aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--crypto/gcm.c190
1 files changed, 112 insertions, 78 deletions
diff --git a/crypto/gcm.c b/crypto/gcm.c
index c54d478948a..f6bee6f209a 100644
--- a/crypto/gcm.c
+++ b/crypto/gcm.c
@@ -11,6 +11,7 @@
#include <crypto/algapi.h>
#include <crypto/gf128mul.h>
#include <crypto/scatterwalk.h>
+#include <linux/completion.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
@@ -38,11 +39,17 @@ struct crypto_gcm_ghash_ctx {
struct crypto_gcm_req_priv_ctx {
u8 auth_tag[16];
u8 iauth_tag[16];
- u8 counter[16];
+ struct scatterlist src[2];
+ struct scatterlist dst[2];
struct crypto_gcm_ghash_ctx ghash;
struct ablkcipher_request abreq;
};
+struct crypto_gcm_setkey_result {
+ int err;
+ struct completion completion;
+};
+
static inline struct crypto_gcm_req_priv_ctx *crypto_gcm_reqctx(
struct aead_request *req)
{
@@ -158,33 +165,15 @@ static void crypto_gcm_ghash_final_xor(struct crypto_gcm_ghash_ctx *ctx,
crypto_xor(dst, buf, 16);
}
-static inline void crypto_gcm_set_counter(u8 *counterblock, u32 value)
+static void crypto_gcm_setkey_done(struct crypto_async_request *req, int err)
{
- *((u32 *)&counterblock[12]) = cpu_to_be32(value + 1);
-}
+ struct crypto_gcm_setkey_result *result = req->data;
-static int crypto_gcm_encrypt_counter(struct crypto_aead *aead, u8 *block,
- u32 value, const u8 *iv)
-{
- struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
- struct crypto_ablkcipher *ctr = ctx->ctr;
- struct ablkcipher_request req;
- struct scatterlist sg;
- u8 counterblock[16];
-
- if (iv == NULL)
- memset(counterblock, 0, 12);
- else
- memcpy(counterblock, iv, 12);
-
- crypto_gcm_set_counter(counterblock, value);
-
- sg_init_one(&sg, block, 16);
- ablkcipher_request_set_tfm(&req, ctr);
- ablkcipher_request_set_crypt(&req, &sg, &sg, 16, counterblock);
- ablkcipher_request_set_callback(&req, 0, NULL, NULL);
- memset(block, 0, 16);
- return crypto_ablkcipher_encrypt(&req);
+ if (err == -EINPROGRESS)
+ return;
+
+ result->err = err;
+ complete(&result->completion);
}
static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key,
@@ -192,10 +181,16 @@ static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key,
{
struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
struct crypto_ablkcipher *ctr = ctx->ctr;
- int alignmask = crypto_ablkcipher_alignmask(ctr);
- u8 alignbuf[16+alignmask];
- u8 *hash = (u8 *)ALIGN((unsigned long)alignbuf, alignmask+1);
- int err = 0;
+ 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) &
@@ -203,62 +198,86 @@ static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key,
err = crypto_ablkcipher_setkey(ctr, key, keylen);
if (err)
- goto out;
+ return err;
crypto_aead_set_flags(aead, crypto_ablkcipher_get_flags(ctr) &
CRYPTO_TFM_RES_MASK);
- err = crypto_gcm_encrypt_counter(aead, hash, -1, NULL);
+ 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;
if (ctx->gf128 != NULL)
gf128mul_free_4k(ctx->gf128);
- ctx->gf128 = gf128mul_init_4k_lle((be128 *)hash);
+ ctx->gf128 = gf128mul_init_4k_lle(&data->hash);
if (ctx->gf128 == NULL)
err = -ENOMEM;
- out:
+out:
+ kfree(data);
return err;
}
-static int crypto_gcm_init_crypt(struct ablkcipher_request *ablk_req,
- struct aead_request *req,
- unsigned int cryptlen,
- void (*done)(struct crypto_async_request *,
- int))
+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);
u32 flags = req->base.tfm->crt_flags;
- u8 *auth_tag = pctx->auth_tag;
- u8 *counter = pctx->counter;
struct crypto_gcm_ghash_ctx *ghash = &pctx->ghash;
