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diff --git a/usr.bin/cksum/cksum.1 b/usr.bin/cksum/cksum.1 new file mode 100644 index 0000000..57c63b1 --- /dev/null +++ b/usr.bin/cksum/cksum.1 @@ -0,0 +1,341 @@ +.\" $NetBSD: cksum.1,v 1.48 2017/07/03 21:34:18 wiz Exp $ +.\" +.\" Copyright (c) 1991, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" This code is derived from software contributed to Berkeley by +.\" the Institute of Electrical and Electronics Engineers, Inc. +.\" +.\" 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. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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. +.\" +.\" @(#)cksum.1 8.2 (Berkeley) 4/28/95 +.\" +.Dd August 31, 2014 +.Dt CKSUM 1 +.Os +.Sh NAME +.Nm cksum , +.Nm md2 , +.Nm md4 , +.Nm md5 , +.Nm rmd160 , +.Nm sha1 , +.Nm sum +.Nd display file checksums and block counts +.Sh SYNOPSIS +.Nm cksum +.Op Fl n +.Op Fl a Ar algorithm Oo Fl pqtx Oc Oo Fl s Ar string Oc +.Op Fl o Ar 1 Ns | Ns Ar 2 +.Op Ar Li \&| Fl c Oo Fl w Oc Oo Ar sumfile Oc +.Nm sum +.Op Fl n +.Op Fl a Ar algorithm Oo Fl pqtx Oc Oo Fl s Ar string Oc +.Op Fl o Ar 1 Ns | Ns Ar 2 +.Op Ar Li \&| Fl c Oo Fl w Oc Oo Ar sumfile Oc +.Nm md2 +.Op Fl npqtx +.Op Fl s Ar string +.Op Ar Li \&| Fl c Oo Fl w Oc Oo Ar sumfile Oc +.Nm md4 +.Op Fl npqtx +.Op Fl s Ar string +.Op Ar Li \&| Fl c Oo Fl w Oc Oo Ar sumfile Oc +.Nm md5 +.Op Fl npqtx +.Op Fl s Ar string +.Op Ar Li \&| Fl c Oo Fl w Oc Oo Ar sumfile Oc +.Nm rmd160 +.Op Fl npqtx +.Op Fl s Ar string +.Op Ar Li \&| Fl c Oo Fl w Oc Oo Ar sumfile Oc +.Nm sha1 +.Op Fl npqtx +.Op Fl s Ar string +.Op Ar Li \&| Fl c Oo Fl w Oc Oo Ar sumfile Oc +.Sh DESCRIPTION +The +.Nm +utility writes to the standard output three whitespace separated +fields for each input file. +These fields are a checksum +.Tn CRC , +the total number of octets in the file and the file name. +If no file name is specified, the standard input is used and no file name +is written. +.Pp +The +.Nm sum +utility is identical to the +.Nm +utility, except that it defaults to using historic algorithm 1, as +described below. +It is provided for compatibility only. +.Pp +The +.Nm md2 , +.Nm md4 , +.Nm md5 , +.Nm sha1 , +and +.Nm rmd160 +utilities compute cryptographic hash functions, and write to standard +output the hexadecimal representation of the hash of their input. +.Pp +The options are as follows: +.Bl -tag -width indent +.It Fl a Ar algorithm +When invoked as +.Nm cksum , +use the specified +.Ar algorithm . +Valid algorithms are: +.Bl -column -offset indent ".Sy Algorithm" ".Sy Bits" ".Sy Description" +.It Sy Algorithm Ta Sy Bits Ta Sy Description +.It Li CRC Ta 32 Ta Default CRC algorithm +.It Li MD2 Ta 128 Ta MD2, per Li RFC1319 +.It Li MD4 Ta 128 Ta MD4, per Li RFC1320 +.It Li MD5 Ta 128 Ta MD5, per Li RFC1321 +.It Li RMD160 Ta 160 Ta RIPEMD-160 +.It Li SHA1 Ta 160 Ta SHA-1, per Li FIPS PUB 180-1 +.It Li SHA256 Ta 256 Ta SHA-2 +.It Li SHA384 Ta 384 Ta SHA-2 +.It Li SHA512 Ta 512 Ta SHA-2 +.It Li old1 Ta 16 Ta Algorithm 1, per Fl o Ar 1 +.It Li old2 Ta 16 Ta Algorithm 2, per Fl o Ar 2 +.El +.It Fl c Op Ar sumfile +Verify (check) files against a list of checksums. +The list is read from +.Ar sumfile , +or from stdin if no filename is given. +E.g. first run +.Dl Ic md5 *.tgz > MD5 +.Dl Ic sha1 *.tgz > SHA1 +to generate a list of MD5 checksums in +.Pa MD5 , +then use the following command to verify them: +.Dl Ic cat MD5 SHA1 | cksum -c +If an error is found during checksum verification, an error +message is printed, and the program returns an error code of 1. +.It Fl o +Use historic algorithms instead of the (superior) default one. +.Pp +Algorithm 1 is the algorithm used by historic +.Bx +systems as the +.Xr sum 1 +algorithm and by historic +.At V +systems as the +.Xr sum 1 +algorithm when using the +.Fl r +option. +This is a 16-bit checksum, with a right rotation before each addition; +overflow is discarded. +.Pp +Algorithm 2 is the algorithm used by historic +.At V +systems as the +default +.Xr sum 1 +algorithm. +This is a 32-bit checksum, and is defined as follows: +.Bd -unfilled -offset indent +s = sum of all