P->z_)); - z3 = mpi_alloc(mpi_get_nlimbs(P->z_)); - h = mpi_alloc(mpi_get_nlimbs(P->z_)); - - if( DBG_MPI )log_info("Calculating an scalar Multiple.\n"); - - one = mpi_alloc_set_ui(1); - two = mpi_alloc_set_ui(2); - three = mpi_alloc_set_ui(3); - p = mpi_copy(base->p_); - - if ( !mpi_cmp_ui(escalar,0) || mpi_cmp_ui(P->z_,0)){//n=0 | Z=0 => [1:1:0] - R->x_ = mpi_copy(one); - R->y_ = mpi_copy(one); - R->z_ = mpi_alloc(0); - } - xx = mpi_copy(P->x_); - zz = mpi_copy(P->z_); - z1 = mpi_copy(one); - if (mpi_is_neg(escalar)){//(-n)P=n(-P) - escalar->sign = 0;//+n - k = mpi_copy(escalar); - yy = mpi_copy(P->y_);//-P - mpi_invm(yy,yy,p); - } - else { - k = mpi_copy(escalar); - yy = mpi_copy(P->y_); - } - if (!mpi_cmp(zz,one)){//zz==1 - x1 = mpi_copy(xx); - y1 = mpi_copy(yy); - } - else { - mpi_mulm(z2,zz,zz,p);//z^2 - mpi_mulm(z3,zz,z2,p);//z^3 - mpi_invm(z2,z2,p);//1/Z^2 - mpi_mulm(x1,xx,z2,p);//xx/z^2 - mpi_invm(z3,z3,p);//1/z^3 - mpi_mulm(y1,yy,z3,p);//yy/z^3 - } - mpi_mul(h,three,k);//h=3k - loops = mpi_get_nbits(h); - i=loops-2; // i = l-1 = loops-2 - R->x_ = mpi_copy(xx); - R->y_ = mpi_copy(yy); - R->z_ = mpi_copy(zz); - P1.x_ = mpi_copy(x1); - P1.y_ = mpi_copy(y1); - P1.z_ = mpi_copy(z1); - while(i>0){ // A.10.9. step 11 i from l-1 downto 1 - duplicatePoint(R,R,base); - if ( mpi_test_bit(h,i) == 1 && mpi_test_bit(k,i) == 0){//h_i=1 & k_i=0 - P2 = point_copy(*R); - sumPoints(&P2,&P1,R,base);//R=P2+P1 over the base elliptic curve - } - if ( mpi_test_bit(h,i) == 0 && mpi_test_bit(k,i) == 1){//h_i=0 & k_i=1 - P2 = point_copy(*R); - P1_ = point_copy(P1); - invertPoint(&P1_,base); - sumPoints(&P2,&P1_,R,base);//R=P2+P1_ over the base elliptic curve - } - i--; - } - if( DBG_MPI )log_info("Scalar Multiple calculated.\n"); - - point_free(&P1); - point_free(&P2); - point_free(&P1_); - mpi_free(h); - mpi_free(k); - mpi_free(z3); - mpi_free(z2); - mpi_free(z1); - mpi_free(y1); - mpi_free(x1); - mpi_free(zz); - mpi_free(yy); - mpi_free(xx); - mpi_free(p); - mpi_free(three); - mpi_free(two); - mpi_free(one); +static int +point_affine (point_t *P, gcry_mpi_t x, gcry_mpi_t y, elliptic_curve_t *base) +{ + gcry_mpi_t z1, z2, z3; + + z1 = mpi_new (0); + z2 = mpi_new (0); + z3 = mpi_new (0); + + if (point_at_infinity (*P)) + { + if (DBG_CIPHER) + log_debug ("ecc point_affine: " + "Point at Infinity does NOT exist in the affine plane!\n"); + return 1; + } + + mpi_invm (z1, P->z_, base->p_); /* z1 =Z^{-1} (mod p) */ + mpi_mulm (z2, z1, z1, base->p_); /* z2 =Z^(-2) (mod p) */ + mpi_mulm (z3, z2, z1, base->p_); /* z3 =Z^(-3) (mod p) */ + mpi_mulm (x, P->x_, z2, base->p_); + mpi_mulm (y, P->y_, z3, base->p_); + + mpi_free (z1); + mpi_free (z2); + mpi_free (z3); + return 0; } -/**************** - * Point addition is the group operation. + +/* + * The point inversion over F_p is a simple modular inversion of the Y + * coordinate. */ static void -sumPoints(point *P0, point *P1, point *P2, ellipticCurve *base){ - - MPI one,two; - MPI p; - MPI t1,t2,t3,t4,t5,t6,t7; - - one = mpi_alloc_set_ui(1); - two = mpi_alloc_set_ui(2); - p = mpi_copy(base->p_); - t1 = mpi_alloc(mpi_get_nlimbs(p)); - t2 = mpi_alloc(mpi_get_nlimbs(p)); - t3 = mpi_alloc(mpi_get_nlimbs(p)); - t4 = mpi_alloc(mpi_get_nlimbs(p)); - t5 = mpi_alloc(mpi_get_nlimbs(p)); - t6 = mpi_alloc(mpi_get_nlimbs(p)); - t7 = mpi_alloc(mpi_get_nlimbs(p)); - - if( DBG_MPI )log_info("Add two points.\n"); - - if ((!mpi_cmp(P1->x_,P0->x_)) && (!mpi_cmp(P1->y_,P0->y_)) && (!mpi_cmp(P1->z_,P0->z_))){// P1=P0 - duplicatePoint(P0,P2,base); - } - else if (PointAtInfinity(*P0)){//(!mpi_cmp_ui(P0->y_,0) || !mpi_cmp_ui(P0->z_,0)){// P2=0+P1=P1 - P2->x_ = mpi_copy(P1->x_); - P2->y_ = mpi_copy(P1->y_); - P2->z_ = mpi_copy(P1->z_); - } - else if (PointAtInfinity(*P1)){//(!mpi_cmp_ui(P1->y_,0) || !mpi_cmp_ui(P1->z_,0)){// P2=P0+0=P0 - P2->x_ = mpi_copy(P0->x_); - P2->y_ = mpi_copy(P0->y_); - P2->z_ = mpi_copy(P0->z_); - } - else { - t1 = mpi_copy(P0->x_);//t1=x0 - t2 = mpi_copy(P0->y_);//t2=y0 - t3 = mpi_copy(P0->z_);//t3=z0 - t4 = mpi_copy(P1->x_);//t4=x1 - t5 = mpi_copy(P1->y_);//t5=y2 - if (mpi_cmp(P1->z_,one)){//z1!=1 - t6 = mpi_copy(P1->z_);//t6=z1 - mpi_powm(t7, t6,two,p);//t7=t6^2 mod p - mpi_mulm(t1,t1,t7,p);//t1=t1*t7 mod p - mpi_mulm(t7,t6,t7,p);//t7=t6*t7 mod p - mpi_mulm(t2,t2,t7,p);//t2=t2*t7 mod p - } - mpi_powm(t7,t3,two,p);//t7=t3^2 mod p - mpi_mulm(t4,t4,t7,p);//t4=t4*t7 mod p - mpi_mulm(t7,t3,t7,p);//t7=t3*t7 mod p - mpi_mulm(t5,t5,t7,p);//t5=t5*t7 mod p - mpi_subm(t4,t1,t4,p);//t4=t1-t4 mod p - mpi_subm(t5,t2,t5,p);//t5=t2-t5 mod p - if (!mpi_cmp_ui(t4,0)){//t4==0 - if (!mpi_cmp_ui(t5,0)){//return (0:0:0), it have an special mean. - if( DBG_MPI )log_info("Point Addition: [0:0:0]!\n"); - P2->x_ = mpi_copy(mpi_alloc_set_ui(0)); - P2->y_ = mpi_copy(mpi_alloc_set_ui(0)); - P2->z_ = mpi_copy(mpi_alloc_set_ui(0)); - } - else {//return (1:1:0) - if( DBG_MPI )log_info("Point Addition: [1:1:0]!\n"); - P2->x_ = mpi_copy(one); - P2->y_ = mpi_copy(one); - P2->z_ = mpi_copy(mpi_alloc_set_ui(0)); - } - } - else{ - mpi_mulm(t1,two,t1,p); - mpi_subm(t1,t1,t4,p);//t1=2*t1-t4 mod p - mpi_mulm(t2,two,t2,p); - mpi_subm(t2,t2,t5,p);//t2=2*t2-t5 mod p - if (mpi_cmp(P1->z_,one)){//z1!=1 - mpi_mulm(t3,t3,t6,p);//t3=t3*t6 - } - mpi_mulm(t3,t3,t4,p);//t3=t3*t4 mod p - mpi_powm(t7,t4,two,p);//t7=t4^2 mod p - mpi_mulm(t4,t4,t7,p);//t4=t4*t7 mod p - mpi_mulm(t7,t1,t7,p);//t7=t1*t7 mod p - mpi_powm(t1,t5,two,p);//t1=t5^2 mod p - mpi_subm(t1,t1,t7,p);//t1=t1-t7 mod p - mpi_mulm(t6,two,t1,p); - mpi_subm(t7,t7,t6,p);//t7=t7-2*t1 mod p - mpi_mulm(t5,t5,t7,p);//t5=t5*t7 mod p - mpi_mulm(t4,t2,t4,p);//t4=t2*t4 mod p - mpi_subm(t2,t5,t4,p);//t2=t5-t4 mod p - mpi_invm(t6,two,p); - mpi_mulm(t2,t2,t6,p);//t2 = t2/2 - - P2->x_ = mpi_copy(t1); - P2->y_ = mpi_copy(t2); - P2->z_ = mpi_copy(t3); - } - } - mpi_free(t7); - mpi_free(t6); - mpi_free(t5); - mpi_free(t4); - mpi_free(t3); - mpi_free(t2); - mpi_free(t1); - mpi_free(p); - mpi_free(two); - mpi_free(one); +invert_point (point_t *P, elliptic_curve_t *base) +{ + mpi_subm (P->y_, base->p_, P->y_, base->p_); /* y = p - y mod p */ } -/**************** + +/* * Scalar multiplication of one point, with the integer fixed to 2. + * R = 2P */ static void -duplicatePoint(point *P, point *R, ellipticCurve *base){ - - MPI one,two,three,four,eight; - MPI p,p_3,a; - MPI t1,t2,t3,t4,t5,t6,t7; - MPI aux; - - one = mpi_alloc_set_ui(1); - two = mpi_alloc_set_ui(2); - three = mpi_alloc_set_ui(3); - four = mpi_alloc_set_ui(4); - eight = mpi_alloc_set_ui(8); - p = mpi_copy(base->p_); - p_3 = mpi_alloc(mpi_get_nlimbs(p)); - mpi_sub_ui(p_3,p,3); - a = mpi_copy(base->a_); - t1 = mpi_alloc(mpi_get_nlimbs(p)); - t2 = mpi_alloc(mpi_get_nlimbs(p)); - t3 = mpi_alloc(mpi_get_nlimbs(p)); - t4 = mpi_alloc(mpi_get_nlimbs(p)); - t5 = mpi_alloc(mpi_get_nlimbs(p)); - t6 = mpi_alloc(mpi_get_nlimbs(p)); - t7 = mpi_alloc(mpi_get_nlimbs(p)); - aux= mpi_alloc(mpi_get_nlimbs(p)); - - if( DBG_MPI ){log_info("Duplicate a point.