Crypt::PK::RSA - phpMan

NAME
    Crypt::PK::RSA - Public key cryptography based on RSA

SYNOPSIS
     ### OO interface

     #Encryption: Alice
     my $pub = Crypt::PK::RSA->new('Bob_pub_rsa1.der');
     my $ct = $pub->encrypt("secret message");
     #
     #Encryption: Bob (received ciphertext $ct)
     my $priv = Crypt::PK::RSA->new('Bob_priv_rsa1.der');
     my $pt = $priv->decrypt($ct);

     #Signature: Alice
     my $priv = Crypt::PK::RSA->new('Alice_priv_rsa1.der');
     my $sig = $priv->sign_message($message);
     #
     #Signature: Bob (received $message + $sig)
     my $pub = Crypt::PK::RSA->new('Alice_pub_rsa1.der');
     $pub->verify_message($sig, $message) or die "ERROR";

     #Key generation
     my $pk = Crypt::PK::RSA->new();
     $pk->generate_key(256, 65537);
     my $private_der = $pk->export_key_der('private');
     my $public_der = $pk->export_key_der('public');
     my $private_pem = $pk->export_key_pem('private');
     my $public_pem = $pk->export_key_pem('public');

     ### Functional interface

     #Encryption: Alice
     my $ct = rsa_encrypt('Bob_pub_rsa1.der', "secret message");
     #Encryption: Bob (received ciphertext $ct)
     my $pt = rsa_decrypt('Bob_priv_rsa1.der', $ct);

     #Signature: Alice
     my $sig = rsa_sign_message('Alice_priv_rsa1.der', $message);
     #Signature: Bob (received $message + $sig)
     rsa_verify_message('Alice_pub_rsa1.der', $sig, $message) or die "ERROR";

DESCRIPTION
    The module provides a full featured RSA implementation.

METHODS
  new
      my $pk = Crypt::PK::RSA->new();
      #or
      my $pk = Crypt::PK::RSA->new($priv_or_pub_key_filename);
      #or
      my $pk = Crypt::PK::RSA->new(\$buffer_containing_priv_or_pub_key);

    Support for password protected PEM keys

      my $pk = Crypt::PK::RSA->new($priv_pem_key_filename, $password);
      #or
      my $pk = Crypt::PK::RSA->new(\$buffer_containing_priv_pem_key, $password);

  generate_key
    Uses Yarrow-based cryptographically strong random number generator
    seeded with random data taken from "/dev/random" (UNIX) or
    "CryptGenRandom" (Win32).

     $pk->generate_key($size, $e);
     # $size .. key size: 128-512 bytes (DEFAULT is 256)
     # $e ..... exponent: 3, 17, 257 or 65537 (DEFAULT is 65537)

  import_key
    Loads private or public key in DER or PEM format.

      $pk->import_key($priv_or_pub_key_filename);
      #or
      $pk->import_key(\$buffer_containing_priv_or_pub_key);

    Support for password protected PEM keys

      $pk->import_key($pem_filename, $password);
      #or
      $pk->import_key(\$buffer_containing_pem_key, $password);

    Loading private or public keys form perl hash:

     $pk->import_key($hashref);

     # the $hashref is either a key exported via key2hash
     $pk->import_key({
       e  => "10001", #public exponent
       d  => "9ED5C3D3F866E06957CA0E9478A273C39BBDA4EEAC5B...", #private exponent
       N  => "D0A5CCCAE03DF9C2F5C4C8C0CE840D62CDE279990DC6...", #modulus
       p  => "D3EF0028FFAB508E2773C659E428A80FB0E9211346B4...", #p factor of N
       q  => "FC07E46B163CAB6A83B8E467D169534B2077DCDEECAE...", #q factor of N
       qP => "88C6D406F833DF73C8B734548E0385261AD51F4187CF...", #1/q mod p CRT param
       dP => "486F142FEF0A1F53269AC43D2EE4D263E2841B60DA36...", #d mod (p - 1) CRT param
       dQ => "4597284B2968B72C4212DB7E8F24360B987B80514DA9...", #d mod (q - 1) CRT param
     });

