[CRYPTO] padlock: Helper module padlock.ko

Compile a helper module padlock.ko that will try
to autoload all configured padlock algorithms.

This also provides backward compatibility with 
the ancient times before padlock.ko was renamed 
to padlock-aes.ko

Signed-off-by: Michal Ludvig <michal@logix.cz>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/Kconfig

@@ -1,19 +1,28 @@
 menu "Hardware crypto devices"
 
 config CRYPTO_DEV_PADLOCK
-	bool "Support for VIA PadLock ACE"
+	tristate "Support for VIA PadLock ACE"
 	depends on X86_32
 	select CRYPTO_ALGAPI
-	default y
+	default m
 	help
 	  Some VIA processors come with an integrated crypto engine
 	  (so called VIA PadLock ACE, Advanced Cryptography Engine)
 	  that provides instructions for very fast cryptographic
 	  operations with supported algorithms.
 
 	  The instructions are used only when the CPU supports them.
-	  Otherwise software encryption is used. If you are unsure,
-	  say Y.
+	  Otherwise software encryption is used.
+
+	  Selecting M for this option will compile a helper module
+	  padlock.ko that should autoload all below configured
+	  algorithms. Don't worry if your hardware does not support
+	  some or all of them. In such case padlock.ko will
+	  simply write a single line into the kernel log informing
+	  about its failure but everything will keep working fine.
+
+	  If you are unsure, say M. The compiled module will be
+	  called padlock.ko
 
 config CRYPTO_DEV_PADLOCK_AES
 	tristate "PadLock driver for AES algorithm"

drivers/crypto/Makefile

@@ -1,2 +1,3 @@
+obj-$(CONFIG_CRYPTO_DEV_PADLOCK) += padlock.o
 obj-$(CONFIG_CRYPTO_DEV_PADLOCK_AES) += padlock-aes.o
 obj-$(CONFIG_CRYPTO_DEV_PADLOCK_SHA) += padlock-sha.o

drivers/crypto/padlock-aes.c

@@ -544,6 +544,3 @@ MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Michal Ludvig");
 
 MODULE_ALIAS("aes-padlock");
-
-/* This module used to be called padlock. */
-MODULE_ALIAS("padlock");

drivers/crypto/padlock.c

@@ -0,0 +1,58 @@
+/*
+ * Cryptographic API.
+ *
+ * Support for VIA PadLock hardware crypto engine.
+ *
+ * Copyright (c) 2006  Michal Ludvig <michal@logix.cz>
+ *
+ * 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.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/crypto.h>
+#include <linux/cryptohash.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/scatterlist.h>
+#include "padlock.h"
+
+static int __init padlock_init(void)
+{
+	int success = 0;
+
+	if (crypto_alg_available("aes-padlock", 0))
+		success++;
+
+	if (crypto_alg_available("sha1-padlock", 0))
+		success++;
+
+	if (crypto_alg_available("sha256-padlock", 0))
+		success++;
+
+	if (!success) {
+		printk(KERN_WARNING PFX "No VIA PadLock drivers have been loaded.\n");
+		return -ENODEV;
+	}
+
+	printk(KERN_NOTICE PFX "%d drivers are available.\n", success);
+
+	return 0;
+}
+
+static void __exit padlock_fini(void)
+{
+}
+
+module_init(padlock_init);
+module_exit(padlock_fini);
+
+MODULE_DESCRIPTION("Load all configured PadLock algorithms.");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Michal Ludvig");
+