\n");} - - t1 = mpi_copy(P->x_);//t1=x1 - t2 = mpi_copy(P->y_);//t2=y1 - t3 = mpi_copy(P->z_);//t3=z1 - - if (!mpi_cmp_ui(t2,0) || !mpi_cmp_ui(t3,0)){//t2==0 | t3==0 => [1:1:0] - if( DBG_MPI ){log_info("t2==0 | t3==0\n");} - R->x_ = mpi_copy(one); - R->y_ = mpi_copy(one); - R->z_ = mpi_copy(mpi_alloc_set_ui(0)); - } - else{ - mpi_fdiv_r(a,a,p);//a mod p - if (!mpi_cmp(a,p_3)){//a==p-3 - mpi_powm(t4,t3,two,p);//t4=t3^2 mod p - mpi_subm(t5,t1,t4,p);//t5=t1-t4 mod p - mpi_addm(t4,t1,t4,p);//t4=t1+t4 mod p - mpi_mulm(t5,t4,t5,p);//t5=t4*t5 mod p - mpi_mulm(t4,three,t5,p);//t4=3*t5 mod p - } - else{ - t4 = mpi_copy(a);//t4=a - mpi_powm(t5,t3,two,p);//t5=t3^2 mod p - mpi_powm(t5,t5,two,p);//t5=t5^2 mod p - mpi_mulm(t5,t4,t5,p);//t5=t4*t5 mod p - mpi_powm(t4,t1,two,p);//t4=t1^2 mod p - mpi_mulm(t4,three,t4,p);//t4=3*t4 mod p - mpi_addm(t4,t4,t5,p);//t4=t4+t5 mod p - } - if( DBG_MPI ){log_info("t2!=0 & t3!=0\n");} - mpi_mulm(t3,t2,t3,p);//t3=t2*t3 mod p - mpi_mulm(t3,two,t3,p);//t3=2*t3 mod p - mpi_powm(aux,t2,two,p);//t2=t2^2 mod p - t2 = mpi_copy(aux); - mpi_mulm(t5,t1,t2,p);//t5=t1*t2 mod p - mpi_mulm(t5,four,t5,p);//t5=4*t5 mod p - mpi_powm(t1,t4,two,p);//t1=t4^2 mod p - mpi_mulm(aux,two,t5,p); - mpi_subm(t1,t1,aux,p);//t1=t1-2*t5 mod p - mpi_powm(aux,t2,two,p);//t2=t2^2 mod p - t2 = mpi_copy(aux); - mpi_mulm(t2,eight,t2,p);//t2=8*t2 mod p - mpi_subm(t5,t5,t1,p);//t5=t5-t1 mod p - mpi_mulm(t5,t4,t5,p);//t5=t4*t5 mod p - mpi_subm(t2,t5,t2,p);//t2=t5-t2 mod p - - R->x_ = mpi_copy(t1); - R->y_ = mpi_copy(t2); - R->z_ = mpi_copy(t3); - } - if( DBG_MPI ){log_info("Duplicated point.\n");} - - mpi_free(aux); - mpi_free(t7); - mpi_free(t6); - mpi_free(t5); - mpi_free(t4); - mpi_free(t3); - mpi_free(t2); - mpi_free(t1); - mpi_free(p); - mpi_free(p_3); - mpi_free(a); - mpi_free(eight); - mpi_free(four); - mpi_free(three); - mpi_free(two); - mpi_free(one); +duplicate_point (point_t *R, point_t *P, elliptic_curve_t * base) +{ + gcry_mpi_t one, two, three, four, eight; + gcry_mpi_t p, p_3, a; + gcry_mpi_t t1, t2, t3, t4, t5, t6, t7; + gcry_mpi_t aux; + + one = mpi_alloc_set_ui (1); + two = mpi_alloc_set_ui (2); + three = mpi_alloc_set_ui (3); + four = mpi_alloc_set_ui (4); + eight = mpi_alloc_set_ui (8); + p = mpi_copy (base->p_); + p_3 = mpi_alloc (mpi_get_nlimbs (p)); + mpi_sub_ui (p_3, p, 3); + a = mpi_copy (base->a_); + t1 = mpi_alloc (mpi_get_nlimbs (p)); + t2 = mpi_alloc (mpi_get_nlimbs (p)); + t3 = mpi_alloc (mpi_get_nlimbs (p)); + t4 = mpi_alloc (mpi_get_nlimbs (p)); + t5 = mpi_alloc (mpi_get_nlimbs (p)); + t6 = mpi_alloc (mpi_get_nlimbs (p)); + t7 = mpi_alloc (mpi_get_nlimbs (p)); + aux = mpi_alloc (mpi_get_nlimbs (p)); + + t1 = mpi_copy (P->x_); /* t1=x1 */ + t2 = mpi_copy (P->y_); /* t2=y1 */ + t3 = mpi_copy (P->z_); /* t3=z1 */ + + if (!mpi_cmp_ui (t2, 0) || !mpi_cmp_ui (t3, 0)) + { /* t2==0 | t3==0 => [1:1:0] */ + mpi_set_ui (R->x_, 1); + mpi_set_ui (R->y_, 1); + mpi_set_ui (R->z_, 0); + } + else + { + mpi_mod (a, a, p); /* a mod p */ + if (!mpi_cmp (a, p_3)) + { /* a==p-3 */ + mpi_powm (t4, t3, two, p); /* t4=t3^2 mod p */ + mpi_subm (t5, t1, t4, p); /* t5=t1-t4 mod p */ + mpi_addm (t4, t1, t4, p); /* t4=t1+t4 mod p */ + mpi_mulm (t5, t4, t5, p); /* t5=t4*t5 mod p */ + mpi_mulm (t4, three, t5, p); /* t4=3*t5 mod p */ + } + else + { + t4 = mpi_copy (a); /* t4=a */ + mpi_powm (t5, t3, two, p); /* t5=t3^2 mod p */ + mpi_powm (t5, t5, two, p); /* t5=t5^2 mod p */ + mpi_mulm (t5, t4, t5, p); /* t5=t4*t5 mod p */ + mpi_powm (t4, t1, two, p); /* t4=t1^2 mod p */ + mpi_mulm (t4, three, t4, p); /* t4=3*t4 mod p */ + mpi_addm (t4, t4, t5, p); /* t4=t4+t5 mod p */ + } + mpi_mulm (t3, t2, t3, p); /* t3=t2*t3 mod p */ + mpi_mulm (t3, two, t3, p); /* t3=2*t3 mod p */ + mpi_powm (aux, t2, two, p); /* t2=t2^2 mod p */ + t2 = mpi_copy (aux); + mpi_mulm (t5, t1, t2, p); /* t5=t1*t2 mod p */ + mpi_mulm (t5, four, t5, p); /* t5=4*t5 mod p */ + mpi_powm (t1, t4, two, p); /* t1=t4^2 mod p */ + mpi_mulm (aux, two, t5, p); + mpi_subm (t1, t1, aux, p); /* t1=t1-2*t5 mod p */ + mpi_powm (aux, t2, two, p); /* t2=t2^2 mod p */ + t2 = mpi_copy (aux); + mpi_mulm (t2, eight, t2, p); /* t2=8*t2 mod p */ + mpi_subm (t5, t5, t1, p); /* t5=t5-t1 mod p */ + mpi_mulm (t5, t4, t5, p); /* t5=t4*t5 mod p */ + mpi_subm (t2, t5, t2, p); /* t2=t5-t2 mod p */ + + mpi_set (R->x_, t1); + mpi_set (R->y_, t2); + mpi_set (R->z_, t3); + } + mpi_free (aux); + mpi_free (t7); + mpi_free (t6); + mpi_free (t5); + mpi_free (t4); + mpi_free (t3); + mpi_free (t2); + mpi_free (t1); + mpi_free (p); + mpi_free (p_3); + mpi_free (a); + mpi_free (eight); + mpi_free (four); + mpi_free (three); + mpi_free (two); + mpi_free (one); +} + + +/* + Point addition is the group operation. + + R = P0 + P1 + */ +static void +sum_points (point_t *R, point_t *P0, point_t *P1, elliptic_curve_t * base) +{ + gcry_mpi_t one, two; + gcry_mpi_t p; + gcry_mpi_t t1, t2, t3, t4, t5, t6, t7; + unsigned int nbits; + + one = mpi_alloc_set_ui (1); + two = mpi_alloc_set_ui (2); + p = mpi_copy (base->p_); + nbits = mpi_get_nbits (p); + t1 = mpi_new (nbits); + t2 = mpi_new (nbits); + t3 = mpi_new (nbits); + t4 = mpi_new (nbits); + t5 = mpi_new (nbits); + t6 = mpi_new (nbits); + t7 = mpi_new (nbits); + + if ( (!mpi_cmp (P1->x_, P0->x_)) + && (!mpi_cmp (P1->y_, P0->y_)) + && (!mpi_cmp (P1->z_, P0->z_)) ) /* P1 == P0 */ + { + duplicate_point (R, P0, base); + } + else if (point_at_infinity (*P0)) /* R == 0 && P1 == P1 */ + { + /* (!mpi_cmp_ui(P0->y_,0) || !mpi_cmp_ui(P0->z_,0))*/ + mpi_set (R->x_, P1->x_); + mpi_set (R->y_, P1->y_); + mpi_set (R->z_, P1->z_); + } + else if (point_at_infinity (*P1)) /* R == P0 && P0 == 0 */ + { + /* (!mpi_cmp_ui(P1->y_,0) || !mpi_cmp_ui(P1->z_,0)) */ + mpi_set (R->x_, P0->x_); + mpi_set (R->y_, P0->y_); + mpi_set (R->z_, P0->z_); + } + else + { + t1 = mpi_copy (P0->x_); /* t1=x0 */ + t2 = mpi_copy (P0->y_); /* t2=y0 */ + t3 = mpi_copy (P0->z_); /* t3=z0 */ + t4 = mpi_copy (P1->x_); /* t4=x1 */ + t5 = mpi_copy (P1->y_); /* t5=y2 */ + if (mpi_cmp (P1->z_, one)) /* z1 != 1 */ + { + /* fixme: Release old t6 or just set it. */ + t6 = mpi_copy (P1->z_); /* t6=z1 */ + mpi_powm (t7, t6, two, p); /* t7=t6^2 mod p */ + mpi_mulm (t1, t1, t7, p); /* t1=t1*t7 mod p */ + mpi_mulm (t7, t6, t7, p); /* t7=t6*t7 mod p */ + mpi_mulm (t2, t2, t7, p); /* t2=t2*t7 mod p */ + } + mpi_powm (t7, t3, two, p);/* t7=t3^2 mod p */ + mpi_mulm (t4, t4, t7, p); /* t4=t4*t7 mod p */ + mpi_mulm (t7, t3, t7, p); /* t7=t3*t7 mod p */ + mpi_mulm (t5, t5, t7, p); /* t5=t5*t7 mod p */ + mpi_subm (t4, t1, t4, p); /* t4=t1-t4 mod p */ + mpi_subm (t5, t2, t5, p); /* t5=t2-t5 mod p */ + + if (!mpi_cmp_ui (t4, 0)) /* t4==0 */ + { + if (!mpi_cmp_ui (t5, 0)) + { + /* return (0:0:0), it has a special mean. */ + if (DBG_CIPHER) + log_debug ("ecc sum_points: [0:0:0]!