     # or a hash with items corresponding to JWK (JSON Web Key)
     $pk->import_key({
     {
       kty => "RSA",
       n   => "0vx7agoebGcQSuuPiLJXZpt...eZu0fM4lFd2NcRwr3XPksINHaQ-G_xBniIqbw0Ls1jF44-csFCur-kEgU8awapJzKnqDKgw",
       e   => "AQAB",
       d   => "X4cTteJY_gn4FYPsXB8rdXi...FLN5EEaG6RoVH-HLKD9Mdx5ooGURknhnrRwUkC7h5fJLMWbFAKLWY2v7B6NqSzUvx0_YSf",
       p   => "83i-7IvMGXoMXCskv73TKr8...Z27zvoj6pbUQyLPBQxtPnwD20-60eTmD2ujMt5PoMrm8RmNhVWtjjMmMjOpSicFHjXOuVI",
       q   => "3dfOR9cuYq-0S-mkFLzgItg...q3hWeMuG0ouqnb3obLyuqjVZQ1dIrdgTnCdYzBcOW5r37AFXjift_NGiovonzhKpoVVS78",
       dp  => "G4sPXkc6Ya9y8oJW9_ILj4...zi_H7TkS8x5SdX3oE0oiYwxIiemTAu0UOa5pgFGyJ4c8t2VF40XRugKTP8akhFo5tA77Qe",
       dq  => "s9lAH9fggBsoFR8Oac2R_E...T2kGOhvIllTE1efA6huUvMfBcpn8lqW6vzzYY5SSF7pMd_agI3G8IbpBUb0JiraRNUfLhc",
       qi  => "GyM_p6JrXySiz1toFgKbWV...4ypu9bMWx3QJBfm0FoYzUIZEVEcOqwmRN81oDAaaBk0KWGDjJHDdDmFW3AN7I-pux_mHZG",
     });

    Supported key formats:

     # all formats can be loaded from a file
     my $pk = Crypt::PK::RSA->new($filename);

     # or from a buffer containing the key
     my $pk = Crypt::PK::RSA->new(\$buffer_with_key);

    *   RSA public keys

         -----BEGIN PUBLIC KEY-----
         MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDHlYKg9DeHB3/dY1D9WCyJTnl5
         vEzAXpUOL9tDtdPUl96brIbbdMLooO1hKjsq98kLs1q4vOn/pxvzk0BRwhiu7Vvb
         VUjAn/2HHDDL0U1utqqlMJhaffeLI3HEq5o/lSMFY7sSkZU/E4YX1yqAN0SE7xfK
         B2uzcNq60sMIfp6siQIDAQAB
         -----END PUBLIC KEY-----

    *   RSA private keys

         -----BEGIN RSA PRIVATE KEY-----
         MIICXQIBAAKBgQDHlYKg9DeHB3/dY1D9WCyJTnl5vEzAXpUOL9tDtdPUl96brIbb
         dMLooO1hKjsq98kLs1q4vOn/pxvzk0BRwhiu7VvbVUjAn/2HHDDL0U1utqqlMJha
         ffeLI3HEq5o/lSMFY7sSkZU/E4YX1yqAN0SE7xfKB2uzcNq60sMIfp6siQIDAQAB
         AoGBAI5+GgNcGQDYw9uF+t7FwxZM5sGZRJrbbEPyuvL+sDxKKW6voKCyHi4EJzaF
         9jRZMDqgVJcsmUwjPPuMGBHHJ+MI5Zb3L0jbZkyx8u+U5gf88oy9eZmfGOjmHcMB
         oCgzyoLmJETuyADg2onLanuY3jggFb3tq/jimKjO8xM2R6zhAkEA7uXWWyJI9cCN
         zrVt5R5v6oosjZ4r5VILGMqBRLrzfTvH+WDMK6Rl/2MHE+YDeLajzunaM8qY2456
         GTYEXQsIdQJBANXfMEtXocSdPtoVj3ME8Do/0r+ApgTdcDPCwXOzkmkEJW/UFMSn
         b8CYF5G6sZQN9L5z3s2nvi55PaFV8Q0LMUUCQBh9GvIQm6YFbQPpeTBpZFOIgnSp
         6BoDxPtvlryy5U7LF/6qO4OlwIbjYdBaXbS8FCKbujBg7jZjboSzEtNu1BkCQDGT
         w0Yz0jQZn3A+fzpScr2N/fSWheWqz0+wXdfMUKw3YdZCe236wlUK7KvDc1a2xX1A
         ru1NbTCoujikC3TSm2ECQQDKQshchJlZJmFv9vCFQlGCA/EX+4406xvOOiixbPYC
         pIB4Ee2cmvEdAqSaOjrvgs5zvaCCFBO0MecPStCAxUX6
         -----END RSA PRIVATE KEY-----

