diff options
| -rw-r--r-- | Documentation/networking/index.rst | 1 | ||||
| -rw-r--r-- | Documentation/networking/j1939.rst | 422 | ||||
| -rw-r--r-- | MAINTAINERS | 10 | ||||
| -rw-r--r-- | include/linux/can/can-ml.h | 3 | ||||
| -rw-r--r-- | include/uapi/linux/can/j1939.h | 99 | ||||
| -rw-r--r-- | net/can/Kconfig | 2 | ||||
| -rw-r--r-- | net/can/Makefile | 2 | ||||
| -rw-r--r-- | net/can/j1939/Kconfig | 15 | ||||
| -rw-r--r-- | net/can/j1939/Makefile | 10 | ||||
| -rw-r--r-- | net/can/j1939/address-claim.c | 230 | ||||
| -rw-r--r-- | net/can/j1939/bus.c | 333 | ||||
| -rw-r--r-- | net/can/j1939/j1939-priv.h | 338 | ||||
| -rw-r--r-- | net/can/j1939/main.c | 403 | ||||
| -rw-r--r-- | net/can/j1939/socket.c | 1160 | ||||
| -rw-r--r-- | net/can/j1939/transport.c | 2027 |
15 files changed, 5055 insertions, 0 deletions
diff --git a/Documentation/networking/index.rst b/Documentation/networking/index.rst index 37eabc17894c..0481d0ffebed 100644 --- a/Documentation/networking/index.rst +++ b/Documentation/networking/index.rst @@ -17,6 +17,7 @@ Contents: devlink-trap devlink-trap-netdevsim ieee802154 + j1939 kapi z8530book msg_zerocopy diff --git a/Documentation/networking/j1939.rst b/Documentation/networking/j1939.rst new file mode 100644 index 000000000000..ce7e7a044e08 --- /dev/null +++ b/Documentation/networking/j1939.rst @@ -0,0 +1,422 @@ +.. SPDX-License-Identifier: (GPL-2.0 OR MIT) + +=================== +J1939 Documentation +=================== + +Overview / What Is J1939 +======================== + +SAE J1939 defines a higher layer protocol on CAN. It implements a more +sophisticated addressing scheme and extends the maximum packet size above 8 +bytes. Several derived specifications exist, which differ from the original +J1939 on the application level, like MilCAN A, NMEA2000 and especially +ISO-11783 (ISOBUS). This last one specifies the so-called ETP (Extended +Transport Protocol) which is has been included in this implementation. This +results in a maximum packet size of ((2 ^ 24) - 1) * 7 bytes == 111 MiB. + +Specifications used +------------------- + +* SAE J1939-21 : data link layer +* SAE J1939-81 : network management +* ISO 11783-6 : Virtual Terminal (Extended Transport Protocol) + +.. _j1939-motivation: + +Motivation +========== + +Given the fact there's something like SocketCAN with an API similar to BSD +sockets, we found some reasons to justify a kernel implementation for the +addressing and transport methods used by J1939. + +* **Addressing:** when a process on an ECU communicates via J1939, it should + not necessarily know its source address. Although at least one process per + ECU should know the source address. Other processes should be able to reuse + that address. This way, address parameters for different processes + cooperating for the same ECU, are not duplicated. This way of working is + closely related to the UNIX concept where programs do just one thing, and do + it well. + +* **Dynamic addressing:** Address Claiming in J1939 is time critical. + Furthermore data transport should be handled properly during the address + negotiation. Putting this functionality in the kernel eliminates it as a + requirement for _every_ user space process that communicates via J1939. This + results in a consistent J1939 bus with proper addressing. + +* **Transport:** both TP & ETP reuse some PGNs to relay big packets over them. + Different processes may thus use the same TP & ETP PGNs without actually + knowing it. The individual TP & ETP sessions _must_ be serialized + (synchronized) between different processes. The kernel solves this problem + properly and eliminates the serialization (synchronization) as a requirement + for _every_ user space process that communicates via J1939. + +J1939 defines some other features (relaying, gateway, fast packet transport, +...). In-kernel code for these would not contribute to protocol stability. +Therefore, these parts are left to user space. + +The J1939 sockets operate on CAN network devices (see SocketCAN). Any J1939 +user space library operating on CAN raw sockets will still operate properly. +Since such library does not communicate with the in-kernel implementation, care +must be taken that these two do not interfere. In practice, this means they +cannot share ECU addresses. A single ECU (or virtual ECU) address is used by +the library exclusively, or by the in-kernel system exclusively. + +J1939 concepts +============== + +PGN +--- + +The PGN (Parameter Group Number) is a number to identify a packet. The PGN +is composed as follows: +1 bit : Reserved Bit +1 bit : Data Page +8 bits : PF (PDU Format) +8 bits : PS (PDU Specific) + +In J1939-21 distinction is made between PDU1 format (where PF < 240) and PDU2 +format (where PF >= 240). Furthermore, when using PDU2 format, the PS-field +contains a so-called Group Extension, which is part of the PGN. When using PDU2 +format, the Group Extension is set in the PS-field. + +On the other hand, when using PDU1 format, the PS-field contains a so-called +Destination Address, which is _not_ part of the PGN. When communicating a PGN +from user space to kernel (or visa versa) and PDU2 format is used, the PS-field +of the PGN shall be set to zero. The Destination Address shall be set +elsewhere. + +Regarding PGN mapping to 29-bit CAN identifier, the Destination Address shall +be get/set from/to the appropriate bits of the identifier by the kernel. + + +Addressing +---------- + +Both static and dynamic addressing methods can be used. + +For static addresses, no extra checks are made by the kernel, and provided +addresses are considered right. This responsibility is for the OEM or system +integrator. + +For dynamic addressing, so-called Address Claiming, extra support is foreseen +in the kernel. In J1939 any ECU is known by it's 64-bit NAME. At the moment of +a successful address claim, the kernel keeps track of both NAME and source +address being claimed. This serves as a base for filter schemes. By default, +packets with a destination that is not locally, will be rejected. + +Mixed mode packets (from a static to a dynamic address or vice versa) are +allowed. The BSD sockets define separate API calls for getting/setting the +local & remote address and are applicable for J1939 sockets. + +Filtering +--------- + +J1939 defines white list filters per socket that a user can set in order to +receive a subset of the J1939 traffic. Filtering can be based on: + +* SA +* SOURCE_NAME +* PGN + +When multiple filters are in place for a single socket, and a packet comes in +that matches several of those filters, the packet is only received once for +that socket. + +How to Use J1939 +================ + +API Calls +--------- + +On CAN, you first need to open a socket for communicating over a CAN network. +To use J1939, #include <linux/can/j1939.h>. From there, <linux/can.h> will be +included too. To open a socket, use: + +.. code-block:: C + + s = socket(PF_CAN, SOCK_DGRAM, CAN_J1939); + +J1939 does use SOCK_DGRAM sockets. In the J1939 specification, connections are +mentioned in the context of transport protocol sessions. These still deliver +packets to the other end (using several CAN packets). SOCK_STREAM is not +supported. + +After the successful creation of the socket, you would normally use the bind(2) +and/or connect(2) system call to bind the socket to a CAN interface. After +binding and/or connecting the socket, you can read(2) and write(2) from/to the +socket or use send(2), sendto(2), sendmsg(2) and the recv*() counterpart +operations on the socket as usual. There are also J1939 specific socket options +described below. + +In order to send data, a bind(2) must have been successful. bind(2) assigns a +local address to a socket. + +Different from CAN is that the payload data is just the data that get send, +without it's header info. The header info is derived from the sockaddr supplied +to bind(2), connect(2), sendto(2) and recvfrom(2). A write(2) with size 4 will +result in a packet with 4 bytes. + +The sockaddr structure has extensions for use with J1939 as specified below: + +.. code-block:: C + + struct sockaddr_can { + sa_family_t can_family; + int can_ifindex; + union { + struct { + __u64 name; + /* pgn: + * 8 bit: PS in PDU2 case, else 0 + * 8 bit: PF + * 1 bit: DP + * 1 bit: reserved + */ + __u32 pgn; + __u8 addr; + } j1939; + } can_addr; + } + +can_family & can_ifindex serve the same purpose as for other SocketCAN sockets. + +can_addr.j1939.pgn specifies the PGN (max 0x3ffff). Individual bits are +specified above. + +can_addr.j1939.name contains the 64-bit J1939 NAME. + +can_addr.j1939.addr contains the address. + +The bind(2) system call assigns the local