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/*
* GCM: Galois/Counter Mode.
*
* Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <mh1@iki.fi>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*/
#include <crypto/gf128mul.h>
#include <crypto/internal/aead.h>
#include <crypto/internal/skcipher.h>
#include <crypto/internal/hash.h>
#include <crypto/scatterwalk.h>
#include <crypto/hash.h>
#include "internal.h"
#include <linux/completion.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
struct gcm_instance_ctx {
struct crypto_skcipher_spawn ctr;
struct crypto_ahash_spawn ghash;
};
struct crypto_gcm_ctx {
struct crypto_ablkcipher *ctr;
struct crypto_ahash *ghash;
};
struct crypto_rfc4106_ctx {
struct crypto_aead *child;
u8 nonce[4];
};
struct crypto_rfc4543_ctx {
struct crypto_aead *child;
u8 nonce[4];
};
struct crypto_rfc4543_req_ctx {
u8 auth_tag[16];
struct scatterlist cipher[1];
struct scatterlist payload[2];
struct scatterlist assoc[2];
struct aead_request subreq;
};
struct crypto_gcm_ghash_ctx {
unsigned int cryptlen;
struct scatterlist *src;
void (*complete)(struct aead_request *req, int err);
};
struct crypto_gcm_req_priv_ctx {
u8 auth_tag[16];
u8 iauth_tag[16];
struct scatterlist src[2];
struct scatterlist dst[2];
struct crypto_gcm_ghash_ctx ghash_ctx;
union {
struct ahash_request ahreq;
struct ablkcipher_request abreq;
} u;
};
struct crypto_gcm_setkey_result {
int err;
struct completion completion;
};
static void *gcm_zeroes;
static inline struct crypto_gcm_req_priv_ctx *crypto_gcm_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 void crypto_gcm_setkey_done(struct crypto_async_request *req, int err)
{
struct crypto_gcm_setkey_result *result = req->data;
if (err == -EINPROGRESS)
return;
result->err = err;
complete(&result->completion);
}
static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key,
unsigned int keylen)
{
struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
struct crypto_ahash *ghash = ctx->ghash;
struct crypto_ablkcipher *ctr = ctx->ctr;
struct {
be128 hash;
u8 iv[8];
struct crypto_gcm_setkey_result result;
struct scatterlist sg[1];
struct ablkcipher_request req;
} *data;
int err;
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);
if (err)
return err;
crypto_aead_set_flags(aead, crypto_ablkcipher_get_flags(ctr) &
CRYPTO_TFM_RES_MASK);
data = kzalloc(sizeof(*data) + crypto_ablkcipher_reqsize(ctr),
GFP_KERNEL);
if (!data)
return -ENOMEM;
init_completion(&data->result.completion);
sg_init_one(data->sg, &data->hash, sizeof(data->hash));
ablkcipher_request_set_tfm(&data->req, ctr);
ablkcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP |
CRYPTO_TFM_REQ_MAY_BACKLOG,
crypto_gcm_setkey_done,
&data->result);
ablkcipher_request_set_crypt(&data->req, data->sg, data->sg,
sizeof(data->hash), data->iv);
err = crypto_ablkcipher_encrypt(&data->req);
if (err == -EINPROGRESS || err == -EBUSY) {
err = wait_for_completion_interruptible(
&data->result.completion);
if (!err)
err = data->result.err;
}
if (err)
goto out;
crypto_ahash_clear_flags(ghash, CRYPTO_TFM_REQ_MASK);
crypto_ahash_set_flags(ghash, crypto_aead_get_flags(aead) &
CRYPTO_TFM_REQ_MASK);
err = crypto_ahash_setkey(ghash, (u8 *)&data->hash, sizeof(be128));
crypto_aead_set_flags(aead, crypto_ahash_get_flags(ghash) &
CRYPTO_TFM_RES_MASK);
out:
kfree(data);
return err;
}
static int crypto_gcm_setauthsize(struct crypto_aead *tfm,