    *   RSA private keys in password protected PEM format

         -----BEGIN RSA PRIVATE KEY-----
         Proc-Type: 4,ENCRYPTED
         DEK-Info: DES-EDE3-CBC,4D697440FF5AEF18

         C09H49Gn99o8b8O2r4+Hqao4r3udvC+QSSfsk20sXatyuZSEmbhyqKAB+13NRj+3
         KIsRTqnL9VkeibIGgLHuekOFKAqeSVZ0PmR4bGWEFxUPAYUvg9N9pIa6hGtNZG+y
         TEpOAfFITb1pbHQhp3j8y7qmKc5kY5LrZSFE8WwA24NTG773E07wJgRxKDkXNGOl
         kki6oYArNEps0DdtHFxzgdRg0+yaotXuFJRuC5V4YzKGG/oSRcgYyXKTwCndb3xt
         aHgI2WprQAPg+qOpLABzoi7bEjCqbHWrwkvnAngylbim2Uyvw1e1xKnzlgIHU7pv
         e/J+s00pTItfqW1IpY2mh4C9nkfkfVKBKaAv7jO0s6aPySATqsdlrzv2kpF6Ub4J
         kgaZDOfZ4K3qkyAYVLWcQeDqg4glv9Ah2J05bTm4qrIMmthYnThyQlGvcjUfCMXs
         0t+mEQbsRY7xKt0o6HzzvQlJ+JsFlLORoslAubJX9iLqpEdnlrj1lD9bo6uIClZ5
         5+aoLcAyz1D4OsauuP5i8VFu+Is+QG4SN/vHVuArjkqi3VpLwSAjNDY+KWbq042l
         CqlM2mwm6FIGUZQFxiLHJD7WDmk1xmae++m+XG9CEDTfrUQ5v+l0O6BTrl80XUfU
         w3gzAWbSjz3UK0FpKeABVFPE9fjNP9fTcS6qL5YJWBPflwxCAbVgsBOW4bOMpDGK
         BJDQTeShWn4BlYCe/vgThI9ERdgZhRz4NcFeDgVA/CqQzVqptvz4PSqH46fqUN2n
         4PtJgKE5cASYUBuAjlD71FecSVVM/OTzL1uxYzXBilzvVn2vSHgo9g==
         -----END RSA PRIVATE KEY-----

    *   PKCS#8 encoded private keys

         -----BEGIN PRIVATE KEY-----
         MIICdgIBADANBgkqhkiG9w0BAQEFAASCAmAwggJcAgEAAoGBANPN17xW4EkH5PXG
         1i/i3rE1EXFcCHyxmz95VRBDs1p3MuYf9mxntbfYAmuzS3KrRWh3IyX/Eh80N/v9
         OXPlwZbVqSTX+L3pCEJtRtsWn0zmswGThjMZiwle0oWuap63L35F1QN8EDaSPSBC
         yGELNRr6rwVYq0w5b+LOcaCZ+/H1AgMBAAECgYEApfu3aGpww+rC3HUhX0+ckyTy
         cXLdV9LbxidwqRlVEb0+DyfXNucjelp2sy5EHy3na9GJovo8mmWSxhCRGKliRkQ6
         XgrEMZdCSaWI2AazuHAGlUJRFEVkvdla3AuBAn6y0YdDp/3kbg0yahmKyD8Gq74z
         nUYbDL3R5JtR2Ad/KlUCQQDvSEICTHbO/BF7hVmlKRYZSNHKEPrv8X/OlppS14Kv
         QRwc+CZ5+l6T1Y+l5cHJQUXrXZoWS1K741TXdUhjjUd7AkEA4pod804Ex8sttdWi
         pHMfeyj+IbPAk5XnBc91jT7AYIeL8ccjtfl99xhMsGFaxrh3wA/4SGEvwzWkbxcq
         H8G5TwJAKNG+0P2SVwURRm0dOdukdXPCtiHnbP9Zujhe4zr4hEUrMpXymmRntfh8
         pORpBpgoAVraams3Fe5WDttnGfSD+QJAOOC6V9HjfUrQhG3FT0XeRwm5EDiQQ/tC
         a8DxHqz7mL8tL1ju68ReC+G7jiJBqNOwqzLW/UP3uyYByiikWChGHQJAHUau7jIM
         45ErO096n94Vh95p76ANxOroWszOt39TyvJOykIfoPwFagLrBWV9Jjos2/D54KE+
         fyoy4t3yHT+/nw==
         -----END PRIVATE KEY-----

    *   PKCS#8 encrypted private keys - password protected keys (supported
        since: CryptX-0.062)

         -----BEGIN ENCRYPTED PRIVATE KEY-----
         MIICojAcBgoqhkiG9w0BDAEDMA4ECCQk+Rr1yzzcAgIIAASCAoD/mgpUFjxxM/Ty
         Yt+NeT0Fo4echgoGksqs6+rYhO16oshG664emZfkuNoFGGzJ38X6GVuqIXhlPnYQ
         biKvL37dN/KnoGytFHq9Wnk8dDwjGHPtwajhW5WuIV3NuhW/AO1PF/cRZKFjWrPt
         NWY5CrpfH6t6zojoe+5uyXpH29lQy4OqvSRdPIt/12UcB+tzV7XzSWEuXh8HAi8a
         sYUu6tuCFnq4GrD2ffM4KWFmL5GqBAwN6m0KkyrNni9XT+RaA6zEhv/lVcwg2esa
         4/EzRs0ixzzZDKaml8oCMl9RHtFAbQmdlfV7Ip4rGK9BwY6UFiDMIVru6HynOVQK
         vvZ+j//bgO+3ubrv7psX+vC9Fy/MoH2Tc7MIwDN/QVTciPZlzjWBnBNxMfeFKtEn
         d7NFiapgfLuRQIiDTMrW/clcqvO54NphxhrcgUEoxos4twKZARntqPZHtf8nEM2x
         2sEF5kI65aEF/5Yy16qvP0vZAA2B1kcIdXZ8XLZCp4c3olhkIrmgUpo1gyFXdCoC
         7dT5Cz7/YLkq5hkcFrtp4V9BZMR24fSttc4p24N5xuZ+JneGnGkLX6B+nJAtm9vw
         bZA6P+23GI0qeMzL3HJXwCOTSsWfm/H9W5+2Zmw851aAmE+pZLni/pk3e3iNSWgs
         946x/doA5O0uCFsU7oxme+WAIp2SjhxGoe808Lf1CCFMPboFi1O/E0NsX8SIEX+i
         U+UHi4kxZqVkr3Q5SB/9kiSv8K1bE787yueQOT/dsTYYaMsjAbkEZo0o/47F32T6
         A2ioXHOV/pr5zNHqE5tL+qKEcLYbAUF1O+WvmdqYz+vHQjRQBatAqTmncvLDYr/j
         1HPwZX2d
         -----END ENCRYPTED PRIVATE KEY-----

