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/*
* CCM: Counter with CBC-MAC
*
* (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com>
*
* 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/internal/aead.h>
#include <crypto/internal/skcipher.h>
#include <crypto/scatterwalk.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include "internal.h"
struct ccm_instance_ctx {
struct crypto_skcipher_spawn ctr;
struct crypto_spawn cipher;
};
struct crypto_ccm_ctx {
struct crypto_cipher *cipher;
struct crypto_ablkcipher *ctr;
};
struct crypto_rfc4309_ctx {
struct crypto_aead *child;
u8 nonce[3];
};
struct crypto_ccm_req_priv_ctx {
u8 odata[16];
u8 idata[16];
u8 auth_tag[16];
u32 ilen;
u32 flags;
struct scatterlist src[2];
struct scatterlist dst[2];
struct ablkcipher_request abreq;
};
static inline struct crypto_ccm_req_priv_ctx *crypto_ccm_reqctx(
struct aead_request *req)
{
unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req));
return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1);
}
static int set_msg_len(u8 *block, unsigned int msglen, int csize)
{
__be32 data;
memset(block, 0, csize);
block += csize;
if (csize >= 4)
csize = 4;
else if (msglen > (1 << (8 * csize)))
return -EOVERFLOW;
data = cpu_to_be32(msglen);
memcpy(block - csize, (u8 *)&data + 4 - csize, csize);
return 0;
}
static int crypto_ccm_setkey(struct crypto_aead *aead, const u8 *key,
unsigned int keylen)
{
struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
struct crypto_ablkcipher *ctr = ctx->ctr;
struct crypto_cipher *tfm = ctx->cipher;
int err = 0;
crypto_ablkcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK);
crypto_ablkcipher_set_flags(ctr, crypto_aead_get_flags(aead) &
CRYPTO_TFM_REQ_MASK);
err = crypto_ablkcipher_setkey(ctr, key, keylen);
crypto_aead_set_flags(aead, crypto_ablkcipher_get_flags(ctr) &
CRYPTO_TFM_RES_MASK);
if (err)
goto out;
crypto_cipher_clear_flags(tfm, CRYPTO_TFM_REQ_MASK);
crypto_cipher_set_flags(tfm, crypto_aead_get_flags(aead) &
CRYPTO_TFM_REQ_MASK);
err = crypto_cipher_setkey(tfm, key, keylen);
crypto_aead_set_flags(aead, crypto_cipher_get_flags(tfm) &
CRYPTO_TFM_RES_MASK);
out:
return err;
}
static int crypto_ccm_setauthsize(struct crypto_aead *tfm,
unsigned int authsize)
{
switch (authsize) {
case 4:
case 6:
case 8:
case 10:
case 12:
case 14:
case 16:
break;
default:
return -EINVAL;
}
return 0;
}
static int format_input(u8 *info, struct aead_request *req,
unsigned int cryptlen)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
unsigned int lp = req->iv[0];
unsigned int l = lp + 1;
unsigned int m;
m = crypto_aead_authsize(aead);
memcpy(info, req->iv, 16);
/* format control info per RFC 3610 and
* NIST Special Publication 800-38C
*/
*info |= (8 * ((m - 2) / 2));
if (req->assoclen)
*info |= 64;
return set_msg_len(info + 16 - l, cryptlen, l);
}
static int format_adata(u8 *adata, unsigned int a)
{
int len = 0;
/* add control info for associated data
* RFC 3610 and NIST Special Publication 800-38C
*/
if (a < 65280) {
*(__be16 *)adata = cpu_to_be16(a);
len = 2;
} else {
*(__be16 *)adata = cpu_to_be16(0xfffe);
*(__be32 *)&adata[2] = cpu_to_be32(a);
len = 6;
}
return len;
}
static void compute_mac(struct crypto_cipher *tfm, u8 *data, int n,
struct crypto_ccm_req_priv_ctx *pctx)
{
unsigned int bs = 16;
u8 *odata = pctx->odata;
u8 *idata = pctx->idata;
int datalen, getlen;
datalen = n;
/* first time in here, block may be partially filled. */
getlen = bs - pctx->ilen;
if (datalen >= getlen) {
memcpy(idata + pctx->ilen, data, getlen);
crypto_xor(odata, idata, bs);
crypto_cipher_encrypt_one(tfm, odata, odata);
datalen -= getlen;
data += getlen;
pctx->ilen = 0;
}
/* now encrypt rest of data */
while (datalen >= bs) {
crypto_xor(odata, data, bs);
crypto_cipher_encrypt_one(tfm, odata, odata);
datalen -= bs;
data += bs;
}
/* check and see if there's leftover data that wasn't
* enough to fill a block.
