Blowfish-CTR mode incorrect

• Reporter: (Anonymous)
• Owner: doda
• Type: Bugs
• Status: Closed
• Component: TTSSH
• MileStone: Tera Term 4.91 (closed)
• Priority: 5 - Medium
• Severity: 5 - Medium
• Resolution: Fixed
• File: None

Details Reply

blowfish-ctr in TeraTerm defaults to using a 128-bit key rather than a 256-bit key. See https://tools.ietf.org/html/rfc4344 page 4 which states:

The "blowfish-ctr" method uses Blowfish with 256-bit keys SCHNEIER. The block size is 8 bytes. (Note that "blowfish-cbc" from RFC4253 uses 128-bit keys.)

If I manually change my SSH server to use 128-bit keys with blowfish-ctr, a connection is correctly made. PuTTY 0.67 does not have this problem and correctly uses 256-bit keys.

Ticket History (3/5 Histories)

2016-05-06 04:46 Updated by: None

• New Ticket "Blowfish-CTR mode incorrect" created

2016-05-06 18:43 Updated by: doda

• Owner Update from (None) to doda
• Milestone Update from (None) to Tera Term 4.91 (closed)
• Component Update from Tera Term to TTSSH
• Resolution Update from None to Accepted

2016-05-07 03:11 Updated by: doda

• Resolution Update from Accepted to Fixed

2016-05-09 10:22 Updated by: doda

Comment Reply

fixed. Thanks!

https://ttssh2.osdn.jp/snapshot/snapshot-20160509.zip

2016-05-31 23:00 Updated by: (del#1144)

• Ticket Close date is changed to 2016-05-31 23:00
• Status Update from Open to Closed