Initial import

1 files changed, 615 insertions, 0 deletions

diff --git a/crypto/api.c b/crypto/api.c
new file mode 100644
index 000000000..afe4610af
--- /dev/null
+++ b/crypto/api.c
@@ -0,0 +1,615 @@
+/*
+ * Scatterlist Cryptographic API.
+ *
+ * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
+ * Copyright (c) 2002 David S. Miller (davem@redhat.com)
+ * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
+ *
+ * Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
+ * and Nettle, by Niels Möller.
+ *
+ * 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 <linux/err.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/kmod.h>
+#include <linux/module.h>
+#include <linux/param.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include "internal.h"
+
+LIST_HEAD(crypto_alg_list);
+EXPORT_SYMBOL_GPL(crypto_alg_list);
+DECLARE_RWSEM(crypto_alg_sem);
+EXPORT_SYMBOL_GPL(crypto_alg_sem);
+
+BLOCKING_NOTIFIER_HEAD(crypto_chain);
+EXPORT_SYMBOL_GPL(crypto_chain);
+
+static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg);
+
+struct crypto_alg *crypto_mod_get(struct crypto_alg *alg)
+{
+	return try_module_get(alg->cra_module) ? crypto_alg_get(alg) : NULL;
+}
+EXPORT_SYMBOL_GPL(crypto_mod_get);
+
+void crypto_mod_put(struct crypto_alg *alg)
+{
+	struct module *module = alg->cra_module;
+
+	crypto_alg_put(alg);
+	module_put(module);
+}
+EXPORT_SYMBOL_GPL(crypto_mod_put);
+
+static inline int crypto_is_test_larval(struct crypto_larval *larval)
+{
+	return larval->alg.cra_driver_name[0];
+}
+
+static struct crypto_alg *__crypto_alg_lookup(const char *name, u32 type,
+					      u32 mask)
+{
+	struct crypto_alg *q, *alg = NULL;
+	int best = -2;
+
+	list_for_each_entry(q, &crypto_alg_list, cra_list) {
+		int exact, fuzzy;
+
+		if (crypto_is_moribund(q))
+			continue;
+
+		if ((q->cra_flags ^ type) & mask)
+			continue;
+
+		if (crypto_is_larval(q) &&
+		    !crypto_is_test_larval((struct crypto_larval *)q) &&
+		    ((struct crypto_larval *)q)->mask != mask)
+			continue;
+
+		exact = !strcmp(q->cra_driver_name, name);
+		fuzzy = !strcmp(q->cra_name, name);
+		if (!exact && !(fuzzy && q->cra_priority > best))
+			continue;
+
+		if (unlikely(!crypto_mod_get(q)))
+			continue;
+
+		best = q->cra_priority;
+		if (alg)
+			crypto_mod_put(alg);
+		alg = q;
+
+		if (exact)
+			break;
+	}
+
+	return alg;
+}
+
+static void crypto_larval_destroy(struct crypto_alg *alg)
+{
+	struct crypto_larval *larval = (void *)alg;
+
+	BUG_ON(!crypto_is_larval(alg));
+	if (larval->adult)
+		crypto_mod_put(larval->adult);
+	kfree(larval);
+}
+
+struct crypto_larval *crypto_larval_alloc(const char *name, u32 type, u32 mask)
+{
+	struct crypto_larval *larval;
+
+	larval = kzalloc(sizeof(*larval), GFP_KERNEL);
+	if (!larval)
+		return ERR_PTR(-ENOMEM);
+
+	larval->mask = mask;
+	larval->alg.cra_flags = CRYPTO_ALG_LARVAL | type;
+	larval->alg.cra_priority = -1;
+	larval->alg.cra_destroy = crypto_larval_destroy;
+
+	strlcpy(larval->alg.cra_name, name, CRYPTO_MAX_ALG_NAME);
+	init_completion(&larval->completion);
+
+	return larval;
+}
+EXPORT_SYMBOL_GPL(crypto_larval_alloc);
+
+static struct crypto_alg *crypto_larval_add(const char *name, u32 type,
