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=pod

=head1 NAME

openssl-passwd,
passwd - compute password hashes

=head1 SYNOPSIS

B<openssl passwd>
[B<-help>]
[B<-crypt>]
[B<-1>]
[B<-apr1>]
[B<-aixmd5>]
[B<-5>]
[B<-6>]
[B<-salt> I<string>]
[B<-in> I<file>]
[B<-stdin>]
[B<-noverify>]
[B<-quiet>]
[B<-table>]
[B<-rand file...>]
[B<-writerand file>]
{I<password>}

=head1 DESCRIPTION

The B<passwd> command computes the hash of a password typed at
run-time or the hash of each password in a list.  The password list is
taken from the named file for option B<-in file>, from stdin for
option B<-stdin>, or from the command line, or from the terminal otherwise.
The Unix standard algorithm B<crypt> and the MD5-based BSD password
algorithm B<1>, its Apache variant B<apr1>, and its AIX variant are available.

=head1 OPTIONS

=over 4

=item B<-help>

Print out a usage message.

=item B<-crypt>

Use the B<crypt> algorithm (default).

=item B<-1>

Use the MD5 based BSD password algorithm B<1>.

=item B<-apr1>

Use the B<apr1> algorithm (Apache variant of the BSD algorithm).

=item B<-aixmd5>

Use the B<AIX MD5> algorithm (AIX variant of the BSD algorithm).

=item B<-5>

=item B<-6>

Use the B<SHA256> / B<SHA512> based algorithms defined by Ulrich Drepper.
See L<https://www.akkadia.org/drepper/SHA-crypt.txt>.

=item B<-salt> I<string>

Use the specified salt.
When reading a password from the terminal, this implies B<-noverify>.

=item B<-in> I<file>

Read passwords from I<file>.

=item B<-stdin>

Read passwords from B<stdin>.

=item B<-noverify>

Don't verify when reading a password from the terminal.

=item B<-quiet>

Don't output warnings when passwords given at the command line are truncated.

=item B<-table>

In the output list, prepend the cleartext password and a TAB character
to each password hash.

=item B<-rand file...>

A file or files containing random data used to seed the random number
generator.
Multiple files can be specified separated by an OS-dependent character.
The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
all others.

=item [B<-writerand file>]

Writes random data to the specified I<file> upon exit.
This can be used with a subsequent B<-rand> flag.

=back

=head1 EXAMPLES

  % openssl passwd -crypt -salt xx password
  xxj31ZMTZzkVA

  % openssl passwd -1 -salt xxxxxxxx password
  $1$xxxxxxxx$UYCIxa628.9qXjpQCjM4a.

  % openssl passwd -apr1 -salt xxxxxxxx password
  $apr1$xxxxxxxx$dxHfLAsjHkDRmG83UXe8K0

  % openssl passwd -aixmd5 -salt xxxxxxxx password
  xxxxxxxx$8Oaipk/GPKhC64w/YVeFD/

=head1 COPYRIGHT

Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved.

Licensed under the OpenSSL license (the "License").  You may not use
this file except in compliance with the License.  You can obtain a copy
in the file LICENSE in the source distribution or at
L<https://www.openssl.org/source/license.html>.

=cut