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linux/crypto/ccm.c
Eric Biggers cd900f0cac crypto: aead - pass instance to crypto_grab_aead() 
Initializing a crypto_aead_spawn currently requires:

1. Set spawn->base.inst to point to the instance.
2. Call crypto_grab_aead().

But there's no reason for these steps to be separate, and in fact this
unneeded complication has caused at least one bug, the one fixed by
commit 6db4341017 ("crypto: adiantum - initialize crypto_spawn::inst")

So just make crypto_grab_aead() take the instance as an argument.

To keep the function calls from getting too unwieldy due to this extra
argument, also introduce a 'mask' variable into the affected places
which weren't already using one.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09 11:30:54 +08:00

1004 lines
24 KiB
C
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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* CCM: Counter with CBC-MAC
*
* (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com>
*/
#include <crypto/internal/aead.h>
#include <crypto/internal/hash.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_ahash_spawn mac;
};
struct crypto_ccm_ctx {
struct crypto_ahash *mac;
struct crypto_skcipher *ctr;
};
struct crypto_rfc4309_ctx {
struct crypto_aead *child;
u8 nonce[3];
};
struct crypto_rfc4309_req_ctx {
struct scatterlist src[3];
struct scatterlist dst[3];
struct aead_request subreq;
};
struct crypto_ccm_req_priv_ctx {
u8 odata[16];
u8 idata[16];
u8 auth_tag[16];
u32 flags;
struct scatterlist src[3];
struct scatterlist dst[3];
union {
struct ahash_request ahreq;
struct skcipher_request skreq;
};
};
struct cbcmac_tfm_ctx {
struct crypto_cipher *child;
};
struct cbcmac_desc_ctx {
unsigned int len;
};
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_skcipher *ctr = ctx->ctr;
struct crypto_ahash *mac = ctx->mac;
int err;
crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK);
crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) &
CRYPTO_TFM_REQ_MASK);
err = crypto_skcipher_setkey(ctr, key, keylen);
if (err)
return err;
crypto_ahash_clear_flags(mac, CRYPTO_TFM_REQ_MASK);
crypto_ahash_set_flags(mac, crypto_aead_get_flags(aead) &
CRYPTO_TFM_REQ_MASK);
return crypto_ahash_setkey(mac, key, keylen);
}
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 int crypto_ccm_auth(struct aead_request *req, struct scatterlist *plain,
unsigned int cryptlen)
{
struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_ccm_ctx *ctx = crypto_aead_ctx(aead);
struct ahash_request *ahreq = &pctx->ahreq;
unsigned int assoclen = req->assoclen;
struct scatterlist sg[3];
u8 *odata = pctx->odata;
u8 *idata = pctx->idata;
int ilen, err;
/* format control data for input */
err = format_input(odata, req, cryptlen);
if (err)
goto out;
sg_init_table(sg, 3);
sg_set_buf(&sg[0], odata, 16);
/* format associated data and compute into mac */
if (assoclen) {
ilen = format_adata(idata, assoclen);
sg_set_buf(&sg[1], idata, ilen);
sg_chain(sg, 3, req->src);
} else {
ilen = 0;
sg_chain(sg, 2, req->src);
}
ahash_request_set_tfm(ahreq, ctx->mac);
ahash_request_set_callback(ahreq, pctx->flags, NULL, NULL);
ahash_request_set_crypt(ahreq, sg, NULL, assoclen + ilen + 16);
err = crypto_ahash_init(ahreq);
if (err)
goto out;
err = crypto_ahash_update(ahreq);
if (err)
goto out;