unsigned int authsize)
{
switch (authsize) {
case 4:
case 8:
case 12:
case 13:
case 14:
case 15:
case 16:
break;
default:
return -EINVAL;
}
return 0;
}
static void crypto_gcm_init_crypt(struct ablkcipher_request *ablk_req,
struct aead_request *req,
unsigned int cryptlen)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct scatterlist *dst;
__be32 counter = cpu_to_be32(1);
memset(pctx->auth_tag, 0, sizeof(pctx->auth_tag));
memcpy(req->iv + 12, &counter, 4);
sg_init_table(pctx->src, 2);
sg_set_buf(pctx->src, pctx->auth_tag, sizeof(pctx->auth_tag));
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, pctx->auth_tag, sizeof(pctx->auth_tag));
scatterwalk_sg_chain(pctx->dst, 2, req->dst);
dst = pctx->dst;
}
ablkcipher_request_set_tfm(ablk_req, ctx->ctr);
ablkcipher_request_set_crypt(ablk_req, pctx->src, dst,
cryptlen + sizeof(pctx->auth_tag),
req->iv);
}
static inline unsigned int gcm_remain(unsigned int len)
{
len &= 0xfU;
return len ? 16 - len : 0;
}
static void gcm_hash_len_done(struct crypto_async_request *areq, int err);
static void gcm_hash_final_done(struct crypto_async_request *areq, int err);
static int gcm_hash_update(struct aead_request *req,
struct crypto_gcm_req_priv_ctx *pctx,
crypto_completion_t complete,
struct scatterlist *src,
unsigned int len)
{
struct ahash_request *ahreq = &pctx->u.ahreq;
ahash_request_set_callback(ahreq, aead_request_flags(req),
complete, req);
ahash_request_set_crypt(ahreq, src, NULL, len);
return crypto_ahash_update(ahreq);
}
static int gcm_hash_remain(struct aead_request *req,
struct crypto_gcm_req_priv_ctx *pctx,
unsigned int remain,
crypto_completion_t complete)
{
struct ahash_request *ahreq = &pctx->u.ahreq;
ahash_request_set_callback(ahreq, aead_request_flags(req),
complete, req);
sg_init_one(pctx->src, gcm_zeroes, remain);
ahash_request_set_crypt(ahreq, pctx->src, NULL, remain);
return crypto_ahash_update(ahreq);
}
static int gcm_hash_len(struct aead_request *req,
struct crypto_gcm_req_priv_ctx *pctx)
{
struct ahash_request *ahreq = &pctx->u.ahreq;
struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
u128 lengths;
lengths.a = cpu_to_be64(req->assoclen * 8);
lengths.b = cpu_to_be64(gctx->cryptlen * 8);
memcpy(pctx->iauth_tag, &lengths, 16);
sg_init_one(pctx->src, pctx->iauth_tag, 16);
ahash_request_set_callback(ahreq, aead_request_flags(req),
gcm_hash_len_done, req);
ahash_request_set_crypt(ahreq, pctx->src,
NULL, sizeof(lengths));
return crypto_ahash_update(ahreq);
}
static int gcm_hash_final(struct aead_request *req,
struct crypto_gcm_req_priv_ctx *pctx)
{
struct ahash_request *ahreq = &pctx->u.ahreq;
ahash_request_set_callback(ahreq, aead_request_flags(req),
gcm_hash_final_done, req);
ahash_request_set_crypt(ahreq, NULL, pctx->iauth_tag, 0);
return crypto_ahash_final(ahreq);
}
static void __gcm_hash_final_done(struct aead_request *req, int err)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
if (!err)
crypto_xor(pctx->auth_tag, pctx->iauth_tag, 16);
gctx->complete(req, err);
}
static void gcm_hash_final_done(struct crypto_async_request *areq, int err)
{
struct aead_request *req = areq->data;
__gcm_hash_final_done(req, err);
}
static void __gcm_hash_len_done(struct aead_request *req, int err)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
if (!err) {
err = gcm_hash_final(req, pctx);
if (err == -EINPROGRESS || err == -EBUSY)
return;
