Import the skein hashing algorithm, based on the threefish block cipher

Connect it to userland (libmd, libcrypt, sbin/md5) and kernel (crypto.ko)

Support for skein as a ZFS checksum algorithm was introduced in r289422
but is disconnected because FreeBSD lacked a Skein implementation.

A further commit will enable it in ZFS.

Reviewed by:	cem
Sponsored by:	ScaleEngine Inc.
Differential Revision:	https://reviews.freebsd.org/D6166

8 files changed, 409 insertions, 15 deletions

diff --git a/lib/libmd/Makefile b/lib/libmd/Makefile
index 111a9f4..bb50623 100644
--- a/lib/libmd/Makefile
+++ b/lib/libmd/Makefile
@@ -9,12 +9,15 @@ SRCS=	md4c.c md5c.c md4hl.c md5hl.c \
 	sha0c.c sha0hl.c sha1c.c sha1hl.c \
 	sha256c.c sha256hl.c \
 	sha384hl.c \
-	sha512c.c sha512hl.c sha512thl.c
-INCS=	md4.h md5.h ripemd.h sha.h sha256.h sha384.h sha512.h sha512t.h
+	sha512c.c sha512hl.c sha512thl.c \
+	skein.c skein_block.c \
+	skein256hl.c skein512hl.c skein1024hl.c
+INCS=	md4.h md5.h ripemd.h sha.h sha256.h sha384.h sha512.h sha512t.h \
+	skein.h skein_port.h skein_freebsd.h skein_iv.h
 
 WARNS?=	0
 
-MAN+=	md4.3 md5.3 ripemd.3 sha.3 sha256.3 sha512.3
+MAN+=	md4.3 md5.3 ripemd.3 sha.3 sha256.3 sha512.3 skein.3
 MLINKS+=md4.3 MD4Init.3 md4.3 MD4Update.3 md4.3 MD4Final.3
 MLINKS+=md4.3 MD4End.3  md4.3 MD4File.3   md4.3 MD4FileChunk.3
 MLINKS+=md4.3 MD4Data.3
@@ -47,11 +50,27 @@ MLINKS+=sha512.3 SHA512_256_Init.3  sha512.3 SHA512_256_Update.3
 MLINKS+=sha512.3 SHA512_256_Final.3 sha512.3 SHA512_256_End.3
 MLINKS+=sha512.3 SHA512_256_File.3  sha512.3 SHA512_256_FileChunk.3
 MLINKS+=sha512.3 SHA512_256_Data.3
+MLINKS+=skein.3 SKEIN256_Init.3  skein.3 SKEIN256_Update.3
+MLINKS+=skein.3 SKEIN256_Final.3 skein.3 SKEIN256_End.3
+MLINKS+=skein.3 SKEIN256_File.3  skein.3 SKEIN256_FileChunk.3
+MLINKS+=skein.3 SKEIN256_Data.3  skein.3 skein256.3
+MLINKS+=skein.3 SKEIN512_Init.3  skein.3 SKEIN512_Update.3
+MLINKS+=skein.3 SKEIN512_Final.3 skein.3 SKEIN512_End.3
+MLINKS+=skein.3 SKEIN512_File.3  skein.3 SKEIN512_FileChunk.3
+MLINKS+=skein.3 SKEIN512_Data.3  skein.3 skein512.3
+MLINKS+=skein.3 SKEIN1024_Init.3  skein.3 SKEIN1024_Update.3
+MLINKS+=skein.3 SKEIN1024_Final.3 skein.3 SKEIN1024_End.3
+MLINKS+=skein.3 SKEIN1024_File.3  skein.3 SKEIN1024_FileChunk.3
+MLINKS+=skein.3 SKEIN1024_Data.3  skein.3 skein1024.3
+
 CLEANFILES+=	md[245]hl.c md[245].ref md[245].3 mddriver \
 		rmd160.ref rmd160hl.c rmddriver \
 		sha0.ref sha0hl.c sha1.ref sha1hl.c shadriver \
 		sha256.ref sha256hl.c sha384hl.c sha384.ref \
-		sha512.ref sha512hl.c sha512t256.ref sha512thl.c
+		sha512.ref sha512hl.c sha512t256.ref sha512thl.c \
+		skein256hl.c skein512hl.c skein1024hl.c \
+		skein256.ref skein512.ref skein1024.ref \
+		skeindriver
 
