diff options
Diffstat (limited to 'package/utils/px5g/src/library/bignum.c')
| -rw-r--r-- | package/utils/px5g/src/library/bignum.c | 2010 |
1 files changed, 2010 insertions, 0 deletions
diff --git a/package/utils/px5g/src/library/bignum.c b/package/utils/px5g/src/library/bignum.c new file mode 100644 index 0000000000..8b7c12ff00 --- /dev/null +++ b/package/utils/px5g/src/library/bignum.c @@ -0,0 +1,2010 @@ +/* + * Multi-precision integer library + * + * Based on XySSL: Copyright (C) 2006-2008 Christophe Devine + * + * Copyright (C) 2009 Paul Bakker <polarssl_maintainer at polarssl dot org> + * + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * * Neither the names of PolarSSL or XySSL nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED + * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR + * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF + * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +/* + * This MPI implementation is based on: + * + * http://www.cacr.math.uwaterloo.ca/hac/about/chap14.pdf + * http://www.stillhq.com/extracted/gnupg-api/mpi/ + * http://math.libtomcrypt.com/files/tommath.pdf + */ + +#include "polarssl/config.h" + +#if defined(POLARSSL_BIGNUM_C) + +#include "polarssl/bignum.h" +#include "polarssl/bn_mul.h" + +#include <string.h> +#include <stdlib.h> +#include <stdarg.h> + +#define ciL ((int) sizeof(t_int)) /* chars in limb */ +#define biL (ciL << 3) /* bits in limb */ +#define biH (ciL << 2) /* half limb size */ + +/* + * Convert between bits/chars and number of limbs + */ +#define BITS_TO_LIMBS(i) (((i) + biL - 1) / biL) +#define CHARS_TO_LIMBS(i) (((i) + ciL - 1) / ciL) + +/* + * Initialize one or more mpi + */ +void mpi_init( mpi *X, ... ) +{ + va_list args; + + va_start( args, X ); + + while( X != NULL ) + { + X->s = 1; + X->n = 0; + X->p = NULL; + + X = va_arg( args, mpi* ); + } + + va_end( args ); +} + +/* + * Unallocate one or more mpi + */ +void mpi_free( mpi *X, ... ) +{ + va_list args; + + va_start( args, X ); + + while( X != NULL ) + { + if( X->p != NULL ) + { + memset( X->p, 0, X->n * ciL ); + free( X->p ); + } + + X->s = 1; + X->n = 0; + X->p = NULL; + + X = va_arg( args, mpi* ); + } + + va_end( args ); +} + +/* + * Enlarge to the specified number of limbs + */ +int mpi_grow( mpi *X, int nblimbs ) +{ + t_int *p; + + if( X->n < nblimbs ) + { + if( ( p = (t_int *) malloc( nblimbs * ciL ) ) == NULL ) + return( 1 ); + + memset( p, 0, nblimbs * ciL ); + + if( X->p != NULL ) + { + memcpy( p, X->p, X->n * ciL ); + memset( X->p, 0, X->n * ciL ); + free( X->p ); + } + + X->n = nblimbs; + X->p = p; + } + + return( 0 ); +} + +/* + * Copy the contents of Y into X + */ +int mpi_copy( mpi *X, mpi *Y ) +{ + int ret, i; + + if( X == Y ) + return( 0 ); + + for( i = Y->n - 1; i > 0; i-- ) + if( Y->p[i] != 0 ) + break; + i++; + + X->s = Y->s; + + MPI_CHK( mpi_grow( X, i ) ); + + memset( X->p, 0, X->n * ciL ); + memcpy( X->p, Y->p, i * ciL ); + +cleanup: + + return( ret ); +} + +/* + * Swap the contents of X and Y + */ +void mpi_swap( mpi *X, mpi *Y ) +{ + mpi T; + + memcpy( &T, X, sizeof( mpi ) ); + memcpy( X, Y, sizeof( mpi ) ); + memcpy( Y, &T, sizeof( mpi ) ); +} + +/* + * Set value from integer + */ +int mpi_lset( mpi *X, int z ) +{ + int ret; + + MPI_CHK( mpi_grow( X, 1 ) ); + memset( X->p, 0, X->n * ciL ); + + X->p[0] = ( z < 0 ) ? -z : z; + X->s = ( z < 0 ) ? -1 : 1; + +cleanup: + + return( ret ); +} + +/* + * Return the number of least significant bits + */ +int mpi_lsb( mpi *X ) +{ + int i, j, count = 0; + + for( i = 0; i < X->n; i++ ) + for( j = 0; j < (int) biL; j++, count++ ) + if( ( ( X->p[i] >> j ) & 1 ) != 0 ) + return( count ); + + return( 0 ); +} + +/* + * Return the number of most significant bits + */ +int mpi_msb( mpi *X ) +{ + int i, j; + + for( i = X->n - 1; i > 0; i-- ) + if( X->p[i] != 0 ) + break; + + for( j = biL - 1; j >= 0; j-- ) + if( ( ( X->p[i] >> j ) & 1 ) != 0 ) + break; + + return( ( i * biL ) + j + 1 ); +} + +/* + * Return the total size in bytes + */ +int mpi_size( mpi *X ) +{ + return( ( mpi_msb( X ) + 7 ) >> 3 ); +} + +/* + * Convert an ASCII character to digit value + */ +static int mpi_get_digit( t_int *d, int radix, char c ) +{ + *d = 255; + + if( c >= 0x30 && c <= 0x39 ) *d = c - 0x30; + if( c >= 0x41 && c <= 0x46 ) *d = c - 0x37; + if( c >= 0x61 && c <= 0x66 ) *d = c - 0x57; + + if( *d >= (t_int) radix ) + return( POLARSSL_ERR_MPI_INVALID_CHARACTER ); + + return( 