\n"); + mpi_set_ui (R->x_, 0); + mpi_set_ui (R->y_, 0); + mpi_set_ui (R->z_, 0); + } + else + { + if (DBG_CIPHER) + log_debug ("ecc sum_points: [1:1:0]!\n"); + mpi_set_ui (R->x_, 1); + mpi_set_ui (R->y_, 1); + mpi_set_ui (R->z_, 0); + } + } + else + { + mpi_mulm (t1, two, t1, p); + mpi_subm (t1, t1, t4, p); /* t1=2*t1-t4 mod p */ + mpi_mulm (t2, two, t2, p); + mpi_subm (t2, t2, t5, p); /* t2=2*t2-t5 mod p */ + if (mpi_cmp (P1->z_, one)) /* z1 != 1 */ + { + mpi_mulm (t3, t3, t6, p); /* t3=t3*t6 */ + } + mpi_mulm (t3, t3, t4, p); /* t3=t3*t4 mod p */ + mpi_powm (t7, t4, two, p); /* t7=t4^2 mod p */ + mpi_mulm (t4, t4, t7, p); /* t4=t4*t7 mod p */ + mpi_mulm (t7, t1, t7, p); /* t7=t1*t7 mod p */ + mpi_powm (t1, t5, two, p); /* t1=t5^2 mod p */ + mpi_subm (t1, t1, t7, p); /* t1=t1-t7 mod p */ + mpi_mulm (t6, two, t1, p); + mpi_subm (t7, t7, t6, p); /* t7=t7-2*t1 mod p */ + mpi_mulm (t5, t5, t7, p); /* t5=t5*t7 mod p */ + mpi_mulm (t4, t2, t4, p); /* t4=t2*t4 mod p */ + mpi_subm (t2, t5, t4, p); /* t2=t5-t4 mod p */ + mpi_invm (t6, two, p); + mpi_mulm (t2, t2, t6, p); /* t2 = t2/2 */ + + mpi_set (R->x_, t1); + mpi_set (R->y_, t2); + mpi_set (R->z_, t3); + } + } + + mpi_free (t7); + mpi_free (t6); + mpi_free (t5); + mpi_free (t4); + mpi_free (t3); + mpi_free (t2); + mpi_free (t1); + mpi_free (p); + mpi_free (two); + mpi_free (one); } /**************** - * The point inversion over F_p - * is a simple modular inversion - * of the Y coordinate. + * The modular power used without EC, + * is this function over EC. + return R = escalarP + + ESCALAR = input + P = input + BASE = input + R = output (caller must have intialized this point) + */ static void -invertPoint(point *P, ellipticCurve *base){ +escalar_mult (point_t *R, gcry_mpi_t escalar, point_t *P, + elliptic_curve_t *base) +{ + + gcry_mpi_t one, two, three; + gcry_mpi_t p; + gcry_mpi_t x1, y1, z1, z2, z3, k, h; + gcry_mpi_t xx, yy, zz; + unsigned int i, loops; + point_t P1, P2, P1_; + + if (DBG_CIPHER) + log_debug ("escalar_mult: begin\n"); + + one = mpi_alloc_set_ui (1); + two = mpi_alloc_set_ui (2); + three = mpi_alloc_set_ui (3); + + p = mpi_copy (base->p_); - mpi_subm(P->y_,base->p_,P->y_,base->p_);//y=p-y mod p + x1 = mpi_alloc_like (P->x_); + y1 = mpi_alloc_like (P->y_); + /* z1 is not yet intialized. */ + z2 = mpi_alloc_like (P->z_); + z3 = mpi_alloc_like (P->z_); + /* k is not yet intialized. */ + h = mpi_alloc_like (P->z_); + + + if (!mpi_cmp_ui (escalar, 0) || mpi_cmp_ui (P->z_, 0)) + { /* n=0 | Z=0 => [1:1:0] */ + mpi_set_ui (R->x_, 1); + mpi_set_ui (R->y_, 1); + mpi_set_ui (R->z_, 0); + } + xx = mpi_copy (P->x_); + zz = mpi_copy (P->z_); + z1 = mpi_copy (one); + + if (mpi_is_neg (escalar)) + { /* (-n)P=n(-P) */ + escalar->sign = 0; /* +n */ + k = mpi_copy (escalar); + yy = mpi_copy (P->y_); /* -P */ + mpi_invm (yy, yy, p); + } + else + { + k = mpi_copy (escalar); + yy = mpi_copy (P->y_); + } + if (!mpi_cmp (zz, one)) + { /* zz==1 */ + x1 = mpi_copy (xx); + y1 = mpi_copy (yy); + } + else + { + mpi_mulm (z2, zz, zz, p); /* z^2 */ + mpi_mulm (z3, zz, z2, p); /* z^3 */ + mpi_invm (z2, z2, p); /* 1/Z^2 */ + mpi_mulm (x1, xx, z2, p); /* xx/z^2 */ + mpi_invm (z3, z3, p); /* 1/z^3 */ + mpi_mulm (y1, yy, z3, p); /* yy/z^3 */ + } + mpi_mul (h, three, k); /* h=3k */ + loops = mpi_get_nbits (h); + i = loops - 2; /* i = l-1 = loops-2 */ + mpi_set (R->x_, xx); + mpi_set (R->y_, yy); + mpi_set (R->z_, zz); + P1.x_ = mpi_copy (x1); + P1.y_ = mpi_copy (y1); + P1.z_ = mpi_copy (z1); + while (i > 0) + { /* A.10.9. step 11 i from l-1 downto 1 */ + duplicate_point (R, R, base); + if (mpi_test_bit (h, i) == 1 && mpi_test_bit (k, i) == 0) + { /* h_i=1 & k_i=0 */ + P2 = point_copy (*R); + sum_points (R, &P2, &P1, base); /* R=P2+P1 over the base elliptic curve */ + } + if (mpi_test_bit (h, i) == 0 && mpi_test_bit (k, i) == 1) + { /* h_i=0 & k_i=1 */ + P2 = point_copy (*R); + P1_ = point_copy (P1); + invert_point (&P1_, base); + sum_points (R, &P2, &P1_, base); /* R=P2+P1_ over the base elliptic curve */ + } + i--; + } + + if (DBG_CIPHER) + log_debug ("escalar_mult: ready\n"); + + point_free (&P1); + point_free (&P2); + point_free (&P1_); + mpi_free (h); + mpi_free (k); + mpi_free (z3); + mpi_free (z2); + mpi_free (z1); + mpi_free (y1); + mpi_free (x1); + mpi_free (zz); + mpi_free (yy); + mpi_free (xx); + mpi_free (p); + mpi_free (three); + mpi_free (two); + mpi_free (one); } + /**************** - * Auxiliar function to made easy a struct copy. + * Solve the right side of the equation that defines a curve. + */ +static gcry_mpi_t +gen_y_2 (gcry_mpi_t x, elliptic_curve_t *base) +{ + gcry_mpi_t three; + gcry_mpi_t x_3, ax, axb, y; + gcry_mpi_t a, b, p; + unsigned int nbits; + + three = mpi_alloc_set_ui (3); + a = mpi_copy (base->a_); + b = mpi_copy (base->b_); + p = mpi_copy (base->p_); + nbits = mpi_get_nbits (p); + x_3 = mpi_new (nbits); + ax = mpi_new (nbits); + axb = mpi_new (nbits); + y = mpi_new (nbits); + + if (DBG_CIPHER) + log_debug ("ecc gen_y_2: Solving an elliptic equation.\n"); + + mpi_powm (x_3, x, three, p); /* x_3=x^3 mod p */ + mpi_mulm (ax, a, x, p); /* ax=a*x mod p */ + mpi_addm (axb, ax, b, p); /* axb=ax+b mod p */ + mpi_addm (y, x_3, axb, p); /* y=x^3+ax+b mod p */ + + if (DBG_CIPHER) + log_debug ("ecc gen_y_2: Solved.\n"); + + return y; /* The quadratic value of the coordinate if it exist. */ +} + + + + + + +/* + + E C C C O R E F U N C T I O N S + */ -static point -point_copy(point P){ - point R; - R.x_ = mpi_copy(P.x_); - R.y_ = mpi_copy(P.y_); - R.z_ = mpi_copy(P.z_); - return R; + +/* Generate a random secret scalar k with an order of p + + At the beginning this was identical to the code is in elgamal.c. + Later imporved by mmr. Further simplified by wk. */ +static gcry_mpi_t +gen_k (gcry_mpi_t p, int secure) +{ + gcry_mpi_t k; + unsigned int nbits; + + nbits = mpi_get_nbits (p); + k = (secure + ? mpi_alloc_secure ( mpi_get_nlimbs (p) ) + : mpi_alloc ( mpi_get_nlimbs (p) )); + + if (DBG_CIPHER) + log_debug ("choosing a random k of %u bits\n", nbits); + + gcry_mpi_randomize (k, nbits, GCRY_STRONG_RANDOM); + + mpi_mod (k, k, p); /* k = k mod p */ + + if (DBG_CIPHER) + progress ('\n'); + + return k; } + +/* Helper to scan a hex string. */ +static gcry_mpi_t +scanval (const char *string) +{ + gpg_error_t err; + gcry_mpi_t val; + + err = gcry_mpi_scan (&val, GCRYMPI_FMT_HEX, string, 0, NULL); + if (err) + log_fatal ("scanning ECC parameter failed: %s\n", gpg_strerror (err)); + return val; +} + + /**************** - * Made easy the free memory for a point struct. + * Generate the crypto system setup. + * As of now the fix NIST recommended values are used. + * The subgroup generator point is in another function: gen_big_point. */ -static void -point_free(point *P){ +static gpg_err_code_t +generate_curve (unsigned int nbits, elliptic_curve_t *curve) +{ + int idx; + + for (idx = 0; domain_parms[idx].desc; idx++) + if (nbits == domain_parms[idx].nbits) + break; + if (!domain_parms[idx].desc) + return