*/
if (datalen) {
memcpy(idata + pctx->ilen, data, datalen);
pctx->ilen += datalen;
}
}
static void get_data_to_compute(struct crypto_cipher *tfm,
struct crypto_ccm_req_priv_ctx *pctx,
struct scatterlist *sg, unsigned int len)
{
struct scatter_walk walk;
u8 *data_src;
int n;
scatterwalk_start(&walk, sg);
while (len) {
n = scatterwalk_clamp(&walk, len);
if (!n) {
scatterwalk_start(&walk, sg_next(walk.sg));
n = scatterwalk_clamp(&walk, len);
}
data_src = scatterwalk_map(&walk, 0);
compute_mac(tfm, data_src, n, pctx);
len -= n;
scatterwalk_unmap(data_src, 0);
scatterwalk_advance(&walk, n);
scatterwalk_done(&walk, 0, len);
if (len)
crypto_yield(pctx->flags);
}
/* any leftover needs padding and then encrypted */
if (pctx->ilen) {
int padlen;
u8 *odata = pctx->odata;
u8 *idata = pctx->idata;
padlen = 16 - pctx->ilen;
memset(idata + pctx->ilen, 0, padlen);
crypto_xor(odata, idata, 16);
crypto_cipher_encrypt_one(tfm, odata, odata);
pctx->ilen = 0;
}
}
static int crypto_ccm_auth(struct aead_request *req, struct scatterlist *plain,
unsigned int cryptlen)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
struct crypto_cipher *cipher = ctx->cipher;
unsigned int assoclen = req->assoclen;
u8 *odata = pctx->odata;
u8 *idata = pctx->idata;
int err;
/* format control data for input */
err = format_input(odata, req, cryptlen);
if (err)
goto out;
/* encrypt first block to use as start in computing mac */
crypto_cipher_encrypt_one(cipher, odata, odata);
/* format associated data and compute into mac */
if (assoclen) {
pctx->ilen = format_adata(idata, assoclen);
get_data_to_compute(cipher, pctx, req->assoc, req->assoclen);
} else {
pctx->ilen = 0;
}
/* compute plaintext into mac */
get_data_to_compute(cipher, pctx, plain, cryptlen);
out:
return err;
}
static void crypto_ccm_encrypt_done(struct crypto_async_request *areq, int err)
{
struct aead_request *req = areq->data;
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
u8 *odata = pctx->odata;
if (!err)
scatterwalk_map_and_copy(odata, req->dst, req->cryptlen,
crypto_aead_authsize(aead), 1);
aead_request_complete(req, err);
}
static inline int crypto_ccm_check_iv(const u8 *iv)
{
/* 2 <= L <= 8, so 1 <= L' <= 7. */
if (1 > iv[0] || iv[0] > 7)
return -EINVAL;
return 0;
}
static int crypto_ccm_encrypt(struct aead_request *req)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
struct ablkcipher_request *abreq = &pctx->abreq;
struct scatterlist *dst;
unsigned int cryptlen = req->cryptlen;
u8 *odata = pctx->odata;
u8 *iv = req->iv;
int err;
err = crypto_ccm_check_iv(iv);
if (err)
return err;
pctx->flags = aead_request_flags(req);
err = crypto_ccm_auth(req, req->src, cryptlen);
if (err)
return err;
/* Note: rfc 3610 and NIST 800-38C require counter of
* zero to encrypt auth tag.
