1DOVEADM-PW(1) Dovecot DOVEADM-PW(1)
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6 doveadm-pw - Dovecot's password hash generator
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9 doveadm [-Dv] pw -l
10 doveadm [-Dv] pw [-p password] [-r rounds] [-s scheme] [-u user] [-V]
11 doveadm [-Dv] pw -t hash [-p password] [-u user]
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14 doveadm pw is used to generate password hashes for different password
15 schemes and optionally verify the generated hash.
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17 All generated password hashes have a {scheme} prefix, for example
18 {SHA512-CRYPT.HEX}. All passdbs have a default scheme for passwords
19 stored without the {scheme} prefix. The default scheme can be overrid‐
20 den by storing the password with the scheme prefix.
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23 Global doveadm(1) options:
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25 -D Enables verbosity and debug messages.
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27 -o setting=value
28 Overrides the configuration setting from /etc/dovecot/dove‐
29 cot.conf and from the userdb with the given value. In order to
30 override multiple settings, the -o option may be specified mul‐
31 tiple times.
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33 -v Enables verbosity, including progress counter.
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35 Command specific options:
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37 -l List all supported password schemes and exit successfully.
38 There are up to three optional password schemes: BLF-CRYPT
39 (Blowfish crypt), SHA256-CRYPT and SHA512-CRYPT. Their avail‐
40 ability depends on the system's currently used libc.
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42 -p password
43 The plain text password for which the hash should be generated.
44 If no password was given doveadm(1) will prompt interactively
45 for one.
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47 -r rounds
48 The password schemes BLF-CRYPT, SHA256-CRYPT and SHA512-CRYPT
49 supports a variable number of encryption rounds. The following
50 table shows the minimum/maximum number of encryption rounds per
51 scheme. When the -r option was omitted the default number of
52 encryption rounds will be applied.
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54 Scheme | Minimum | Maximum | Default
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56 BLF-CRYPT | 4 | 31 | 5
57 SHA256-CRYPT | 1000 | 999999999 | 5000
58 SHA512-CRYPT | 1000 | 999999999 | 5000
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60 -s scheme
61 The password scheme which should be used to generate the hashed
62 password. By default the CRAM-MD5 scheme will be used. It is
63 also possible to append an encoding suffix to the scheme. Sup‐
64 ported encoding suffixes are: .b64, .base64 and .hex.
65 See also http://wiki2.dovecot.org/Authentication/PasswordSchemes
66 for more details about password schemes.
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68 -t hash
69 Test if the given password hash matches a given plain text pass‐
70 word. You should enclose the password hash in single quotes, if
71 it contains one or more dollar signs ($). The plain text pass‐
72 word may be passed using the -p option. When no password was
73 specified, doveadm(1) will prompt interactively for one.
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75 -u user
76 When the DIGEST-MD5 scheme is used, also the user name must be
77 given, because the user name is a part of the generated hash.
78 For more information about Digest-MD5 please read also:
79 http://wiki2.dovecot.org/Authentication/Mechanisms/DigestMD5
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81 -V When this option is given, the hashed password will be inter‐
82 nally verified. The result of the verification will be shown
83 after the hashed password, enclosed in parenthesis.
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86 The first password hash is a DIGEST-MD5 hash for jane.roe@example.com.
87 The second password hash is a CRAM-MD5 hash for john.doe@example.com.
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89 doveadm pw -s digest-md5 -u jane.roe@example.com
90 Enter new password:
91 Retype new password:
92 {DIGEST-MD5}9b9dcb4466233a9307bbc33708dffda0
93 doveadm pw
94 Enter new password:
95 Retype new password:
96 {CRAM-MD5}913331d8782236a8ecba7764a63aa27b26437fd40ca878d887f11d81245c2c6b
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99 Report bugs, including doveconf -n output, to the Dovecot Mailing List
100 <dovecot@dovecot.org>. Information about reporting bugs is available
101 at: http://dovecot.org/bugreport.html
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104 doveadm(1)
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108Dovecot v2.3 2015-06-05 DOVEADM-PW(1)