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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /crypto/cipher.c
Initial import
Diffstat (limited to 'crypto/cipher.c')
-rw-r--r--crypto/cipher.c122
1 files changed, 122 insertions, 0 deletions
diff --git a/crypto/cipher.c b/crypto/cipher.c
new file mode 100644
index 000000000..39541e0e5
--- /dev/null
+++ b/crypto/cipher.c
@@ -0,0 +1,122 @@
+/*
+ * Cryptographic API.
+ *
+ * Cipher operations.
+ *
+ * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
+ * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
+ *
+ * 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/kernel.h>
+#include <linux/crypto.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include "internal.h"
+
+static int setkey_unaligned(struct crypto_tfm *tfm, const u8 *key,
+ unsigned int keylen)
+{
+ struct cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
+ unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
+ int ret;
+ u8 *buffer, *alignbuffer;
+ unsigned long absize;
+
+ absize = keylen + alignmask;
+ buffer = kmalloc(absize, GFP_ATOMIC);
+ if (!buffer)
+ return -ENOMEM;
+
+ alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
+ memcpy(alignbuffer, key, keylen);
+ ret = cia->cia_setkey(tfm, alignbuffer, keylen);
+ memset(alignbuffer, 0, keylen);
+ kfree(buffer);
+ return ret;
+
+}
+
+static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
+{
+ struct cipher_alg *cia = &tfm->__crt_alg->cra_cipher;
+ unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
+
+ tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;
+ if (keylen < cia->cia_min_keysize || keylen > cia->cia_max_keysize) {
+ tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
+ return -EINVAL;
+ }
+
+ if ((unsigned long)key & alignmask)
+ return setkey_unaligned(tfm, key, keylen);
+
+ return cia->cia_setkey(tfm, key, keylen);
+}
+
+static void cipher_crypt_unaligned(void (*fn)(struct crypto_tfm *, u8 *,
+ const u8 *),
+ struct crypto_tfm *tfm,
+ u8 *dst, const u8 *src)
+{
+ unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
+ unsigned int size = crypto_tfm_alg_blocksize(tfm);
+ u8 buffer[size + alignmask];
+ u8 *tmp = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
+
+ memcpy(tmp, src, size);
+ fn(tfm, tmp, tmp);
+ memcpy(dst, tmp, size);
+}
+
+static void cipher_encrypt_unaligned(struct crypto_tfm *tfm,
+ u8 *dst, const u8 *src)
+{
+ unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
+ struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
+
+ if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) {
+ cipher_crypt_unaligned(cipher->cia_encrypt, tfm, dst, src);
+ return;
+ }
+
+ cipher->cia_encrypt(tfm, dst, src);
+}
+
+static void cipher_decrypt_unaligned(struct crypto_tfm *tfm,
+ u8 *dst, const u8 *src)
+{
+ unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
+ struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
+
+ if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) {
+ cipher_crypt_unaligned(cipher->cia_decrypt, tfm, dst, src);
+ return;
+ }
+
+ cipher->cia_decrypt(tfm, dst, src);
+}
+
+int crypto_init_cipher_ops(struct crypto_tfm *tfm)
+{
+ struct cipher_tfm *ops = &tfm->crt_cipher;
+ struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
+
+ ops->cit_setkey = setkey;
+ ops->cit_encrypt_one = crypto_tfm_alg_alignmask(tfm) ?
+ cipher_encrypt_unaligned : cipher->cia_encrypt;
+ ops->cit_decrypt_one = crypto_tfm_alg_alignmask(tfm) ?
+ cipher_decrypt_unaligned : cipher->cia_decrypt;
+
+ return 0;
+}
+
+void crypto_exit_cipher_ops(struct crypto_tfm *tfm)
+{
+}