/* we need to pad the MAC input to a round multiple of the block size */
ilen = 16 - (assoclen + ilen) % 16;
if (ilen < 16) {
memset(idata, 0, ilen);
sg_init_table(sg, 2);
sg_set_buf(&sg[0], idata, ilen);
if (plain)
sg_chain(sg, 2, plain);
plain = sg;
cryptlen += ilen;
}
ahash_request_set_crypt(ahreq, plain, pctx->odata, cryptlen);
err = crypto_ahash_finup(ahreq);
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->assoclen + 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_init_crypt(struct aead_request *req, u8 *tag)
{
struct crypto_ccm_req_priv_ctx *pctx = crypto_ccm_reqctx(req);
struct scatterlist *sg;
u8 *iv = req->iv;
int err;
err = crypto_ccm_check_iv(iv);
if (err)
return err;
pctx->flags = aead_request_flags(req);
/* 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, 3);
sg_set_buf(pctx->src, tag, 16);
sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen);
if (sg != pctx->src + 1)
sg_chain(pctx->src, 2, sg);
if (req->src != req->dst) {
sg_init_table(pctx->dst, 3);
sg_set_buf(pctx->dst, tag, 16);
sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen);
if (sg != pctx->dst + 1)
sg_chain(pctx->dst, 2, sg);
}
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 skcipher_request *skreq = &pctx->skreq;
struct scatterlist *dst;
unsigned int cryptlen = req->cryptlen;
u8 *odata = pctx->odata;
u8 *iv = req->iv;
int err;
err = crypto_ccm_init_crypt(req, odata);
if (err)
return err;
err = crypto_ccm_auth(req, sg_next(pctx->src), cryptlen);
if (err)
return err;
dst = pctx->src;
if (req->src != req->dst)
dst = pctx->dst;
skcipher_request_set_tfm(skreq, ctx->ctr);
skcipher_request_set_callback(skreq, pctx->flags,
crypto_ccm_encrypt_done, req);
skcipher_request_set_crypt(skreq, pctx->src, dst, cryptlen + 16, iv);
err = crypto_skcipher_encrypt(skreq);
if (err)
return err;
/* copy authtag to end of dst */
scatterwalk_map_and_copy(odata, sg_next(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;
struct scatterlist *dst;
pctx->flags = 0;
dst = sg_next(req->src == req->dst ? pctx->src : pctx->dst);
if (!err) {
err = crypto_ccm_auth(req, dst, cryptlen);
if (!err && crypto_memneq(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 skcipher_request *skreq = &pctx->skreq;
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 = pctx->idata;
int err;
cryptlen -= authsize;
err = crypto_ccm_init_crypt(req, authtag);
if (err)
return err;
scatterwalk_map_and_copy(authtag, sg_next(pctx->src), cryptlen,
authsize, 0);
dst = pctx->src;
if (req->src != req->dst)
dst = pctx->dst;
memcpy(iv, req->iv, 16);
skcipher_request_set_tfm(skreq, ctx->ctr);
skcipher_request_set_callback(skreq, pctx->flags,
crypto_ccm_decrypt_done, req);
skcipher_request_set_crypt(skreq, pctx->src, dst, cryptlen + 16, iv);
err = crypto_skcipher_decrypt(skreq);
if (err)
return err;
err = crypto_ccm_auth(req, sg_next(dst), cryptlen);
if (err)
return err;
/* verify */
if (crypto_memneq(authtag, odata, authsize))
return -EBADMSG;
return err;
}
static int crypto_ccm_init_tfm(struct crypto_aead *tfm)
{
struct aead_instance *inst = aead_alg_instance(tfm);
struct ccm_instance_ctx *ictx = aead_instance_ctx(inst);
struct crypto_ccm_ctx *ctx = crypto_aead_ctx(tfm);
struct crypto_ahash *mac;
struct crypto_skcipher *ctr;
unsigned long align;
int err;
mac = crypto_spawn_ahash(&ictx->mac);
if (IS_ERR(mac))
return PTR_ERR(mac);
ctr = crypto_spawn_skcipher(&ictx->ctr);
