Import gcrypt public-key cryptography and implement signature checking.
This commit is contained in:
Vladimir 'phcoder' Serbinenko
parent
535714bdcf
commit
5e3b8dcbb5
238 changed files with 40500 additions and 417 deletions
750
grub-core/lib/libgcrypt/mpi/mpicoder.c
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750
grub-core/lib/libgcrypt/mpi/mpicoder.c
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@ -0,0 +1,750 @@
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/* mpicoder.c - Coder for the external representation of MPIs
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* Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003
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* 2008 Free Software Foundation, Inc.
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*
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* This file is part of Libgcrypt.
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*
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* Libgcrypt is free software; you can redistribute it and/or modify
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* it under the terms of the GNU Lesser General Public License as
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* published by the Free Software Foundation; either version 2.1 of
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* the License, or (at your option) any later version.
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*
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* Libgcrypt is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this program; if not, see <http://www.gnu.org/licenses/>.
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*/
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#include <config.h>
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#include <stdio.h>
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#include <string.h>
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#include <stdlib.h>
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#include "mpi-internal.h"
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#include "g10lib.h"
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#define MAX_EXTERN_MPI_BITS 16384
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/* Helper used to scan PGP style MPIs. Returns NULL on failure. */
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static gcry_mpi_t
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mpi_read_from_buffer (const unsigned char *buffer, unsigned *ret_nread,
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int secure)
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{
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int i, j;
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unsigned int nbits, nbytes, nlimbs, nread=0;
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mpi_limb_t a;
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gcry_mpi_t val = MPI_NULL;
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if ( *ret_nread < 2 )
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goto leave;
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nbits = buffer[0] << 8 | buffer[1];
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if ( nbits > MAX_EXTERN_MPI_BITS )
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{
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/* log_debug ("mpi too large (%u bits)\n", nbits); */
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goto leave;
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}
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buffer += 2;
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nread = 2;
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nbytes = (nbits+7) / 8;
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nlimbs = (nbytes+BYTES_PER_MPI_LIMB-1) / BYTES_PER_MPI_LIMB;
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val = secure? mpi_alloc_secure (nlimbs) : mpi_alloc (nlimbs);
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i = BYTES_PER_MPI_LIMB - nbytes % BYTES_PER_MPI_LIMB;
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i %= BYTES_PER_MPI_LIMB;
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j= val->nlimbs = nlimbs;
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val->sign = 0;
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for ( ; j > 0; j-- )
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{
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a = 0;
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for (; i < BYTES_PER_MPI_LIMB; i++ )
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{
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if ( ++nread > *ret_nread )
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{
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/* log_debug ("mpi larger than buffer"); */
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mpi_free (val);
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val = NULL;
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goto leave;
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}
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a <<= 8;
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a |= *buffer++;
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}
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i = 0;
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val->d[j-1] = a;
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}
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leave:
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*ret_nread = nread;
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return val;
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}
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/****************
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* Fill the mpi VAL from the hex string in STR.
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*/
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static int
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mpi_fromstr (gcry_mpi_t val, const char *str)
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{
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int sign = 0;
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int prepend_zero = 0;
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int i, j, c, c1, c2;
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unsigned int nbits, nbytes, nlimbs;
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mpi_limb_t a;
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if ( *str == '-' )
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{
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sign = 1;
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str++;
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}
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/* Skip optional hex prefix. */
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if ( *str == '0' && str[1] == 'x' )
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str += 2;
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nbits = 4 * strlen (str);
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if ((nbits % 8))
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prepend_zero = 1;
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nbytes = (nbits+7) / 8;
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nlimbs = (nbytes+BYTES_PER_MPI_LIMB-1) / BYTES_PER_MPI_LIMB;
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if ( val->alloced < nlimbs )
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mpi_resize (val, nlimbs);
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i = BYTES_PER_MPI_LIMB - (nbytes % BYTES_PER_MPI_LIMB);
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i %= BYTES_PER_MPI_LIMB;
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j = val->nlimbs = nlimbs;
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val->sign = sign;
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for (; j > 0; j--)
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{
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a = 0;
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for (; i < BYTES_PER_MPI_LIMB; i++)
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{
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if (prepend_zero)
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{
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c1 = '0';
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prepend_zero = 0;
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}
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else
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c1 = *str++;
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if (!c1)
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{
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mpi_clear (val);
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return 1; /* Error. */
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}
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c2 = *str++;
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if (!c2)
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{
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mpi_clear (val);
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return 1; /* Error. */
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}
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if ( c1 >= '0' && c1 <= '9' )
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c = c1 - '0';
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else if ( c1 >= 'a' && c1 <= 'f' )
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c = c1 - 'a' + 10;
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else if ( c1 >= 'A' && c1 <= 'F' )