GPG_ERR_INV_VALUE; + + curve->p_ = scanval (domain_parms[idx].p); + curve->a_ = scanval (domain_parms[idx].a); + curve->b_ = scanval (domain_parms[idx].b); + curve->n_ = scanval (domain_parms[idx].n); + curve->G.x_ = scanval (domain_parms[idx].g_x); + curve->G.y_ = scanval (domain_parms[idx].g_y); + curve->G.z_ = mpi_alloc_set_ui (1); + + /* Gx, Gy, Gz are planned to be generated by code like this: + if ( gen_big_point (&curve->n_, curve, &curve->G, nbits) == -1) + { + log_fatal ("ECC operation: Point generation failed\n"); + } + + A point of order 'n' is needed to generate a cyclic subgroup. + Over this cyclic subgroup it's defined the ECDLP. Now it use a + fix values from NIST FIPS PUB 186-2. Returns -1 if it isn't + possible. + static int + gen_big_point (gcry_mpi_t * prime, elliptic_curve_t * base, point_t * G, + unsigned int nbits) + { + unsigned int i=0; + gcry_mpi_t one; + point_t Big, P; + + one = mpi_alloc_set_ui(1); + G->x_ = mpi_alloc(mpi_get_nlimbs(*prime)); + G->y_ = mpi_alloc(mpi_get_nlimbs(*prime)); + G->z_ = mpi_alloc(mpi_get_nlimbs(*prime)); + + if( DBG_CIPHER )log_debug("Generating a Big point.\n"); + do{ + do{ + *P = genPoint(*prime,*base); + }while(PointAtInfinity(*P));//A random point in the curve that it's not PaI + escalarMult(base.h,&P,&G,&base);//cofactor (1 o 2), could be improved + }while(PointAtInfinity(G)); + if( DBG_CIPHER )log_debug("Big point generated.\n"); + if( DBG_CIPHER ){ + log_mpidump("Gx=",G->x_);log_mpidump("Gy=",G->y_);log_mpidump("Gz=",G->z_); + } + return 0; + } + */ + + if (DBG_CIPHER) + { + progress ('\n'); + log_mpidump ("ecc generation p= ", curve->p_); + log_mpidump ("ecc generation a= ", curve->a_); + log_mpidump ("ecc generation b= ", curve->b_); + log_mpidump ("ecc generation n= ", curve->n_); + log_mpidump ("ecc generation Gx= ", curve->G.x_); + log_mpidump ("ecc generation Gy= ", curve->G.y_); + log_mpidump ("ecc generation Gz= ", curve->G.z_); + } + if (DBG_CIPHER) + progress ('\n'); - mpi_free(P->x_); - mpi_free(P->y_); - mpi_free(P->z_); + return 0; } + /**************** - * Turn a projective coordinate to affine, return 0 (or 1 in error case). - * Needed to verify a signature. - * - * y_coordinate it is never used, we could do without it. //!! + * First obtain the setup. Over the finite field randomize an scalar + * secret value, and calculate the public point. + */ +static gpg_err_code_t +generate_key (ECC_secret_key *sk, unsigned int nbits) +{ + gpg_err_code_t err; + elliptic_curve_t E; + gcry_mpi_t d; + point_t Q, G; + + err = generate_curve (nbits, &E); + if (err) + return err; + + d = mpi_snew (nbits); + if (DBG_CIPHER) + log_debug ("choosing a random x of size %u\n", nbits); + d = gen_k (E.n_, 2); /* generate_secret_prime(nbits); */ + G = point_copy (E.G); + + /* Compute Q. */ + point_init (&Q); + escalar_mult (&Q, d, &E.G, &E); + + /* Copy the stuff to the key structures. */ + sk->E.p_ = mpi_copy (E.p_); + sk->E.a_ = mpi_copy (E.a_); + sk->E.b_ = mpi_copy (E.b_); + sk->E.G = point_copy (E.G); + sk->E.n_ = mpi_copy (E.n_); + sk->Q = point_copy (Q); + sk->d = mpi_copy (d); + + /* Now we can test our keys (this should never fail!). */ + test_keys (sk, nbits - 64); + + point_free (&Q); + mpi_free (d); + curve_free (&E); + + return 0; +} + + +/**************** + * To verify correct skey it use a random information. + * First, encrypt and decrypt this dummy value, + * test if the information is recuperated. + * Second, test with the sign and verify functions. */ -static int -point_affine(point *P, MPI x, MPI y, ellipticCurve *base){ +static void +test_keys (ECC_secret_key *sk, unsigned int nbits) +{ + ECC_public_key pk; + gcry_mpi_t test = mpi_new (nbits); + point_t R_; + gcry_mpi_t c = mpi_new (nbits); + gcry_mpi_t out = mpi_new (nbits); + gcry_mpi_t r = mpi_new (nbits); + gcry_mpi_t s = mpi_new (nbits); - //MPI z; - MPI z1,z2,z3; + if (DBG_CIPHER) + log_debug ("Testing key.\n"); - z1 = mpi_alloc(0); - z2 = mpi_alloc(0); - z3 = mpi_alloc(0); + point_init (&R_); - if (PointAtInfinity(*P)){ - if( DBG_CIPHER )log_info("Affine: Point at Infinity does NOT exist in the affine plane!\n"); - return 1; - } + pk.E = curve_copy (sk->E); + pk.Q = point_copy (sk->Q); + + gcry_mpi_randomize (test, nbits, GCRY_WEAK_RANDOM); - mpi_invm(z1,P->z_,base->p_); // z1 =Z^{-1} (mod p) - mpi_mulm(z2,z1,z1,base->p_); // z2 =Z^(-2) (mod p) - mpi_mulm(z3,z2,z1,base->p_); // z3 =Z^(-3) (mod p) - mpi_mulm(x,P->x_,z2,base->p_); - mpi_mulm(y,P->y_,z3,base->p_); +#if 0 + doEncrypt (test, &pk, &R_, c); + + out = decrypt (out, sk, R_, c); + + if (mpi_cmp (test, out)) /* test!=out */ + log_fatal ("ECELG operation: encrypt, decrypt failed\n"); + if (DBG_CIPHER) + log_debug ("ECELG operation: encrypt, decrypt ok.\n"); +#endif + + sign (test, sk, &r, &s); + + if (!verify (test, &pk, r, s)) + { + log_fatal ("ECDSA operation: sign, verify failed\n"); + } - mpi_free(z1); - mpi_free(z2); - mpi_free(z3); - return 0; + if (DBG_CIPHER) + log_debug ("ECDSA operation: sign, verify ok.\n"); + + point_free (&pk.Q); + curve_free (&pk.E); + + point_free (&R_); + mpi_free (s); + mpi_free (r); + mpi_free (out); + mpi_free (c); + mpi_free (test); } /**************** - * Auxiliar function to made easy a struct copy. + * To check the validity of the value, recalculate the correspondence + * between the public value and de secret one. */ -static ellipticCurve -curve_copy(ellipticCurve E){ +static int +check_secret_key (ECC_secret_key * sk) +{ + point_t Q; + gcry_mpi_t y_2, y2 = mpi_alloc (0); + + /* ?primarity test of 'p' */ + /* (...) //!! */ + /* G in E(F_p) */ + y_2 = gen_y_2 (sk->E.G.x_, &sk->E); /* y^2=x^3+a*x+b */ + mpi_mulm (y2, sk->E.G.y_, sk->E.G.y_, sk->E.p_); /* y^2=y*y */ + if (mpi_cmp (y_2, y2)) + { + if (DBG_CIPHER) + log_debug ("Bad check: Point 'G' does not belong to curve 'E'!\n"); + return (1); + } + /* G != PaI */ + if (point_at_infinity (sk->E.G)) + { + if (DBG_CIPHER) + log_debug ("Bad check: 'G' cannot be Point at Infinity!\n"); + return (1); + } + /* ?primarity test of 'n' */ + /* (...) //!! */ + /* ?(p-sqrt(p)) < n < (p+sqrt(p)) */ + /* ?n!=p */ + /* ?(n^k) mod p !=1 for k=1 to 31 (from GOST) or k=1 to 50 (from MIRACL) */ + /* Q=[n]G over E = PaI */ + + point_init (&Q); + escalar_mult (&Q, sk->E.n_, &sk->E.G, &sk->E); + if (!point_at_infinity (Q)) + { + if (DBG_CIPHER) + log_debug ("check_secret_key: E is not a curve of order n\n"); + point_free (&Q); + return 1; + } + /* pubkey cannot be PaI */ + if (point_at_infinity (sk->Q)) + { + if (DBG_CIPHER) + log_debug ("Bad check: Q can not be a Point at Infinity!\n"); + return (1); + } + /* pubkey = [d]G over E */ + escalar_mult (&Q, sk->d, &sk->E.G, &sk->E); + if ((Q.x_ == sk->Q.x_) && (Q.y_ == sk->Q.y_) && (Q.z_ == sk->Q.z_)) + { + if (DBG_CIPHER) + log_debug + ("Bad check: There is NO correspondence between 'd' and 'Q'!