Noticed that the test cases in ssl-opt.sh exercising the truncated HMAC
extension do not depend on MBEDTLS_SSL_TRUNCATED_HMAC being enabled in
config.h. This commit fixes this.
Previously, MAC validation for an incoming record proceeded as follows:
1) Make a copy of the MAC contained in the record;
2) Compute the expected MAC in place, overwriting the presented one;
3) Compare both.
This resulted in a record buffer overflow if truncated MAC was used, as in this
case the record buffer only reserved 10 bytes for the MAC, but the MAC
computation routine in 2) always wrote a full digest.
For specially crafted records, this could be used to perform a controlled write of
up to 6 bytes past the boundary of the heap buffer holding the record, thereby
corrupting the heap structures and potentially leading to a crash or remote code
execution.
This commit fixes this by making the following change:
1) Compute the expected MAC in a temporary buffer that has the size of the
underlying message digest.
2) Compare to this to the MAC contained in the record, potentially
restricting to the first 10 bytes if truncated HMAC is used.
A similar fix is applied to the encryption routine `ssl_encrypt_buf`.
This commit adds regression tests for the bug when we didn't parse the
Signature Algorithm extension when renegotiating. (By nature, this bug
affected only the server)
The tests check for the fallback hash (SHA1) in the server log to detect
that the Signature Algorithm extension hasn't been parsed at least in
one of the handshakes.
A more direct way of testing is not possible with the current test
framework, since the Signature Algorithm extension is parsed in the
first handshake and any corresponding debug message is present in the
logs.
The change modifies the template code in tests/suites/helpers.function
and tests/suites/main.function so that error messages are printed to
stdout instead of being discarded. This makes errors visible regardless
of the --verbose flag being passed or not to the test suite programs.
Add a test to ssl-opt.sh that parses the client and server debug
output and then checks that the Unix timestamp in the ServerHello
message is within acceptable bounds.
Extend the run_test function in ssl-opt.sh so that it accepts the -f
and -F options. These parameters take an argument which is the name of
a shell function that will be called by run_test and will be given the
client input and output debug log. The idea is that these functions are
defined by each test and they can be used to do some custom check
beyon those allowed by the pattern matching capabilities of the
run_test function.
Add a test case calling ssl_set_hostname twice to test_suite_ssl.
When run in CMake build mode ASan, this catches the current leak,
but will hopefully be fine with the new version.
The tests only work for a specific number for MBEDTLS_X509_MAX_INTERMEDIATE_CA
so the check has been changed to confirm the default value, and to show an error
otherwise.
The test for MBEDTLS_NO_UDBL_DIVISION wasn't preserving it's own config.h
for the next test.
Also added comments to ARM Compiler 6 tests to better explain them.
The X509 test suite assumes that MBEDTLS_X509_MAX_INTERMEDIATE_CA is below the
hardcoded threshold 20 used in the long certificate chain generating script
tests/data_files/dir-max/long.sh. This commit adds a compile-time check for
that.
Some tests in ssl-opt.sh assumes the value 8 for the maximal number
MBEDTLS_X509_MAX_INTERMEDIATE_CA of intermediate CA's. This commit adds a check
before conducting the respective tests.
If we didn't walk the whole chain, then there may be any kind of errors in the
part of the chain we didn't check, so setting all flags looks like the safe
thing to do.
Inspired by test code provided by Nicholas Wilson in PR #351.
The test will fail if someone sets MAX_INTERMEDIATE_CA to a value larger than
18 (default is 8), which is hopefully unlikely and can easily be fixed by
running long.sh again with a larger value if it ever happens.
Current behaviour is suboptimal as flags are not set, but currently the goal
is only to document/test existing behaviour.
This commit adds four tests to tests/ssl-opt.sh:
(1) & (2): Check behaviour of optional/required verification when the
trusted CA chain is empty.
(3) & (4): Check behaviour of optional/required verification when the
client receives a server certificate with an unsupported curve.
* gilles/IOTSSL-1330/development:
Changelog entry for the bug fixes
SSLv3: when refusing renegotiation, stop processing
Ignore failures when sending fatal alerts
Cleaned up double variable declaration
Code portability fix
Added changelog entry
Send TLS alerts in many more cases
Skip all non-executables in run-test-suites.pl
SSL tests: server requires auth, client has no certificate
Balanced braces across preprocessor conditionals
Support setting the ports on the command line
By default, keep allowing SHA-1 in key exchange signatures. Disabling
it causes compatibility issues, especially with clients that use
TLS1.2 but don't send the signature_algorithms extension.
SHA-1 is forbidden in certificates by default, since it's vulnerable
to offline collision-based attacks.
