/* * 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)");