The vtls layer now checks the return value, so it is no longer necessary
to abort if a random number cannot be provided by NSS. This also fixes
the following Coverity report:
Error: FORWARD_NULL (CWE-476):
lib/vtls/nss.c:1918: var_compare_op: Comparing "data" to null implies that "data" might be null.
lib/vtls/nss.c:1923: var_deref_model: Passing null pointer "data" to "Curl_failf", which dereferences it.
lib/sendf.c:154:3: deref_parm: Directly dereferencing parameter "data".
Correctly check for memcmp() return value (it returns 0 if the strings match).
This is not really important, since curl is going to use http/1.1 anyway, but
it's still a bug I guess.
Carrying on from commit 037cd0d991, removed the following unimplemented
instances of curlssl_close_all():
Curl_axtls_close_all()
Curl_darwinssl_close_all()
Curl_cyassl_close_all()
Curl_gskit_close_all()
Curl_gtls_close_all()
Curl_nss_close_all()
Curl_polarssl_close_all()
curl_schannel.h:123: warning: right-hand operand of comma expression
has no effect
Some instances of the curlssl_close_all() function were declared with a
void return type whilst others as int. The schannel version returned
CURLE_NOT_BUILT_IN and others simply returned zero, but in all cases the
return code was ignored by the calling function Curl_ssl_close_all().
For the time being and to keep the internal API consistent, changed all
declarations to use a void return type.
To reduce code we might want to consider removing the unimplemented
versions and use a void #define like schannel does.
- Remove SSLv3 from SSL default in darwinssl, schannel, cyassl, nss,
openssl effectively making the default TLS 1.x. axTLS is not affected
since it supports only TLS, and gnutls is not affected since it already
defaults to TLS 1.x.
- Update CURLOPT_SSLVERSION doc
To force each backend implementation to really attempt to provide proper
random. If a proper random function is missing, then we can explicitly
make use of the default one we use when TLS support is missing.
This commit makes sure it works for darwinssl, gnutls, nss and openssl.
when using --http2 one can now selectively disable NPN or ALPN with
--no-alpn and --no-npn. for now honored with NSS only.
TODO: honor this option with GnuTLS and OpenSSL
SSL_ENABLE_ALPN can be used for preprocessor ALPN feature detection,
but not SSL_NEXT_PROTO_SELECTED, since it is an enum value and not a
preprocessor macro.
