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]
   doveadm [-Dv] pw -t hash [-p password] [-u user]

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.

   -o setting=value
          Overrides       the       configuration       setting       from
          /etc/dovecot/dovecot.conf and from the  userdb  with  the  given
          value.   In  order  to override multiple settings, the -o option
          may be specified multiple times.

   -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.

   -t hash
          Test if the given password  hash  matches  a  given  plain  text
          password.   You  should  enclose  the  password  hash  in single
          quotes, if it contains one or more dollar signs ($).  The  plain
          text  password  may  be  passed  using  the  -p option.  When no
          password was specified, doveadm(1) will prompt interactively for
          one.

   -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  generated  hash.
          For   more   information  about  Digest-MD5  please  read  also:
          http://wiki2.dovecot.org/Authentication/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  [email protected].
   The second password hash is a CRAM-MD5 hash for [email protected].

   doveadm pw -s digest-md5 -u [email protected]
   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
   <[email protected]>.  Information about reporting bugs  is  available
   at: http://dovecot.org/bugreport.html

SEE ALSO

   doveadm(1)



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