 # Define WEAK_REFS to provide weak aliases for libmd symbols
 #
@@ -60,8 +79,10 @@ CLEANFILES+=	md[245]hl.c md[245].ref md[245].3 mddriver \
 #   * macros are used to rename symbols to libcrypt internal names
 #   * no weak aliases are generated
 CFLAGS+= -I${.CURDIR} -I${.CURDIR}/../../sys/crypto/sha2
+CFLAGS+= -I${.CURDIR}/../../sys/crypto/skein
 CFLAGS+= -DWEAK_REFS
 .PATH: ${.CURDIR}/${MACHINE_ARCH} ${.CURDIR}/../../sys/crypto/sha2
+.PATH: ${.CURDIR}/../../sys/crypto/skein ${.CURDIR}/../../sys/crypto/skein/${MACHINE_ARCH}
 
 .if exists(${MACHINE_ARCH}/sha.S)
 SRCS+=	sha.S
@@ -71,7 +92,11 @@ CFLAGS+= -DSHA1_ASM
 SRCS+=	rmd160.S
 CFLAGS+= -DRMD160_ASM
 .endif
-.if exists(${MACHINE_ARCH}/sha.S) || exists(${MACHINE_ARCH}/rmd160.S)
+.if exists(${MACHINE_ARCH}/skein_block_asm.s)
+SRCS+= skein_block_asm.s
+CFLAGS+= -DSKEIN_ASM -DSKEIN_USE_ASM=1792 # list of block functions to replace with assembly: 256+512+1024 = 1792
+.endif
+.if exists(${MACHINE_ARCH}/sha.S) || exists(${MACHINE_ARCH}/rmd160.S) || exists(${MACHINE_ARCH}/skein_block_asm.s)
 ACFLAGS+= -DELF -Wa,--noexecstack
 .endif
 
@@ -124,6 +149,25 @@ rmd160hl.c: mdXhl.c
 			-e 's/RIPEMD160__/RIPEMD160_/g' \
 			${.ALLSRC}) > ${.TARGET}
 
+skein256hl.c: mdXhl.c
+	(echo '#define LENGTH 32'; \
+		sed -e 's/mdX/skein/g' -e 's/MDX/SKEIN256_/g'	\
+			-e  's/SKEIN256__/SKEIN256_/g' \
+		${.ALLSRC}) > ${.TARGET}
+
+skein512hl.c: mdXhl.c
+	(echo '#define LENGTH 64'; \
+		sed -e 's/mdX/skein/g' -e 's/MDX/SKEIN512_/g'	\
+			-e  's/SKEIN512__/SKEIN512_/g' \
+		${.ALLSRC}) > ${.TARGET}
+
+skein1024hl.c: mdXhl.c
+	(echo '#define LENGTH 128'; \
+		sed -e 's/mdX/skein/g' -e 's/MDX/SKEIN1024_/g'	\
+			-e  's/SKEIN1024__/SKEIN1024_/g' \
+		${.ALLSRC}) > ${.TARGET}
+
+
 .for i in 2 4 5
 md${i}.3: ${.CURDIR}/mdX.3
 	sed -e "s/mdX/md${i}/g" -e "s/MDX/MD${i}/g" ${.ALLSRC} > ${.TARGET}
@@ -250,8 +294,51 @@ rmd160.ref:
 	@echo 'RIPEMD160 ("12345678901234567890123456789012345678901234567890123456789012345678901234567890") =' \
 		'9b752e45573d4b39f4dbd3323cab82bf63326bfb' >> ${.TARGET}
 
