huschi.net

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]
       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 overrid-
       den 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/dove-
              cot.conf and from the userdb with the given value.  In order  to
              override  multiple settings, the -o option may be specified mul-
              tiple 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 avail-
              ability 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 CRYPT scheme will be used (with the
              $2y$ bcrypt format).  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 pass-
              word.  You should enclose the password hash in single quotes, if
              it  contains one or more dollar signs ($).  The plain text pass-
              word 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  inter-
              nally  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.roe AT example.com.
       The second password hash is a CRAM-MD5 hash for john.doe AT example.com.
       doveadm pw -s digest-md5 -u jane.roe AT example.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
       <dovecot AT dovecot.org>.  Information about reporting bugs  is  available
       at: http://dovecot.org/bugreport.html
SEE ALSO
       doveadm(1)

Dovecot v2.3                      2015-06-05                     DOVEADM-PW(1)