bytes; +r = s % 2^16 + (s % 2^32) / 2^16; +cksum = (r % 2^16) + r / 2^16; +.Ed +.Pp +Both algorithm 1 and 2 write to the standard output the same fields as +the default algorithm except that the size of the file in bytes is +replaced with the size of the file in blocks. +For historic reasons, the block size is 1024 for algorithm 1 and 512 +for algorithm 2. +Partial blocks are rounded up. +.It Fl w +Print warnings about malformed checksum files when verifying +checksums with +.Fl c . +.El +.Pp +The following options apply only when using the one of the message +digest algorithms: +.Bl -tag -width indent +.It Fl n +Print the hash and the filename in the normal sum output form, with +the hash at the left and the filename following on the right. +.It Fl p +Echo input from standard input to standard output, and append the +selected message digest. +.It Fl q +Quiet mode \(em only the checksum is printed out. +Overrides the +.Fl n +option. +.It Fl s Ar string +Print the hash of the given string +.Ar string . +.It Fl t +Run a built-in message digest time trial. +.It Fl x +Run a built-in message digest test script. +The tests that are run +are supposed to encompass all the various tests in the suites that +accompany the algorithms' descriptions with the exception of the +last test for the SHA-1 algorithm and the RIPEMD-160 algorithm. +The +last test for these is one million copies of the lower letter a. +.El +.Pp +The default +.Tn CRC +used is based on the polynomial used for +.Tn CRC +error checking +in the networking standard +.St -iso8802-3 . +The +.Tn CRC +checksum encoding is defined by the generating polynomial: +.Pp +.Bd -unfilled -offset indent +G(x) = x^32 + x^26 + x^23 + x^22 + x^16 + x^12 + + x^11 + x^10 + x^8 + x^7 + x^5 + x^4 + x^2 + x + 1 +.Ed +.Pp +Mathematically, the +.Tn CRC +value corresponding to a given file is defined by +the following procedure: +.Bd -filled -offset indent +The +.Ar n +bits to be evaluated are considered to be the coefficients of a mod 2 +polynomial M(x) of degree +.Ar n Ns \-1 . +These +.Ar n +bits are the bits from the file, with the most significant bit being the most +significant bit of the first octet of the file and the last bit being the least +significant bit of the last octet, padded with zero bits (if necessary) to +achieve an integral number of octets, followed by one or more octets +representing the length of the file as a binary value, least significant octet +first. +The smallest number of octets capable of representing this integer are used. +.Pp +M(x) is multiplied by x^32 (i.e., shifted left 32 bits) and divided by +G(x) using mod 2 division, producing a remainder R(x) of degree \*[Le] 31. +.Pp +The coefficients of R(x) are considered to be a 32-bit sequence. +.Pp +The bit sequence is complemented and the result is the CRC. +.Ed +.Pp +The +.Nm +and +.Nm sum +utilities exit 0 on success, and >0 if an error occurs. +.Sh SEE ALSO +.Xr openssl 1 , +.Xr mtree 8 +.Pp +The default calculation is identical to that given in pseudo-code +in the following +.Tn ACM +article. +.Rs +.%T "Computation of Cyclic Redundancy Checks Via Table Lookup" +.%A Dilip V. Sarwate +.%J "Communications of the ACM" +.%D "August 1988" +.Re +.Rs +.%A R. Rivest +.%T The MD2 Message-Digest Algorithm +.%O RFC 1319 +.Re +.Rs +.%A R. Rivest +.%T The MD4 Message-Digest Algorithm +.%O RFC 1186 and RFC 1320 +.Re +.Rs +.%A R. Rivest +.%T The MD5 Message-Digest Algorithm +.%O RFC 1321 +.Re +.Rs +.%A U.S. DOC/NIST +.%T Secure Hash Standard +.%O FIPS PUB 180-1 +.Re +.Sh STANDARDS +The +.Nm +utility is expected to conform to +.St -p1003.1-2004 . +.Sh HISTORY +The +.Nm +utility appeared in +.Bx 4.4 . +.Nm md5 +was added in +.Nx 1.3 . +The functionality for +.Nm md2 , +.Nm md4 , +.Nm sha1 , +and +.Nm rmd160 +was added in +.Nx 1.6 . +Support for the SHA-2 algorithms +.Po +.Li SHA256 , +.Li SHA384 , +and +.Li SHA512 +.Pc +was added in +.Nx 3.0 . +The functionality to verify checksum stored in a file +.Pq Fl c +first appeared in +.Nx 4.0 . +Quiet mode +.Pq Fl q +was added in +.Nx 7.0 . +.\" .Pp +.\" The +.\" .Nm sum +.\" utility appeared in +.\" .Bx ?.? +.\" and +.\" .At V . |