[CRYPTO]: Add encrypt_iv() and decrypt_iv() methods.

crypto/cipher.c

@@ -23,7 +23,8 @@
 #include "internal.h"
 
 typedef void (cryptfn_t)(void *, u8 *, const u8 *);
-typedef void (procfn_t)(struct crypto_tfm *, u8 *, u8*, cryptfn_t, int enc);
+typedef void (procfn_t)(struct crypto_tfm *, u8 *,
+                        u8*, cryptfn_t, int enc, void *);
 
 struct scatter_walk {
 	struct scatterlist	*sg;
@@ -166,7 +167,8 @@ static int copy_chunks(void *buf, struct scatter_walk *walk,
 static int crypt(struct crypto_tfm *tfm,
 		 struct scatterlist *dst,
 		 struct scatterlist *src,
-                 unsigned int nbytes, cryptfn_t crfn, procfn_t prfn, int enc)
+                 unsigned int nbytes, cryptfn_t crfn,
+                 procfn_t prfn, int enc, void *info)
 {
 	struct scatter_walk walk_in, walk_out;
 	const unsigned int bsize = crypto_tfm_alg_blocksize(tfm);
@@ -196,7 +198,7 @@ static int crypt(struct crypto_tfm *tfm,
 
 		copy_chunks(src_p, &walk_in, bsize, 0);
 
-		prfn(tfm, dst_p, src_p, crfn, enc);
+		prfn(tfm, dst_p, src_p, crfn, enc, info);
 
 		scatter_done(&walk_in, 0, nbytes);
 
@@ -211,33 +213,33 @@ static int crypt(struct crypto_tfm *tfm,
 }
 
 static void cbc_process(struct crypto_tfm *tfm,
-                        u8 *dst, u8 *src, cryptfn_t fn, int enc)
+                        u8 *dst, u8 *src, cryptfn_t fn, int enc, void *info)
 {
+	u8 *iv = info;
+	
 	/* Null encryption */
-	if (!tfm->crt_cipher.cit_iv)
+	if (!iv)
 		return;
 		
 	if (enc) {
-		tfm->crt_u.cipher.cit_xor_block(tfm->crt_cipher.cit_iv, src);
-		fn(tfm->crt_ctx, dst, tfm->crt_cipher.cit_iv);
-		memcpy(tfm->crt_cipher.cit_iv, dst,
-		       crypto_tfm_alg_blocksize(tfm));
+		tfm->crt_u.cipher.cit_xor_block(iv, src);
+		fn(tfm->crt_ctx, dst, iv);
+		memcpy(iv, dst, crypto_tfm_alg_blocksize(tfm));
 	} else {
 		const int need_stack = (src == dst);
 		u8 stack[need_stack ? crypto_tfm_alg_blocksize(tfm) : 0];
 		u8 *buf = need_stack ? stack : dst;
 		
 		fn(tfm->crt_ctx, buf, src);
-		tfm->crt_u.cipher.cit_xor_block(buf, tfm->crt_cipher.cit_iv);
-		memcpy(tfm->crt_cipher.cit_iv, src,
-		       crypto_tfm_alg_blocksize(tfm));
+		tfm->crt_u.cipher.cit_xor_block(buf, iv);
+		memcpy(iv, src, crypto_tfm_alg_blocksize(tfm));
 		if (buf != dst)
 			memcpy(dst, buf, crypto_tfm_alg_blocksize(tfm));
 	}
 }
 
 static void ecb_process(struct crypto_tfm *tfm, u8 *dst, u8 *src,
-                        cryptfn_t fn, int enc)
+                        cryptfn_t fn, int enc, void *info)
 {
 	fn(tfm->crt_ctx, dst, src);
 }
@@ -259,7 +261,8 @@ static int ecb_encrypt(struct crypto_tfm *tfm,
                        struct scatterlist *src, unsigned int nbytes)
 {
 	return crypt(tfm, dst, src, nbytes,
-	             tfm->__crt_alg->cra_cipher.cia_encrypt, ecb_process, 1);
+	             tfm->__crt_alg->cra_cipher.cia_encrypt,
+	             ecb_process, 1, NULL);
 }
 
 static int ecb_decrypt(struct crypto_tfm *tfm,
@@ -268,7 +271,8 @@ static int ecb_decrypt(struct crypto_tfm *tfm,
 		       unsigned int nbytes)
 {
 	return crypt(tfm, dst, src, nbytes,
-	             tfm->__crt_alg->cra_cipher.cia_decrypt, ecb_process, 1);
+	             tfm->__crt_alg->cra_cipher.cia_decrypt,
+	             ecb_process, 1, NULL);
 }
 
 static int cbc_encrypt(struct crypto_tfm *tfm,
@@ -277,7 +281,18 @@ static int cbc_encrypt(struct crypto_tfm *tfm,
 		       unsigned int nbytes)
 {
 	return crypt(tfm, dst, src, nbytes,
-	             tfm->__crt_alg->cra_cipher.cia_encrypt, cbc_process, 1);
+	             tfm->__crt_alg->cra_cipher.cia_encrypt,
+	             cbc_process, 1, tfm->crt_cipher.cit_iv);
+}
+
+static int cbc_encrypt_iv(struct crypto_tfm *tfm,
+                          struct scatterlist *dst,
+                          struct scatterlist *src,
+                          unsigned int nbytes, u8 *iv)
+{
+	return crypt(tfm, dst, src, nbytes,
+	             tfm->__crt_alg->cra_cipher.cia_encrypt,
+	             cbc_process, 1, iv);
 }
 