}
__gcm_hash_final_done(req, err);
}
static void gcm_hash_len_done(struct crypto_async_request *areq, int err)
{
struct aead_request *req = areq->data;
__gcm_hash_len_done(req, err);
}
static void __gcm_hash_crypt_remain_done(struct aead_request *req, int err)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
if (!err) {
err = gcm_hash_len(req, pctx);
if (err == -EINPROGRESS || err == -EBUSY)
return;
}
__gcm_hash_len_done(req, err);
}
static void gcm_hash_crypt_remain_done(struct crypto_async_request *areq,
int err)
{
struct aead_request *req = areq->data;
__gcm_hash_crypt_remain_done(req, err);
}
static void __gcm_hash_crypt_done(struct aead_request *req, int err)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
unsigned int remain;
if (!err) {
remain = gcm_remain(gctx->cryptlen);
BUG_ON(!remain);
err = gcm_hash_remain(req, pctx, remain,
gcm_hash_crypt_remain_done);
if (err == -EINPROGRESS || err == -EBUSY)
return;
}
__gcm_hash_crypt_remain_done(req, err);
}
static void gcm_hash_crypt_done(struct crypto_async_request *areq, int err)
{
struct aead_request *req = areq->data;
__gcm_hash_crypt_done(req, err);
}
static void __gcm_hash_assoc_remain_done(struct aead_request *req, int err)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
crypto_completion_t complete;
unsigned int remain = 0;
if (!err && gctx->cryptlen) {
remain = gcm_remain(gctx->cryptlen);
complete = remain ? gcm_hash_crypt_done :
gcm_hash_crypt_remain_done;
err = gcm_hash_update(req, pctx, complete,
gctx->src, gctx->cryptlen);
if (err == -EINPROGRESS || err == -EBUSY)
return;
}
if (remain)
__gcm_hash_crypt_done(req, err);
else
__gcm_hash_crypt_remain_done(req, err);
}
static void gcm_hash_assoc_remain_done(struct crypto_async_request *areq,
int err)
{
struct aead_request *req = areq->data;
__gcm_hash_assoc_remain_done(req, err);
}
static void __gcm_hash_assoc_done(struct aead_request *req, int err)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
unsigned int remain;
if (!err) {
remain = gcm_remain(req->assoclen);
BUG_ON(!remain);
err = gcm_hash_remain(req, pctx, remain,
gcm_hash_assoc_remain_done);
if (err == -EINPROGRESS || err == -EBUSY)
return;
}
__gcm_hash_assoc_remain_done(req, err);
}
static void gcm_hash_assoc_done(struct crypto_async_request *areq, int err)
{
struct aead_request *req = areq->data;
__gcm_hash_assoc_done(req, err);
}
static void __gcm_hash_init_done(struct aead_request *req, int err)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
crypto_completion_t complete;
unsigned int remain = 0;
if (!err && req->assoclen) {
remain = gcm_remain(req->assoclen);
complete = remain ? gcm_hash_assoc_done :
gcm_hash_assoc_remain_done;
err = gcm_hash_update(req, pctx, complete,
req->assoc, req->assoclen);
if (err == -EINPROGRESS || err == -EBUSY)
return;
}
if (remain)
__gcm_hash_assoc_done(req, err);
else
__gcm_hash_assoc_remain_done(req, err);
}
static void gcm_hash_init_done(struct crypto_async_request *areq, int err)
{
struct aead_request *req = areq->data;
__gcm_hash_init_done(req, err);
}
static int gcm_hash(struct aead_request *req,
struct crypto_gcm_req_priv_ctx *pctx)
{
struct ahash_request *ahreq = &pctx->u.ahreq;
struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
struct crypto_gcm_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
unsigned int remain;
crypto_completion_t complete;
int err;
