117

In Linux I can create a SHA1 password hash using sha1pass mypassword. Is there a similar command line tool which lets me create sha512 hashes? Same question for Bcrypt and PBKDF2.

3
  • Don't you mean sha1sum?
    – user16144
    Oct 17, 2012 at 18:43
  • 1
    @Tichodroma no, there is actually a sha1pass command, part of the syslinux-common package on Debian.
    – derobert
    Oct 17, 2012 at 18:44
  • 2
    There's a sha512sum command that's part of coreutils, and similarly openssl sha512 -- but neither does the extra stuff that sha1pass does. Oct 17, 2012 at 20:37

13 Answers 13

92

On any of the Red Hat distros such as Fedora, CentOS, or RHEL the command mkpasswd doesn't include the same set of switches as the version typically included with Debian/Ubuntu.

NOTE: The command mkpasswd is actually part of the expect package, and should probably be avoided. You can find out what package it belongs to with either of these commands.

$ yum whatprovides "*/mkpasswd"
-or-
$ repoquery -q --file */mkpasswd

Example

$ repoquery -q --file */mkpasswd
expect-0:5.43.0-8.el5.x86_64
expect-0:5.43.0-8.el5.i386

Both of these methods are superior to using rpm since the packages do not have to be installed to locate */mkpasswd.

Workarounds

To work around this you can use the following Python or Perl one-liners to generate SHA-512 passwords. Take note that these are salted:

Python (>= 3.3)

$ python -c 'import crypt,getpass; print(crypt.crypt(getpass.getpass(), crypt.mksalt(crypt.METHOD_SHA512)))'

-or scripted-

$ python -c 'import crypt; print(crypt.crypt("somesecret", crypt.mksalt(crypt.METHOD_SHA512)))'

Python (2.x or 3.x)

$ python -c "import crypt, getpass, pwd; \
             print(crypt.crypt('password', '\$6\$saltsalt\$'))"

$6$saltsalt$qFmFH.bQmmtXzyBY0s9v7Oicd2z4XSIecDzlB5KiA2/jctKu9YterLp8wwnSq.qc.eoxqOmSuNp2xS0ktL3nh/

Note: $6$ designates sha512. Support for this method of specifying the algorithm is dependent on support in OS level crypt(3) library function (usually in libcrypt). It is not dependent on python version.

Perl

$ perl -e 'print crypt("password","\$6\$saltsalt\$") . "\n"'
$6$saltsalt$qFmFH.bQmmtXzyBY0s9v7Oicd2z4XSIecDzlB5KiA2/jctKu9YterLp8wwnSq.qc.eoxqOmSuNp2xS0ktL3nh/

In these examples the password is the string "password" and the salt is "saltsalt". Both examples are using $6$ which denotes that you want crypt to use SHA-512.

11
  • 3
    For the python one-liner, you can use crypt.mksalt(crypt.METHOD_SHA512) to generate the salt instead of using a fixed one.
    – Jake Cobb
    Aug 26, 2014 at 0:15
  • 2
    @JakeCobb crypt.mksalt is only available in Python 3.x Sep 24, 2014 at 7:41
  • 3
    Before typing a clear-text password at the command line make sure you have "ignorespace" set in HISTCONTROL (i.e., do this first on CentOS/RHEL: echo 'export HISTCONTROL="ignoredups:ignorespace"' > /etc/profile.d/histcontrol.sh && source /etc/profile.d/histcontrol.sh). Otherwise, it'll get saved in your ~/.bash_history.
    – Patrick
    Dec 3, 2014 at 19:38
  • 4
    the perl (and presumably the python) use the system function "crypt". So they aren't portable, they require a crypt function that understands the requested hash type. The OSX crypt doesn't - it just gives me back an old-style DES-encrypted string.
    – Dan Pritts
    Apr 13, 2016 at 21:13
  • 1
    @RiccardoMurri I have Python 2.7.5 and have access to crypt.mksalt on CentOS 7.1
    – user12345
    Jul 16, 2016 at 22:09
77

Yes, you're looking for mkpasswd, which (at least on Debian) is part of the whois package. Don't ask why...

anthony@Zia:~$ mkpasswd -m help
Available methods:
des     standard 56 bit DES-based crypt(3)
md5     MD5
sha-256 SHA-256
sha-512 SHA-512

Unfortunately, my version at least doesn't do bcrypt. If your C library does, it should (and the manpage gives a -R option to set the strength). -R also works on sha-512, but I'm not sure if its PBKDF-2 or not.

If you need to generate bcrypt passwords, you can do it fairly simply with the Crypt::Eksblowfish::Bcrypt Perl module.

