4 Possible SILC protocol and specification document changes. All of these
5 are tentative and doesn't mean that any of them would be done at any
8 o Full rework of the documents as requested by RFC Editor. The plan
9 is to create only two documents:
11 silc-architecture-xx.txt
12 silc-specification-xx.txt
14 o Make @ reserved character in channel names. Accept channel@server
15 names in all commands and notify types.
17 o Add acknowlegments section to specification documents.
19 o Group Diffie-Hellman protocol for establishig key with two or more
22 o Change CTR mode description:
24 Truncated HASH from SKE (4 bytes) - This value is the first 4
25 bytes from the HASH value that was computed as a result of SKE
26 protocol. This acts as session identifier and each rekey MUST
27 produce a new HASH value.
31 Truncated HASH from SKE (4 bytes) - This value is the first 4
32 bytes from the HASH value that was computed in SKE. In each rekey
33 the value MUST be recomputed as follows:
35 HASH = hash(new Sending/Receiving IV from SKE)
37 The hash function is the one used in SKE. The 'new Sending/Receiving
38 IV from SKE' is the first 8 bytes of the new value computed during
39 rekey. The first 4 bytes are used from the recomputed HASH.
41 o Extend the Channel ID port to be actually a counter, allowing the
42 2^32 channels per cell, instead of 2^16 like now. The port with
43 compliant implementation would always be 706, and it could be used
44 as a counter, starting from 706... For interop, with old code.
46 o In SKE with UDP/IP responder doesn't have to do retransmissions.
47 Initiator will retransmit its packet. Initiator can be considered
48 the one that actually WANTs to establish the keys. So no need for
49 responder to retransmit. Define this clearly in the specs.
51 o Define clearly that the DSS signature format is the the Dss-Sig-Value
52 ASN.1 encoding defined for PKIX.
54 o Define clearly the SSH2 signature format is the one specified for SSH2
57 o Dynamic server and router connections, ala Jabber. SILC has allowed
58 this from the beginning. It should be written out clearly in the
59 specs. Connection would be created with nick strings (which are of
62 o NAT detection protocool during SKE so that party behind NAT can
63 detect if it is behind NAT and receive the public IP address and port
64 that it may need (servers need it to create valid Server ID). (***DONE)
66 o Counter block send/receive IV 64 bits instead of 32 bits, and the
67 value itself is used as 64-bit MSB ordered counter, which must
68 be reset before the packet sequence counter wraps. It's basically
69 a counter which is initially set to a random value. (***DONE)
71 o Nickname to NEW_CLIENT packet. (***DONE)
73 o Add Source and Destination ID in message MAC computation to fully
74 associate the Message Payload with the true sender and the true
75 recipient of the message. This will fix some security issues that
76 currently exists. It is currently possible in some specific set of
77 conditions to mount a replay attack using Message Payload. This change
78 will remove the possibility of these attacks.
80 After including Source and Destination ID in message MAC, ONLY replay
81 attack possible is the following and with ONLY following conditions:
83 1. the attacker is able to record encrypted Message Payloads and has
84 the ability to replay them.
85 2. the message payload is encrypted with static private message key
86 3. the original sender of the message is not anymore in the network,
87 has changed nickname, has detached and resumed, or has reconnected
89 4. the original receiver of the message is still in the network, has
90 not changed nickname, has not detached and resumed, and has not
91 reconnected to any other server, or, some other user has the same
93 5. the attacker is able to get the same client ID as the original
95 6. the original receiver still has the static key set for the same
96 remote client ID (for original sender's client ID).
98 All this is possible to happen though likelyhood is quite small. It
99 does illustrate how inappropriate the use of static keys is. (***DONE)
101 o The SILC public key identifier separator is ', ' not ','. The
102 whitespace is mandatory. (***DONE)
104 o Definition of EAP as new authentication method for connection auth
107 o Count limit to LIST command?
109 o Strict announces if Channel ID is different than on router? To not
110 allow any modes, topic, etc changes from server if the ID was wrong
111 initially? Meaning: riding with netsplits not possible since the
112 channel created during split will not enforce is modes to the
113 router. Or more liberal solution, like now? Read emails on
114 silc-users. (This is very old issue)
116 o The time values in STATS is 32-bits. After 2038 it's over 32-bits.
118 o Consider for future authenticated encryption modes.