[SELinux]: Add support for DCCP
This patch implements SELinux kernel support for DCCP
(http://linux-net.osdl.org/index.php/DCCP), which is similar in
operation to TCP in terms of connected state between peers.
The SELinux support for DCCP is thus modeled on existing handling of
TCP.
A new DCCP socket class is introduced, to allow protocol
differentation. The permissions for this class inherit all of the
socket permissions, as well as the current TCP permissions (node_bind,
name_bind etc). IPv4 and IPv6 are supported, although labeled
networking is not, at this stage.
Patches for SELinux userspace are at:
http://people.redhat.com/jmorris/selinux/dccp/user/
I've performed some basic testing, and it seems to be working as
expected. Adding policy support is similar to TCP, the only real
difference being that it's a different protocol.
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 956137b..0cf9874 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -58,6 +58,7 @@
#include <linux/netlink.h>
#include <linux/tcp.h>
#include <linux/udp.h>
+#include <linux/dccp.h>
#include <linux/quota.h>
#include <linux/un.h> /* for Unix socket types */
#include <net/af_unix.h> /* for Unix socket types */
@@ -751,6 +752,8 @@
return SECCLASS_UDP_SOCKET;
else
return SECCLASS_RAWIP_SOCKET;
+ case SOCK_DCCP:
+ return SECCLASS_DCCP_SOCKET;
default:
return SECCLASS_RAWIP_SOCKET;
}
@@ -2944,6 +2947,22 @@
break;
}
+ case IPPROTO_DCCP: {
+ struct dccp_hdr _dccph, *dh;
+
+ if (ntohs(ih->frag_off) & IP_OFFSET)
+ break;
+
+ offset += ihlen;
+ dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
+ if (dh == NULL)
+ break;
+
+ ad->u.net.sport = dh->dccph_sport;
+ ad->u.net.dport = dh->dccph_dport;
+ break;
+ }
+
default:
break;
}
@@ -3004,6 +3023,18 @@
break;
}
+ case IPPROTO_DCCP: {
+ struct dccp_hdr _dccph, *dh;
+
+ dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
+ if (dh == NULL)
+ break;
+
+ ad->u.net.sport = dh->dccph_sport;
+ ad->u.net.dport = dh->dccph_dport;
+ break;
+ }
+
/* includes fragments */
default:
break;
@@ -3188,7 +3219,11 @@
case SECCLASS_UDP_SOCKET:
node_perm = UDP_SOCKET__NODE_BIND;
break;
-
+
+ case SECCLASS_DCCP_SOCKET:
+ node_perm = DCCP_SOCKET__NODE_BIND;
+ break;
+
default:
node_perm = RAWIP_SOCKET__NODE_BIND;
break;
@@ -3226,16 +3261,17 @@
return err;
/*
- * If a TCP socket, check name_connect permission for the port.
+ * If a TCP or DCCP socket, check name_connect permission for the port.
*/
isec = SOCK_INODE(sock)->i_security;
- if (isec->sclass == SECCLASS_TCP_SOCKET) {
+ if (isec->sclass == SECCLASS_TCP_SOCKET ||
+ isec->sclass == SECCLASS_DCCP_SOCKET) {
struct sock *sk = sock->sk;
struct avc_audit_data ad;
struct sockaddr_in *addr4 = NULL;
struct sockaddr_in6 *addr6 = NULL;
unsigned short snum;
- u32 sid;
+ u32 sid, perm;
if (sk->sk_family == PF_INET) {
addr4 = (struct sockaddr_in *)address;
@@ -3254,11 +3290,13 @@
if (err)
goto out;
+ perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
+ TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
+
AVC_AUDIT_DATA_INIT(&ad,NET);
ad.u.net.dport = htons(snum);
ad.u.net.family = sk->sk_family;
- err = avc_has_perm(isec->sid, sid, isec->sclass,
- TCP_SOCKET__NAME_CONNECT, &ad);
+ err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
if (err)
goto out;
}
@@ -3446,7 +3484,13 @@
node_perm = NODE__TCP_RECV;
recv_perm = TCP_SOCKET__RECV_MSG;
break;
-
+
+ case SECCLASS_DCCP_SOCKET:
+ netif_perm = NETIF__DCCP_RECV;
+ node_perm = NODE__DCCP_RECV;
+ recv_perm = DCCP_SOCKET__RECV_MSG;
+ break;
+
default:
netif_perm = NETIF__RAWIP_RECV;
node_perm = NODE__RAWIP_RECV;
@@ -3777,7 +3821,13 @@
node_perm = NODE__TCP_SEND;
send_perm = TCP_SOCKET__SEND_MSG;
break;
-
+
+ case SECCLASS_DCCP_SOCKET:
+ netif_perm = NETIF__DCCP_SEND;
+ node_perm = NODE__DCCP_SEND;
+ send_perm = DCCP_SOCKET__SEND_MSG;
+ break;
+
default:
netif_perm = NETIF__RAWIP_SEND;
node_perm = NODE__RAWIP_SEND;