- int err = 0;
+ 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_callback(ablk_req, aead_request_flags(req),
- done, req);
- ablkcipher_request_set_crypt(ablk_req, req->src, req->dst,
- cryptlen, counter);
-
- err = crypto_gcm_encrypt_counter(aead, auth_tag, 0, req->iv);
- if (err)
- goto out;
-
- memcpy(counter, req->iv, 12);
- crypto_gcm_set_counter(counter, 1);
+ ablkcipher_request_set_crypt(ablk_req, pctx->src, dst,
+ cryptlen + sizeof(pctx->auth_tag),
+ req->iv);
crypto_gcm_ghash_init(ghash, flags, ctx->gf128);
crypto_gcm_ghash_update_sg(ghash, req->assoc, req->assoclen);
crypto_gcm_ghash_flush(ghash);
-
- out:
- return err;
}
static int crypto_gcm_hash(struct aead_request *req)
@@ -291,25 +310,44 @@ 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->abreq;
- int err = 0;
+ int err;
+
+ crypto_gcm_init_crypt(abreq, req, req->cryptlen);
+ ablkcipher_request_set_callback(abreq, aead_request_flags(req),
+ crypto_gcm_encrypt_done, req);
- err = crypto_gcm_init_crypt(abreq, req, req->cryptlen,
- crypto_gcm_encrypt_done);
+ err = crypto_ablkcipher_encrypt(abreq);
if (err)
return err;
- if (req->cryptlen) {
- err = crypto_ablkcipher_encrypt(abreq);
- if (err)
- return err;
- }
-
return crypto_gcm_hash(req);
}
+static int crypto_gcm_verify(struct aead_request *req)
+{
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
+ struct crypto_gcm_ghash_ctx *ghash = &pctx->ghash;
+ 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_gcm_ghash_final_xor(ghash, req->assoclen, cryptlen, auth_tag);
+
+ authsize = crypto_aead_authsize(aead);
+ scatterwalk_map_and_copy(iauth_tag, req->src, cryptlen, authsize, 0);
+ return memcmp(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0;
+}
+
static void crypto_gcm_decrypt_done(struct crypto_async_request *areq, int err)
{
- aead_request_complete(areq->data, err);
+ struct aead_request *req = areq->data;
+
+ if (!err)
+ err = crypto_gcm_verify(req);
+
+ aead_request_complete(req, err);
}
static int crypto_gcm_decrypt(struct aead_request *req)
@@ -317,8 +355,6 @@ 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->abreq;
- u8 *auth_tag = pctx->auth_tag;
- u8 *iauth_tag = pctx->iauth_tag;
struct crypto_gcm_ghash_ctx *ghash = &pctx->ghash;
unsigned int cryptlen = req->cryptlen;
unsigned int authsize = crypto_aead_authsize(aead);
@@ -328,19 +364,17 @@ static int crypto_gcm_decrypt(struct aead_request *req)
return -EINVAL;
cryptlen -= authsize;
- err = crypto_gcm_init_crypt(abreq, req, cryptlen,
- crypto_gcm_decrypt_done);
- if (err)
- return err;
+ crypto_gcm_init_crypt(abreq, req, cryptlen);
+ ablkcipher_request_set_callback(abreq, aead_request_flags(req),
+ crypto_gcm_decrypt_done, req);
crypto_gcm_ghash_update_sg(ghash, req->src, cryptlen);
- crypto_gcm_ghash_final_xor(ghash, req->assoclen, cryptlen, auth_tag);
- scatterwalk_map_and_copy(iauth_tag, req->src, cryptlen, authsize, 0);
- if (memcmp(iauth_tag, auth_tag, authsize))
- return -EBADMSG;
+ err = crypto_ablkcipher_decrypt(abreq);
+ if (err)
+ return err;
- return crypto_ablkcipher_decrypt(abreq);
+ return crypto_gcm_verify(req);
}
static int crypto_gcm_init_tfm(struct crypto_tfm *tfm)
@@ -436,7 +470,7 @@ static struct crypto_instance *crypto_gcm_alloc(struct rtattr **tb)
inst->alg.cra_blocksize = 16;
inst->alg.cra_alignmask = ctr->cra_alignmask | (__alignof__(u64) - 1);
inst->alg.cra_type = &crypto_aead_type;
- inst->alg.cra_aead.ivsize = 12;
+ 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;