address, i.e. the source address when +sending packages. If a PGN during bind(2) is set, it's used as a RX filter. +I.e. only packets with a matching PGN are received. If an ADDR or NAME is set +it is used as a receive filter, too. It will match the destination NAME or ADDR +of the incoming packet. The NAME filter will work only if appropriate Address +Claiming for this name was done on the CAN bus and registered/cached by the +kernel. + +On the other hand connect(2) assigns the remote address, i.e. the destination +address. The PGN from connect(2) is used as the default PGN when sending +packets. If ADDR or NAME is set it will be used as the default destination ADDR +or NAME. Further a set ADDR or NAME during connect(2) is used as a receive +filter. It will match the source NAME or ADDR of the incoming packet. + +Both write(2) and send(2) will send a packet with local address from bind(2) and +the remote address from connect(2). Use sendto(2) to overwrite the destination +address. + +If can_addr.j1939.name is set (!= 0) the NAME is looked up by the kernel and +the corresponding ADDR is used. If can_addr.j1939.name is not set (== 0), +can_addr.j1939.addr is used. + +When creating a socket, reasonable defaults are set. Some options can be +modified with setsockopt(2) & getsockopt(2). + +RX path related options: + +- SO_J1939_FILTER - configure array of filters +- SO_J1939_PROMISC - disable filters set by bind(2) and connect(2) + +By default no broadcast packets can be send or received. To enable sending or +receiving broadcast packets use the socket option SO_BROADCAST: + +.. code-block:: C + + int value = 1; + setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &value, sizeof(value)); + +The following diagram illustrates the RX path: + +.. code:: + + +--------------------+ + | incoming packet | + +--------------------+ + | + V + +--------------------+ + | SO_J1939_PROMISC? | + +--------------------+ + | | + no | | yes + | | + .---------' `---------. + | | + +---------------------------+ | + | bind() + connect() + | | + | SOCK_BROADCAST filter | | + +---------------------------+ | + | | + |<---------------------' + V + +---------------------------+ + | SO_J1939_FILTER | + +---------------------------+ + | + V + +---------------------------+ + | socket recv() | + +---------------------------+ + +TX path related options: +SO_J1939_SEND_PRIO - change default send priority for the socket + +Message Flags during send() and Related System Calls +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +send(2), sendto(2) and sendmsg(2) take a 'flags' argument. Currently +supported flags are: + +* MSG_DONTWAIT, i.e. non-blocking operation. + +recvmsg(2) +^^^^^^^^^ + +In most cases recvmsg(2) is needed if you want to extract more information than +recvfrom(2) can provide. For example package priority and timestamp. The +Destination Address, name and packet priority (if applicable) are attached to +the msghdr in the recvmsg(2) call. They can be extracted using cmsg(3) macros, +with cmsg_level == SOL_J1939 && cmsg_type == SCM_J1939_DEST_ADDR, +SCM_J1939_DEST_NAME or SCM_J1939_PRIO. The returned data is a uint8_t for +priority and dst_addr, and uint64_t for dst_name. + +.. code-block:: C + + uint8_t priority, dst_addr; + uint64_t dst_name; + + for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) { + switch (cmsg->cmsg_level) { + case SOL_CAN_J1939: + if (cmsg->cmsg_type == SCM_J1939_DEST_ADDR) + dst_addr = *CMSG_DATA(cmsg); + else if (cmsg->cmsg_type == SCM_J1939_DEST_NAME) + memcpy(&dst_name, CMSG_DATA(cmsg), cmsg->cmsg_len - CMSG_LEN(0)); + else if (cmsg->cmsg_type == SCM_J1939_PRIO) + priority = *CMSG_DATA(cmsg); + break; + } + } + +Dynamic Addressing +------------------ + +Distinction has to be made between using the claimed address and doing an +address claim. To use an already claimed address, one has to fill in the +j1939.name member and provide it to bind(2). If the name had claimed an address +earlier, all further messages being sent will use that address. And the +j1939.addr member will be ignored. + +An exception on this is PGN 0x0ee00. This is the "Address Claim/Cannot Claim +Address" message and the kernel will use the j1939.addr member for that PGN if +necessary. + +To claim an address following code example can be used: + +.. code-block:: C + + struct sockaddr_can