\n"); + return (1); + } + point_free (&Q); + return 0; +} + + +#if 0 +/**************** + * Encrypt a number and obtain and struct (R,c) + */ +static void +doEncrypt (gcry_mpi_t input, ECC_public_key * pkey, point_t * R, gcry_mpi_t c) +{ - ellipticCurve R; + gcry_mpi_t k, p, x, y; + point_t P, Q, G; + elliptic_curve_t E; + + k = mpi_alloc (0); + p = mpi_copy (pkey->E.p_); + x = mpi_alloc (0); + y = mpi_alloc (0); + Q = point_copy (pkey->Q); + G = point_copy (pkey->E.G); + E = curve_copy (pkey->E); + + k = gen_k (p, 1); /* 2nd parametre: how much security? */ + escalarMult (k, &Q, &P, &E); /* P=[k]Q=[k]([d]G) */ + escalarMult (k, &G, R, &E); /* R=[k]G */ + /* IFP weakness//mpi_mul(c,input,Q.x_);//c=input*Q_x */ + /* MMR Use affine conversion befor extract x-coordinate */ + if (point_affine (&P, x, y, &E)) + { /* Q cannot turn to affine coordinate */ + if (DBG_CIPHER) + { + log_debug ("Encrypting: Cannot turn to affine.\n"); + } + } + /* MMR According to the standard P1363 we can not use x-coordinate directly. */ + /* It is necessary to add hash-operation later. */ + /* As the maximal length of a key for the symmetric cipher is 256 bit it is possible to take hash-function SHA256. */ + sha256_hashing (x, &x); + aes256_encrypting (x, input, &c); + + if (DBG_CIPHER) + { + log_debug ("doEncrypt: end.\n"); + } +} +#endif /*0*/ + +#if 0 +/**************** + * Undo the ciphertext + */ +static gcry_mpi_t +decrypt (gcry_mpi_t output, ECC_secret_key * skey, point_t R, gcry_mpi_t c) +{ - R.p_ = mpi_copy(E.p_); - R.a_ = mpi_copy(E.a_); - R.b_ = mpi_copy(E.b_); - R.G = point_copy(E.G); - R.n_ = mpi_copy(E.n_); + gcry_mpi_t p, inv, x, y; + point_t P, Q; + elliptic_curve_t E; + + p = mpi_copy (skey->E.p_); + inv = mpi_alloc (0); + x = mpi_alloc (0); + y = mpi_alloc (0); + Q = point_copy (skey->Q); + E = curve_copy (skey->E); + + escalarMult (skey->d, &R, &P, &E); /* P=[d]R */ + /* That is like: mpi_fdiv_q(output,c,Q.x_); */ + /* IFP weakness//mpi_invm(inv,Q.x_,p);//inv=Q{_x}^-1 (mod p) */ + /* IFP weakness//mpi_mulm(output,c,inv,p);//output=c*inv (mod p) */ + /* MMR Use affine conversion befor extract x-coordinate */ + if (point_affine (&P, x, y, &E)) + { /* Q cannot turn to affine coordinate */ + if (DBG_CIPHER) + { + log_debug ("Encrypting: Cannot turn to affine.\n"); + } + } + sha256_hashing (x, &x); + aes256_decrypting (x, c, &output); - return R; + if (DBG_CIPHER) + { + log_debug ("decrypt: end.\n"); + } + return (output); } +#endif /*0*/ /**************** - * Made easy the free memory for a setup struct. + * Return the signature struct (r,s) from the message hash. */ static void -curve_free(ellipticCurve *E){ - mpi_free(E->p_); - mpi_free(E->a_); - mpi_free(E->b_); - point_free(&E->G); - mpi_free(E->n_); +sign (gcry_mpi_t input, ECC_secret_key *skey, gcry_mpi_t *r, gcry_mpi_t *s) +{ + gcry_mpi_t k, i, dr, sum, k_1, x, y; + point_t G, I; + elliptic_curve_t E; + + k = mpi_alloc (0); + i = mpi_alloc (0); + dr = mpi_alloc (0); + sum = mpi_alloc (0); + k_1 = mpi_alloc (0); + x = mpi_alloc (0); + y = mpi_alloc (0); + G = point_copy (skey->E.G); + E = curve_copy (skey->E); + *r = mpi_alloc (0); + *s = mpi_alloc (0); + + point_init (&I); + + while (!mpi_cmp_ui (*s, 0)) /* s == 0 */ + { + while (!mpi_cmp_ui (*r, 0)) /* r == 0 */ + { + k = gen_k (E.p_, 1); + escalar_mult (&I, k, &G, &E); /* I = [k]G */ + if (point_affine (&I, x, y, &E)) + { + if (DBG_CIPHER) + log_debug ("ecc sign: Cannot turn to affine. " + " Cannot complete sign.\n"); + /* FIXME: Shouldn't we return an error now? */ + } + i = mpi_copy (x); /* i = I_x */ + mpi_mod (*r, i, E.n_); /* r = i mod n */ + /* Fixme: release k, i and I? */ + } + mpi_mulm (dr, skey->d, *r, E.n_); /* dr = d*r mod n */ + mpi_addm (sum, input, dr, E.n_); /* sum = hash + (d*r) mod n */ + mpi_invm (k_1, k, E.n_); /* k_1 = k^(-1) mod n */ + mpi_mulm (*s, k_1, sum, E.n_); /* s = k^(-1)*(hash+(d*r)) mod n */ + } + if (DBG_CIPHER) + log_debug ("ess sign: end\n"); + + /* Fixme: What about releasing G and E? */ + mpi_free (y); + mpi_free (x); + mpi_free (k_1); + mpi_free (sum); + mpi_free (dr); + mpi_free (i); + mpi_free (k); } /**************** - * Boolean generator to choose between to coordinates. + * Check if the struct (r,s) is for the hash value that it have. + * Returns: 0 = does not verify + * 1 = verifies. */ -static MPI -gen_bit(){ +static int +verify (gcry_mpi_t input, ECC_public_key *pkey, gcry_mpi_t r, gcry_mpi_t s) +{ + gcry_mpi_t r_, s_, h, h1, h2, i, x, y; + point_t Q, Q1, Q2, G; + elliptic_curve_t E; + + /* Fixme: we need to release quite some values. */ + + r_ = mpi_alloc (0); + s_ = mpi_alloc (0); + h = mpi_alloc (0); + h1 = mpi_alloc (0); + h2 = mpi_alloc (0); + x = mpi_alloc (0); + y = mpi_alloc (0); + G = point_copy (pkey->E.G); + E = curve_copy (pkey->E); + + mpi_mod (r_, r, pkey->E.n_); /* r = r mod E_n */ + mpi_mod (s_, s, pkey->E.n_); /* s = s mod E_n */ + + /* Check that the input parameters are valid. */ + if (mpi_cmp (r_, r) || mpi_cmp (s_, s)) /* r_ != r || s_ != s */ + { + if (DBG_CIPHER) + log_debug ("ecc verification: No valid values.\n"); + return 0; + } + + point_init (&Q); + point_init (&Q1); + point_init (&Q2); + + mpi_invm (h, s, E.n_); /* h = s^(-1) (mod n) */ + mpi_mulm (h1, input, h, E.n_); /* h1 = hash * s^(-1) (mod n) */ + escalar_mult (&Q1, h1, &G, &E); /* Q1 = [ hash * s^(-1) ]G */ + mpi_mulm (h2, r, h, E.n_); /* h2 = r * s^(-1) (mod n) */ + escalar_mult (&Q2, h2, &pkey->Q, &E); /* Q2 = [ r * s^(-1) ]Q */ + sum_points (&Q, &Q1, &Q2, &E);/* Q = ([hash * s^(-1)]G) + ([r * s^(-1)]Q) */ + + if (point_at_infinity (Q)) + { + if (DBG_CIPHER) + log_debug ("ecc verification: Rejected.\n"); + return 0; /* Rejected. */ + } + if (point_affine (&Q, x, y, &E)) + { + if (DBG_CIPHER) + log_debug ("ecc verification: Cannot turn to affine. Rejected.\n"); + return 0; /* Rejected. */ + } + + i = mpi_copy (x); /* Give the x_coordinate */ + mpi_mod (i, i, E.n_); /* i = i mod E_n */ - MPI aux = mpi_alloc_set_ui(0); + if (!mpi_cmp (i, r)) /* i==r => Return 0 (distance between them). */ + { + if (DBG_CIPHER) + log_debug ("ecc verification: Accepted.\n"); + return 1; /* Accepted. */ + } + if (DBG_CIPHER) + log_debug ("ecc verification: Not verified.\n"); - //Get one random bit, with less security level, and translate it to an MPI. - mpi_set_buffer( aux, get_random_bits( 1, 0, 1 ), 1, 0 );//gen_k(...) + /* Fixme: release Q, Q1 and Q2. */ - return aux;//b; + return 0; } + /**************** - * Solve the right side of the equation that define a curve. + * Generate a random point over an Elliptic curve is the first step to + * find a random cyclic subgroup generator. + * + * !! At this moment it isn't used !! //!! */ -static MPI -gen_y_2(MPI x, ellipticCurve *base){ +#if 0 +static point_t +gen_point (gcry_mpi_t prime, elliptic_curve_t base) +{ - MPI three; - MPI x_3,ax,axb,y; - MPI a,b,p; + unsigned int i = 0; + gcry_mpi_t x, y_2, y; + gcry_mpi_t one, one_neg, bit; + point_t P; + + x = mpi_alloc (mpi_get_nlimbs (base.p_)); + y_2 = mpi_alloc (mpi_get_nlimbs (base.p_)); + y = mpi_alloc (mpi_get_nlimbs (base.p_)); + one = mpi_alloc_set_ui (1); + one_neg = mpi_alloc (mpi_get_nlimbs (one)); + mpi_invm (one_neg, one, base.p_); + + if (DBG_CIPHER) + log_debug ("Generating a normal point.