v4.19.13 snapshot.
diff --git a/crypto/rng.c b/crypto/rng.c
new file mode 100644
index 0000000..b4a6186
--- /dev/null
+++ b/crypto/rng.c
@@ -0,0 +1,234 @@
+/*
+ * Cryptographic API.
+ *
+ * RNG operations.
+ *
+ * Copyright (c) 2008 Neil Horman <nhorman@tuxdriver.com>
+ * Copyright (c) 2015 Herbert Xu <herbert@gondor.apana.org.au>
+ *
+ * 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/atomic.h>
+#include <crypto/internal/rng.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/random.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/cryptouser.h>
+#include <linux/compiler.h>
+#include <net/netlink.h>
+
+#include "internal.h"
+
+static DEFINE_MUTEX(crypto_default_rng_lock);
+struct crypto_rng *crypto_default_rng;
+EXPORT_SYMBOL_GPL(crypto_default_rng);
+static int crypto_default_rng_refcnt;
+
+int crypto_rng_reset(struct crypto_rng *tfm, const u8 *seed, unsigned int slen)
+{
+ u8 *buf = NULL;
+ int err;
+
+ if (!seed && slen) {
+ buf = kmalloc(slen, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ err = get_random_bytes_wait(buf, slen);
+ if (err)
+ goto out;
+ seed = buf;
+ }
+
+ err = crypto_rng_alg(tfm)->seed(tfm, seed, slen);
+out:
+ kzfree(buf);
+ return err;
+}
+EXPORT_SYMBOL_GPL(crypto_rng_reset);
+
+static int crypto_rng_init_tfm(struct crypto_tfm *tfm)
+{
+ return 0;
+}
+
+static unsigned int seedsize(struct crypto_alg *alg)
+{
+ struct rng_alg *ralg = container_of(alg, struct rng_alg, base);
+
+ return ralg->seedsize;
+}
+
+#ifdef CONFIG_NET
+static int crypto_rng_report(struct sk_buff *skb, struct crypto_alg *alg)
+{
+ struct crypto_report_rng rrng;
+
+ strncpy(rrng.type, "rng", sizeof(rrng.type));
+
+ rrng.seedsize = seedsize(alg);
+
+ if (nla_put(skb, CRYPTOCFGA_REPORT_RNG,
+ sizeof(struct crypto_report_rng), &rrng))
+ goto nla_put_failure;
+ return 0;
+
+nla_put_failure:
+ return -EMSGSIZE;
+}
+#else
+static int crypto_rng_report(struct sk_buff *skb, struct crypto_alg *alg)
+{
+ return -ENOSYS;
+}
+#endif
+
+static void crypto_rng_show(struct seq_file *m, struct crypto_alg *alg)
+ __maybe_unused;
+static void crypto_rng_show(struct seq_file *m, struct crypto_alg *alg)
+{
+ seq_printf(m, "type : rng\n");
+ seq_printf(m, "seedsize : %u\n", seedsize(alg));
+}
+
+static const struct crypto_type crypto_rng_type = {
+ .extsize = crypto_alg_extsize,
+ .init_tfm = crypto_rng_init_tfm,
+#ifdef CONFIG_PROC_FS
+ .show = crypto_rng_show,
+#endif
+ .report = crypto_rng_report,
+ .maskclear = ~CRYPTO_ALG_TYPE_MASK,
+ .maskset = CRYPTO_ALG_TYPE_MASK,
+ .type = CRYPTO_ALG_TYPE_RNG,
+ .tfmsize = offsetof(struct crypto_rng, base),
+};
+
+struct crypto_rng *crypto_alloc_rng(const char *alg_name, u32 type, u32 mask)
+{
+ return crypto_alloc_tfm(alg_name, &crypto_rng_type, type, mask);
+}
+EXPORT_SYMBOL_GPL(crypto_alloc_rng);
+
+int crypto_get_default_rng(void)
+{
+ struct crypto_rng *rng;
+ int err;
+
+ mutex_lock(&crypto_default_rng_lock);
+ if (!crypto_default_rng) {
+ rng = crypto_alloc_rng("stdrng", 0, 0);
+ err = PTR_ERR(rng);
+ if (IS_ERR(rng))
+ goto unlock;
+
+ err = crypto_rng_reset(rng, NULL, crypto_rng_seedsize(rng));
+ if (err) {
+ crypto_free_rng(rng);
+ goto unlock;
+ }
+
+ crypto_default_rng = rng;
+ }
+
+ crypto_default_rng_refcnt++;
+ err = 0;
+
+unlock:
+ mutex_unlock(&crypto_default_rng_lock);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(crypto_get_default_rng);
+
+void crypto_put_default_rng(void)
+{
+ mutex_lock(&crypto_default_rng_lock);
+ crypto_default_rng_refcnt--;
+ mutex_unlock(&crypto_default_rng_lock);
+}
+EXPORT_SYMBOL_GPL(crypto_put_default_rng);
+
+#if defined(CONFIG_CRYPTO_RNG) || defined(CONFIG_CRYPTO_RNG_MODULE)
+int crypto_del_default_rng(void)
+{
+ int err = -EBUSY;
+
+ mutex_lock(&crypto_default_rng_lock);
+ if (crypto_default_rng_refcnt)
+ goto out;
+
+ crypto_free_rng(crypto_default_rng);
+ crypto_default_rng = NULL;
+
+ err = 0;
+
+out:
+ mutex_unlock(&crypto_default_rng_lock);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(crypto_del_default_rng);
+#endif
+
+int crypto_register_rng(struct rng_alg *alg)
+{
+ struct crypto_alg *base = &alg->base;
+
+ if (alg->seedsize > PAGE_SIZE / 8)
+ return -EINVAL;
+
+ base->cra_type = &crypto_rng_type;
+ base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
+ base->cra_flags |= CRYPTO_ALG_TYPE_RNG;
+
+ return crypto_register_alg(base);
+}
+EXPORT_SYMBOL_GPL(crypto_register_rng);
+
+void crypto_unregister_rng(struct rng_alg *alg)
+{
+ crypto_unregister_alg(&alg->base);
+}
+EXPORT_SYMBOL_GPL(crypto_unregister_rng);
+
+int crypto_register_rngs(struct rng_alg *algs, int count)
+{
+ int i, ret;
+
+ for (i = 0; i < count; i++) {
+ ret = crypto_register_rng(algs + i);
+ if (ret)
+ goto err;
+ }
+
+ return 0;
+
+err:
+ for (--i; i >= 0; --i)
+ crypto_unregister_rng(algs + i);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(crypto_register_rngs);
+
+void crypto_unregister_rngs(struct rng_alg *algs, int count)
+{
+ int i;
+
+ for (i = count - 1; i >= 0; --i)
+ crypto_unregister_rng(algs + i);
+}
+EXPORT_SYMBOL_GPL(crypto_unregister_rngs);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Random Number Generator");