diff options
Diffstat (limited to 'include/linux/can/skb.h')
| -rw-r--r-- | include/linux/can/skb.h | 80 |
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 */ |