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| author | Damien Miller <djm@mindrot.org> | 2013-12-07 10:41:55 +1100 |
|---|---|---|
| committer | Damien Miller <djm@mindrot.org> | 2013-12-07 10:41:55 +1100 |
| commit | bcd00abd8451f36142ae2ee10cc657202149201e (patch) | |
| tree | 946db23f1ec607d9260e46b9f6f2422e0e9c970c /PROTOCOL.key | |
| parent | f0e9060d236c0e38bec2fa1c6579fb0a2ea6458d (diff) | |
| download | openssh-git-bcd00abd8451f36142ae2ee10cc657202149201e.tar.gz | |
- markus@cvs.openbsd.org 2013/12/06 13:34:54
[authfile.c authfile.h cipher.c cipher.h key.c packet.c ssh-agent.c]
[ssh-keygen.c PROTOCOL.key] new private key format, bcrypt as KDF by
default; details in PROTOCOL.key; feedback and lots help from djm;
ok djm@
Diffstat (limited to 'PROTOCOL.key')
| -rw-r--r-- | PROTOCOL.key | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/PROTOCOL.key b/PROTOCOL.key new file mode 100644 index 00000000..959bd7ae --- /dev/null +++ b/PROTOCOL.key @@ -0,0 +1,68 @@ +This document describes the private key format for OpenSSH. + +1. Overall format + +The key consists of a header, a list of public keys, and +an encrypted list of matching private keys. + +#define AUTH_MAGIC "openssh-key-v1" + + byte[] AUTH_MAGIC + string ciphername + string kdfname + string kdfoptions + int number of keys N + string publickey1 + string publickey2 + ... + string publickeyN + string encrypted, padded list of private keys + +2. KDF options for kdfname "bcrypt" + +The options: + + string salt + uint32 rounds + +are concatenated and represented as a string. + +3. Unencrypted list of N private keys + +The list of privatekey/comment pairs is padded with the +bytes 1, 2, 3, ... until the total length is a multiple +of the cipher block size. + + uint32 checkint + uint32 checkint + string privatekey1 + string comment1 + string privatekey2 + string comment2 + ... + string privatekeyN + string commentN + char 1 + char 2 + char 3 + ... + char padlen % 255 + +Before the key is encrypted, a random integer is assigned +to both checkint fields so successful decryption can be +quickly checked by verifying that both checkint fields +hold the same value. + +4. Encryption + +The KDF is used to derive a key, IV (and other values required by +the cipher) from the passphrase. These values are then used to +encrypt the unencrypted list of private keys. + +5. No encryption + +For unencrypted keys the cipher "none" and the KDF "none" +are used with empty passphrases. The options if the KDF "none" +are the empty string. + +$OpenBSD: PROTOCOL.key,v 1.1 2013/12/06 13:34:54 markus Exp $ |