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Diffstat (limited to 'net')
-rw-r--r--net/can/Kconfig13
-rw-r--r--net/can/bcm.c12
-rw-r--r--net/can/gw.c74
-rw-r--r--net/can/raw.c8
4 files changed, 80 insertions, 27 deletions
diff --git a/net/can/Kconfig b/net/can/Kconfig
index 03200699d274..a15c0e0d1fc7 100644
--- a/net/can/Kconfig
+++ b/net/can/Kconfig
@@ -16,10 +16,11 @@ menuconfig CAN
If you want CAN support you should say Y here and also to the
specific driver for your controller(s) below.
+if CAN
+
config CAN_RAW
tristate "Raw CAN Protocol (raw access with CAN-ID filtering)"
- depends on CAN
- default N
+ default y
---help---
The raw CAN protocol option offers access to the CAN bus via
the BSD socket API. You probably want to use the raw socket in
@@ -29,8 +30,7 @@ config CAN_RAW
config CAN_BCM
tristate "Broadcast Manager CAN Protocol (with content filtering)"
- depends on CAN
- default N
+ default y
---help---
The Broadcast Manager offers content filtering, timeout monitoring,
sending of RTR frames, and cyclic CAN messages without permanent user
@@ -42,8 +42,7 @@ config CAN_BCM
config CAN_GW
tristate "CAN Gateway/Router (with netlink configuration)"
- depends on CAN
- default N
+ default y
---help---
The CAN Gateway/Router is used to route (and modify) CAN frames.
It is based on the PF_CAN core infrastructure for msg filtering and
@@ -53,3 +52,5 @@ config CAN_GW
by the netlink configuration interface known e.g. from iptables.
source "drivers/net/can/Kconfig"
+
+endif
diff --git a/net/can/bcm.c b/net/can/bcm.c
index 969b7cdff59d..ccc27b9e8384 100644
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -54,6 +54,7 @@
#include <linux/skbuff.h>
#include <linux/can.h>
#include <linux/can/core.h>
+#include <linux/can/skb.h>
#include <linux/can/bcm.h>
#include <linux/slab.h>
#include <net/sock.h>
@@ -256,10 +257,13 @@ static void bcm_can_tx(struct bcm_op *op)
return;
}
- skb = alloc_skb(CFSIZ, gfp_any());
+ skb = alloc_skb(CFSIZ + sizeof(struct can_skb_priv), gfp_any());
if (!skb)
goto out;
+ skb_reserve(skb, sizeof(struct can_skb_priv));
+ ((struct can_skb_priv *)(skb->head))->ifindex = dev->ifindex;
+
memcpy(skb_put(skb, CFSIZ), cf, CFSIZ);
/* send with loopback */
@@ -1199,11 +1203,12 @@ static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk)
if (!ifindex)
return -ENODEV;
- skb = alloc_skb(CFSIZ, GFP_KERNEL);
-
+ skb = alloc_skb(CFSIZ + sizeof(struct can_skb_priv), GFP_KERNEL);
if (!skb)
return -ENOMEM;
+ skb_reserve(skb, sizeof(struct can_skb_priv));
+
err = memcpy_fromiovec(skb_put(skb, CFSIZ), msg->msg_iov, CFSIZ);
if (err < 0) {
kfree_skb(skb);
@@ -1216,6 +1221,7 @@ static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk)
return -ENODEV;
}
+ ((struct can_skb_priv *)(skb->head))->ifindex = dev->ifindex;
skb->dev = dev;
skb->sk = sk;
err = can_send(skb, 1); /* send with loopback */
diff --git a/net/can/gw.c b/net/can/gw.c
index 574dda78eb0f..acdd4656cc3b 100644
--- a/net/can/gw.c
+++ b/net/can/gw.c
@@ -42,6 +42,7 @@
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
+#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/rcupdate.h>
@@ -52,19 +53,31 @@
#include <linux/skbuff.h>
#include <linux/can.h>
#include <linux/can/core.h>
+#include <linux/can/skb.h>
#include <linux/can/gw.h>
#include <net/rtnetlink.h>
#include <net/net_namespace.h>
#include <net/sock.h>
-#define CAN_GW_VERSION "20101209"
-static __initconst const char banner[] =
- KERN_INFO "can: netlink gateway (rev " CAN_GW_VERSION ")\n";
+#define CAN_GW_VERSION "20130117"
+#define CAN_GW_NAME "can-gw"
MODULE_DESCRIPTION("PF_CAN netlink gateway");
MODULE_LICENSE("Dual BSD/GPL");
MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
-MODULE_ALIAS("can-gw");
+MODULE_ALIAS(CAN_GW_NAME);
+
+#define CGW_MIN_HOPS 1
+#define CGW_MAX_HOPS 6
+#define CGW_DEFAULT_HOPS 1
+
+static unsigned int max_hops __read_mostly = CGW_DEFAULT_HOPS;
+module_param(max_hops, uint, S_IRUGO);
+MODULE_PARM_DESC(max_hops,
+ "maximum " CAN_GW_NAME " routing hops for CAN frames "
+ "(valid values: " __stringify(CGW_MIN_HOPS) "-"
+ __stringify(CGW_MAX_HOPS) " hops, "
+ "default: " __stringify(CGW_DEFAULT_HOPS) ")");
static HLIST_HEAD(cgw_list);
static struct notifier_block notifier;
@@ -118,6 +131,7 @@ struct cgw_job {
struct rcu_head rcu;
u32 handled_frames;
u32 dropped_frames;
+ u32 deleted_frames;
struct cf_mod mod;
union {
/* CAN frame data source */
@@ -338,15 +352,40 @@ static void can_can_gw_rcv(struct sk_buff *skb, void *data)
struct sk_buff *nskb;
int modidx = 0;
- /* do not handle already routed frames - see comment below */
- if (skb_mac_header_was_set(skb))
+ /*
+ * Do not handle CAN frames routed more than 'max_hops' times.
