zeek/src/analyzer/protocol/ssh/ssh-analyzer.pac

326 lines
9.4 KiB
JavaScript

%extern{
#include <cstdlib>
#include <vector>
#include <string>
#include "zeek/digest.h"
%}
%header{
zeek::VectorValPtr name_list_to_vector(const bytestring& nl);
const char* fingerprint_md5(const unsigned char* d);
%}
%code{
// Copied from IRC_Analyzer::SplitWords
zeek::VectorValPtr name_list_to_vector(const bytestring& nl)
{
auto vv = zeek::make_intrusive<zeek::VectorVal>(zeek::id::string_vec);
string name_list = std_str(nl);
if ( name_list.size() < 1 )
return vv;
unsigned int start = 0;
unsigned int split_pos = 0;
while ( name_list[start] == ',' )
{
++start;
++split_pos;
}
string word;
while ( (split_pos = name_list.find(',', start)) < name_list.size() )
{
word = name_list.substr(start, split_pos - start);
if ( word.size() > 0 && word[0] != ',' )
vv->Assign(vv->Size(), zeek::make_intrusive<zeek::StringVal>(word));
start = split_pos + 1;
}
// Add line end if needed.
if ( start < name_list.size() )
{
word = name_list.substr(start, name_list.size() - start);
vv->Assign(vv->Size(), zeek::make_intrusive<zeek::StringVal>(word));
}
return vv;
}
const char* fingerprint_md5(const unsigned char* d)
{
return zeek::util::fmt("%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:"
"%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x",
d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7],
d[8], d[9], d[10], d[11], d[12], d[13], d[14], d[15]);
}
%}
refine flow SSH_Flow += {
function proc_ssh_version(msg: SSH_Version): bool
%{
if ( ssh_client_version && ${msg.is_orig } )
{
zeek::BifEvent::enqueue_ssh_client_version(connection()->zeek_analyzer(),
connection()->zeek_analyzer()->Conn(),
to_stringval(${msg.version}));
}
else if ( ssh_server_version )
{
zeek::BifEvent::enqueue_ssh_server_version(connection()->zeek_analyzer(),
connection()->zeek_analyzer()->Conn(),
to_stringval(${msg.version}));
}
return true;
%}
function proc_ssh2_kexinit(msg: SSH2_KEXINIT): bool
%{
if ( ! ssh_capabilities )
return false;
auto result = zeek::make_intrusive<zeek::RecordVal>(zeek::BifType::Record::SSH::Capabilities);
result->Assign(0, name_list_to_vector(${msg.kex_algorithms.val}));
result->Assign(1, name_list_to_vector(${msg.server_host_key_algorithms.val}));
auto encryption_algs = zeek::make_intrusive<zeek::RecordVal>(zeek::BifType::Record::SSH::Algorithm_Prefs);
encryption_algs->Assign(0, name_list_to_vector(${msg.encryption_algorithms_client_to_server.val}));
encryption_algs->Assign(1, name_list_to_vector(${msg.encryption_algorithms_server_to_client.val}));
result->Assign(2, std::move(encryption_algs));
auto mac_algs = zeek::make_intrusive<zeek::RecordVal>(zeek::BifType::Record::SSH::Algorithm_Prefs);
mac_algs->Assign(0, name_list_to_vector(${msg.mac_algorithms_client_to_server.val}));
mac_algs->Assign(1, name_list_to_vector(${msg.mac_algorithms_server_to_client.val}));
result->Assign(3, std::move(mac_algs));
auto compression_algs = zeek::make_intrusive<zeek::RecordVal>(zeek::BifType::Record::SSH::Algorithm_Prefs);
compression_algs->Assign(0, name_list_to_vector(${msg.compression_algorithms_client_to_server.val}));
compression_algs->Assign(1, name_list_to_vector(${msg.compression_algorithms_server_to_client.val}));
