Remove BIO_CTRL_DGRAM_MTU_EXCEEDED retry in dtls1_do_write.

The retry doesn't actually work when we're sending a non-initial fragment; the
s->init_off != 0 block will get re-run each iteration through and continually
prepend headers. It can also infinite loop if the BIO reports
BIO_CTRL_DGRAM_MTU_EXCEEDED but either fails to report an MTU or reports an MTU
that always rounds up to the minimum. See upstream's
d3d9eef31661633f5b003a9e115c1822f79d1870.

WebRTC doesn't participate in any of the MTU logic and inherits the default
MTU, so just remove it for now.

Change-Id: Ib2ed2ba016b7c229811741fb7369c015ba0b551f
Reviewed-on: https://boringssl-review.googlesource.com/2827
Reviewed-by: Adam Langley <agl@google.com>
1 file changed