    *   RSA public key from X509 certificate

         -----BEGIN CERTIFICATE-----
         MIIC8zCCAdugAwIBAgIJAPi+LvMU3uGWMA0GCSqGSIb3DQEBCwUAMBAxDjAMBgNV
         BAMMBXBva3VzMB4XDTE3MDcxNDE0MTAyMFoXDTIwMDQwOTE0MTAyMFowEDEOMAwG
         A1UEAwwFcG9rdXMwggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIBAQDCQima
         SUIMIdz5uVevzcScbcj06xs1OLaFKUoPJ8v+xP6Ut61BQhAvc8GYuw2uRx223hZC
         r3HYLfSdWIfmOIAtlL8cPYPVoSivJtpSGE6fBG1tlBjVgXWRmJGR/oxx6Y5QDwcB
         Q4GZKga8TtHQoY5idZuatYOFZGfMIcIUC0Uoda+YSypnw7A90F/JvlpcTUh3Fnem
         VinqEA6XOegU9dCZk/29sXqauBjbdGihh8DvpklOhY16eQoiR3909AywQ0KUmI+R
         Sa9E8oIsmUDetFuXEvana+sD3y42tU+cd2nhBPRETbSXPcum0B3uF4yKgweuJy5D
         cvtVQIFVkkh4+AWNAgMBAAGjUDBOMB0GA1UdDgQWBBSS6V5PVGyN92NoB0AVLcOb
         pzR3SzAfBgNVHSMEGDAWgBSS6V5PVGyN92NoB0AVLcObpzR3SzAMBgNVHRMEBTAD
         AQH/MA0GCSqGSIb3DQEBCwUAA4IBAQBIszrBjoJ39axsS6Btbvwvo8vAmgiSWsav
         7AmjXOAwknHPaCcDmrdOys5POD0DNRwNeRsnxFiZ/UL8Vmj2JGDLgAw+/v32MwfX
         Ig7m+oIbO8KqDzlYvS5kd3suJ5C21hHy1/JUtfofZLovZH7ZRzhTAoRvCYaodW90
         2o8ZqmyCdcXPzjFmoJ2xYzs/Sf8/E1cHfb+4HjOpeRnKxDvG0gwWzcsXpUrw2pNO
         Oztj6Rd0THNrf/anIeYVtAHX4aqZA8Kbv2TyJd+9g78usFw1cn+8vfmilm6Pn0DQ
         a+I5GyGd7BJI8wYuWqIStzvrJHbQQaNrSk7hgjWYiYlcsPh6w2QP
         -----END CERTIFICATE-----

    *   SSH public RSA keys

         ssh-rsa AAAAB3NzaC1yc2EAAAADAQA...6mdYs5iJNGu/ltUdc=

    *   SSH public RSA keys (RFC-4716 format)

         ---- BEGIN SSH2 PUBLIC KEY ----
         Comment: "768-bit RSA, converted from OpenSSH"
         AAAAB3NzaC1yc2EAAAADAQABAAAAYQDYebeGQFCnlQiNRE7r9UEbjr+DQMTdw1ZHGB2w6x
         D/DzKem8761GdCpqsLrGaw2D7aSIoP1B5Sz870YoVWHn6Ao7Hvm17V3Kxfn4B01GNQTM5+
         L26mdYs5iJNGu/ltUdc=
         ---- END SSH2 PUBLIC KEY ----