result->Assign(4, std::move(compression_algs));
if ( ${msg.languages_client_to_server.len} || ${msg.languages_server_to_client.len} )
{
auto languages = zeek::make_intrusive<zeek::RecordVal>(zeek::BifType::Record::SSH::Algorithm_Prefs);
if ( ${msg.languages_client_to_server.len} )
languages->Assign(0, name_list_to_vector(${msg.languages_client_to_server.val}));
if ( ${msg.languages_server_to_client.len} )
languages->Assign(1, name_list_to_vector(${msg.languages_server_to_client.val}));
result->Assign(5, std::move(languages));
}
result->Assign(6, !${msg.is_orig});
zeek::BifEvent::enqueue_ssh_capabilities(connection()->zeek_analyzer(),
connection()->zeek_analyzer()->Conn(), to_stringval(${msg.cookie}),
result);
return true;
%}
function proc_ssh2_ecc_init(is_orig: bool): bool
%{
if ( ssh2_ecc_init )
{
zeek::BifEvent::enqueue_ssh2_ecc_init(connection()->zeek_analyzer(),
connection()->zeek_analyzer()->Conn(),
is_orig);
}
return true;
%}
function proc_ssh2_dh_gex_init(is_orig: bool): bool
%{
if ( ssh2_dh_gex_init )
{
zeek::BifEvent::enqueue_ssh2_dh_gex_init(connection()->zeek_analyzer(),
connection()->zeek_analyzer()->Conn(),
is_orig);
}
return true;
%}
function proc_ssh2_gss_init(is_orig: bool): bool
%{
if ( ssh2_gss_init )
{
zeek::BifEvent::enqueue_ssh2_gss_init(connection()->zeek_analyzer(),
connection()->zeek_analyzer()->Conn(),
is_orig);
}
return true;
%}
function proc_ssh2_rsa_secret(is_orig: bool): bool
%{
if ( ssh2_rsa_secret )
{
zeek::BifEvent::enqueue_ssh2_rsa_secret(connection()->zeek_analyzer(),
connection()->zeek_analyzer()->Conn(),
is_orig);
}
return true;
%}
function proc_ssh2_dh_gex_group(msg: SSH2_DH_GEX_GROUP): bool
%{
if ( ssh2_dh_server_params )
{
zeek::BifEvent::enqueue_ssh2_dh_server_params(connection()->zeek_analyzer(),
connection()->zeek_analyzer()->Conn(),
to_stringval(${msg.p.val}), to_stringval(${msg.g.val}));
}
return true;
%}
function proc_ssh2_ecc_key(q: bytestring, is_orig: bool): bool
%{
if ( ssh2_ecc_key )
{
zeek::BifEvent::enqueue_ssh2_ecc_key(connection()->zeek_analyzer(),
connection()->zeek_analyzer()->Conn(),
is_orig, to_stringval(q));
}
return true;
%}
function proc_ssh2_gss_error(msg: SSH2_GSS_ERROR): bool
%{
if ( ssh2_gss_error )
{
zeek::BifEvent::enqueue_ssh2_gss_error(connection()->zeek_analyzer(),
connection()->zeek_analyzer()->Conn(),
${msg.major_status}, ${msg.minor_status},
to_stringval(${msg.message.val}));
}
return true;
%}
function proc_ssh2_server_host_key(key: bytestring): bool
%{
if ( ssh_server_host_key )
{
unsigned char digest[MD5_DIGEST_LENGTH];
zeek::detail::internal_md5(${key}.data(), ${key}.length(), digest);
zeek::BifEvent::enqueue_ssh_server_host_key(connection()->zeek_analyzer(),
connection()->zeek_analyzer()->Conn(),
zeek::make_intrusive<zeek::StringVal>(fingerprint_md5(digest)));
}
if ( ssh2_server_host_key )
{
zeek::BifEvent::enqueue_ssh2_server_host_key(connection()->zeek_analyzer(),
connection()->zeek_analyzer()->Conn(),
to_stringval(${key}));
}
return true;
%}
function proc_ssh1_server_host_key(exp: bytestring, mod: bytestring): bool
%{
if ( ssh_server_host_key )
{
unsigned char digest[MD5_DIGEST_LENGTH];
auto ctx = zeek::detail::hash_init(zeek::detail::Hash_MD5);
// Fingerprint is calculated over concatenation of modulus + exponent.
