[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 (file)
--- 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 @@ static inline u16 socket_type_to_security_class(int family, int type, int protoc
                                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 @@ static int selinux_parse_skb_ipv4(struct sk_buff *skb,
                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 @@ static int selinux_parse_skb_ipv6(struct sk_buff *skb,
                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 @@ static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, in
                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 @@ static int selinux_socket_connect(struct socket *sock, struct sockaddr *address,
                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 @@ static int selinux_socket_connect(struct socket *sock, struct sockaddr *address,
                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 @@ static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
                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 @@ static int selinux_ip_postroute_last_compat(struct sock *sk, struct net_device *
                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;

diff --git a/security/selinux/include/av_inherit.h b/security/selinux/include/av_inherit.h
index a68fdd5..8377a4b 100644 (file)
--- a/security/selinux/include/av_inherit.h
+++ b/security/selinux/include/av_inherit.h
@@ -30,3 +30,4 @@
    S_(SECCLASS_NETLINK_DNRT_SOCKET, socket, 0x00400000UL)
    S_(SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET, socket, 0x00400000UL)
    S_(SECCLASS_APPLETALK_SOCKET, socket, 0x00400000UL)
+   S_(SECCLASS_DCCP_SOCKET, socket, 0x00400000UL)

diff --git a/security/selinux/include/av_perm_to_string.h b/security/selinux/include/av_perm_to_string.h
index 09fc8a2..ad9fb2d 100644 (file)
--- a/security/selinux/include/av_perm_to_string.h
+++ b/security/selinux/include/av_perm_to_string.h
@@ -35,12 +35,16 @@
    S_(SECCLASS_NODE, NODE__RAWIP_RECV, "rawip_recv")
    S_(SECCLASS_NODE, NODE__RAWIP_SEND, "rawip_send")
    S_(SECCLASS_NODE, NODE__ENFORCE_DEST, "enforce_dest")
+   S_(SECCLASS_NODE, NODE__DCCP_RECV, "dccp_recv")
+   S_(SECCLASS_NODE, NODE__DCCP_SEND, "dccp_send")
    S_(SECCLASS_NETIF, NETIF__TCP_RECV, "tcp_recv")
    S_(SECCLASS_NETIF, NETIF__TCP_SEND, "tcp_send")
    S_(SECCLASS_NETIF, NETIF__UDP_RECV, "udp_recv")
    S_(SECCLASS_NETIF, NETIF__UDP_SEND, "udp_send")
    S_(SECCLASS_NETIF, NETIF__RAWIP_RECV, "rawip_recv")
    S_(SECCLASS_NETIF, NETIF__RAWIP_SEND, "rawip_send")
+   S_(SECCLASS_NETIF, NETIF__DCCP_RECV, "dccp_recv")
+   S_(SECCLASS_NETIF, NETIF__DCCP_SEND, "dccp_send")
    S_(SECCLASS_UNIX_STREAM_SOCKET, UNIX_STREAM_SOCKET__CONNECTTO, "connectto")
    S_(SECCLASS_UNIX_STREAM_SOCKET, UNIX_STREAM_SOCKET__NEWCONN, "newconn")
    S_(SECCLASS_UNIX_STREAM_SOCKET, UNIX_STREAM_SOCKET__ACCEPTFROM, "acceptfrom")
@@ -252,3 +256,7 @@
    S_(SECCLASS_KEY, KEY__LINK, "link")
    S_(SECCLASS_KEY, KEY__SETATTR, "setattr")
    S_(SECCLASS_KEY, KEY__CREATE, "create")
+   S_(SECCLASS_CONTEXT, CONTEXT__TRANSLATE, "translate")
+   S_(SECCLASS_CONTEXT, CONTEXT__CONTAINS, "contains")
+   S_(SECCLASS_DCCP_SOCKET, DCCP_SOCKET__NODE_BIND, "node_bind")
+   S_(SECCLASS_DCCP_SOCKET, DCCP_SOCKET__NAME_CONNECT, "name_connect")

diff --git a/security/selinux/include/av_permissions.h b/security/selinux/include/av_permissions.h
index 81f4f52..2de4b5f 100644 (file)
--- a/security/selinux/include/av_permissions.h
+++ b/security/selinux/include/av_permissions.h
@@ -312,6 +312,8 @@
 #define NODE__RAWIP_RECV                          0x00000010UL
 #define NODE__RAWIP_SEND                          0x00000020UL
 #define NODE__ENFORCE_DEST                        0x00000040UL
+#define NODE__DCCP_RECV                           0x00000080UL
+#define NODE__DCCP_SEND                           0x00000100UL
 
