crypto: morus - Add generic MORUS AEAD implementations

This patch adds the generic implementation of the MORUS family of AEAD
algorithms (MORUS-640 and MORUS-1280). The original authors of MORUS
are Hongjun Wu and Tao Huang.

At the time of writing, MORUS is one of the finalists in CAESAR, an
open competition intended to select a portfolio of alternatives to
the problematic AES-GCM:

https://competitions.cr.yp.to/caesar-submissions.html
https://competitions.cr.yp.to/round3/morusv2.pdf

Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 544 insertions, 0 deletions

diff --git a/crypto/morus640.c b/crypto/morus640.c
new file mode 100644
index 000000000000..9fbcde307daf
--- /dev/null
+++ b/crypto/morus640.c
@@ -0,0 +1,544 @@
+/*
+ * The MORUS-640 Authenticated-Encryption Algorithm
+ *
+ * Copyright (c) 2016-2018 Ondrej Mosnacek <omosnacek@gmail.com>
+ * Copyright (C) 2017-2018 Red Hat, Inc. All rights reserved.
+ *
+ * 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 <asm/unaligned.h>
+#include <crypto/algapi.h>
+#include <crypto/internal/aead.h>
+#include <crypto/internal/skcipher.h>
+#include <crypto/morus_common.h>
+#include <crypto/scatterwalk.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/scatterlist.h>
+
+#define MORUS640_WORD_SIZE 4
+#define MORUS640_BLOCK_SIZE (MORUS_BLOCK_WORDS * MORUS640_WORD_SIZE)
+#define MORUS640_BLOCK_ALIGN (__alignof__(__le32))
+#define MORUS640_ALIGNED(p) IS_ALIGNED((uintptr_t)p, MORUS640_BLOCK_ALIGN)
+
+struct morus640_block {
+        u32 words[MORUS_BLOCK_WORDS];
+};
+
+union morus640_block_in {
+        __le32 words[MORUS_BLOCK_WORDS];
+        u8 bytes[MORUS640_BLOCK_SIZE];
+};
+
+struct morus640_state {
+        struct morus640_block s[MORUS_STATE_BLOCKS];
+};
+
+struct morus640_ctx {
+        struct morus640_block key;
+};
+
+struct morus640_ops {
+        int (*skcipher_walk_init)(struct skcipher_walk *walk,
+                                  struct aead_request *req, bool atomic);
+
+        void (*crypt_chunk)(struct morus640_state *state,
+                            u8 *dst, const u8 *src, unsigned int size);
+};
+
+static const struct morus640_block crypto_morus640_const[2] = {
+        { .words = {
+                U32_C(0x02010100),
+                U32_C(0x0d080503),
+                U32_C(0x59372215),
+                U32_C(0x6279e990),
+        } },
+        { .words = {
+                U32_C(0x55183ddb),
+                U32_C(0xf12fc26d),
+                U32_C(0x42311120),
+                U32_C(0xdd28b573),
+        } },
+};
+
+static void crypto_morus640_round(struct morus640_block *b0,
+                                  struct morus640_block *b1,
+                                  struct morus640_block *b2,
+                                  struct morus640_block *b3,
+                                  struct morus640_block *b4,
+                                  const struct morus640_block *m,
+                                  unsigned int b, unsigned int w)
+{
+        unsigned int i;
+        struct morus640_block tmp;
+
+        for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
+                b0->words[i] ^= b1->words[i] & b2->words[i];
+                b0->words[i] ^= b3->words[i];
+                b0->words[i] ^= m->words[i];
+                b0->words[i] = rol32(b0->words[i], b);
+        }
+
+        tmp = *b3;
+        for (i = 0; i < MORUS_BLOCK_WORDS; i++)
+                b3->words[(i + w) % MORUS_BLOCK_WORDS] = tmp.words[i];
+}
+
+static void crypto_morus640_update(struct morus640_state *state,
+                                   const struct morus640_block *m)
+{
+        static const struct morus640_block z = {};
+
+        struct morus640_block *s = state->s;
+
+        crypto_morus640_round(&s[0], &s[1], &s[2], &s[3], &s[4], &z,  5, 1);
+        crypto_morus640_round(&s[1], &s[2], &s[3], &s[4], &s[0], m,  31, 2);