*/
memset(iv + 15 - iv[0], 0, iv[0] + 1);
sg_init_table(pctx->src, 2);
sg_set_buf(pctx->src, odata, 16);
scatterwalk_sg_chain(pctx->src, 2, req->src);
dst = pctx->src;
if (req->src != req->dst) {
sg_init_table(pctx->dst, 2);
sg_set_buf(pctx->dst, odata, 16);
scatterwalk_sg_chain(pctx->dst, 2, req->dst);
dst = pctx->dst;
}
ablkcipher_request_set_tfm(abreq, ctx->ctr);
ablkcipher_request_set_callback(abreq, pctx->flags,
crypto_ccm_encrypt_done, req);
ablkcipher_request_set_crypt(abreq, pctx->src, dst, cryptlen + 16, iv);
err = crypto_ablkcipher_encrypt(abreq);
if (err)
return err;
/* copy authtag to end of dst */
scatterwalk_map_and_copy(odata, req->dst, cryptlen,
crypto_aead_authsize(aead), 1);
return err;
}
static void crypto_ccm_decrypt_done(struct crypto_async_request *areq,
int err)
{
struct aead_request *req = areq->data;
struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
struct crypto_aead *aead = crypto_aead_reqtfm(req);
unsigned int authsize = crypto_aead_authsize(aead);
unsigned int cryptlen = req->cryptlen - authsize;
if (!err) {
err = crypto_ccm_auth(req, req->dst, cryptlen);
if (!err && memcmp(pctx->auth_tag, pctx->odata, authsize))
err = -EBADMSG;
}
aead_request_complete(req, err);
}
static int crypto_ccm_decrypt(struct aead_request *req)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
struct ablkcipher_request *abreq = &pctx->abreq;
struct scatterlist *dst;
unsigned int authsize = crypto_aead_authsize(aead);
unsigned int cryptlen = req->cryptlen;
u8 *authtag = pctx->auth_tag;
u8 *odata = pctx->odata;
u8 *iv = req->iv;
int err;
if (cryptlen < authsize)
return -EINVAL;
cryptlen -= authsize;
err = crypto_ccm_check_iv(iv);
if (err)
return err;
pctx->flags = aead_request_flags(req);
scatterwalk_map_and_copy(authtag, req->src, cryptlen, authsize, 0);
memset(iv + 15 - iv[0], 0, iv[0] + 1);
sg_init_table(pctx->src, 2);
sg_set_buf(pctx->src, authtag, 16);
scatterwalk_sg_chain(pctx->src, 2, req->src);
dst = pctx->src;
if (req->src != req->dst) {
sg_init_table(pctx->dst, 2);
sg_set_buf(pctx->dst, authtag, 16);
scatterwalk_sg_chain(pctx->dst, 2, req->dst);
dst = pctx->dst;
}
ablkcipher_request_set_tfm(abreq, ctx->ctr);
ablkcipher_request_set_callback(abreq, pctx->flags,
crypto_ccm_decrypt_done, req);
ablkcipher_request_set_crypt(abreq, pctx->src, dst, cryptlen + 16, iv);
err = crypto_ablkcipher_decrypt(abreq);
if (err)
return err;
err = crypto_ccm_auth(req, req->dst, cryptlen);
if (err)
return err;
/* verify */
if (memcmp(authtag, odata, authsize))
return -EBADMSG;
return err;
}
static int crypto_ccm_init_tfm(struct crypto_tfm *tfm)
{
struct crypto_instance *inst = (void *)tfm->__crt_alg;
struct ccm_instance_ctx *ictx = crypto_instance_ctx(inst);
struct crypto_ccm_ctx *ctx = crypto_tfm_ctx(tfm);
struct crypto_cipher *cipher;
struct crypto_ablkcipher *ctr;
unsigned long align;
int err;
cipher = crypto_spawn_cipher(&ictx->cipher);
if (IS_ERR(cipher))
return PTR_ERR(cipher);
ctr = crypto_spawn_skcipher(&ictx->ctr);
err = PTR_ERR(ctr);
if (IS_ERR(ctr))
goto err_free_cipher;
ctx->cipher = cipher;
ctx->ctr = ctr;
align = crypto_tfm_alg_alignmask(tfm);
align &= ~(crypto_tfm_ctx_alignment() - 1);
tfm->crt_aead.reqsize = align +
sizeof(struct crypto_ccm_req_priv_ctx) +
crypto_ablkcipher_reqsize(ctr);
return 0;
err_free_cipher:
crypto_free_cipher(cipher);
return err;
}
static void crypto_ccm_exit_tfm(struct crypto_tfm *tfm)
{
