When writing a private EC key, use a constant size for the private
value, as specified in RFC 5915. Previously, the value was written
as an ASN.1 INTEGER, which caused the size of the key to leak
about 1 bit of information on average, and could cause the value to be
1 byte too large for the output buffer.
Add pk_write test cases where the ASN.1 INTEGER encoding of the
private value does not have the mandatory size for the OCTET STRING
that contains the value.
ec_256_long_prv.pem is a random secp256r1 private key, selected so
that the private value is >= 2^255, i.e. the top bit of the first byte
is set (which would cause the INTEGER encoding to have an extra
leading 0 byte).
ec_521_short_prv.pem is a random secp521r1 private key, selected so
that the private value is < 2^518, i.e. the first byte is zero and the
top bit of the second byte is 0 (which would cause the INTEGER
encoding to have one less 0 byte at the start).
`mbedtls_ssl_get_record_expansion()` is supposed to return the maximum
difference between the size of a protected record and the size of the
encapsulated plaintext.
Previously, it did not correctly estimate the maximum record expansion
in case of CBC ciphersuites in (D)TLS versions 1.1 and higher, in which
case the ciphertext is prefixed by an explicit IV.
This commit fixes this bug. Fixes#1914.
sprintf( (char *) buf, "%s\r\n", base );
Above code generates Wformat-overflow warning since both buf and base
are of same size. buf should be sizeof( base ) + characters added in
the format. In this case format 2 bytes for "\r\n".
In `mbedtls_ccm_self_test()`, enforce input and output
buffers sent to the ccm API to be contigous and aligned,
by copying the test vectors to buffers on the stack.
- in x509_profile_check_pk_alg
- in x509_profile_check_md_alg
- in x509_profile_check_key
and in ssl_cli.c : unsigned char gets promoted to signed integer
In ecp_mul_comb(), if (!p_eq_g && grp->T == NULL) and then ecp_precompute_comb() fails (which can
happen due to OOM), then the new array of points T will be leaked (as it's newly allocated, but
hasn't been asigned to grp->T yet).
Symptom was a memory leak in ECDHE key exchange under low memory conditions.