SCTP: Allow ADD_IP to work with AUTH for backward compatibility.
This patch adds a tunable that will allow ADD_IP to work without
AUTH for backward compatibility. The default value is off since
the default value for ADD_IP is off as well. People who need
to use ADD-IP with older implementations take risks of connection
hijacking and should consider upgrading or turning this tunable on.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 41f1039..44f2672 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -212,6 +212,7 @@
/* Flag to indicate if addip is enabled. */
int addip_enable;
+ int addip_noauth_enable;
/* Flag to indicate if PR-SCTP is enabled. */
int prsctp_enable;
@@ -249,6 +250,7 @@
#define sctp_local_addr_list (sctp_globals.local_addr_list)
#define sctp_local_addr_lock (sctp_globals.addr_list_lock)
#define sctp_addip_enable (sctp_globals.addip_enable)
+#define sctp_addip_noauth (sctp_globals.addip_noauth_enable)
#define sctp_prsctp_enable (sctp_globals.prsctp_enable)
#define sctp_auth_enable (sctp_globals.auth_enable)
diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index eaad5c5..013e3d3 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -262,10 +262,14 @@
*/
asoc->peer.sack_needed = 1;
- /* Assume that the peer recongizes ASCONF until reported otherwise
- * via an ERROR chunk.
+ /* Assume that the peer will tell us if he recognizes ASCONF
+ * as part of INIT exchange.
+ * The sctp_addip_noauth option is there for backward compatibilty
+ * and will revert old behavior.
*/
asoc->peer.asconf_capable = 0;
+ if (sctp_addip_noauth)
+ asoc->peer.asconf_capable = 1;
/* Create an input queue. */
sctp_inq_init(&asoc->base.inqueue);
diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index 40c1a47..ecfab03 100644
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -1179,6 +1179,7 @@
/* Disable ADDIP by default. */
sctp_addip_enable = 0;
+ sctp_addip_noauth = 0;
/* Enable PR-SCTP by default. */
sctp_prsctp_enable = 1;
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 2ff3a3d..43e8de1 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -2137,8 +2137,10 @@
/* If the peer claims support for ADD-IP without support
* for AUTH, disable support for ADD-IP.
+ * Do this only if backward compatible mode is turned off.
*/
- if (asoc->peer.asconf_capable && !asoc->peer.auth_capable) {
+ if (!sctp_addip_noauth &&
+ (asoc->peer.asconf_capable && !asoc->peer.auth_capable)) {
asoc->peer.addip_disabled_mask |= (SCTP_PARAM_ADD_IP |
SCTP_PARAM_DEL_IP |
SCTP_PARAM_SET_PRIMARY);
diff --git a/net/sctp/sysctl.c b/net/sctp/sysctl.c
index 0669778..da4f157 100644
--- a/net/sctp/sysctl.c
+++ b/net/sctp/sysctl.c
@@ -263,6 +263,15 @@
.proc_handler = &proc_dointvec,
.strategy = &sysctl_intvec
},
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "addip_noauth_enable",
+ .data = &sctp_addip_noauth,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec,
+ .strategy = &sysctl_intvec
+ },
{ .ctl_name = 0 }
};