err = PTR_ERR(ctr);
if (IS_ERR(ctr))
goto err_free_mac;
ctx->mac = mac;
ctx->ctr = ctr;
align = crypto_aead_alignmask(tfm);
align &= ~(crypto_tfm_ctx_alignment() - 1);
crypto_aead_set_reqsize(
tfm,
align + sizeof(struct crypto_ccm_req_priv_ctx) +
max(crypto_ahash_reqsize(mac), crypto_skcipher_reqsize(ctr)));
return 0;
err_free_mac:
crypto_free_ahash(mac);
return err;
}
static void crypto_ccm_exit_tfm(struct crypto_aead *tfm)
{
struct crypto_ccm_ctx *ctx = crypto_aead_ctx(tfm);
crypto_free_ahash(ctx->mac);
crypto_free_skcipher(ctx->ctr);
}
static void crypto_ccm_free(struct aead_instance *inst)
{
struct ccm_instance_ctx *ctx = aead_instance_ctx(inst);
crypto_drop_ahash(&ctx->mac);
crypto_drop_skcipher(&ctx->ctr);
kfree(inst);
}
static int crypto_ccm_create_common(struct crypto_template *tmpl,
struct rtattr **tb,
const char *ctr_name,
const char *mac_name)
{
struct crypto_attr_type *algt;
u32 mask;
struct aead_instance *inst;
struct skcipher_alg *ctr;
struct crypto_alg *mac_alg;
struct hash_alg_common *mac;
struct ccm_instance_ctx *ictx;
int err;
algt = crypto_get_attr_type(tb);
if (IS_ERR(algt))
return PTR_ERR(algt);
if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
return -EINVAL;
mask = crypto_requires_sync(algt->type, algt->mask);
mac_alg = crypto_find_alg(mac_name, &crypto_ahash_type,
CRYPTO_ALG_TYPE_HASH,
CRYPTO_ALG_TYPE_AHASH_MASK |
CRYPTO_ALG_ASYNC);
if (IS_ERR(mac_alg))
return PTR_ERR(mac_alg);
mac = __crypto_hash_alg_common(mac_alg);
err = -EINVAL;
if (strncmp(mac->base.cra_name, "cbcmac(", 7) != 0 ||
mac->digestsize != 16)
goto out_put_mac;
inst = kzalloc(sizeof(*inst) + sizeof(*ictx), GFP_KERNEL);
err = -ENOMEM;
if (!inst)
goto out_put_mac;
ictx = aead_instance_ctx(inst);
err = crypto_init_ahash_spawn(&ictx->mac, mac,
aead_crypto_instance(inst));
if (err)
goto err_free_inst;
err = crypto_grab_skcipher(&ictx->ctr, aead_crypto_instance(inst),
ctr_name, 0, mask);
if (err)
goto err_drop_mac;
ctr = crypto_spawn_skcipher_alg(&ictx->ctr);
/* The skcipher algorithm must be CTR mode, using 16-byte blocks. */
err = -EINVAL;
if (strncmp(ctr->base.cra_name, "ctr(", 4) != 0 ||
crypto_skcipher_alg_ivsize(ctr) != 16 ||
ctr->base.cra_blocksize != 1)
goto err_drop_ctr;
/* ctr and cbcmac must use the same underlying block cipher. */
if (strcmp(ctr->base.cra_name + 4, mac->base.cra_name + 7) != 0)
goto err_drop_ctr;
err = -ENAMETOOLONG;
if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
"ccm(%s", ctr->base.cra_name + 4) >= CRYPTO_MAX_ALG_NAME)
goto err_drop_ctr;
if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
"ccm_base(%s,%s)", ctr->base.cra_driver_name,
mac->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
goto err_drop_ctr;
inst->alg.base.cra_flags = ctr->base.cra_flags & CRYPTO_ALG_ASYNC;
inst->alg.base.cra_priority = (mac->base.cra_priority +
ctr->base.cra_priority) / 2;
inst->alg.base.cra_blocksize = 1;
inst->alg.base.cra_alignmask = mac->base.cra_alignmask |
ctr->base.cra_alignmask;
inst->alg.ivsize = 16;
inst->alg.chunksize = crypto_skcipher_alg_chunksize(ctr);
inst->alg.maxauthsize = 16;
inst->alg.base.cra_ctxsize = sizeof(struct crypto_ccm_ctx);
inst->alg.init = crypto_ccm_init_tfm;
inst->alg.exit = crypto_ccm_exit_tfm;
inst->alg.setkey = crypto_ccm_setkey;
inst->alg.setauthsize = crypto_ccm_setauthsize;
inst->alg.encrypt = crypto_ccm_encrypt;