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c = c1 - 'A' + 10;
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else
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{
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mpi_clear (val);
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return 1; /* Error. */
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}
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c <<= 4;
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if ( c2 >= '0' && c2 <= '9' )
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c |= c2 - '0';
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else if( c2 >= 'a' && c2 <= 'f' )
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c |= c2 - 'a' + 10;
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else if( c2 >= 'A' && c2 <= 'F' )
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c |= c2 - 'A' + 10;
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else
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{
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mpi_clear(val);
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return 1; /* Error. */
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}
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a <<= 8;
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a |= c;
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}
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i = 0;
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val->d[j-1] = a;
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}
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return 0; /* Okay. */
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}
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/* Dump the value of A in a format suitable for debugging to
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Libgcrypt's logging stream. Note that one leading space but no
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trailing space or linefeed will be printed. It is okay to pass
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NULL for A. */
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void
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gcry_mpi_dump (const gcry_mpi_t a)
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{
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int i;
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log_printf (" ");
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if (!a)
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log_printf ("[MPI_NULL]");
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else
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{
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if (a->sign)
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log_printf ( "-");
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#if BYTES_PER_MPI_LIMB == 2
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# define X "4"
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#elif BYTES_PER_MPI_LIMB == 4
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# define X "8"
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#elif BYTES_PER_MPI_LIMB == 8
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# define X "16"
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#elif BYTES_PER_MPI_LIMB == 16
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# define X "32"
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#else
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# error please define the format here
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#endif
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for (i=a->nlimbs; i > 0 ; i-- )
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{
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log_printf (i != a->nlimbs? "%0" X "lX":"%lX", (ulong)a->d[i-1]);
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}
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#undef X
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if (!a->nlimbs)
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log_printf ("0");
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}
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}
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/* Convience function used internally. */
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void
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_gcry_log_mpidump (const char *text, gcry_mpi_t a)
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{
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log_printf ("%s:", text);
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gcry_mpi_dump (a);
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log_printf ("\n");
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}
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/* Return an allocated buffer with the MPI (msb first). NBYTES
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receives the length of this buffer. Caller must free the return
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string. This function returns an allocated buffer with NBYTES set
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to zero if the value of A is zero. If sign is not NULL, it will be
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set to the sign of the A. On error NULL is returned and ERRNO set
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appropriately. */
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static unsigned char *
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do_get_buffer (gcry_mpi_t a, unsigned int *nbytes, int *sign, int force_secure)
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{
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unsigned char *p, *buffer;
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mpi_limb_t alimb;
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int i;
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size_t n;
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if (sign)
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*sign = a->sign;
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*nbytes = a->nlimbs * BYTES_PER_MPI_LIMB;
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n = *nbytes? *nbytes:1; /* Allocate at least one byte. */
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p = buffer = (force_secure || mpi_is_secure(a))? gcry_malloc_secure (n)
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: gcry_malloc (n);
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if (!buffer)
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return NULL;
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for (i=a->nlimbs-1; i >= 0; i--)
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{
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alimb = a->d[i];
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#if BYTES_PER_MPI_LIMB == 4
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*p++ = alimb >> 24;
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*p++ = alimb >> 16;
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*p++ = alimb >> 8;
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*p++ = alimb ;
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#elif BYTES_PER_MPI_LIMB == 8
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*p++ = alimb >> 56;
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*p++ = alimb >> 48;
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*p++ = alimb >> 40;
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*p++ = alimb >> 32;
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*p++ = alimb >> 24;
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*p++ = alimb >> 16;
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*p++ = alimb >> 8;
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*p++ = alimb ;
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#else
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# error please implement for this limb size.
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#endif
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}
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/* This is sub-optimal but we need to do the shift operation because
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the caller has to free the returned buffer. */
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for (p=buffer; !*p && *nbytes; p++, --*nbytes)
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;
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if (p != buffer)
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memmove (buffer,p, *nbytes);
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return buffer;
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}
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byte *
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_gcry_mpi_get_buffer (gcry_mpi_t a, unsigned int *nbytes, int *sign)
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{
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return do_get_buffer (a, nbytes, sign, 0);
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}
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byte *
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_gcry_mpi_get_secure_buffer (gcry_mpi_t a, unsigned *nbytes, int *sign)
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{
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return do_get_buffer (a, nbytes, sign, 1);
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}
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/*
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* Use the NBYTES at BUFFER_ARG to update A. Set the sign of a to
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* SIGN.
