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author | Rene Mayrhofer <rene@mayrhofer.eu.org> | 2007-04-12 20:30:08 +0000 |
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committer | Rene Mayrhofer <rene@mayrhofer.eu.org> | 2007-04-12 20:30:08 +0000 |
commit | b0d8ed94fe9e74afb49fdf5f11e4add29879c65c (patch) | |
tree | b20167235628771046e940a82a906a6d0991ee4a /src/libstrongswan/crypto/prf_plus.c | |
parent | ea939d07c84d2a8e51215458063fc05e9c399290 (diff) | |
download | vyos-strongswan-b0d8ed94fe9e74afb49fdf5f11e4add29879c65c.tar.gz vyos-strongswan-b0d8ed94fe9e74afb49fdf5f11e4add29879c65c.zip |
[svn-upgrade] Integrating new upstream version, strongswan (4.1.1)
Diffstat (limited to 'src/libstrongswan/crypto/prf_plus.c')
-rw-r--r-- | src/libstrongswan/crypto/prf_plus.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/src/libstrongswan/crypto/prf_plus.c b/src/libstrongswan/crypto/prf_plus.c new file mode 100644 index 000000000..6bd444b1f --- /dev/null +++ b/src/libstrongswan/crypto/prf_plus.c @@ -0,0 +1,156 @@ +/** + * @file prf_plus.c + * + * @brief Implementation of prf_plus_t. + * + */ + +/* + * Copyright (C) 2005-2006 Martin Willi + * Copyright (C) 2005 Jan Hutter + * Hochschule fuer Technik Rapperswil + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>. + * + * This program 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. + */ + +#include <string.h> + +#include "prf_plus.h" + +typedef struct private_prf_plus_t private_prf_plus_t; + +/** + * Private data of an prf_plus_t object. + * + */ +struct private_prf_plus_t { + /** + * Public interface of prf_plus_t. + */ + prf_plus_t public; + + /** + * PRF to use. + */ + prf_t *prf; + + /** + * Initial seed. + */ + chunk_t seed; + + /** + * Buffer to store current PRF result. + */ + chunk_t buffer; + + /** + * Already given out bytes in current buffer. + */ + size_t given_out; + + /** + * Octet which will be appended to the seed. + */ + u_int8_t appending_octet; +}; + +/** + * Implementation of prf_plus_t.get_bytes. + */ +static void get_bytes(private_prf_plus_t *this, size_t length, u_int8_t *buffer) +{ + chunk_t appending_chunk; + size_t bytes_in_round; + size_t total_bytes_written = 0; + + appending_chunk.ptr = &(this->appending_octet); + appending_chunk.len = 1; + + while (length > 0) + { /* still more to do... */ + if (this->buffer.len == this->given_out) + { /* no bytes left in buffer, get next*/ + this->prf->get_bytes(this->prf, this->buffer, NULL); + this->prf->get_bytes(this->prf, this->seed, NULL); + this->prf->get_bytes(this->prf, appending_chunk, this->buffer.ptr); + this->given_out = 0; + this->appending_octet++; + } + /* how many bytes can we write in this round ? */ + bytes_in_round = min(length, this->buffer.len - this->given_out); + /* copy bytes from buffer with offset */ + memcpy(buffer + total_bytes_written, this->buffer.ptr + this->given_out, bytes_in_round); + + length -= bytes_in_round; + this->given_out += bytes_in_round; + total_bytes_written += bytes_in_round; + } +} + +/** + * Implementation of prf_plus_t.allocate_bytes. + */ +static void allocate_bytes(private_prf_plus_t *this, size_t length, chunk_t *chunk) +{ + chunk->ptr = malloc(length); + chunk->len = length; + this->public.get_bytes(&(this->public), length, chunk->ptr); +} + +/** + * Implementation of prf_plus_t.destroy. + */ +static void destroy(private_prf_plus_t *this) +{ + free(this->buffer.ptr); + free(this->seed.ptr); + free(this); +} + +/* + * Description in header. + */ +prf_plus_t *prf_plus_create(prf_t *prf, chunk_t seed) +{ + private_prf_plus_t *this; + chunk_t appending_chunk; + + this = malloc_thing(private_prf_plus_t); + + /* set public methods */ + this->public.get_bytes = (void (*)(prf_plus_t *,size_t,u_int8_t*))get_bytes; + this->public.allocate_bytes = (void (*)(prf_plus_t *,size_t,chunk_t*))allocate_bytes; + this->public.destroy = (void (*)(prf_plus_t *))destroy; + + /* take over prf */ + this->prf = prf; + + /* allocate buffer for prf output */ + this->buffer.len = prf->get_block_size(prf); + this->buffer.ptr = malloc(this->buffer.len); + + this->appending_octet = 0x01; + + /* clone seed */ + this->seed.ptr = clalloc(seed.ptr, seed.len); + this->seed.len = seed.len; + + /* do the first run */ + appending_chunk.ptr = &(this->appending_octet); + appending_chunk.len = 1; + this->prf->get_bytes(this->prf, this->seed, NULL); + this->prf->get_bytes(this->prf, appending_chunk, this->buffer.ptr); + this->given_out = 0; + this->appending_octet++; + + return &(this->public); +} |