crypto: tcrypt - do not attempt to write to readonly variable
[linux-2.6.git] / crypto / ahash.c
index 7f599d2..f669822 100644 (file)
 
 #include "internal.h"
 
+struct ahash_request_priv {
+       crypto_completion_t complete;
+       void *data;
+       u8 *result;
+       void *ubuf[] CRYPTO_MINALIGN_ATTR;
+};
+
 static inline struct ahash_alg *crypto_ahash_alg(struct crypto_ahash *hash)
 {
        return container_of(crypto_hash_alg_common(hash), struct ahash_alg,
@@ -40,8 +47,11 @@ static int hash_walk_next(struct crypto_hash_walk *walk)
        walk->data = crypto_kmap(walk->pg, 0);
        walk->data += offset;
 
-       if (offset & alignmask)
-               nbytes = alignmask + 1 - (offset & alignmask);
+       if (offset & alignmask) {
+               unsigned int unaligned = alignmask + 1 - (offset & alignmask);
+               if (nbytes > unaligned)
+                       nbytes = unaligned;
+       }
 
        walk->entrylen -= nbytes;
        return nbytes;
@@ -71,7 +81,6 @@ int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
        walk->data -= walk->offset;
 
        if (nbytes && walk->offset & alignmask && !err) {
-               walk->offset += alignmask - 1;
                walk->offset = ALIGN(walk->offset, alignmask + 1);
                walk->data += walk->offset;
 
@@ -138,36 +147,34 @@ int crypto_hash_walk_first_compat(struct hash_desc *hdesc,
 static int ahash_setkey_unaligned(struct crypto_ahash *tfm, const u8 *key,
                                unsigned int keylen)
 {
-       struct ahash_alg *ahash = crypto_ahash_alg(tfm);
        unsigned long alignmask = crypto_ahash_alignmask(tfm);
        int ret;
        u8 *buffer, *alignbuffer;
        unsigned long absize;
 
        absize = keylen + alignmask;
-       buffer = kmalloc(absize, GFP_ATOMIC);
+       buffer = kmalloc(absize, GFP_KERNEL);
        if (!buffer)
                return -ENOMEM;
 
        alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
        memcpy(alignbuffer, key, keylen);
-       ret = ahash->setkey(tfm, alignbuffer, keylen);
-       memset(alignbuffer, 0, keylen);
-       kfree(buffer);
+       ret = tfm->setkey(tfm, alignbuffer, keylen);
+       kzfree(buffer);
        return ret;
 }
 
-static int ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
+int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
                        unsigned int keylen)
 {
-       struct ahash_alg *ahash = crypto_ahash_alg(tfm);
        unsigned long alignmask = crypto_ahash_alignmask(tfm);
 
        if ((unsigned long)key & alignmask)
                return ahash_setkey_unaligned(tfm, key, keylen);
 
-       return ahash->setkey(tfm, key, keylen);
+       return tfm->setkey(tfm, key, keylen);
 }
+EXPORT_SYMBOL_GPL(crypto_ahash_setkey);
 
 static int ahash_nosetkey(struct crypto_ahash *tfm, const u8 *key,
                          unsigned int keylen)
@@ -175,46 +182,209 @@ static int ahash_nosetkey(struct crypto_ahash *tfm, const u8 *key,
        return -ENOSYS;
 }
 
-static int crypto_init_ahash_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
+static inline unsigned int ahash_align_buffer_size(unsigned len,
+                                                  unsigned long mask)
 {
-       struct old_ahash_alg *alg = &tfm->__crt_alg->cra_ahash;
-       struct crypto_ahash *crt = __crypto_ahash_cast(tfm);
-       struct ahash_alg *nalg = crypto_ahash_alg(crt);
+       return len + (mask & ~(crypto_tfm_ctx_alignment() - 1));
+}
 
-       if (alg->digestsize > PAGE_SIZE / 8)
-               return -EINVAL;
+static void ahash_op_unaligned_finish(struct ahash_request *req, int err)
+{
+       struct ahash_request_priv *priv = req->priv;
 
-       crt->init = alg->init;
-       crt->update = alg->update;
-       crt->final  = alg->final;
-       crt->digest = alg->digest;
-       crt->setkey = alg->setkey ? ahash_setkey : ahash_nosetkey;
-       crt->digestsize = alg->digestsize;
+       if (err == -EINPROGRESS)
+               return;
 
-       nalg->setkey = alg->setkey;
-       nalg->halg.digestsize = alg->digestsize;
+       if (!err)
+               memcpy(priv->result, req->result,
+                      crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
 
