ieee802154: add dgram sockopts for security control

Allow datagram sockets to override the security settings of the device
they send from on a per-socket basis. Requires CAP_NET_ADMIN or
CAP_NET_RAW, since raw sockets can send arbitrary packets anyway.

Signed-off-by: Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/af_ieee802154.h b/include/net/af_ieee802154.h
index f79ae2a..085940f 100644 (file)
--- a/include/net/af_ieee802154.h
+++ b/include/net/af_ieee802154.h
@@ -57,6 +57,14 @@ struct sockaddr_ieee802154 {
 /* get/setsockopt */
 #define SOL_IEEE802154 0
 
-#define WPAN_WANTACK   0
+#define WPAN_WANTACK           0
+#define WPAN_SECURITY          1
+#define WPAN_SECURITY_LEVEL    2
+
+#define WPAN_SECURITY_DEFAULT  0
+#define WPAN_SECURITY_OFF      1
+#define WPAN_SECURITY_ON       2
+
+#define WPAN_SECURITY_LEVEL_DEFAULT    (-1)
 
 #endif

diff --git a/net/ieee802154/dgram.c b/net/ieee802154/dgram.c
index 76c7725..4f0ed87 100644 (file)
--- a/net/ieee802154/dgram.c
+++ b/net/ieee802154/dgram.c
@@ -21,6 +21,7 @@
  * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
  */
 
+#include <linux/capability.h>
 #include <linux/net.h>
 #include <linux/module.h>
 #include <linux/if_arp.h>
@@ -47,6 +48,10 @@ struct dgram_sock {
        unsigned int bound:1;
        unsigned int connected:1;
        unsigned int want_ack:1;
+       unsigned int secen:1;
+       unsigned int secen_override:1;
+       unsigned int seclevel:3;
+       unsigned int seclevel_override:1;
 };
 
 static inline struct dgram_sock *dgram_sk(const struct sock *sk)
@@ -264,6 +269,11 @@ static int dgram_sendmsg(struct kiocb *iocb, struct sock *sk,
                dst_addr = ro->dst_addr;
        }
 
+       cb->secen = ro->secen;
+       cb->secen_override = ro->secen_override;
+       cb->seclevel = ro->seclevel;
+       cb->seclevel_override = ro->seclevel_override;
+
        err = dev_hard_header(skb, dev, ETH_P_IEEE802154, &dst_addr,
                              ro->bound ? &ro->src_addr : NULL, size);
        if (err < 0)
@@ -427,6 +437,20 @@ static int dgram_getsockopt(struct sock *sk, int level, int optname,
        case WPAN_WANTACK:
                val = ro->want_ack;
                break;
+       case WPAN_SECURITY:
+               if (!ro->secen_override)
+                       val = WPAN_SECURITY_DEFAULT;
+               else if (ro->secen)
+                       val = WPAN_SECURITY_ON;
+               else
+                       val = WPAN_SECURITY_OFF;
+               break;
+       case WPAN_SECURITY_LEVEL:
+               if (!ro->seclevel_override)
+                       val = WPAN_SECURITY_LEVEL_DEFAULT;
+               else
+                       val = ro->seclevel;
+               break;
        default:
                return -ENOPROTOOPT;
        }
@@ -442,6 +466,7 @@ static int dgram_setsockopt(struct sock *sk, int level, int optname,
                    char __user *optval, unsigned int optlen)
 {
        struct dgram_sock *ro = dgram_sk(sk);
+       struct net *net = sock_net(sk);
        int val;
        int err = 0;
 
@@ -457,6 +482,47 @@ static int dgram_setsockopt(struct sock *sk, int level, int optname,
        case WPAN_WANTACK:
                ro->want_ack = !!val;
                break;
+       case WPAN_SECURITY:
+               if (!ns_capable(net->user_ns, CAP_NET_ADMIN) &&
+                   !ns_capable(net->user_ns, CAP_NET_RAW)) {
+                       err = -EPERM;
+                       break;
+               }
+
+               switch (val) {
+               case WPAN_SECURITY_DEFAULT:
+                       ro->secen_override = 0;
+                       break;
+               case WPAN_SECURITY_ON:
+                       ro->secen_override = 1;
+                       ro->secen = 1;
+                       break;
+               case WPAN_SECURITY_OFF:
+                       ro->secen_override = 1;
+                       ro->secen = 0;
+                       break;
+               default:
+                       err = -EINVAL;
+                       break;
+               }
+               break;
+       case WPAN_SECURITY_LEVEL:
+               if (!ns_capable(net->user_ns, CAP_NET_ADMIN) &&
+                   !ns_capable(net->user_ns, CAP_NET_RAW)) {
+                       err = -EPERM;
+                       break;
+               }
+
+               if (val < WPAN_SECURITY_LEVEL_DEFAULT ||
+                   val > IEEE802154_SCF_SECLEVEL_ENC_MIC128) {
+                       err = -EINVAL;
+               } else if (val == WPAN_SECURITY_LEVEL_DEFAULT) {
+                       ro->seclevel_override = 0;
+               } else {
+                       ro->seclevel_override = 1;
+                       ro->seclevel = val;
+               }
+               break;
        default:
                err = -ENOPROTOOPT;
                break;