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Mathy Vanhoef f024bdf115 net80211: mitigation against A-MSDU design flaw
Mitigate A-MSDU injection attacks by detecting if the destination address
of a subframe equals an RFC1042 (i.e., LLC/SNAP) header, and if so
dropping the complete A-MSDU frame.  This mitigates known attacks,
although new (unknown) aggregation-based attacks may remain possible.

This defense works because in A-MSDU aggregation injection attacks, a
normal encrypted Wi-Fi frame is turned into an A-MSDU frame. This means
the first 6 bytes of the first A-MSDU subframe correspond to an RFC1042
header. In other words, the destination MAC address of the first A-MSDU
subframe contains the start of an RFC1042 header during an aggregation
attack. We can detect this and thereby prevent this specific attack.

This relates to section 7.2 in the 2021 Usenix "FragAttacks" (Fragment
and Forge: Breaking Wi-Fi Through Frame Aggregation and Fragmentation)
paper.

Submitted by:	Mathy Vanhoef (Mathy.Vanhoef kuleuven.be)
Security:	CVE-2020-24588
PR:		256119
Differential Revision: https://reviews.freebsd.org/D30664
2021-09-30 14:50:45 +00:00
.cirrus-ci Cirrus-CI: add some timing info on pkg install failure 2021-08-04 15:02:00 -04:00
.github [skip ci] fix syntax in CODEOWNERS 2021-07-22 10:58:54 -06:00
bin hostname: avoid strcpy() overlap in -d flag handling 2021-09-25 00:03:50 -05:00
cddl dtrace.1: Document a couple of preprocessor-related options 2021-09-07 14:04:50 -04:00
contrib contrib/tzdata: import tzdata 2021b 2021-09-26 14:45:39 +08:00
crypto openssh: use global state for blacklist in grace_alarm_handler 2021-09-16 14:10:11 -04:00
etc Add support for jail.conf.d 2021-09-10 00:30:04 -05:00
gnu dialog: fix macro redefinition 2021-03-01 16:01:44 +01:00
include Add _Fork() 2021-08-03 21:19:32 +03:00
kerberos5 pkgbase: Create a FreeBSD-kerberos package 2021-09-07 10:23:14 +02:00
lib libpmc: add some AMD pmu counter aliases 2021-09-30 11:15:26 -03:00
libexec bluetooth: Remove stray btccc references 2021-09-29 21:58:27 -06:00
release EC2: Default to UEFI booting 2021-09-16 12:23:19 -07:00
rescue Fix building rescue/rescue when sanitizers are enabled 2021-07-06 12:18:30 +01:00
sbin pfctl: userspace adaptive syncookies configration 2021-09-29 15:11:54 +02:00
secure openssh: Add new source files to libssl 2021-09-10 00:56:24 +02:00
share bluetooth: complete removal of ng_h4 2021-09-29 20:00:02 -06:00
stand loader.efi: remove extra extern ST 2021-09-29 20:07:13 -06:00
sys net80211: mitigation against A-MSDU design flaw 2021-09-30 14:50:45 +00:00
targets Fix bootstrapping to actually build lldb-tblgen for later use 2021-08-24 15:04:25 +01:00
tests pf tests: Basic adaptive mode syncookie test 2021-09-29 15:42:01 +02:00
tools nemtap: lb app: Validate ihl field when hashing packet 2021-09-26 13:48:21 +00:00
usr.bin cmp: add -b, --print-bytes 2021-09-29 13:04:57 -05:00
usr.sbin bluetooth: remove hcseriald 2021-09-29 21:18:17 -06:00
.arcconfig Remove history.immutable from .arcconfig 2021-04-13 12:36:25 +01:00
.arclint arc lint: ignore /tests/ in chmod 2017-12-19 03:38:06 +00:00
.cirrus.yml Cirrus-CI: add a manually triggered arm64 task 2021-09-14 15:12:55 -04:00
.clang-format clang-format: Add bitset loop macros 2021-09-21 12:08:01 -04:00
.gitattributes Add a basic clang-format configuration file 2019-06-07 15:23:52 +00:00
.gitignore gitignore: Add .clangd and .ccls-cache 2021-06-04 16:56:08 +08:00
COPYRIGHT copyrights: Happy New Year 2021 2020-12-31 10:29:44 -05:00
LOCKS LOCKS: update current locks 2018-06-09 03:08:04 +00:00
MAINTAINERS [skip ci] volunteer to maintain POSIX AIO 2021-05-30 17:21:12 -06:00
Makefile Import tzdata 2021b 2021-09-26 14:35:07 +08:00
Makefile.inc1 Drop cloudabi 2021-09-22 00:18:44 +03:00
Makefile.libcompat Prefer MK_SSP=no to SSP_CFLAGS= 2021-08-04 15:23:22 -03:00
Makefile.sys.inc AUTO_OBJ: For all top-level targets enforce using an OBJDIR. 2017-12-05 21:29:47 +00:00
ObsoleteFiles.inc bluetooth: remove hcseriald 2021-09-29 21:18:17 -06:00
README.md Whitespace cleanup 2021-03-12 19:57:58 +08:00
RELNOTES RELNOTES: Add entries for KASAN and KMSAN 2021-08-11 13:08:36 -04:00
UPDATING UPDATING: new entry about dummynet 2021-09-24 14:21:25 +02:00

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