    *   RSA private keys in JSON Web Key (JWK) format

        See <http://tools.ietf.org/html/draft-ietf-jose-json-web-key>

         {
           "kty":"RSA",
           "n":"0vx7agoebGcQSuuPiLJXZpt...eZu0fM4lFd2NcRwr3XPksINHaQ-G_xBniIqbw0Ls1jF44-csFCur-kEgU8awapJzKnqDKgw",
           "e":"AQAB",
           "d":"X4cTteJY_gn4FYPsXB8rdXi...FLN5EEaG6RoVH-HLKD9Mdx5ooGURknhnrRwUkC7h5fJLMWbFAKLWY2v7B6NqSzUvx0_YSf",
           "p":"83i-7IvMGXoMXCskv73TKr8...Z27zvoj6pbUQyLPBQxtPnwD20-60eTmD2ujMt5PoMrm8RmNhVWtjjMmMjOpSicFHjXOuVI",
           "q":"3dfOR9cuYq-0S-mkFLzgItg...q3hWeMuG0ouqnb3obLyuqjVZQ1dIrdgTnCdYzBcOW5r37AFXjift_NGiovonzhKpoVVS78",
           "dp":"G4sPXkc6Ya9y8oJW9_ILj4...zi_H7TkS8x5SdX3oE0oiYwxIiemTAu0UOa5pgFGyJ4c8t2VF40XRugKTP8akhFo5tA77Qe",
           "dq":"s9lAH9fggBsoFR8Oac2R_E...T2kGOhvIllTE1efA6huUvMfBcpn8lqW6vzzYY5SSF7pMd_agI3G8IbpBUb0JiraRNUfLhc",
           "qi":"GyM_p6JrXySiz1toFgKbWV...4ypu9bMWx3QJBfm0FoYzUIZEVEcOqwmRN81oDAaaBk0KWGDjJHDdDmFW3AN7I-pux_mHZG",
         }

        BEWARE: For JWK support you need to have JSON module installed.

    *   RSA public keys in JSON Web Key (JWK) format

         {
           "kty":"RSA",
           "n": "0vx7agoebGcQSuuPiLJXZp...tN9nndrQmbXEps2aiAFbWhM78LhWx4cbbfAAtVT86zwu1RK7aPFFxuhDR1L6tSoc_BJECP",
           "e":"AQAB",
         }

        BEWARE: For JWK support you need to have JSON module installed.

  export_key_der
     my $private_der = $pk->export_key_der('private');
     #or
     my $public_der = $pk->export_key_der('public');

  export_key_pem
     my $private_pem = $pk->export_key_pem('private');
     #or
     my $public_pem = $pk->export_key_pem('public');
     #or
     my $public_pem = $pk->export_key_pem('public_x509');

    With parameter 'public' uses header and footer lines:

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

    With parameter 'public_x509' uses header and footer lines:

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

    Support for password protected PEM keys

     my $private_pem = $pk->export_key_pem('private', $password);
     #or
     my $private_pem = $pk->export_key_pem('private', $password, $cipher);

     # supported ciphers: 'DES-CBC'
     #                    'DES-EDE3-CBC'
     #                    'SEED-CBC'
     #                    'CAMELLIA-128-CBC'
     #                    'CAMELLIA-192-CBC'
     #                    'CAMELLIA-256-CBC'
     #                    'AES-128-CBC'
     #                    'AES-192-CBC'
     #                    'AES-256-CBC' (DEFAULT)

  export_key_jwk
    *Since: CryptX-0.022*

    Exports public/private keys as a JSON Web Key (JWK).

     my $private_json_text = $pk->export_key_jwk('private');
     #or
     my $public_json_text = $pk->export_key_jwk('public');

    Also exports public/private keys as a perl HASH with JWK structure.

     my $jwk_hash = $pk->export_key_jwk('private', 1);
     #or
     my $jwk_hash = $pk->export_key_jwk('public', 1);

    BEWARE: For JWK support you need to have JSON module installed.

  export_key_jwk_thumbprint
    *Since: CryptX-0.031*

    Exports the key's JSON Web Key Thumbprint as a string.

    If you don't know what this is, see RFC 7638
    <https://tools.ietf.org/html/rfc7638>.

     my $thumbprint = $pk->export_key_jwk_thumbprint('SHA256');

  encrypt
     my $pk = Crypt::PK::RSA->new($pub_key_filename);
     my $ct = $pk->encrypt($message);
     #or
     my $ct = $pk->encrypt($message, $padding);
     #or
     my $ct = $pk->encrypt($message, 'oaep', $hash_name, $lparam);

     # $padding .................... 'oaep' (DEFAULT), 'v1.5' or 'none' (INSECURE)
     # $hash_name (only for oaep) .. 'SHA1' (DEFAULT), 'SHA256' or any other hash supported by Crypt::Digest
     # $lparam (only for oaep) ..... DEFAULT is empty string

  decrypt
     my $pk = Crypt::PK::RSA->new($priv_key_filename);
     my $pt = $pk->decrypt($ciphertext);
     #or
     my $pt = $pk->decrypt($ciphertext, $padding);
     #or
     my $pt = $pk->decrypt($ciphertext, 'oaep', $hash_name, $lparam);

