v4.19.13 snapshot.
diff --git a/crypto/echainiv.c b/crypto/echainiv.c
new file mode 100644
index 0000000..45819e6
--- /dev/null
+++ b/crypto/echainiv.c
@@ -0,0 +1,182 @@
+/*
+ * echainiv: Encrypted Chain IV Generator
+ *
+ * This generator generates an IV based on a sequence number by multiplying
+ * it with a salt and then encrypting it with the same key as used to encrypt
+ * the plain text. This algorithm requires that the block size be equal
+ * to the IV size. It is mainly useful for CBC.
+ *
+ * This generator can only be used by algorithms where authentication
+ * is performed after encryption (i.e., authenc).
+ *
+ * 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 <crypto/internal/geniv.h>
+#include <crypto/scatterwalk.h>
+#include <crypto/skcipher.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+
+static int echainiv_encrypt(struct aead_request *req)
+{
+ struct crypto_aead *geniv = crypto_aead_reqtfm(req);
+ struct aead_geniv_ctx *ctx = crypto_aead_ctx(geniv);
+ struct aead_request *subreq = aead_request_ctx(req);
+ __be64 nseqno;
+ u64 seqno;
+ u8 *info;
+ unsigned int ivsize = crypto_aead_ivsize(geniv);
+ int err;
+
+ if (req->cryptlen < ivsize)
+ return -EINVAL;
+
+ aead_request_set_tfm(subreq, ctx->child);
+
+ info = req->iv;
+
+ if (req->src != req->dst) {
+ SKCIPHER_REQUEST_ON_STACK(nreq, ctx->sknull);
+
+ skcipher_request_set_tfm(nreq, ctx->sknull);
+ skcipher_request_set_callback(nreq, req->base.flags,
+ NULL, NULL);
+ skcipher_request_set_crypt(nreq, req->src, req->dst,
+ req->assoclen + req->cryptlen,
+ NULL);
+
+ err = crypto_skcipher_encrypt(nreq);
+ if (err)
+ return err;
+ }
+
+ aead_request_set_callback(subreq, req->base.flags,
+ req->base.complete, req->base.data);
+ aead_request_set_crypt(subreq, req->dst, req->dst,
+ req->cryptlen, info);
+ aead_request_set_ad(subreq, req->assoclen);
+
+ memcpy(&nseqno, info + ivsize - 8, 8);
+ seqno = be64_to_cpu(nseqno);
+ memset(info, 0, ivsize);
+
+ scatterwalk_map_and_copy(info, req->dst, req->assoclen, ivsize, 1);
+
+ do {
+ u64 a;
+
+ memcpy(&a, ctx->salt + ivsize - 8, 8);
+
+ a |= 1;
+ a *= seqno;
+
+ memcpy(info + ivsize - 8, &a, 8);
+ } while ((ivsize -= 8));
+
+ return crypto_aead_encrypt(subreq);
+}
+
+static int echainiv_decrypt(struct aead_request *req)
+{
+ struct crypto_aead *geniv = crypto_aead_reqtfm(req);
+ struct aead_geniv_ctx *ctx = crypto_aead_ctx(geniv);
+ struct aead_request *subreq = aead_request_ctx(req);
+ crypto_completion_t compl;
+ void *data;
+ unsigned int ivsize = crypto_aead_ivsize(geniv);
+
+ if (req->cryptlen < ivsize)
+ return -EINVAL;
+
+ aead_request_set_tfm(subreq, ctx->child);
+
+ compl = req->base.complete;
+ data = req->base.data;
+
+ aead_request_set_callback(subreq, req->base.flags, compl, data);
+ aead_request_set_crypt(subreq, req->src, req->dst,
+ req->cryptlen - ivsize, req->iv);
+ aead_request_set_ad(subreq, req->assoclen + ivsize);
+
+ scatterwalk_map_and_copy(req->iv, req->src, req->assoclen, ivsize, 0);
+
+ return crypto_aead_decrypt(subreq);
+}
+
+static int echainiv_aead_create(struct crypto_template *tmpl,
+ struct rtattr **tb)
+{
+ struct aead_instance *inst;
+ int err;
+
+ inst = aead_geniv_alloc(tmpl, tb, 0, 0);
+
+ if (IS_ERR(inst))
+ return PTR_ERR(inst);
+
+ err = -EINVAL;
+ if (inst->alg.ivsize & (sizeof(u64) - 1) || !inst->alg.ivsize)
+ goto free_inst;
+
+ inst->alg.encrypt = echainiv_encrypt;
+ inst->alg.decrypt = echainiv_decrypt;
+
+ inst->alg.init = aead_init_geniv;
+ inst->alg.exit = aead_exit_geniv;
+
+ inst->alg.base.cra_ctxsize = sizeof(struct aead_geniv_ctx);
+ inst->alg.base.cra_ctxsize += inst->alg.ivsize;
+
+ inst->free = aead_geniv_free;
+
+ err = aead_register_instance(tmpl, inst);
+ if (err)
+ goto free_inst;
+
+out:
+ return err;
+
+free_inst:
+ aead_geniv_free(inst);
+ goto out;
+}
+
+static void echainiv_free(struct crypto_instance *inst)
+{
+ aead_geniv_free(aead_instance(inst));
+}
+
+static struct crypto_template echainiv_tmpl = {
+ .name = "echainiv",
+ .create = echainiv_aead_create,
+ .free = echainiv_free,
+ .module = THIS_MODULE,
+};
+
+static int __init echainiv_module_init(void)
+{
+ return crypto_register_template(&echainiv_tmpl);
+}
+
+static void __exit echainiv_module_exit(void)
+{
+ crypto_unregister_template(&echainiv_tmpl);
+}
+
+module_init(echainiv_module_init);
+module_exit(echainiv_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Encrypted Chain IV Generator");
+MODULE_ALIAS_CRYPTO("echainiv");