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-rw-r--r--crypto/ahash.c615
1 files changed, 615 insertions, 0 deletions
diff --git a/crypto/ahash.c b/crypto/ahash.c
new file mode 100644
index 000000000..8acb88603
--- /dev/null
+++ b/crypto/ahash.c
@@ -0,0 +1,615 @@
+/*
+ * Asynchronous Cryptographic Hash operations.
+ *
+ * This is the asynchronous version of hash.c with notification of
+ * completion via a callback.
+ *
+ * Copyright (c) 2008 Loc Ho <lho@amcc.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ */
+
+#include <crypto/internal/hash.h>
+#include <crypto/scatterwalk.h>
+#include <linux/bug.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/seq_file.h>
+#include <linux/cryptouser.h>
+#include <net/netlink.h>
+
+#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,
+ halg);
+}
+
+static int hash_walk_next(struct crypto_hash_walk *walk)
+{
+ unsigned int alignmask = walk->alignmask;
+ unsigned int offset = walk->offset;
+ unsigned int nbytes = min(walk->entrylen,
+ ((unsigned int)(PAGE_SIZE)) - offset);
+
+ if (walk->flags & CRYPTO_ALG_ASYNC)
+ walk->data = kmap(walk->pg);
+ else
+ walk->data = kmap_atomic(walk->pg);
+ walk->data += offset;
+
+ if (offset & alignmask) {
+ unsigned int unaligned = alignmask + 1 - (offset & alignmask);
+
+ if (nbytes > unaligned)
+ nbytes = unaligned;
+ }
+
+ walk->entrylen -= nbytes;
+ return nbytes;
+}
+
+static int hash_walk_new_entry(struct crypto_hash_walk *walk)
+{
+ struct scatterlist *sg;
+
+ sg = walk->sg;
+ walk->pg = sg_page(sg);
+ walk->offset = sg->offset;
+ walk->entrylen = sg->length;
+
+ if (walk->entrylen > walk->total)
+ walk->entrylen = walk->total;
+ walk->total -= walk->entrylen;
+
+ return hash_walk_next(walk);
+}
+
+int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
+{
+ unsigned int alignmask = walk->alignmask;
+ unsigned int nbytes = walk->entrylen;
+
+ walk->data -= walk->offset;
+
+ if (nbytes && walk->offset & alignmask && !err) {
+ walk->offset = ALIGN(walk->offset, alignmask + 1);
+ walk->data += walk->offset;
+
+ nbytes = min(nbytes,
+ ((unsigned int)(PAGE_SIZE)) - walk->offset);
+ walk->entrylen -= nbytes;
+
+ return nbytes;
+ }
+
+ if (walk->flags & CRYPTO_ALG_ASYNC)
+ kunmap(walk->pg);
+ else {
+ kunmap_atomic(walk->data);
+ /*
+ * The may sleep test only makes sense for sync users.
+ * Async users don't need to sleep here anyway.
+ */
+ crypto_yield(walk->flags);
+ }
+
+ if (err)
+ return err;
+
+ if (nbytes) {
+ walk->offset = 0;
+ walk->pg++;
+ return hash_walk_next(walk);
+ }
+
+ if (!walk->total)
+ return 0;
+
+ walk->sg = sg_next(walk->sg);
+
+ return hash_walk_new_entry(walk);
+}
+EXPORT_SYMBOL_GPL(crypto_hash_walk_done);
+
+int crypto_hash_walk_first(struct ahash_request *req,
+ struct crypto_hash_walk *walk)
+{
+ walk->total = req->nbytes;
+
+ if (!walk->total) {
+ walk->entrylen = 0;
+ return 0;
+ }
+
+ walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
+ walk->sg = req->src;
+ walk->flags = req->base.flags & CRYPTO_TFM_REQ_MASK;
+
+ return hash_walk_new_entry(walk);
+}
+EXPORT_SYMBOL_GPL(crypto_hash_walk_first);
+
+int crypto_ahash_walk_first(struct ahash_request *req,
+ struct crypto_hash_walk *walk)
+{
+ walk->total = req->nbytes;
+
+ if (!walk->total) {
+ walk->entrylen = 0;
+ return 0;
+ }
+
+ walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
+ walk->sg = req->src;
+ walk->flags = req->base.flags & CRYPTO_TFM_REQ_MASK;
+ walk->flags |= CRYPTO_ALG_ASYNC;
+
+ BUILD_BUG_ON(CRYPTO_TFM_REQ_MASK & CRYPTO_ALG_ASYNC);
+
+ return hash_walk_new_entry(walk);
+}
+EXPORT_SYMBOL_GPL(crypto_ahash_walk_first);
+
+int crypto_hash_walk_first_compat(struct hash_desc *hdesc,
+ struct crypto_hash_walk *walk,
+ struct scatterlist *sg, unsigned int len)
+{
+ walk->total = len;
+
+ if (!walk->total) {
+ walk->entrylen = 0;
+ return 0;
+ }
+
+ walk->alignmask = crypto_hash_alignmask(hdesc->tfm);
+ walk->sg = sg;
+ walk->flags = hdesc->flags & CRYPTO_TFM_REQ_MASK;
+
+ return hash_walk_new_entry(walk);
+}
+
+static int ahash_setkey_unaligned(struct crypto_ahash *tfm, const u8 *key,
+ unsigned int keylen)
+{
+ unsigned long alignmask = crypto_ahash_alignmask(tfm);
+ int ret;
+ u8 *buffer, *alignbuffer;
+ unsigned long absize;
+
+ absize = keylen + alignmask;
+ buffer = kmalloc(absize, GFP_KERNEL);
+ if (!buffer)
+ return -ENOMEM;
+
+ alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
+ memcpy(alignbuffer, key, keylen);
+ ret = tfm->setkey(tfm, alignbuffer, keylen);
+ kzfree(buffer);
+ return ret;
+}
+
+int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
+ unsigned int keylen)
+{
+ unsigned long alignmask = crypto_ahash_alignmask(tfm);
+
+ if ((unsigned long)key & alignmask)
+ return ahash_setkey_unaligned(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)
+{
+ return -ENOSYS;
+}
+
+static inline unsigned int ahash_align_buffer_size(unsigned len,
+ unsigned long mask)
+{
+ return len + (mask & ~(crypto_tfm_ctx_alignment() - 1));
+}
+
+static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt)
+{
+ 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;
+
+ /*
+ * WARNING: Voodoo programming below!