 static int cbc_decrypt(struct crypto_tfm *tfm,
@@ -286,7 +301,18 @@ static int cbc_decrypt(struct crypto_tfm *tfm,
 		       unsigned int nbytes)
 {
 	return crypt(tfm, dst, src, nbytes,
-	             tfm->__crt_alg->cra_cipher.cia_decrypt, cbc_process, 0);
+	             tfm->__crt_alg->cra_cipher.cia_decrypt,
+	             cbc_process, 0, tfm->crt_cipher.cit_iv);
+}
+
+static int cbc_decrypt_iv(struct crypto_tfm *tfm,
+                          struct scatterlist *dst,
+                          struct scatterlist *src,
+                          unsigned int nbytes, u8 *iv)
+{
+	return crypt(tfm, dst, src, nbytes,
+	             tfm->__crt_alg->cra_cipher.cia_decrypt,
+	             cbc_process, 0, iv);
 }
 
 static int nocrypt(struct crypto_tfm *tfm,
@@ -297,6 +323,14 @@ static int nocrypt(struct crypto_tfm *tfm,
 	return -ENOSYS;
 }
 
+static int nocrypt_iv(struct crypto_tfm *tfm,
+                      struct scatterlist *dst,
+                      struct scatterlist *src,
+                      unsigned int nbytes, u8 *iv)
+{
+	return -ENOSYS;
+}
+
 int crypto_init_cipher_flags(struct crypto_tfm *tfm, u32 flags)
 {
 	u32 mode = flags & CRYPTO_TFM_MODE_MASK;
@@ -325,16 +359,22 @@ int crypto_init_cipher_ops(struct crypto_tfm *tfm)
 	case CRYPTO_TFM_MODE_CBC:
 		ops->cit_encrypt = cbc_encrypt;
 		ops->cit_decrypt = cbc_decrypt;
+		ops->cit_encrypt_iv = cbc_encrypt_iv;
+		ops->cit_decrypt_iv = cbc_decrypt_iv;
 		break;
 		
 	case CRYPTO_TFM_MODE_CFB:
 		ops->cit_encrypt = nocrypt;
 		ops->cit_decrypt = nocrypt;
+		ops->cit_encrypt_iv = nocrypt_iv;
+		ops->cit_decrypt_iv = nocrypt_iv;
 		break;
 	
 	case CRYPTO_TFM_MODE_CTR:
 		ops->cit_encrypt = nocrypt;
 		ops->cit_decrypt = nocrypt;
+		ops->cit_encrypt_iv = nocrypt_iv;
+		ops->cit_decrypt_iv = nocrypt_iv;
 		break;
 
 	default:

include/linux/crypto.h

@@ -134,10 +134,18 @@ struct cipher_tfm {
 			   struct scatterlist *dst,
 			   struct scatterlist *src,
 			   unsigned int nbytes);
+	int (*cit_encrypt_iv)(struct crypto_tfm *tfm,
+	                      struct scatterlist *dst,
+	                      struct scatterlist *src,
+	                      unsigned int nbytes, u8 *iv);
 	int (*cit_decrypt)(struct crypto_tfm *tfm,
 			   struct scatterlist *dst,
 			   struct scatterlist *src,
 			   unsigned int nbytes);
+	int (*cit_decrypt_iv)(struct crypto_tfm *tfm,
+			   struct scatterlist *dst,
+			   struct scatterlist *src,
+			   unsigned int nbytes, u8 *iv);
 	void (*cit_xor_block)(u8 *dst, const u8 *src);
 };
 
@@ -286,6 +294,16 @@ static inline int crypto_cipher_encrypt(struct crypto_tfm *tfm,
 	return tfm->crt_cipher.cit_encrypt(tfm, dst, src, nbytes);
 }                                        
 
+static inline int crypto_cipher_encrypt_iv(struct crypto_tfm *tfm,
+                                           struct scatterlist *dst,
+                                           struct scatterlist *src,
+                                           unsigned int nbytes, u8 *iv)
+{
+	BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
+	BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
+	return tfm->crt_cipher.cit_encrypt_iv(tfm, dst, src, nbytes, iv);
+}                                        
+
 static inline int crypto_cipher_decrypt(struct crypto_tfm *tfm,
                                         struct scatterlist *dst,
                                         struct scatterlist *src,
@@ -295,6 +313,16 @@ static inline int crypto_cipher_decrypt(struct crypto_tfm *tfm,
 	return tfm->crt_cipher.cit_decrypt(tfm, dst, src, nbytes);
 }
 
+static inline int crypto_cipher_decrypt_iv(struct crypto_tfm *tfm,
+                                           struct scatterlist *dst,
+                                           struct scatterlist *src,
+                                           unsigned int nbytes, u8 *iv)
+{
+	BUG_ON(crypto_tfm_alg_type(tfm) != CRYPTO_ALG_TYPE_CIPHER);
+	BUG_ON(tfm->crt_cipher.cit_mode == CRYPTO_TFM_MODE_ECB);
+	return tfm->crt_cipher.cit_decrypt_iv(tfm, dst, src, nbytes, iv);
+}
+
 static inline void crypto_cipher_set_iv(struct crypto_tfm *tfm,
                                         const u8 *src, unsigned int len)
 {