0 ); +} + +/* + * Import from an ASCII string + */ +int mpi_read_string( mpi *X, int radix, char *s ) +{ + int ret, i, j, n; + t_int d; + mpi T; + + if( radix < 2 || radix > 16 ) + return( POLARSSL_ERR_MPI_BAD_INPUT_DATA ); + + mpi_init( &T, NULL ); + + if( radix == 16 ) + { + n = BITS_TO_LIMBS( strlen( s ) << 2 ); + + MPI_CHK( mpi_grow( X, n ) ); + MPI_CHK( mpi_lset( X, 0 ) ); + + for( i = strlen( s ) - 1, j = 0; i >= 0; i--, j++ ) + { + if( i == 0 && s[i] == '-' ) + { + X->s = -1; + break; + } + + MPI_CHK( mpi_get_digit( &d, radix, s[i] ) ); + X->p[j / (2 * ciL)] |= d << ( (j % (2 * ciL)) << 2 ); + } + } + else + { + MPI_CHK( mpi_lset( X, 0 ) ); + + for( i = 0; i < (int) strlen( s ); i++ ) + { + if( i == 0 && s[i] == '-' ) + { + X->s = -1; + continue; + } + + MPI_CHK( mpi_get_digit( &d, radix, s[i] ) ); + MPI_CHK( mpi_mul_int( &T, X, radix ) ); + MPI_CHK( mpi_add_int( X, &T, d ) ); + } + } + +cleanup: + + mpi_free( &T, NULL ); + + return( ret ); +} + +/* + * Helper to write the digits high-order first + */ +static int mpi_write_hlp( mpi *X, int radix, char **p ) +{ + int ret; + t_int r; + + if( radix < 2 || radix > 16 ) + return( POLARSSL_ERR_MPI_BAD_INPUT_DATA ); + + MPI_CHK( mpi_mod_int( &r, X, radix ) ); + MPI_CHK( mpi_div_int( X, NULL, X, radix ) ); + + if( mpi_cmp_int( X, 0 ) != 0 ) + MPI_CHK( mpi_write_hlp( X, radix, p ) ); + + if( r < 10 ) + *(*p)++ = (char)( r + 0x30 ); + else + *(*p)++ = (char)( r + 0x37 ); + +cleanup: + + return( ret ); +} + +/* + * Export into an ASCII string + */ +int mpi_write_string( mpi *X, int radix, char *s, int *slen ) +{ + int ret = 0, n; + char *p; + mpi T; + + if( radix < 2 || radix > 16 ) + return( POLARSSL_ERR_MPI_BAD_INPUT_DATA ); + + n = mpi_msb( X ); + if( radix >= 4 ) n >>= 1; + if( radix >= 16 ) n >>= 1; + n += 3; + + if( *slen < n ) + { + *slen = n; + return( POLARSSL_ERR_MPI_BUFFER_TOO_SMALL ); + } + + p = s; + mpi_init( &T, NULL ); + + if( X->s == -1 ) + *p++ = '-'; + + if( radix == 16 ) + { + int c, i, j, k; + + for( i = X->n - 1, k = 0; i >= 0; i-- ) + { + for( j = ciL - 1; j >= 0; j-- ) + { + c = ( X->p[i] >> (j << 3) ) & 0xFF; + + if( c == 0 && k == 0 && (i + j) != 0 ) + continue; + + p += sprintf( p, "%02X", c ); + k = 1; + } + } + } + else + { + MPI_CHK( mpi_copy( &T, X ) ); + MPI_CHK( mpi_write_hlp( &T, radix, &p ) ); + } + + *p++ = '\0'; + *slen = p - s; + +cleanup: + + mpi_free( &T, NULL ); + + return( ret ); +} + +/* + * Read X from an opened file + */ +int mpi_read_file( mpi *X, int radix, FILE *fin ) +{ + t_int d; + int slen; + char *p; + char s[1024]; + + memset( s, 0, sizeof( s ) ); + if( fgets( s, sizeof( s ) - 1, fin ) == NULL ) + return( POLARSSL_ERR_MPI_FILE_IO_ERROR ); + + slen = strlen( s ); + if( s[slen - 1] == '\n' ) { slen--; s[slen] = '\0'; } + if( s[slen - 1] == '\r' ) { slen--; s[slen] = '\0'; } + + p = s + slen; + while( --p >= s ) + if( mpi_get_digit( &d, radix, *p ) != 0 ) + break; + + return( mpi_read_string( X, radix, p + 1 ) ); +} + +/* + * Write X into an opened file (or stdout if fout == NULL) + */ +int mpi_write_file( char *p, mpi *X, int radix, FILE *fout ) +{ + int n, ret; + size_t slen; + size_t plen; + char s[1024]; + + n = sizeof( s ); + memset( s, 0, n ); + n -= 2; + + MPI_CHK( mpi_write_string( X, radix, s, (int *) &n ) ); + + if( p == NULL ) p = ""; + + plen = strlen( p ); + slen = strlen( s ); + s[slen++] = '\r'; + s[slen++] = '\n'; + + if( fout != NULL ) + { + if( fwrite( p, 1, plen, fout ) != plen || + fwrite( s, 1, slen, fout ) != slen ) + return( POLARSSL_ERR_MPI_FILE_IO_ERROR ); + } + else + printf( "%s%s", p, s ); + +cleanup: + + return( ret ); +} + +/* + * Import X from unsigned binary data, big endian + */ +int mpi_read_binary( mpi *X, unsigned char *buf, int buflen ) +{ + int ret, i, j, n; + + for( n = 0; n < buflen; n++ ) + if( buf[n] != 0 ) + break; + + MPI_CHK( mpi_grow( X, CHARS_TO_LIMBS( buflen - n ) ) ); + MPI_CHK( mpi_lset( X, 0 ) ); + + for( i = buflen - 1, j = 0; i >= n; i--, j++ ) + X->p[j / ciL] |= ((t_int) buf[i]) << ((j % ciL) << 3); + +cleanup: + + return( ret ); +} + +/* + * Export X into unsigned binary data, big endian + */ +int mpi_write_binary( mpi *X, unsigned char *buf, int buflen ) +{ + int i, j, n; + + n = mpi_size( X ); + + if( buflen < n ) + return( POLARSSL_ERR_MPI_BUFFER_TOO_SMALL ); + + memset( buf, 0, buflen ); + + for( i = buflen - 1, j = 0; n > 0; i--, j++, n-- ) + buf[i] = (unsigned char)( X->p[j / ciL] >> ((j % ciL) << 3) ); + + return( 0 ); +} + +/* + * Left-shift: X <<= count + */ +int mpi_shift_l( mpi *X, int count ) +{ + int ret, i, v0, t1; + t_int r0 = 0, r1; + + v0 = count / (biL ); + t1 = count & (biL - 1); + + i = mpi_msb( X ) + count; + + if( X->n * (int) biL < i ) + MPI_CHK( mpi_grow( X, BITS_TO_LIMBS( i ) ) ); + + ret = 0; + + /* + * shift by count / limb_size + */ + if( v0 > 0 ) + { + for( i = X->n - 1; i >= v0; i-- ) + X->p[i] = X->p[i - v0]; + + for( ; i >= 0; i-- ) + X->p[i] = 0; + } + + /* + * shift by count % limb_size + */ + if( t1 > 0 ) + { + for( i = v0; i < X->n; i++ ) + { + r1 = X->p[i] >> (biL - t1); + X->p[i] <<= t1; + X->p[i] |= r0; + r0 = r1; + } + } + +cleanup: + + return( ret ); +} + +/* + * Right-shift: X >>= count + */ +int mpi_shift_r( mpi *X, int count ) +{ + int i, v0, v1; + t_int r0 = 0, r1; + + v0 = count / biL; + v1 = count & (biL - 1); + + /* + * shift by count / limb_size + */ + if( v0 > 0 ) + { + for( i = 0; i < X->n - v0; i++ ) + X->p[i] = X->p[i + v0]; + + for( ; i < X->n; i++ ) + X->p[i] = 0; + } + + /* + * shift by count % limb_size + */ + if( v1 > 0 ) + { + for( i = X->n - 1; i >= 0; i-- ) + { + r1 = X->p[i] << (biL - v1); + X->p[i] >>= v1; + X->p[i] |= r0; + r0 = r1; + } + } + + return( 0 ); +} + +/* + * Compare unsigned values + */ +int mpi_cmp_abs( mpi *X, mpi *Y ) +{ + int i, j; + + for( i = X->n - 1; i >= 0; i-- ) + if( X->p[i] != 0 ) + break; + + for( j = Y->n - 1; j >= 0; j-- ) + if( Y->p[j] != 0 ) + break; + + if( i < 0 && j < 0 ) + return( 0 ); + + if( i > j ) return( 1 ); + if( j > i ) return( -1 ); + + for( ; i >= 0; i-- ) + { + if( X->p[i] > Y->p[i] ) return( 1 ); + if( X->p[i] < Y->p[i] ) return( -1 ); + } + + return( 0 ); +} + +/* + * Compare signed values + */ +int mpi_cmp_mpi( mpi *X, mpi *Y ) +{ + int i, j; + + for( i = X->n - 1; i >= 0; i-- ) + if( X->p[i] != 0 ) + break; + + for( j = Y->n - 1; j >= 0; j-- ) + if( Y->p[j] != 0 ) + break; + + if( i < 0 && j < 0 ) + return( 0 ); + + if( i > j ) return( X->s ); + if( j > i ) return( -X->s ); + + if( X->s > 0 && Y->s < 0 ) return( 1 ); + if( Y->s > 0 && X->s < 0 ) return( -1 ); + + for( ; i >= 0; i-- ) + { + if( X->p[i] > Y->p[i] ) return( X->s ); + if( X->p[i] < Y->p[i] ) return( -X->s ); + } + + return( 0 ); +} + +/* + * Compare signed values + */ +int mpi_cmp_int( mpi *X, int z ) +{ + mpi Y; + t_int p[1]; + + *p = ( z < 0 ) ? -z : z; + Y.s = ( z < 0 ) ? -1 : 1; + Y.n = 1; + Y.p = p; + + return( mpi_cmp_mpi( X, &Y ) ); +} + +/* + * Unsigned addition: X = |A| + |B| (HAC 14.7) + */ +int mpi_add_abs( mpi *X, mpi *A, mpi *B ) +{ + int ret, i, j; + t_int *o, *p, c; + + if( X == B ) + { + mpi *T = A; A = X; B = T; + } + + if( X != A ) + MPI_CHK( mpi_copy( X, A ) ); + + for( j = B->n - 1; j >= 0; j-- ) + if( B->p[j] != 0 ) + break; + + MPI_CHK( mpi_grow( X, j + 1 ) ); + + o = B->p; p = X->p; c = 0; + + for( i = 0; i <= j; i++, o++, p++ ) + { + *p += c; c = ( *p < c ); + *p += *o; c += ( *p < *o ); + } + + while( c != 0 ) + { + if( i >= X->n ) + { + MPI_CHK( mpi_grow( X, i + 1 ) ); + p = X->p + i; + } + + *p += c; c = ( *p < c ); i++; + } + +cleanup: + + return( ret ); +} + +/* + * Helper for mpi substraction + */ +static void mpi_sub_hlp( int n, t_int *s, t_int *d ) +{ + int i; + t_int c, z; + + for( i = c = 0; i < n; i++, s++, d++ ) + { + z = ( *d < c ); *d -= c; + c = ( *d < *s ) + z; *d -= *s; + } + + while( c != 0 ) + { + z = ( *d < c ); *d -= c; + c = z; i++; d++; + } +} + +/* + * Unsigned substraction: X = |A| - |B| (HAC 14.9) + */ +int mpi_sub_abs( mpi *X, mpi *A, mpi *B ) +{ + mpi TB; + int ret, n; + + if( mpi_cmp_abs( A, B ) < 0 ) + return( POLARSSL_ERR_MPI_NEGATIVE_VALUE ); + + mpi_init( &TB, NULL ); + + if( X == B ) + { + MPI_CHK( mpi_copy( &TB, B ) ); + B = &TB; + } + + if( X != A ) + MPI_CHK( mpi_copy( X, A ) ); + + ret = 0; + + for( n = B->n - 1; n >= 0; n-- ) + if( B->p[n] != 0 ) + break; + + mpi_sub_hlp( n + 1, B->p, X->p ); + +cleanup: + + mpi_free( &TB, NULL ); + + return( ret ); +} + +/* + * Signed addition: X = A + B + */ +int mpi_add_mpi( mpi *X, mpi *A, mpi *B ) +{ + int ret, s = A->s; + + if( A->s * B->s < 0 ) + { + if( mpi_cmp_abs( A, B ) >= 0 ) + { + MPI_CHK( mpi_sub_abs( X, A, B ) ); + X->s = s; + } + else + { + MPI_CHK( mpi_sub_abs( X, B, A ) ); + X->s = -s; + } + } + else + { + MPI_CHK( mpi_add_abs( X, A, B ) ); + X->s = s; + } + +cleanup: + + return( ret ); +} + +/* + * Signed substraction: X = A - B + */ +int mpi_sub_mpi( mpi *X, mpi *A, mpi *B ) +{ + int ret, s = A->s; + + if( A->s * B->s > 0 ) + { + if( mpi_cmp_abs( A, B ) >= 0 ) + { + MPI_CHK( mpi_sub_abs( X, A, B ) ); + X->s = s; + } + else + { + MPI_CHK( mpi_sub_abs( X, B, A ) ); + X->s = -s; + } + } + else + { + MPI_CHK( mpi_add_abs( X, A, B ) ); + X->s = s; + } + +cleanup: + + return( ret ); +} + +/* + * Signed addition: X = A + b + */ +int mpi_add_int( mpi *X, mpi *A, int b ) +{ + mpi _B; + t_int p[1]; + + p[0] = ( b < 0 ) ? -b : b; + _B.s = ( b < 0 ) ? -1 : 1; + _B.n = 1; + _B.p = p; + + return( mpi_add_mpi( X, A, &_B ) ); +} + +/* + * Signed substraction: X = A - b + */ +int mpi_sub_int( mpi *X, mpi *A, int b ) +{ + mpi _B; + t_int p[1]; + + p[0] = ( b < 0 ) ? -b : b; + _B.s = ( b < 0 ) ? -1 : 1; + _B.n = 1; + _B.p = p; + + return( mpi_sub_mpi( X, A, &_B ) ); +} + +/* + * Helper for mpi multiplication + */ +static void mpi_mul_hlp( int i, t_int *s, t_int *d, t_int b ) +{ + t_int c = 0, t = 0; + +#if defined(MULADDC_HUIT) + for( ; i >= 8; i -= 8 ) + { + MULADDC_INIT + MULADDC_HUIT + MULADDC_STOP + } + + for( ; i > 0; i-- ) + { + MULADDC_INIT + MULADDC_CORE + MULADDC_STOP + } +#else + for( ; i >= 16; i -= 16 ) + { + MULADDC_INIT + MULADDC_CORE MULADDC_CORE + MULADDC_CORE MULADDC_CORE + MULADDC_CORE MULADDC_CORE + MULADDC_CORE MULADDC_CORE + + MULADDC_CORE MULADDC_CORE + MULADDC_CORE MULADDC_CORE + MULADDC_CORE MULADDC_CORE + MULADDC_CORE MULADDC_CORE + MULADDC_STOP + } + + for( ; i >= 8; i -= 8 ) + { + MULADDC_INIT + MULADDC_CORE MULADDC_CORE + MULADDC_CORE MULADDC_CORE + + MULADDC_CORE MULADDC_CORE + MULADDC_CORE MULADDC_CORE + MULADDC_STOP + } + + for( ; i > 0; i-- ) + { + MULADDC_INIT + MULADDC_CORE + MULADDC_STOP + } +#endif + + t++; + + do { + *d += c; c = ( *d < c ); d++; + } + while( c != 0 ); +} + +/* + * Baseline multiplication: X = A * B (HAC 14.12) + */ +int mpi_mul_mpi( mpi *X, mpi *A, mpi *B ) +{ + int ret, i, j; + mpi TA, TB; + + mpi_init( &TA, &TB, NULL ); + + if( X == A ) { MPI_CHK( mpi_copy( &TA, A ) ); A = &TA; } + if( X == B ) { MPI_CHK( mpi_copy( &TB, B ) ); B = &TB; } + + for( i = A->n - 1; i >= 0; i-- ) + if( A->p[i] != 0 ) + break; + + for( j = B->n - 1; j >= 0; j-- ) + if( B->p[j] != 0 ) + break; + + MPI_CHK( mpi_grow( X, i + j + 2 ) ); + MPI_CHK( mpi_lset( X, 0 ) ); + + for( i++; j >= 0; j-- ) + mpi_mul_hlp( i, A->p, X->p + j, B->p[j] ); + + X->s = A->s * B->s; + +cleanup: + + mpi_free( &TB, &TA, NULL ); + + return( ret ); +} + +/* + * Baseline multiplication: X = A * b + */ +int mpi_mul_int( mpi *X, mpi *A, t_int b ) +{ + mpi _B; + t_int p[1]; + + _B.s = 1; + _B.n = 1; + _B.p = p; + p[0] = b; + + return( mpi_mul_mpi( X, A, &_B ) ); +} + +/* + * Division by mpi: A = Q * B + R (HAC 14.20) + */ +int mpi_div_mpi( mpi *Q, mpi *R, mpi *A, mpi *B ) +{ + int ret, i, n, t, k; + mpi X, Y, Z, T1, T2; + + if( mpi_cmp_int( B, 0 ) == 0 ) + return( POLARSSL_ERR_MPI_DIVISION_BY_ZERO ); + + mpi_init( &X, &Y, &Z, &T1, &T2, NULL ); + + if( mpi_cmp_abs( A, B ) < 0 ) + { + if( Q != NULL ) MPI_CHK( mpi_lset( Q, 0 ) ); + if( R != NULL ) MPI_CHK( mpi_copy( R, A ) ); + return( 0 ); + } + + MPI_CHK( mpi_copy( &X, A ) ); + MPI_CHK( mpi_copy( &Y, B ) ); + X.s = Y.s = 1; + + MPI_CHK( mpi_grow( &Z, A->n + 2 ) ); + MPI_CHK( mpi_lset( &Z, 0 ) ); + MPI_CHK( mpi_grow( &T1, 2 ) ); + MPI_CHK( mpi_grow( &T2, 3 ) ); + + k = mpi_msb( &Y ) % biL; + if( k < (int) biL - 1 ) + { + k = biL - 1 - k; + MPI_CHK( mpi_shift_l( &X, k ) ); + MPI_CHK( mpi_shift_l( &Y, k ) ); + } + else k = 0; + + n = X.n - 1; + t = Y.n - 1; + mpi_shift_l( &Y, biL * (n - t) ); + + while( mpi_cmp_mpi( &X, &Y ) >= 0 ) + { + Z.p[n - t]++; + mpi_sub_mpi( &X, &X, &Y ); + } + mpi_shift_r( &Y, biL * (n - t) ); + + for( i = n; i > t ; i-- ) + { + if( X.p[i] >= Y.p[t] ) + Z.p[i - t - 1] = ~0; + else + { +#if defined(POLARSSL_HAVE_LONGLONG) + t_dbl r; + + r = (t_dbl) X.p[i] << biL; + r |= (t_dbl) X.p[i - 1]; + r /= Y.p[t]; + if( r > ((t_dbl) 1 << biL) - 1) + r = ((t_dbl) 1 << biL) - 1; + + Z.p[i - t - 1] = (t_int) r; +#else + /* + * __udiv_qrnnd_c, from gmp/longlong.h + */ + t_int q0, q1, r0, r1; + t_int d0, d1, d, m; + + d = Y.p[t]; + d0 = ( d << biH ) >> biH; + d1 = ( d >> biH ); + + q1 = X.p[i] / d1; + r1 = X.p[i] - d1 * q1; + r1 <<= biH; + r1 |= ( X.p[i - 1] >> biH ); + + m = q1 * d0; + if( r1 < m ) + { + q1--, r1 += d; + while( r1 >= d && r1 < m ) + q1--, r1 += d; + } + r1 -= m; + + q0 = r1 / d1; + r0 = r1 - d1 * q0; + r0 <<= biH; + r0 |= ( X.p[i - 1] << biH ) >> biH; + + m = q0 * d0; + if( r0 < m ) + { + q0--, r0 += d; + while( r0 >= d && r0 < m ) + q0--, r0 += d; + } + r0 -= m; + + Z.p[i - t - 1] = ( q1 << biH ) | q0; +#endif + } + + Z.p[i - t - 1]++; + do + { + Z.p[i - t - 1]--; + + MPI_CHK( mpi_lset( &T1, 0 ) ); + T1.p[0] = (t < 1) ? 