+ *
+ * The code below is obscure and hard to understand, thus explanation
+ * is necessary. See include/crypto/hash.h and include/linux/crypto.h
+ * to understand the layout of structures used here!
+ *
+ * The code here will replace portions of the ORIGINAL request with
+ * pointers to new code and buffers so the hashing operation can store
+ * the result in aligned buffer. We will call the modified request
+ * an ADJUSTED request.
+ *
+ * The newly mangled request will look as such:
+ *
+ * req {
+ * .result = ADJUSTED[new aligned buffer]
+ * .base.complete = ADJUSTED[pointer to completion function]
+ * .base.data = ADJUSTED[*req (pointer to self)]
+ * .priv = ADJUSTED[new priv] {
+ * .result = ORIGINAL(result)
+ * .complete = ORIGINAL(base.complete)
+ * .data = ORIGINAL(base.data)
+ * }
+ */
+
+ priv->result = req->result;
+ priv->complete = req->base.complete;
+ priv->data = req->base.data;
+ /*
+ * WARNING: We do not backup req->priv here! The req->priv
+ * is for internal use of the Crypto API and the
+ * user must _NOT_ _EVER_ depend on it's content!
+ */
+
+ req->result = PTR_ALIGN((u8 *)priv->ubuf, alignmask + 1);
+ req->base.complete = cplt;
+ req->base.data = req;
+ req->priv = priv;
+
+ return 0;
+}
+
+static void ahash_restore_req(struct ahash_request *req)
+{
+ struct ahash_request_priv *priv = req->priv;
+
+ /* Restore the original crypto request. */
+ req->result = priv->result;
+ req->base.complete = priv->complete;
+ req->base.data = priv->data;
+ req->priv = NULL;
+
+ /* Free the req->priv.priv from the ADJUSTED request. */
+ kzfree(priv);
+}
+
+static void ahash_op_unaligned_finish(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)));
+
+ ahash_restore_req(req);
+}
+
+static void ahash_op_unaligned_done(struct crypto_async_request *req, int err)
+{
+ struct ahash_request *areq = req->data;
+
+ /*
+ * Restore the original request, see ahash_op_unaligned() for what
+ * goes where.
+ *
+ * The "struct ahash_request *req" here is in fact the "req.base"
+ * from the ADJUSTED request from ahash_op_unaligned(), thus as it
+ * is a pointer to self, it is also the ADJUSTED "req" .
