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-rw-r--r--crypto/api.c605
1 files changed, 605 insertions, 0 deletions
diff --git a/crypto/api.c b/crypto/api.c
new file mode 100644
index 000000000..5ffcd3ab4
--- /dev/null
+++ b/crypto/api.c
@@ -0,0 +1,605 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 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.
+ */
+
+#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/signal.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/completion.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 (!IS_ERR_OR_NULL(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);
+
+ refcount_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_killable_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 (IS_ERR(alg))
+ ;
+ 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;
+}
+
+static struct crypto_alg *crypto_alg_lookup(const char *name, u32 type,
+ u32 mask)
+{
+ struct crypto_alg *alg;
+ u32 test = 0;
+
+ if (!((type | mask) & CRYPTO_ALG_TESTED))
+ test |= CRYPTO_ALG_TESTED;
+
+ down_read(&crypto_alg_sem);
+ alg = __crypto_alg_lookup(name, type | test, mask | test);
+ if (!alg && test) {
+ alg = __crypto_alg_lookup(name, type, mask);
+ if (alg && !crypto_is_larval(alg)) {
+ /* Test failed */
+ crypto_mod_put(alg);
+ alg = ERR_PTR(-ELIBBAD);
+ }
+ }
+ up_read(&crypto_alg_sem);
+
+ return alg;
+}
+
+static struct crypto_alg *crypto_larval_lookup(const char *name, u32 type,
+ u32 mask)
+{
+ struct crypto_alg *alg;
+
+ if (!name)
+ return ERR_PTR(-ENOENT);
+
+ type &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
+ mask &= ~(CRYPTO_ALG_LARVAL | CRYPTO_ALG_DEAD);
+
+ alg = crypto_alg_lookup(name, type, mask);
+ if (!alg && !(mask & CRYPTO_NOLOAD)) {
+ 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 (!IS_ERR_OR_NULL(alg) && crypto_is_larval(alg))
+ alg = crypto_larval_wait(alg);
+ else if (!alg)
+ alg = crypto_larval_add(name, type, mask);
+
+ return alg;
+}
+
+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 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);
+ return 0;
+}
+
+static void crypto_exit_ops(struct crypto_tfm *tfm)
+{
+ const struct crypto_type *type = tfm->__crt_alg->cra_type;
+
+ if (type && tfm->exit)
+ tfm->exit(tfm);
+}
+
+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_skcipher().
+ *
+ * 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 (fatal_signal_pending(current)) {
+ err = -EINTR;
+ break;
+ }
+ }
+
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(crypto_alloc_base);
+
+void *crypto_create_tfm_node(struct crypto_alg *alg,
+ const struct crypto_type *frontend,
+ int node)
+{
+ 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_node(total, GFP_KERNEL, node);
+ if (mem == NULL)
+ goto out_err;
+
+ tfm = (struct crypto_tfm *)(mem + tfmsize);
+ tfm->__crt_alg = alg;
+ tfm->node = node;
+
+ 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_node);
+
+struct crypto_alg *crypto_find_alg(const char *alg_name,
+ const struct crypto_type *frontend,
+ u32 type, u32 mask)
+{
+ if (frontend) {
+ type &= frontend->maskclear;
+ mask &= frontend->maskclear;
+ type |= frontend->type;
+ mask |= frontend->maskset;
+ }
+
+ return crypto_alg_mod_lookup(alg_name, type, mask);
+}
+EXPORT_SYMBOL_GPL(crypto_find_alg);
+
+/*
+ * crypto_alloc_tfm_node - Locate algorithm and allocate transform
+ * @alg_name: Name of algorithm
+ * @frontend: Frontend algorithm type
+ * @type: Type of algorithm
+ * @mask: Mask for type comparison
+ * @node: NUMA node in which users desire to put requests, if node is
+ * NUMA_NO_NODE, it means users have no special requirement.
+ *
+ * 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_skcipher().
+ *
+ * In case of error the return value is an error pointer.
+ */
+
+void *crypto_alloc_tfm_node(const char *alg_name,
+ const struct crypto_type *frontend, u32 type, u32 mask,
+ int node)
+{
+ 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_node(alg, frontend, node);
+ if (!IS_ERR(tfm))
+ return tfm;
+
+ crypto_mod_put(alg);
+ err = PTR_ERR(tfm);
+
+err:
+ if (err != -EAGAIN)
+ break;
+ if (fatal_signal_pending(current)) {
+ err = -EINTR;
+ break;
+ }
+ }
+
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(crypto_alloc_tfm_node);
+
+/*
+ * 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 (IS_ERR_OR_NULL(mem))
+ return;
+
+ alg = tfm->__crt_alg;
+
+ if (!tfm->exit && alg->cra_exit)
+ alg->cra_exit(tfm);
+ crypto_exit_ops(tfm);
+ crypto_mod_put(alg);
+ kfree_sensitive(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);
+
+void crypto_req_done(struct crypto_async_request *req, int err)
+{
+ struct crypto_wait *wait = req->data;
+
+ if (err == -EINPROGRESS)
+ return;
+
+ wait->err = err;
+ complete(&wait->completion);
+}
+EXPORT_SYMBOL_GPL(crypto_req_done);
+
+MODULE_DESCRIPTION("Cryptographic core API");
+MODULE_LICENSE("GPL");
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