Added generic CHAP layer, independent of iSCSI

src/crypto/chap.c

@@ -0,0 +1,108 @@
+/*
+ * Copyright (C) 2006 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <assert.h>
+#include <malloc.h>
+#include <gpxe/crypto.h>
+#include <gpxe/chap.h>
+
+/** @file
+ *
+ * CHAP protocol
+ *
+ */
+
+/**
+ * Initialise CHAP challenge/response
+ *
+ * @v chap		CHAP challenge/response
+ * @v digest		Digest algorithm to use
+ * @ret rc		Return status code
+ *
+ * Initialises a CHAP challenge/response structure.  This routine
+ * allocates memory, and so may fail.  The allocated memory must
+ * eventually be freed by a call to chap_finish().
+ */
+int chap_init ( struct chap_challenge *chap,
+		struct digest_algorithm *digest ) {
+	assert ( chap->digest == NULL );
+	assert ( chap->digest_context == NULL );
+	assert ( chap->response == NULL );
+
+	chap->digest = digest;
+	chap->digest_context = malloc ( digest->context_len );
+	if ( ! chap->digest_context )
+		goto err;
+	chap->response = malloc ( digest->digest_len );
+	if ( ! chap->response )
+		goto err;
+	chap->response_len = digest->digest_len;
+	chap->digest->init ( chap->digest_context );
+	return 0;
+
+ err:
+	chap_finish ( chap );
+	return -ENOMEM;
+}
+
+/**
+ * Add data to the CHAP challenge
+ *
+ * @v chap		CHAP challenge/response
+ * @v data		Data to add
+ * @v len		Length of data to add
+ */
+void chap_update ( struct chap_challenge *chap, const void *data,
+		   size_t len ) {
+	assert ( chap->digest != NULL );
+	assert ( chap->digest_context != NULL );
+
+	chap->digest->update ( chap->digest_context, data, len );
+}
+
+/**
+ * Respond to the CHAP challenge
+ *
+ * @v chap		CHAP challenge/response
+ *
+ * Calculates the final CHAP response value, and places it in @c
+ * chap->response, with a length of @c chap->response_len.
+ */
+void chap_respond ( struct chap_challenge *chap ) {
+	assert ( chap->digest != NULL );
+	assert ( chap->digest_context != NULL );
+	assert ( chap->response != NULL );
+
+	chap->digest->finish ( chap->digest_context, chap->response );
+}
+
+/**
+ * Free resources used by a CHAP challenge/response
+ *
+ * @v chap		CHAP challenge/response
+ */
+void chap_finish ( struct chap_challenge *chap ) {
+	free ( chap->digest_context );
+	chap->digest_context = NULL;
+	free ( chap->response );
+	chap->response = NULL;
+	chap->digest = NULL;
+}

src/crypto/md5.c

@@ -26,6 +26,16 @@
 #include <gpxe/crypto.h>
 #include <gpxe/md5.h>
 
+#define MD5_DIGEST_SIZE		16
+#define MD5_BLOCK_WORDS		16
+#define MD5_HASH_WORDS		4
+
+struct md5_ctx {
+	u32 hash[MD5_HASH_WORDS];
+	u32 block[MD5_BLOCK_WORDS];
+	u64 byte_count;
+};
+
 #define __md5step __attribute__ (( regparm ( 3 ) ))
 
 struct md5_step {
@@ -150,15 +160,16 @@ static inline void cpu_to_le32_array(u32 *buf, unsigned int words)
 	}
 }
 
-static inline void md5_transform_helper(struct md5_context *ctx)
+static inline void md5_transform_helper(struct md5_ctx *ctx)
 {
 	le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(u32));
 	md5_transform(ctx->hash, ctx->block);
 }
 
-void md5_init ( struct md5_context *context )
+static void md5_init(void *context)
 {
-	struct md5_context *mctx = context;
+	struct md5_ctx *mctx = context;
+
 	mctx->hash[0] = 0x67452301;
 	mctx->hash[1] = 0xefcdab89;
 	mctx->hash[2] = 0x98badcfe;
@@ -166,9 +177,9 @@ void md5_init ( struct md5_context *context )
 	mctx->byte_count = 0;
 }
 