struct crypto_ccm_ctx *ctx = crypto_tfm_ctx(tfm);
crypto_free_cipher(ctx->cipher);
crypto_free_ablkcipher(ctx->ctr);
}
static struct crypto_instance *crypto_ccm_alloc_common(struct rtattr **tb,
const char *full_name,
const char *ctr_name,
const char *cipher_name)
{
struct crypto_attr_type *algt;
struct crypto_instance *inst;
struct crypto_alg *ctr;
struct crypto_alg *cipher;
struct ccm_instance_ctx *ictx;
int err;
algt = crypto_get_attr_type(tb);
err = PTR_ERR(algt);
if (IS_ERR(algt))
return ERR_PTR(err);
if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
return ERR_PTR(-EINVAL);
cipher = crypto_alg_mod_lookup(cipher_name, CRYPTO_ALG_TYPE_CIPHER,
CRYPTO_ALG_TYPE_MASK);
err = PTR_ERR(cipher);
if (IS_ERR(cipher))
return ERR_PTR(err);
err = -EINVAL;
if (cipher->cra_blocksize != 16)
goto out_put_cipher;
inst = kzalloc(sizeof(*inst) + sizeof(*ictx), GFP_KERNEL);
err = -ENOMEM;
if (!inst)
goto out_put_cipher;
ictx = crypto_instance_ctx(inst);
err = crypto_init_spawn(&ictx->cipher, cipher, inst,
CRYPTO_ALG_TYPE_MASK);
if (err)
goto err_free_inst;
crypto_set_skcipher_spawn(&ictx->ctr, inst);
err = crypto_grab_skcipher(&ictx->ctr, ctr_name, 0,
crypto_requires_sync(algt->type,
algt->mask));
if (err)
goto err_drop_cipher;
ctr = crypto_skcipher_spawn_alg(&ictx->ctr);
/* Not a stream cipher? */
err = -EINVAL;
if (ctr->cra_blocksize != 1)
goto err_drop_ctr;
/* We want the real thing! */
if (ctr->cra_ablkcipher.ivsize != 16)
goto err_drop_ctr;
err = -ENAMETOOLONG;
if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
"ccm_base(%s,%s)", ctr->cra_driver_name,
cipher->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
goto err_drop_ctr;
memcpy(inst->alg.cra_name, full_name, CRYPTO_MAX_ALG_NAME);
inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;
inst->alg.cra_flags |= ctr->cra_flags & CRYPTO_ALG_ASYNC;
inst->alg.cra_priority = cipher->cra_priority + ctr->cra_priority;
inst->alg.cra_blocksize = 1;
inst->alg.cra_alignmask = cipher->cra_alignmask | ctr->cra_alignmask |
(__alignof__(u32) - 1);
inst->alg.cra_type = &crypto_aead_type;
inst->alg.cra_aead.ivsize = 16;
inst->alg.cra_aead.maxauthsize = 16;
inst->alg.cra_ctxsize = sizeof(struct crypto_ccm_ctx);
inst->alg.cra_init = crypto_ccm_init_tfm;
inst->alg.cra_exit = crypto_ccm_exit_tfm;
inst->alg.cra_aead.setkey = crypto_ccm_setkey;
inst->alg.cra_aead.setauthsize = crypto_ccm_setauthsize;
inst->alg.cra_aead.encrypt = crypto_ccm_encrypt;
inst->alg.cra_aead.decrypt = crypto_ccm_decrypt;
out:
crypto_mod_put(cipher);
return inst;
err_drop_ctr:
crypto_drop_skcipher(&ictx->ctr);
err_drop_cipher:
crypto_drop_spawn(&ictx->cipher);
err_free_inst:
kfree(inst);
out_put_cipher:
inst = ERR_PTR(err);
goto out;
}
static struct crypto_instance *crypto_ccm_alloc(struct rtattr **tb)
{
int err;
const char *cipher_name;
char ctr_name[CRYPTO_MAX_ALG_NAME];
char full_name[CRYPTO_MAX_ALG_NAME];
cipher_name = crypto_attr_alg_name(tb[1]);
err = PTR_ERR(cipher_name);
if (IS_ERR(cipher_name))
return ERR_PTR(err);
if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)",
cipher_name) >= CRYPTO_MAX_ALG_NAME)
return ERR_PTR(-ENAMETOOLONG);
if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "ccm(%s)", cipher_name) >=
CRYPTO_MAX_ALG_NAME)
return ERR_PTR(-ENAMETOOLONG);
return crypto_ccm_alloc_common(tb, full_name, ctr_name, cipher_name);
}
static void crypto_ccm_free(struct crypto_instance *inst)
{
struct ccm_instance_ctx *ctx = crypto_instance_ctx(inst);