inst->alg.decrypt = crypto_ccm_decrypt;
inst->free = crypto_ccm_free;
err = aead_register_instance(tmpl, inst);
if (err)
goto err_drop_ctr;
out_put_mac:
crypto_mod_put(mac_alg);
return err;
err_drop_ctr:
crypto_drop_skcipher(&ictx->ctr);
err_drop_mac:
crypto_drop_ahash(&ictx->mac);
err_free_inst:
kfree(inst);
goto out_put_mac;
}
static int crypto_ccm_create(struct crypto_template *tmpl, struct rtattr **tb)
{
const char *cipher_name;
char ctr_name[CRYPTO_MAX_ALG_NAME];
char mac_name[CRYPTO_MAX_ALG_NAME];
cipher_name = crypto_attr_alg_name(tb[1]);
if (IS_ERR(cipher_name))
return PTR_ERR(cipher_name);
if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)",
cipher_name) >= CRYPTO_MAX_ALG_NAME)
return -ENAMETOOLONG;
if (snprintf(mac_name, CRYPTO_MAX_ALG_NAME, "cbcmac(%s)",
cipher_name) >= CRYPTO_MAX_ALG_NAME)
return -ENAMETOOLONG;
return crypto_ccm_create_common(tmpl, tb, ctr_name, mac_name);
}
static int crypto_ccm_base_create(struct crypto_template *tmpl,
struct rtattr **tb)
{
const char *ctr_name;
const char *mac_name;
ctr_name = crypto_attr_alg_name(tb[1]);
if (IS_ERR(ctr_name))
return PTR_ERR(ctr_name);
mac_name = crypto_attr_alg_name(tb[2]);
if (IS_ERR(mac_name))
return PTR_ERR(mac_name);
return crypto_ccm_create_common(tmpl, tb, ctr_name, mac_name);
}
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;
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);
return crypto_aead_setkey(child, key, keylen);
}
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 crypto_rfc4309_req_ctx *rctx = aead_request_ctx(req);
struct aead_request *subreq = &rctx->subreq;
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(aead);
struct crypto_aead *child = ctx->child;
struct scatterlist *sg;
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);
scatterwalk_map_and_copy(iv + 16, req->src, 0, req->assoclen - 8, 0);
sg_init_table(rctx->src, 3);
sg_set_buf(rctx->src, iv + 16, req->assoclen - 8);
sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen);
if (sg != rctx->src + 1)
sg_chain(rctx->src, 2, sg);
if (req->src != req->dst) {
sg_init_table(rctx->dst, 3);
sg_set_buf(rctx->dst, iv + 16, req->assoclen - 8);
sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen);
if (sg != rctx->dst + 1)
sg_chain(rctx->dst, 2, sg);
}
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, rctx->src,
req->src == req->dst ? rctx->src : rctx->dst,
req->cryptlen, iv);
aead_request_set_ad(subreq, req->assoclen - 8);
return subreq;
}
static int crypto_rfc4309_encrypt(struct aead_request *req)
{
if (req->assoclen != 16 && req->assoclen != 20)
return -EINVAL;
req = crypto_rfc4309_crypt(req);
return crypto_aead_encrypt(req);
}
static int crypto_rfc4309_decrypt(struct aead_request *req)
{
if (req->assoclen != 16 && req->assoclen != 20)
return -EINVAL;
req = crypto_rfc4309_crypt(req);
return crypto_aead_decrypt(req);
}
static int crypto_rfc4309_init_tfm(struct crypto_aead *tfm)
{
struct aead_instance *inst = aead_alg_instance(tfm);
struct crypto_aead_spawn *spawn = aead_instance_ctx(inst);
struct crypto_rfc4309_ctx *ctx = crypto_aead_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);
crypto_aead_set_reqsize(
tfm,
sizeof(struct crypto_rfc4309_req_ctx) +
ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
align + 32);
return 0;
}
static void crypto_rfc4309_exit_tfm(struct crypto_aead *tfm)
{