ahash_request_set_tfm(ahreq, ctx->ghash);
ahash_request_set_callback(ahreq, aead_request_flags(req),
gcm_hash_init_done, req);
err = crypto_ahash_init(ahreq);
if (err)
return err;
remain = gcm_remain(req->assoclen);
complete = remain ? gcm_hash_assoc_done : gcm_hash_assoc_remain_done;
err = gcm_hash_update(req, pctx, complete, req->assoc, req->assoclen);
if (err)
return err;
if (remain) {
err = gcm_hash_remain(req, pctx, remain,
gcm_hash_assoc_remain_done);
if (err)
return err;
}
remain = gcm_remain(gctx->cryptlen);
complete = remain ? gcm_hash_crypt_done : gcm_hash_crypt_remain_done;
err = gcm_hash_update(req, pctx, complete, gctx->src, gctx->cryptlen);
if (err)
return err;
if (remain) {
err = gcm_hash_remain(req, pctx, remain,
gcm_hash_crypt_remain_done);
if (err)
return err;
}
err = gcm_hash_len(req, pctx);
if (err)
return err;
err = gcm_hash_final(req, pctx);
if (err)
return err;
return 0;
}
static void gcm_enc_copy_hash(struct aead_request *req,
struct crypto_gcm_req_priv_ctx *pctx)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
u8 *auth_tag = pctx->auth_tag;
scatterwalk_map_and_copy(auth_tag, req->dst, req->cryptlen,
crypto_aead_authsize(aead), 1);
}
static void gcm_enc_hash_done(struct aead_request *req, int err)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
if (!err)
gcm_enc_copy_hash(req, pctx);
aead_request_complete(req, err);
}
static void gcm_encrypt_done(struct crypto_async_request *areq, int err)
{
struct aead_request *req = areq->data;
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
if (!err) {
err = gcm_hash(req, pctx);
if (err == -EINPROGRESS || err == -EBUSY)
return;
else if (!err) {
crypto_xor(pctx->auth_tag, pctx->iauth_tag, 16);
gcm_enc_copy_hash(req, pctx);
}
}
aead_request_complete(req, err);
}
static int crypto_gcm_encrypt(struct aead_request *req)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct ablkcipher_request *abreq = &pctx->u.abreq;
struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
int err;
crypto_gcm_init_crypt(abreq, req, req->cryptlen);
ablkcipher_request_set_callback(abreq, aead_request_flags(req),
gcm_encrypt_done, req);
gctx->src = req->dst;
gctx->cryptlen = req->cryptlen;
gctx->complete = gcm_enc_hash_done;
err = crypto_ablkcipher_encrypt(abreq);
if (err)
return err;
err = gcm_hash(req, pctx);
if (err)
return err;
crypto_xor(pctx->auth_tag, pctx->iauth_tag, 16);
gcm_enc_copy_hash(req, pctx);
return 0;
}
static int crypto_gcm_verify(struct aead_request *req,
struct crypto_gcm_req_priv_ctx *pctx)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
u8 *auth_tag = pctx->auth_tag;
u8 *iauth_tag = pctx->iauth_tag;
unsigned int authsize = crypto_aead_authsize(aead);
unsigned int cryptlen = req->cryptlen - authsize;
crypto_xor(auth_tag, iauth_tag, 16);
scatterwalk_map_and_copy(iauth_tag, req->src, cryptlen, authsize, 0);
return memcmp(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0;
}
static void gcm_decrypt_done(struct crypto_async_request *areq, int err)
{
struct aead_request *req = areq->data;
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
if (!err)
err = crypto_gcm_verify(req, pctx);
aead_request_complete(req, err);
}
static void gcm_dec_hash_done(struct aead_request *req, int err)
{
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct ablkcipher_request *abreq = &pctx->u.abreq;
struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