\n"); + do + { + x = gen_k (base.p_, 1); /* generate_public_prime(mpi_get_nlimbs(base.n_)*BITS_PER_MPI_LIMB); */ + do + { + y_2 = gen_y_2 (x, &base); /* x^3+ax+b (mod p) */ + mpi_add_ui (x, x, 1); + i++; + } + while (!mpi_cmp_ui (y_2, 0) && i < 0xf); /* Try to find a valid value until 16 iterations. */ + i = 0; + y = existSquareRoot (y_2, base.p_); + } + while (!mpi_cmp_ui (y, 0)); /* Repeat until a valid coordinate is found. */ + bit = gen_bit (); /* generate one bit */ + if (mpi_cmp_ui (bit, 1)) + { /* choose the y coordinate */ + mpi_invm (y, y, base.p_); /* mpi_powm(y, y, one_neg,base.p_); */ + } + if (DBG_CIPHER) + log_debug ("Normal point generated.\n"); + + P.x_ = mpi_copy (x); + P.y_ = mpi_copy (y); + P.z_ = mpi_copy (one); + + mpi_free (bit); + mpi_free (one_neg); + mpi_free (one); + mpi_free (y); + mpi_free (y_2); + mpi_free (x); - three = mpi_alloc_set_ui(3); - a = mpi_copy(base->a_); - b = mpi_copy(base->b_), - p = mpi_copy(base->p_); - x_3 = mpi_alloc(mpi_get_nlimbs(p)); - ax = mpi_alloc(mpi_get_nlimbs(p)); - axb = mpi_alloc(mpi_get_nlimbs(p)); - y = mpi_alloc(mpi_get_nlimbs(p)); + return (P); +} +#endif /*0*/ - if( DBG_MPI )log_info("solving an elliptic equation.\n"); +/**************** + * Boolean generator to choose between to coordinates. + */ +#if 0 +static gcry_mpi_t +gen_bit () +{ + gcry_mpi_t aux = mpi_alloc_set_ui (0); - mpi_powm(x_3,x,three,p);//x_3=x^3 mod p - mpi_mulm(ax,a,x,p);//ax=a*x mod p - mpi_addm(axb,ax,b,p);//axb=ax+b mod p - mpi_addm(y,x_3,axb,p);//y=x^3+ax+b mod p + /* FIXME: This is highly ineffective but the whole function is used + only at one place. */ - if( DBG_MPI )log_info("solved.\n"); + /* Get one random bit, with less security level, and translate it to + an MPI. */ + mpi_set_buffer (aux, get_random_bits (1, 0, 1), 1, 0); /* gen_k(...) */ - return y;//the quadratic value of the coordinate if it exist. + return aux; /* b; */ } +#endif /*0*/ -//Function to solve an IFP ECElGamal weakness: -// sha256_hashing() -// aes256_encrypting() -// aes356_decrypting() + + +#if 0 +/* Function to solve an IFP ECElGamal weakness: */ +/* sha256_hashing() */ +/* aes256_encrypting() */ +/* aes356_decrypting() */ /**************** * Compute 256 bit hash value from input MPI. * Use SHA256 Algorithm. */ -static void -sha256_hashing(MPI input, MPI *output){ // +static void +sha256_hashing (gcry_mpi_t input, gcry_mpi_t * output) +{ /* */ - int sign; - byte *hash_inp_buf; - byte hash_out_buf[32]; - MD_HANDLE hash = md_open(8,1);//algo SHA256 in secure mode + int sign; + byte *hash_inp_buf; + byte hash_out_buf[32]; + MD_HANDLE hash = md_open (8, 1); /* algo SHA256 in secure mode */ - unsigned int nbytes; + unsigned int nbytes; - hash_inp_buf = mpi_get_secure_buffer( input, &nbytes, &sign );//convert MPI input to string + hash_inp_buf = mpi_get_secure_buffer (input, &nbytes, &sign); /* convert gcry_mpi_t input to string */ - md_write( hash, hash_inp_buf, nbytes );//hashing input string - wipememory( hash_inp_buf, sizeof hash_inp_buf ); // burn temp value - xfree(hash_inp_buf); + md_write (hash, hash_inp_buf, nbytes); /* hashing input string */ + wipememory (hash_inp_buf, sizeof hash_inp_buf); /* burn temp value */ + xfree (hash_inp_buf); - md_digest(hash, 8, hash_out_buf, 32); - mpi_set_buffer( *output, hash_out_buf, 32, 0 );// convert 256 bit digest to MPI + md_digest (hash, 8, hash_out_buf, 32); + mpi_set_buffer (*output, hash_out_buf, 32, 0); /* convert 256 bit digest to MPI */ - wipememory( hash_out_buf, sizeof hash_out_buf ); // burn temp value - md_close(hash);// destroy and free hash state. + wipememory (hash_out_buf, sizeof hash_out_buf); /* burn temp value */ + md_close (hash); /* destroy and free hash state. */ } @@ -1415,33 +1628,34 @@ sha256_hashing(MPI input, MPI *output){ // * Use AES256 algorithm. */ -static void -aes256_encrypting(MPI key, MPI input, MPI *output){ // +static void +aes256_encrypting (gcry_mpi_t key, gcry_mpi_t input, gcry_mpi_t * output) +{ /* */ - int sign; - byte *key_buf; - byte *cipher_buf; + int sign; + byte *key_buf; + byte *cipher_buf; - unsigned int keylength; - unsigned int nbytes; + unsigned int keylength; + unsigned int nbytes; - CIPHER_HANDLE cipher = cipher_open(9,CIPHER_MODE_CFB,1);//algo AES256 CFB mode in secure memory - cipher_setiv( cipher, NULL, 0 ); // Zero IV + CIPHER_HANDLE cipher = cipher_open (9, CIPHER_MODE_CFB, 1); /* algo AES256 CFB mode in secure memory */ + cipher_setiv (cipher, NULL, 0); /* Zero IV */ - key_buf = mpi_get_secure_buffer( key, &keylength, &sign );//convert MPI key to string - cipher_setkey( cipher, key_buf, keylength ); - wipememory( key_buf, sizeof key_buf ); // burn temp value - xfree(key_buf); + key_buf = mpi_get_secure_buffer (key, &keylength, &sign); /* convert MPI key to string */ + cipher_setkey (cipher, key_buf, keylength); + wipememory (key_buf, sizeof key_buf); /* burn temp value */ + xfree (key_buf); - cipher_buf = mpi_get_secure_buffer( input, &nbytes, &sign );//convert MPI input to string + cipher_buf = mpi_get_secure_buffer (input, &nbytes, &sign); /* convert MPI input to string */ - cipher_encrypt( cipher, cipher_buf+1, cipher_buf+1, nbytes-1);// - cipher_close(cipher);// destroy and free cipher state. + cipher_encrypt (cipher, cipher_buf + 1, cipher_buf + 1, nbytes - 1); /* */ + cipher_close (cipher); /* destroy and free cipher state. */ - mpi_set_buffer( *output, cipher_buf, nbytes, 0 );// convert encrypted string to MPI - wipememory( cipher_buf, sizeof cipher_buf ); // burn temp value - xfree(cipher_buf); + mpi_set_buffer (*output, cipher_buf, nbytes, 0); /* convert encrypted string to MPI */ + wipememory (cipher_buf, sizeof cipher_buf); /* burn temp value */ + xfree (cipher_buf); } /**************** @@ -1449,285 +1663,332 @@ aes256_encrypting(MPI key, MPI input, MPI *output){ // * Use AES256 algorithm. */ -static void -aes256_decrypting(MPI key, MPI input, MPI *output){ // +static void +aes256_decrypting (gcry_mpi_t key, gcry_mpi_t input, gcry_mpi_t * output) +{ /* */ - int sign; - byte *key_buf; - byte *cipher_buf; + int sign; + byte *key_buf; + byte *cipher_buf; - unsigned int keylength; - unsigned int nbytes; + unsigned int keylength; + unsigned int nbytes; - CIPHER_HANDLE cipher = cipher_open(9,CIPHER_MODE_CFB,1);//algo AES256 CFB mode in secure memory - cipher_setiv( cipher, NULL, 0 ); // Zero IV + CIPHER_HANDLE cipher = cipher_open (9, CIPHER_MODE_CFB, 1); /* algo AES256 CFB mode in secure memory */ + cipher_setiv (cipher, NULL, 0); /* Zero IV */ - key_buf = mpi_get_secure_buffer( key, &keylength, &sign );//convert MPI input to string - cipher_setkey( cipher, key_buf, keylength ); - wipememory( key_buf, sizeof key_buf ); // burn temp value - xfree(key_buf); + key_buf = mpi_get_secure_buffer (key, &keylength, &sign); /* convert MPI input to string */ + cipher_setkey (cipher, key_buf, keylength); + wipememory (key_buf, sizeof key_buf); /* burn temp value */ + xfree (key_buf); - cipher_buf = mpi_get_secure_buffer( input, &nbytes, &sign );//convert MPI input to string; + cipher_buf = mpi_get_secure_buffer (input, &nbytes, &sign); /* convert MPI input to string; */ - cipher_decrypt( cipher, cipher_buf+1, cipher_buf+1, nbytes-1 );// - cipher_close(cipher);// destroy and free cipher state. + cipher_decrypt (cipher, cipher_buf + 1, cipher_buf + 1, nbytes - 1); /* */ + cipher_close (cipher); /* destroy and free cipher state. */ - mpi_set_buffer( *output, cipher_buf, nbytes, 0 );// convert encrypted string to MPI - wipememory( cipher_buf, sizeof cipher_buf ); // burn temp value - xfree(cipher_buf); + mpi_set_buffer (*output, cipher_buf, nbytes, 0); /* convert encrypted string to MPI */ + wipememory (cipher_buf, sizeof cipher_buf); /* burn temp value */ + xfree (cipher_buf); } -//End of IFP ECElGamal weakness functions. + +/* End of IFP ECElGamal weakness functions. */ +#endif /*0*/ /********************************************* ************** interface ****************** *********************************************/ -int -ecc_generate( int algo, unsigned nbits, MPI *skey, MPI **retfactors ) + +static gcry_err_code_t +ecc_generate (int algo, unsigned int nbits, unsigned long dummy, + gcry_mpi_t *skey, gcry_mpi_t **retfactors) { + gpg_err_code_t err; + ECC_secret_key sk; + + (void)algo; + + /* Make an empty list of factors. */ + *retfactors = gcry_calloc ( 1, sizeof **retfactors ); + if (!*retfactors) + return gpg_err_code_from_syserror (); + + err = generate_key (&sk, nbits); + if (err) + { + gcry_free (*retfactors); + *retfactors = NULL; + return err; + } + + skey[0] = sk.E.p_; + skey[1] = sk.E.a_; + skey[2] = sk.E.b_; + skey[3] = sk.E.G.x_; + skey[4] = sk.E.G.y_; + skey[5] = sk.E.G.z_; + skey[6] = sk.E.n_; + skey[7] = sk.Q.x_; + skey[8] = sk.Q.y_; + skey[9] = sk.Q.z_; + skey[10] = sk.d; + + if (DBG_CIPHER) + { + progress ('\n'); + + log_mpidump ("[ecc] p= ", skey[0]); + log_mpidump ("[ecc] a= ", skey[1]); + log_mpidump ("[ecc] b= ", skey[2]); + log_mpidump ("[ecc] Gx= ", skey[3]); + log_mpidump ("[ecc] Gy= ", skey[4]); + log_mpidump ("[ecc] Gz= ", skey[5]); + log_mpidump ("[ecc] n= ", skey[6]); + log_mpidump ("[ecc] Qx= ", skey[7]); + log_mpidump ("[ecc] Qy= ", skey[8]); + log_mpidump ("[ecc] Qz= ", skey[9]); + log_mpidump ("[ecc] d= ", skey[10]); + } - ECC_secret_key sk; - - if( !is_ECC(algo) ) - return G10ERR_PUBKEY_ALGO; - - generateKey( &sk, nbits, retfactors ); - - skey[0] = sk.E.p_; - skey[1] = sk.E.a_; - skey[2] = sk.E.b_; - skey[3] = sk.E.G.x_; - skey[4] = sk.E.G.y_; - skey[5] = sk.E.G.z_; - skey[6] = sk.E.n_; - skey[7] = sk.Q.x_; - skey[8] = sk.Q.y_; - skey[9] = sk.Q.z_; - skey[10] = sk.d; - - if( DBG_CIPHER ) { - progress('\n'); - - log_mpidump("[ecc] p= ", skey[0]); - log_mpidump("[ecc] a= ", skey[1]); - log_mpidump("[ecc] b= ", skey[2]); - log_mpidump("[ecc] Gx= ", skey[3]); - log_mpidump("[ecc] Gy= ", skey[4]); - log_mpidump("[ecc] Gz= ", skey[5]); - log_mpidump("[ecc] n= ", skey[6]); - log_mpidump("[ecc] Qx= ", skey[7]); - log_mpidump("[ecc] Qy= ", skey[8]); - log_mpidump("[ecc] Qz= ", skey[9]); - log_mpidump("[ecc] d= ", skey[10]); - } - - if( DBG_CIPHER ){log_info("ECC key Generated.\n");} - return 0; + if (DBG_CIPHER) + { + log_debug ("ECC key Generated.\n"); + } + return 0; } -int -ecc_check_secret_key( int algo, MPI *skey ) +static gcry_err_code_t +ecc_check_secret_key (int algo, gcry_mpi_t *skey) { - ECC_secret_key sk; - - if( !is_ECC(algo) ) - return G10ERR_PUBKEY_ALGO; - if(!skey[0] || !skey[1] || !skey[2] || !skey[3] || !skey[4] || !skey[5] || !skey[6] || !skey[7] || !skey[8] || !skey[9] || !skey[10]) - return G10ERR_BAD_MPI; - - if( DBG_CIPHER ){log_info("ECC check secret key.\n");} - sk.E.p_ = skey[0]; - sk.E.a_ = skey[1]; - sk.E.b_ = skey[2]; - sk.E.G.x_ = skey[3]; - sk.E.G.y_ = skey[4]; - sk.E.G.z_ = skey[5]; - sk.E.n_ = skey[6]; - sk.Q.x_ = skey[7]; - sk.Q.y_ = skey[8]; - sk.Q.z_ = skey[9]; - sk.d = skey[10]; - - if( check_secret_key(&sk)){ - if( DBG_CIPHER )log_info("Bad check: Bad secret key.\n"); - return G10ERR_BAD_SECKEY; - } - return 0; -} + ECC_secret_key sk; + (void)algo; + if (!skey[0] || !skey[1] || !skey[2] || !skey[3] || !skey[4] || !skey[5] + || !skey[6] || !skey[7] || !skey[8] || !skey[9] || !skey[10]) + return GPG_ERR_BAD_MPI; -int -ecc_encrypt( int algo, MPI *resarr, MPI data, MPI *pkey ) -{ - ECC_public_key pk; - point R; - - if( algo != PUBKEY_ALGO_ECC && algo != PUBKEY_ALGO_ECC_E ) - return G10ERR_PUBKEY_ALGO; - if( !data || !pkey[0] || !pkey[1] || !pkey[2] || !pkey[3] || !pkey[4] || !pkey[5] || !pkey[6] || !pkey[7] || !pkey[8] || !pkey[9]) - return G10ERR_BAD_MPI; - - if( DBG_CIPHER ){log_info("ECC encrypt.\n");} - pk.E.p_ = pkey[0]; - pk.E.a_ = pkey[1]; - pk.E.b_ = pkey[2]; - pk.E.G.x_ = pkey[3]; - pk.E.G.y_ = pkey[4]; - pk.E.G.z_ = pkey[5]; - pk.E.n_ = pkey[6]; - pk.Q.x_ = pkey[7]; - pk.Q.y_ = pkey[8]; - pk.Q.z_ = pkey[9]; - - R.x_ = resarr[0] = mpi_alloc( mpi_get_nlimbs( pk.Q.x_ ) ); - R.y_ = resarr[1] = mpi_alloc( mpi_get_nlimbs( pk.Q.y_ ) ); - R.z_ = resarr[2] = mpi_alloc( mpi_get_nlimbs( pk.Q.z_ ) ); - resarr[3] = mpi_alloc( mpi_get_nlimbs( pk.E.p_ ) ); - - doEncrypt(data, &pk, &R, resarr[3]); - - resarr[0] = mpi_copy(R.x_); - resarr[1] = mpi_copy(R.y_); - resarr[2] = mpi_copy(R.z_); - return 0; + if (DBG_CIPHER) + { + log_debug ("ECC check secret key.\n"); + } + sk.E.p_ = skey[0]; + sk.E.a_ = skey[1]; + sk.E.b_ = skey[2]; + sk.E.G.x_ = skey[3]; + sk.E.G.y_ = skey[4]; + sk.E.G.z_ = skey[5]; + sk.E.n_ = skey[6]; + sk.Q.x_ = skey[7]; + sk.Q.y_ = skey[8]; + sk.Q.z_ = skey[9]; + sk.d = skey[10]; + + if (check_secret_key (&sk)) + { + if (DBG_CIPHER) + log_debug ("Bad check: Bad secret key.\n"); + return GPG_ERR_BAD_SECKEY; + } + return 0; } -int -ecc_decrypt( int algo, MPI *result, MPI *data, MPI *skey ) + +#if 0 +static int +ecc_encrypt_FIXME (int algo, gcry_mpi_t * resarr, gcry_mpi_t data, gcry_mpi_t * pkey) { - ECC_secret_key sk; - point R; - - if( algo != PUBKEY_ALGO_ECC && algo != PUBKEY_ALGO_ECC_E ) - return G10ERR_PUBKEY_ALGO; - if( !data[0] || !data[1] || !data[2] || !data[3] || !skey[0] || !skey[1] || !skey[2] || !skey[3] || !skey[4] || !skey[5] || !skey[6] || !skey[7] || !skey[8] || !skey[9] || !skey[10]) - return G10ERR_BAD_MPI; - - if( DBG_CIPHER ){log_info("ECC decrypt.