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Diffstat (limited to 'include/linux/can/skb.h')
-rw-r--r--include/linux/can/skb.h80
1 files changed, 80 insertions, 0 deletions
diff --git a/include/linux/can/skb.h b/include/linux/can/skb.h
index fc61cf4eff1c..685f34cfba20 100644
--- a/include/linux/can/skb.h
+++ b/include/linux/can/skb.h
@@ -16,6 +16,20 @@
#include <linux/can.h>
#include <net/sock.h>
+void can_flush_echo_skb(struct net_device *dev);
+int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
+ unsigned int idx, unsigned int frame_len);
+struct sk_buff *__can_get_echo_skb(struct net_device *dev, unsigned int idx,
+ u8 *len_ptr, unsigned int *frame_len_ptr);
+unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx,
+ unsigned int *frame_len_ptr);
+void can_free_echo_skb(struct net_device *dev, unsigned int idx);
+struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf);
+struct sk_buff *alloc_canfd_skb(struct net_device *dev,
+ struct canfd_frame **cfd);
+struct sk_buff *alloc_can_err_skb(struct net_device *dev,
+ struct can_frame **cf);
+
/*
* The struct can_skb_priv is used to transport additional information along
* with the stored struct can(fd)_frame that can not be contained in existing
@@ -29,11 +43,13 @@
* struct can_skb_priv - private additional data inside CAN sk_buffs
* @ifindex: ifindex of the first interface the CAN frame appeared on
* @skbcnt: atomic counter to have an unique id together with skb pointer
+ * @frame_len: length of CAN frame in data link layer
* @cf: align to the following CAN frame at skb->data
*/
struct can_skb_priv {
int ifindex;
int skbcnt;
+ unsigned int frame_len;
struct can_frame cf[];
};
@@ -74,4 +90,68 @@ static inline struct sk_buff *can_create_echo_skb(struct sk_buff *skb)
return nskb;
}
+/* Check for outgoing skbs that have not been created by the CAN subsystem */
+static inline bool can_skb_headroom_valid(struct net_device *dev,
+ struct sk_buff *skb)
+{
+ /* af_packet creates a headroom of HH_DATA_MOD bytes which is fine */
+ if (WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct can_skb_priv)))
+ return false;
+
+ /* af_packet does not apply CAN skb specific settings */
+ if (skb->ip_summed == CHECKSUM_NONE) {
+ /* init headroom */
+ can_skb_prv(skb)->ifindex = dev->ifindex;
+ can_skb_prv(skb)->skbcnt = 0;
+
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+ /* perform proper loopback on capable devices */
+ if (dev->flags & IFF_ECHO)
+ skb->pkt_type = PACKET_LOOPBACK;
+ else
+ skb->pkt_type = PACKET_HOST;
+
+ skb_reset_mac_header(skb);
+ skb_reset_network_header(skb);
+ skb_reset_transport_header(skb);
+ }
+
+ return true;
+}
+
+/* Drop a given socketbuffer if it does not contain a valid CAN frame. */
+static inline bool can_dropped_invalid_skb(struct net_device *dev,
+ struct sk_buff *skb)
+{
+ const struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
+
+ if (skb->protocol == htons(ETH_P_CAN)) {
+ if (unlikely(skb->len != CAN_MTU ||
+ cfd->len > CAN_MAX_DLEN))
+ goto inval_skb;
+ } else if (skb->protocol == htons(ETH_P_CANFD)) {
+ if (unlikely(skb->len != CANFD_MTU ||
+ cfd->len > CANFD_MAX_DLEN))
+ goto inval_skb;
+ } else
+ goto inval_skb;
+
+ if (!can_skb_headroom_valid(dev, skb))
+ goto inval_skb;
+
+ return false;
+
+inval_skb:
+ kfree_skb(skb);
+ dev->stats.tx_dropped++;
+ return true;
+}
+
+static inline bool can_is_canfd_skb(const struct sk_buff *skb)
+{
+ /* the CAN specific type of skb is identified by its data length */
+ return skb->len == CANFD_MTU;
+}
+
#endif /* !_CAN_SKB_H */