baddr = { + .can_family = AF_CAN, + .can_addr.j1939 = { + .name = name, + .addr = J1939_IDLE_ADDR, + .pgn = J1939_NO_PGN, /* to disable bind() rx filter for PGN */ + }, + .can_ifindex = if_nametoindex("can0"), + }; + + bind(sock, (struct sockaddr *)&baddr, sizeof(baddr)); + + /* for Address Claiming broadcast must be allowed */ + int value = 1; + setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &value, sizeof(value)); + + /* configured advanced RX filter with PGN needed for Address Claiming */ + const struct j1939_filter filt[] = { + { + .pgn = J1939_PGN_ADDRESS_CLAIMED, + .pgn_mask = J1939_PGN_PDU1_MAX, + }, { + .pgn = J1939_PGN_ADDRESS_REQUEST, + .pgn_mask = J1939_PGN_PDU1_MAX, + }, { + .pgn = J1939_PGN_ADDRESS_COMMANDED, + .pgn_mask = J1939_PGN_MAX, + }, + }; + + setsockopt(sock, SOL_CAN_J1939, SO_J1939_FILTER, &filt, sizeof(filt)); + + uint64_t dat = htole64(name); + const struct sockaddr_can saddr = { + .can_family = AF_CAN, + .can_addr.j1939 = { + .pgn = J1939_PGN_ADDRESS_CLAIMED, + .addr = J1939_NO_ADDR, + }, + }; + + /* Afterwards do a sendto(2) with data set to the NAME (Little Endian). If the + * NAME provided, does not match the j1939.name provided to bind(2), EPROTO + * will be returned. + */ + sendto(sock, dat, sizeof(dat), 0, (const struct sockaddr *)&saddr, sizeof(saddr)); + +If no-one else contests the address claim within 250ms after transmission, the +kernel marks the NAME-SA assignment as valid. The valid assignment will be kept +among other valid NAME-SA assignments. From that point, any socket bound to the +NAME can send packets. + +If another ECU claims the address, the kernel will mark the NAME-SA expired. +No socket bound to the NAME can send packets (other than address claims). To +claim another address, some socket bound to NAME, must bind(2) again, but with +only j1939.addr changed to the new SA, and must then send a valid address claim +packet. This restarts the state machine in the kernel (and any other +participant on the bus) for this NAME. + +can-utils also include the jacd tool, so it can be used as code example or as +default Address Claiming daemon. + +Send Examples +------------- + +Static Addressing +^^^^^^^^^^^^^^^^^ + +This example will send a PGN (0x12300) from SA 0x20 to DA 0x30. + +Bind: + +.. code-block:: C + + struct sockaddr_can baddr = { + .can_family = AF_CAN, + .can_addr.j1939 = { + .name = J1939_NO_NAME, + .addr = 0x20, + .pgn = J1939_NO_PGN, + }, + .can_ifindex = if_nametoindex("can0"), + }; + + bind(sock, (struct sockaddr *)&baddr, sizeof(baddr)); + +Now, the socket 'sock' is bound to the SA 0x20. Since no connect(2) was called, +at this point we can use only sendto(2) or sendmsg(2). + +Send: + +.. code-block:: C + + const struct sockaddr_can saddr = { + .can_family = AF_CAN, + .can_addr.j1939 = { + .name = J1939_NO_NAME; + .pgn = 0x30, + .addr = 0x12300, + }, + }; + + sendto(sock, dat, sizeof(dat), 0, (const struct sockaddr *)&saddr, sizeof(saddr)); diff --git a/MAINTAINERS b/MAINTAINERS index a081c477d1d1..844f416437c4 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3669,6 +3669,16 @@ F: include/uapi/linux/can/bcm.h F: include/uapi/linux/can/raw.h F: include/uapi/linux/can/gw.h +CAN-J1939 NETWORK LAYER +M: Robin van der Gracht <robin@protonic.nl> +M: Oleksij Rempel <o.rempel@pengutronix.de> +R: Pengutronix Kernel Team <kernel@pengutronix.de> +L: linux-can@vger.kernel.org +S: Maintained +F: Documentation/networking/j1939.txt +F: net/can/j1939/ +F: include/uapi/linux/can/j1939.h + CAPABILITIES M: Serge Hallyn <serge@hallyn.com> L: linux-security-module@vger.kernel.org diff --git a/include/linux/can/can-ml.h b/include/linux/can/can-ml.h index 79ccf6bfa232..2f5d731ae251 100644 --- a/include/linux/can/can-ml.h +++ b/include/linux/can/can-ml.h @@ -60,6 +60,9 @@ struct can_dev_rcv_lists { struct can_ml_priv { struct can_dev_rcv_lists dev_rcv_lists; +#ifdef CAN_J1939 + struct j1939_priv *j1939_priv; +#endif }; #endif /* CAN_ML_H */ diff --git a/include/uapi/linux/can/j1939.h b/include/uapi/linux/can/j1939.h new file mode 100644 index 000000000000..c32325342d30 --- /dev/null +++ b/include/uapi/linux/can/j1939.h @@ -0,0 +1,99 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* + * j1939.h + * + * Copyright (c) 2010-2011 EIA Electronics + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#ifndef _UAPI_CAN_J1939_H_ +#define _UAPI_CAN_J1939_H_ + +#include <linux/types.h> +#include <linux/socket.h> +#include <linux/can.h> + +#define J1939_MAX_UNICAST_ADDR 0xfd +#define J1939_IDLE_ADDR 0xfe +#define J1939_NO_ADDR 0xff /* == broadcast or no addr */ +#define J1939_NO_NAME 0 +#define J1939_PGN_REQUEST 0x0ea00 /* Request PG */ +#define J1939_PGN_ADDRESS_CLAIMED 0x0ee00 /* Address Claimed */ +#define J1939_PGN_ADDRESS_COMMANDED 0x0fed8 /* Commanded Address */ +#define J1939_PGN_PDU1_MAX 0x3ff00 +#define J1939_PGN_MAX 0x3ffff +#define J1939_NO_PGN 0x40000 + +/* J1939 Parameter Group Number + * + * bit 0-7 : PDU Specific (PS) + * bit 8-15 : PDU Format (PF) + * bit 16 : Data Page (DP) + * bit 17 : Reserved (R) + * bit 19-31 : set to zero + */ +typedef __u32 pgn_t; + +/* J1939 Priority + * + * bit 0-2 : Priority (P) + * bit 3-7 : set to zero + */ +typedef __u8 priority_t; + +/* J1939 NAME + * + * bit 0-20 : Identity Number + * bit 21-31 : Manufacturer Code + * bit 32-34 : ECU Instance + * bit 35-39 : Function Instance + * bit 40-47 : Function + * bit 48 : Reserved + * bit 49-55 : Vehicle System + * bit 56-59 : Vehicle System Instance + * bit 60-62 : Industry Group + * bit 63 : Arbitrary Address Capable + */ +typedef __u64 name_t; + +/* J1939 socket options */ +#define SOL_CAN_J1939 (SOL_CAN_BASE + CAN_J1939) +enum { + SO_J1939_FILTER = 1, /* set filters */ + SO_J1939_PROMISC = 2, /* set/clr promiscuous mode */ + SO_J1939_SEND_PRIO = 3, + SO_J1939_ERRQUEUE = 4, +}; + +enum { + SCM_J1939_DEST_ADDR = 1, + SCM_J1939_DEST_NAME = 2, + SCM_J1939_PRIO = 3, + SCM_J1939_ERRQUEUE = 4, +}; + +enum { + J1939_NLA_PAD, + J1939_NLA_BYTES_ACKED, +}; + +enum { + J1939_EE_INFO_NONE, + J1939_EE_INFO_TX_ABORT, +}; + +struct j1939_filter { + name_t name; + name_t name_mask; + pgn_t pgn; + pgn_t pgn_mask; + __u8 addr; + __u8 addr_mask; +}; + +#define J1939_FILTER_MAX 512 /* maximum number of j1939_filter set via setsockopt() */ + +#endif /* !_UAPI_CAN_J1939_H_ */ diff --git a/net/can/Kconfig b/net/can/Kconfig index d4319aa3e1b1..d77042752457 100644 --- a/net/can/Kconfig +++ b/net/can/Kconfig @@ -53,6 +53,8 @@ config CAN_GW They can be modified with AND/OR/XOR/SET operations as configured by the netlink configuration interface known e.g. from iptables. +source "net/can/j1939/Kconfig" + source "drivers/net/can/Kconfig" endif diff --git a/net/can/Makefile b/net/can/Makefile index 1242bbbfe57f..08bd217fc051 100644 --- a/net/can/Makefile +++ b/net/can/Makefile @@ -15,3 +15,5 @@ can-bcm-y := bcm.o obj-$(CONFIG_CAN_GW) += can-gw.o can-gw-y := gw.o + +obj-$(CONFIG_CAN_J1939) += j1939/ diff --git a/net/can/j1939/Kconfig b/net/can/j1939/Kconfig new file mode 100644 index 000000000000..2998298b71ec --- /dev/null +++ b/net/can/j1939/Kconfig @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# SAE J1939 network layer core configuration +# + +config CAN_J1939 + tristate "SAE J1939" + depends on CAN + help + SAE J1939 + Say Y to have in-kernel support for j1939 socket type. This + allows communication according to SAE j1939. + The relevant parts in kernel are + SAE j1939-21 (datalink & transport protocol) + & SAE j1939-81 (network management). diff --git a/net/can/j1939/Makefile b/net/can/j1939/Makefile new file mode 100644 index 000000000000..19181bdae173 --- /dev/null +++ b/net/can/j1939/Makefile @@ -0,0 +1,10 @@ +# SPDX-License-Identifier: GPL-2.0 + +obj-$(CONFIG_CAN_J1939) += can-j1939.o + +can-j1939-objs := \ + address-claim.o \ + bus.o \ + main.o \ + socket.o \ + transport.o diff --git a/net/can/j1939/address-claim.c b/net/can/j1939/address-claim.c new file mode 100644 index 000000000000..f33c47327927 --- /dev/null +++ b/net/can/j1939/address-claim.c @@ -0,0 +1,230 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2010-2011 EIA Electronics, +// Kurt Van Dijck <kurt.van.dijck@eia.be> +// Copyright (c) 2010-2011 EIA Electronics, +// Pieter Beyens <pieter.beyens@eia.be> +// Copyright (c) 2017-2019 Pengutronix, +// Marc Kleine-Budde <kernel@pengutronix.de> +// Copyright (c) 2017-2019 Pengutronix, +// Oleksij Rempel <kernel@pengutronix.de> + +/* J1939 Address Claiming. + * Address Claiming in the kernel + * - keeps track of the AC states of ECU's, + * - resolves NAME<=>SA taking into account the AC states of ECU's. + * + * All Address Claim msgs (including host-originated msg) are processed + * at the receive path (a sent msg is always received again via CAN echo). + * As such, the processing of AC msgs is done in the order on which msgs + * are sent on the bus. + * + * This module doesn't send msgs itself (e.g. replies on Address Claims), + * this is the responsibility of a user space application or daemon. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/netdevice.h> +#include <linux/skbuff.h> + +#include "j1939-priv.h" + +static inline name_t j1939_skb_to_name(const struct sk_buff *skb) +{ + return le64_to_cpup((__le64 *)skb->data); +} + +static inline bool j1939_ac_msg_is_request(struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + int req_pgn; + + if (skb->len < 3 || skcb->addr.pgn != J1939_PGN_REQUEST) + return false; + + req_pgn = skb->data[0] | (skb->data[1] << 8) | (skb->data[2] << 16); + + return req_pgn == J1939_PGN_ADDRESS_CLAIMED; +} + +static int j1939_ac_verify_outgoing(struct j1939_priv *priv, + struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + + if (skb->len != 8) { + netdev_notice(priv->ndev, "tx address claim with dlc %i\n", + skb->len); + return -EPROTO; + } + + if (skcb->addr.src_name != j1939_skb_to_name(skb)) { + netdev_notice(priv->ndev, "tx address claim with different name\n"); + return -EPROTO; + } + + if (skcb->addr.sa == J1939_NO_ADDR) { + netdev_notice(priv->ndev, "tx address claim with broadcast sa\n"); + return -EPROTO; + } + + /* ac must always be a broadcast */ + if (skcb->addr.dst_name || skcb->addr.da != J1939_NO_ADDR) { + netdev_notice(priv->ndev, "tx address claim with dest, not broadcast\n"); + return -EPROTO; + } + return 0; +} + +int j1939_ac_fixup(struct j1939_priv *priv, struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + int ret; + u8 addr; + + /* network mgmt: address claiming msgs */ + if (skcb->addr.pgn == J1939_PGN_ADDRESS_CLAIMED) { + struct j1939_ecu *ecu; + + ret = j1939_ac_verify_outgoing(priv, skb); + /* return both when failure & when successful */ + if (ret < 0) + return ret; + ecu = j1939_ecu_get_by_name(priv, skcb->addr.src_name); + if (!ecu) + return -ENODEV; + + if (ecu->addr != skcb->addr.sa) + /* hold further traffic for ecu, remove from parent */ + j1939_ecu_unmap(ecu); + j1939_ecu_put(ecu); + } else if (skcb->addr.src_name) { + /* assign source address */ + addr = j1939_name_to_addr(priv, skcb->addr.src_name); + if (!j1939_address_is_unicast(addr) && + !j1939_ac_msg_is_request(skb)) { + netdev_notice(priv->ndev, "tx drop: invalid sa for name 0x%016llx\n", + skcb->addr.src_name); + return -EADDRNOTAVAIL; + } + skcb->addr.sa = addr; + } + + /* assign destination address */ + if (skcb->addr.dst_name) { + addr = j1939_name_to_addr(priv, skcb->addr.dst_name); + if (!j1939_address_is_unicast(addr)) { + netdev_notice(priv->ndev, "tx drop: invalid da for name 0x%016llx\n", + skcb->addr.dst_name); + return -EADDRNOTAVAIL; + } + skcb->addr.da = addr; + } + return 0; +} + +static void j1939_ac_process(struct j1939_priv *priv, struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_ecu *ecu, *prev; + name_t name; + + if (skb->len != 8) { + netdev_notice(priv->ndev, "rx address claim with wrong dlc %i\n", + skb->len); + return; + } + + name = j1939_skb_to_name(skb); + skcb->addr.src_name = name; + if (!name) { + netdev_notice(priv->ndev, "rx address claim without name\n"); + return; + } + + if (!j1939_address_is_valid(skcb->addr.sa)) { + netdev_notice(priv->ndev, "rx address claim with broadcast sa\n"); + return; + } + + write_lock_bh(&priv->lock); + + /* Few words on the ECU ref counting: + * + * First we get an ECU handle, either with + * j1939_ecu_get_by_name_locked() (increments the ref counter) + * or j1939_ecu_create_locked() (initializes an ECU object + * with a ref counter of 1). + * + * j1939_ecu_unmap_locked() will decrement the ref counter, + * but only if the ECU was mapped before. So "ecu" still + * belongs to us. + * + * j1939_ecu_timer_start() will increment the ref counter + * before it starts the timer, so we can put the ecu when + * leaving this function. + */ + ecu = j1939_ecu_get_by_name_locked(priv, name); + if (!ecu && j1939_address_is_unicast(skcb->addr.sa)) + ecu = j1939_ecu_create_locked(priv, name); + + if (IS_ERR_OR_NULL(ecu)) + goto out_unlock_bh; + + /* cancel pending (previous) address claim */ + j1939_ecu_timer_cancel(ecu); + + if (j1939_address_is_idle(skcb->addr.sa)) { + j1939_ecu_unmap_locked(ecu); + goto