+ */
+
+ /* First copy req->result into req->priv.result */
+ ahash_op_unaligned_finish(areq, err);
+
+ /* Complete the ORIGINAL request. */
+ areq->base.complete(&areq->base, err);
+}
+
+static int ahash_op_unaligned(struct ahash_request *req,
+ int (*op)(struct ahash_request *))
+{
+ int err;
+
+ err = ahash_save_req(req, ahash_op_unaligned_done);
+ if (err)
+ return err;
+
+ 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)));
+
+ ahash_restore_req(req);
+}
+
+static void ahash_def_finup_done2(struct crypto_async_request *req, int err)
+{
+ struct ahash_request *areq = req->data;
+
+ ahash_def_finup_finish2(areq, err);
+
+ areq->base.complete(&areq->base, 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;
+
+ err = ahash_def_finup_finish1(areq, err);
+
+ areq->base.complete(&areq->base, err);
+}
+
+static int ahash_def_finup(struct ahash_request *req)
+{
+ struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+ int err;
+
+ err = ahash_save_req(req, ahash_def_finup_done1);
+ if (err)
+ return err;
+
+ err = tfm->update(req);
+ return ahash_def_finup_finish1(req, err);
+}
+
+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);
+
+ 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);
+
+ hash->init = alg->init;
+ hash->update = alg->update;
+ hash->final = alg->final;
+ hash->finup = alg->finup ?: ahash_def_finup;
+ hash->digest = alg->digest;
+
+ if (alg->setkey)
+ hash->setkey = alg->setkey;
+ if (alg->export)
+ hash->export = alg->export;
+ if (alg->import)
+ hash->import = alg->import;
+
+ return 0;
+}
+
+static unsigned int crypto_ahash_extsize(struct crypto_alg *alg)
+{
+ if (alg->cra_type == &crypto_ahash_type)
+ return alg->cra_ctxsize;
+
+ return sizeof(struct crypto_shash *);
+}
+
+#ifdef CONFIG_NET
+static int crypto_ahash_report(struct sk_buff *skb, struct crypto_alg *alg)
+{
+ struct crypto_report_hash rhash;
+
+ strncpy(rhash.type, "ahash", sizeof(rhash.type));
+
+ rhash.blocksize = alg->cra_blocksize;
+ rhash.digestsize = __crypto_hash_alg_common(alg)->digestsize;
+
+ if (nla_put(skb, CRYPTOCFGA_REPORT_HASH,
+ sizeof(struct crypto_report_hash), &rhash))
+ goto nla_put_failure;
+ return 0;
+
+nla_put_failure:
+ return -EMSGSIZE;
+}
+#else
+static int crypto_ahash_report(struct sk_buff *skb, struct crypto_alg *alg)
+{
+ return -ENOSYS;
+}
+#endif
+
+static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
+ __attribute__ ((unused));
+static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
+{
+ seq_printf(m, "type : ahash\n");
+ seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
+ "yes" : "no");
+ seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
+ seq_printf(m, "digestsize : %u\n",
+ __crypto_hash_alg_common(alg)->digestsize);
+}
+
+const struct crypto_type crypto_ahash_type = {
+ .extsize = crypto_ahash_extsize,
+ .init_tfm = crypto_ahash_init_tfm,
+#ifdef CONFIG_PROC_FS
+ .show = crypto_ahash_show,
+#endif
+ .report = crypto_ahash_report,
+ .maskclear = ~CRYPTO_ALG_TYPE_MASK,
+ .maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
+ .type = CRYPTO_ALG_TYPE_AHASH,
+ .tfmsize = offsetof(struct crypto_ahash, base),
+};
+EXPORT_SYMBOL_GPL(crypto_ahash_type);
+
+struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
+ u32 mask)
+{
+ return crypto_alloc_tfm(alg_name, &crypto_ahash_type, type, mask);
+}
+EXPORT_SYMBOL_GPL(crypto_alloc_ahash);
+
+static int ahash_prepare_alg(struct ahash_alg *alg)
+{
+ struct crypto_alg *base = &alg->halg.base;
+
+ if (alg->halg.digestsize > PAGE_SIZE / 8 ||
+ alg->halg.statesize > PAGE_SIZE / 8)
+ return -EINVAL;
+
+ base->cra_type = &crypto_ahash_type;
+ base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
+ base->cra_flags |= CRYPTO_ALG_TYPE_AHASH;
+
+ return 0;
+}
+
+int crypto_register_ahash(struct ahash_alg *alg)
+{
+ struct crypto_alg *base = &alg->halg.base;
+ int err;
+
+ err = ahash_prepare_alg(alg);
+ if (err)
+ return err;
+
+ return crypto_register_alg(base);
+}
+EXPORT_SYMBOL_GPL(crypto_register_ahash);
+
+int crypto_unregister_ahash(struct ahash_alg *alg)
+{
+ return crypto_unregister_alg(&alg->halg.base);
+}
+EXPORT_SYMBOL_GPL(crypto_unregister_ahash);
+
+int ahash_register_instance(struct crypto_template *tmpl,
+ struct ahash_instance *inst)
+{
+ int err;
+
+ err = ahash_prepare_alg(&inst->alg);
+ if (err)
+ return err;
+
+ return crypto_register_instance(tmpl, ahash_crypto_instance(inst));
+}
+EXPORT_SYMBOL_GPL(ahash_register_instance);
+
+void ahash_free_instance(struct crypto_instance *inst)
+{
+ crypto_drop_spawn(crypto_instance_ctx(inst));
+ kfree(ahash_instance(inst));
+}
+EXPORT_SYMBOL_GPL(ahash_free_instance);
+
+int crypto_init_ahash_spawn(struct crypto_ahash_spawn *spawn,
+ struct hash_alg_common *alg,
+ struct crypto_instance *inst)
+{
+ return crypto_init_spawn2(&spawn->base, &alg->base, inst,
+ &crypto_ahash_type);
+}
+EXPORT_SYMBOL_GPL(crypto_init_ahash_spawn);
+
+struct hash_alg_common *ahash_attr_alg(struct rtattr *rta, u32 type, u32 mask)
+{
+ struct crypto_alg *alg;
+
+ alg = crypto_attr_alg2(rta, &crypto_ahash_type, type, mask);
+ return IS_ERR(alg) ? ERR_CAST(alg) : __crypto_hash_alg_common(alg);
+}
+EXPORT_SYMBOL_GPL(ahash_attr_alg);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Asynchronous cryptographic hash type");