doveadm-pw - Dovecot's password hash generator
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]
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.
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.
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
Report bugs, including doveconf -n output, to the Dovecot
Mailing List <dovecot@dovecot.org>. Information about reporting bugs
is available at: http://dovecot.org/bugreport.html