     # $padding .................... 'oaep' (DEFAULT), 'v1.5' or 'none' (INSECURE)
     # $hash_name (only for oaep) .. 'SHA1' (DEFAULT), 'SHA256' or any other hash supported by Crypt::Digest
     # $lparam (only for oaep) ..... DEFAULT is empty string

  sign_message
     my $pk = Crypt::PK::RSA->new($priv_key_filename);
     my $signature = $priv->sign_message($message);
     #or
     my $signature = $priv->sign_message($message, $hash_name);
     #or
     my $signature = $priv->sign_message($message, $hash_name, $padding);
     #or
     my $signature = $priv->sign_message($message, $hash_name, 'pss', $saltlen);

     # $hash_name ............... 'SHA1' (DEFAULT), 'SHA256' or any other hash supported by Crypt::Digest
     # $padding ................. 'pss' (DEFAULT) or 'v1.5' or 'none' (INSECURE)
     # $saltlen (only for pss) .. DEFAULT is 12

  verify_message
     my $pk = Crypt::PK::RSA->new($pub_key_filename);
     my $valid = $pub->verify_message($signature, $message);
     #or
     my $valid = $pub->verify_message($signature, $message, $hash_name);
     #or
     my $valid = $pub->verify_message($signature, $message, $hash_name, $padding);
     #or
     my $valid = $pub->verify_message($signature, $message, $hash_name, 'pss', $saltlen);

     # $hash_name ............... 'SHA1' (DEFAULT), 'SHA256' or any other hash supported by Crypt::Digest
     # $padding ................. 'pss' (DEFAULT) or 'v1.5' or 'none' (INSECURE)
     # $saltlen (only for pss) .. DEFAULT is 12

  sign_hash
     my $pk = Crypt::PK::RSA->new($priv_key_filename);
     my $signature = $priv->sign_hash($message_hash);
     #or
     my $signature = $priv->sign_hash($message_hash, $hash_name);
     #or
     my $signature = $priv->sign_hash($message_hash, $hash_name, $padding);
     #or
     my $signature = $priv->sign_hash($message_hash, $hash_name, 'pss', $saltlen);

     # $hash_name ............... 'SHA1' (DEFAULT), 'SHA256' or any other hash supported by Crypt::Digest
     # $padding ................. 'pss' (DEFAULT) or 'v1.5' or 'none' (INSECURE)
     # $saltlen (only for pss) .. DEFAULT is 12

  verify_hash
     my $pk = Crypt::PK::RSA->new($pub_key_filename);
     my $valid = $pub->verify_hash($signature, $message_hash);
     #or
     my $valid = $pub->verify_hash($signature, $message_hash, $hash_name);
     #or
     my $valid = $pub->verify_hash($signature, $message_hash, $hash_name, $padding);
     #or
     my $valid = $pub->verify_hash($signature, $message_hash, $hash_name, 'pss', $saltlen);

     # $hash_name ............... 'SHA1' (DEFAULT), 'SHA256' or any other hash supported by Crypt::Digest
     # $padding ................. 'pss' (DEFAULT) or 'v1.5' or 'none' (INSECURE)
     # $saltlen (only for pss) .. DEFAULT is 12

  is_private
     my $rv = $pk->is_private;
     # 1 .. private key loaded
     # 0 .. public key loaded
     # undef .. no key loaded

  size
     my $size = $pk->size;
     # returns key size in bytes or undef if no key loaded

  key2hash
     my $hash = $pk->key2hash;

     # returns hash like this (or undef if no key loaded):
     {
       type => 1,   # integer: 1 .. private, 0 .. public
       size => 256, # integer: key size in bytes
       # all the rest are hex strings
       e  => "10001", #public exponent
       d  => "9ED5C3D3F866E06957CA0E9478A273C39BBDA4EEAC5B...", #private exponent
       N  => "D0A5CCCAE03DF9C2F5C4C8C0CE840D62CDE279990DC6...", #modulus
       p  => "D3EF0028FFAB508E2773C659E428A80FB0E9211346B4...", #p factor of N
       q  => "FC07E46B163CAB6A83B8E467D169534B2077DCDEECAE...", #q factor of N
       qP => "88C6D406F833DF73C8B734548E0385261AD51F4187CF...", #1/q mod p CRT param
       dP => "486F142FEF0A1F53269AC43D2EE4D263E2841B60DA36...", #d mod (p - 1) CRT param
       dQ => "4597284B2968B72C4212DB7E8F24360B987B80514DA9...", #d mod (q - 1) CRT param
     }

FUNCTIONS
  rsa_encrypt
    RSA based encryption. See method "encrypt" below.

     my $ct = rsa_encrypt($pub_key_filename, $message);
     #or
     my $ct = rsa_encrypt(\$buffer_containing_pub_key, $message);
     #or
     my $ct = rsa_encrypt($pub_key, $message, $padding);
     #or
     my $ct = rsa_encrypt($pub_key, $message, 'oaep', $hash_name, $lparam);