+					    u32 mask)
+{
+	struct crypto_alg *alg;
+	struct crypto_larval *larval;
+
+	larval = crypto_larval_alloc(name, type, mask);
+	if (IS_ERR(larval))
+		return ERR_CAST(larval);
+
+	atomic_set(&larval->alg.cra_refcnt, 2);
+
+	down_write(&crypto_alg_sem);
+	alg = __crypto_alg_lookup(name, type, mask);
+	if (!alg) {
+		alg = &larval->alg;
+		list_add(&alg->cra_list, &crypto_alg_list);
+	}
+	up_write(&crypto_alg_sem);
+
+	if (alg != &larval->alg) {
+		kfree(larval);
+		if (crypto_is_larval(alg))
+			alg = crypto_larval_wait(alg);
+	}
+
+	return alg;
+}
+
+void crypto_larval_kill(struct crypto_alg *alg)
+{
+	struct crypto_larval *larval = (void *)alg;
+
+	down_write(&crypto_alg_sem);
+	list_del(&alg->cra_list);
+	up_write(&crypto_alg_sem);
+	complete_all(&larval->completion);
+	crypto_alg_put(alg);
+}
+EXPORT_SYMBOL_GPL(crypto_larval_kill);
+
+static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg)
+{
+	struct crypto_larval *larval = (void *)alg;
+	long timeout;
+
+	timeout = wait_for_completion_interruptible_timeout(
+		&larval->completion, 60 * HZ);
+
+	alg = larval->adult;
+	if (timeout < 0)
+		alg = ERR_PTR(-EINTR);
+	else if (!timeout)
+		alg = ERR_PTR(-ETIMEDOUT);
+	else if (!alg)
+		alg = ERR_PTR(-ENOENT);
+	else if (crypto_is_test_larval(larval) &&
+		 !(alg->cra_flags & CRYPTO_ALG_TESTED))
+		alg = ERR_PTR(-EAGAIN);
+	else if (!crypto_mod_get(alg))
+		alg = ERR_PTR(-EAGAIN);
+	crypto_mod_put(&larval->alg);
+
+	return alg;
+}
+
+struct crypto_alg *crypto_alg_lookup(const char *name, u32 type, u32 mask)
+{
+	struct crypto_alg *alg;
+
+	down_read(&crypto_alg_sem);
+	alg = __crypto_alg_lookup(name, type, mask);
+	up_read(&crypto_alg_sem);
+
+	return alg;
+}
+EXPORT_SYMBOL_GPL(crypto_alg_lookup);
+
+struct crypto_alg *crypto_larval_lookup(const char *name, u32 type, u32 mask)
+{
+	struct crypto_alg *alg;
+
+	if (!name)
+		return ERR_PTR(-ENOENT);
+
+	mask &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
+	type &= mask;
+
+	alg = crypto_alg_lookup(name, type, mask);
+	if (!alg) {
+		request_module("crypto-%s", name);
+
+		if (!((type ^ CRYPTO_ALG_NEED_FALLBACK) & mask &
+		      CRYPTO_ALG_NEED_FALLBACK))
+			request_module("crypto-%s-all", name);
+
+		alg = crypto_alg_lookup(name, type, mask);
+	}
+
+	if (alg)
+		return crypto_is_larval(alg) ? crypto_larval_wait(alg) : alg;
+
+	return crypto_larval_add(name, type, mask);
+}
+EXPORT_SYMBOL_GPL(crypto_larval_lookup);
+
+int crypto_probing_notify(unsigned long val, void *v)
+{
+	int ok;
+
+	ok = blocking_notifier_call_chain(&crypto_chain, val, v);
+	if (ok == NOTIFY_DONE) {
+		request_module("cryptomgr");
+		ok = blocking_notifier_call_chain(&crypto_chain, val, v);
+	}
+
+	return ok;
+}
+EXPORT_SYMBOL_GPL(crypto_probing_notify);
+
+struct crypto_alg *crypto_alg_mod_lookup(const char *name, u32 type, u32 mask)
+{
+	struct crypto_alg *alg;
+	struct crypto_alg *larval;
+	int ok;
+
+	if (!((type | mask) & CRYPTO_ALG_TESTED)) {
+		type |= CRYPTO_ALG_TESTED;
+		mask |= CRYPTO_ALG_TESTED;
+	}
+
+	/*
+	 * If the internal flag is set for a cipher, require a caller to
+	 * to invoke the cipher with the internal flag to use that cipher.
