DOVEADM-PW(1)                                                Dovecot                                               DOVEADM-PW(1)



NAME
       doveadm-pw - Dovecot's password hash generator

SYNOPSIS
       doveadm [-Dv] pw -l
       doveadm [-Dv] pw [-p password] [-r rounds] [-s scheme] [-u user] [-V]

DESCRIPTION
       doveadm pw is used to generate password hashes for different password schemes and optionally verify the generated hash.

       All  generated password hashes have a {scheme} prefix, for example {SHA512-CRYPT.HEX}.  All passdbs have a default scheme
       for passwords stored without the {scheme} prefix.  The default scheme can be overridden by storing the password with  the
       scheme prefix.

OPTIONS
       Global doveadm(1) options:

       -D     Enables verbosity and debug messages.

       -v     Enables verbosity, including progress counter.

       Command specific options:

       -l     List all supported password schemes and exit successfully.
              There are up to three optional password schemes: BLF-CRYPT (Blowfish crypt), SHA256-CRYPT and SHA512-CRYPT.  Their
              availability depends on the system's currently used libc.

       -p password
              The plain text password for which the hash should be generated.  If no password was given doveadm(1)  will  prompt
              interactively for one.

       -r rounds
              The  password  schemes  BLF-CRYPT,  SHA256-CRYPT and SHA512-CRYPT supports a variable number of encryption rounds.
              The following table shows the minimum/maximum number of encryption rounds per scheme.   When  the  -r  option  was
              omitted the default number of encryption rounds will be applied.

               Scheme       | Minimum | Maximum   | Default
              ----------------------------------------------
               BLF-CRYPT    |       4 |        31 |       5
               SHA256-CRYPT |    1000 | 999999999 |    5000
               SHA512-CRYPT |    1000 | 999999999 |    5000

       -s scheme
              The  password scheme which should be used to generate the hashed password.  By default the CRAM-MD5 scheme will be
              used.  It is also possible to append an encoding suffix to the scheme.  Supported  encoding  suffixes  are:  .b64,
              .base64 and .hex.
              See also http://wiki2.dovecot.org/Authentication/PasswordSchemes for more details about password schemes.

       -u user
              When  the DIGEST-MD5 scheme is used, also the user name must be given, because the user name is a part of the gen-
              erated hash.  For  more  information  about  Digest-MD5  please  read  also:  http://wiki2.dovecot.org/Authentica-
              tion/Mechanisms/DigestMD5

       -V     When  this  option is given, the hashed password will be internally verified.  The result of the verification will
              be shown after the hashed password, enclosed in parenthesis.

EXAMPLE
       The first password hash is a DIGEST-MD5 hash for jane.roeATexample.com.  The second password hash is a CRAM-MD5  hash  for
       john.doeATexample.com.

       doveadm pw -s digest-md5 -u jane.roeATexample.com
       Enter new password:
       Retype new password:
       {DIGEST-MD5}9b9dcb4466233a9307bbc33708dffda0
       doveadm pw
       Enter new password:
       Retype new password:
       {CRAM-MD5}913331d8782236a8ecba7764a63aa27b26437fd40ca878d887f11d81245c2c6b

REPORTING BUGS
       Report  bugs, including doveconf -n output, to the Dovecot Mailing List <dovecotATdovecot.org>.  Information about report-
       ing bugs is available at: http://dovecot.org/bugreport.html

SEE ALSO
       doveadm(1)



Dovecot v2.0                                               2010-06-22                                              DOVEADM-PW(1)