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e14eddeb97
This PR changes the way in which the SSL analyzer tracks the direction of connections. So far, the SSL analyzer assumed that the originator of a connection would send the client hello (and other associated client-side events), and that the responder would be the SSL servers. In some circumstances this is not true, and the initiator of a connection is the server, with the responder being the client. So far this confused some of the internal statekeeping logic and could lead to mis-parsing of extensions. This reversal of roles can happen in DTLS, if a connection uses STUN - and potentially in some StartTLS protocols. This PR tracks the direction of a TLS connection using the hello request, client hello and server hello handshake messages. Furthermore, it changes the SSL events from providing is_orig to providing is_client, where is_client is true for the client_side of a connection. Since the argument positioning in the event has not changed, old scripts will continue to work seamlessly - the new semantics are what everyone writing SSL scripts will have expected in any case. There is a new event that is raised when a connection is flipped. A weird is raised if a flip happens repeatedly. Addresses GH-2198.
21 lines
922 B
Text
21 lines
922 B
Text
# @TEST-EXEC: zeek -b -C -r $TRACES/tls/chrome-63.0.3211.0-canary-tls_experiment.pcap %INPUT
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# @TEST-EXEC: btest-diff ssl.log
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# @TEST-EXEC: btest-diff .stdout
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# This is a trace that uses a completely non-standard way of establishing TLS 1.3; this seems
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# to be an undocumented extension where the TLS version is negotiated via the server sending back
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# an supported_versions extension (which, according to the RFC is strictly prohibited).
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#
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# This only seems to happen with Chrome talking to google servers. We do not recognize this as
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# TLS 1.3, but we do not abort when encountering traffic like this.
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#
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# In the meantime this way of establishing TLS 1.3 was standardized. Still keeping the test even
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# though we parse this correctly now.
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@load base/protocols/ssl
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event ssl_extension(c: connection, is_client: bool, code: count, val: string)
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{
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if ( ! is_client && code == 43 )
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print bytestring_to_hexstr(val);
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}
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