\n");} - R.x_ = data[0]; - R.y_ = data[1]; - R.z_ = data[2]; - sk.E.p_ = skey[0]; - sk.E.a_ = skey[1]; - sk.E.b_ = skey[2]; - sk.E.G.x_ = skey[3]; - sk.E.G.y_ = skey[4]; - sk.E.G.z_ = skey[5]; - sk.E.n_ = skey[6]; - sk.Q.x_ = skey[7]; - sk.Q.y_ = skey[8]; - sk.Q.z_ = skey[9]; - sk.d = skey[10]; - - *result = mpi_alloc_secure( mpi_get_nlimbs( sk.E.p_ ) ); - *result = decrypt( *result, &sk, R, data[3]); - return 0; + ECC_public_key pk; + point R; + + if (algo != PUBKEY_ALGO_ECC && algo != PUBKEY_ALGO_ECC_E) + return G10ERR_PUBKEY_ALGO; + if (!data || !pkey[0] || !pkey[1] || !pkey[2] || !pkey[3] || !pkey[4] + || !pkey[5] || !pkey[6] || !pkey[7] || !pkey[8] || !pkey[9]) + return G10ERR_BAD_MPI; + + if (DBG_CIPHER) + { + log_debug ("ECC encrypt.\n"); + } + pk.E.p_ = pkey[0]; + pk.E.a_ = pkey[1]; + pk.E.b_ = pkey[2]; + pk.E.G.x_ = pkey[3]; + pk.E.G.y_ = pkey[4]; + pk.E.G.z_ = pkey[5]; + pk.E.n_ = pkey[6]; + pk.Q.x_ = pkey[7]; + pk.Q.y_ = pkey[8]; + pk.Q.z_ = pkey[9]; + + R.x_ = resarr[0] = mpi_alloc (mpi_get_nlimbs (pk.Q.x_)); + R.y_ = resarr[1] = mpi_alloc (mpi_get_nlimbs (pk.Q.y_)); + R.z_ = resarr[2] = mpi_alloc (mpi_get_nlimbs (pk.Q.z_)); + resarr[3] = mpi_alloc (mpi_get_nlimbs (pk.E.p_)); + + doEncrypt (data, &pk, &R, resarr[3]); + + resarr[0] = mpi_copy (R.x_); + resarr[1] = mpi_copy (R.y_); + resarr[2] = mpi_copy (R.z_); + return 0; } int -ecc_sign( int algo, MPI *resarr, MPI data, MPI *skey ) +ecc_decrypt_FIXME (int algo, gcry_mpi_t * result, gcry_mpi_t * data, gcry_mpi_t * skey) { - ECC_secret_key sk; - - if( algo != PUBKEY_ALGO_ECC && algo != PUBKEY_ALGO_ECC_S ) - return G10ERR_PUBKEY_ALGO; - if( !data || !skey[0] || !skey[1] || !skey[2] || !skey[3] || !skey[4] || !skey[5] || !skey[6] || !skey[7] || !skey[8] || !skey[9] || !skey[10]) - return G10ERR_BAD_MPI; - - sk.E.p_ = skey[0]; - sk.E.a_ = skey[1]; - sk.E.b_ = skey[2]; - sk.E.G.x_ = skey[3]; - sk.E.G.y_ = skey[4]; - sk.E.G.z_ = skey[5]; - sk.E.n_ = skey[6]; - sk.Q.x_ = skey[7]; - sk.Q.y_ = skey[8]; - sk.Q.z_ = skey[9]; - sk.d = skey[10]; - - resarr[0] = mpi_alloc( mpi_get_nlimbs( sk.E.p_ ) ); - resarr[1] = mpi_alloc( mpi_get_nlimbs( sk.E.p_ ) ); - sign( data, &sk, &resarr[0], &resarr[1]); - return 0; + ECC_secret_key sk; + point R; + + if (algo != PUBKEY_ALGO_ECC && algo != PUBKEY_ALGO_ECC_E) + return G10ERR_PUBKEY_ALGO; + if (!data[0] || !data[1] || !data[2] || !data[3] || !skey[0] || !skey[1] + || !skey[2] || !skey[3] || !skey[4] || !skey[5] || !skey[6] || !skey[7] + || !skey[8] || !skey[9] || !skey[10]) + return G10ERR_BAD_MPI; + + if (DBG_CIPHER) + { + log_debug ("ECC decrypt.\n"); + } + R.x_ = data[0]; + R.y_ = data[1]; + R.z_ = data[2]; + sk.E.p_ = skey[0]; + sk.E.a_ = skey[1]; + sk.E.b_ = skey[2]; + sk.E.G.x_ = skey[3]; + sk.E.G.y_ = skey[4]; + sk.E.G.z_ = skey[5]; + sk.E.n_ = skey[6]; + sk.Q.x_ = skey[7]; + sk.Q.y_ = skey[8]; + sk.Q.z_ = skey[9]; + sk.d = skey[10]; + + *result = mpi_alloc_secure (mpi_get_nlimbs (sk.E.p_)); + *result = decrypt (*result, &sk, R, data[3]); + return 0; } +#endif /*0*/ -int -ecc_verify( int algo, MPI hash, MPI *data, MPI *pkey ) +static gcry_err_code_t +ecc_sign (int algo, gcry_mpi_t *resarr, gcry_mpi_t data, gcry_mpi_t *skey) { - ECC_public_key pk; - - if( algo != PUBKEY_ALGO_ECC && algo != PUBKEY_ALGO_ECC_S ) - return G10ERR_PUBKEY_ALGO; - if( !data[0] || !data[1] || !hash || !pkey[0] || !pkey[1] || !pkey[2] || !pkey[3] || !pkey[4] || !pkey[5] || !pkey[6] || !pkey[7] || !pkey[8] || !pkey[9]) - return G10ERR_BAD_MPI; - - if( DBG_CIPHER ){log_info("ECC verify.\n");} - pk.E.p_ = pkey[0]; - pk.E.a_ = pkey[1]; - pk.E.b_ = pkey[2]; - pk.E.G.x_ = pkey[3]; - pk.E.G.y_ = pkey[4]; - pk.E.G.z_ = pkey[5]; - pk.E.n_ = pkey[6]; - pk.Q.x_ = pkey[7]; - pk.Q.y_ = pkey[8]; - pk.Q.z_ = pkey[9]; - - if( !verify( hash, &pk, data[0], data[1]) ) - return G10ERR_BAD_SIGN; - return 0; + ECC_secret_key sk; + + (void)algo; + + if (!data || !skey[0] || !skey[1] || !skey[2] || !skey[3] || !skey[4] + || !skey[5] || !skey[6] || !skey[7] || !skey[8] || !skey[9] + || !skey[10]) + return GPG_ERR_BAD_MPI; + + sk.E.p_ = skey[0]; + sk.E.a_ = skey[1]; + sk.E.b_ = skey[2]; + sk.E.G.x_ = skey[3]; + sk.E.G.y_ = skey[4]; + sk.E.G.z_ = skey[5]; + sk.E.n_ = skey[6]; + sk.Q.x_ = skey[7]; + sk.Q.y_ = skey[8]; + sk.Q.z_ = skey[9]; + sk.d = skey[10]; + + resarr[0] = mpi_alloc (mpi_get_nlimbs (sk.E.p_)); + resarr[1] = mpi_alloc (mpi_get_nlimbs (sk.E.p_)); + sign (data, &sk, &resarr[0], &resarr[1]); + return 0; } +static gcry_err_code_t +ecc_verify (int algo, gcry_mpi_t hash, gcry_mpi_t *data, gcry_mpi_t *pkey, + int (*cmp)(void *, gcry_mpi_t), void *opaquev) +{ + ECC_public_key pk; + (void)algo; -unsigned int -ecc_get_nbits( int algo, MPI *pkey ) -{ - if ( !is_ECC(algo) ){ - return 0; - } - if( DBG_CIPHER ){log_info("ECC get nbits.\n");} - - if( DBG_CIPHER ) { - progress('\n'); - - log_mpidump("[ecc] p= ", pkey[0]); - log_mpidump("[ecc] a= ", pkey[1]); - log_mpidump("[ecc] b= ", pkey[2]); - log_mpidump("[ecc] Gx= ", pkey[3]); - log_mpidump("[ecc] Gy= ", pkey[4]); - log_mpidump("[ecc] Gz= ", pkey[5]); - log_mpidump("[ecc] n= ", pkey[6]); - log_mpidump("[ecc] Qx= ", pkey[7]); - log_mpidump("[ecc] Qy= ", pkey[8]); - log_mpidump("[ecc] Qz= ", pkey[9]); - } - - return mpi_get_nbits( pkey[0] ); + if (!data[0] || !data[1] || !hash || !pkey[0] || !pkey[1] || !pkey[2] + || !pkey[3] || !pkey[4] || !pkey[5] || !pkey[6] || !pkey[7] || !pkey[8] + || !pkey[9]) + return GPG_ERR_BAD_MPI; + + if (DBG_CIPHER) + { + log_debug ("ECC verify.\n"); + } + pk.E.p_ = pkey[0]; + pk.E.a_ = pkey[1]; + pk.E.b_ = pkey[2]; + pk.E.G.x_ = pkey[3]; + pk.E.G.y_ = pkey[4]; + pk.E.G.z_ = pkey[5]; + pk.E.n_ = pkey[6]; + pk.Q.x_ = pkey[7]; + pk.Q.y_ = pkey[8]; + pk.Q.z_ = pkey[9]; + + if (!verify (hash, &pk, data[0], data[1])) + return GPG_ERR_BAD_SIGNATURE; + return 0; } -const char * -ecc_get_info( int algo, int *npkey, int *nskey, int *nenc, int *nsig, int *use ) + + +static unsigned int +ecc_get_nbits (int algo, gcry_mpi_t *pkey) { - *npkey = 10; - *nskey = 11; - *nenc = 4; - *nsig = 2; - - if( DBG_CIPHER ){log_info("ECC get info.\n");} - switch( algo ) { - case PUBKEY_ALGO_ECC: - *use = PUBKEY_USAGE_SIG|PUBKEY_USAGE_ENC; - return "ECC"; - case PUBKEY_ALGO_ECC_S: - *use = PUBKEY_USAGE_SIG; - return "ECDSA"; - case PUBKEY_ALGO_ECC_E: - *use = PUBKEY_USAGE_ENC; - return "ECELG"; - default: *use = 0; return NULL; + (void)algo; + + if (DBG_CIPHER) + { + log_debug ("ECC get nbits.\n"); } + + if (DBG_CIPHER) + { + progress ('\n'); + + log_mpidump ("[ecc] p= ", pkey[0]); + log_mpidump ("[ecc] a= ", pkey[1]); + log_mpidump ("[ecc] b= ", pkey[2]); + log_mpidump ("[ecc] Gx= ", pkey[3]); + log_mpidump ("[ecc] Gy= ", pkey[4]); + log_mpidump ("[ecc] Gz= ", pkey[5]); + log_mpidump ("[ecc] n= ", pkey[6]); + log_mpidump ("[ecc] Qx= ", pkey[7]); + log_mpidump ("[ecc] Qy= ", pkey[8]); + log_mpidump ("[ecc] Qz= ", pkey[9]); + } + + return mpi_get_nbits (pkey[0]); } + + +static const char *ecdsa_names[] = + { + "ecdsa", + NULL, + }; + +gcry_pk_spec_t _gcry_pubkey_spec_ecdsa = + { + "ECDSA", ecdsa_names, + "pabxyznXYZ", "pabxyznXYZd", "", "rs", "pabxyznXYZ", + GCRY_PK_USAGE_SIGN, + ecc_generate, + ecc_check_secret_key, + NULL, + NULL, + ecc_sign, + ecc_verify, + ecc_get_nbits + }; + + + |