+skein256.ref:
+	echo 'SKEIN256 test suite:' > ${.TARGET}
+	@echo 'SKEIN256 ("") = c8877087da56e072870daa843f176e9453115929094c3a40c463a196c29bf7ba' >> ${.TARGET}
+	@echo 'SKEIN256 ("abc") = 258bdec343b9fde1639221a5ae0144a96e552e5288753c5fec76c05fc2fc1870' >> ${.TARGET}
+	@echo 'SKEIN256 ("message digest") =' \
+		'4d2ce0062b5eb3a4db95bc1117dd8aa014f6cd50fdc8e64f31f7d41f9231e488' >> ${.TARGET}
+	@echo 'SKEIN256 ("abcdefghijklmnopqrstuvwxyz") =' \
+		'46d8440685461b00e3ddb891b2ecc6855287d2bd8834a95fb1c1708b00ea5e82' >> ${.TARGET}
+	@echo 'SKEIN256 ("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789") =' \
+		'7c5eb606389556b33d34eb2536459528dc0af97adbcd0ce273aeb650f598d4b2' >> ${.TARGET}
+	@echo 'SKEIN256 ("12345678901234567890123456789012345678901234567890123456789012345678901234567890") =' \
+		'4def7a7e5464a140ae9c3a80279fbebce4bd00f9faad819ab7e001512f67a10d' >> ${.TARGET}
+
+skein512.ref:
+	echo 'SKEIN512 test suite:' > ${.TARGET}
+	@echo 'SKEIN512 ("") =' \
+		'bc5b4c50925519c290cc634277ae3d6257212395cba733bbad37a4af0fa06af41fca7903d06564fea7a2d3730dbdb80c1f85562dfcc070334ea4d1d9e72cba7a' >> ${.TARGET}
+	@echo 'SKEIN512 ("abc") =' \
+		'8f5dd9ec798152668e35129496b029a960c9a9b88662f7f9482f110b31f9f93893ecfb25c009baad9e46737197d5630379816a886aa05526d3a70df272d96e75' >> ${.TARGET}
+	@echo 'SKEIN512 ("message digest") =' \
+		'15b73c158ffb875fed4d72801ded0794c720b121c0c78edf45f900937e6933d9e21a3a984206933d504b5dbb2368000411477ee1b204c986068df77886542fcc' >> ${.TARGET}
+	@echo 'SKEIN512 ("abcdefghijklmnopqrstuvwxyz") =' \
+		'23793ad900ef12f9165c8080da6fdfd2c8354a2929b8aadf83aa82a3c6470342f57cf8c035ec0d97429b626c4d94f28632c8f5134fd367dca5cf293d2ec13f8c' >> ${.TARGET}
+	@echo 'SKEIN512 ("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789") =' \
+		'0c6bed927e022f5ddcf81877d42e5f75798a9f8fd3ede3d83baac0a2f364b082e036c11af35fe478745459dd8f5c0b73efe3c56ba5bb2009208d5a29cc6e469c' >> ${.TARGET}
+	@echo 'SKEIN512 ("12345678901234567890123456789012345678901234567890123456789012345678901234567890") =' \
+		'2ca9fcffb3456f297d1b5f407014ecb856f0baac8eb540f534b1f187196f21e88f31103128c2f03fcc9857d7a58eb66f9525e2302d88833ee069295537a434ce' >> ${.TARGET}
+
+skein1024.ref:
+	echo 'SKEIN1024 test suite:' > ${.TARGET}
+	@echo 'SKEIN1024 ("") =' \
+		'0fff9563bb3279289227ac77d319b6fff8d7e9f09da1247b72a0a265cd6d2a62645ad547ed8193db48cff847c06494a03f55666d3b47eb4c20456c9373c86297d630d5578ebd34cb40991578f9f52b18003efa35d3da6553ff35db91b81ab890bec1b189b7f52cb2a783ebb7d823d725b0b4a71f6824e88f68f982eefc6d19c6' >> ${.TARGET}
+	@echo 'SKEIN1024 ("abc") =' \