if (!err) {
ablkcipher_request_set_callback(abreq, aead_request_flags(req),
gcm_decrypt_done, req);
crypto_gcm_init_crypt(abreq, req, gctx->cryptlen);
err = crypto_ablkcipher_decrypt(abreq);
if (err == -EINPROGRESS || err == -EBUSY)
return;
else if (!err)
err = crypto_gcm_verify(req, pctx);
}
aead_request_complete(req, err);
}
static int crypto_gcm_decrypt(struct aead_request *req)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
struct ablkcipher_request *abreq = &pctx->u.abreq;
struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
unsigned int authsize = crypto_aead_authsize(aead);
unsigned int cryptlen = req->cryptlen;
int err;
if (cryptlen < authsize)
return -EINVAL;
cryptlen -= authsize;
gctx->src = req->src;
gctx->cryptlen = cryptlen;
gctx->complete = gcm_dec_hash_done;
err = gcm_hash(req, pctx);
if (err)
return err;
ablkcipher_request_set_callback(abreq, aead_request_flags(req),
gcm_decrypt_done, req);
crypto_gcm_init_crypt(abreq, req, cryptlen);
err = crypto_ablkcipher_decrypt(abreq);
if (err)
return err;
return crypto_gcm_verify(req, pctx);
}
static int crypto_gcm_init_tfm(struct crypto_tfm *tfm)
{
struct crypto_instance *inst = (void *)tfm->__crt_alg;
struct gcm_instance_ctx *ictx = crypto_instance_ctx(inst);
struct crypto_gcm_ctx *ctx = crypto_tfm_ctx(tfm);
struct crypto_ablkcipher *ctr;
struct crypto_ahash *ghash;
unsigned long align;
int err;
ghash = crypto_spawn_ahash(&ictx->ghash);
if (IS_ERR(ghash))
return PTR_ERR(ghash);
ctr = crypto_spawn_skcipher(&ictx->ctr);
err = PTR_ERR(ctr);
if (IS_ERR(ctr))
goto err_free_hash;
ctx->ctr = ctr;
ctx->ghash = ghash;
align = crypto_tfm_alg_alignmask(tfm);
align &= ~(crypto_tfm_ctx_alignment() - 1);
tfm->crt_aead.reqsize = align +
offsetof(struct crypto_gcm_req_priv_ctx, u) +
max(sizeof(struct ablkcipher_request) +
crypto_ablkcipher_reqsize(ctr),
sizeof(struct ahash_request) +
crypto_ahash_reqsize(ghash));
return 0;
err_free_hash:
crypto_free_ahash(ghash);
return err;
}
static void crypto_gcm_exit_tfm(struct crypto_tfm *tfm)
{
struct crypto_gcm_ctx *ctx = crypto_tfm_ctx(tfm);
crypto_free_ahash(ctx->ghash);
crypto_free_ablkcipher(ctx->ctr);
}
static struct crypto_instance *crypto_gcm_alloc_common(struct rtattr **tb,
const char *full_name,
const char *ctr_name,
const char *ghash_name)
{
struct crypto_attr_type *algt;
struct crypto_instance *inst;
struct crypto_alg *ctr;
struct crypto_alg *ghash_alg;
struct ahash_alg *ghash_ahash_alg;
struct gcm_instance_ctx *ctx;
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);
ghash_alg = crypto_find_alg(ghash_name, &crypto_ahash_type,
CRYPTO_ALG_TYPE_HASH,
CRYPTO_ALG_TYPE_AHASH_MASK);
err = PTR_ERR(ghash_alg);
if (IS_ERR(ghash_alg))
return ERR_PTR(err);
err = -ENOMEM;
inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
if (!inst)
goto out_put_ghash;
ctx = crypto_instance_ctx(inst);
ghash_ahash_alg = container_of(ghash_alg, struct ahash_alg, halg.base);
err = crypto_init_ahash_spawn(&ctx->ghash, &ghash_ahash_alg->halg,
inst);
if (err)
goto err_free_inst;
crypto_set_skcipher_spawn(&ctx->ctr, inst);
err = crypto_grab_skcipher(&ctx->ctr, ctr_name, 0,
crypto_requires_sync(algt->type,
algt->mask));
if (err)
goto err_drop_ghash;
ctr = crypto_skcipher_spawn_alg(&ctx->ctr);
/* We only support 16-byte blocks. */
if (ctr->cra_ablkcipher.ivsize != 16)
goto out_put_ctr;
/* Not a stream cipher? */
err = -EINVAL;
