                                                              Pretty Good Privacy (PGP)

   Created
           2007-07-31

   Last Updated
           2009-05-13

   This registry is also available in XML and plain text formats.

   Registries included below

     * PGP String-to-Key (S2K)
     * PGP Packet Types/Tags
     * PGP User Attribute Types
     * Image Format Subpacket Types
     * Signature Subpacket Types
     * Signature Notation Data Subpacket Types
     * Key Server Preference Extensions
     * Reason for Revocation Extensions
     * Implementation Features
     * New Packet Versions
     * Key Flags Extensions
     * Public Key Algorithms
     * Symmetric Key Algorithms
     * Hash Algorithms
     * Compression Algorithms

PGP String-to-Key (S2K)

   Reference
           [RFC4880]

   Registration Procedures
           IETF consensus

     ID            S2K Type         Reference
      0    Simple S2K               [RFC4880]
      1    Salted S2K               [RFC4880]
      2    Reserved value           [RFC4880]
      3    Iterated and Salted S2K  [RFC4880]
    4-99   Unassigned               [RFC4880]
   100-110 Private/Experimental S2K [RFC4880]
   111-255 Unassigned               [RFC4880]

PGP Packet Types/Tags

   Reference
           [RFC4880]

   Registration Procedures
           IETF consensus

   Value                     Attribute                      Reference
     0   Reserved - a packet tag MUST NOT have this value   [RFC4880]
     1   Public-Key Encrypted Session Key Packet            [RFC4880]
     2   Signature Packet                                   [RFC4880]
     3   Symmetric-Key Encrypted Session Key Packet         [RFC4880]
     4   One-Pass Signature Packet                          [RFC4880]
     5   Secret Key Packet                                  [RFC4880]
     6   Public Key Packet                                  [RFC4880]
     7   Secret Subkey Packet                               [RFC4880]
     8   Compressed Data Packet                             [RFC4880]
     9   Symmetrically Encrypted Data Packet                [RFC4880]
    10   Marker Packet                                      [RFC4880]
    11   Literal Data Packet                                [RFC4880]
    12   Trust Packet                                       [RFC4880]
    13   User ID Packet                                     [RFC4880]
    14   Public Subkey Packet                               [RFC4880]
   15-16 Unknown
    17   User Attribute Packet                              [RFC4880]
    18   Sym. Encrypted and Integrity Protected Data Packet [RFC4880]
    19   Modification Detection Code Packet                 [RFC4880]
   20-59 Unassigned                                         [RFC4880]
   60-63 Private or Experimental Values                     [RFC4880]

PGP User Attribute Types

   Reference
           [RFC4880]

   Registration Procedures
           IETF consensus

    Value           Attribute          Reference
      0    Reserved                    [RFC4880]
      1    image                       [RFC4880]
    2-99   Unassigned                  [RFC4880]
   100-110 Experimental or private use [RFC4880]
   111-255 Unassigned                  [RFC4880]

Image Format Subpacket Types

   Reference
           [RFC4880]

   Registration Procedures
           IETF consensus

    Value           Attribute          Reference
      0    Reserved                    [RFC4880]
      1    JPEG                        [RFC4880]
    2-99   Unassigned                  [RFC4880]
   100-110 Experimental or private use [RFC4880]
   111-255 Unassigned                  [RFC4880]

Signature Subpacket Types

   Reference
           [RFC4880]

   Registration Procedures
           IETF consensus

    Value                Attribute                Reference
      0    Reserved
      1    Reserved
      2    signature creation time                [RFC4880]
      3    signature expiration time              [RFC4880]
      4    exportable certification               [RFC4880]
      5    trust signature                        [RFC4880]
      6    regular expression                     [RFC4880]
      7    revocable                              [RFC4880]
      8    Reserved
      9    key expiration time                    [RFC4880]
     10    placeholder for backward compatibility [RFC4880]
     11    preferred symmetric algorithms         [RFC4880]
     12    revocation key                         [RFC4880]
    13-15  Reserved
     16    issuer key ID                          [RFC4880]
    17-19  Reserved
     20    notation data                          [RFC4880]
     21    preferred hash algorithms              [RFC4880]
     22    preferred compression algorithms       [RFC4880]
     23    key server preferences                 [RFC4880]
     24    preferred key server                   [RFC4880]
     25    primary User ID                        [RFC4880]
     26    policy URI                             [RFC4880]
     27    key flags                              [RFC4880]
     28    signer's User ID                       [RFC4880]
     29    reason for revocation                  [RFC4880]
     30    features                               [RFC4880]
     31    signature target                       [RFC4880]
     32    embedded signature                     [RFC4880]
    33-99  Unassigned
   100-110 Private or experimental                [RFC4880]
   111-127 Unassigned                             [RFC4880]

Signature Notation Data Subpacket Types

   Reference
           [RFC4880]

   Note

 Notation names are arbitrary strings encoded in
 UTF-8. They reside two name spaces: The IETF name
 space and the user name space.