+		'35a599a0f91abcdb4cb73c19b8cb8d947742d82c309137a7caed29e8e0a2ca7a9ff9a90c34c1908cc7e7fd99bb15032fb86e76df21b72628399b5f7c3cc209d7bb31c99cd4e19465622a049afbb87c03b5ce3888d17e6e667279ec0aa9b3e2712624c01b5f5bbe1a564220bdcf6990af0c2539019f313fdd7406cca3892a1f1f' >> ${.TARGET}
+	@echo 'SKEIN1024 ("message digest") =' \
+		'ea891f5268acd0fac97467fc1aa89d1ce8681a9992a42540e53babee861483110c2d16f49e73bac27653ff173003e40cfb08516cd34262e6af95a5d8645c9c1abb3e813604d508b8511b30f9a5c1b352aa0791c7d2f27b2706dccea54bc7de6555b5202351751c3299f97c09cf89c40f67187e2521c0fad82b30edbb224f0458' >> ${.TARGET}
+	@echo 'SKEIN1024 ("abcdefghijklmnopqrstuvwxyz") =' \
+		'f23d95c2a25fbcd0e797cd058fec39d3c52d2b5afd7a9af1df934e63257d1d3dcf3246e7329c0f1104c1e51e3d22e300507b0c3b9f985bb1f645ef49835080536becf83788e17fed09c9982ba65c3cb7ffe6a5f745b911c506962adf226e435c42f6f6bc08d288f9c810e807e3216ef444f3db22744441deefa4900982a1371f' >> ${.TARGET}
+	@echo 'SKEIN1024 ("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789") =' \
+		'cf3889e8a8d11bfd3938055d7d061437962bc5eac8ae83b1b71c94be201b8cf657fdbfc38674997a008c0c903f56a23feb3ae30e012377f1cfa080a9ca7fe8b96138662653fb3335c7d06595bf8baf65e215307532094cfdfa056bd8052ab792a3944a2adaa47b30335b8badb8fe9eb94fe329cdca04e58bbc530f0af709f469' >> ${.TARGET}
+	@echo 'SKEIN1024 ("12345678901234567890123456789012345678901234567890123456789012345678901234567890") =' \
+		'cf21a613620e6c119eca31fdfaad449a8e02f95ca256c21d2a105f8e4157048f9fe1e897893ea18b64e0e37cb07d5ac947f27ba544caf7cbc1ad094e675aed77a366270f7eb7f46543bccfa61c526fd628408058ed00ed566ac35a9761d002e629c4fb0d430b2f4ad016fcc49c44d2981c4002da0eecc42144160e2eaea4855a' >> ${.TARGET}
+
 test:	md4.ref md5.ref sha0.ref rmd160.ref sha1.ref sha256.ref sha384.ref \
-		sha512.ref sha512t256.ref
+		sha512.ref sha512t256.ref skein256.ref skein512.ref skein1024.ref
 	@${ECHO} if any of these test fail, the code produces wrong results
 	@${ECHO} and should NOT be used.
 	${CC} ${CFLAGS} ${LDFLAGS} -DMD=4 -o mddriver ${.CURDIR}/mddriver.c libmd.a
@@ -284,5 +371,15 @@ test:	md4.ref md5.ref sha0.ref rmd160.ref sha1.ref sha256.ref sha384.ref \
 	./shadriver | cmp sha512t256.ref -
 	@${ECHO} SHA-512t256 passed test
 	-rm -f shadriver
+	${CC} ${CFLAGS} ${LDFLAGS} -DSKEIN=256 -o skeindriver ${.CURDIR}/skeindriver.c libmd.a
+	./skeindriver | cmp skein256.ref -
+	@${ECHO} SKEIN256 passed test
+	${CC} ${CFLAGS} ${LDFLAGS} -DSKEIN=512 -o skeindriver ${.CURDIR}/skeindriver.c libmd.a
+	./skeindriver | cmp skein512.ref -
+	@${ECHO} SKEIN512 passed test
+	${CC} ${CFLAGS} ${LDFLAGS} -DSKEIN=1024 -o skeindriver ${.CURDIR}/skeindriver.c libmd.a
+	./skeindriver | cmp skein1024.ref -
+	@${ECHO} SKEIN1024 passed test
+	-rm -f skeindriver
 
