]> git.ipfire.org Git - ipfire-2.x.git/blame - src/patches/igmpproxy-003-Restrict-igmp-reports-for-downstream-interfaces-wrt-.patch
core115: Include captive portal in updater
[ipfire-2.x.git] / src / patches / igmpproxy-003-Restrict-igmp-reports-for-downstream-interfaces-wrt-.patch
CommitLineData
4bc434b8
JL
1From 65f777e7f66b55239d935c1cf81bb5abc0f6c89f Mon Sep 17 00:00:00 2001
2From: Grinch <grinch79@users.sourceforge.net>
3Date: Sun, 16 Aug 2009 19:58:26 +0500
4Subject: [PATCH] Restrict igmp reports for downstream interfaces (wrt #2833339)
5
6atm all igmp membership reports are forwarded to the upstream interface.
7Unfortunately some ISP Providers restrict some multicast groups (esp. those
8that are defined as local link groups and that are not supposed to be
9forwarded to the wan, i.e 224.0.0.0/24). Therefore there should be some
10kind of black oder whitelisting.
11As whitelisting can be accomplished quite easy I wrote a litte patch, which
12is attached to this request.
13---
14 doc/igmpproxy.conf.5.in | 19 +++++++++++++++++++
15 src/config.c | 23 ++++++++++++++++++++++-
16 src/igmpproxy.h | 1 +
17 src/request.c | 20 ++++++++++++++++----
18 4 files changed, 58 insertions(+), 5 deletions(-)
19
20diff --git a/doc/igmpproxy.conf.5.in b/doc/igmpproxy.conf.5.in
21index a4ea7d0..56efa22 100644
22--- a/doc/igmpproxy.conf.5.in
23+++ b/doc/igmpproxy.conf.5.in
24@@ -116,6 +116,25 @@ This is especially useful for the upstream interface, since the source for multi
25 traffic is often from a remote location. Any number of altnet parameters can be specified.
26 .RE
27
28+.B whitelist
29+.I networkaddr
30+.RS
31+Defines a whitelist for multicast groups. The network address must be in the following
32+format 'a.b.c.d/n'. If you want to allow one single group use a network mask of /32,
33+i.e. 'a.b.c.d/32'.
34+
35+By default all multicast groups are allowed on any downstream interface. If at least one
36+whitelist entry is defined, all igmp membership reports for not explicitly whitelisted
37+multicast groups will be ignored and therefore not be served by igmpproxy. This is especially
38+useful, if your provider does only allow a predefined set of multicast groups. These whitelists
39+are only obeyed by igmpproxy itself, they won't prevent any other igmp client running on the
40+same machine as igmpproxy from requesting 'unallowed' multicast groups.
41+
42+You may specify as many whitelist entries as needed. Although you should keep it as simple as
43+possible, as this list is parsed for every membership report and therefore this increases igmp
44+response times. Often used or large groups should be defined first, as parsing ends as soon as
45+a group matches an entry.
46+.RE
47
48 .SH EXAMPLE
49 ## Enable quickleave
50diff --git a/src/config.c b/src/config.c
51index 5a96ce0..d72619f 100644
52--- a/src/config.c
53+++ b/src/config.c
54@@ -46,6 +46,9 @@ struct vifconfig {
55
56 // Keep allowed nets for VIF.
57 struct SubnetList* allowednets;
58+
59+ // Allowed Groups
60+ struct SubnetList* allowedgroups;
61
62 // Next config in list...
63 struct vifconfig* next;
64@@ -202,6 +205,8 @@ void configureVifs() {
65 // Insert the configured nets...
