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Date:      Sat, 15 Apr 2017 20:51:53 +0000 (UTC)
From:      =?UTF-8?Q?Dag-Erling_Sm=c3=b8rgrav?= <des@FreeBSD.org>
To:        src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org
Subject:   svn commit: r316982 - in head/sys: conf crypto/chacha20 modules modules/chacha20
Message-ID:  <201704152051.v3FKpr38020502@repo.freebsd.org>

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Author: des
Date: Sat Apr 15 20:51:53 2017
New Revision: 316982
URL: https://svnweb.freebsd.org/changeset/base/316982

Log:
  3BSD-licensed implementation of the chacha20 stream cipher, intended for
  use by the upcoming arc4random replacement.

Added:
  head/sys/crypto/chacha20/
  head/sys/crypto/chacha20/chacha20.c   (contents, props changed)
  head/sys/crypto/chacha20/chacha20.h   (contents, props changed)
  head/sys/modules/chacha20/
  head/sys/modules/chacha20/Makefile   (contents, props changed)
Modified:
  head/sys/conf/files
  head/sys/modules/Makefile

Modified: head/sys/conf/files
==============================================================================
--- head/sys/conf/files	Sat Apr 15 20:37:34 2017	(r316981)
+++ head/sys/conf/files	Sat Apr 15 20:51:53 2017	(r316982)
@@ -591,6 +591,7 @@ crypto/blowfish/bf_ecb.c	optional ipsec 
 crypto/blowfish/bf_skey.c	optional crypto | ipsec | ipsec_support
 crypto/camellia/camellia.c	optional crypto | ipsec | ipsec_support
 crypto/camellia/camellia-api.c	optional crypto | ipsec | ipsec_support
+crypto/chacha20/chacha20.c	optional chacha20
 crypto/des/des_ecb.c		optional crypto | ipsec | ipsec_support | netsmb
 crypto/des/des_setkey.c		optional crypto | ipsec | ipsec_support | netsmb
 crypto/rc4/rc4.c		optional netgraph_mppc_encryption | kgssapi

