Updated: 2021/Apr/14

PWHASH(1)                   General Commands Manual                  PWHASH(1)

     pwhash - hashes passwords from the command line or standard input

     pwhash [-km] [-A variant[,params]] [-b rounds] [-S rounds] [-s salt]
            [-p | string]

     pwhash prints the encrypted form of string to the standard output.  This
     is mostly useful for encrypting passwords from within scripts.

     The options are as follows:

     -b rounds
             Encrypt the string using Blowfish hashing with the specified

     -k      Run in makekey(8) compatible mode.  A single combined key (eight
             chars) and salt (two chars) with no intermediate space are read
             from standard input and the DES encrypted result is written to
             standard output without a terminating newline.

     -m      Hash the string using MD5.

     -p      Prompt for a single string with echo turned off.

     -S rounds
             Encrypt the salt with HMAC-SHA1 using the password as key and the
             specified rounds as a hint for the number of iterations.

     -A variant[,params]
             Encrypt the specified string using Argon2 hashing parameterized
             using variant variant, where variant is one of the following:
             argon2id, argon2i, argon2d.  Variant argon2id is recommended.

             Following the required variant name, three optional comma-
             delimited parameters may be provided,

             t=n Specify the number of iterations to n.  The default is 3.

             m=n Specify the memory usage in KB  to n. The default is 4096.

             p=n Specify the number of threads to n. The default is 1.

     -s salt
             Encrypt the string using DES, with the specified salt.

     If no string is specified, pwhash reads one string per line from standard
     input, encrypting each one with the chosen algorithm from above.  In the
     event that no specific algorithm is given as a command line option, the
     algorithm specified in the default class in /etc/passwd.conf will be

     For MD5,  Blowfish, and Argon2 a new random salt is automatically
     generated for each password.

     Specifying the string on the command line should be discouraged; using
     the standard input is more secure.

     The following specifies the argon2id variant, using 1 thread and 4096KB
     of memory

     pwhash -A argon2id,p=1,m=4096 -p


     crypt(3), passwd.conf(5)

NetBSD 9.99                      May 24, 2016                      NetBSD 9.99