+	 * Also, if a caller wants to allocate a cipher that may or may
+	 * not be an internal cipher, use type | CRYPTO_ALG_INTERNAL and
+	 * !(mask & CRYPTO_ALG_INTERNAL).
+	 */
+	if (!((type | mask) & CRYPTO_ALG_INTERNAL))
+		mask |= CRYPTO_ALG_INTERNAL;
+
+	larval = crypto_larval_lookup(name, type, mask);
+	if (IS_ERR(larval) || !crypto_is_larval(larval))
+		return larval;
+
+	ok = crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST, larval);
+
+	if (ok == NOTIFY_STOP)
+		alg = crypto_larval_wait(larval);
+	else {
+		crypto_mod_put(larval);
+		alg = ERR_PTR(-ENOENT);
+	}
+	crypto_larval_kill(larval);
+	return alg;
+}
+EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup);
+
+static int crypto_init_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
+{
+	const struct crypto_type *type_obj = tfm->__crt_alg->cra_type;
+
+	if (type_obj)
+		return type_obj->init(tfm, type, mask);
+
+	switch (crypto_tfm_alg_type(tfm)) {
+	case CRYPTO_ALG_TYPE_CIPHER:
+		return crypto_init_cipher_ops(tfm);
+
+	case CRYPTO_ALG_TYPE_COMPRESS:
+		return crypto_init_compress_ops(tfm);
+
+	default:
+		break;
+	}
+
+	BUG();
+	return -EINVAL;
+}
+
+static void crypto_exit_ops(struct crypto_tfm *tfm)
+{
+	const struct crypto_type *type = tfm->__crt_alg->cra_type;
+
+	if (type) {
+		if (tfm->exit)
+			tfm->exit(tfm);
+		return;
+	}
+
+	switch (crypto_tfm_alg_type(tfm)) {
+	case CRYPTO_ALG_TYPE_CIPHER:
+		crypto_exit_cipher_ops(tfm);
+		break;
+
+	case CRYPTO_ALG_TYPE_COMPRESS:
+		crypto_exit_compress_ops(tfm);
+		break;
+
+	default:
+		BUG();
+	}
+}
+
+static unsigned int crypto_ctxsize(struct crypto_alg *alg, u32 type, u32 mask)
+{
+	const struct crypto_type *type_obj = alg->cra_type;
+	unsigned int len;
+
+	len = alg->cra_alignmask & ~(crypto_tfm_ctx_alignment() - 1);
+	if (type_obj)
+		return len + type_obj->ctxsize(alg, type, mask);
+
+	switch (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) {
+	default:
+		BUG();
+
+	case CRYPTO_ALG_TYPE_CIPHER:
+		len += crypto_cipher_ctxsize(alg);
+		break;
+
+	case CRYPTO_ALG_TYPE_COMPRESS:
+		len += crypto_compress_ctxsize(alg);
+		break;
+	}
+
+	return len;
+}
+
+void crypto_shoot_alg(struct crypto_alg *alg)
+{
+	down_write(&crypto_alg_sem);
+	alg->cra_flags |= CRYPTO_ALG_DYING;
+	up_write(&crypto_alg_sem);
+}
+EXPORT_SYMBOL_GPL(crypto_shoot_alg);
+
+struct crypto_tfm *__crypto_alloc_tfm(struct crypto_alg *alg, u32 type,
+				      u32 mask)
+{
+	struct crypto_tfm *tfm = NULL;
+	unsigned int tfm_size;
+	int err = -ENOMEM;
+
+	tfm_size = sizeof(*tfm) + crypto_ctxsize(alg, type, mask);
+	tfm = kzalloc(tfm_size, GFP_KERNEL);
+	if (tfm == NULL)
+		goto out_err;
+
+	tfm->__crt_alg = alg;
+
+	err = crypto_init_ops(tfm, type, mask);
+	if (err)
+		goto out_free_tfm;
+
+	if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
