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MD5(1)			     General Commands Manual			  MD5(1)

NAME
     md5,  sha1,  sha224,  sha256,  sha384,  sha512, md5sum, sha1sum, sha224sum,
     sha256sum, sha384sum, sha512sum -- calculate a  message-digest  fingerprint
     (checksum) for a file

SYNOPSIS
     md5 [-pqrtx] [-c string] [-s string] [file ...]

     md5sum [-bctwz] [--binary] [--check] [--help] [--ignore-missing] [--quiet]
	 [--status] [--strict] [--tag] [--text] [--version] [--warn] [--zero]
	 [file ...]

	 (All other hashes have the same options and usage.)

     shasum [-0bchqstUvw] [--01] [-a | --algorithm alg] [--binary] [--check]
	 [--help] [--ignore-missing] [--quiet] [--status] [--strict] [--tag]
	 [--text] [--UNIVERSAL] [--version] [--warn] [file ...]

DESCRIPTION
     The md5, sha1, sha224, sha256, sha384, and sha512 utilities take as input a
     message  of  arbitrary  length  and  produce  as  output a "fingerprint" or
     "message digest" of the input.

     The md5sum, sha1sum, sha224sum, sha256sum, sha384sum, and sha512sum  utili-
     ties  do  the same, but with command-line options and an output format that
     match those of their similary named GNU utilities.

     In all cases, each file listed on the command line is processed separately.
     If no files are listed on the command line, or a file name is given  as  -,
     input is taken from stdin instead.

     It is conjectured that it is computationally infeasible to produce two mes-
     sages  having  the  same message digest, or to produce any message having a
     given prespecified target message digest.	The SHA-224,  SHA-256,	SHA-384,
     and  SHA-512  algorithms  are  intended for digital signature applications,
     where a large file must be "compressed" in a secure manner before being en-
     crypted with a private (secret) key under a public-key cryptosystem such as
     RSA.

     The MD5 and SHA-1 algorithms have been proven to be vulnerable to practical
     collision attacks and should not be relied upon to produce unique	outputs,
     nor  should they be used as part of a cryptographic signature scheme. As of
     2017-03-02, there is no publicly known method to reverse either  algorithm,
     i.e., to find an input that produces a specific output.

     It  is  recommended that all new applications use SHA-512 instead of one of
     the other hash functions.

   BSD OPTIONS
     The following options are available in BSD mode, i.e. when the  program  is
     invoked with a name that does not end in "sum":

     -c string, --check=string
	     Compare  the  digest  of the file against this string.  If combined
	     with the -q or --quiet option, the calculated digest is printed  in
	     addition  to  the exit status being set.  (Note that this option is
	     not yet useful if multiple files are specified.)

     -p, --passthrough
	     Echo stdin to stdout and append the checksum to  stdout.	In  this
	     mode, any files specified on the command line are silently ignored.

     -q, --quiet
	     Quiet  mode  -- only the checksum is printed out.	Overrides the -r
	     or --reverse option.

     -r, --reverse
	     Reverses the format of the output.  This helps with  visual  diffs.
	     Does nothing when combined with the -ptx options.

     -s string, --string=string
	     Print  a  checksum  of  the  given string.  In this mode, any files
	     specified on the command line are silently ignored.

     -t, --time-trial
	     Run a built-in time trial.  For the -sum versions, this  is  a  nop
	     for compatibility with coreutils.

     -x, --self-test
	     Run a built-in test script.

   GNU OPTIONS
     The  following  options are available in GNU mode, i.e. when the program is
     invoked with a name that ends in "sum":

     -b, --binary
	     Read files in binary mode.

     -c, --check
	     The file passed as arguments must contain digest lines generated by
	     the same digest algorithm in either classical BSD format or in  GNU
	     coreutils	format.   A  line with the file name followed by a colon
	     "": and either OK or FAILED is written for each well-formed line in
	     the digest file.  If applicable, the number of  failed  comparisons
	     and the number of lines that were skipped since they were not well-
	     formed  are  printed at the end.  The --quiet option can be used to
	     quiesce the output unless there are mismatched entries in	the  di-
	     gest.

     --help  Print a usage message and exit.

     --ignore-missing
	     When  verifying  checksums,  ignore  files  for which checksums are
	     given but which aren't found on disk.

     --quiet
	     When verifying checksums, do not print anything unless the  verifi-
	     cation fails.

     --status
	     When  verifying  checksums, do not print anything at all.	The exit
	     code will reflect whether verification succeeded.

