Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Additional security section on fragmentation reassembly attacks #444

Merged
merged 9 commits into from Apr 24, 2017
Merged

Additional security section on fragmentation reassembly attacks #444

Changes from all commits
Commits
Show all changes
9 commits
Select commit Hold shift + click to select a range
cdbfb64
Additional security section on fragmentation reassembly attacks
huitema Apr 19, 2017
dade254
Update draft-ietf-quic-transport.md
huitema Apr 19, 2017
6a0337c
Removing trailing spaces on some of changed lines
huitema Apr 19, 2017
d244484
Simplifying the text, per Martin's review
huitema Apr 20, 2017
46f293c
Simplifying the mitigation text
huitema Apr 21, 2017
040a5fe
And fixing a typo.
huitema Apr 21, 2017
a168b3b
STREAM frames.
huitema Apr 21, 2017
31872b3
Can lead
huitema Apr 21, 2017
b47c030
MAY -> could
huitema Apr 21, 2017
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
19 changes: 19 additions & 0 deletions draft-ietf-quic-transport.md
View file
Open in desktop
Expand Up @@ -2697,6 +2697,25 @@ also be forward-secure encrypted. Since the attacker will not have the forward
secure key, the attacker will not be able to generate forward-secure encrypted
packets with ACK frames.

## Stream Fragmentation and Reassembly Attacks

An adversarial endpoint might intentionally fragment the data on
stream buffers in order to cause disproportionate memory commitment.
The adversarial endpoint would open a stream,
and send some STREAM frames containing arbitrary
fragments of the stream content.

The attack is mitigated if flow control windows correspond to
available memory. However, some receivers will over-commit memory and advertise
flow control offsets in the aggregate that exceed actual available memory.
The over-commitment strategy can lead to better performance when
endpoints are well behaved, but renders endpoints vulnerable to
the stream fragmentation attack.

QUIC deployments SHOULD provide mitigations against the stream fragmentation
attack. Mitigations could consist of avoiding over-committing memory, delaying
reassembly of STREAM frames, implementing heuristics based on the
age and duration of reassembly holes, or some combination.

# IANA Considerations

Expand Down