+        crypto_morus640_round(&s[2], &s[3], &s[4], &s[0], &s[1], m,   7, 3);
+        crypto_morus640_round(&s[3], &s[4], &s[0], &s[1], &s[2], m,  22, 2);
+        crypto_morus640_round(&s[4], &s[0], &s[1], &s[2], &s[3], m,  13, 1);
+}
+
+static void crypto_morus640_load_a(struct morus640_block *dst, const u8 *src)
+{
+        unsigned int i;
+        for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
+                dst->words[i] = le32_to_cpu(*(const __le32 *)src);
+                src += MORUS640_WORD_SIZE;
+        }
+}
+
+static void crypto_morus640_load_u(struct morus640_block *dst, const u8 *src)
+{
+        unsigned int i;
+        for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
+                dst->words[i] = get_unaligned_le32(src);
+                src += MORUS640_WORD_SIZE;
+        }
+}
+
+static void crypto_morus640_load(struct morus640_block *dst, const u8 *src)
+{
+        if (MORUS640_ALIGNED(src))
+                crypto_morus640_load_a(dst, src);
+        else
+                crypto_morus640_load_u(dst, src);
+}
+
+static void crypto_morus640_store_a(u8 *dst, const struct morus640_block *src)
+{
+        unsigned int i;
+        for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
+                *(__le32 *)dst = cpu_to_le32(src->words[i]);
+                dst += MORUS640_WORD_SIZE;
+        }
+}
+
+static void crypto_morus640_store_u(u8 *dst, const struct morus640_block *src)
+{
+        unsigned int i;
+        for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
+                put_unaligned_le32(src->words[i], dst);
+                dst += MORUS640_WORD_SIZE;
+        }
+}
+
+static void crypto_morus640_store(u8 *dst, const struct morus640_block *src)
+{
+        if (MORUS640_ALIGNED(dst))
+                crypto_morus640_store_a(dst, src);
+        else
+                crypto_morus640_store_u(dst, src);
+}
+
+static void crypto_morus640_ad(struct morus640_state *state, const u8 *src,
+                               unsigned int size)
+{
+        struct morus640_block m;
+
+        if (MORUS640_ALIGNED(src)) {
+                while (size >= MORUS640_BLOCK_SIZE) {
+                        crypto_morus640_load_a(&m, src);
+                        crypto_morus640_update(state, &m);
+
+                        size -= MORUS640_BLOCK_SIZE;
+                        src += MORUS640_BLOCK_SIZE;
+                }
+        } else {
+                while (size >= MORUS640_BLOCK_SIZE) {
+                        crypto_morus640_load_u(&m, src);
+                        crypto_morus640_update(state, &m);
+
+                        size -= MORUS640_BLOCK_SIZE;
+                        src += MORUS640_BLOCK_SIZE;
+                }
+        }
+}
+
+static void crypto_morus640_core(const struct morus640_state *state,
+                                 struct morus640_block *blk)
+{
+        unsigned int i;
+
+        for (i = 0; i < MORUS_BLOCK_WORDS; i++)
+                blk->words[(i + 3) % MORUS_BLOCK_WORDS] ^= state->s[1].words[i];
+
+        for (i = 0; i < MORUS_BLOCK_WORDS; i++) {
+                blk->words[i] ^= state->s[0].words[i];
+                blk->words[i] ^= state->s[2].words[i] & state->s[3].words[i];
+        }
+}
+
+static void crypto_morus640_encrypt_chunk(struct morus640_state *state, u8 *dst,
+                                          const u8 *src, unsigned int size)
+{
+        struct morus640_block c, m;
+
+        if (MORUS640_ALIGNED(src) && MORUS640_ALIGNED(dst)) {
+                while (size >= MORUS640_BLOCK_SIZE) {
+                        crypto_morus640_load_a(&m, src);
+                        c = m;
+                        crypto_morus640_core(state, &c);
+                        crypto_morus640_store_a(dst, &c);
+                        crypto_morus640_update(state, &m);
+
+                        src += MORUS640_BLOCK_SIZE;
+                        dst += MORUS640_BLOCK_SIZE;
