Pretty Good Privacy (PGP)

Created
2007-07-31
Last Updated
2009-06-04

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

Registries included below

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]
16 Elgamal (Encrypt-Only) [T. Elgamal, "A Public-Key Cryptosystem and a Signature Scheme Based on Discrete 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.]
17 DSA (Digital Signature Algorithm) [Digital Signature Standard (DSS) (FIPS PUB 186-2).][FIPS 186-3 describes keys 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 unencrypted data [RFC4880]
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]
2 TripleDES (DES-EDE, [SCHNEIER] [HAC] 168 bit key derived from 192)
3 CAST5 (128 bit key, as per RFC 2144)
4 Blowfish (128 bit key, 16 rounds) [Schneier, B. "Description of a New Variable-Length Key, 64-Bit Block Cipher (Blowfish)" Fast Software Encryption, Cambridge 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 key [B. Schneier, J. Kelsey, D. Whiting, D. Wagner, C. Hall, and N. Ferguson, "The Twofish Encryption Algorithm", John Wiley & Sons, 1999.]
11 Camellia with 128 bit key [RFC5581]
12 Camellia with 192 bit key [RFC5581]
13 Camellia with 256 bit key [RFC5581]
14-99 Unassigned
100-110 Private/Experimental algorithm [RFC4880]
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]