diff options
author | Yang Zhang <yang.z.zhang@intel.com> | 2015-08-28 09:58:54 +0800 |
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committer | Yang Zhang <yang.z.zhang@intel.com> | 2015-09-01 12:44:00 +0800 |
commit | e44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch) | |
tree | 66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/ipxe/src/crypto/hmac.c | |
parent | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff) |
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5
Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/ipxe/src/crypto/hmac.c')
-rw-r--r-- | qemu/roms/ipxe/src/crypto/hmac.c | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/qemu/roms/ipxe/src/crypto/hmac.c b/qemu/roms/ipxe/src/crypto/hmac.c new file mode 100644 index 000000000..e9459198c --- /dev/null +++ b/qemu/roms/ipxe/src/crypto/hmac.c @@ -0,0 +1,123 @@ +/* + * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>. + * + * 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 any later version. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + */ + +FILE_LICENCE ( GPL2_OR_LATER ); + +/** + * @file + * + * Keyed-Hashing for Message Authentication + */ + +#include <string.h> +#include <assert.h> +#include <ipxe/crypto.h> +#include <ipxe/hmac.h> + +/** + * Reduce HMAC key length + * + * @v digest Digest algorithm to use + * @v digest_ctx Digest context + * @v key Key + * @v key_len Length of key + */ +static void hmac_reduce_key ( struct digest_algorithm *digest, + void *key, size_t *key_len ) { + uint8_t digest_ctx[digest->ctxsize]; + + digest_init ( digest, digest_ctx ); + digest_update ( digest, digest_ctx, key, *key_len ); + digest_final ( digest, digest_ctx, key ); + *key_len = digest->digestsize; +} + +/** + * Initialise HMAC + * + * @v digest Digest algorithm to use + * @v digest_ctx Digest context + * @v key Key + * @v key_len Length of key + * + * The length of the key should be less than the block size of the + * digest algorithm being used. (If the key length is greater, it + * will be replaced with its own digest, and key_len will be updated + * accordingly). + */ +void hmac_init ( struct digest_algorithm *digest, void *digest_ctx, + void *key, size_t *key_len ) { + unsigned char k_ipad[digest->blocksize]; + unsigned int i; + + /* Reduce key if necessary */ + if ( *key_len > sizeof ( k_ipad ) ) + hmac_reduce_key ( digest, key, key_len ); + + /* Construct input pad */ + memset ( k_ipad, 0, sizeof ( k_ipad ) ); + memcpy ( k_ipad, key, *key_len ); + for ( i = 0 ; i < sizeof ( k_ipad ) ; i++ ) { + k_ipad[i] ^= 0x36; + } + + /* Start inner hash */ + digest_init ( digest, digest_ctx ); + digest_update ( digest, digest_ctx, k_ipad, sizeof ( k_ipad ) ); +} + +/** + * Finalise HMAC + * + * @v digest Digest algorithm to use + * @v digest_ctx Digest context + * @v key Key + * @v key_len Length of key + * @v hmac HMAC digest to fill in + * + * The length of the key should be less than the block size of the + * digest algorithm being used. (If the key length is greater, it + * will be replaced with its own digest, and key_len will be updated + * accordingly). + */ +void hmac_final ( struct digest_algorithm *digest, void *digest_ctx, + void *key, size_t *key_len, void *hmac ) { + unsigned char k_opad[digest->blocksize]; + unsigned int i; + + /* Reduce key if necessary */ + if ( *key_len > sizeof ( k_opad ) ) + hmac_reduce_key ( digest, key, key_len ); + + /* Construct output pad */ + memset ( k_opad, 0, sizeof ( k_opad ) ); + memcpy ( k_opad, key, *key_len ); + for ( i = 0 ; i < sizeof ( k_opad ) ; i++ ) { + k_opad[i] ^= 0x5c; + } + + /* Finish inner hash */ + digest_final ( digest, digest_ctx, hmac ); + + /* Perform outer hash */ + digest_init ( digest, digest_ctx ); + digest_update ( digest, digest_ctx, k_opad, sizeof ( k_opad ) ); + digest_update ( digest, digest_ctx, hmac, digest->digestsize ); + digest_final ( digest, digest_ctx, hmac ); +} |