+                        size -= MORUS640_BLOCK_SIZE;
+                }
+        } else {
+                while (size >= MORUS640_BLOCK_SIZE) {
+                        crypto_morus640_load_u(&m, src);
+                        c = m;
+                        crypto_morus640_core(state, &c);
+                        crypto_morus640_store_u(dst, &c);
+                        crypto_morus640_update(state, &m);
+
+                        src += MORUS640_BLOCK_SIZE;
+                        dst += MORUS640_BLOCK_SIZE;
+                        size -= MORUS640_BLOCK_SIZE;
+                }
+        }
+
+        if (size > 0) {
+                union morus640_block_in tail;
+
+                memcpy(tail.bytes, src, size);
+                memset(tail.bytes + size, 0, MORUS640_BLOCK_SIZE - size);
+
+                crypto_morus640_load_a(&m, tail.bytes);
+                c = m;
+                crypto_morus640_core(state, &c);
+                crypto_morus640_store_a(tail.bytes, &c);
+                crypto_morus640_update(state, &m);
+
+                memcpy(dst, tail.bytes, size);
+        }
+}
+
+static void crypto_morus640_decrypt_chunk(struct morus640_state *state, u8 *dst,
+                                          const u8 *src, unsigned int size)
+{
+        struct morus640_block m;
+
+        if (MORUS640_ALIGNED(src) && MORUS640_ALIGNED(dst)) {
+                while (size >= MORUS640_BLOCK_SIZE) {
+                        crypto_morus640_load_a(&m, src);
+                        crypto_morus640_core(state, &m);
+                        crypto_morus640_store_a(dst, &m);
+                        crypto_morus640_update(state, &m);
+
+                        src += MORUS640_BLOCK_SIZE;
+                        dst += MORUS640_BLOCK_SIZE;
+                        size -= MORUS640_BLOCK_SIZE;
+                }
+        } else {
+                while (size >= MORUS640_BLOCK_SIZE) {
+                        crypto_morus640_load_u(&m, src);
+                        crypto_morus640_core(state, &m);
+                        crypto_morus640_store_u(dst, &m);
+                        crypto_morus640_update(state, &m);
+
+                        src += MORUS640_BLOCK_SIZE;
+                        dst += MORUS640_BLOCK_SIZE;
+                        size -= MORUS640_BLOCK_SIZE;
+                }
+        }
+
+        if (size > 0) {
+                union morus640_block_in tail;
+
+                memcpy(tail.bytes, src, size);
+
+                crypto_morus640_load_a(&m, src);
+                crypto_morus640_core(state, &m);
+                crypto_morus640_store_a(tail.bytes, &m);
+                memset(tail.bytes + size, 0, MORUS640_BLOCK_SIZE - size);
+                crypto_morus640_load_a(&m, tail.bytes);
+                crypto_morus640_update(state, &m);
+
+                memcpy(dst, tail.bytes, size);
+        }
+}
+
+static void crypto_morus640_init(struct morus640_state *state,
+                                 const struct morus640_block *key,
+                                 const u8 *iv)
+{
+        static const struct morus640_block z = {};
+
+        unsigned int i;
+
+        crypto_morus640_load(&state->s[0], iv);
+        state->s[1] = *key;
+        for (i = 0; i < MORUS_BLOCK_WORDS; i++)
+                state->s[2].words[i] = U32_C(0xFFFFFFFF);
+        state->s[3] = crypto_morus640_const[0];
+        state->s[4] = crypto_morus640_const[1];
+
+        for (i = 0; i < 16; i++)
+                crypto_morus640_update(state, &z);
+
+        for (i = 0; i < MORUS_BLOCK_WORDS; i++)
+                state->s[1].words[i] ^= key->words[i];
+}
+
+static void crypto_morus640_process_ad(struct morus640_state *state,
+                                       struct scatterlist *sg_src,
+                                       unsigned int assoclen)
+{
+        struct scatter_walk walk;
+        struct morus640_block m;
+        union morus640_block_in buf;