+		goto cra_init_failed;
+
+	goto out;
+
+cra_init_failed:
+	crypto_exit_ops(tfm);
+out_free_tfm:
+	if (err == -EAGAIN)
+		crypto_shoot_alg(alg);
+	kfree(tfm);
+out_err:
+	tfm = ERR_PTR(err);
+out:
+	return tfm;
+}
+EXPORT_SYMBOL_GPL(__crypto_alloc_tfm);
+
+/*
+ *	crypto_alloc_base - Locate algorithm and allocate transform
+ *	@alg_name: Name of algorithm
+ *	@type: Type of algorithm
+ *	@mask: Mask for type comparison
+ *
+ *	This function should not be used by new algorithm types.
+ *	Please use crypto_alloc_tfm instead.
+ *
+ *	crypto_alloc_base() will first attempt to locate an already loaded
+ *	algorithm.  If that fails and the kernel supports dynamically loadable
+ *	modules, it will then attempt to load a module of the same name or
+ *	alias.  If that fails it will send a query to any loaded crypto manager
+ *	to construct an algorithm on the fly.  A refcount is grabbed on the
+ *	algorithm which is then associated with the new transform.
+ *
+ *	The returned transform is of a non-determinate type.  Most people
+ *	should use one of the more specific allocation functions such as
+ *	crypto_alloc_blkcipher.
+ *
+ *	In case of error the return value is an error pointer.
+ */
+struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask)
+{
+	struct crypto_tfm *tfm;
+	int err;
+
+	for (;;) {
+		struct crypto_alg *alg;
+
+		alg = crypto_alg_mod_lookup(alg_name, type, mask);
+		if (IS_ERR(alg)) {
+			err = PTR_ERR(alg);
+			goto err;
+		}
+
+		tfm = __crypto_alloc_tfm(alg, type, mask);
+		if (!IS_ERR(tfm))
+			return tfm;
+
+		crypto_mod_put(alg);
+		err = PTR_ERR(tfm);
+
+err:
+		if (err != -EAGAIN)
+			break;
+		if (signal_pending(current)) {
+			err = -EINTR;
+			break;
+		}
+	}
+
+	return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(crypto_alloc_base);
+
+void *crypto_create_tfm(struct crypto_alg *alg,
+			const struct crypto_type *frontend)
+{
+	char *mem;
+	struct crypto_tfm *tfm = NULL;
+	unsigned int tfmsize;
+	unsigned int total;
+	int err = -ENOMEM;
+
+	tfmsize = frontend->tfmsize;
+	total = tfmsize + sizeof(*tfm) + frontend->extsize(alg);
+
+	mem = kzalloc(total, GFP_KERNEL);
+	if (mem == NULL)
+		goto out_err;
+
+	tfm = (struct crypto_tfm *)(mem + tfmsize);
+	tfm->__crt_alg = alg;
+
+	err = frontend->init_tfm(tfm);
+	if (err)
+		goto out_free_tfm;
+
+	if (!tfm->exit && alg->cra_init && (err = alg->cra_init(tfm)))
+		goto cra_init_failed;
+
+	goto out;
+
+cra_init_failed:
+	crypto_exit_ops(tfm);
+out_free_tfm:
+	if (err == -EAGAIN)
+		crypto_shoot_alg(alg);
+	kfree(mem);
+out_err:
+	mem = ERR_PTR(err);
+out:
+	return mem;
+}
+EXPORT_SYMBOL_GPL(crypto_create_tfm);
+
+struct crypto_alg *crypto_find_alg(const char *alg_name,
+				   const struct crypto_type *frontend,
+				   u32 type, u32 mask)
+{
