diff options
Diffstat (limited to 'grub-core/lib/libgcrypt/mpi/mpi-inline.h')
| -rw-r--r-- | grub-core/lib/libgcrypt/mpi/mpi-inline.h | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/grub-core/lib/libgcrypt/mpi/mpi-inline.h b/grub-core/lib/libgcrypt/mpi/mpi-inline.h new file mode 100644 index 0000000..94e2aec --- /dev/null +++ b/grub-core/lib/libgcrypt/mpi/mpi-inline.h @@ -0,0 +1,161 @@ +/* mpi-inline.h - Internal to the Multi Precision Integers + * Copyright (C) 1994, 1996, 1998, 1999, + * 2001, 2002 Free Software Foundation, Inc. + * + * This file is part of Libgcrypt. + * + * Libgcrypt is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as + * published by the Free Software Foundation; either version 2.1 of + * the License, or (at your option) any later version. + * + * Libgcrypt is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser 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 + * + * Note: This code is heavily based on the GNU MP Library. + * Actually it's the same code with only minor changes in the + * way the data is stored; this is to support the abstraction + * of an optional secure memory allocation which may be used + * to avoid revealing of sensitive data due to paging etc. + */ + +#ifndef G10_MPI_INLINE_H +#define G10_MPI_INLINE_H + +/* Starting with gcc 4.3 "extern inline" conforms in c99 mode to the + c99 semantics. To keep the useful old semantics we use an + attribute. */ +#ifndef G10_MPI_INLINE_DECL +# ifdef __GNUC_STDC_INLINE__ +# define G10_MPI_INLINE_DECL extern inline __attribute__ ((__gnu_inline__)) +# else +# define G10_MPI_INLINE_DECL extern __inline__ +# endif +#endif + +G10_MPI_INLINE_DECL mpi_limb_t +_gcry_mpih_add_1( mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, + mpi_size_t s1_size, mpi_limb_t s2_limb) +{ + mpi_limb_t x; + + x = *s1_ptr++; + s2_limb += x; + *res_ptr++ = s2_limb; + if( s2_limb < x ) { /* sum is less than the left operand: handle carry */ + while( --s1_size ) { + x = *s1_ptr++ + 1; /* add carry */ + *res_ptr++ = x; /* and store */ + if( x ) /* not 0 (no overflow): we can stop */ + goto leave; + } + return 1; /* return carry (size of s1 to small) */ + } + + leave: + if( res_ptr != s1_ptr ) { /* not the same variable */ + mpi_size_t i; /* copy the rest */ + for( i=0; i < s1_size-1; i++ ) + res_ptr[i] = s1_ptr[i]; + } + return 0; /* no carry */ +} + + + +G10_MPI_INLINE_DECL mpi_limb_t +_gcry_mpih_add(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, mpi_size_t s1_size, + mpi_ptr_t s2_ptr, mpi_size_t s2_size) +{ + mpi_limb_t cy = 0; + + if( s2_size ) + cy = _gcry_mpih_add_n( res_ptr, s1_ptr, s2_ptr, s2_size ); + + if( s1_size - s2_size ) + cy = _gcry_mpih_add_1( res_ptr + s2_size, s1_ptr + s2_size, + s1_size - s2_size, cy); + return cy; +} + + +G10_MPI_INLINE_DECL mpi_limb_t +_gcry_mpih_sub_1(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, + mpi_size_t s1_size, mpi_limb_t s2_limb ) +{ + mpi_limb_t x; + + x = *s1_ptr++; + s2_limb = x - s2_limb; + *res_ptr++ = s2_limb; + if( s2_limb > x ) { + while( --s1_size ) { + x = *s1_ptr++; + *res_ptr++ = x - 1; + if( x ) + goto leave; + } + return 1; + } + + leave: + if( res_ptr != s1_ptr ) { + mpi_size_t i; + for( i=0; i < s1_size-1; i++ ) + res_ptr[i] = s1_ptr[i]; + } + return 0; +} + + + +G10_MPI_INLINE_DECL mpi_limb_t +_gcry_mpih_sub( mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr, mpi_size_t s1_size, + mpi_ptr_t s2_ptr, mpi_size_t s2_size) +{ + mpi_limb_t cy = 0; + + if( s2_size ) + cy = _gcry_mpih_sub_n(res_ptr, s1_ptr, s2_ptr, s2_size); + + if( s1_size - s2_size ) + cy = _gcry_mpih_sub_1(res_ptr + s2_size, s1_ptr + s2_size, + s1_size - s2_size, cy); + return cy; +} + +/**************** + * Compare OP1_PTR/OP1_SIZE with OP2_PTR/OP2_SIZE. + * There are no restrictions on the relative sizes of + * the two arguments. + * Return 1 if OP1 > OP2, 0 if they are equal, and -1 if OP1 < OP2. + */ +G10_MPI_INLINE_DECL int +_gcry_mpih_cmp( mpi_ptr_t op1_ptr, mpi_ptr_t op2_ptr, mpi_size_t size ) +{ + mpi_size_t i; + mpi_limb_t op1_word, op2_word; + + for( i = size - 1; i >= 0 ; i--) { + op1_word = op1_ptr[i]; + op2_word = op2_ptr[i]; + if( op1_word != op2_word ) + goto diff; + } + return 0; + + diff: + /* This can *not* be simplified to + * op2_word - op2_word + * since that expression might give signed overflow. */ + return (op1_word > op2_word) ? 1 : -1; +} + + +#endif /*G10_MPI_INLINE_H*/ |