 The IETF name space is registered with IANA. These
 names MUST NOT contain the "@" character (0x40).
 This is a tag for the user name space.

   Registration Procedures
           Expert Review

   Registry is empty.

Key Server Preference Extensions

   Reference
           [RFC4880]

   Note

 This is a variable length bit field.

   Registration Procedures
           IETF Consensus

   First octet Extension  Reference
    0x00-0x07  Unassigned [RFC4880]
      0x80     No-modify  [RFC4880]

Reason for Revocation Extensions

   Reference
           [RFC4880]

   Registration Procedures
           IETF Consensus

    Value                            Flag                            Reference
      0    No reason specified (key revocations or cert revocations) [RFC4880]
      1    Key is superseded (key revocations)                       [RFC4880]
      2    Key material has been compromised (key revocations)       [RFC4880]
      3    Key is retired and no longer used (key revocations)       [RFC4880]
    4-31   Unassigned
     32    User ID information is no longer valid (cert revocations) [RFC4880]
    33-99  Unassigned
   100-110 Private Use
   111-255 Unassigned

Implementation Features

   Reference
           [RFC4880]

   Registration Procedures
           IETF Consensus

   First octet                  Feature                   Reference
      0x01     Modification Detection (packets 18 and 19) [RFC4880]
    0x02-0x80  Unassigned                                 [RFC4880]

New Packet Versions

   Reference
           [RFC4880]

   Registration Procedures
           IETF Consensus

   Registry is empty.

Key Flags Extensions

   Reference
           [RFC4880]

   Note

 The flags in this packet may appear in self-signatures or in
 certification signatures. They mean different things depending on
 who is making the statement -- for example, a certification
 signature that has the "sign data" flag is stating that the
 certification is for that use. On the other hand, the
 "communications encryption" flag in a self-signature is stating a
 preference that a given key be used for communications. Note
 however, that it is a thorny issue to determine what is
 "communications" and what is "storage." This decision is left wholly
 up to the implementation; the authors of this document do not claim
 any special wisdom on the issue, and realize that accepted opinion
 may change.

 The "split key" (0x10) and "group key" (0x80) flags are placed on a
 self-signature only; they are meaningless on a certification
 signature. They SHOULD be placed only on a direct-key signature
 (type 0x1f) or a subkey signature (type 0x18), one that refers to
 the key the flag applies to.

   Registration Procedures
           IETF Consensus

   First octet                                      Extension                                       Reference
      0x01     This key may be used to certify other keys.                                          [RFC4880]
      0x02     This key may be used to sign data.                                                   [RFC4880]
      0x04     This key may be used to encrypt communications.                                      [RFC4880]
      0x08     This key may be used to encrypt storage.                                             [RFC4880]
      0x10     The private component of this key may have been split by a secret-sharing mechanism. [RFC4880]
      0x20     This key may be used for authentication.                                             [RFC4880]
      0x80     The private component of this key may be in the possession of more than one person.  [RFC4880]

Public Key Algorithms

   Reference
           [RFC4880]

   Registration Procedures
           IETF Consensus

     ID                        Algorithm                                                            Reference
      0    Reserved
      1    RSA (Encrypt or Sign)                              [Alfred Menezes, Paul van Oorschot, and Scott Vanstone, "Handbook of Applied
                                                              Cryptography," CRC Press, 1996.]
      2    RSA Encrypt-Only
      3    RSA Sign-Only
    4-15   Unassigned                                         [RFC4880]
                                                              [T. Elgamal, "A Public-Key Cryptosystem and a Signature Scheme Based on Discrete
     16    Elgamal (Encrypt-Only)                             Logarithms," IEEE Transactions on Information Theory, v. IT-31, n. 4, 1985, pp.
                                                              469-472.][Alfred Menezes, Paul van Oorschot, and Scott Vanstone, "Handbook of Applied
                                                              Cryptography," CRC Press, 1996.]
                                                              [Digital Signature Standard (DSS) (FIPS PUB 186-2).][FIPS 186-3 describes keys
     17    DSA (Digital Signature Algorithm)                  greater than 1024 bits.][Alfred Menezes, Paul van Oorschot, and Scott Vanstone,
                                                              "Handbook of Applied Cryptography," CRC Press, 1996.]
     18    Reserved for Elliptic Curve
     19    Reserved for ECDSA
     20    Reserved (formerly Elgamal Encrypt or Sign)
     21    Reserved for Diffie-Hellman (X9.42, as defined for
           IETF-S/MIME)
    22-99  Unassigned
   100-110 Private/Experimental algorithm
   111-255 Unassigned

