Description
openedon Jul 24, 2024
Describe the bug
The net_tls_connection
connection table can possibly have incorrect values for cipher_suite_name
when connecting via TLS 1.3.
Looking at the code, it is returning the requested cipher suite, while the docs say it is the "Negotiated cipher suite". This would be true up until this change made by the Go team for TLS 1.3 (and remains true for TLS 1.2 and below). This causes the net plugin to report that ciphers such as TLS_CHACHA20_POLY1305_SHA256
were able to complete a handshake, when in fact they were not, and Go automatically negotiated another cipher that the server supports such as TLS_AES_128_GCM_SHA256
to make the connection. This is largely a big problem for compliance environments where reports are needed for compliant TLS ciphers for production web servers.
Steampipe version (steampipe -v
)
v0.23.2
Plugin version (steampipe plugin list
)
v0.12.0
To reproduce
Place a Linux web server with openssl in FIPS mode and run a simple Nginx server. It will not support TLS_CHACHA20_POLY1305_SHA256
as its not FIPS validated. This can be verified with openssl ciphers -v
Run the steampipe query
select
address,
version,
cipher_suite_name,
handshake_completed
from
net_tls_connection
where
address = 'YOUR_NGINX_SERVER:443'
and handshake_completed;
and notice results such as:
+-----------------+----------+---------------------------------------+-----------------+---------------------+----------------+
| address | version | cipher_suite_name | cipher_suite_id | handshake_completed | alpn_supported |
+-----------------+----------+---------------------------------------+-----------------+---------------------+----------------+
| 10.0.84.132:443 | TLS v1.3 | TLS_AES_256_GCM_SHA384 | 0x1302 | true | true |
| 10.0.84.132:443 | TLS v1.2 | TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 | 0xc02f | true | true |
| 10.0.84.132:443 | TLS v1.3 | TLS_AES_128_GCM_SHA256 | 0x1301 | true | true |
| 10.0.84.132:443 | TLS v1.3 | TLS_CHACHA20_POLY1305_SHA256 | 0x1303 | true | true |
| 10.0.84.132:443 | TLS v1.2 | TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 | 0xc030 | true | true |
+-----------------+----------+---------------------------------------+-----------------+---------------------+----------------+
Where steampipe is claiming it connected to that server which doesn't support TLS_CHACHA20_POLY1305_SHA256
using the TLS_CHACHA20_POLY1305_SHA256
cipher.
Expected behavior
Either replace the cipher_suite_name
and ciper_suite_id
with the real negotiated cipher instead of the requested one or add a new column for a negotiated cipher to distinguish the difference.
Additional context
Helpful Go test code for this issue.
https://go.dev/blog/tls-cipher-suites
golang/go#29349
Activity