     # $padding .................... 'oaep' (DEFAULT), 'v1.5' or 'none' (INSECURE)
     # $hash_name (only for oaep) .. 'SHA1' (DEFAULT), 'SHA256' or any other hash supported by Crypt::Digest
     # $lparam (only for oaep) ..... DEFAULT is empty string

  rsa_decrypt
    RSA based decryption. See method "decrypt" below.

     my $pt = rsa_decrypt($priv_key_filename, $ciphertext);
     #or
     my $pt = rsa_decrypt(\$buffer_containing_priv_key, $ciphertext);
     #or
     my $pt = rsa_decrypt($priv_key, $ciphertext, $padding);
     #or
     my $pt = rsa_decrypt($priv_key, $ciphertext, 'oaep', $hash_name, $lparam);

     # $padding .................... 'oaep' (DEFAULT), 'v1.5' or 'none' (INSECURE)
     # $hash_name (only for oaep) .. 'SHA1' (DEFAULT), 'SHA256' or any other hash supported by Crypt::Digest
     # $lparam (only for oaep) ..... DEFAULT is empty string

  rsa_sign_message
    Generate RSA signature. See method "sign_message" below.

     my $sig = rsa_sign_message($priv_key_filename, $message);
     #or
     my $sig = rsa_sign_message(\$buffer_containing_priv_key, $message);
     #or
     my $sig = rsa_sign_message($priv_key, $message, $hash_name);
     #or
     my $sig = rsa_sign_message($priv_key, $message, $hash_name, $padding);
     #or
     my $sig = rsa_sign_message($priv_key, $message, $hash_name, 'pss', $saltlen);

     # $hash_name ............... 'SHA1' (DEFAULT), 'SHA256' or any other hash supported by Crypt::Digest
     # $padding ................. 'pss' (DEFAULT) or 'v1.5' or 'none' (INSECURE)
     # $saltlen (only for pss) .. DEFAULT is 12

  rsa_verify_message
    Verify RSA signature. See method "verify_message" below.

     rsa_verify_message($pub_key_filename, $signature, $message) or die "ERROR";
     #or
     rsa_verify_message(\$buffer_containing_pub_key, $signature, $message) or die "ERROR";
     #or
     rsa_verify_message($pub_key, $signature, $message, $hash_name) or die "ERROR";
     #or
     rsa_verify_message($pub_key, $signature, $message, $hash_name, $padding) or die "ERROR";
     #or
     rsa_verify_message($pub_key, $signature, $message, $hash_name, 'pss', $saltlen) or die "ERROR";

     # $hash_name ............... 'SHA1' (DEFAULT), 'SHA256' or any other hash supported by Crypt::Digest
     # $padding ................. 'pss' (DEFAULT) or 'v1.5' or 'none' (INSECURE)
     # $saltlen (only for pss) .. DEFAULT is 12

  rsa_sign_hash
    Generate RSA signature. See method "sign_hash" below.

     my $sig = rsa_sign_hash($priv_key_filename, $message_hash);
     #or
     my $sig = rsa_sign_hash(\$buffer_containing_priv_key, $message_hash);
     #or
     my $sig = rsa_sign_hash($priv_key, $message_hash, $hash_name);
     #or
     my $sig = rsa_sign_hash($priv_key, $message_hash, $hash_name, $padding);
     #or
     my $sig = rsa_sign_hash($priv_key, $message_hash, $hash_name, 'pss', $saltlen);

     # $hash_name ............... 'SHA1' (DEFAULT), 'SHA256' or any other hash supported by Crypt::Digest
     # $padding ................. 'pss' (DEFAULT) or 'v1.5' or 'none' (INSECURE)
     # $saltlen (only for pss) .. DEFAULT is 12

  rsa_verify_hash
    Verify RSA signature. See method "verify_hash" below.

     rsa_verify_hash($pub_key_filename, $signature, $message_hash) or die "ERROR";
     #or
     rsa_verify_hash(\$buffer_containing_pub_key, $signature, $message_hash) or die "ERROR";
     #or
     rsa_verify_hash($pub_key, $signature, $message_hash, $hash_name) or die "ERROR";
     #or
     rsa_verify_hash($pub_key, $signature, $message_hash, $hash_name, $padding) or die "ERROR";
     #or
     rsa_verify_hash($pub_key, $signature, $message_hash, $hash_name, 'pss', $saltlen) or die "ERROR";

     # $hash_name ............... 'SHA1' (DEFAULT), 'SHA256' or any other hash supported by Crypt::Digest
     # $padding ................. 'pss' (DEFAULT) or 'v1.5' or 'none' (INSECURE)
     # $saltlen (only for pss) .. DEFAULT is 12

OpenSSL interoperability
     ### let's have:
     # RSA private key in PEM format - rsakey.priv.pem
     # RSA public key in PEM format  - rsakey.pub.pem
     # data file to be signed or encrypted - input.data

