This makes the implementation less likely to provide useful timing
information to potential attackers from comparisons of information
received from a remote device and private material known only by the
authorized devices.
Signed-off-by: Jouni Malinen <j@w1.fi>
The padding validation was done on the last padding-length octets in the
buffer which misses the first padding octet (the last octet is the
padding length). Fix the starting offset for the comparison loop to get
the first octet verified. [Bug 420]
Signed-hostap: Jouni Malinen <j@w1.fi>
Return number of user input bytes from tlsv1_record_receive() to
move this detail into the proper record layer processing. In addition,
ignore unknown content types at record layer and allow processing to
continue after warning level TLS alerts to provide minimal workaround
for closure alerts.
Signed-hostap: Jouni Malinen <j@w1.fi>
Instead of using separate bad_record_mac and decryption_failed alerts,
use only bad_record_mac alert regardless of how the CBC decryption
failed. This provides less information to attackers that could modify
packets. In addition, instead of returning immediately on error, run
through the MAC check to make timing attacks more difficult.
When the received data will be decrypted, there is no need to first
copy it and then handle decryption in-place when decryption step can
take care of both operations.
TLS v1.0 and v1.1 RFCs were not exactly clear on the use of the
protocol version in record later. As such, accept any {03,xx} value
to remain compatible with existing implementations and new protocol
versions.
In addition, start ordering header file includes to be in more
consistent order: system header files, src/utils, src/*, same
directory as the *.c file.