22

OpenSSL has

openssl passwd -6

Help says:

$ openssl passwd --help
Usage: passwd [options]
Valid options are:
...
 -6                  SHA512-based password algorithm

For consistent output you can specify the salt:

openssl passwd -6 -salt <YOUR_SALT>

Output is something similar to:

$6$YOUR_SALT$q/oDR4twC1ik4RoxTJJtX.3MjenHVapkMaBbq2NcRHGQjqhIWRNcEVitYZhyIx98D7lF7qs0vLTq17X0nEr8I.

with: 6 between "$" indicating the algorithm ("-6" above), followed by YOUR_SALT and "$", finishing with the SHA512 sum.

1
  • (For the record, it looks like this version of openssl is not available in Debian 9)
    – Joril
    Aug 1, 2020 at 11:03
18

You can use the doveadm utility, which is included in the dovecot package.

doveadm pw -s SHA512-CRYPT

Result example:

{SHA512-CRYPT}$6$0JvQ1LLFESzA16.I$JVdKAIq0igudTq06BMqzT9rL1gRawMPwLr9U3/kBMKUqZdONfa0wubC89C35LKl3aE16CRH57BfGb4ygPLggL1

Just cut {SHA512-CRYPT} and you'll get your SHA512 hashed string.

3
  • Doesn't work for me as a regular user: doveadm(jotik): Fatal: Error reading configuration: stat(/etc/dovecot/dovecot.conf) failed: Permission denied (euid=1000(jotik) egid=100(users) missing +x perm: /etc/dovecot, we're not in group 97(dovecot), dir owned by 0:97 mode=0750)
    – jotik
    Mar 11, 2019 at 6:13
  • "Permission denied" is not related to the original question. The default dovecot setting is not to let end-user read any files in the /etc/dovecot subdirectory, particularily users (and password) file. Become root, and then you can see those files. Jan 14, 2020 at 18:02
  • 1
    The point is that doveadm cannot be run by a regular user, so this command is not a solution to the original question for someone who isn't (or cannot become) root. That someone typically isn't interested in reading any files in the /etc/dovecot directory, and shouldn't need to just in order to generate a password hash. Nov 4, 2020 at 15:31
12

Run this command:

$ /sbin/grub-crypt --sha-512

then enter the word you want hashed.

2
  • 1
    -bash: /sbin/grub-crypt: No such file or directory Nov 3, 2017 at 10:51
  • I don't believe grub is on c7 so you can use: python -c 'import crypt,getpass; print(crypt.crypt(getpass.getpass(),crypt.mksalt(crypt.METHOD_SHA512)))'
    – ucemike
    Nov 3, 2017 at 14:37
3

To expand on @slm's workarounds above, if you're worried about someone getting a hold of your bash history and seeing the plain text password, you can insert raw_input() in the python statement where the salt and password fields go so it prompts you for them. The text isn't masked while you're typing, but it won't show up in your bash history. You could also start the command with a leading space, but I always forget to do that.

python -c "import crypt, getpass, pwd; print crypt.crypt(raw_input(), '\$6\$' + raw_input() + '\$')"
1
  • 3
    You can also configure bash to not record commands prefixed with a space adding HISTCONTROL=ignorespace to your .bashrc file. When you run a command you want to exclude from your history simply type a space then the actual command.
    – theillien
    Apr 10, 2016 at 3:05
1

sha512 htpasswd

Command which asks for user and password and generates a regular htpasswd-file:

python -c 'import crypt,getpass; print(getpass.getpass("Name: ")+":"+crypt.crypt(getpass.getpass(),crypt.mksalt(crypt.METHOD_SHA512)))' >> htpasswd

Works with all python versions > 2.5.

1

I did the same thing with NodeJs before:

 echo "console.log(require('crypto').createHmac('sha512', 'nonbase64key').update('password').digest('hex'))" | node

it's equivalent in python is:

python3 -c 'import hashlib;import base64;import hmac;print(hmac.new(b"nonbase64key", "password".encode(), hashlib.sha512).hexdigest())'

And the equivalent shell command is:

echo -n "password" | openssl sha512 -hmac "nonbase64key"
1

All examples will be using SHA-512, <password> as password placeholder and <salt> as salt placeholder.

mkpasswd

Note: mkpasswd binary is installed via the package whois on Debian / Ubuntu only. On other Linux distribution such as ArchLinux, Fedora, CentOS, openSUSE, etc. mkpasswd is provided by the expect package but is an totally different utility which is available as expect_mkpasswd on Debian / Ubuntu. whois of all other Linux distro doesn't include mkpasswd but the source (C lang) can be found on the original repository https://github.com/rfc1036/whois.