     --strict
	     When verifying checksums, fail if the input is malformed.

     --tag   Produce BSD-style output.

     -t, --text
	     Read files in text mode.  This is the default.  Note that this  im-
	     plementation does not differentiate between binary and text mode.

     --version
	     Print version information and exit.

     -w, --warn
	     When verifying checksums, warn about malformed input.

     -z, --zero
	     Terminate output lines with NUL rather than with newline.

EXIT STATUS
     The  md5, sha1, sha224, sha256, sha384, and sha512 utilities exit 0 on suc-
     cess, 1 if at least one of the input files could not be read, and 2  if  at
     least one file does not have the same hash as the -c option.

     The  md5sum, sha1sum, sha224sum, sha256sum, sha384sum, and sha512sum utili-
     ties exit 0 on success and 1 if at least one of the input files  could  not
     be read or, when verifying checksums, does not have the expected checksum.

EXAMPLES
     Calculate the MD5 checksum of the string "Hello".

	   $ md5 -s Hello
	   MD5 ("Hello") = 8b1a9953c4611296a827abf8c47804d7

     Same  as  above, but note the absence of the newline character in the input
     string:

	   $ echo -n Hello | md5
	   8b1a9953c4611296a827abf8c47804d7

     Calculate the checksum of multiple files reversing the output:

	   $ md5 -r /boot/loader.conf /etc/rc.conf
	   ada5f60f23af88ff95b8091d6d67bef6 /boot/loader.conf
	   d80bf36c332dc0fdc479366ec3fa44cd /etc/rc.conf

     This is almost but not quite identical to the output from GNU mode:

	   $ md5sum /boot/loader.conf /etc/rc.conf
	   ada5f60f23af88ff95b8091d6d67bef6  /boot/loader.conf
	   d80bf36c332dc0fdc479366ec3fa44cd  /etc/rc.conf

     Note the two spaces between hash and file name.   If  binary  mode  is  re-
     quested, they are instead separated by a space and an asterisk:

	   $ md5sum -b /boot/loader.conf /etc/rc.conf
	   ada5f60f23af88ff95b8091d6d67bef6 */boot/loader.conf
	   d80bf36c332dc0fdc479366ec3fa44cd */etc/rc.conf

     Write the digest for /boot/loader.conf in a file named digest.  Then calcu-
     late  the	checksum  again  and validate it against the checksum string ex-
     tracted from the digest file:

	   $ md5 /boot/loader.conf > digest && md5 -c $(cut -f2 -d= digest) /boot/loader.conf
	   MD5 (/boot/loader.conf) = ada5f60f23af88ff95b8091d6d67bef6

     Same  as  above  but  comparing  the  digest  against  an	invalid   string
     ("randomstring"), which results in a failure.

	   $ md5 -c randomstring /boot/loader.conf
	   MD5 (/boot/loader.conf) = ada5f60f23af88ff95b8091d6d67bef6 [ Failed ]

     In GNU mode, the -c option does not compare against a hash string passed as
     parameter.   Instead,  it	expects a digest file, as created under the name
     digest for /boot/loader.conf in the example above.

	   $ md5 -c digest /boot/loader.conf
	   /boot/loader.conf: OK

     The digest file may contain any number of lines in the format generated  in
     either  BSD or GNU mode.  If a hash value does not match the file, "FAILED"
     is printed instead of "OK".

SEE ALSO
     cksum(1), md5(3), sha(3), sha256(3), sha384(3), sha512(3)

     R. Rivest, The MD5 Message-Digest Algorithm, RFC1321.

     J. Burrows, The Secure Hash Standard, FIPS PUB 180-2.

     D. Eastlake and P. Jones, US Secure Hash Algorithm 1, RFC 3174.

     Secure		    Hash		 Standard		  (SHS):
     https://www.nist.gov/publications/secure-hash-standard-shs

ACKNOWLEDGMENTS
     This  utility was originally derived from a program which was placed in the
     public domain for free general use by RSA Data Security.

     Support for SHA-1 was added by Oliver Eikemeier <eik@FreeBSD.org>.

     Support for SHA-2 was added by Colin  Percival  <cperciva@FreeBSD.org>  and
     Allan Jude <allanjude@FreeBSD.org>.

     Compatibility with GNU coreutils was added by Warner Losh <imp@FreeBSD.org>
     and much expanded by Dag-Erling Smorgrav <des@FreeBSD.org>.

macOS 26.7			February 13, 2024			  MD5(1)
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