This PR fixes a few bugs in `sslv2_sockets()`. The main issue is that a server may not send the entire ServerHello in a single packet. If it doesn't and the full response is being parsed (i.e., certificate and list of ciphers), then `parse_sslv2_serverhello()` will encounter errors, since it assumes that it has the entire ServerHello. This PR compares the length of the response to the length of the ServerHello as specified in the first two bytes of the response and requests more data from the server if the response appears incomplete.
This PR also modifies `parse_sslv2_serverhello()` to check for more errors. It compares the length of the response it has been provided to the specified length (`$v2_hello_length`) and returns an error if the response is shorter than `$v2_hello_length` and the full response is supposed to be parsed. It will also check whether there was an error in converting the certificate from DER to PEM format and will return an error if there was (and it will suppress the error message).
If `determine_tls_extensions()` does not create a temporary file (`$TEMPDIR/$NODEIP.determine_tls_extensions.txt`) then `run_server_defaults()` will display error messages when an attempt is made to copy this file or to search (grep) it. This may happen if `$OPTIMAL_PROTO` is `-ssl2` or if `determine_tls_extensions()` uses sockets and `parse_tls_serverhello()` encountered an error and did not create a temporary file (`$TEMPDIR/$NODEIP.parse_tls_serverhello.txt`). This PR fixes this by only trying to copy and search `$TEMPDIR/$NODEIP.determine_tls_extensions.txt` is `$OPTIMAL_PROTO` is not `-ssl2` and `determine_tls_extensions()` was successful (return value 0).
In response to your request in #572, this PR provides a starting point for addressing #120. It adds code to `run_logjam()` to try connecting to the server using any cipher that uses an ephemeral DH key. If successful, it gets the server's ephemeral key (in OpenSSL's PEM format) and then extracts the prime from the key and places it in `$dh_p`. So, all that needs to be done at this point is to compare `$dh_p` against a set of "bad" primes. I'm not sure if I'll be able to work on that part soon, so if someone else has the time, that would be great.
I actually found the `-msg` option easy to use. I moved the code in `parse_tls_serverhello()` that extracts the DH ephemeral public key from the ServerKeyExchange message into a separate function. Then, if using OpenSSL with the `-msg` option, I extract the ServerKeyExchange message from `$TMPFILE` and call this new function to extract the key and convert it to PEM format. That way the new code in `run_logjam()` can use either `$OPENSSL` or `tls_sockets()`.
This PR changes `run_http2()` so that it uses `tls_sockets()` rather than failing, if `$OPENSSL` does not support the `-alpn` option. If `$OPENSSL` supports the `-alpn` option (or if `$SSL_NATIVE` is true), then this PR has no effect.
In a few places testssl.sh tries to determine $OPENSSL s_client's capabilities by calling `$OPENSSL s_client` without specifying a host to which to connect. For example:
```
$OPENSSL s_client -no_ssl2 2>&1
```
This idea is that `$OPENSSL s_client` should reveal something about its capabilities without actually trying to connect to a host.
This works in most cases. However, the manual pages for s_client states:
```
-connect host:port
This specifies the host and optional port to connect to. If not specified then an attempt is made to connect to the local host on port 4433.
```
So, the above call is actually trying to connect to the local host on port 4433. If the local host is running `$OPENSSL s_server`, then `$OPENSSL s_server` will by default be listening on port 4433, and the connection attempt will most likely succeed. Since the `OPENSSL s_client` command does not include a `< /dev/null`, the `OPENSSL s_client` will just hang waiting for additional input.
Adding `-connect x` to the `$OPENSSL s_client` prevents $OPENSSL from trying to connect to a host, but seems to still provide the necessary information about OpenSSL's capabilities.
This PR adds ",exp" to the bits column when `run_rc4()` is run in the "--wide" mode and the cipher is an export cipher. This makes the wide mode of `run_rc4()` align with other functions, such as `run_allciphers()`.
When `test_just_one()` uses `neat_list()` with a cipher that is not available and that uses DH for key exchange, the columns do not line up correctly. `test_just_one()` adds "TBD" in gray to "DH", and while `neat_list()` tries to adjust for the presence of color codes, it doesn't seem to correctly handle the gray color code here.
Rather than try to fix this in `neat_list()`, I propose to just remove the "TBD". Adding it is inconsistent with other functions (like `run_allciphers()`), and it seems inappropriate, since there is nothing "to be determined," as the cipher suite isn't supported by the server.
If adding "TBD" were appropriate anywhere, it would seem to be in cases in which the server does support the cipher, but the number of bits in the ephemeral key couldn't be determined because the version of OpenSSL being used can't show DH/ECDH bits. (Not that I'm proposing this. I think the one-line warning, "(Your $OPENSSL cannot show DH/ECDH bits)", is enough.