crypto_drop_spawn(&ctx->cipher);
crypto_drop_skcipher(&ctx->ctr);
kfree(inst);
}
static struct crypto_template crypto_ccm_tmpl = {
.name = "ccm",
.alloc = crypto_ccm_alloc,
.free = crypto_ccm_free,
.module = THIS_MODULE,
};
static struct crypto_instance *crypto_ccm_base_alloc(struct rtattr **tb)
{
int err;
const char *ctr_name;
const char *cipher_name;
char full_name[CRYPTO_MAX_ALG_NAME];
ctr_name = crypto_attr_alg_name(tb[1]);
err = PTR_ERR(ctr_name);
if (IS_ERR(ctr_name))
return ERR_PTR(err);
cipher_name = crypto_attr_alg_name(tb[2]);
err = PTR_ERR(cipher_name);
if (IS_ERR(cipher_name))
return ERR_PTR(err);
if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "ccm_base(%s,%s)",
ctr_name, cipher_name) >= CRYPTO_MAX_ALG_NAME)
return ERR_PTR(-ENAMETOOLONG);
return crypto_ccm_alloc_common(tb, full_name, ctr_name, cipher_name);
}
static struct crypto_template crypto_ccm_base_tmpl = {
.name = "ccm_base",
.alloc = crypto_ccm_base_alloc,
.free = crypto_ccm_free,
.module = THIS_MODULE,
};
static int crypto_rfc4309_setkey(struct crypto_aead *parent, const u8 *key,
unsigned int keylen)
{
struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(parent);
struct crypto_aead *child = ctx->child;
int err;
if (keylen < 3)
return -EINVAL;
keylen -= 3;
memcpy(ctx->nonce, key + keylen, 3);
crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
CRYPTO_TFM_REQ_MASK);
err = crypto_aead_setkey(child, key, keylen);
crypto_aead_set_flags(parent, crypto_aead_get_flags(child) &
CRYPTO_TFM_RES_MASK);
return err;
}
static int crypto_rfc4309_setauthsize(struct crypto_aead *parent,
unsigned int authsize)
{
struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(parent);
switch (authsize) {
case 8:
case 12:
case 16:
break;
default:
return -EINVAL;
}
return crypto_aead_setauthsize(ctx->child, authsize);
}
static struct aead_request *crypto_rfc4309_crypt(struct aead_request *req)
{
struct aead_request *subreq = aead_request_ctx(req);
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(aead);
struct crypto_aead *child = ctx->child;
u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child),
crypto_aead_alignmask(child) + 1);
/* L' */
iv[0] = 3;
memcpy(iv + 1, ctx->nonce, 3);
memcpy(iv + 4, req->iv, 8);
aead_request_set_tfm(subreq, child);
aead_request_set_callback(subreq, req->base.flags, req->base.complete,
req->base.data);
aead_request_set_crypt(subreq, req->src, req->dst, req->cryptlen, iv);
aead_request_set_assoc(subreq, req->assoc, req->assoclen);
return subreq;
}
static int crypto_rfc4309_encrypt(struct aead_request *req)
{
req = crypto_rfc4309_crypt(req);
return crypto_aead_encrypt(req);
}
static int crypto_rfc4309_decrypt(struct aead_request *req)
{
req = crypto_rfc4309_crypt(req);
return crypto_aead_decrypt(req);
}
static int crypto_rfc4309_init_tfm(struct crypto_tfm *tfm)
{
struct crypto_instance *inst = (void *)tfm->__crt_alg;
struct crypto_aead_spawn *spawn = crypto_instance_ctx(inst);
struct crypto_rfc4309_ctx *ctx = crypto_tfm_ctx(tfm);
struct crypto_aead *aead;
unsigned long align;
aead = crypto_spawn_aead(spawn);
if (IS_ERR(aead))
return PTR_ERR(aead);
ctx->child = aead;
align = crypto_aead_alignmask(aead);
align &= ~(crypto_tfm_ctx_alignment() - 1);
tfm->crt_aead.reqsize = sizeof(struct aead_request) +
ALIGN(crypto_aead_reqsize(aead),
crypto_tfm_ctx_alignment()) +
align + 16;
return 0;
}
static void crypto_rfc4309_exit_tfm(struct crypto_tfm *tfm)