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*/
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void
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_gcry_mpi_set_buffer (gcry_mpi_t a, const void *buffer_arg,
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unsigned int nbytes, int sign)
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{
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const unsigned char *buffer = (const unsigned char*)buffer_arg;
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const unsigned char *p;
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mpi_limb_t alimb;
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int nlimbs;
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int i;
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nlimbs = (nbytes + BYTES_PER_MPI_LIMB - 1) / BYTES_PER_MPI_LIMB;
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RESIZE_IF_NEEDED(a, nlimbs);
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a->sign = sign;
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for (i=0, p = buffer+nbytes-1; p >= buffer+BYTES_PER_MPI_LIMB; )
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{
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#if BYTES_PER_MPI_LIMB == 4
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alimb = *p-- ;
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alimb |= *p-- << 8 ;
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alimb |= *p-- << 16 ;
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alimb |= *p-- << 24 ;
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#elif BYTES_PER_MPI_LIMB == 8
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alimb = (mpi_limb_t)*p-- ;
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alimb |= (mpi_limb_t)*p-- << 8 ;
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alimb |= (mpi_limb_t)*p-- << 16 ;
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alimb |= (mpi_limb_t)*p-- << 24 ;
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alimb |= (mpi_limb_t)*p-- << 32 ;
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alimb |= (mpi_limb_t)*p-- << 40 ;
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alimb |= (mpi_limb_t)*p-- << 48 ;
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alimb |= (mpi_limb_t)*p-- << 56 ;
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#else
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# error please implement for this limb size.
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#endif
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a->d[i++] = alimb;
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}
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if ( p >= buffer )
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{
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#if BYTES_PER_MPI_LIMB == 4
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alimb = *p--;
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if (p >= buffer)
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alimb |= *p-- << 8;
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if (p >= buffer)
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alimb |= *p-- << 16;
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if (p >= buffer)
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alimb |= *p-- << 24;
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#elif BYTES_PER_MPI_LIMB == 8
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alimb = (mpi_limb_t)*p--;
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if (p >= buffer)
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alimb |= (mpi_limb_t)*p-- << 8;
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if (p >= buffer)
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alimb |= (mpi_limb_t)*p-- << 16;
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if (p >= buffer)
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alimb |= (mpi_limb_t)*p-- << 24;
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if (p >= buffer)
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alimb |= (mpi_limb_t)*p-- << 32;
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if (p >= buffer)
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alimb |= (mpi_limb_t)*p-- << 40;
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if (p >= buffer)
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alimb |= (mpi_limb_t)*p-- << 48;
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if (p >= buffer)
