[CRYPTO] sha: Load the SHA[1|256] module by an alias

Loading the crypto algorithm by the alias instead of by module directly
has the advantage that all possible implementations of this algorithm
are loaded automatically and the crypto API can choose the best one
depending on its priority.

Additionally it ensures that the generic implementation as well as the
HW driver (if available) is loaded in case the HW driver needs the
generic version as fallback in corner cases.

Also remove the probe for sha1 in padlock's init code.

Quote from Herbert:
  The probe is actually pointless since we can always probe when
  the algorithm is actually used which does not lead to dead-locks
  like this.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

arch/s390/crypto/sha1_s390.c

@@ -12,7 +12,7 @@
  *   Author(s): Thomas Spatzier
  *		Jan Glauber (jan.glauber@de.ibm.com)
  *
- * Derived from "crypto/sha1.c"
+ * Derived from "crypto/sha1_generic.c"
  *   Copyright (c) Alan Smithee.
  *   Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
  *   Copyright (c) Jean-Francois Dive <jef@linuxbe.org>

arch/s390/crypto/sha256_s390.c

@@ -7,7 +7,7 @@
  *   Copyright IBM Corp. 2005,2007
  *   Author(s): Jan Glauber (jang@de.ibm.com)
  *
- * Derived from "crypto/sha256.c"
+ * Derived from "crypto/sha256_generic.c"
  * and "arch/s390/crypto/sha1_s390.c"
  *
  * This program is free software; you can redistribute it and/or modify it

crypto/Makefile

@@ -21,8 +21,8 @@ obj-$(CONFIG_CRYPTO_XCBC) += xcbc.o
 obj-$(CONFIG_CRYPTO_NULL) += crypto_null.o
 obj-$(CONFIG_CRYPTO_MD4) += md4.o
 obj-$(CONFIG_CRYPTO_MD5) += md5.o
-obj-$(CONFIG_CRYPTO_SHA1) += sha1.o
-obj-$(CONFIG_CRYPTO_SHA256) += sha256.o
+obj-$(CONFIG_CRYPTO_SHA1) += sha1_generic.o
+obj-$(CONFIG_CRYPTO_SHA256) += sha256_generic.o
 obj-$(CONFIG_CRYPTO_SHA512) += sha512.o
 obj-$(CONFIG_CRYPTO_WP512) += wp512.o
 obj-$(CONFIG_CRYPTO_TGR192) += tgr192.o

crypto/sha1.c → crypto/sha1_generic.c

@@ -139,4 +139,4 @@ module_exit(fini);
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm");
 
-MODULE_ALIAS("sha1-generic");
+MODULE_ALIAS("sha1");

crypto/sha256.c → crypto/sha256_generic.c

@@ -339,4 +339,4 @@ module_exit(fini);
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("SHA256 Secure Hash Algorithm");
 
-MODULE_ALIAS("sha256-generic");
+MODULE_ALIAS("sha256");

drivers/crypto/padlock-sha.c

@@ -253,19 +253,6 @@ static struct crypto_alg sha256_alg = {
 	}
 };
 
-static void __init padlock_sha_check_fallbacks(void)
-{
-	if (!crypto_has_hash("sha1", 0, CRYPTO_ALG_ASYNC |
-					CRYPTO_ALG_NEED_FALLBACK))
-		printk(KERN_WARNING PFX
-		       "Couldn't load fallback module for sha1.\n");
-
-	if (!crypto_has_hash("sha256", 0, CRYPTO_ALG_ASYNC |
-					CRYPTO_ALG_NEED_FALLBACK))
-		printk(KERN_WARNING PFX
-		       "Couldn't load fallback module for sha256.\n");
-}
-
 static int __init padlock_init(void)
 {
 	int rc = -ENODEV;
@@ -280,8 +267,6 @@ static int __init padlock_init(void)
 		return -ENODEV;
 	}
 
-	padlock_sha_check_fallbacks();
-
 	rc = crypto_register_alg(&sha1_alg);
 	if (rc)
 		goto out;
@@ -314,5 +299,7 @@ MODULE_DESCRIPTION("VIA PadLock SHA1/SHA256 algorithms support.");
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Michal Ludvig");
 
+MODULE_ALIAS("sha1");
+MODULE_ALIAS("sha256");
 MODULE_ALIAS("sha1-padlock");
 MODULE_ALIAS("sha256-padlock");