if (ctr->cra_blocksize != 1)
goto out_put_ctr;
err = -ENAMETOOLONG;
if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
"gcm_base(%s,%s)", ctr->cra_driver_name,
ghash_alg->cra_driver_name) >=
CRYPTO_MAX_ALG_NAME)
goto out_put_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 = ctr->cra_priority;
inst->alg.cra_blocksize = 1;
inst->alg.cra_alignmask = ctr->cra_alignmask | (__alignof__(u64) - 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_gcm_ctx);
inst->alg.cra_init = crypto_gcm_init_tfm;
inst->alg.cra_exit = crypto_gcm_exit_tfm;
inst->alg.cra_aead.setkey = crypto_gcm_setkey;
inst->alg.cra_aead.setauthsize = crypto_gcm_setauthsize;
inst->alg.cra_aead.encrypt = crypto_gcm_encrypt;
inst->alg.cra_aead.decrypt = crypto_gcm_decrypt;
out:
crypto_mod_put(ghash_alg);
return inst;
out_put_ctr:
crypto_drop_skcipher(&ctx->ctr);
err_drop_ghash:
crypto_drop_ahash(&ctx->ghash);
err_free_inst:
kfree(inst);
out_put_ghash:
inst = ERR_PTR(err);
goto out;
}
static struct crypto_instance *crypto_gcm_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, "gcm(%s)", cipher_name) >=
CRYPTO_MAX_ALG_NAME)
return ERR_PTR(-ENAMETOOLONG);
return crypto_gcm_alloc_common(tb, full_name, ctr_name, "ghash");
}
static void crypto_gcm_free(struct crypto_instance *inst)
{
struct gcm_instance_ctx *ctx = crypto_instance_ctx(inst);
crypto_drop_skcipher(&ctx->ctr);
crypto_drop_ahash(&ctx->ghash);
kfree(inst);
}
static struct crypto_template crypto_gcm_tmpl = {
.name = "gcm",
.alloc = crypto_gcm_alloc,
.free = crypto_gcm_free,
.module = THIS_MODULE,
};
static struct crypto_instance *crypto_gcm_base_alloc(struct rtattr **tb)
{
int err;
const char *ctr_name;
const char *ghash_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);
ghash_name = crypto_attr_alg_name(tb[2]);
err = PTR_ERR(ghash_name);
if (IS_ERR(ghash_name))
return ERR_PTR(err);
if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm_base(%s,%s)",
ctr_name, ghash_name) >= CRYPTO_MAX_ALG_NAME)
return ERR_PTR(-ENAMETOOLONG);
return crypto_gcm_alloc_common(tb, full_name, ctr_name, ghash_name);
}
static struct crypto_template crypto_gcm_base_tmpl = {
.name = "gcm_base",
.alloc = crypto_gcm_base_alloc,
.free = crypto_gcm_free,
.module = THIS_MODULE,
};
static int crypto_rfc4106_setkey(struct crypto_aead *parent, const u8 *key,
unsigned int keylen)
{
struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
struct crypto_aead *child = ctx->child;
int err;
if (keylen < 4)
return -EINVAL;
keylen -= 4;
memcpy(ctx->nonce, key + keylen, 4);
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_rfc4106_setauthsize(struct crypto_aead *parent,
unsigned int authsize)
{
struct crypto_rfc4106_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_rfc4106_crypt(struct aead_request *req)
{
struct aead_request *subreq = aead_request_ctx(req);
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_rfc4106_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);
memcpy(iv, ctx->nonce, 4);
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_rfc4106_encrypt(struct aead_request *req)
{
req = crypto_rfc4106_crypt(req);
return crypto_aead_encrypt(req);
}
static int crypto_rfc4106_decrypt(struct aead_request *req)
{
req = crypto_rfc4106_crypt(req);
return crypto_aead_decrypt(req);
}
static int crypto_rfc4106_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_rfc4106_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_rfc4106_exit_tfm(struct crypto_tfm *tfm)