0 : Y.p[t - 1]; + T1.p[1] = Y.p[t]; + MPI_CHK( mpi_mul_int( &T1, &T1, Z.p[i - t - 1] ) ); + + MPI_CHK( mpi_lset( &T2, 0 ) ); + T2.p[0] = (i < 2) ? 0 : X.p[i - 2]; + T2.p[1] = (i < 1) ? 0 : X.p[i - 1]; + T2.p[2] = X.p[i]; + } + while( mpi_cmp_mpi( &T1, &T2 ) > 0 ); + + MPI_CHK( mpi_mul_int( &T1, &Y, Z.p[i - t - 1] ) ); + MPI_CHK( mpi_shift_l( &T1, biL * (i - t - 1) ) ); + MPI_CHK( mpi_sub_mpi( &X, &X, &T1 ) ); + + if( mpi_cmp_int( &X, 0 ) < 0 ) + { + MPI_CHK( mpi_copy( &T1, &Y ) ); + MPI_CHK( mpi_shift_l( &T1, biL * (i - t - 1) ) ); + MPI_CHK( mpi_add_mpi( &X, &X, &T1 ) ); + Z.p[i - t - 1]--; + } + } + + if( Q != NULL ) + { + mpi_copy( Q, &Z ); + Q->s = A->s * B->s; + } + + if( R != NULL ) + { + mpi_shift_r( &X, k ); + mpi_copy( R, &X ); + + R->s = A->s; + if( mpi_cmp_int( R, 0 ) == 0 ) + R->s = 1; + } + +cleanup: + + mpi_free( &X, &Y, &Z, &T1, &T2, NULL ); + + return( ret ); +} + +/* + * Division by int: A = Q * b + R + * + * Returns 0 if successful + * 1 if memory allocation failed + * POLARSSL_ERR_MPI_DIVISION_BY_ZERO if b == 0 + */ +int mpi_div_int( mpi *Q, mpi *R, mpi *A, int b ) +{ + mpi _B; + t_int p[1]; + + p[0] = ( b < 0 ) ? -b : b; + _B.s = ( b < 0 ) ? -1 : 1; + _B.n = 1; + _B.p = p; + + return( mpi_div_mpi( Q, R, A, &_B ) ); +} + +/* + * Modulo: R = A mod B + */ +int mpi_mod_mpi( mpi *R, mpi *A, mpi *B ) +{ + int ret; + + MPI_CHK( mpi_div_mpi( NULL, R, A, B ) ); + + while( mpi_cmp_int( R, 0 ) < 0 ) + MPI_CHK( mpi_add_mpi( R, R, B ) ); + + while( mpi_cmp_mpi( R, B ) >= 0 ) + MPI_CHK( mpi_sub_mpi( R, R, B ) ); + +cleanup: + + return( ret ); +} + +/* + * Modulo: r = A mod b + */ +int mpi_mod_int( t_int *r, mpi *A, int b ) +{ + int i; + t_int x, y, z; + + if( b == 0 ) + return( POLARSSL_ERR_MPI_DIVISION_BY_ZERO ); + + if( b < 0 ) + b = -b; + + /* + * handle trivial cases + */ + if( b == 1 ) + { + *r = 0; + return( 0 ); + } + + if( b == 2 ) + { + *r = A->p[0] & 1; + return( 0 ); + } + + /* + * general case + */ + for( i = A->n - 1, y = 0; i >= 0; i-- ) + { + x = A->p[i]; + y = ( y << biH ) | ( x >> biH ); + z = y / b; + y -= z * b; + + x <<= biH; + y = ( y << biH ) | ( x >> biH ); + z = y / b; + y -= z * b; + } + + *r = y; + + return( 0 ); +} + +/* + * Fast Montgomery initialization (thanks to Tom St Denis) + */ +static void mpi_montg_init( t_int *mm, mpi *N ) +{ + t_int x, m0 = N->p[0]; + + x = m0; + x += ( ( m0 + 2 ) & 4 ) << 1; + x *= ( 2 - ( m0 * x ) ); + + if( biL >= 16 ) x *= ( 2 - ( m0 * x ) ); + if( biL >= 32 ) x *= ( 2 - ( m0 * x ) ); + if( biL >= 64 ) x *= ( 2 - ( m0 * x ) ); + + *mm = ~x + 1; +} + +/* + * Montgomery multiplication: A = A * B * R^-1 mod N (HAC 14.36) + */ +static void mpi_montmul( mpi *A, mpi *B, mpi *N, t_int mm, mpi *T ) +{ + int i, n, m; + t_int u0, u1, *d; + + memset( T->p, 0, T->n * ciL ); + + d = T->p; + n = N->n; + m = ( B->n < n ) ? B->n : n; + + for( i = 0; i < n; i++ ) + { + /* + * T = (T + u0*B + u1*N) / 2^biL + */ + u0 = A->p[i]; + u1 = ( d[0] + u0 * B->p[0] ) * mm; + + mpi_mul_hlp( m, B->p, d, u0 ); + mpi_mul_hlp( n, N->p, d, u1 ); + + *d++ = u0; d[n + 1] = 0; + } + + memcpy( A->p, d, (n + 1) * ciL ); + + if( mpi_cmp_abs( A, N ) >= 0 ) + mpi_sub_hlp( n, N->p, A->p ); + else + /* prevent timing attacks */ + mpi_sub_hlp( n, A->p, T->p ); +} + +/* + * Montgomery reduction: A = A * R^-1 mod N + */ +static void mpi_montred( mpi *A, mpi *N, t_int mm, mpi *T ) +{ + t_int z = 1; + mpi U; + + U.n = U.s = z; + U.p = &z; + + mpi_montmul( A, &U, N, mm, T ); +} + +/* + * Sliding-window exponentiation: X = A^E mod N (HAC 14.85) + */ +int mpi_exp_mod( mpi *X, mpi *A, mpi *E, mpi *N, mpi *_RR ) +{ + int ret, i, j, wsize, wbits; + int bufsize, nblimbs, nbits; + t_int ei, mm, state; + mpi RR, T, W[64]; + + if( mpi_cmp_int( N, 0 ) < 0 || ( N->p[0] & 1 ) == 0 ) + return( POLARSSL_ERR_MPI_BAD_INPUT_DATA ); + + /* + * Init temps and window size + */ + mpi_montg_init( &mm, N ); + mpi_init( &RR, &T, NULL ); + memset( W, 0, sizeof( W ) ); + + i = mpi_msb( E ); + + wsize = ( i > 671 ) ? 6 : ( i > 239 ) ? 5 : + ( i > 79 ) ? 4 : ( i > 23 ) ? 