# With a random password and random salt
mkpasswd -m sha-512
# With a random random salt
mkpasswd -m sha-512 '<password>'
# Choosing both password and salt
mkpasswd -m sha-512 '<password>' '<salt>'
# Read password from stdin to avoid leaking it in shell command history
mkpasswd -m sha-512 --stdin

OpenSSL

# With a random random salt
openssl passwd -6 '<password>'
# Choosing both password and salt
openssl passwd -6 --salt '<salt>' '<password>'
# Read password from stdin to avoid leaking it in shell command history
openssl passwd -6 -stdin
openssl passwd -6

Ruby

# With a random password and random salt
ruby -e 'require "securerandom"; puts SecureRandom.alphanumeric(20).crypt("$6$" + rand(36 ** 8).to_s(36))'
# With a random random salt
ruby -e 'puts "<password>".crypt("$6$" + rand(36 ** 8).to_s(36))'
# Choosing both password and salt
ruby -e 'puts "<password>".crypt("$6$<salt>")'
# Read password from stdin to avoid leaking it in shell command history
ruby -e 'require "io/console"; puts IO::console.getpass.crypt("$6$" + rand(36 ** 8).to_s(36))'

Note: for those who complains that Random#rand is a PRNG, you can use the secure SecureRandom#rand but it's not very important is rand is used only to generate the salt which is publicly available in the hash at the end.

ruby -e 'require "securerandom"; puts "<password>".crypt("$6$" + SecureRandom.rand(36 ** 8).to_s(36))'

Perl

# Choosing both password and salt
perl -le 'print crypt "<password>", "\$6\$<salt>\$"'

Python

Requires Python >= 3.3

# With a random random salt
python -c 'import crypt; print(crypt.crypt("<password>", crypt.mksalt(crypt.METHOD_SHA512)))'
# Choosing both password and salt
python -c 'import crypt; print(crypt.crypt("<password>", "$6$<salt>"))'
# Read password from stdin to avoid leaking it in shell command history
python -c 'import crypt,getpass; print(crypt.crypt(getpass.getpass(), crypt.mksalt(crypt.METHOD_SHA512)))

grub-crypt

Note: The grub package doesn't include grub-crypt in many distros.

# With a random random salt
# Read password from stdin to avoid leaking it in shell command history
grub-crypt --sha-512
0

If your using the Python (>= 2.7) method from sim's answer and want to confirm your password before it generates - because you fat finger passwords...

$ python -c 'import crypt,getpass;pw=getpass.getpass(); print(crypt.crypt(pw), crypt.mksalt(crypt.METHOD_SHA512) if (pw==getpass.getpass("Confirm: ")) else exit())'
1
  • In the Nov 29, 2017 version of this answer, it says this works for python 2.7 (or later). The crypt module of python2.7 does not have mksalt(). Also I think you want the crypt.mksalt() call as the 2nd arg to crypt.crypt() (misplaced close paren?).
    – Juan
    Mar 5, 2018 at 14:33
0

openssl version "OpenSSL 1.1.1” on Linux and openssl version "LibreSSL 2.6.5” on MacOS support md5_crypt.

Just run and enter password:

openssl passwd -crypt
Password:
Verifying - Password:
<results_into_a_md5_crypt_password>

or provide the plain text password directly to the CLI:

openssl password -crypt <plain_text_password_goes_here>
<results_into_a_md5_crypt_password>
1
  • 2
    crypt still might result in insecure classic DES implementation, taking only the first eight chars of a password. You can try that with passwd -crypt -salt oo multiple times - first using aaaaaaaa (8xa) and then using aaaaaaaaaa (10xa) - proofed when both lead to same password hash May 27, 2020 at 14:21
0

PBKDF2

I wrote a simple application in Go that allows to generate PBKDF2 hash, as OpenSSL does not provide a commandline tool for that. It supports sha1, sha256, sha512 and md5.

You can build it yourself, or download released binaries in "release" section.

https://github.com/riotkit-org/gpbkdf2

The usage is very simple:

gpbkdf2 --passphrase=my-secret-passphrase --salt=my-secret-salt --digest-algorithm=sha512 --digest-rounds=10000 --length=128
1
  • Secrets should NEVER written to a command line. Always feed them to your program via a file or an environment variable. Jun 28, 2021 at 13:57
-16

You can use sha512sum:

echo "password" | sha512sum
2
  • 32
    This answer is incorrect. The command will not generate a valid SHA-512 password hash. It will simply calculate the checksum of the string password\n (note that there is also a newline in the end). Unix password hashes are salted and include a hash version code between two "$" symbols. See the answer by @slm.
    – zorlem
    Nov 27, 2013 at 0:05
  • 1
    More specifically, the problem is that while the password is somewhat obfuscated, this method is vulnerable to a en.wikipedia.org/wiki/Rainbow_table attack. Feb 18, 2017 at 21:43

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