{
struct crypto_rfc4106_ctx *ctx = crypto_tfm_ctx(tfm);
crypto_free_aead(ctx->child);
}
static struct crypto_instance *crypto_rfc4106_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,
"rfc4106(%s)", alg->cra_name) >= CRYPTO_MAX_ALG_NAME ||
snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
"rfc4106(%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_rfc4106_ctx);
inst->alg.cra_init = crypto_rfc4106_init_tfm;
inst->alg.cra_exit = crypto_rfc4106_exit_tfm;
inst->alg.cra_aead.setkey = crypto_rfc4106_setkey;
inst->alg.cra_aead.setauthsize = crypto_rfc4106_setauthsize;
inst->alg.cra_aead.encrypt = crypto_rfc4106_encrypt;
inst->alg.cra_aead.decrypt = crypto_rfc4106_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_rfc4106_free(struct crypto_instance *inst)
{
crypto_drop_spawn(crypto_instance_ctx(inst));
kfree(inst);
}
static struct crypto_template crypto_rfc4106_tmpl = {
.name = "rfc4106",
.alloc = crypto_rfc4106_alloc,
.free = crypto_rfc4106_free,
.module = THIS_MODULE,
};
static inline struct crypto_rfc4543_req_ctx *crypto_rfc4543_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 crypto_rfc4543_setkey(struct crypto_aead *parent, const u8 *key,
unsigned int keylen)
{
struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
struct crypto_aead *child = ctx->child;
int err;
if (keylen < 4)
return -EINVAL;
keylen -= 4;
memcpy(ctx->nonce, key + keylen, 4);
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_rfc4543_setauthsize(struct crypto_aead *parent,
unsigned int authsize)
{
struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
if (authsize != 16)
return -EINVAL;
return crypto_aead_setauthsize(ctx->child, authsize);
}
/* this is the same as crypto_authenc_chain */
static void crypto_rfc4543_chain(struct scatterlist *head,
struct scatterlist *sg, int chain)
{
if (chain) {
head->length += sg->length;
sg = scatterwalk_sg_next(sg);
}
if (sg)
scatterwalk_sg_chain(head, 2, sg);
else
sg_mark_end(head);
}
static struct aead_request *crypto_rfc4543_crypt(struct aead_request *req,
int enc)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
struct crypto_rfc4543_req_ctx *rctx = crypto_rfc4543_reqctx(req);
struct aead_request *subreq = &rctx->subreq;
struct scatterlist *dst = req->dst;
struct scatterlist *cipher = rctx->cipher;
struct scatterlist *payload = rctx->payload;
struct scatterlist *assoc = rctx->assoc;
unsigned int authsize = crypto_aead_authsize(aead);
unsigned int assoclen = req->assoclen;
struct page *dstp;
u8 *vdst;
u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child),
crypto_aead_alignmask(ctx->child) + 1);
memcpy(iv, ctx->nonce, 4);
memcpy(iv + 4, req->iv, 8);
/* construct cipher/plaintext */
if (enc)
memset(rctx->auth_tag, 0, authsize);
else
scatterwalk_map_and_copy(rctx->auth_tag, dst,
req->cryptlen - authsize,
authsize, 0);
sg_init_one(cipher, rctx->auth_tag, authsize);
/* construct the aad */
dstp = sg_page(dst);
vdst = PageHighMem(dstp) ? NULL : page_address(dstp) + dst->offset;
sg_init_table(payload, 2);
sg_set_buf(payload, req->iv, 8);
crypto_rfc4543_chain(payload, dst, vdst == req->iv + 8);
assoclen += 8 + req->cryptlen - (enc ? 0 : authsize);
sg_init_table(assoc, 2);
sg_set_page(assoc, sg_page(req->assoc), req->assoc->length,
req->assoc->offset);
crypto_rfc4543_chain(assoc, payload, 0);
aead_request_set_tfm(subreq, ctx->child);
