Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
Fetching contributors…

Cannot retrieve contributors at this time

1369 lines (1106 sloc) 35.373 kb
/*
* 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);
}
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);
scatterwalk_crypto_chain(payload, dst, vdst == req->iv + 8, 2);
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);
scatterwalk_crypto_chain(assoc, payload, 0, 2);
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");
Jump to Line
Something went wrong with that request. Please try again.