OpenPGP Message Format
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The document details the implementation of the OpenPGP message format in Java through a project called Java Privacy Guard. It covers the principles of message confidentiality, integrity, authentication, and the web of trust, while highlighting key cryptographic techniques and algorithms used in the process. The implementation, based on RFC 4880, focuses on reading, parsing, key management, and message decryption, with an outlook on future enhancements needed for full compliance.
![PGP History
Pretty Good Privacy
1991: PGP created by Phil Zimmermann
most widely used email encryption software [6]
1998: PGP 5 standardized: openPGP (RFC 4880)
2010: PGP assets sold to Symantec
for $ 300.000.000 (Enterprise Security)
Stefan More, Bakk@IAIK
6 June 13, 2014](https://image.slidesharecdn.com/2014-06-11pgp-141122113645-conversion-gate01/85/OpenPGP-Message-Format-8-320.jpg)
![De-/Encryption
Encrypt Data with Random Symmetric-Key,
encrypt Symmetric-Key with Public-Key
Multiple Receiver: Encrypt Data only once
Symmetric Cipher: AES, IDEA, 3DES, CAST5, . . .
Keysize 112 bits [7]
Public-Key Cipher: RSA, ElGamal
Keysize 2048 bits [7]
Stefan More, Bakk@IAIK
10 June 13, 2014](https://image.slidesharecdn.com/2014-06-11pgp-141122113645-conversion-gate01/85/OpenPGP-Message-Format-12-320.jpg)
![Load Decrypt PGP Message
IAIK . addAsProvider ( ) ;
PGPMessage pgpMessage = parseMessage ( i s1 ) ;
PGPPrivateKey pr ivKey = parsePr ivatekey ( i s2 ) ;
PGPCipher c ipher = new PGPCipher ( ) ;
c ipher . i n i t ( PGPCipher .DECRYPT MODE, pr i v key ) ;
byte [ ] c l e a r t e x t = c ipher . doFinal ( pgpmessage ) ;
Stefan More, Bakk@IAIK
19 June 13, 2014](https://image.slidesharecdn.com/2014-06-11pgp-141122113645-conversion-gate01/85/OpenPGP-Message-Format-24-320.jpg)
![[1] Laura Poitras
https://commons.wikimedia.org/wiki/File:Edward_Snowden-2.jpg
[2] Glenn Greenwald https://en.wikipedia.org/wiki/File:
Glenn_greenwald_portrait_transparent.png
[3] Katy Scoggin
https://commons.wikimedia.org/wiki/File:Laura_Poitras_2014.jpg
[4] Regionales RechenZentrum Erlangen
https://commons.wikimedia.org/wiki/Category:RRZE-Icon-Set
[5] The Opte Project http://www.opte.org/the-internet
[6] http://www.philzimmermann.com/EN/background/index.html
[7] Recommendation for Key Management, Special Publication 800-57 Part 1
Rev. 3, NIST, 07/2012. http://www.keylength.com/en/4/
[8] http://cirw.in/gpg-decoder
Stefan More, Bakk@IAIK
23 June 13, 2014](https://image.slidesharecdn.com/2014-06-11pgp-141122113645-conversion-gate01/85/OpenPGP-Message-Format-28-320.jpg)
OpenPGP Message Format
- 1. Java Privacy Guard An Implementation of the OpenPGP Message Format in Java Stefan More, Advisor: Dieter Bratko, Peter Lipp June 13, 2014
- 2. Overview 1. Problem Statement 2. openPGP 3. Java Privacy Guard 4. Summary & Outlook Stefan More, Bakk@IAIK 2 June 13, 2014
- 6. Problem Statement Message Confidentiality Message Integrity Sender Authentication Anonymity End to End Stefan More, Bakk@IAIK 4 June 13, 2014
- 7. openPGP Stefan More, Bakk@IAIK 5 June 13, 2014