+	struct crypto_alg *(*lookup)(const char *name, u32 type, u32 mask) =
+		crypto_alg_mod_lookup;
+
+	if (frontend) {
+		type &= frontend->maskclear;
+		mask &= frontend->maskclear;
+		type |= frontend->type;
+		mask |= frontend->maskset;
+
+		if (frontend->lookup)
+			lookup = frontend->lookup;
+	}
+
+	return lookup(alg_name, type, mask);
+}
+EXPORT_SYMBOL_GPL(crypto_find_alg);
+
+/*
+ *	crypto_alloc_tfm - Locate algorithm and allocate transform
+ *	@alg_name: Name of algorithm
+ *	@frontend: Frontend algorithm type
+ *	@type: Type of algorithm
+ *	@mask: Mask for type comparison
+ *
+ *	crypto_alloc_tfm() will first attempt to locate an already loaded
+ *	algorithm.  If that fails and the kernel supports dynamically loadable
+ *	modules, it will then attempt to load a module of the same name or
+ *	alias.  If that fails it will send a query to any loaded crypto manager
+ *	to construct an algorithm on the fly.  A refcount is grabbed on the
+ *	algorithm which is then associated with the new transform.
+ *
+ *	The returned transform is of a non-determinate type.  Most people
+ *	should use one of the more specific allocation functions such as
+ *	crypto_alloc_blkcipher.
+ *
+ *	In case of error the return value is an error pointer.
+ */
+void *crypto_alloc_tfm(const char *alg_name,
+		       const struct crypto_type *frontend, u32 type, u32 mask)
+{
+	void *tfm;
+	int err;
+
+	for (;;) {
+		struct crypto_alg *alg;
+
+		alg = crypto_find_alg(alg_name, frontend, type, mask);
+		if (IS_ERR(alg)) {
+			err = PTR_ERR(alg);
+			goto err;
+		}
+
+		tfm = crypto_create_tfm(alg, frontend);
+		if (!IS_ERR(tfm))
+			return tfm;
+
+		crypto_mod_put(alg);
+		err = PTR_ERR(tfm);
+
+err:
+		if (err != -EAGAIN)
+			break;
+		if (signal_pending(current)) {
+			err = -EINTR;
+			break;
+		}
+	}
+
+	return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(crypto_alloc_tfm);
+
+/*
+ *	crypto_destroy_tfm - Free crypto transform
+ *	@mem: Start of tfm slab
+ *	@tfm: Transform to free
+ *
+ *	This function frees up the transform and any associated resources,
+ *	then drops the refcount on the associated algorithm.
+ */
+void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm)
+{
+	struct crypto_alg *alg;
+
+	if (unlikely(!mem))
+		return;
+
+	alg = tfm->__crt_alg;
+
+	if (!tfm->exit && alg->cra_exit)
+		alg->cra_exit(tfm);
+	crypto_exit_ops(tfm);
+	crypto_mod_put(alg);
+	kzfree(mem);
+}
+EXPORT_SYMBOL_GPL(crypto_destroy_tfm);
+
+int crypto_has_alg(const char *name, u32 type, u32 mask)
+{
+	int ret = 0;
+	struct crypto_alg *alg = crypto_alg_mod_lookup(name, type, mask);
+
+	if (!IS_ERR(alg)) {
+		crypto_mod_put(alg);
+		ret = 1;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(crypto_has_alg);
+
+MODULE_DESCRIPTION("Cryptographic core API");
+MODULE_LICENSE("GPL");