 .include <bsd.lib.mk>
diff --git a/lib/libmd/mdX.3 b/lib/libmd/mdX.3
index 4cc321f..daa5c36 100644
--- a/lib/libmd/mdX.3
+++ b/lib/libmd/mdX.3
@@ -8,7 +8,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd February 11, 1999
+.Dd April 26, 2016
 .Dt MDX 3
 .Os
 .Sh NAME
@@ -145,7 +145,11 @@ argument is non-null it must point to at least 33 characters of buffer space.
 .Sh SEE ALSO
 .Xr md4 3 ,
 .Xr md5 3 ,
-.Xr sha 3
+.Xr ripemd 3 ,
+.Xr sha 3 ,
+.Xr sha256 3 ,
+.Xr sha512 3 ,
+.Xr skein 3
 .Rs
 .%A R. Rivest
 .%T The MD4 Message-Digest Algorithm
diff --git a/lib/libmd/ripemd.3 b/lib/libmd/ripemd.3
index 2c9d2d3..8e868b8 100644
--- a/lib/libmd/ripemd.3
+++ b/lib/libmd/ripemd.3
@@ -9,7 +9,7 @@
 .\" 	From: Id: mdX.3,v 1.14 1999/02/11 20:31:49 wollman Exp
 .\" $FreeBSD$
 .\"
-.Dd March 28, 2014
+.Dd April 26, 2016
 .Dt RIPEMD 3
 .Os
 .Sh NAME
@@ -125,7 +125,10 @@ argument is non-null it must point to at least 41 characters of buffer space.
 .Sh SEE ALSO
 .Xr md4 3 ,
 .Xr md5 3 ,
-.Xr sha 3
+.Xr sha 3 ,
+.Xr sha256 3 ,
+.Xr sha512 3 ,
+.Xr skein 3
 .Sh HISTORY
 These functions appeared in
 .Fx 4.0 .
diff --git a/lib/libmd/sha.3 b/lib/libmd/sha.3
index fe5c339..95c0603 100644
--- a/lib/libmd/sha.3
+++ b/lib/libmd/sha.3
@@ -9,7 +9,7 @@
 .\" 	From: Id: mdX.3,v 1.14 1999/02/11 20:31:49 wollman Exp
 .\" $FreeBSD$
 .\"
-.Dd March 28, 2014
+.Dd April 26, 2016
 .Dt SHA 3
 .Os
 .Sh NAME
@@ -157,7 +157,9 @@ argument is non-null it must point to at least 41 characters of buffer space.
 .Xr md4 3 ,
 .Xr md5 3 ,
 .Xr ripemd 3 ,
-.Xr sha256 3
+.Xr sha256 3 ,
+.Xr sha512 3 ,
+.Xr skein 3
 .Sh HISTORY
 These functions appeared in
 .Fx 4.0 .
diff --git a/lib/libmd/sha256.3 b/lib/libmd/sha256.3
index 6117e70..530c644 100644
--- a/lib/libmd/sha256.3
+++ b/lib/libmd/sha256.3
@@ -9,7 +9,7 @@
 .\" 	From: Id: mdX.3,v 1.14 1999/02/11 20:31:49 wollman Exp
 .\" $FreeBSD$
 .\"
-.Dd March 28, 2014
+.Dd April 26, 2016
 .Dt SHA256 3
 .Os
 .Sh NAME
@@ -123,7 +123,10 @@ argument is non-null it must point to at least 65 characters of buffer space.
 .Xr md4 3 ,
 .Xr md5 3 ,
 .Xr ripemd 3 ,
-.Xr sha 3
+.Xr sha 3 ,
+.Xr sha256 3 ,
+.Xr sha512 3 ,
+.Xr skein 3
 .Sh HISTORY
 These functions appeared in
 .Fx 6.0 .
diff --git a/lib/libmd/sha512.3 b/lib/libmd/sha512.3
index 2eb5850..d718ada 100644
--- a/lib/libmd/sha512.3
+++ b/lib/libmd/sha512.3
@@ -192,7 +192,10 @@ string which represents the 256 bits in hexadecimal.
 .Xr md4 3 ,
 .Xr md5 3 ,
 .Xr ripemd 3 ,
-.Xr sha 3
+.Xr sha 3 ,
+.Xr sha256 3 ,
+.Xr sha512 3 ,
+.Xr skein 3
 .Sh HISTORY
 These functions appeared in
 .Fx 9.0 .
diff --git a/lib/libmd/skein.3 b/lib/libmd/skein.3
new file mode 100644
index 0000000..11c78a7
--- /dev/null
+++ b/lib/libmd/skein.3
@@ -0,0 +1,214 @@
+.\"-
+.\" Copyright (c) 2016 Allan Jude
+.\" 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.
+.\"
+.\" 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.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd May 28, 2016
+.Dt SKEIN 3
+.Os
+.Sh NAME
+.Nm SKEIN256_Init ,
+.Nm SKEIN256_Update ,
+.Nm SKEIN256_Final ,
+.Nm SKEIN256_End ,
+.Nm SKEIN256_File ,
+.Nm SKEIN256_FileChunk ,
+.Nm SKEIN256_Data ,
+.Nm SKEIN512_Init ,
+.Nm SKEIN512_Update ,
+.Nm SKEIN512_Final ,
+.Nm SKEIN512_End ,
+.Nm SKEIN512_File ,
+.Nm SKEIN512_FileChunk ,
+.Nm SKEIN512_Data ,
+.Nm SKEIN1024_Init ,
