rsa - RSA key processing tool


   openssl rsa [-inform PEM|NET|DER] [-outform PEM|NET|DER] [-in filename]
   [-passin arg] [-out filename] [-passout arg] [-sgckey] [-aes128]
   [-aes192] [-aes256] [-camellia128] [-camellia192] [-camellia256] [-des]
   [-des3] [-idea] [-text] [-noout] [-modulus] [-check] [-pubin] [-pubout]
   [-RSAPublicKey_in] [-RSAPublicKey_out] [-engine id]


   The rsa command processes RSA 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 utility.


   -inform DER|NET|PEM
       This specifies the input format. The DER option uses an ASN1 DER
       encoded form compatible with the PKCS#1 RSAPrivateKey or
       SubjectPublicKeyInfo format.  The PEM form is the default format:
       it consists of the DER format base64 encoded with additional header
       and footer lines. On input PKCS#8 format private keys are also
       accepted. The NET form is a format is described in the NOTES

   -outform DER|NET|PEM
       This specifies the output format, the options have the same meaning
       as the -inform option.

   -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.

   -passin arg
       the input file password source. For more information about the
       format of arg see the PASS PHRASE ARGUMENTS section in openssl(1).

   -out filename
       This specifies the output filename to write a key to or standard
       output if this option 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.

   -passout password
       the output file password source. For more information about the
       format of arg see the PASS PHRASE ARGUMENTS section in openssl(1).

       use the modified NET algorithm used with some versions of Microsoft
       IIS and SGC keys.

       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 using the rsa utility to read in an encrypted key with
       no encryption option can be used to remove the pass phrase from a
       key, or by setting the encryption options it can be use to add or
       change the pass phrase.  These options can only be used with PEM
       format output files.

       prints out the various public or private key components in plain
       text in addition to the encoded version.

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

       this option prints out the value of the modulus of the key.

       this option checks the consistency of an RSA private 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.

   -RSAPublicKey_in, -RSAPublicKey_out
       like -pubin and -pubout except RSAPublicKey format is used instead.

   -engine id
       specifying an engine (by its unique id string) will cause rsa to
       attempt to obtain a functional reference to the specified engine,
       thus initialising it if needed. The engine will then be set as the
       default for all available algorithms.


   The PEM private key format uses the header and footer lines:


    -----END RSA PRIVATE KEY-----
   The PEM public key format uses the header and footer lines:

    -----BEGIN PUBLIC KEY-----

    -----END PUBLIC KEY-----
   The PEM RSAPublicKey format uses the header and footer lines:

    -----BEGIN RSA PUBLIC KEY-----

    -----END RSA PUBLIC KEY-----
   The NET form is a format compatible with older Netscape servers and
   Microsoft IIS .key files, this uses unsalted RC4 for its encryption.
   It is not very secure and so should only be used when necessary.

   Some newer version of IIS have additional data in the exported .key
   files. To use these with the utility, view the file with a binary
   editor and look for the string "private-key", then trace back to the
   byte sequence 0x30, 0x82 (this is an ASN1 SEQUENCE). Copy all the data
   from this point onwards to another file and use that as the input to
   the rsa utility with the -inform NET option. If you get an error after
   entering the password try the -sgckey option.


   To remove the pass phrase on an RSA private key:

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

   To encrypt a private key using triple DES:

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

   To convert a private key from PEM to DER format:

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

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

    openssl rsa -in key.pem -text -noout

   To just output the public part of a private key:

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

   Output the public part of a private key in RSAPublicKey format:

    openssl rsa -in key.pem -RSAPublicKey_out -out pubkey.pem


   The command line password arguments don't currently work with NET

   There should be an option that automatically handles .key files,
   without having to manually edit them.


   pkcs8(1), dsa(1), genrsa(1), gendsa(1)


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