From 626332696d7506e8f844a564277bdba2dc78fcb5 Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Mon, 12 Sep 2022 19:07:25 +0200 Subject: [PATCH] can: raw: add CAN XL support Enable CAN_RAW sockets to read and write CAN XL frames analogue to the CAN FD extension (new CAN_RAW_XL_FRAMES sockopt). A CAN XL network interface is capable to handle Classical CAN, CAN FD and CAN XL frames. When CAN_RAW_XL_FRAMES is enabled, the CAN_RAW socket checks whether the addressed CAN network interface is capable to handle the provided CAN frame. In opposite to the fixed number of bytes for - CAN frames (CAN_MTU = sizeof(struct can_frame)) - CAN FD frames (CANFD_MTU = sizeof(struct can_frame)) the number of bytes when reading/writing CAN XL frames depends on the number of data bytes. For efficiency reasons the length of the struct canxl_frame is truncated to the needed size for read/write operations. This leads to a calculated size of CANXL_HDR_SIZE + canxl_frame::len which is enforced on write() operations and guaranteed on read() operations. NB: Valid length values are 1 .. 2048 (CANXL_MIN_DLEN .. CANXL_MAX_DLEN). Acked-by: Vincent Mailhol Signed-off-by: Oliver Hartkopp Link: https://lore.kernel.org/all/20220912170725.120748-8-socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde --- include/uapi/linux/can/raw.h | 1 + net/can/raw.c | 55 ++++++++++++++++++++++++++++++++++---------- 2 files changed, 44 insertions(+), 12 deletions(-) diff --git a/include/uapi/linux/can/raw.h b/include/uapi/linux/can/raw.h index 3386aa8..ff12f52 100644 --- a/include/uapi/linux/can/raw.h +++ b/include/uapi/linux/can/raw.h @@ -62,6 +62,7 @@ enum { CAN_RAW_RECV_OWN_MSGS, /* receive my own msgs (default:off) */ CAN_RAW_FD_FRAMES, /* allow CAN FD frames (default:off) */ CAN_RAW_JOIN_FILTERS, /* all filters must match to trigger */ + CAN_RAW_XL_FRAMES, /* allow CAN XL frames (default:off) */ }; #endif /* !_UAPI_CAN_RAW_H */ diff --git a/net/can/raw.c b/net/can/raw.c index e7dfa35..3eb7d3e 100644 --- a/net/can/raw.c +++ b/net/can/raw.c @@ -50,6 +50,7 @@ #include #include #include +#include /* for can_is_canxl_dev_mtu() */ #include #include #include @@ -87,6 +88,7 @@ struct raw_sock { int loopback; int recv_own_msgs; int fd_frames; + int xl_frames; int join_filters; int count; /* number of active filters */ struct can_filter dfilter; /* default/single filter */ @@ -129,8 +131,9 @@ static void raw_rcv(struct sk_buff *oskb, void *data) if (!ro->recv_own_msgs && oskb->sk == sk) return; - /* do not pass non-CAN2.0 frames to a legacy socket */ - if (!ro->fd_frames && oskb->len != CAN_MTU) + /* make sure to not pass oversized frames to the socket */ + if ((can_is_canfd_skb(oskb) && !ro->fd_frames && !ro->xl_frames) || + (can_is_canxl_skb(oskb) && !ro->xl_frames)) return; /* eliminate multiple filter matches for the same skb */ @@ -345,6 +348,7 @@ static int raw_init(struct sock *sk) ro->loopback = 1; ro->recv_own_msgs = 0; ro->fd_frames = 0; + ro->xl_frames = 0; ro->join_filters = 0; /* alloc_percpu provides zero'ed memory */ @@ -668,6 +672,15 @@ static int raw_setsockopt(struct socket *sock, int level, int optname, break; + case CAN_RAW_XL_FRAMES: + if (optlen != sizeof(ro->xl_frames)) + return -EINVAL; + + if (copy_from_sockptr(&ro->xl_frames, optval, optlen)) + return -EFAULT; + + break; + case CAN_RAW_JOIN_FILTERS: if (optlen != sizeof(ro->join_filters)) return -EINVAL; @@ -750,6 +763,12 @@ static int raw_getsockopt(struct socket *sock, int level, int optname, val = &ro->fd_frames; break; + case CAN_RAW_XL_FRAMES: + if (len > sizeof(int)) + len = sizeof(int); + val = &ro->xl_frames; + break; + case CAN_RAW_JOIN_FILTERS: if (len > sizeof(int)) len = sizeof(int); @@ -775,7 +794,11 @@ static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) struct sk_buff *skb; struct net_device *dev; int ifindex; - int err; + int err = -EINVAL; + + /* check for valid CAN frame sizes */ + if (size < CANXL_HDR_SIZE + CANXL_MIN_DLEN || size > CANXL_MTU) + return -EINVAL; if (msg->msg_name) { DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name); @@ -795,15 +818,6 @@ static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) if (!dev) return -ENXIO; - err = -EINVAL; - if (ro->fd_frames && dev->mtu == CANFD_MTU) { - if (unlikely(size != CANFD_MTU && size != CAN_MTU)) - goto put_dev; - } else { - if (unlikely(size != CAN_MTU)) - goto put_dev; - } - skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv), msg->msg_flags & MSG_DONTWAIT, &err); if (!skb) @@ -813,10 +827,27 @@ static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) can_skb_prv(skb)->ifindex = dev->ifindex; can_skb_prv(skb)->skbcnt = 0; + /* fill the skb before testing for valid CAN frames */ err = memcpy_from_msg(skb_put(skb, size), msg, size); if (err < 0) goto free_skb; + err = -EINVAL; + if (ro->xl_frames && can_is_canxl_dev_mtu(dev->mtu)) { + /* CAN XL, CAN FD and Classical CAN */ + if (!can_is_canxl_skb(skb) && !can_is_canfd_skb(skb) && + !can_is_can_skb(skb)) + goto free_skb; + } else if (ro->fd_frames && dev->mtu == CANFD_MTU) { + /* CAN FD and Classical CAN */ + if (!can_is_canfd_skb(skb) && !can_is_can_skb(skb)) + goto free_skb; + } else { + /* Classical CAN */ + if (!can_is_can_skb(skb)) + goto free_skb; + } + sockcm_init(&sockc, sk); if (msg->msg_controllen) { err = sock_cmsg_send(sk, msg, &sockc); -- 2.7.4