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alimb |= (mpi_limb_t)*p-- << 56;
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#else
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# error please implement for this limb size.
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#endif
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a->d[i++] = alimb;
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}
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a->nlimbs = i;
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gcry_assert (i == nlimbs);
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}
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/* Convert the external representation of an integer stored in BUFFER
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with a length of BUFLEN into a newly create MPI returned in
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RET_MPI. If NBYTES is not NULL, it will receive the number of
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bytes actually scanned after a successful operation. */
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gcry_error_t
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gcry_mpi_scan (struct gcry_mpi **ret_mpi, enum gcry_mpi_format format,
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const void *buffer_arg, size_t buflen, size_t *nscanned)
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{
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const unsigned char *buffer = (const unsigned char*)buffer_arg;
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struct gcry_mpi *a = NULL;
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unsigned int len;
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int secure = (buffer && gcry_is_secure (buffer));
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if (format == GCRYMPI_FMT_SSH)
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len = 0;
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else
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len = buflen;
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if (format == GCRYMPI_FMT_STD)
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{
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const unsigned char *s = buffer;
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a = secure? mpi_alloc_secure ((len+BYTES_PER_MPI_LIMB-1)
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/BYTES_PER_MPI_LIMB)
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: mpi_alloc ((len+BYTES_PER_MPI_LIMB-1)/BYTES_PER_MPI_LIMB);
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if (len)
|
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{
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a->sign = !!(*s & 0x80);
|
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if (a->sign)
|
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{
|
||||
/* FIXME: we have to convert from 2compl to magnitude format */
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mpi_free (a);
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return gcry_error (GPG_ERR_INTERNAL);
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}
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else
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_gcry_mpi_set_buffer (a, s, len, 0);
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}
|
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if (ret_mpi)
|
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{
|
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mpi_normalize ( a );
|
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*ret_mpi = a;
|
||||
}
|
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else
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mpi_free(a);
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return 0;
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}
|
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else if (format == GCRYMPI_FMT_USG)
|
||||
{
|
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a = secure? mpi_alloc_secure ((len+BYTES_PER_MPI_LIMB-1)
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/BYTES_PER_MPI_LIMB)
|
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: mpi_alloc ((len+BYTES_PER_MPI_LIMB-1)/BYTES_PER_MPI_LIMB);
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|
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if (len)
|
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_gcry_mpi_set_buffer (a, buffer, len, 0);
