summaryrefslogtreecommitdiffstats
path: root/qemu/roms/ipxe/src/crypto/hmac.c
diff options
context:
space:
mode:
authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/ipxe/src/crypto/hmac.c
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (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.c123
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 );
+}