We don't implement anonymous key exchanges, and we don't intend to, so it can
never happen that an unauthenticated server requests a certificate from us.
After the record contents are decompressed, in_len is no longer
accessed directly, only in_msglen is accessed. in_len is only read by
ssl_parse_record_header() which happens before ssl_prepare_record_contents().
This is also made clear by the fact that in_len is not touched after
decrypting anyway, so if it was accessed after that it would be wrong unless
decryption is used - as this is not the case, it show in_len is not accessed.
Previously it was failing with errors about headers not found, which is
suboptimal in terms of clarity. Now give a clean error with pointer to the
documentation.
Do the checks in the .c files rather than check_config.h as it keeps them
closer to the platform-specific implementations.
* IOTSSL-621-PotentialIntegerOverflow:
Add precision about exploitability in ChangeLog
Add Changelog entry for current branch
Included tests for the overflow
armar doesn't understand the syntax without dash. OTOH, the syntax with dash
is the only one specified by POSIX, and it's accepted by GNU ar, BSD ar (as
bundled with OS X) and armar, so it looks like the most portable syntax.
fixes#386
* yanesca/iss309:
Improved on the previous fix and added a test case to cover both types of carries.
Removed recursion from fix#309.
Improved on the fix of #309 and extended the test to cover subroutines.
Tests and fix added for #309 (inplace mpi doubling).
See for example page 8 of
http://csrc.nist.gov/publications/nistpubs/800-38D/SP-800-38D.pdf
The previous constant probably came from a typo as it was 2^26 - 2^5 instead
of 2^36 - 2^5. Clearly the intention was to allow for a constant bigger than
2^32 as the ull suffix and cast to uint64_t show.
fixes#362
By looking just at that test, it looks like 2 + dn_size could overflow. In
fact that can't happen as that would mean we've read a CA cert of size is too
big to be represented by a size_t.
However, it's best for code to be more obviously free of overflow without
having to reason about the bigger picture.
In case an entry with the given OID already exists in the list passed to
mbedtls_asn1_store_named_data() and there is not enough memory to allocate
room for the new value, the existing entry will be freed but the preceding
entry in the list will sill hold a pointer to it. (And the following entries
in the list are no longer reachable.) This results in memory leak or a double
free.
The issue is we want to leave the list in a consistent state on allocation
failure. (We could add a warning that the list is left in inconsistent state
when the function returns NULL, but behaviour changes that require more care
from the user are undesirable, especially in a stable branch.)
The chosen solution is a bit inefficient in that there is a time where both
blocks are allocated, but at least it's safe and this should trump efficiency
here: this code is only used for generating certificates, which is unlikely to
be done on very constrained devices, or to be in the critical loop of
anything. Also, the sizes involved should be fairly small anyway.
fixes#367
When the peer retransmits a flight with many record in the same datagram, and
we already saw one of the records in that datagram, we used to drop the whole
datagram, resulting in interoperability failure (spurious handshake timeouts,
due to ignoring record retransmitted by the peer) with some implementations
(issues with Chrome were reported).
So in those cases, we want to only drop the current record, and look at the
following records (if any) in the same datagram. OTOH, this is not something
we always want to do, as sometime the header of the current record is not
reliable enough.
This commit introduces a new return code for ssl_parse_header() that allows to
distinguish if we should drop only the current record or the whole datagram,
and uses it in mbedtls_ssl_read_record()
fixes#345
Remove check on the pathLenConstraint value when looking for a parent to the
EE cert, as the constraint is on the number of intermediate certs below the
parent, and that number is always 0 at that point, so the constraint is always
satisfied.
The check was actually off-by-one, which caused valid chains to be rejected
under the following conditions:
- the parent certificate is not a trusted root, and
- it has pathLenConstraint == 0 (max_pathlen == 1 in our representation)
fixes#280
* iotssl-519-asn1write-overflows-restricted:
Fix other int casts in bounds checking
Fix other occurrences of same bounds check issue
Fix potential buffer overflow in asn1write
* iotssl-515-max-pathlen:
Add Changelog entries for this branch
Fix a style issue
Fix whitespace at EOL issues
Use symbolic constants in test data
Fixed pathlen contraint enforcement.
Additional corner cases for testing pathlen constrains. Just in case.
Added test case for pathlen constrains in intermediate certificates