changed configuration file to accomodate SNI in a cleaner way

This commit is contained in:
Yves Rutschle 2015-07-17 15:04:04 +02:00
parent 77ef29358d
commit 8fdaf6eb08
6 changed files with 68 additions and 51 deletions

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@ -5,6 +5,11 @@ vNEXT:
Added support for RFC4366 SNI
(Travis Burtrum)
Changed configuration file format: 'probe' field is
no longer required, 'name' field can now contain
'sni' or 'regex', with corresponding options (see
example.org)
v1.17: 09MAR2015
Support RFC5952-style IPv6 addresses, e.g. [::]:443.

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@ -19,11 +19,11 @@ listen:
protocols:
(
{ name: "ssh"; service: "ssh"; host: "localhost"; port: "22"; probe: "builtin"; },
{ name: "openvpn"; host: "localhost"; port: "1194"; probe: "builtin"; },
{ name: "xmpp"; host: "localhost"; port: "5222"; probe: "builtin"; },
{ name: "http"; host: "localhost"; port: "80"; probe: "builtin"; },
{ name: "ssl"; host: "localhost"; port: "443"; probe: "builtin"; },
{ name: "anyprot"; host: "localhost"; port: "443"; probe: "builtin"; }
{ name: "ssh"; service: "ssh"; host: "localhost"; port: "22"; },
{ name: "openvpn"; host: "localhost"; port: "1194"; },
{ name: "xmpp"; host: "localhost"; port: "5222"; },
{ name: "http"; host: "localhost"; port: "80"; },
{ name: "ssl"; host: "localhost"; port: "443"; },
{ name: "anyprot"; host: "localhost"; port: "443"; }
);

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@ -23,31 +23,48 @@ listen:
# List of protocols
#
# Each protocol entry consists of:
# name: name of the protocol
# name: name of the probe. These are listed on the command
# line (ssh -?), plus 'regex', 'sni' and 'timeout'.
# service: (optional) libwrap service name (see hosts_access(5))
# host: host name to connect that protocol
# port: port number to connect that protocol
# probe: "builtin" or a list of regular expressions
# (can be left out, e.g. to use with on-timeout)
# host, port: where to connect when this probe succeeds
#
# Probe-specific options:
# sni:
# sni_hotnames: list of FQDN for that target
# regex:
# regex_patterns: list of patterns to match for
# that target.
#
# sslh will try each probe in order they are declared, and
# connect to the first that matches.
#
# You can specify several of 'regex' and 'sni'.
protocols:
(
{ name: "ssh"; service: "ssh"; host: "localhost"; port: "22"; probe: "builtin"; },
{ name: "sni"; host: "localhost"; port: "993"; probe: "builtin"; sni_hostnames: [ "imap.example.org", "imap.example.com" ]; },
{ name: "openvpn"; host: "localhost"; port: "1194"; probe: [ "^\x00[\x0D-\xFF]$", "^\x00[\x0D-\xFF]\x38" ]; },
{ name: "xmpp"; host: "localhost"; port: "5222"; probe: [ "jabber" ]; },
{ name: "http"; host: "localhost"; port: "80"; probe: "builtin"; },
{ name: "ssl"; host: "localhost"; port: "443"; probe: [ "" ]; },
{ name: "ssh"; service: "ssh"; host: "localhost"; port: "22"; },
{ name: "http"; host: "localhost"; port: "80"; },
{ name: "sni"; host: "localhost"; port: "993"; sni_hostnames: [ "mail.rutschle.net", "mail.englishintoulouse.com" ]; },
{ name: "sni"; host: "localhost"; port: "xmpp-client"; sni_hostnames: [ "im.rutschle.net", "im.englishintoulouse.com" ]; },
# OpenVPN
{ name: "regex"; host: "localhost"; port: "1194"; regex_patterns: [ "^\x00[\x0D-\xFF]$", "^\x00[\x0D-\xFF]\x38" ]; },
# Jabber
{ name: "regex"; host: "localhost"; port: "5222"; regex_patterns: [ "jabber" ]; },
# Catch-all
{ name: "regex"; host: "localhost"; port: "443"; regex_patterns: [ "" ]; },
# Where to connect in case of timeout (defaults to ssh)
{ name: "timeout"; service: "daytime"; host: "localhost"; port: "daytime"; }
);
# Optionally, specify to which protocol to connect in case
# of timeout (defaults to "ssh").
# You can timeout to any arbitrary address by setting a
# protocol with no probe, as is the case with this example.
# You can timeout to any arbitrary address by setting an
# entry in 'protocols' named "timeout".
# This enables you to set a tcpd service name for this
# protocol too.
on-timeout: "timeout";