struct crypto_rfc4309_ctx *ctx = crypto_aead_ctx(tfm);
crypto_free_aead(ctx->child);
}
static void crypto_rfc4309_free(struct aead_instance *inst)
{
crypto_drop_aead(aead_instance_ctx(inst));
kfree(inst);
}
static int crypto_rfc4309_create(struct crypto_template *tmpl,
struct rtattr **tb)
{
struct crypto_attr_type *algt;
u32 mask;
struct aead_instance *inst;
struct crypto_aead_spawn *spawn;
struct aead_alg *alg;
const char *ccm_name;
int err;
algt = crypto_get_attr_type(tb);
if (IS_ERR(algt))
return PTR_ERR(algt);
if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
return -EINVAL;
mask = crypto_requires_sync(algt->type, algt->mask);
ccm_name = crypto_attr_alg_name(tb[1]);
if (IS_ERR(ccm_name))
return PTR_ERR(ccm_name);
inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
if (!inst)
return -ENOMEM;
spawn = aead_instance_ctx(inst);
err = crypto_grab_aead(spawn, aead_crypto_instance(inst),
ccm_name, 0, mask);
if (err)
goto out_free_inst;
alg = crypto_spawn_aead_alg(spawn);
err = -EINVAL;
/* We only support 16-byte blocks. */
if (crypto_aead_alg_ivsize(alg) != 16)
goto out_drop_alg;
/* Not a stream cipher? */
if (alg->base.cra_blocksize != 1)
goto out_drop_alg;
err = -ENAMETOOLONG;
if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
"rfc4309(%s)", alg->base.cra_name) >=
CRYPTO_MAX_ALG_NAME ||
snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
"rfc4309(%s)", alg->base.cra_driver_name) >=
CRYPTO_MAX_ALG_NAME)
goto out_drop_alg;
inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
inst->alg.base.cra_priority = alg->base.cra_priority;
inst->alg.base.cra_blocksize = 1;
inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
inst->alg.ivsize = 8;
inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
inst->alg.maxauthsize = 16;
inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4309_ctx);
inst->alg.init = crypto_rfc4309_init_tfm;
inst->alg.exit = crypto_rfc4309_exit_tfm;
inst->alg.setkey = crypto_rfc4309_setkey;
inst->alg.setauthsize = crypto_rfc4309_setauthsize;
inst->alg.encrypt = crypto_rfc4309_encrypt;
inst->alg.decrypt = crypto_rfc4309_decrypt;
inst->free = crypto_rfc4309_free;
err = aead_register_instance(tmpl, inst);
if (err)
goto out_drop_alg;
out:
return err;
out_drop_alg:
crypto_drop_aead(spawn);
out_free_inst:
kfree(inst);
goto out;
}
static int crypto_cbcmac_digest_setkey(struct crypto_shash *parent,
const u8 *inkey, unsigned int keylen)
{
struct cbcmac_tfm_ctx *ctx = crypto_shash_ctx(parent);
return crypto_cipher_setkey(ctx->child, inkey, keylen);
}
static int crypto_cbcmac_digest_init(struct shash_desc *pdesc)
{
struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
int bs = crypto_shash_digestsize(pdesc->tfm);
u8 *dg = (u8 *)ctx + crypto_shash_descsize(pdesc->tfm) - bs;
ctx->len = 0;
memset(dg, 0, bs);
return 0;
}
static int crypto_cbcmac_digest_update(struct shash_desc *pdesc, const u8 *p,
unsigned int len)
{
struct crypto_shash *parent = pdesc->tfm;
struct cbcmac_tfm_ctx *tctx = crypto_shash_ctx(parent);
struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
struct crypto_cipher *tfm = tctx->child;
int bs = crypto_shash_digestsize(parent);
u8 *dg = (u8 *)ctx + crypto_shash_descsize(parent) - bs;
while (len > 0) {
unsigned int l = min(len, bs - ctx->len);
crypto_xor(dg + ctx->len, p, l);
ctx->len +=l;
len -= l;
p += l;
if (ctx->len == bs) {