-       return 0;
+       kzfree(priv);
+}
+
+static void ahash_op_unaligned_done(struct crypto_async_request *req, int err)
+{
+       struct ahash_request *areq = req->data;
+       struct ahash_request_priv *priv = areq->priv;
+       crypto_completion_t complete = priv->complete;
+       void *data = priv->data;
+
+       ahash_op_unaligned_finish(areq, err);
+
+       complete(data, err);
+}
+
+static int ahash_op_unaligned(struct ahash_request *req,
+                             int (*op)(struct ahash_request *))
+{
+       struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+       unsigned long alignmask = crypto_ahash_alignmask(tfm);
+       unsigned int ds = crypto_ahash_digestsize(tfm);
+       struct ahash_request_priv *priv;
+       int err;
+
+       priv = kmalloc(sizeof(*priv) + ahash_align_buffer_size(ds, alignmask),
+                      (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
+                      GFP_KERNEL : GFP_ATOMIC);
+       if (!priv)
+               return -ENOMEM;
+
+       priv->result = req->result;
+       priv->complete = req->base.complete;
+       priv->data = req->base.data;
+
+       req->result = PTR_ALIGN((u8 *)priv->ubuf, alignmask + 1);
+       req->base.complete = ahash_op_unaligned_done;
+       req->base.data = req;
+       req->priv = priv;
+
+       err = op(req);
+       ahash_op_unaligned_finish(req, err);
+
+       return err;
+}
+
+static int crypto_ahash_op(struct ahash_request *req,
+                          int (*op)(struct ahash_request *))
+{
+       struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+       unsigned long alignmask = crypto_ahash_alignmask(tfm);
+
+       if ((unsigned long)req->result & alignmask)
+               return ahash_op_unaligned(req, op);
+
+       return op(req);
+}
+
+int crypto_ahash_final(struct ahash_request *req)
+{
+       return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->final);
+}
+EXPORT_SYMBOL_GPL(crypto_ahash_final);
+
+int crypto_ahash_finup(struct ahash_request *req)
+{
+       return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->finup);
+}
+EXPORT_SYMBOL_GPL(crypto_ahash_finup);
+
+int crypto_ahash_digest(struct ahash_request *req)
+{
+       return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->digest);
+}
+EXPORT_SYMBOL_GPL(crypto_ahash_digest);
+
+static void ahash_def_finup_finish2(struct ahash_request *req, int err)
+{
+       struct ahash_request_priv *priv = req->priv;
+
+       if (err == -EINPROGRESS)
+               return;
+
+       if (!err)
+               memcpy(priv->result, req->result,
+                      crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
+
+       kzfree(priv);
+}
+
+static void ahash_def_finup_done2(struct crypto_async_request *req, int err)
+{
+       struct ahash_request *areq = req->data;
+       struct ahash_request_priv *priv = areq->priv;
+       crypto_completion_t complete = priv->complete;
+       void *data = priv->data;
+
+       ahash_def_finup_finish2(areq, err);
+
+       complete(data, err);
+}
+
+static int ahash_def_finup_finish1(struct ahash_request *req, int err)
+{
+       if (err)
+               goto out;
+
+       req->base.complete = ahash_def_finup_done2;
+       req->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
+       err = crypto_ahash_reqtfm(req)->final(req);
+
+out:
+       ahash_def_finup_finish2(req, err);
+       return err;
+}
+
+static void ahash_def_finup_done1(struct crypto_async_request *req, int err)
+{
+       struct ahash_request *areq = req->data;
+       struct ahash_request_priv *priv = areq->priv;
+       crypto_completion_t complete = priv->complete;
+       void *data = priv->data;
+
+       err = ahash_def_finup_finish1(areq, err);
+
+       complete(data, err);
+}
+
+static int ahash_def_finup(struct ahash_request *req)
+{
+       struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+       unsigned long alignmask = crypto_ahash_alignmask(tfm);
+       unsigned int ds = crypto_ahash_digestsize(tfm);
+       struct ahash_request_priv *priv;
+
+       priv = kmalloc(sizeof(*priv) + ahash_align_buffer_size(ds, alignmask),
+                      (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
+                      GFP_KERNEL : GFP_ATOMIC);
+       if (!priv)
+               return -ENOMEM;
+
+       priv->result = req->result;
+       priv->complete = req->base.complete;
+       priv->data = req->base.data;
+
+       req->result = PTR_ALIGN((u8 *)priv->ubuf, alignmask + 1);
+       req->base.complete = ahash_def_finup_done1;
+       req->base.data = req;
+       req->priv = priv;
+
+       return ahash_def_finup_finish1(req, tfm->update(req));
+}
+
+static int ahash_no_export(struct ahash_request *req, void *out)
+{
+       return -ENOSYS;
+}
+
+static int ahash_no_import(struct ahash_request *req, const void *in)
+{
+       return -ENOSYS;
 }
 
 static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
 {
        struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
        struct ahash_alg *alg = crypto_ahash_alg(hash);
-       struct old_ahash_alg *oalg = crypto_old_ahash_alg(hash);
+
+       hash->setkey = ahash_nosetkey;
+       hash->export = ahash_no_export;
+       hash->import = ahash_no_import;
 
        if (tfm->__crt_alg->cra_type != &crypto_ahash_type)
                return crypto_init_shash_ops_async(tfm);
 
-       if (oalg->init)
-               return crypto_init_ahash_ops(tfm, 0, 0);
-
        hash->init = alg->init;
        hash->update = alg->update;
-       hash->final  = alg->final;
+       hash->final = alg->final;
+       hash->finup = alg->finup ?: ahash_def_finup;
        hash->digest = alg->digest;
-       hash->setkey = alg->setkey ? ahash_setkey : ahash_nosetkey;
-       hash->digestsize = alg->halg.digestsize;
+
+       if (alg->setkey)
+               hash->setkey = alg->setkey;
+       if (alg->export)
+               hash->export = alg->export;
+       if (alg->import)
+               hash->import = alg->import;
 
        return 0;
 }