out_ecu_put; + } + + /* save new addr */ + if (ecu->addr != skcb->addr.sa) + j1939_ecu_unmap_locked(ecu); + ecu->addr = skcb->addr.sa; + + prev = j1939_ecu_get_by_addr_locked(priv, skcb->addr.sa); + if (prev) { + if (ecu->name > prev->name) { + j1939_ecu_unmap_locked(ecu); + j1939_ecu_put(prev); + goto out_ecu_put; + } else { + /* kick prev if less or equal */ + j1939_ecu_unmap_locked(prev); + j1939_ecu_put(prev); + } + } + + j1939_ecu_timer_start(ecu); + out_ecu_put: + j1939_ecu_put(ecu); + out_unlock_bh: + write_unlock_bh(&priv->lock); +} + +void j1939_ac_recv(struct j1939_priv *priv, struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_ecu *ecu; + + /* network mgmt */ + if (skcb->addr.pgn == J1939_PGN_ADDRESS_CLAIMED) { + j1939_ac_process(priv, skb); + } else if (j1939_address_is_unicast(skcb->addr.sa)) { + /* assign source name */ + ecu = j1939_ecu_get_by_addr(priv, skcb->addr.sa); + if (ecu) { + skcb->addr.src_name = ecu->name; + j1939_ecu_put(ecu); + } + } + + /* assign destination name */ + ecu = j1939_ecu_get_by_addr(priv, skcb->addr.da); + if (ecu) { + skcb->addr.dst_name = ecu->name; + j1939_ecu_put(ecu); + } +} diff --git a/net/can/j1939/bus.c b/net/can/j1939/bus.c new file mode 100644 index 000000000000..486687901602 --- /dev/null +++ b/net/can/j1939/bus.c @@ -0,0 +1,333 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2010-2011 EIA Electronics, +// Kurt Van Dijck <kurt.van.dijck@eia.be> +// Copyright (c) 2017-2019 Pengutronix, +// Marc Kleine-Budde <kernel@pengutronix.de> +// Copyright (c) 2017-2019 Pengutronix, +// Oleksij Rempel <kernel@pengutronix.de> + +/* bus for j1939 remote devices + * Since rtnetlink, no real bus is used. + */ + +#include <net/sock.h> + +#include "j1939-priv.h" + +static void __j1939_ecu_release(struct kref *kref) +{ + struct j1939_ecu *ecu = container_of(kref, struct j1939_ecu, kref); + struct j1939_priv *priv = ecu->priv; + + list_del(&ecu->list); + kfree(ecu); + j1939_priv_put(priv); +} + +void j1939_ecu_put(struct j1939_ecu *ecu) +{ + kref_put(&ecu->kref, __j1939_ecu_release); +} + +static void j1939_ecu_get(struct j1939_ecu *ecu) +{ + kref_get(&ecu->kref); +} + +static bool j1939_ecu_is_mapped_locked(struct j1939_ecu *ecu) +{ + struct j1939_priv *priv = ecu->priv; + + lockdep_assert_held(&priv->lock); + + return j1939_ecu_find_by_addr_locked(priv, ecu->addr) == ecu; +} + +/* ECU device interface */ +/* map ECU to a bus address space */ +static void j1939_ecu_map_locked(struct j1939_ecu *ecu) +{ + struct j1939_priv *priv = ecu->priv; + struct j1939_addr_ent *ent; + + lockdep_assert_held(&priv->lock); + + if (!j1939_address_is_unicast(ecu->addr)) + return; + + ent = &priv->ents[ecu->addr]; + + if (ent->ecu) { + netdev_warn(priv->ndev, "Trying to map already mapped ECU, addr: 0x%02x, name: 0x%016llx. Skip it.\n", + ecu->addr, ecu->name); + return; + } + + j1939_ecu_get(ecu); + ent->ecu = ecu; + ent->nusers += ecu->nusers; +} + +/* unmap ECU from a bus address space */ +void j1939_ecu_unmap_locked(struct j1939_ecu *ecu) +{ + struct j1939_priv *priv = ecu->priv; + struct j1939_addr_ent *ent; + + lockdep_assert_held(&priv->lock); + + if (!j1939_address_is_unicast(ecu->addr)) + return; + + if (!j1939_ecu_is_mapped_locked(ecu)) + return; + + ent = &priv->ents[ecu->addr]; + ent->ecu = NULL; + ent->nusers -= ecu->nusers; + j1939_ecu_put(ecu); +} + +void j1939_ecu_unmap(struct j1939_ecu *ecu) +{ + write_lock_bh(&ecu->priv->lock); + j1939_ecu_unmap_locked(ecu); + write_unlock_bh(&ecu->priv->lock); +} + +void j1939_ecu_unmap_all(struct j1939_priv *priv) +{ + int i; + + write_lock_bh(&priv->lock); + for (i = 0; i < ARRAY_SIZE(priv->ents); i++) + if (priv->ents[i].ecu) + j1939_ecu_unmap_locked(priv->ents[i].ecu); + write_unlock_bh(&priv->lock); +} + +void j1939_ecu_timer_start(struct j1939_ecu *ecu) +{ + /* The ECU is held here and released in the + * j1939_ecu_timer_handler() or j1939_ecu_timer_cancel(). + */ + j1939_ecu_get(ecu); + + /* Schedule timer in 250 msec to commit address change. */ + hrtimer_start(&ecu->ac_timer, ms_to_ktime(250), + HRTIMER_MODE_REL_SOFT); +} + +void j1939_ecu_timer_cancel(struct j1939_ecu *ecu) +{ + if (hrtimer_cancel(&ecu->ac_timer)) + j1939_ecu_put(ecu); +} + +static enum hrtimer_restart j1939_ecu_timer_handler(struct hrtimer *hrtimer) +{ + struct j1939_ecu *ecu = + container_of(hrtimer, struct