[CRYPTO]: Add null algorithms and minor cleanups.

Documentation/crypto/api-intro.txt

@@ -73,6 +73,13 @@ add the following line to /etc/modules.conf:
 
   alias des3_ede des
 
+The Null algorithms reside in the crypto_null module, so these lines
+should also be added:
+
+  alias cipher_null crypto_null
+  alias digest_null crypto_null
+  alias compress_null crypto_null
+
 
 DEVELOPER NOTES
 

crypto/Kconfig

@@ -16,6 +16,12 @@ config CRYPTO_HMAC
 	  HMAC: Keyed-Hashing for Message Authentication (RFC2104).
 	  This is required for IPSec.
 
+config CRYPTO_NULL
+	tristate "Null algorithms"
+	depends on CRYPTO
+	help
+	  These are 'Null' algorithms, used by IPsec, which do nothing.
+
 config CRYPTO_MD4
 	tristate "MD4 digest algorithm"
 	depends on CRYPTO

crypto/Makefile

@@ -9,6 +9,7 @@ autoload-crypto-$(CONFIG_KMOD) = autoload.o
 obj-$(CONFIG_CRYPTO) += api.o cipher.o digest.o compress.o $(autoload-crypto-y)
 
 obj-$(CONFIG_CRYPTO_HMAC) += hmac.o
+obj-$(CONFIG_CRYPTO_NULL) += crypto_null.o
 obj-$(CONFIG_CRYPTO_MD4) += md4.o
 obj-$(CONFIG_CRYPTO_MD5) += md5.o
 obj-$(CONFIG_CRYPTO_SHA1) += sha1.o

crypto/api.c

@@ -63,7 +63,7 @@ static int crypto_init_flags(struct crypto_tfm *tfm, u32 flags)
 	case CRYPTO_ALG_TYPE_DIGEST:
 		return crypto_init_digest_flags(tfm, flags);
 		
-	case CRYPTO_ALG_TYPE_COMP:
+	case CRYPTO_ALG_TYPE_COMPRESS:
 		return crypto_init_compress_flags(tfm, flags);
 	
 	default:
@@ -83,7 +83,7 @@ static int crypto_init_ops(struct crypto_tfm *tfm)
 	case CRYPTO_ALG_TYPE_DIGEST:
 		return crypto_init_digest_ops(tfm);
 		
-	case CRYPTO_ALG_TYPE_COMP:
+	case CRYPTO_ALG_TYPE_COMPRESS:
 		return crypto_init_compress_ops(tfm);
 	
 	default:

crypto/compress.c

@@ -18,15 +18,15 @@
 #include <linux/string.h>
 #include "internal.h"
 
-/*
- * This code currently implements blazingly fast and
- * lossless Quadruple ROT13 compression.
- */
 static void crypto_compress(struct crypto_tfm *tfm)
-{ }
+{
+	tfm->__crt_alg->cra_compress.coa_compress();
+}
 
 static void crypto_decompress(struct crypto_tfm *tfm)
-{ }
+{
+	tfm->__crt_alg->cra_compress.coa_decompress();
+}
 
 int crypto_init_compress_flags(struct crypto_tfm *tfm, u32 flags)
 {

include/linux/crypto.h

@@ -29,7 +29,7 @@
 #define CRYPTO_ALG_TYPE_MASK		0x000000ff
 #define CRYPTO_ALG_TYPE_CIPHER		0x00000001
 #define CRYPTO_ALG_TYPE_DIGEST		0x00000002
-#define CRYPTO_ALG_TYPE_COMP		0x00000004
+#define CRYPTO_ALG_TYPE_COMPRESS	0x00000004
 
 
 /*
@@ -209,16 +209,19 @@ static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
 
 static inline unsigned int crypto_tfm_alg_min_keysize(struct crypto_tfm *tfm)
 {
+	BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 	return tfm->__crt_alg->cra_cipher.cia_min_keysize;
 }
 
 static inline unsigned int crypto_tfm_alg_max_keysize(struct crypto_tfm *tfm)
 {
+	BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 	return tfm->__crt_alg->cra_cipher.cia_max_keysize;
 }
 
 static inline unsigned int crypto_tfm_alg_ivsize(struct crypto_tfm *tfm)
 {
+	BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
 	return tfm->__crt_alg->cra_cipher.cia_ivsize;
 }
 
@@ -229,6 +232,7 @@ static inline unsigned int crypto_tfm_alg_blocksize(struct crypto_tfm *tfm)
 
 static inline unsigned int crypto_tfm_alg_digestsize(struct crypto_tfm *tfm)
 {
+	BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_DIGEST);
 	return tfm->__crt_alg->cra_digest.dia_digestsize;
 }
 
@@ -302,13 +306,13 @@ static inline void crypto_cipher_get_iv(struct crypto_tfm *tfm,
 
 static inline void crypto_comp_compress(struct crypto_tfm *tfm)
 {
-	BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMP);
+	BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 	tfm->crt_compress.cot_compress(tfm);
 }
 
 static inline void crypto_comp_decompress(struct crypto_tfm *tfm) 
 {
-	BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMP);
+	BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_COMPRESS);
 	tfm->crt_compress.cot_decompress(tfm);
 }