Here is an example of `test_just_one()` with some ciphers not supported by the server that use DH key exchange:
```
Testing single cipher with word pattern "CAMELLIA" (ignore case)
Hexcode Cipher Suite Name (OpenSSL) KeyExch. Encryption Bits Cipher Suite Name (RFC)
---------------------------------------------------------------------------------------------------------------------------
xc077 ECDHE-RSA-CAMELLIA256-SHA384 ECDH TBD Camellia 256 TLS_ECDHE_RSA_WITH_CAMELLIA_256_CBC_SHA384 not a/v
xc073 ECDHE-ECDSA-CAMELLIA256-SHA384 ECDH TBD Camellia 256 TLS_ECDHE_ECDSA_WITH_CAMELLIA_256_CBC_SHA384 not a/v
xc4 DHE-RSA-CAMELLIA256-SHA256 DH TBD Camellia 256 TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA256 not a/v
xc3 DHE-DSS-CAMELLIA256-SHA256 DH TBD Camellia 256 TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA256 not a/v
xc2 DH-RSA-CAMELLIA256-SHA256 DH/RSA Camellia 256 TLS_DH_RSA_WITH_CAMELLIA_256_CBC_SHA256 not a/v
xc1 DH-DSS-CAMELLIA256-SHA256 DH/DSS Camellia 256 TLS_DH_DSS_WITH_CAMELLIA_256_CBC_SHA256 not a/v
x88 DHE-RSA-CAMELLIA256-SHA DH 2048 Camellia 256 TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA available
x87 DHE-DSS-CAMELLIA256-SHA DH TBD Camellia 256 TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA not a/v
x86 DH-RSA-CAMELLIA256-SHA DH/RSA Camellia 256 TLS_DH_RSA_WITH_CAMELLIA_256_CBC_SHA not a/v
x85 DH-DSS-CAMELLIA256-SHA DH/DSS Camellia 256 TLS_DH_DSS_WITH_CAMELLIA_256_CBC_SHA not a/v
xc5 ADH-CAMELLIA256-SHA256 DH TBD Camellia 256 TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA256 not a/v
x89 ADH-CAMELLIA256-SHA DH TBD Camellia 256 TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA not a/v
xc079 ECDH-RSA-CAMELLIA256-SHA384 ECDH/RSA Camellia 256 TLS_ECDH_RSA_WITH_CAMELLIA_256_CBC_SHA384 not a/v
xc075 ECDH-ECDSA-CAMELLIA256-SHA384 ECDH/ECDSA Camellia 256 TLS_ECDH_ECDSA_WITH_CAMELLIA_256_CBC_SHA384 not a/v
xc0 CAMELLIA256-SHA256 RSA Camellia 256 TLS_RSA_WITH_CAMELLIA_256_CBC_SHA256 not a/v
x84 CAMELLIA256-SHA RSA Camellia 256 TLS_RSA_WITH_CAMELLIA_256_CBC_SHA not a/v
xc076 ECDHE-RSA-CAMELLIA128-SHA256 ECDH TBD Camellia 128 TLS_ECDHE_RSA_WITH_CAMELLIA_128_CBC_SHA256 not a/v
xc072 ECDHE-ECDSA-CAMELLIA128-SHA256 ECDH TBD Camellia 128 TLS_ECDHE_ECDSA_WITH_CAMELLIA_128_CBC_SHA256 not a/v
xbe DHE-RSA-CAMELLIA128-SHA256 DH TBD Camellia 128 TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA256 not a/v
xbd DHE-DSS-CAMELLIA128-SHA256 DH TBD Camellia 128 TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA256 not a/v
xbc DH-RSA-CAMELLIA128-SHA256 DH/RSA Camellia 128 TLS_DH_RSA_WITH_CAMELLIA_128_CBC_SHA256 not a/v
xbb DH-DSS-CAMELLIA128-SHA256 DH/DSS Camellia 128 TLS_DH_DSS_WITH_CAMELLIA_128_CBC_SHA256 not a/v
x45 DHE-RSA-CAMELLIA128-SHA DH 2048 Camellia 128 TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA available
x44 DHE-DSS-CAMELLIA128-SHA DH TBD Camellia 128 TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA not a/v
x43 DH-RSA-CAMELLIA128-SHA DH/RSA Camellia 128 TLS_DH_RSA_WITH_CAMELLIA_128_CBC_SHA not a/v
x42 DH-DSS-CAMELLIA128-SHA DH/DSS Camellia 128 TLS_DH_DSS_WITH_CAMELLIA_128_CBC_SHA not a/v
xbf ADH-CAMELLIA128-SHA256 DH TBD Camellia 128 TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA256 not a/v
x46 ADH-CAMELLIA128-SHA DH TBD Camellia 128 TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA not a/v
xc078 ECDH-RSA-CAMELLIA128-SHA256 ECDH/RSA Camellia 128 TLS_ECDH_RSA_WITH_CAMELLIA_128_CBC_SHA256 not a/v
xc074 ECDH-ECDSA-CAMELLIA128-SHA256 ECDH/ECDSA Camellia 128 TLS_ECDH_ECDSA_WITH_CAMELLIA_128_CBC_SHA256 not a/v
xba CAMELLIA128-SHA256 RSA Camellia 128 TLS_RSA_WITH_CAMELLIA_128_CBC_SHA256 not a/v
x41 CAMELLIA128-SHA RSA Camellia 128 TLS_RSA_WITH_CAMELLIA_128_CBC_SHA not a/v
```
David Cooper
Dirk Wetter
Todd Swatling
AlGreed