|
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if (ret_mpi)
|
||||
{
|
||||
mpi_normalize ( a );
|
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*ret_mpi = a;
|
||||
}
|
||||
else
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mpi_free(a);
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return 0;
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||||
}
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else if (format == GCRYMPI_FMT_PGP)
|
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{
|
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a = mpi_read_from_buffer (buffer, &len, secure);
|
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if (nscanned)
|
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*nscanned = len;
|
||||
if (ret_mpi && a)
|
||||
{
|
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mpi_normalize (a);
|
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*ret_mpi = a;
|
||||
}
|
||||
else if (a)
|
||||
{
|
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mpi_free(a);
|
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a = NULL;
|
||||
}
|
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return a? 0 : gcry_error (GPG_ERR_INV_OBJ);
|
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}
|
||||
else if (format == GCRYMPI_FMT_SSH)
|
||||
{
|
||||
const unsigned char *s = buffer;
|
||||
size_t n;
|
||||
|
||||
/* This test is not strictly necessary and an assert (!len)
|
||||
would be sufficient. We keep this test in case we later
|
||||
allow the BUFLEN argument to act as a sanitiy check. Same
|
||||
below. */
|
||||
if (len && len < 4)
|
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return gcry_error (GPG_ERR_TOO_SHORT);
|
||||
|
||||
n = (s[0] << 24 | s[1] << 16 | s[2] << 8 | s[3]);
|
||||
s += 4;
|
||||
if (len)
|
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len -= 4;
|
||||
if (len && n > len)
|
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return gcry_error (GPG_ERR_TOO_LARGE);
|
||||
|
||||
a = secure? mpi_alloc_secure ((n+BYTES_PER_MPI_LIMB-1)
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/BYTES_PER_MPI_LIMB)
|
||||
: mpi_alloc ((n+BYTES_PER_MPI_LIMB-1)/BYTES_PER_MPI_LIMB);
|
||||
if (n)
|
||||
{
|
||||
a->sign = !!(*s & 0x80);
|
||||
if (a->sign)
|
||||
{
|
||||
/* FIXME: we have to convert from 2compl to magnitude format */
|
||||
mpi_free(a);
|
||||
return gcry_error (GPG_ERR_INTERNAL);
|
||||
}
|
||||
else
|
||||
_gcry_mpi_set_buffer( a, s, n, 0 );
|
||||
}
|
||||
if (nscanned)
|
||||
*nscanned = n+4;
|
||||
if (ret_mpi)
|
||||
{
|
||||
mpi_normalize ( a );
|
||||
*ret_mpi = a;
|
||||
}
|
||||
else
|
||||
mpi_free(a);
|
||||
return 0;
|
||||
}
|
||||
else if (format == GCRYMPI_FMT_HEX)
|
||||
{
|
||||
/* We can only handle C strings for now. */
|
||||
if (buflen)
|
||||
return gcry_error (GPG_ERR_INV_ARG);
|
||||
|
||||
a = secure? mpi_alloc_secure (0) : mpi_alloc(0);
|
||||
if (mpi_fromstr (a, (const char *)buffer))
|
||||
{
|
||||
mpi_free (a);
|
||||
return gcry_error (GPG_ERR_INV_OBJ);
|
||||
}
|
||||
if (ret_mpi)
|
||||
{
|
||||
mpi_normalize ( a );
|
||||
*ret_mpi = a;
|
||||
}
|
||||
else
|
||||
mpi_free(a);
|
||||
return 0;
|
||||
}
|
||||
else
|
||||
return gcry_error (GPG_ERR_INV_ARG);
|
||||
}
|
||||
|
||||
|
||||
/* Convert the big integer A into the external representation
|
||||
described by FORMAT and store it in the provided BUFFER which has
|
||||
been allocated by the user with a size of BUFLEN bytes. NWRITTEN
|
||||
receives the actual length of the external representation unless it
|
||||
has been passed as NULL. BUFFER may be NULL to query the required
|
||||
length. */
|
||||
gcry_error_t
|
||||
gcry_mpi_print (enum gcry_mpi_format format,
|
||||
unsigned char *buffer, size_t buflen,
|
||||
size_t *nwritten, struct gcry_mpi *a)
|
||||
{
|
||||
unsigned int nbits = mpi_get_nbits (a);
|
||||
size_t len;
|
||||
size_t dummy_nwritten;
|
||||
|
||||
if (!nwritten)
|
||||
nwritten = &dummy_nwritten;
|
||||
|
||||
len = buflen;
|
||||
*nwritten = 0;
|
||||
if (format == GCRYMPI_FMT_STD)
|
||||
{
|
||||
unsigned char *tmp;
|
||||
int extra = 0;
|
||||
unsigned int n;
|
||||
|
||||
if (a->sign)
|
||||
return gcry_error (GPG_ERR_INTERNAL); /* Can't handle it yet. */
|
||||
|
||||
tmp = _gcry_mpi_get_buffer (a, &n, NULL);
|
||||
if (!tmp)
|
||||
return gpg_error_from_syserror ();
|
||||
if (n && (*tmp & 0x80))
|
||||
{
|
||||
n++;
|
||||
extra=1;
|
||||
}
|
||||
|
||||
if (buffer && n > len)
|
||||
{
|
||||
/* The provided buffer is too short. */
