Add qemu 2.4.0

[kvmfornfv.git] / qemu / roms / ipxe / src / crypto / hmac.c

diff --git a/qemu/roms/ipxe/src/crypto/hmac.c b/qemu/roms/ipxe/src/crypto/hmac.c
new file mode 100644 (file)
index 0000000..e945919
--- /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 );
+}