+ * In general we should never catch this delimiter which is intended
+ * to cover a misconfiguration protection (e.g. circular CAN routes).
+ *
+ * The Controller Area Network controllers only accept CAN frames with
+ * correct CRCs - which are not visible in the controller registers.
+ * According to skbuff.h documentation the csum_start element for IP
+ * checksums is undefined/unsued when ip_summed == CHECKSUM_UNNECESSARY.
+ * Only CAN skbs can be processed here which already have this property.
+ */
+
+#define cgw_hops(skb) ((skb)->csum_start)
+
+ BUG_ON(skb->ip_summed != CHECKSUM_UNNECESSARY);
+
+ if (cgw_hops(skb) >= max_hops) {
+ /* indicate deleted frames due to misconfiguration */
+ gwj->deleted_frames++;
return;
+ }
if (!(gwj->dst.dev->flags & IFF_UP)) {
gwj->dropped_frames++;
return;
}
+ /* is sending the skb back to the incoming interface not allowed? */
+ if (!(gwj->flags & CGW_FLAGS_CAN_IIF_TX_OK) &&
+ skb_headroom(skb) == sizeof(struct can_skb_priv) &&
+ (((struct can_skb_priv *)(skb->head))->ifindex ==
+ gwj->dst.dev->ifindex))
+ return;
+
/*
* clone the given skb, which has not been done in can_rcv()
*
@@ -363,15 +402,8 @@ static void can_can_gw_rcv(struct sk_buff *skb, void *data)
return;
}
- /*
- * Mark routed frames by setting some mac header length which is
- * not relevant for the CAN frames located in the skb->data section.
- *
- * As dev->header_ops is not set in CAN netdevices no one is ever
- * accessing the various header offsets in the CAN skbuffs anyway.
- * E.g. using the packet socket to read CAN frames is still working.
- */
- skb_set_mac_header(nskb, 8);
+ /* put the incremented hop counter in the cloned skb */
+ cgw_hops(nskb) = cgw_hops(skb) + 1;
nskb->dev = gwj->dst.dev;
/* pointer to modifiable CAN frame */
@@ -472,6 +504,11 @@ static int cgw_put_job(struct sk_buff *skb, struct cgw_job *gwj, int type,
goto cancel;
}
+ if (gwj->deleted_frames) {
+ if (nla_put_u32(skb, CGW_DELETED, gwj->deleted_frames) < 0)
+ goto cancel;
+ }
+
/* check non default settings of attributes */
if (gwj->mod.modtype.and) {
@@ -771,6 +808,7 @@ static int cgw_create_job(struct sk_buff *skb, struct nlmsghdr *nlh,
gwj->handled_frames = 0;
gwj->dropped_frames = 0;
+ gwj->deleted_frames = 0;
gwj->flags = r->flags;
gwj->gwtype = r->gwtype;
@@ -895,7 +933,11 @@ static int cgw_remove_job(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
static __init int cgw_module_init(void)
{
- printk(banner);
+ /* sanitize given module parameter */
+ max_hops = clamp_t(unsigned int, max_hops, CGW_MIN_HOPS, CGW_MAX_HOPS);
+
+ pr_info("can: netlink gateway (rev " CAN_GW_VERSION ") max_hops=%d\n",
+ max_hops);
cgw_cache = kmem_cache_create("can_gw", sizeof(struct cgw_job),
0, 0, NULL);
diff --git a/net/can/raw.c b/net/can/raw.c
index 5b0e3e330d97..5d860e8dcc52 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -50,6 +50,7 @@
#include <linux/skbuff.h>
#include <linux/can.h>
#include <linux/can/core.h>
+#include <linux/can/skb.h>
#include <linux/can/raw.h>
#include <net/sock.h>
#include <net/net_namespace.h>
@@ -699,11 +700,14 @@ static int raw_sendmsg(struct kiocb *iocb, struct socket *sock,
if (!dev)
return -ENXIO;
- skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT,
- &err);
+ skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
+ msg->msg_flags & MSG_DONTWAIT, &err);
if (!skb)
goto put_dev;
+ skb_reserve(skb, sizeof(struct can_skb_priv));
+ ((struct can_skb_priv *)(skb->head))->ifindex = dev->ifindex;
+
err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
if (err < 0)
goto free_skb;
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-17 19:08:22 +0000