+.Nm SKEIN1024_Update ,
+.Nm SKEIN1024_Final ,
+.Nm SKEIN1024_End ,
+.Nm SKEIN1024_File ,
+.Nm SKEIN1024_FileChunk ,
+.Nm SKEIN1024_Data
+.Nd calculate the ``SKEIN'' family of message digests
+.Sh LIBRARY
+.Lb libmd
+.Sh SYNOPSIS
+.In sys/types.h
+.In skein.h
+.Ft void
+.Fn SKEIN256_Init "SKEIN256_CTX *context"
+.Ft void
+.Fn SKEIN256_Update "SKEIN256_CTX *context" "const unsigned char *data" "size_t len"
+.Ft void
+.Fn SKEIN256_Final "unsigned char digest[32]" "SKEIN256_CTX *context"
+.Ft "char *"
+.Fn SKEIN256_End "SKEIN256_CTX *context" "char *buf"
+.Ft "char *"
+.Fn SKEIN256_File "const char *filename" "char *buf"
+.Ft "char *"
+.Fn SKEIN256_FileChunk "const char *filename" "char *buf" "off_t offset" "off_t length"
+.Ft "char *"
+.Fn SKEIN256_Data "const unsigned char *data" "unsigned int len" "char *buf"
+.Ft void
+.Fn SKEIN512_Init "SKEIN512_CTX *context"
+.Ft void
+.Fn SKEIN512_Update "SKEIN512_CTX *context" "const unsigned char *data" "size_t len"
+.Ft void
+.Fn SKEIN512_Final "unsigned char digest[64]" "SKEIN512_CTX *context"
+.Ft "char *"
+.Fn SKEIN512_End "SKEIN512_CTX *context" "char *buf"
+.Ft "char *"
+.Fn SKEIN512_File "const char *filename" "char *buf"
+.Ft "char *"
+.Fn SKEIN512_FileChunk "const char *filename" "char *buf" "off_t offset" "off_t length"
+.Ft "char *"
+.Fn SKEIN512_Data "const unsigned char *data" "unsigned int len" "char *buf"
+.Ft void
+.Fn SKEIN1024_Init "SKEIN1024_CTX *context"
+.Ft void
+.Fn SKEIN1024_Update "SKEIN1024_CTX *context" "const unsigned char *data" "size_t len"
+.Ft void
+.Fn SKEIN1024_Final "unsigned char digest[128]" "SKEIN1024_CTX *context"
+.Ft "char *"
+.Fn SKEIN1024_End "SKEIN1024_CTX *context" "char *buf"
+.Ft "char *"
+.Fn SKEIN1024_File "const char *filename" "char *buf"
+.Ft "char *"
+.Fn SKEIN1024_FileChunk "const char *filename" "char *buf" "off_t offset" "off_t length"
+.Ft "char *"
+.Fn SKEIN1024_Data "const unsigned char *data" "unsigned int len" "char *buf"
+.Sh DESCRIPTION
+.Li Skein
+is a new family of cryptographic hash functions based on the
+.Li Threefish
+large-block cipher.
+Its design combines speed, security, simplicity, and a great deal of
+flexibility in a modular package that is easy to analyze.
+.Li Skein
+is defined for three different internal state sizes\(em256 bits, 512 bits, and
+1024 bits\(emand any output size.
+This allows Skein to be a drop-in replacement for the entire SHA family
+of hash functions.
+.Pp
+The
+.Fn SKEIN256_Init ,
+.Fn SKEIN256_Update ,
+and
+.Fn SKEIN256_Final
+functions are the core functions.
+Allocate an
+.Vt SKEIN256_CTX ,
+initialize it with
+.Fn SKEIN256_Init ,
+run over the data with
+.Fn SKEIN256_Update ,
+and finally extract the result using
+.Fn SKEIN256_Final .
+.Pp
+.Fn SKEIN256_End
+is a wrapper for
+.Fn SKEIN256_Final
+which converts the return value to a 33-character
+(including the terminating '\e0')
+.Tn ASCII
+string which represents the 256 bits in hexadecimal.
+.Pp
+.Fn SKEIN256_File
+calculates the digest of a file, and uses
+.Fn SKEIN256_End
+to return the result.
+If the file cannot be opened, a null pointer is returned.
+.Fn SKEIN256_FileChunk
+is similar to
+.Fn SKEIN256_File ,
+but it only calculates the digest over a byte-range of the file specified,
+starting at
+.Fa offset
+and spanning
+.Fa length
+bytes.
+If the
+.Fa length
