[CRYPTO] api: Add aead crypto type

[pandora-kernel.git] / crypto / aead.c

diff --git a/crypto/aead.c b/crypto/aead.c
new file mode 100644 (file)
index 0000000..84a3501
--- /dev/null
+++ b/crypto/aead.c
@@ -0,0 +1,101 @@
+/*
+ * AEAD: Authenticated Encryption with Associated Data
+ * 
+ * This file provides API support for AEAD algorithms.
+ *
+ * Copyright (c) 2007 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 <crypto/algapi.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/seq_file.h>
+
+static int setkey_unaligned(struct crypto_aead *tfm, const u8 *key,
+                           unsigned int keylen)
+{
+       struct aead_alg *aead = crypto_aead_alg(tfm);
+       unsigned long alignmask = crypto_aead_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 = aead->setkey(tfm, alignbuffer, keylen);
+       memset(alignbuffer, 0, keylen);
+       kfree(buffer);
+       return ret;
+}
+
+static int setkey(struct crypto_aead *tfm, const u8 *key, unsigned int keylen)
+{
+       struct aead_alg *aead = crypto_aead_alg(tfm);
+       unsigned long alignmask = crypto_aead_alignmask(tfm);
+
+       if ((unsigned long)key & alignmask)
+               return setkey_unaligned(tfm, key, keylen);
+
+       return aead->setkey(tfm, key, keylen);
+}
+
+static unsigned int crypto_aead_ctxsize(struct crypto_alg *alg, u32 type,
+                                       u32 mask)
+{
+       return alg->cra_ctxsize;
+}
+
+static int crypto_init_aead_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
+{
+       struct aead_alg *alg = &tfm->__crt_alg->cra_aead;
+       struct aead_tfm *crt = &tfm->crt_aead;
+
+       if (max(alg->authsize, alg->ivsize) > PAGE_SIZE / 8)
+               return -EINVAL;
+
+       crt->setkey = setkey;
+       crt->encrypt = alg->encrypt;
+       crt->decrypt = alg->decrypt;
+       crt->ivsize = alg->ivsize;
+       crt->authsize = alg->authsize;
+
+       return 0;
+}
+
+static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
+       __attribute__ ((unused));
+static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
+{
+       struct aead_alg *aead = &alg->cra_aead;
+
+       seq_printf(m, "type         : aead\n");
+       seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
+       seq_printf(m, "ivsize       : %u\n", aead->ivsize);
+       seq_printf(m, "authsize     : %u\n", aead->authsize);
+}
+
+const struct crypto_type crypto_aead_type = {
+       .ctxsize = crypto_aead_ctxsize,
+       .init = crypto_init_aead_ops,
+#ifdef CONFIG_PROC_FS
+       .show = crypto_aead_show,
+#endif
+};
+EXPORT_SYMBOL_GPL(crypto_aead_type);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Authenticated Encryption with Associated Data (AEAD)");