1 files changed, 112 insertions, 78 deletions

diff --git a/crypto/gcm.c b/crypto/gcm.c
index c54d478948a0..f6bee6f209a6 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;