-void md5_update ( struct md5_context *context, const void *data, size_t len )
+static void md5_update(void *context, const void *data, size_t len)
 {
-	struct md5_context *mctx = context;
+	struct md5_ctx *mctx = context;
 	const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f);
 
 	mctx->byte_count += len;
@@ -196,9 +207,9 @@ void md5_update ( struct md5_context *context, const void *data, size_t len )
 	memcpy(mctx->block, data, len);
 }
 
-void md5_finish ( struct md5_context *context, struct md5_hash *out )
+static void md5_finish(void *context, void *out)
 {
-	struct md5_context *mctx = context;
+	struct md5_ctx *mctx = context;
 	const unsigned int offset = mctx->byte_count & 0x3f;
 	char *p = (char *)mctx->block + offset;
 	int padding = 56 - (offset + 1);
@@ -222,12 +233,10 @@ void md5_finish ( struct md5_context *context, struct md5_hash *out )
 	memset(mctx, 0, sizeof(*mctx));
 }
 
-/*
 struct digest_algorithm md5_algorithm = {
-	.context_len	= sizeof ( struct md5_context ),
+	.context_len	= sizeof ( struct md5_ctx ),
 	.digest_len	= MD5_DIGEST_SIZE,
 	.init		= md5_init,
 	.update		= md5_update,
 	.finish		= md5_finish,
 };
-*/

src/include/gpxe/chap.h

@@ -0,0 +1,51 @@
+#ifndef _GPXE_CHAP_H
+#define _GPXE_CHAP_H
+
+/** @file
+ *
+ * CHAP protocol
+ *
+ */
+
+#include <stdint.h>
+#include <gpxe/md5.h>
+
+struct digest_algorithm;
+
+/** A CHAP challenge/response */
+struct chap_challenge {
+	/** Digest algorithm used for the response */
+	struct digest_algorithm *digest;
+	/** Context used by the digest algorithm */
+	uint8_t *digest_context;
+	/** CHAP response */
+	uint8_t *response;
+	/** Length of CHAP response */
+	size_t response_len;
+};
+
+extern int chap_init ( struct chap_challenge *chap,
+		       struct digest_algorithm *digest );
+extern void chap_update ( struct chap_challenge *chap, const void *data,
+			  size_t len );
+extern void chap_respond ( struct chap_challenge *chap );
+extern void chap_finish ( struct chap_challenge *chap );
+
+/**
+ * Add identifier data to the CHAP challenge
+ *
+ * @v chap		CHAP challenge/response
+ * @v identifier	CHAP identifier
+ *
+ * The CHAP identifier is the first byte of the CHAP challenge.  This
+ * function is a notational convenience for calling chap_update() for
+ * the identifier byte.
+ */
+static inline void chap_set_identifier ( struct chap_challenge *chap,
+					 unsigned int identifier ) {
+	uint8_t ident_byte = identifier;
+
+	chap_update ( chap, &ident_byte, sizeof ( ident_byte ) );
+}
+
+#endif /* _GPXE_CHAP_H */

src/include/gpxe/md5.h

@@ -1,25 +1,8 @@
 #ifndef _GPXE_MD5_H
 #define _GPXE_MD5_H
 
-#include <stdint.h>
+struct digest_algorithm;
 
-#define MD5_DIGEST_SIZE		16
-#define MD5_BLOCK_WORDS		16
-#define MD5_HASH_WORDS		4
-
-struct md5_context {
-	u32 hash[MD5_HASH_WORDS];
-	u32 block[MD5_BLOCK_WORDS];
-	u64 byte_count;
-};
-
-struct md5_hash {
-	u8 hash[MD5_DIGEST_SIZE];
-};
-
-extern void md5_init ( struct md5_context *context );
-extern void md5_update ( struct md5_context *context, const void *data,
-			 size_t len );
-extern void md5_finish ( struct md5_context *context, struct md5_hash *hash );
+extern struct digest_algorithm md5_algorithm;
 
 #endif /* _GPXE_MD5_H */