Added: head/sys/crypto/chacha20/chacha20.c
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ head/sys/crypto/chacha20/chacha20.c	Sat Apr 15 20:51:53 2017	(r316982)
@@ -0,0 +1,210 @@
+/*-
+ * Copyright (c) 2017 Dag-Erling Smørgrav
+ * All rights reserved.
+ *
+ * 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, this list of conditions and the following disclaimer.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 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 ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#ifdef _KERNEL
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/libkern.h>
+#include <sys/module.h>
+#include <sys/syslog.h>
+#include <sys/systm.h>
+#else
+#include <stdint.h>
+#include <string.h>
+#endif
+
+#include <sys/endian.h>
+
+
+#include <crypto/chacha20/chacha20.h>
+
+#define rol32(x, n) \
+	((x) << ((n) & 0x1f) | (x) >> (-(n) & 0x1f))
+
+#define CHACHA_QR(x, a, b, c, d)					\
+	do {								\
+		x[a] = x[a] + x[b]; x[d] = rol32(x[d] ^ x[a], 16);	\
+		x[c] = x[c] + x[d]; x[b] = rol32(x[b] ^ x[c], 12);	\
+		x[a] = x[a] + x[b]; x[d] = rol32(x[d] ^ x[a],  8);	\
+		x[c] = x[c] + x[d]; x[b] = rol32(x[b] ^ x[c],  7);	\
+	} while (0)
+
+static const char magic128[] = "expand 16-byte k";
+static const char magic256[] = "expand 32-byte k";
+
+/*
+ * Fill the state array with 16 bytes of magic and 32 bytes of key,
+ * repeating the key if necessary.  The 8-byte stream position and the
+ * 8-byte nonce are initialized to all-zeroes.
+ */
+void
+chacha20_init(chacha20_ctx *ctx, const uint8_t *key, size_t keylen)
+{
+
+	memset(ctx, 0, sizeof *ctx);
+	if (keylen == 32) {
+		/* magic */
+		ctx->state[ 0] = le32dec(magic256 + 0);
+		ctx->state[ 1] = le32dec(magic256 + 4);
+		ctx->state[ 2] = le32dec(magic256 + 8);
+		ctx->state[ 3] = le32dec(magic256 + 12);
+		/* first half of key */
+		ctx->state[ 4] = le32dec(key + 0);
+		ctx->state[ 5] = le32dec(key + 4);
+		ctx->state[ 6] = le32dec(key + 8);
+		ctx->state[ 7] = le32dec(key + 12);
+		/* second half of key */
+		ctx->state[ 8] = le32dec(key + 16);
+		ctx->state[ 9] = le32dec(key + 20);
+		ctx->state[10] = le32dec(key + 24);
+		ctx->state[11] = le32dec(key + 28);
+	} else {
+		/* magic */
+		ctx->state[ 0] = le32dec(magic128 + 0);
+		ctx->state[ 1] = le32dec(magic128 + 4);
+		ctx->state[ 2] = le32dec(magic128 + 8);
+		ctx->state[ 3] = le32dec(magic128 + 12);
+		/* first half of key */
+		ctx->state[ 4] = le32dec(key + 0);
+		ctx->state[ 5] = le32dec(key + 4);
+		ctx->state[ 6] = le32dec(key + 8);
+		ctx->state[ 7] = le32dec(key + 12);
+		/* repeat first half of key */
+		ctx->state[ 8] = le32dec(key + 0);
+		ctx->state[ 9] = le32dec(key + 4);
+		ctx->state[10] = le32dec(key + 8);
+		ctx->state[11] = le32dec(key + 12);
+	}
+}
+
+/*
+ * Reset the stream position and load a new nonce.
+ */
+void
+chacha20_reset(chacha20_ctx *ctx, const uint8_t *nonce)
+{
+
+	/* reset stream counter */
+	ctx->state[12] = 0;
+	ctx->state[13] = 0;
+	/* copy nonce */
+	ctx->state[14] = le32dec(nonce + 0);
+	ctx->state[15] = le32dec(nonce + 4);
+}
+
+/*
+ * Encryption: generate a block of keystream, xor it with the plaintext to
+ * produce the ciphertext, and increment the stream position.  If vpt is
+ * NULL, simply copy the requested keystream to the output buffer.
+ */
+size_t
+chacha20_encrypt(chacha20_ctx *ctx, const void *vpt, uint8_t *ct, size_t len)
+{
+	const uint8_t *pt = vpt;
+	uint64_t ctr;
+	uint32_t mix[16];
+	uint8_t ks[64];
+	unsigned int b, i;
+
+	len -= len % sizeof ks;
+	for (b = 0; b < len; b += sizeof ks) {
+		memcpy(mix, ctx->state, sizeof mix);
+		for (i = 0; i < 20; i += 2) {
+			CHACHA_QR(mix,  0,  4,  8, 12);
+			CHACHA_QR(mix,  1,  5,  9, 13);
+			CHACHA_QR(mix,  2,  6, 10, 14);
+			CHACHA_QR(mix,  3,  7, 11, 15);
+			CHACHA_QR(mix,  0,  5, 10, 15);
+			CHACHA_QR(mix,  1,  6, 11, 12);
+			CHACHA_QR(mix,  2,  7,  8, 13);
+			CHACHA_QR(mix,  3,  4,  9, 14);
+		}
+		for (i = 0; i < 16; ++i)
+			le32enc(ks + i * 4, ctx->state[i] + mix[i]);
+		if (pt == NULL) {
+			memcpy(ct, ks, sizeof ks);
+			ct += sizeof ks;
+		} else {
+			for (i = 0; i < 64 && i < len; ++i)
+				*ct++ = *pt++ ^ ks[i];
+		}
+		ctr = le64dec(ctx->state + 12);
+		le64enc(ctx->state + 12, ++ctr);
+	}
+	return (len);
+}
+
+/*
+ * Decryption: identical to encryption.
+ */
+size_t
+chacha20_decrypt(chacha20_ctx *ctx, const uint8_t *ct, void *vpt, size_t len)
+{
+
+	return (chacha20_encrypt(ctx, ct, vpt, len));
+}
+
+/*
+ * Wipe our state.
+ */
+void
+chacha20_finish(chacha20_ctx *ctx)
+{
+
+	memset(ctx, 0, sizeof *ctx);
+}
+
+#ifdef _KERNEL
+
+static int
+chacha20_modevent(module_t mod, int evtype, void *unused)
+{
+
+	switch (evtype) {
+	case MOD_LOAD:
+		return (0);
+	case MOD_UNLOAD:
+		return (0);
+	default:
+		return (EOPNOTSUPP);
+	}
+}
+
+static moduledata_t chacha20_mod = {
+	"chacha20",
+	chacha20_modevent,
+	0
+};
+
+DECLARE_MODULE(chacha20, chacha20_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
+MODULE_VERSION(chacha20, 1);
+#endif

Added: head/sys/crypto/chacha20/chacha20.h
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ head/sys/crypto/chacha20/chacha20.h	Sat Apr 15 20:51:53 2017	(r316982)
@@ -0,0 +1,53 @@
+/*-
+ * Copyright (c) 2017 Dag-Erling Smørgrav
+ * All rights reserved.
+ *
+ * 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, this list of conditions and the following disclaimer.
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 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 ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef SYS_CRYPTO_CHACHA20_H_INCLUDED
+#define SYS_CRYPTO_CHACHA20_H_INCLUDED
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct {
+	uint32_t state[16];
+} chacha20_ctx;
+
+void chacha20_init(chacha20_ctx *, const uint8_t *, size_t);
+void chacha20_reset(chacha20_ctx *, const uint8_t *);
+size_t chacha20_encrypt(chacha20_ctx *, const void *, uint8_t *, size_t);
+size_t chacha20_decrypt(chacha20_ctx *, const uint8_t *, void *, size_t);
+void chacha20_finish(chacha20_ctx *);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

Modified: head/sys/modules/Makefile
==============================================================================
--- head/sys/modules/Makefile	Sat Apr 15 20:37:34 2017	(r316981)
+++ head/sys/modules/Makefile	Sat Apr 15 20:51:53 2017	(r316982)
@@ -73,6 +73,7 @@ SUBDIR=	\
 	cd9660_iconv \
 	${_ce} \
 	${_cfi} \
+	chacha20 \
 	${_chromebook_platform} \
 	${_ciss} \
 	cloudabi \

Added: head/sys/modules/chacha20/Makefile
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ head/sys/modules/chacha20/Makefile	Sat Apr 15 20:51:53 2017	(r316982)
@@ -0,0 +1,8 @@
+# $FreeBSD$
+
+.PATH: ${SRCTOP}/sys/crypto/chacha20
+
+KMOD=	chacha20
+SRCS=	chacha20.c
+
+.include <bsd.kmod.mk>



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