+parameter is specified as 0, or more than the length of the remaining part
+of the file,
+.Fn SKEIN256_FileChunk
+calculates the digest from
+.Fa offset
+to the end of file.
+.Fn SKEIN256_Data
+calculates the digest of a chunk of data in memory, and uses
+.Fn SKEIN256_End
+to return the result.
+.Pp
+When using
+.Fn SKEIN256_End ,
+.Fn SKEIN256_File ,
+or
+.Fn SKEIN256_Data ,
+the
+.Fa buf
+argument can be a null pointer, in which case the returned string
+is allocated with
+.Xr malloc 3
+and subsequently must be explicitly deallocated using
+.Xr free 3
+after use.
+If the
+.Fa buf
+argument is non-null it must point to at least 33 characters of buffer space.
+.Pp
+The
+.Li SKEIN512_
+and
+.Li SKEIN1024_
+functions are similar to the
+.Li SKEIN256_
+functions except they produce a 512-bit, 65 character,
+or 1024-bit, 129 character, output.
+.Sh SEE ALSO
+.Xr md4 3 ,
+.Xr md5 3 ,
+.Xr ripemd 3 ,
+.Xr sha 3 ,
+.Xr sha256 3 ,
+.Xr sha512 3
+.Sh HISTORY
+These functions appeared in
+.Fx 11.0 .
+.Sh AUTHORS
+.An -nosplit
+The core hash routines were imported from version 1.3 of the optimized 
+Skein reference implementation written by
+.An Doug Whiting
+as submitted to the NSA SHA-3 contest.
+The algorithms were developed by
+.An Niels Ferguson , 
+.An Stefan Lucks ,
+.An Bruce Schneier , 
+.An Doug Whiting , 
+.An Mihir Bellare ,
+.An Tadayoshi Kohno ,
+.An Jon Callas,
+and
+.An Jesse Walker .
diff --git a/lib/libmd/skeindriver.c b/lib/libmd/skeindriver.c
new file mode 100644
index 0000000..5960457
--- /dev/null
+++ b/lib/libmd/skeindriver.c
@@ -0,0 +1,68 @@
+/* SKEINDRIVER.C - test driver for SKEIN */
+
+/* Copyright (C) 1990-2, RSA Data Security, Inc. Created 1990. All rights
+ * reserved.
+ * 
+ * RSA Data Security, Inc. makes no representations concerning either the
+ * merchantability of this software or the suitability of this software for
+ * any particular purpose. It is provided "as is" without express or implied
+ * warranty of any kind.
+ * 
+ * These notices must be retained in any copies of any part of this
+ * documentation and/or software. */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+
+#include <stdio.h>
+#include <time.h>
+#include <string.h>
+
+#include "skein.h"
+
+/* The following makes SKEIN default to SKEIN512 if it has not already been
+ * defined with C compiler flags. */
+#ifndef SKEIN
+#define SKEIN 512
+#endif
+
+#if SKEIN == 256
+#undef SKEIN_Data
+#define SKEIN_Data SKEIN256_Data
+#elif SKEIN == 512
+#undef SKEIN_Data
+#define SKEIN_Data SKEIN512_Data
+#elif SKEIN == 1024
+#undef SKEIN_Data
+#define SKEIN_Data SKEIN1024_Data
+#endif
+
+/* Digests a string and prints the result. */
+static void
+SKEINString(char *string)
+{
+	char buf[2*128 + 1];
+
+	printf("SKEIN%d (\"%s\") = %s\n",
+	       SKEIN, string, SKEIN_Data(string, strlen(string), buf));
+}
+
+/* Digests a reference suite of strings and prints the results. */
+int
+main(void)
+{
+	printf("SKEIN%d test suite:\n", SKEIN);
+
+	SKEINString("");
+	SKEINString("abc");
+	SKEINString("message digest");
+	SKEINString("abcdefghijklmnopqrstuvwxyz");
+	SKEINString("ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+		  "abcdefghijklmnopqrstuvwxyz0123456789");
+	SKEINString("1234567890123456789012345678901234567890"
+		  "1234567890123456789012345678901234567890");
+
+	return 0;
+}