v4.19.13 snapshot.
diff --git a/crypto/jitterentropy-kcapi.c b/crypto/jitterentropy-kcapi.c
new file mode 100644
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--- /dev/null
+++ b/crypto/jitterentropy-kcapi.c
@@ -0,0 +1,207 @@
+/*
+ * Non-physical true random number generator based on timing jitter --
+ * Linux Kernel Crypto API specific code
+ *
+ * Copyright Stephan Mueller <smueller@chronox.de>, 2015
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, and the entire permission notice in its entirety,
+ * including the disclaimer of warranties.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote
+ * products derived from this software without specific prior
+ * written permission.
+ *
+ * ALTERNATIVELY, this product may be distributed under the terms of
+ * the GNU General Public License, in which case the provisions of the GPL2 are
+ * required INSTEAD OF the above restrictions. (This clause is
+ * necessary due to a potential bad interaction between the GPL and
+ * the restrictions contained in a BSD-style copyright.)
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF
+ * WHICH ARE HEREBY DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/fips.h>
+#include <linux/time.h>
+#include <linux/crypto.h>
+#include <crypto/internal/rng.h>
+
+struct rand_data;
+int jent_read_entropy(struct rand_data *ec, unsigned char *data,
+ unsigned int len);
+int jent_entropy_init(void);
+struct rand_data *jent_entropy_collector_alloc(unsigned int osr,
+ unsigned int flags);
+void jent_entropy_collector_free(struct rand_data *entropy_collector);
+
+/***************************************************************************
+ * Helper function
+ ***************************************************************************/
+
+__u64 jent_rol64(__u64 word, unsigned int shift)
+{
+ return rol64(word, shift);
+}
+
+void *jent_zalloc(unsigned int len)
+{
+ return kzalloc(len, GFP_KERNEL);
+}
+
+void jent_zfree(void *ptr)
+{
+ kzfree(ptr);
+}
+
+int jent_fips_enabled(void)
+{
+ return fips_enabled;
+}
+
+void jent_panic(char *s)
+{
+ panic("%s", s);
+}
+
+void jent_memcpy(void *dest, const void *src, unsigned int n)
+{
+ memcpy(dest, src, n);
+}
+
+/*
+ * Obtain a high-resolution time stamp value. The time stamp is used to measure
+ * the execution time of a given code path and its variations. Hence, the time
+ * stamp must have a sufficiently high resolution.
+ *
+ * Note, if the function returns zero because a given architecture does not
+ * implement a high-resolution time stamp, the RNG code's runtime test
+ * will detect it and will not produce output.
+ */
+void jent_get_nstime(__u64 *out)
+{
+ __u64 tmp = 0;
+
+ tmp = random_get_entropy();
+
+ /*
+ * If random_get_entropy does not return a value, i.e. it is not
+ * implemented for a given architecture, use a clock source.
+ * hoping that there are timers we can work with.
+ */
+ if (tmp == 0)
+ tmp = ktime_get_ns();
+
+ *out = tmp;
+}
+
+/***************************************************************************
+ * Kernel crypto API interface
+ ***************************************************************************/
+
+struct jitterentropy {
+ spinlock_t jent_lock;
+ struct rand_data *entropy_collector;
+};
+
+static int jent_kcapi_init(struct crypto_tfm *tfm)
+{
+ struct jitterentropy *rng = crypto_tfm_ctx(tfm);
+ int ret = 0;
+
+ rng->entropy_collector = jent_entropy_collector_alloc(1, 0);
+ if (!rng->entropy_collector)
+ ret = -ENOMEM;
+
+ spin_lock_init(&rng->jent_lock);
+ return ret;
+}
+
+static void jent_kcapi_cleanup(struct crypto_tfm *tfm)
+{
+ struct jitterentropy *rng = crypto_tfm_ctx(tfm);
+
+ spin_lock(&rng->jent_lock);
+ if (rng->entropy_collector)
+ jent_entropy_collector_free(rng->entropy_collector);
+ rng->entropy_collector = NULL;
+ spin_unlock(&rng->jent_lock);
+}
+
+static int jent_kcapi_random(struct crypto_rng *tfm,
+ const u8 *src, unsigned int slen,
+ u8 *rdata, unsigned int dlen)
+{
+ struct jitterentropy *rng = crypto_rng_ctx(tfm);
+ int ret = 0;
+
+ spin_lock(&rng->jent_lock);
+ ret = jent_read_entropy(rng->entropy_collector, rdata, dlen);
+ spin_unlock(&rng->jent_lock);
+
+ return ret;
+}
+
+static int jent_kcapi_reset(struct crypto_rng *tfm,
+ const u8 *seed, unsigned int slen)
+{
+ return 0;
+}
+
+static struct rng_alg jent_alg = {
+ .generate = jent_kcapi_random,
+ .seed = jent_kcapi_reset,
+ .seedsize = 0,
+ .base = {
+ .cra_name = "jitterentropy_rng",
+ .cra_driver_name = "jitterentropy_rng",
+ .cra_priority = 100,
+ .cra_ctxsize = sizeof(struct jitterentropy),
+ .cra_module = THIS_MODULE,
+ .cra_init = jent_kcapi_init,
+ .cra_exit = jent_kcapi_cleanup,
+
+ }
+};
+
+static int __init jent_mod_init(void)
+{
+ int ret = 0;
+
+ ret = jent_entropy_init();
+ if (ret) {
+ pr_info("jitterentropy: Initialization failed with host not compliant with requirements: %d\n", ret);
+ return -EFAULT;
+ }
+ return crypto_register_rng(&jent_alg);
+}
+
+static void __exit jent_mod_exit(void)
+{
+ crypto_unregister_rng(&jent_alg);
+}
+
+module_init(jent_mod_init);
+module_exit(jent_mod_exit);
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Stephan Mueller <smueller@chronox.de>");
+MODULE_DESCRIPTION("Non-physical True Random Number Generator based on CPU Jitter");
+MODULE_ALIAS_CRYPTO("jitterentropy_rng");