doveadm-pw (1)
Leading comments
Copyright (c) 2010-2016 Dovecot authors, see the included COPYING file
NAME
doveadm-pw - Dovecotaqs password hash generatorSYNOPSIS
doveadm [-Dv] pw -ldoveadm [-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 systemaqs 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 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: 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 jane.roe@example.com. The second password hash is a CRAM-MD5 hash for john.doe@example.com.
doveadm pw -s digest-md5 -u jane.roe@example.com
Enter new password:
Retype new password:
{DIGEST-MD5}9b9dcb4466233a9307bbc33708dffda0
doveadm pw
Enter new password:
Retype new password:
{CRAM-MD5}913331d8782236a8ecba7764a63aa27b26437fd40ca878d887f11d81245c2c6b