diff options
author | Paul Jakma <paul.jakma@sun.com> | 2008-11-16 18:34:19 +0000 |
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committer | Paul Jakma <paul@quagga.net> | 2008-11-16 18:47:02 +0000 |
commit | 5d4b8cf2faba9f5386810a7c70837e5b7fae3572 (patch) | |
tree | ec89383f7bfd4684a0cde15648e5f00e8d2d8f7b /lib/checksum.h | |
parent | 41dc3488cf127a1e23333459a0c316ded67f7ff3 (diff) |
[lib] Switch Fletcher checksum back to old ospfd version
* lib/checksum.c: (fletcher_checksum) Switch the second phase of the checksum
back to the old ospfd logic.
The isisd-derived version:
a) is very hard to follow
b) had some kind of subtle bug that caused it be wrong when c0=0 and c1=254
(potentially fixable by doing the mods before adjusting x and y)
Additionally:
- explicitely cast expressions using non-internal variables to int, to ensure
the result is signed.
- defensively change the length argument to 'size_t', to ensure the code
works with that argument being unsigned..
Thanks to Joakim Tjernlund for the investigative work into this bug.
* tests/test-checksum.c: new file to exercise the checksum code.
Diffstat (limited to 'lib/checksum.h')
-rw-r--r-- | lib/checksum.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/lib/checksum.h b/lib/checksum.h index d3ce9302..da1d3cba 100644 --- a/lib/checksum.h +++ b/lib/checksum.h @@ -1,2 +1,2 @@ extern int in_cksum(void *, int); -extern u_int16_t fletcher_checksum(u_char * buffer, int len, u_int16_t offset); +extern u_int16_t fletcher_checksum(u_char *, const size_t len, const uint16_t offset); |