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@ -233,11 +233,13 @@ static int is_sni_protocol(const char *p, int len, struct proto *proto)
/* Assume does not match */
valid_tls = PROBE_NEXT;
for (sni_hostname = proto->data; *sni_hostname; sni_hostname++)
for (sni_hostname = proto->data; *sni_hostname; sni_hostname++) {
fprintf(stderr, "matching [%s] with [%s]\n", hostname, *sni_hostname);
if(!strcmp(hostname, *sni_hostname)) {
valid_tls = PROBE_MATCH;
break;
}
}
free(hostname);
return valid_tls;
@ -365,6 +367,11 @@ T_PROBE* get_probe(const char* description) {
if (!strcmp(description, "sni"))
return is_sni_protocol;
/* Special case of "timeout" is allowed as a probe name in the
* configuration file even though it's not really a probe */
if (!strcmp(description, "timeout"))
return is_true;
return NULL;
}

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@ -249,7 +249,7 @@ static void setup_sni_hostnames(struct proto *p, config_setting_t* sni_hostnames
#ifdef LIBCONFIG
static int config_protocols(config_t *config, struct proto **prots)
{
config_setting_t *setting, *prot, *probes, *sni_hostnames;
config_setting_t *setting, *prot, *patterns, *sni_hostnames;
const char *hostname, *port, *name;
int i, num_prots;
struct proto *p, *prev = NULL;
@ -273,34 +273,26 @@ static int config_protocols(config_t *config, struct proto **prots)
resolve_split_name(&(p->saddr), hostname, port);
p->probe = get_probe(name);
if (!p->probe) {
fprintf(stderr, "line %d: %s: probe unknown\n", config_setting_source_line(prot), name);
exit(1);
}
probes = config_setting_get_member(prot, "probe");
if (probes) {
if (config_setting_is_array(probes)) {
/* If 'probe' is an array, setup a regex probe using the
* array of strings as pattern */
setup_regex_probe(p, probes);
} else {
/* if 'probe' is 'builtin', set the probe to the
* appropriate builtin protocol */
if (!strcmp(config_setting_get_string(probes), "builtin")) {
p->probe = get_probe(name);
if (!p->probe) {
fprintf(stderr, "%s: no builtin probe for this protocol\n", name);
exit(1);
}
} else {
fprintf(stderr, "%s: illegal probe name\n", name);
exit(1);
}
/* Probe-specific options: regex patterns */
if (!strcmp(name, "regex")) {
patterns = config_setting_get_member(prot, "regex_patterns");
if (patterns && config_setting_is_array(patterns)) {
setup_regex_probe(p, patterns);
}
}
sni_hostnames = config_setting_get_member(prot, "sni_hostnames");
if (sni_hostnames && config_setting_is_array(sni_hostnames)) {
setup_sni_hostnames(p, sni_hostnames);
/* Probe-specific options: SNI hostnames */
if (!strcmp(name, "sni")) {
sni_hostnames = config_setting_get_member(prot, "sni_hostnames");
if (sni_hostnames && config_setting_is_array(sni_hostnames)) {
setup_sni_hostnames(p, sni_hostnames);
}
}
}
}

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@ -51,14 +51,10 @@ and the list of protocols).
The configuration file makes it possible to specify
protocols using regular expressions: a list of regular
expressions is given as the I<probe> parameter, and if the
expressions is given as the I<regex_patterns> parameter, and if the
first packet received from the client matches any of these
expressions, B<sslh> connects to that protocol.
Alternatively, the I<probe> parameter can be set to
"builtin", to use the compiled probes which are much faster
than regular expressions.
=head2 Probing protocols
When receiving an incoming connection, B<sslh> will read the