  Encrypt by OpenSSL, decrypt by Crypt::PK::RSA
    Create encrypted file (from commandline):

     openssl rsautl -encrypt -inkey rsakey.pub.pem -pubin -out input.encrypted.rsa -in input.data

    Decrypt file (Perl code):

      use Crypt::PK::RSA;
      use Crypt::Misc 'read_rawfile';

      my $pkrsa = Crypt::PK::RSA->new("rsakey.priv.pem");
      my $encfile = read_rawfile("input.encrypted.rsa");
      my $plaintext = $pkrsa->decrypt($encfile, 'v1.5');
      print $plaintext;

  Encrypt by Crypt::PK::RSA, decrypt by OpenSSL
    Create encrypted file (Perl code):

      use Crypt::PK::RSA;
      use Crypt::Misc 'write_rawfile';

      my $plaintext = 'secret message';
      my $pkrsa = Crypt::PK::RSA->new("rsakey.pub.pem");
      my $encrypted = $pkrsa->encrypt($plaintext, 'v1.5');
      write_rawfile("input.encrypted.rsa", $encrypted);

    Decrypt file (from commandline):

     openssl rsautl -decrypt -inkey rsakey.priv.pem -in input.encrypted.rsa

  Sign by OpenSSL, verify by Crypt::PK::RSA
    Create signature (from commandline):

     openssl dgst -sha1 -sign rsakey.priv.pem -out input.sha1-rsa.sig input.data

    Verify signature (Perl code):

     use Crypt::PK::RSA;
     use Crypt::Digest 'digest_file';
     use Crypt::Misc 'read_rawfile';

     my $pkrsa = Crypt::PK::RSA->new("rsakey.pub.pem");
     my $signature = read_rawfile("input.sha1-rsa.sig");
     my $valid = $pkrsa->verify_hash($signature, digest_file("SHA1", "input.data"), "SHA1", "v1.5");
     print $valid ? "SUCCESS" : "FAILURE";

  Sign by Crypt::PK::RSA, verify by OpenSSL
    Create signature (Perl code):

     use Crypt::PK::RSA;
     use Crypt::Digest 'digest_file';
     use Crypt::Misc 'write_rawfile';

     my $pkrsa = Crypt::PK::RSA->new("rsakey.priv.pem");
     my $signature = $pkrsa->sign_hash(digest_file("SHA1", "input.data"), "SHA1", "v1.5");
     write_rawfile("input.sha1-rsa.sig", $signature);

    Verify signature (from commandline):

     openssl dgst -sha1 -verify rsakey.pub.pem -signature input.sha1-rsa.sig input.data

  Keys generated by Crypt::PK::RSA
    Generate keys (Perl code):

     use Crypt::PK::RSA;
     use Crypt::Misc 'write_rawfile';

     my $pkrsa = Crypt::PK::RSA->new;
     $pkrsa->generate_key(256, 65537);
     write_rawfile("rsakey.pub.der",  $pkrsa->export_key_der('public'));
     write_rawfile("rsakey.priv.der", $pkrsa->export_key_der('private'));
     write_rawfile("rsakey.pub.pem",  $pkrsa->export_key_pem('public_x509'));
     write_rawfile("rsakey.priv.pem", $pkrsa->export_key_pem('private'));
     write_rawfile("rsakey-passwd.priv.pem", $pkrsa->export_key_pem('private', 'secret'));

    Use keys by OpenSSL:

     openssl rsa -in rsakey.priv.der -text -inform der
     openssl rsa -in rsakey.priv.pem -text
     openssl rsa -in rsakey-passwd.priv.pem -text -inform pem -passin pass:secret
     openssl rsa -in rsakey.pub.der -pubin -text -inform der
     openssl rsa -in rsakey.pub.pem -pubin -text

  Keys generated by OpenSSL
    Generate keys:

     openssl genrsa -out rsakey.priv.pem 1024
     openssl rsa -in rsakey.priv.pem -out rsakey.priv.der -outform der
     openssl rsa -in rsakey.priv.pem -out rsakey.pub.pem -pubout
     openssl rsa -in rsakey.priv.pem -out rsakey.pub.der -outform der -pubout
     openssl rsa -in rsakey.priv.pem -passout pass:secret -des3 -out rsakey-passwd.priv.pem

    Load keys (Perl code):

     use Crypt::PK::RSA;

     my $pkrsa = Crypt::PK::RSA->new;
     $pkrsa->import_key("rsakey.pub.der");
     $pkrsa->import_key("rsakey.priv.der");
     $pkrsa->import_key("rsakey.pub.pem");
     $pkrsa->import_key("rsakey.priv.pem");
     $pkrsa->import_key("rsakey-passwd.priv.pem", "secret");

SEE ALSO
    *   <https://en.wikipedia.org/wiki/RSA_%28algorithm%29>