zeek::detail::hash_update(ctx, ${mod}.data(), ${mod}.length());
zeek::detail::hash_update(ctx, ${exp}.data(), ${exp}.length());
zeek::detail::hash_final(ctx, digest);
zeek::BifEvent::enqueue_ssh_server_host_key(connection()->zeek_analyzer(),
connection()->zeek_analyzer()->Conn(),
zeek::make_intrusive<zeek::StringVal>(fingerprint_md5(digest)));
}
if ( ssh1_server_host_key )
{
zeek::BifEvent::enqueue_ssh1_server_host_key(connection()->zeek_analyzer(),
connection()->zeek_analyzer()->Conn(),
to_stringval(${mod}),
to_stringval(${exp}));
}
return true;
%}
function proc_newkeys(): bool
%{
connection()->zeek_analyzer()->AnalyzerConfirmation();
return true;
%}
function get_kex_length(v: int, packet_length: uint32): int
%{
switch (v) {
case SSH1:
return packet_length + 4 + 8 - (packet_length % 8);
case SSH2:
return packet_length + 4;
default:
return 1; //currently causes the rest of the packet to dump
}
%}
};
refine typeattr SSH_Version += &let {
proc: bool = $context.flow.proc_ssh_version(this);
};
refine typeattr SSH2_KEXINIT += &let {
proc: bool = $context.flow.proc_ssh2_kexinit(this);
};
refine typeattr SSH1_Message += &let {
proc_newkeys: bool = $context.flow.proc_newkeys() &if(msg_type == SSH_CMSG_SESSION_KEY);
};
refine typeattr SSH2_Message += &let {
proc_newkeys: bool = $context.flow.proc_newkeys() &if(msg_type == MSG_NEWKEYS);
};
refine typeattr SSH2_DH_GEX_REPLY += &let {
proc: bool = $context.flow.proc_ssh2_server_host_key(k_s.val);
};
refine typeattr SSH2_GSS_HOSTKEY += &let {
proc: bool = $context.flow.proc_ssh2_server_host_key(k_s.val);
};
refine typeattr SSH2_GSS_ERROR += &let {
proc: bool = $context.flow.proc_ssh2_gss_error(this);
};
refine typeattr SSH2_DH_GEX_GROUP += &let {
proc: bool = $context.flow.proc_ssh2_dh_gex_group(this);
};
refine typeattr SSH2_ECC_REPLY += &let {
proc_k: bool = $context.flow.proc_ssh2_server_host_key(k_s.val);
proc_q: bool = $context.flow.proc_ssh2_ecc_key(q_s.val, is_orig);
};
refine typeattr SSH2_ECC_INIT += &let {
proc: bool = $context.flow.proc_ssh2_ecc_key(q_c.val, is_orig);
proc_init: bool = $context.flow.proc_ssh2_ecc_init(is_orig);
};
refine typeattr SSH2_DH_GEX_INIT += &let {
proc_init: bool = $context.flow.proc_ssh2_dh_gex_init(is_orig);
};
refine typeattr SSH2_GSS_INIT += &let {
proc_init: bool = $context.flow.proc_ssh2_gss_init(is_orig);
};
refine typeattr SSH2_RSA_SECRET += &let {
proc_init: bool = $context.flow.proc_ssh2_rsa_secret(is_orig);
};
refine typeattr SSH1_PUBLIC_KEY += &let {
proc: bool = $context.flow.proc_ssh1_server_host_key(host_key_exp.val, host_key_mod.val);
};