66 vifLast->next = confPtr->allowednets;
67
68+ Dp->allowedgroups = confPtr->allowedgroups;
69+
70 break;
71 }
72 }
73@@ -215,7 +220,7 @@ void configureVifs() {
74 */
75 struct vifconfig *parsePhyintToken() {
76 struct vifconfig *tmpPtr;
77- struct SubnetList **anetPtr;
78+ struct SubnetList **anetPtr, **agrpPtr;
79 char *token;
80 short parseError = 0;
81
82@@ -239,6 +244,7 @@ struct vifconfig *parsePhyintToken() {
83 tmpPtr->threshold = 1;
84 tmpPtr->state = IF_STATE_DOWNSTREAM;
85 tmpPtr->allowednets = NULL;
86+ tmpPtr->allowedgroups = NULL;
87
88 // Make a copy of the token to store the IF name
89 tmpPtr->name = strdup( token );
90@@ -248,6 +254,7 @@ struct vifconfig *parsePhyintToken() {
91
92 // Set the altnet pointer to the allowednets pointer.
93 anetPtr = &tmpPtr->allowednets;
94+ agrpPtr = &tmpPtr->allowedgroups;
95
96 // Parse the rest of the config..
97 token = nextConfigToken();
98@@ -266,6 +273,20 @@ struct vifconfig *parsePhyintToken() {
99 anetPtr = &(*anetPtr)->next;
100 }
101 }
102+ else if(strcmp("whitelist", token)==0) {
103+ // Whitelist
104+ token = nextConfigToken();
105+ my_log(LOG_DEBUG, 0, "Config: IF: Got whitelist token %s.", token);
106+
107+ *agrpPtr = parseSubnetAddress(token);
108+ if(*agrpPtr == NULL) {
109+ parseError = 1;
110+ my_log(LOG_WARNING, 0, "Unable to parse subnet address.");
111+ break;
112+ } else {
113+ agrpPtr = &(*agrpPtr)->next;
114+ }
115+ }
116 else if(strcmp("upstream", token)==0) {
117 // Upstream
118 my_log(LOG_DEBUG, 0, "Config: IF: Got upstream token.");
119diff --git a/src/igmpproxy.h b/src/igmpproxy.h
120index 4dabd1c..0de7791 100644
121--- a/src/igmpproxy.h
122+++ b/src/igmpproxy.h
123@@ -145,6 +145,7 @@ struct IfDesc {
124 short Flags;
125 short state;
126 struct SubnetList* allowednets;
127+ struct SubnetList* allowedgroups;
128 unsigned int robustness;
129 unsigned char threshold; /* ttl limit */
130 unsigned int ratelimit;
131diff --git a/src/request.c b/src/request.c
132index e3589f6..89b91de 100644
133--- a/src/request.c
134+++ b/src/request.c
135@@ -82,10 +82,22 @@ void acceptGroupReport(uint32_t src, uint32_t group, uint8_t type) {
136 my_log(LOG_DEBUG, 0, "Should insert group %s (from: %s) to route table. Vif Ix : %d",
137 inetFmt(group,s1), inetFmt(src,s2), sourceVif->index);
138
139- // The membership report was OK... Insert it into the route table..
140- insertRoute(group, sourceVif->index);
141-
142-
143+ // If we don't have a whitelist we insertRoute and done
144+ if(sourceVif->allowedgroups == NULL)
145+ {
146+ insertRoute(group, sourceVif->index);
147+ return;
148+ }
149+ // Check if this Request is legit on this interface
150+ struct SubnetList *sn;
151+ for(sn = sourceVif->allowedgroups; sn != NULL; sn = sn->next)
152+ if((group & sn->subnet_mask) == sn->subnet_addr)
153+ {
154+ // The membership report was OK... Insert it into the route table..
155+ insertRoute(group, sourceVif->index);
156+ return;
157+ }
158+ my_log(LOG_INFO, 0, "The group address %s may not be requested from this interface. Ignoring.", inetFmt(group, s1));
159 } else {
160 // Log the state of the interface the report was recieved on.
161 my_log(LOG_INFO, 0, "Mebership report was recieved on %s. Ignoring.",
162--
1631.7.2.5
164