+        unsigned int pos = 0;
+
+        scatterwalk_start(&walk, sg_src);
+        while (assoclen != 0) {
+                unsigned int size = scatterwalk_clamp(&walk, assoclen);
+                unsigned int left = size;
+                void *mapped = scatterwalk_map(&walk);
+                const u8 *src = (const u8 *)mapped;
+
+                if (pos + size >= MORUS640_BLOCK_SIZE) {
+                        if (pos > 0) {
+                                unsigned int fill = MORUS640_BLOCK_SIZE - pos;
+                                memcpy(buf.bytes + pos, src, fill);
+
+                                crypto_morus640_load_a(&m, buf.bytes);
+                                crypto_morus640_update(state, &m);
+
+                                pos = 0;
+                                left -= fill;
+                                src += fill;
+                        }
+
+                        crypto_morus640_ad(state, src, left);
+                        src += left & ~(MORUS640_BLOCK_SIZE - 1);
+                        left &= MORUS640_BLOCK_SIZE - 1;
+                }
+
+                memcpy(buf.bytes + pos, src, left);
+
+                pos += left;
+                assoclen -= size;
+                scatterwalk_unmap(mapped);
+                scatterwalk_advance(&walk, size);
+                scatterwalk_done(&walk, 0, assoclen);
+        }
+
+        if (pos > 0) {
+                memset(buf.bytes + pos, 0, MORUS640_BLOCK_SIZE - pos);
+
+                crypto_morus640_load_a(&m, buf.bytes);
+                crypto_morus640_update(state, &m);
+        }
+}
+
+static void crypto_morus640_process_crypt(struct morus640_state *state,
+                                          struct aead_request *req,
+                                          const struct morus640_ops *ops)
+{
+        struct skcipher_walk walk;
+        u8 *dst;
+        const u8 *src;
+
+        ops->skcipher_walk_init(&walk, req, false);
+
+        while (walk.nbytes) {
+                src = walk.src.virt.addr;
+                dst = walk.dst.virt.addr;
+
+                ops->crypt_chunk(state, dst, src, walk.nbytes);
+
+                skcipher_walk_done(&walk, 0);
+        }
+}
+
+static void crypto_morus640_final(struct morus640_state *state,
+                                  struct morus640_block *tag_xor,
+                                  u64 assoclen, u64 cryptlen)
+{
+        u64 assocbits = assoclen * 8;
+        u64 cryptbits = cryptlen * 8;
+
+        u32 assocbits_lo = (u32)assocbits;
+        u32 assocbits_hi = (u32)(assocbits >> 32);
+        u32 cryptbits_lo = (u32)cryptbits;
+        u32 cryptbits_hi = (u32)(cryptbits >> 32);
+
+        struct morus640_block tmp;
+        unsigned int i;
+
+        tmp.words[0] = cpu_to_le32(assocbits_lo);
+        tmp.words[1] = cpu_to_le32(assocbits_hi);
+        tmp.words[2] = cpu_to_le32(cryptbits_lo);
+        tmp.words[3] = cpu_to_le32(cryptbits_hi);
+
+        for (i = 0; i < MORUS_BLOCK_WORDS; i++)
+                state->s[4].words[i] ^= state->s[0].words[i];
+
+        for (i = 0; i < 10; i++)
+                crypto_morus640_update(state, &tmp);
+
+        crypto_morus640_core(state, tag_xor);
+}
+
+static int crypto_morus640_setkey(struct crypto_aead *aead, const u8 *key,
+                                  unsigned int keylen)
+{
+        struct morus640_ctx *ctx = crypto_aead_ctx(aead);
+
+        if (keylen != MORUS640_BLOCK_SIZE) {
+                crypto_aead_set_flags(aead, CRYPTO_TFM_RES_BAD_KEY_LEN);
+                return -EINVAL;
+        }
+
+        crypto_morus640_load(&ctx->key, key);
+        return 0;
+}
+
+static int crypto_morus640_setauthsize(struct crypto_aead *tfm,
+                                       unsigned int authsize)
+{
+        return (authsize <= MORUS_MAX_AUTH_SIZE) ? 0 : -EINVAL;
+}
+
+static void crypto_morus640_crypt(struct aead_request *req,
