openssl-dsa.1ossl - Man Page

DSA key processing


openssl dsa [-help] [-inform DER|PEM] [-outform DER|PEM] [-in filename] [-passin arg] [-out filename] [-passout arg] [-aes128] [-aes192] [-aes256] [-aria128] [-aria192] [-aria256] [-camellia128] [-camellia192] [-camellia256] [-des] [-des3] [-idea] [-text] [-noout] [-modulus] [-pubin] [-pubout] [-pvk-strong] [-pvk-weak] [-pvk-none] [-engine id] [-provider name] [-provider-path path] [-propquery propq]


This command processes DSA keys. They can be converted between various forms and their components printed out. Note This command uses the traditional SSLeay compatible format for private key encryption: newer applications should use the more secure PKCS#8 format using the pkcs8



Print out a usage message.

-inform DER|PEM

The key input format; unspecified by default. See openssl-format-options(1) for details.

-outform DER|PEM

The key output format; the default is PEM. See openssl-format-options(1) for details.

Private keys are a sequence of ASN.1 INTEGERS: the version (zero), p, q, g, and the public and private key components.  Public keys are a SubjectPublicKeyInfo structure with the DSA type.

The PEM format also accepts PKCS#8 data.

-in filename

This specifies the input filename to read a key from or standard input if this option is not specified. If the key is encrypted a pass phrase will be prompted for.

-out filename

This specifies the output filename to write a key to or standard output by is not specified. If any encryption options are set then a pass phrase will be prompted for. The output filename should not be the same as the input filename.

-passin arg, -passout arg

The password source for the input and output file. For more information about the format of arg see openssl-passphrase-options(1).

-aes128,  -aes192,  -aes256,  -aria128,  -aria192,  -aria256,  -camellia128,  -camellia192,  -camellia256,  -des,  -des3,  -idea

These options encrypt the private key with the specified cipher before outputting it. A pass phrase is prompted for. If none of these options is specified the key is written in plain text. This means that this command can be used to remove the pass phrase from a key by not giving any encryption option is given, or to add or change the pass phrase by setting them. These options can only be used with PEM format output files.


Prints out the public, private key components and parameters.


This option prevents output of the encoded version of the key.


This option prints out the value of the public key component of the key.


By default, a private key is read from the input file. With this option a public key is read instead.


By default, a private key is output. With this option a public key will be output instead. This option is automatically set if the input is a public key.


Enable 'Strong' PVK encoding level (default).


Enable 'Weak' PVK encoding level.


Don't enforce PVK encoding.

-engine id

See “Engine Options” in openssl(1). This option is deprecated.

-provider name
-provider-path path
-propquery propq

See “Provider Options” in openssl(1), provider(7), and property(7).

The openssl-pkey(1) command is capable of performing all the operations this command can, as well as supporting other public key types.


The documentation for the openssl-pkey(1) command contains examples equivalent to the ones listed here.

To remove the pass phrase on a DSA private key:

 openssl dsa -in key.pem -out keyout.pem

To encrypt a private key using triple DES:

 openssl dsa -in key.pem -des3 -out keyout.pem

To convert a private key from PEM to DER format:

 openssl dsa -in key.pem -outform DER -out keyout.der

To print out the components of a private key to standard output:

 openssl dsa -in key.pem -text -noout

To just output the public part of a private key:

 openssl dsa -in key.pem -pubout -out pubkey.pem

See Also

openssl(1), openssl-pkey(1), openssl-dsaparam(1), openssl-gendsa(1), openssl-rsa(1), openssl-genrsa(1)


The -engine option was deprecated in OpenSSL 3.0.

Referenced By

openssl.1ossl(1), openssl-cmds.1ossl(1), openssl-dsaparam.1ossl(1), openssl-ec.1ossl(1), openssl-gendsa.1ossl(1), openssl-pkcs8.1ossl(1), openssl-pkey.1ossl(1), openssl-pkeyparam.1ossl(1), openssl-rsa.1ossl(1).

2021-09-09 3.0.0 OpenSSL