selective anonymity<br>
in messages encrypted to more than one key <br>
selective anonymity
in messages encrypted to more than one key
below is a message encrypted to two keys, using Disastry's 2.6.3multi6, and the fake_keyid command.
the message has the real keyid of the receiver, and the anonymous 'fake' id of the sender.
the sender can decrypt in gnupg by using the option of 'try-all-secrets'.
the message itself, and the keys are 3des, and do not require the idea algorithm to be loaded.
here is the message:
-----BEGIN PGP MESSAGE-----
Version: 2.6.3ia-multi06
comment: encrypted to real id of receiver and fake id of sender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=MkX1
-----END PGP MESSAGE-----
the fake_keyid feature in 2.6.3 multi6, requires the fake keyid string to include 16 characters for each encrypted recipient,
and they follow one another without any spaces.
in the above example, the fake_keyid for the sender and the recipient, is a string of 16 'a' characters followed by the 'real'
16 character id for the receiver's key.
here are the commands used to encrypt the above message in Disastry's pgp 2.6.3 multi6:
D:\d263m6>pgp +fake_keyid=aaaaaaaaaaaaaaaa918ab75630f42fa9 -eat d:\selat1.txt sender receiver -jd
3DES chosen for conventional encryption.
Pretty Good Privacy(tm) 2.6.3ia-multi06 - Public-key encryption for the masses
(c) 1990-96 Philip Zimmermann, Phil's Pretty Good Software. 2002-04-22
International version - for use everywhere (including USA).
Current time: 2002/10/29 16:34 GMT
PGP is now using 3DES with MD5.
Recipients' public key(s) will be used to encrypt.
Key for user ID: sender
2048-bit key, key ID 626F4B0D, created 2002/10/29
Key for user ID: receiver
2048-bit key, key ID 30F42FA9, created 2002/10/29
.
Output file 'd:\selat1.asc' already exists. Overwrite (y/N)? y
Transport armor file: d:\selat1.asc
here is the sender's key, {generated with 3des as the preferred algorithm}:
-----BEGIN PGP PRIVATE KEY BLOCK-----
Version: 2.6.3ia-multi06
Comment: passphrase: sender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=anUb
-----END PGP PRIVATE KEY BLOCK-----
-----BEGIN PGP PUBLIC KEY BLOCK-----
Version: 2.6.3ia-multi06
Comment: Acts of Kindness better the World, and protect the Soul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=rlnq
-----END PGP PUBLIC KEY BLOCK-----
and here is the receiver's key {also generated with 3des as the preferred algorithm}:
-----BEGIN PGP PRIVATE KEY BLOCK-----
Version: 2.6.3ia-multi06
Comment: passphrase: receiver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=/ni4
-----END PGP PRIVATE KEY BLOCK-----
-----BEGIN PGP PUBLIC KEY BLOCK-----
Version: 2.6.3ia-multi06
Comment: { Acts of Kindness better the World, and protect the Soul }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=TzH1
-----END PGP PUBLIC KEY BLOCK-----
hope this may be helpful in creating a selective throw-keyid switch for situations where the sender needs to remain anonymous to e-mail traffic analysis,
but allows the receiver to decrypt normally.
with Respect,
vedaal