+                                  struct morus640_block *tag_xor,
+                                  unsigned int cryptlen,
+                                  const struct morus640_ops *ops)
+{
+        struct crypto_aead *tfm = crypto_aead_reqtfm(req);
+        struct morus640_ctx *ctx = crypto_aead_ctx(tfm);
+        struct morus640_state state;
+
+        crypto_morus640_init(&state, &ctx->key, req->iv);
+        crypto_morus640_process_ad(&state, req->src, req->assoclen);
+        crypto_morus640_process_crypt(&state, req, ops);
+        crypto_morus640_final(&state, tag_xor, req->assoclen, cryptlen);
+}
+
+static int crypto_morus640_encrypt(struct aead_request *req)
+{
+        static const struct morus640_ops ops = {
+                .skcipher_walk_init = skcipher_walk_aead_encrypt,
+                .crypt_chunk = crypto_morus640_encrypt_chunk,
+        };
+
+        struct crypto_aead *tfm = crypto_aead_reqtfm(req);
+        struct morus640_block tag = {};
+        union morus640_block_in tag_out;
+        unsigned int authsize = crypto_aead_authsize(tfm);
+        unsigned int cryptlen = req->cryptlen;
+
+        crypto_morus640_crypt(req, &tag, cryptlen, &ops);
+        crypto_morus640_store(tag_out.bytes, &tag);
+
+        scatterwalk_map_and_copy(tag_out.bytes, req->dst,
+                                 req->assoclen + cryptlen, authsize, 1);
+        return 0;
+}
+
+static int crypto_morus640_decrypt(struct aead_request *req)
+{
+        static const struct morus640_ops ops = {
+                .skcipher_walk_init = skcipher_walk_aead_decrypt,
+                .crypt_chunk = crypto_morus640_decrypt_chunk,
+        };
+        static const u8 zeros[MORUS640_BLOCK_SIZE] = {};
+
+        struct crypto_aead *tfm = crypto_aead_reqtfm(req);
+        union morus640_block_in tag_in;
+        struct morus640_block tag;
+        unsigned int authsize = crypto_aead_authsize(tfm);
+        unsigned int cryptlen = req->cryptlen - authsize;
+
+        scatterwalk_map_and_copy(tag_in.bytes, req->src,
+                                 req->assoclen + cryptlen, authsize, 0);
+
+        crypto_morus640_load(&tag, tag_in.bytes);
+        crypto_morus640_crypt(req, &tag, cryptlen, &ops);
+        crypto_morus640_store(tag_in.bytes, &tag);
+
+        return crypto_memneq(tag_in.bytes, zeros, authsize) ? -EBADMSG : 0;
+}
+
+static int crypto_morus640_init_tfm(struct crypto_aead *tfm)
+{
+        return 0;
+}
+
+static void crypto_morus640_exit_tfm(struct crypto_aead *tfm)
+{
+}
+
+static struct aead_alg crypto_morus640_alg = {
+        .setkey = crypto_morus640_setkey,
+        .setauthsize = crypto_morus640_setauthsize,
+        .encrypt = crypto_morus640_encrypt,
+        .decrypt = crypto_morus640_decrypt,
+        .init = crypto_morus640_init_tfm,
+        .exit = crypto_morus640_exit_tfm,
+
+        .ivsize = MORUS_NONCE_SIZE,
+        .maxauthsize = MORUS_MAX_AUTH_SIZE,
+        .chunksize = MORUS640_BLOCK_SIZE,
+
+        .base = {
+                .cra_flags = CRYPTO_ALG_TYPE_AEAD,
+                .cra_blocksize = 1,
+                .cra_ctxsize = sizeof(struct morus640_ctx),
+                .cra_alignmask = 0,
+
+                .cra_priority = 100,
+
+                .cra_name = "morus640",
+                .cra_driver_name = "morus640-generic",
+
+                .cra_module = THIS_MODULE,
+        }
+};
+
+static int __init crypto_morus640_module_init(void)
+{
+        return crypto_register_aead(&crypto_morus640_alg);
+}
+
+static void __exit crypto_morus640_module_exit(void)
+{
+        crypto_unregister_aead(&crypto_morus640_alg);
+}
+
+module_init(crypto_morus640_module_init);
+module_exit(crypto_morus640_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Ondrej Mosnacek <omosnacek@gmail.com>");
+MODULE_DESCRIPTION("MORUS-640 AEAD algorithm");
+MODULE_ALIAS_CRYPTO("morus640");
+MODULE_ALIAS_CRYPTO("morus640-generic");