diff options
Diffstat (limited to 'external/nettle-3.3/nettle/pkcs1.c')
-rw-r--r-- | external/nettle-3.3/nettle/pkcs1.c | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/external/nettle-3.3/nettle/pkcs1.c b/external/nettle-3.3/nettle/pkcs1.c new file mode 100644 index 0000000..87a2d2e --- /dev/null +++ b/external/nettle-3.3/nettle/pkcs1.c @@ -0,0 +1,73 @@ +/* pkcs1.c + + PKCS1 embedding. + + Copyright (C) 2003 Niels Möller + + This file is part of GNU Nettle. + + GNU Nettle is free software: you can redistribute it and/or + modify it under the terms of either: + + * the GNU Lesser General Public License as published by the Free + Software Foundation; either version 3 of the License, or (at your + option) any later version. + + or + + * the GNU General Public License as published by the Free + Software Foundation; either version 3 of the License, or (at your + option) any later version. + + or both in parallel, as here. + + GNU Nettle is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + + You should have received copies of the GNU General Public License and + the GNU Lesser General Public License along with this program. If + not, see http://www.gnu.org/licenses/. +*/ + +#if HAVE_CONFIG_H +# include "config.h" +#endif + +#include <assert.h> +#include <string.h> + +#include "pkcs1.h" + +/* Formats the PKCS#1 padding, of the form + * + * 0x00 0x01 0xff ... 0xff 0x00 id ...digest... + * + * where the 0xff ... 0xff part consists of at least 8 octets. The + * total size equals the octet size of n. + */ +uint8_t * +_pkcs1_signature_prefix(unsigned key_size, + uint8_t *buffer, + unsigned id_size, + const uint8_t *id, + unsigned digest_size) +{ + unsigned j; + + if (key_size < 11 + id_size + digest_size) + return NULL; + + j = key_size - digest_size - id_size; + + memcpy (buffer + j, id, id_size); + buffer[0] = 0; + buffer[1] = 1; + buffer[j-1] = 0; + + assert(j >= 11); + memset(buffer + 2, 0xff, j - 3); + + return buffer + j + id_size; +} |