Symmetric Key Algorithms

   Reference
           [RFC4880]

   Registration Procedures
           IETF Consensus

  ID         Algorithm                                                                    Reference
   0    Plaintext or         [RFC4880]
        unencrypted data
   1    IDEA                 [Lai, X., "On the design and security of block ciphers", ETH Series in Information Processing, J.L. Massey (editor), Vol. 1,
                             Hartung-Gorre Verlag Knostanz, Technische Hochschule (Zurich), 1992]
        TripleDES (DES-EDE,
   2    [SCHNEIER] [HAC] 168
        bit key derived from
        192)
   3    CAST5 (128 bit key,
        as per RFC 2144)
   4    Blowfish (128 bit    [Schneier, B. "Description of a New Variable-Length Key, 64-Bit Block Cipher (Blowfish)" Fast Software Encryption, Cambridge
        key, 16 rounds)      Security Workshop Proceedings (December 1993), Springer-Verlag, 1994, pp191-204]
   5    Reserved
   6    Reserved
   7    AES with 128-bit key [http://csrc.nist.gov/encryption/aes/round2/aesfact.html][http://csrc.nist.gov/encryption/aes/round2/r2algs.html#Rijndael][Advanced
                             Encryption Standards Questions and Answers]
   8    AES with 192-bit key [http://csrc.nist.gov/encryption/aes/round2/aesfact.html][http://csrc.nist.gov/encryption/aes/round2/r2algs.html#Rijndael][Advanced
                             Encryption Standards Questions and Answers]
   9    AES with 256-bit key [http://csrc.nist.gov/encryption/aes/round2/aesfact.html][http://csrc.nist.gov/encryption/aes/round2/r2algs.html#Rijndael][Advanced
                             Encryption Standards Questions and Answers]
  10    Twofish with 256-bit [B. Schneier, J. Kelsey, D. Whiting, D. Wagner, C. Hall, and N. Ferguson, "The Twofish Encryption Algorithm", John Wiley & Sons,
        key                  1999.]
  11    Camellia with 128    [RFC-ietf-openpgp-camellia-04]
        bit key
  12    Camellia with 192    [RFC-ietf-openpgp-camellia-04]
        bit key
  13    Camellia with 256    [RFC-ietf-openpgp-camellia-04]
        bit key
 14-99  Unassigned
100-110 Private/Experimental [RFC4880]
        algorithm
111-255 Unassigned

Hash Algorithms

   Reference
           [RFC4880]

   Registration Procedures
           IETF Consensus

     ID              Algorithm             Text Name                                            Reference
      1    MD5 (deprecated)               "MD5"       [Alfred Menezes, Paul van Oorschot, and Scott Vanstone, "Handbook of Applied Cryptography,"
                                                      CRC Press, 1996.][RFC1321]
      2    SHA-1                          "SHA1"      [[FIPS180]]
      3    RIPE-MD/160                    "RIPEMD160" [Alfred Menezes, Paul van Oorschot, and Scott Vanstone, "Handbook of Applied Cryptography,"
                                                      CRC Press, 1996.]
     4-7   Reserved                                   [RFC4880]
      8    SHA256                         "SHA256"    [[FIPS180]]
      9    SHA384                         "SHA384"    [[FIPS180]]
     10    SHA512                         "SHA512"    [[FIPS180]]
     11    SHA224                         "SHA224"    [[FIPS180]]
    12-99  Unassigned                                 [RFC4880]
   100-110 Private/Experimental algorithm
   111-255 Unassigned                                 [RFC4880]

Compression Algorithms

   Reference
           [RFC4880]

   Registration Procedures
           IETF Consensus

     ID              Algorithm                                       Reference
      0    Uncompressed                   [RFC4880]
      1    ZIP                            [RFC1951]
      2    ZLIB                           [RFC1950]
      3    BZip2                          [J. Seward, jseward&acm.org, "The Bzip2 and libbzip2 home page"]
    4-99   Unassigned                     [RFC4880]
   100-110 Private/Experimental algorithm [RFC4880]
   111-255 Unassigned                     [RFC4880]