|
||||
gcry_free (tmp);
|
||||
return gcry_error (GPG_ERR_TOO_SHORT);
|
||||
}
|
||||
if (buffer)
|
||||
{
|
||||
unsigned char *s = buffer;
|
||||
|
||||
if (extra)
|
||||
*s++ = 0;
|
||||
memcpy (s, tmp, n-extra);
|
||||
}
|
||||
gcry_free(tmp);
|
||||
*nwritten = n;
|
||||
return 0;
|
||||
}
|
||||
else if (format == GCRYMPI_FMT_USG)
|
||||
{
|
||||
unsigned int n = (nbits + 7)/8;
|
||||
|
||||
/* Note: We ignore the sign for this format. */
|
||||
/* FIXME: for performance reasons we should put this into
|
||||
mpi_aprint because we can then use the buffer directly. */
|
||||
if (buffer && n > len)
|
||||
return gcry_error (GPG_ERR_TOO_SHORT);
|
||||
if (buffer)
|
||||
{
|
||||
unsigned char *tmp;
|
||||
|
||||
tmp = _gcry_mpi_get_buffer (a, &n, NULL);
|
||||
if (!tmp)
|
||||
return gpg_error_from_syserror ();
|
||||
memcpy (buffer, tmp, n);
|
||||
gcry_free (tmp);
|
||||
}
|
||||
*nwritten = n;
|
||||
return 0;
|
||||
}
|
||||
else if (format == GCRYMPI_FMT_PGP)
|
||||
{
|
||||
unsigned int n = (nbits + 7)/8;
|
||||
|
||||
/* The PGP format can only handle unsigned integers. */
|
||||
if( a->sign )
|
||||
return gcry_error (GPG_ERR_INV_ARG);
|
||||
|
||||
if (buffer && n+2 > len)
|
||||
return gcry_error (GPG_ERR_TOO_SHORT);
|
||||
|
||||
if (buffer)
|
||||
{
|
||||
unsigned char *tmp;
|
||||
unsigned char *s = buffer;
|
||||
|
||||
s[0] = nbits >> 8;
|
||||
s[1] = nbits;
|
||||
|
||||
tmp = _gcry_mpi_get_buffer (a, &n, NULL);
|
||||
if (!tmp)
|
||||
return gpg_error_from_syserror ();
|
||||
memcpy (s+2, tmp, n);
|
||||
gcry_free (tmp);
|
||||
}
|
||||
*nwritten = n+2;
|
||||
return 0;
|
||||
}
|
||||
else if (format == GCRYMPI_FMT_SSH)
|
||||
{
|
||||
unsigned char *tmp;
|
||||
int extra = 0;
|
||||
unsigned int n;
|
||||
|
||||
if (a->sign)
|
||||
return gcry_error (GPG_ERR_INTERNAL); /* Can't handle it yet. */
|
||||
|
||||
tmp = _gcry_mpi_get_buffer (a, &n, NULL);
|
||||
if (!tmp)
|
||||
return gpg_error_from_syserror ();
|
||||
if (n && (*tmp & 0x80))
|
||||
{
|
||||
n++;
|
||||
extra=1;
|
||||
}
|
||||
|
||||
if (buffer && n+4 > len)
|
||||
{
|
||||
gcry_free(tmp);
|
||||
return gcry_error (GPG_ERR_TOO_SHORT);
|
||||
}
|
||||
|
||||
if (buffer)
|
||||
{
|
||||
unsigned char *s = buffer;
|
||||
|
||||
*s++ = n >> 24;
|
||||
*s++ = n >> 16;
|
||||
*s++ = n >> 8;
|
||||
*s++ = n;
|
||||
if (extra)
|
||||
*s++ = 0;
|
||||
|
||||
memcpy (s, tmp, n-extra);
|
||||
}
|
||||
gcry_free (tmp);
|
||||
*nwritten = 4+n;
|
||||
return 0;
|
||||
}
|
||||
else if (format == GCRYMPI_FMT_HEX)
|
||||
{
|
||||
unsigned char *tmp;
|
||||
int i;
|
||||
int extra = 0;
|
||||
unsigned int n = 0;
|
||||
|
||||
tmp = _gcry_mpi_get_buffer (a, &n, NULL);
|
||||
if (!tmp)
|
||||
return gpg_error_from_syserror ();
|
||||
if (!n || (*tmp & 0x80))
|
||||
extra = 2;
|
||||
|
||||
if (buffer && 2*n + extra + !!a->sign + 1 > len)
|
||||
{
|
||||
gcry_free(tmp);
|
||||
return gcry_error (GPG_ERR_TOO_SHORT);
|
||||
}
|
||||
if (buffer)
|
||||
{
|
||||
unsigned char *s = buffer;
|
||||
|
||||
if (a->sign)
|
||||
*s++ = '-';
|
||||
if (extra)
|
||||
{
|
||||
*s++ = '0';
|
||||
*s++ = '0';
|
||||
}
|
||||
|
||||
for (i=0; i < n; i++)
|
||||
{
|
||||
unsigned int c = tmp[i];
|
||||
|
||||
*s++ = (c >> 4) < 10? '0'+(c>>4) : 'A'+(c>>4)-10 ;
|
||||
c &= 15;
|
||||
*s++ = c < 10? '0'+c : 'A'+c-10 ;
|
||||
}
|
||||
*s++ = 0;
|
||||
*nwritten = s - buffer;
|
||||
}
|
||||
else
|
||||
{
|
||||
*nwritten = 2*n + extra + !!a->sign + 1;
|
||||
}
|
||||
gcry_free (tmp);
|
||||
return 0;
|
||||
}
|
||||
else
|
||||
return gcry_error (GPG_ERR_INV_ARG);
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* Like gcry_mpi_print but this function allocates the buffer itself.
|
||||
* The caller has to supply the address of a pointer. NWRITTEN may be
|
||||
* NULL.
|
||||
*/
|
||||
gcry_error_t
|
||||
gcry_mpi_aprint (enum gcry_mpi_format format,
|
||||
unsigned char **buffer, size_t *nwritten,
|
||||
struct gcry_mpi *a)
|
||||
{
|
||||
size_t n;
|
||||
gcry_error_t rc;
|
||||
|
||||
*buffer = NULL;
|
||||
rc = gcry_mpi_print (format, NULL, 0, &n, a);
|
||||
if (rc)
|
||||
return rc;
|
||||
|
||||
*buffer = mpi_is_secure(a) ? gcry_malloc_secure (n) : gcry_malloc (n);
|
||||
if (!*buffer)
|
||||
return gpg_error_from_syserror ();
|
||||
rc = gcry_mpi_print( format, *buffer, n, &n, a );
|
||||
if (rc)
|
||||
{
|
||||
gcry_free(*buffer);
|
||||
*buffer = NULL;
|
||||
}
|
||||
else if (nwritten)
|
||||
*nwritten = n;
|
||||
return rc;
|
||||
}
|
||||
Loading…
Add table
Add a link
Reference in a new issue