- 8. PGP History Pretty Good Privacy 1991: PGP created by Phil Zimmermann most widely used email encryption software [6] 1998: PGP 5 standardized: openPGP (RFC 4880) 2010: PGP assets sold to Symantec for $ 300.000.000 (Enterprise Security) Stefan More, Bakk@IAIK 6 June 13, 2014
- 9. Standard: openPGP (RFC 4880 etc.) Implementations: PGP (Zimmermann, Symantec) GnuPG / GPG (GNU) APG (Android) End-to-End (Google Chrome) Bouncycastle (Java) Java Privacy Guard (IAIK-JCE) Stefan More, Bakk@IAIK 7 June 13, 2014
- 10. openPGP Combines Symmetric-Key Cryptography and Public-Key Cryptography + Hashing + Data Compression + Trust Model Stefan More, Bakk@IAIK 8 June 13, 2014
- 11. Revisiting Problem Statement Message Confidentiality: Encryption Message Integrity: Digital Signatures Sender Authentication: Web Of Trust Anonymity? Tor, I2P, . . . Stefan More, Bakk@IAIK 9 June 13, 2014
- 12. De-/Encryption Encrypt Data with Random Symmetric-Key, encrypt Symmetric-Key with Public-Key Multiple Receiver: Encrypt Data only once Symmetric Cipher: AES, IDEA, 3DES, CAST5, . . . Keysize 112 bits [7] Public-Key Cipher: RSA, ElGamal Keysize 2048 bits [7] Stefan More, Bakk@IAIK 10 June 13, 2014
- 13. Stefan More, Bakk@IAIK 11 June 13, 2014
- 14. Stefan More, Bakk@IAIK 11 June 13, 2014
- 15. Stefan More, Bakk@IAIK 11 June 13, 2014
- 16. Stefan More, Bakk@IAIK 11 June 13, 2014
- 17. Digital Signatures Hash Message Body Sign Hash with Private Key Sign Other Keys (! Trust Model) Hash Algorithms: SHA-2, SHA-1, RIPE-MD/160, MD5 Signature Algorithms: RSA, DSA Stefan More, Bakk@IAIK 12 June 13, 2014
- 18. Web Of Trust Decentralized Trust Model (Can be centralized) No Certificate Authority Transitive Trust Pathfinder: pgp.cs.uu.nl/doc/faq.html Key-Set Analysis: pgp.cs.uu.nl/plot Stefan More, Bakk@IAIK 13 June 13, 2014
- 19. Java Privacy Guard openPGP in Java using IAIK-JCE Stefan More, Bakk@IAIK 14 June 13, 2014
- 20. Java Privacy Guard Full Implementation of RFC 4880 (not yet) Compatibility to other PGP Implementations Simple API Extended API Key Management Crypto provided by JCA (default: IAIK-JCE) Stefan More, Bakk@IAIK 15 June 13, 2014
- 21. openPGP Structure Packets: Internal Structure Contain actual Data (+ Metadata) Transferable: Consists Packets Message, Keys, Signature, Keyring, . . . Stefan More, Bakk@IAIK 16 June 13, 2014
- 22. ----- BEGIN PGP MESSAGE ----- Comment : GPGTools - http :// gpgtools .org hQIOA5v3tWTQmvtJEAf / QPf5FuQMZpG + cKylmm819K2eoIv75nxTSk25tLwVkGMi IR0xOVCkTV + PNgi7aSbhNxBZ6dMJougl1cGx / XtKZ3bQ2gli5h + pxzGnRhTBzu2n BWh361unf42D9cIWV3ME + f18rZynp4EdBDk6NENdPiaV0odMdlxoDbPmrrdEzM5F ozjm6c9RJD7gDQ4KVfy13eiSX + MSgsbdMeDk0EgqwzczHl /5 ATWFMh3x + uDZ0mop 6 NXlX3rvzFoA9NkiDR0CDcYuTXspfDt6JJyDYRlgm4KEaBbP + Eh6rZK4vBIq / Bkj KK9ZwKZOtkljtMvGYWV9AD2CStOrP5lT7wFM / IAEAwf / RvAq6ixUhqjGExrcxc68 6 NB1Ka1zp4FfMYH9I3IKKQTjIVbgCqINil4hvaqUBdF7YXc / gS0skWKztqUqEKky BIW8pmKw0 + AIHuHQUtebSnd / y3LmQhlMj / WjnTEK2DeirU5e05YzKnSdZMRBDAEg GMFSs9gNgYBvrh1LQhXCdwwga05s5sOFPk4lRMAjm1eKjny74OpBv0Ze4UKWeG /4 DLhPAa5n0GZWVZ81UK5xeQEuWoH2BTtbUJ32yxFDrCFUNqRBJh67AiXQeT3gzkp7 cmjxdvSZLQd94mOChWvPAqxgG4w0SPSeJVaiDDVj0P24Lt + yHBSMOaxi3k7vWJwW moUCDAO1gB / YJnRgOQEP / iIX3 / GYPJvegETBEV8z8ug36TLlqx6VDK2B6wp7C9BB E0FfIKa6vVDmUt7FOtzHIfcu1by9U0NAt4IzIs8gO9P ++ vI72qwyjJmapkdJ6TOk w8pJn8sweV / rNT5NoYjhG10ErxtzhspQCykt8d3hx4mCoBxDYtJl6fDLceji / YJV 2 tI0 /0 I8wiKsl / EkO817 / BgjnLKQvVctqiHBlo5o4YxyxWycXVVdkctAtH4NWO0H dmr76stfCFPQTo24Fjd /1 fi8rIcHVJIv + yuEd1ZkBw / BibaCkBCseNXJUVsedEAC 0 rGcCCT56gQuGrzlmRbptvzgr2WQ + qYZJwmomZqeF4xP81A9rbWaDINr5 / slkRIZ ie9HV +6 krAaDJ9iEAJcK0yorkznFszW6 + uynljZ + sWn72Ff / UBVSktYF + J8zDISI e/6 NpeEvgL5EByrY / LEXeCzPjok3JCt7wZhqjdcrDJLveYfw2StGunxhfl33wRqx kBG0G49ba + v3fyOTSqjlA5yekZ6YkQJaQIfLCa1Guierw9oFKAENMx1xzfL4TJWW RGx54xBUmMblZPVIDgE5cWVqmaZoRH5SvlEQEi9lW8yuGVvdJfdLHdPsRSxRPwz4 fDHfpYLYM9Kj5My3inYd9NmIvWoFTFgHJuy3B3pd4pPXLxjgA + Qo3ncCneQkluDe ySG6c8b + hCyl9b4S / qBnzPumxCVZ1FUvubuAboMgGno0hd8 = =2 IUj -----END PGP MESSAGE ----- Stefan More, Bakk@IAIK 17 June 13, 2014
- 23. tag: Public-Key Encrypted Session Key Packet length: 526 version: 3 keyId: “9BF7B564D09AFB49” publicKeyAlgorithm: “Elgamal (Encrypt-Only)” encryptedSessionKey tag: Public-Key Encrypted Session Key Packet length: 524 version: 3 keyId: “B5801FD826746039” publicKeyAlgorithm: “RSA (Encrypt or Sign)” encryptedSessionKey tag: Symmetrically Encrypted Data Packet length: 33 Encrypted Data Stefan More, Bakk@IAIK 18 June 13, 2014
- 24. Load Decrypt PGP Message IAIK . addAsProvider ( ) ; PGPMessage pgpMessage = parseMessage ( i s1 ) ; PGPPrivateKey pr ivKey = parsePr ivatekey ( i s2 ) ; PGPCipher c ipher = new PGPCipher ( ) ; c ipher . i n i t ( PGPCipher .DECRYPT MODE, pr i v key ) ; byte [ ] c l e a r t e x t = c ipher . doFinal ( pgpmessage ) ; Stefan More, Bakk@IAIK 19 June 13, 2014
- 25. Summary Studied RFC 4880 IAIK-JCE Implemented: Reading ASCII-Armor (Base 64 + CRC24) Parsing PGP Message Objects (Packets) Key Management (Simple Keychain) Message Decryption (RSA ElGamal) Signature Validation (RSA DSA) Decompression Stefan More, Bakk@IAIK 20 June 13, 2014
- 26. Outlook / Future Research Message Encryption and Signature Validation Missing parts of RFC 4880 (Partial body length, . . . ) RFC 6637: ECC Keyservers? Stefan More, Bakk@IAIK 21 June 13, 2014
- 27. Thank You for Your Attention Questions? Remarks? Stefan More, Bakk@IAIK 22 June 13, 2014
- 28. [1] Laura Poitras https://commons.wikimedia.org/wiki/File:Edward_Snowden-2.jpg [2] Glenn Greenwald https://en.wikipedia.org/wiki/File: Glenn_greenwald_portrait_transparent.png [3] Katy Scoggin https://commons.wikimedia.org/wiki/File:Laura_Poitras_2014.jpg [4] Regionales RechenZentrum Erlangen https://commons.wikimedia.org/wiki/Category:RRZE-Icon-Set [5] The Opte Project http://www.opte.org/the-internet [6] http://www.philzimmermann.com/EN/background/index.html [7] Recommendation for Key Management, Special Publication 800-57 Part 1 Rev. 3, NIST, 07/2012. http://www.keylength.com/en/4/ [8] http://cirw.in/gpg-decoder Stefan More, Bakk@IAIK 23 June 13, 2014
- 29. Oracle and Java are registered trademarks of Oracle and/or its affiliates. Google and Chrome are registered trademarks of Google and/or its affiliates. Other names may be trademarks of their respective owners. Stefan More, Bakk@IAIK 24 June 13, 2014