 #define NETIF__TCP_RECV                           0x00000001UL
 #define NETIF__TCP_SEND                           0x00000002UL
@@ -319,6 +321,8 @@
 #define NETIF__UDP_SEND                           0x00000008UL
 #define NETIF__RAWIP_RECV                         0x00000010UL
 #define NETIF__RAWIP_SEND                         0x00000020UL
+#define NETIF__DCCP_RECV                          0x00000040UL
+#define NETIF__DCCP_SEND                          0x00000080UL
 
 #define NETLINK_SOCKET__IOCTL                     0x00000001UL
 #define NETLINK_SOCKET__READ                      0x00000002UL
@@ -970,3 +974,31 @@
 #define KEY__LINK                                 0x00000010UL
 #define KEY__SETATTR                              0x00000020UL
 #define KEY__CREATE                               0x00000040UL
+
+#define CONTEXT__TRANSLATE                        0x00000001UL
+#define CONTEXT__CONTAINS                         0x00000002UL
+
+#define DCCP_SOCKET__IOCTL                        0x00000001UL
+#define DCCP_SOCKET__READ                         0x00000002UL
+#define DCCP_SOCKET__WRITE                        0x00000004UL
+#define DCCP_SOCKET__CREATE                       0x00000008UL
+#define DCCP_SOCKET__GETATTR                      0x00000010UL
+#define DCCP_SOCKET__SETATTR                      0x00000020UL
+#define DCCP_SOCKET__LOCK                         0x00000040UL
+#define DCCP_SOCKET__RELABELFROM                  0x00000080UL
+#define DCCP_SOCKET__RELABELTO                    0x00000100UL
+#define DCCP_SOCKET__APPEND                       0x00000200UL
+#define DCCP_SOCKET__BIND                         0x00000400UL
+#define DCCP_SOCKET__CONNECT                      0x00000800UL
+#define DCCP_SOCKET__LISTEN                       0x00001000UL
+#define DCCP_SOCKET__ACCEPT                       0x00002000UL
+#define DCCP_SOCKET__GETOPT                       0x00004000UL
+#define DCCP_SOCKET__SETOPT                       0x00008000UL
+#define DCCP_SOCKET__SHUTDOWN                     0x00010000UL
+#define DCCP_SOCKET__RECVFROM                     0x00020000UL
+#define DCCP_SOCKET__SENDTO                       0x00040000UL
+#define DCCP_SOCKET__RECV_MSG                     0x00080000UL
+#define DCCP_SOCKET__SEND_MSG                     0x00100000UL
+#define DCCP_SOCKET__NAME_BIND                    0x00200000UL
+#define DCCP_SOCKET__NODE_BIND                    0x00400000UL
+#define DCCP_SOCKET__NAME_CONNECT                 0x00800000UL

diff --git a/security/selinux/include/class_to_string.h b/security/selinux/include/class_to_string.h
index 24303b6..9f3ebb1 100644 (file)
--- a/security/selinux/include/class_to_string.h
+++ b/security/selinux/include/class_to_string.h
@@ -61,3 +61,5 @@
     S_("appletalk_socket")
     S_("packet")
     S_("key")
+    S_("context")
+    S_("dccp_socket")

diff --git a/security/selinux/include/flask.h b/security/selinux/include/flask.h
index 95887ae..67cef37 100644 (file)
--- a/security/selinux/include/flask.h
+++ b/security/selinux/include/flask.h
@@ -63,6 +63,8 @@
 #define SECCLASS_APPLETALK_SOCKET                        56
 #define SECCLASS_PACKET                                  57
 #define SECCLASS_KEY                                     58
+#define SECCLASS_CONTEXT                                 59
+#define SECCLASS_DCCP_SOCKET                             60
 
 /*
  * Security identifier indices for initial entities