{
struct crypto_rfc4309_ctx *ctx = crypto_tfm_ctx(tfm);
crypto_free_aead(ctx->child);
}
static struct crypto_instance *crypto_rfc4309_alloc(struct rtattr **tb)
{
struct crypto_attr_type *algt;
struct crypto_instance *inst;
struct crypto_aead_spawn *spawn;
struct crypto_alg *alg;
const char *ccm_name;
int err;
algt = crypto_get_attr_type(tb);
err = PTR_ERR(algt);
if (IS_ERR(algt))
return ERR_PTR(err);
if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
return ERR_PTR(-EINVAL);
ccm_name = crypto_attr_alg_name(tb[1]);
err = PTR_ERR(ccm_name);
if (IS_ERR(ccm_name))
return ERR_PTR(err);
inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
if (!inst)
return ERR_PTR(-ENOMEM);
spawn = crypto_instance_ctx(inst);
crypto_set_aead_spawn(spawn, inst);
err = crypto_grab_aead(spawn, ccm_name, 0,
crypto_requires_sync(algt->type, algt->mask));
if (err)
goto out_free_inst;
alg = crypto_aead_spawn_alg(spawn);
err = -EINVAL;
/* We only support 16-byte blocks. */
if (alg->cra_aead.ivsize != 16)
goto out_drop_alg;
/* Not a stream cipher? */
if (alg->cra_blocksize != 1)
goto out_drop_alg;
err = -ENAMETOOLONG;
if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
"rfc4309(%s)", alg->cra_name) >= CRYPTO_MAX_ALG_NAME ||
snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
"rfc4309(%s)", alg->cra_driver_name) >=
CRYPTO_MAX_ALG_NAME)
goto out_drop_alg;
inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;
inst->alg.cra_flags |= alg->cra_flags & CRYPTO_ALG_ASYNC;
inst->alg.cra_priority = alg->cra_priority;
inst->alg.cra_blocksize = 1;
inst->alg.cra_alignmask = alg->cra_alignmask;
inst->alg.cra_type = &crypto_nivaead_type;
inst->alg.cra_aead.ivsize = 8;
inst->alg.cra_aead.maxauthsize = 16;
inst->alg.cra_ctxsize = sizeof(struct crypto_rfc4309_ctx);
inst->alg.cra_init = crypto_rfc4309_init_tfm;
inst->alg.cra_exit = crypto_rfc4309_exit_tfm;
inst->alg.cra_aead.setkey = crypto_rfc4309_setkey;
inst->alg.cra_aead.setauthsize = crypto_rfc4309_setauthsize;
inst->alg.cra_aead.encrypt = crypto_rfc4309_encrypt;
inst->alg.cra_aead.decrypt = crypto_rfc4309_decrypt;
inst->alg.cra_aead.geniv = "seqiv";
out:
return inst;
out_drop_alg:
crypto_drop_aead(spawn);
out_free_inst:
kfree(inst);
inst = ERR_PTR(err);
goto out;
}
static void crypto_rfc4309_free(struct crypto_instance *inst)
{
crypto_drop_spawn(crypto_instance_ctx(inst));
kfree(inst);
}
static struct crypto_template crypto_rfc4309_tmpl = {
.name = "rfc4309",
.alloc = crypto_rfc4309_alloc,
.free = crypto_rfc4309_free,
.module = THIS_MODULE,
};
static int __init crypto_ccm_module_init(void)
{
int err;
err = crypto_register_template(&crypto_ccm_base_tmpl);
if (err)
goto out;
err = crypto_register_template(&crypto_ccm_tmpl);
if (err)
goto out_undo_base;
err = crypto_register_template(&crypto_rfc4309_tmpl);
if (err)
goto out_undo_ccm;
out:
return err;
out_undo_ccm:
crypto_unregister_template(&crypto_ccm_tmpl);
out_undo_base:
crypto_unregister_template(&crypto_ccm_base_tmpl);
goto out;
}
static void __exit crypto_ccm_module_exit(void)
{
crypto_unregister_template(&crypto_rfc4309_tmpl);
crypto_unregister_template(&crypto_ccm_tmpl);
crypto_unregister_template(&crypto_ccm_base_tmpl);
}
module_init(crypto_ccm_module_init);
module_exit(crypto_ccm_module_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Counter with CBC MAC");
MODULE_ALIAS("ccm_base");
MODULE_ALIAS("rfc4309");
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