crypto_cipher_encrypt_one(tfm, dg, dg);
ctx->len = 0;
}
}
return 0;
}
static int crypto_cbcmac_digest_final(struct shash_desc *pdesc, u8 *out)
{
struct crypto_shash *parent = pdesc->tfm;
struct cbcmac_tfm_ctx *tctx = crypto_shash_ctx(parent);
struct cbcmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
struct crypto_cipher *tfm = tctx->child;
int bs = crypto_shash_digestsize(parent);
u8 *dg = (u8 *)ctx + crypto_shash_descsize(parent) - bs;
if (ctx->len)
crypto_cipher_encrypt_one(tfm, dg, dg);
memcpy(out, dg, bs);
return 0;
}
static int cbcmac_init_tfm(struct crypto_tfm *tfm)
{
struct crypto_cipher *cipher;
struct crypto_instance *inst = (void *)tfm->__crt_alg;
struct crypto_spawn *spawn = crypto_instance_ctx(inst);
struct cbcmac_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
cipher = crypto_spawn_cipher(spawn);
if (IS_ERR(cipher))
return PTR_ERR(cipher);
ctx->child = cipher;
return 0;
};
static void cbcmac_exit_tfm(struct crypto_tfm *tfm)
{
struct cbcmac_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
crypto_free_cipher(ctx->child);
}
static int cbcmac_create(struct crypto_template *tmpl, struct rtattr **tb)
{
struct shash_instance *inst;
struct crypto_alg *alg;
int err;
err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH);
if (err)
return err;
alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER,
CRYPTO_ALG_TYPE_MASK);
if (IS_ERR(alg))
return PTR_ERR(alg);
inst = shash_alloc_instance("cbcmac", alg);
err = PTR_ERR(inst);
if (IS_ERR(inst))
goto out_put_alg;
err = crypto_init_spawn(shash_instance_ctx(inst), alg,
shash_crypto_instance(inst),
CRYPTO_ALG_TYPE_MASK);
if (err)
goto out_free_inst;
inst->alg.base.cra_priority = alg->cra_priority;
inst->alg.base.cra_blocksize = 1;
inst->alg.digestsize = alg->cra_blocksize;
inst->alg.descsize = ALIGN(sizeof(struct cbcmac_desc_ctx),
alg->cra_alignmask + 1) +
alg->cra_blocksize;
inst->alg.base.cra_ctxsize = sizeof(struct cbcmac_tfm_ctx);
inst->alg.base.cra_init = cbcmac_init_tfm;
inst->alg.base.cra_exit = cbcmac_exit_tfm;
inst->alg.init = crypto_cbcmac_digest_init;
inst->alg.update = crypto_cbcmac_digest_update;
inst->alg.final = crypto_cbcmac_digest_final;
inst->alg.setkey = crypto_cbcmac_digest_setkey;
err = shash_register_instance(tmpl, inst);
out_free_inst:
if (err)
shash_free_instance(shash_crypto_instance(inst));
out_put_alg:
crypto_mod_put(alg);
return err;
}
static struct crypto_template crypto_ccm_tmpls[] = {
{
.name = "cbcmac",
.create = cbcmac_create,
.free = shash_free_instance,
.module = THIS_MODULE,
}, {
.name = "ccm_base",
.create = crypto_ccm_base_create,
.module = THIS_MODULE,
}, {
.name = "ccm",
.create = crypto_ccm_create,
.module = THIS_MODULE,
}, {
.name = "rfc4309",
.create = crypto_rfc4309_create,
.module = THIS_MODULE,
},
};
static int __init crypto_ccm_module_init(void)
{
return crypto_register_templates(crypto_ccm_tmpls,
ARRAY_SIZE(crypto_ccm_tmpls));
}
static void __exit crypto_ccm_module_exit(void)
{
crypto_unregister_templates(crypto_ccm_tmpls,
ARRAY_SIZE(crypto_ccm_tmpls));
}
subsys_initcall(crypto_ccm_module_init);
module_exit(crypto_ccm_module_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Counter with CBC MAC");
MODULE_ALIAS_CRYPTO("ccm_base");
MODULE_ALIAS_CRYPTO("rfc4309");
MODULE_ALIAS_CRYPTO("ccm");
MODULE_ALIAS_CRYPTO("cbcmac");
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