3 : 1; + + j = N->n + 1; + MPI_CHK( mpi_grow( X, j ) ); + MPI_CHK( mpi_grow( &W[1], j ) ); + MPI_CHK( mpi_grow( &T, j * 2 ) ); + + /* + * If 1st call, pre-compute R^2 mod N + */ + if( _RR == NULL || _RR->p == NULL ) + { + MPI_CHK( mpi_lset( &RR, 1 ) ); + MPI_CHK( mpi_shift_l( &RR, N->n * 2 * biL ) ); + MPI_CHK( mpi_mod_mpi( &RR, &RR, N ) ); + + if( _RR != NULL ) + memcpy( _RR, &RR, sizeof( mpi ) ); + } + else + memcpy( &RR, _RR, sizeof( mpi ) ); + + /* + * W[1] = A * R^2 * R^-1 mod N = A * R mod N + */ + if( mpi_cmp_mpi( A, N ) >= 0 ) + mpi_mod_mpi( &W[1], A, N ); + else mpi_copy( &W[1], A ); + + mpi_montmul( &W[1], &RR, N, mm, &T ); + + /* + * X = R^2 * R^-1 mod N = R mod N + */ + MPI_CHK( mpi_copy( X, &RR ) ); + mpi_montred( X, N, mm, &T ); + + if( wsize > 1 ) + { + /* + * W[1 << (wsize - 1)] = W[1] ^ (wsize - 1) + */ + j = 1 << (wsize - 1); + + MPI_CHK( mpi_grow( &W[j], N->n + 1 ) ); + MPI_CHK( mpi_copy( &W[j], &W[1] ) ); + + for( i = 0; i < wsize - 1; i++ ) + mpi_montmul( &W[j], &W[j], N, mm, &T ); + + /* + * W[i] = W[i - 1] * W[1] + */ + for( i = j + 1; i < (1 << wsize); i++ ) + { + MPI_CHK( mpi_grow( &W[i], N->n + 1 ) ); + MPI_CHK( mpi_copy( &W[i], &W[i - 1] ) ); + + mpi_montmul( &W[i], &W[1], N, mm, &T ); + } + } + + nblimbs = E->n; + bufsize = 0; + nbits = 0; + wbits = 0; + state = 0; + + while( 1 ) + { + if( bufsize == 0 ) + { + if( nblimbs-- == 0 ) + break; + + bufsize = sizeof( t_int ) << 3; + } + + bufsize--; + + ei = (E->p[nblimbs] >> bufsize) & 1; + + /* + * skip leading 0s + */ + if( ei == 0 && state == 0 ) + continue; + + if( ei == 0 && state == 1 ) + { + /* + * out of window, square X + */ + mpi_montmul( X, X, N, mm, &T ); + continue; + } + + /* + * add ei to current window + */ + state = 2; + + nbits++; + wbits |= (ei << (wsize - nbits)); + + if( nbits == wsize ) + { + /* + * X = X^wsize R^-1 mod N + */ + for( i = 0; i < wsize; i++ ) + mpi_montmul( X, X, N, mm, &T ); + + /* + * X = X * W[wbits] R^-1 mod N + */ + mpi_montmul( X, &W[wbits], N, mm, &T ); + + state--; + nbits = 0; + wbits = 0; + } + } + + /* + * process the remaining bits + */ + for( i = 0; i < nbits; i++ ) + { + mpi_montmul( X, X, N, mm, &T ); + + wbits <<= 1; + + if( (wbits & (1 << wsize)) != 0 ) + mpi_montmul( X, &W[1], N, mm, &T ); + } + + /* + * X = A^E * R * R^-1 mod N = A^E mod N + */ + mpi_montred( X, N, mm, &T ); + +cleanup: + + for( i = (1 << (wsize - 1)); i < (1 << wsize); i++ ) + mpi_free( &W[i], NULL ); + + if( _RR != NULL ) + mpi_free( &W[1], &T, NULL ); + else mpi_free( &W[1], &T, &RR, NULL ); + + return( ret ); +} + +/* + * Greatest common divisor: G = gcd(A, B) (HAC 14.54) + */ +int mpi_gcd( mpi *G, mpi *A, mpi *B ) +{ + int ret, lz, lzt; + mpi TG, TA, TB; + + mpi_init( &TG, &TA, &TB, NULL ); + + MPI_CHK( mpi_copy( &TA, A ) ); + MPI_CHK( mpi_copy( &TB, B ) ); + + lz = mpi_lsb( &TA ); + lzt = mpi_lsb( &TB ); + + if ( lzt < lz ) + lz = lzt; + + MPI_CHK( mpi_shift_r( &TA, lz ) ); + MPI_CHK( mpi_shift_r( &TB, lz ) ); + + TA.s = TB.s = 1; + + while( mpi_cmp_int( &TA, 0 ) != 0 ) + { + MPI_CHK( mpi_shift_r( &TA, mpi_lsb( &TA ) ) ); + MPI_CHK( mpi_shift_r( &TB, mpi_lsb( &TB ) ) ); + + if( mpi_cmp_mpi( &TA, &TB ) >= 0 ) + { + MPI_CHK( mpi_sub_abs( &TA, &TA, &TB ) ); + MPI_CHK( mpi_shift_r( &TA, 1 ) ); + } + else + { + MPI_CHK( mpi_sub_abs( &TB, &TB, &TA ) ); + MPI_CHK( mpi_shift_r( &TB, 1 ) ); + } + } + + MPI_CHK( mpi_shift_l( &TB, lz ) ); + MPI_CHK( mpi_copy( G, &TB ) ); + +cleanup: + + mpi_free( &TB, &TA, &TG, NULL ); + + return( ret ); +} + +#if defined(POLARSSL_GENPRIME) + +/* + * Modular inverse: X = A^-1 mod N (HAC 14.61 / 14.64) + */ +int mpi_inv_mod( mpi *X, mpi *A, mpi *N ) +{ + int ret; + mpi G, TA, TU, U1, U2, TB, TV, V1, V2; + + if( mpi_cmp_int( N, 0 ) <= 0 ) + return( POLARSSL_ERR_MPI_BAD_INPUT_DATA ); + + mpi_init( &TA, &TU, &U1, &U2, &G, + &TB, &TV, &V1, &V2, NULL ); + + MPI_CHK( mpi_gcd( &G, A, N ) ); + + if( mpi_cmp_int( &G, 1 ) != 0 ) + { + ret = POLARSSL_ERR_MPI_NOT_ACCEPTABLE; + goto cleanup; + } + + MPI_CHK( mpi_mod_mpi( &TA, A, N ) ); + MPI_CHK( mpi_copy( &TU, &TA ) ); + MPI_CHK( mpi_copy( &TB, N ) ); + MPI_CHK( mpi_copy( &TV, N ) ); + + MPI_CHK( mpi_lset( &U1, 1 ) ); + MPI_CHK( mpi_lset( &U2, 0 ) ); + MPI_CHK( mpi_lset( &V1, 0 ) ); + MPI_CHK( mpi_lset( &V2, 1 ) ); + + do + { + while( ( TU.p[0] & 1 ) == 0 ) + { + MPI_CHK( mpi_shift_r( &TU, 1 ) ); + + if( ( U1.p[0] & 1 ) != 0 || ( U2.p[0] & 1 ) != 0 ) + { + MPI_CHK( mpi_add_mpi( &U1, &U1, &TB ) ); + MPI_CHK( mpi_sub_mpi( &U2, &U2, &TA ) ); + } + + MPI_CHK( mpi_shift_r( &U1, 1 ) ); + MPI_CHK( mpi_shift_r( &U2, 1 ) ); + } + + while( ( TV.p[0] & 1 ) == 0 ) + { + MPI_CHK( mpi_shift_r( &TV, 1 ) ); + + if( ( V1.p[0] & 1 ) != 0 || ( V2.p[0] & 1 ) != 0 ) + { + MPI_CHK( mpi_add_mpi( &V1, &V1, &TB ) ); + MPI_CHK( mpi_sub_mpi( &V2, &V2, &TA ) ); + } + + MPI_CHK( mpi_shift_r( &V1, 1 ) ); + MPI_CHK( mpi_shift_r( &V2, 1 ) ); + } + + if( mpi_cmp_mpi( &TU, &TV ) >= 0 ) + { + MPI_CHK( mpi_sub_mpi( &TU, &TU, &TV ) ); + MPI_CHK( mpi_sub_mpi( &U1, &U1, &V1 ) ); + MPI_CHK( mpi_sub_mpi( &U2, &U2, &V2 ) ); + } + else + { + MPI_CHK( mpi_sub_mpi( &TV, &TV, &TU ) ); + MPI_CHK( mpi_sub_mpi( &V1, &V1, &U1 ) ); + MPI_CHK( mpi_sub_mpi( &V2, &V2, &U2 ) ); + } + } + while( mpi_cmp_int( &TU, 0 ) != 0 ); + + while( mpi_cmp_int( &V1, 0 ) < 0 ) + MPI_CHK( mpi_add_mpi( &V1, &V1, N ) ); + + while( mpi_cmp_mpi( &V1, N ) >= 0 ) + MPI_CHK( mpi_sub_mpi( &V1, &V1, N ) ); + + MPI_CHK( mpi_copy( X, &V1 ) ); + +cleanup: + + mpi_free( &V2, &V1, &TV, &TB, &G, + &U2, &U1, &TU, &TA, NULL ); + + return( ret ); +} + +static const int small_prime[] = +{ + 3, 5, 7, 11, 13, 17, 19, 23, + 29, 31, 37, 41, 43, 47, 53, 59, + 61, 67, 71, 73, 79, 83, 89, 97, + 101, 103, 107, 109, 113, 127, 131, 137, + 139, 149, 151, 157, 163, 167, 173, 179, + 181, 191, 193, 197, 199, 211, 223, 227, + 229, 233, 239, 241, 251, 257, 263, 269, + 271, 277, 281, 283, 293, 307, 311, 313, + 317, 331, 337, 347, 349, 353, 359, 367, + 373, 379, 383, 389, 397, 401, 409, 419, + 421, 431, 433, 439, 443, 449, 457, 461, + 463, 467, 479, 487, 491, 499, 503, 509, + 521, 523, 541, 547, 557, 563, 569, 571, + 577, 587, 593, 599, 601, 607, 613, 617, + 619, 631, 641, 643, 647, 653, 659, 661, + 673, 677, 683, 691, 701, 709, 719, 727, + 733, 739, 743, 751, 757, 761, 769, 773, + 787, 797, 809, 811, 821, 823, 827, 829, + 839, 853, 857, 859, 863, 877, 881, 883, + 887, 907, 911, 919, 929, 937, 941, 947, + 953, 967, 971, 977, 983, 991, 997, -103 +}; + +/* + * Miller-Rabin primality test (HAC 4.24) + */ +int mpi_is_prime( mpi *X, int (*f_rng)(void *), void *p_rng ) +{ + int ret, i, j, n, s, xs; + mpi W, R, T, A, RR; + unsigned char *p; + + if( mpi_cmp_int( X, 0 ) == 0 ) + return( 0 ); + + mpi_init( &W, &R, &T, &A, &RR, NULL ); + + xs = X->s; X->s = 1; + + /* + * test trivial factors first + */ + if( ( X->p[0] & 1 ) == 0 ) + return( POLARSSL_ERR_MPI_NOT_ACCEPTABLE ); + + for( i = 0; small_prime[i] > 0; i++ ) + { + t_int r; + + if( mpi_cmp_int( X, small_prime[i] ) <= 0 ) + return( 0 ); + + MPI_CHK( mpi_mod_int( &r, X, small_prime[i] ) ); + + if( r == 0 ) + return( POLARSSL_ERR_MPI_NOT_ACCEPTABLE ); + } + + /* + * W = |X| - 1 + * R = W >> lsb( W ) + */ + s = mpi_lsb( &W ); + MPI_CHK( mpi_sub_int( &W, X, 1 ) ); + MPI_CHK( mpi_copy( &R, &W ) ); + MPI_CHK( mpi_shift_r( &R, s ) ); + + i = mpi_msb( X ); + /* + * HAC, table 4.4 + */ + n = ( ( i >= 1300 ) ? 2 : ( i >= 850 ) ? 3 : + ( i >= 650 ) ? 4 : ( i >= 350 ) ? 8 : + ( i >= 250 ) ? 12 : ( i >= 150 ) ? 18 : 27 ); + + for( i = 0; i < n; i++ ) + { + /* + * pick a random A, 1 < A < |X| - 1 + */ + MPI_CHK( mpi_grow( &A, X->n ) ); + + p = (unsigned char *) A.p; + for( j = 0; j < A.n * ciL; j++ ) + *p++ = (unsigned char) f_rng( p_rng ); + + j = mpi_msb( &A ) - mpi_msb( &W ); + MPI_CHK( mpi_shift_r( &A, j + 1 ) ); + A.p[0] |= 3; + + /* + * A = A^R mod |X| + */ + MPI_CHK( mpi_exp_mod( &A, &A, &R, X, &RR ) ); + + if( mpi_cmp_mpi( &A, &W ) == 0 || + mpi_cmp_int( &A, 1 ) == 0 ) + continue; + + j = 1; + while( j < s && mpi_cmp_mpi( &A, &W ) != 0 ) + { + /* + * A = A * A mod |X| + */ + MPI_CHK( mpi_mul_mpi( &T, &A, &A ) ); + MPI_CHK( mpi_mod_mpi( &A, &T, X ) ); + + if( mpi_cmp_int( &A, 1 ) == 0 ) + break; + + j++; + } + + /* + * not prime if A != |X| - 1 or A == 1 + */ + if( mpi_cmp_mpi( &A, &W ) != 0 || + mpi_cmp_int( &A, 1 ) == 0 ) + { + ret = POLARSSL_ERR_MPI_NOT_ACCEPTABLE; + break; + } + } + +cleanup: + + X->s = xs; + + mpi_free( &RR, &A, &T, &R, &W, NULL ); + + return( ret ); +} + +/* + * Prime number generation + */ +int mpi_gen_prime( mpi *X, int nbits, int dh_flag, + int (*f_rng)(void *), void *p_rng ) +{ + int ret, k, n; + unsigned char *p; + mpi Y; + + if( nbits < 3 ) + return( POLARSSL_ERR_MPI_BAD_INPUT_DATA ); + + mpi_init( &Y, NULL ); + + n = BITS_TO_LIMBS( nbits ); + + MPI_CHK( mpi_grow( X, n ) ); + MPI_CHK( mpi_lset( X, 0 ) ); + + p = (unsigned char *) X->p; + for( k = 0; k < X->n * ciL; k++ ) + *p++ = (unsigned char) f_rng( p_rng ); + + k = mpi_msb( X ); + if( k < nbits ) MPI_CHK( mpi_shift_l( X, nbits - k ) ); + if( k > nbits ) MPI_CHK( mpi_shift_r( X, k - nbits ) ); + + X->p[0] |= 3; + + if( dh_flag == 0 ) + { + while( ( ret = mpi_is_prime( X, f_rng, p_rng ) ) != 0 ) + { + if( ret != POLARSSL_ERR_MPI_NOT_ACCEPTABLE ) + goto cleanup; + + MPI_CHK( mpi_add_int( X, X, 2 ) ); + } + } + else + { + MPI_CHK( mpi_sub_int( &Y, X, 1 ) ); + MPI_CHK( mpi_shift_r( &Y, 1 ) ); + + while( 1 ) + { + if( ( ret = mpi_is_prime( X, f_rng, p_rng ) ) == 0 ) + { + if( ( ret = mpi_is_prime( &Y, f_rng, p_rng ) ) == 0 ) + break; + + if( ret != POLARSSL_ERR_MPI_NOT_ACCEPTABLE ) + goto cleanup; + } + + if( ret != POLARSSL_ERR_MPI_NOT_ACCEPTABLE ) + goto cleanup; + + MPI_CHK( mpi_add_int( &Y, X, 1 ) ); + MPI_CHK( mpi_add_int( X, X, 2 ) ); + MPI_CHK( mpi_shift_r( &Y, 1 ) ); + } + } + +cleanup: + + mpi_free( &Y, NULL ); + + return( ret ); +} + +#endif + +#if defined(POLARSSL_SELF_TEST) + +#define GCD_PAIR_COUNT 3 + +static const int gcd_pairs[GCD_PAIR_COUNT][3] = +{ + { 693, 609, 21 }, + { 1764, 868, 28 }, + { 768454923, 542167814, 1 } +}; + +/* + * Checkup routine + */ +int mpi_self_test( int verbose ) +{ + int ret, i; + mpi A, E, N, X, Y, U, V; + + mpi_init( &A, &E, &N, &X, &Y, &U, &V, NULL ); + + MPI_CHK( mpi_read_string( &A, 16, + "EFE021C2645FD1DC586E69184AF4A31E" \ + "D5F53E93B5F123FA41680867BA110131" \ + "944FE7952E2517337780CB0DB80E61AA" \ + "E7C8DDC6C5C6AADEB34EB38A2F40D5E6" ) ); + + MPI_CHK( mpi_read_string( &E, 16, + "B2E7EFD37075B9F03FF989C7C5051C20" \ + "34D2A323810251127E7BF8625A4F49A5" \ + "F3E27F4DA8BD59C47D6DAABA4C8127BD" \ + "5B5C25763222FEFCCFC38B832366C29E" ) ); + + MPI_CHK( mpi_read_string( &N, 16, + "0066A198186C18C10B2F5ED9B522752A" \ + "9830B69916E535C8F047518A889A43A5" \ + "94B6BED27A168D31D4A52F88925AA8F5" ) ); + + MPI_CHK( mpi_mul_mpi( &X, &A, &N ) ); + + MPI_CHK( mpi_read_string( &U, 16, + "602AB7ECA597A3D6B56FF9829A5E8B85" \ + "9E857EA95A03512E2BAE7391688D264A" \ + "A5663B0341DB9CCFD2C4C5F421FEC814" \ + "8001B72E848A38CAE1C65F78E56ABDEF" \ + "E12D3C039B8A02D6BE593F0BBBDA56F1" \ + "ECF677152EF804370C1A305CAF3B5BF1" \ + "30879B56C61DE584A0F53A2447A51E" ) ); + + if( verbose != 0 ) + printf( " MPI test #1 (mul_mpi): " ); + + if( mpi_cmp_mpi( &X, &U ) != 0 ) + { + if( verbose != 0 ) + printf( "failed\n" ); + + return( 1 ); + } + + if( verbose != 0 ) + printf( "passed\n" ); + + MPI_CHK( mpi_div_mpi( &X, &Y, &A, &N ) ); + + MPI_CHK( mpi_read_string( &U, 16, + "256567336059E52CAE22925474705F39A94" ) ); + + MPI_CHK( mpi_read_string( &V, 16, + "6613F26162223DF488E9CD48CC132C7A" \ + "0AC93C701B001B092E4E5B9F73BCD27B" \ + "9EE50D0657C77F374E903CDFA4C642" ) ); + + if( verbose != 0 ) + printf( " MPI test #2 (div_mpi): " ); + + if( mpi_cmp_mpi( &X, &U ) != 0 || + mpi_cmp_mpi( &Y, &V ) != 0 ) + { + if( verbose != 0 ) + printf( "failed\n" ); + + return( 1 ); + } + + if( verbose != 0 ) + printf( "passed\n" ); + + MPI_CHK( mpi_exp_mod( &X, &A, &E, &N, NULL ) ); + + MPI_CHK( mpi_read_string( &U, 16, + "36E139AEA55215609D2816998ED020BB" \ + "BD96C37890F65171D948E9BC7CBAA4D9" \ + "325D24D6A3C12710F10A09FA08AB87" ) ); + + if( verbose != 0 ) + printf( " MPI test #3 (exp_mod): " ); + + if( mpi_cmp_mpi( &X, &U ) != 0 ) + { + if( verbose != 0 ) + printf( "failed\n" ); + + return( 1 ); + } + + if( verbose != 0 ) + printf( "passed\n" ); + + MPI_CHK( mpi_inv_mod( &X, &A, &N ) ); + + MPI_CHK( mpi_read_string( &U, 16, + "003A0AAEDD7E784FC07D8F9EC6E3BFD5" \ + "C3DBA76456363A10869622EAC2DD84EC" \ + "C5B8A74DAC4D09E03B5E0BE779F2DF61" ) ); + + if( verbose != 0 ) + printf( " MPI test #4 (inv_mod): " ); + + if( mpi_cmp_mpi( &X, &U ) != 0 ) + { + if( verbose != 0 ) + printf( "failed\n" ); + + return( 1 ); + } + + if( verbose != 0 ) + printf( "passed\n" ); + + if( verbose != 0 ) + printf( " MPI test #5 (simple gcd): " ); + + for ( i = 0; i < GCD_PAIR_COUNT; i++) + { + MPI_CHK( mpi_lset( &X, gcd_pairs[i][0] ) ); + MPI_CHK( mpi_lset( &Y, gcd_pairs[i][1] ) ); + + MPI_CHK( mpi_gcd( &A, &X, &Y ) ); + + if( mpi_cmp_int( &A, gcd_pairs[i][2] ) != 0 ) + { + if( verbose != 0 ) + printf( "failed at %d\n", i ); + + return( 1 ); + } + } + + if( verbose != 0 ) + printf( "passed\n" ); + +cleanup: + + if( ret != 0 && verbose != 0 ) + printf( "Unexpected error, return code = %08X\n", ret ); + + mpi_free( &V, &U, &Y, &X, &N, &E, &A, NULL ); + + if( verbose != 0 ) + printf( "\n" ); + + return( ret ); +} + +#endif + +#endif |