aead_request_set_callback(subreq, req->base.flags, req->base.complete,
req->base.data);
aead_request_set_crypt(subreq, cipher, cipher, enc ? 0 : authsize, iv);
aead_request_set_assoc(subreq, assoc, assoclen);
return subreq;
}
static int crypto_rfc4543_encrypt(struct aead_request *req)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_rfc4543_req_ctx *rctx = crypto_rfc4543_reqctx(req);
struct aead_request *subreq;
int err;
subreq = crypto_rfc4543_crypt(req, 1);
err = crypto_aead_encrypt(subreq);
if (err)
return err;
scatterwalk_map_and_copy(rctx->auth_tag, req->dst, req->cryptlen,
crypto_aead_authsize(aead), 1);
return 0;
}
static int crypto_rfc4543_decrypt(struct aead_request *req)
{
req = crypto_rfc4543_crypt(req, 0);
return crypto_aead_decrypt(req);
}
static int crypto_rfc4543_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_rfc4543_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 crypto_rfc4543_req_ctx) +
ALIGN(crypto_aead_reqsize(aead),
crypto_tfm_ctx_alignment()) +
align + 16;
return 0;
}
static void crypto_rfc4543_exit_tfm(struct crypto_tfm *tfm)
{
struct crypto_rfc4543_ctx *ctx = crypto_tfm_ctx(tfm);
crypto_free_aead(ctx->child);
}
static struct crypto_instance *crypto_rfc4543_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,
"rfc4543(%s)", alg->cra_name) >= CRYPTO_MAX_ALG_NAME ||
snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
"rfc4543(%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_rfc4543_ctx);
inst->alg.cra_init = crypto_rfc4543_init_tfm;
inst->alg.cra_exit = crypto_rfc4543_exit_tfm;
inst->alg.cra_aead.setkey = crypto_rfc4543_setkey;
inst->alg.cra_aead.setauthsize = crypto_rfc4543_setauthsize;
inst->alg.cra_aead.encrypt = crypto_rfc4543_encrypt;
inst->alg.cra_aead.decrypt = crypto_rfc4543_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_rfc4543_free(struct crypto_instance *inst)
{
crypto_drop_spawn(crypto_instance_ctx(inst));
kfree(inst);
}
static struct crypto_template crypto_rfc4543_tmpl = {
.name = "rfc4543",
.alloc = crypto_rfc4543_alloc,
.free = crypto_rfc4543_free,
.module = THIS_MODULE,
};
static int __init crypto_gcm_module_init(void)
{
int err;
gcm_zeroes = kzalloc(16, GFP_KERNEL);
if (!gcm_zeroes)
return -ENOMEM;
err = crypto_register_template(&crypto_gcm_base_tmpl);
if (err)
goto out;
err = crypto_register_template(&crypto_gcm_tmpl);
if (err)
goto out_undo_base;
err = crypto_register_template(&crypto_rfc4106_tmpl);
if (err)
goto out_undo_gcm;
err = crypto_register_template(&crypto_rfc4543_tmpl);
if (err)
goto out_undo_rfc4106;
return 0;
out_undo_rfc4106:
crypto_unregister_template(&crypto_rfc4106_tmpl);
out_undo_gcm:
crypto_unregister_template(&crypto_gcm_tmpl);
out_undo_base:
crypto_unregister_template(&crypto_gcm_base_tmpl);
out:
kfree(gcm_zeroes);
return err;
}
static void __exit crypto_gcm_module_exit(void)
{
kfree(gcm_zeroes);
crypto_unregister_template(&crypto_rfc4543_tmpl);
crypto_unregister_template(&crypto_rfc4106_tmpl);
crypto_unregister_template(&crypto_gcm_tmpl);
crypto_unregister_template(&crypto_gcm_base_tmpl);
}
module_init(crypto_gcm_module_init);
module_exit(crypto_gcm_module_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Galois/Counter Mode");
MODULE_AUTHOR("Mikko Herranen <mh1@iki.fi>");
MODULE_ALIAS("gcm_base");
MODULE_ALIAS("rfc4106");
MODULE_ALIAS("rfc4543");
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