j1939_ecu, ac_timer); + struct j1939_priv *priv = ecu->priv; + + write_lock_bh(&priv->lock); + /* TODO: can we test if ecu->addr is unicast before starting + * the timer? + */ + j1939_ecu_map_locked(ecu); + + /* The corresponding j1939_ecu_get() is in + * j1939_ecu_timer_start(). + */ + j1939_ecu_put(ecu); + write_unlock_bh(&priv->lock); + + return HRTIMER_NORESTART; +} + +struct j1939_ecu *j1939_ecu_create_locked(struct j1939_priv *priv, name_t name) +{ + struct j1939_ecu *ecu; + + lockdep_assert_held(&priv->lock); + + ecu = kzalloc(sizeof(*ecu), gfp_any()); + if (!ecu) + return ERR_PTR(-ENOMEM); + kref_init(&ecu->kref); + ecu->addr = J1939_IDLE_ADDR; + ecu->name = name; + + hrtimer_init(&ecu->ac_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT); + ecu->ac_timer.function = j1939_ecu_timer_handler; + INIT_LIST_HEAD(&ecu->list); + + j1939_priv_get(priv); + ecu->priv = priv; + list_add_tail(&ecu->list, &priv->ecus); + + return ecu; +} + +struct j1939_ecu *j1939_ecu_find_by_addr_locked(struct j1939_priv *priv, + u8 addr) +{ + lockdep_assert_held(&priv->lock); + + return priv->ents[addr].ecu; +} + +struct j1939_ecu *j1939_ecu_get_by_addr_locked(struct j1939_priv *priv, u8 addr) +{ + struct j1939_ecu *ecu; + + lockdep_assert_held(&priv->lock); + + if (!j1939_address_is_unicast(addr)) + return NULL; + + ecu = j1939_ecu_find_by_addr_locked(priv, addr); + if (ecu) + j1939_ecu_get(ecu); + + return ecu; +} + +struct j1939_ecu *j1939_ecu_get_by_addr(struct j1939_priv *priv, u8 addr) +{ + struct j1939_ecu *ecu; + + read_lock_bh(&priv->lock); + ecu = j1939_ecu_get_by_addr_locked(priv, addr); + read_unlock_bh(&priv->lock); + + return ecu; +} + +/* get pointer to ecu without increasing ref counter */ +static struct j1939_ecu *j1939_ecu_find_by_name_locked(struct j1939_priv *priv, + name_t name) +{ + struct j1939_ecu *ecu; + + lockdep_assert_held(&priv->lock); + + list_for_each_entry(ecu, &priv->ecus, list) { + if (ecu->name == name) + return ecu; + } + + return NULL; +} + +struct j1939_ecu *j1939_ecu_get_by_name_locked(struct j1939_priv *priv, + name_t name) +{ + struct j1939_ecu *ecu; + + lockdep_assert_held(&priv->lock); + + if (!name) + return NULL; + + ecu = j1939_ecu_find_by_name_locked(priv, name); + if (ecu) + j1939_ecu_get(ecu); + + return ecu; +} + +struct j1939_ecu *j1939_ecu_get_by_name(struct j1939_priv *priv, name_t name) +{ + struct j1939_ecu *ecu; + + read_lock_bh(&priv->lock); + ecu = j1939_ecu_get_by_name_locked(priv, name); + read_unlock_bh(&priv->lock); + + return ecu; +} + +u8 j1939_name_to_addr(struct j1939_priv *priv, name_t name) +{ + struct j1939_ecu *ecu; + int addr = J1939_IDLE_ADDR; + + if (!name) + return J1939_NO_ADDR; + + read_lock_bh(&priv->lock); + ecu = j1939_ecu_find_by_name_locked(priv, name); + if (ecu && j1939_ecu_is_mapped_locked(ecu)) + /* ecu's SA is registered */ + addr = ecu->addr; + + read_unlock_bh(&priv->lock); + + return addr; +} + +/* TX addr/name accounting + * Transport protocol needs to know if a SA is local or not + * These functions originate from userspace manipulating sockets, + * so locking is straigforward + */ + +int j1939_local_ecu_get(struct j1939_priv *priv, name_t name, u8 sa) +{ + struct j1939_ecu *ecu; + int err = 0; + + write_lock_bh(&priv->lock); + + if (j1939_address_is_unicast(sa)) + priv->ents[sa].nusers++; + + if (!name) + goto done; + + ecu = j1939_ecu_get_by_name_locked(priv, name); + if (!ecu) + ecu = j1939_ecu_create_locked(priv, name); + err = PTR_ERR_OR_ZERO(ecu); + if (err) + goto done; + + ecu->nusers++; + /* TODO: do we care if ecu->addr != sa? */ + if (j1939_ecu_is_mapped_locked(ecu)) + /* ecu's sa is active already */ + priv->ents[ecu->addr].nusers++; + + done: + write_unlock_bh(&priv->lock); + + return err; +} + +void j1939_local_ecu_put(struct j1939_priv *priv, name_t name, u8 sa) +{ + struct j1939_ecu *ecu; + + write_lock_bh(&priv->lock); + + if (j1939_address_is_unicast(sa)) + priv->ents[sa].nusers--; + + if (!name) + goto done; + + ecu = j1939_ecu_find_by_name_locked(priv, name); + if (WARN_ON_ONCE(!ecu)) + goto done; + + ecu->nusers--; + /* TODO: do we care if ecu->addr != sa? */ + if (j1939_ecu_is_mapped_locked(ecu)) + /* ecu's sa is active already */ + priv->ents[ecu->addr].nusers--; + j1939_ecu_put(ecu); + + done: + write_unlock_bh(&priv->lock); +} diff --git a/net/can/j1939/j1939-priv.h b/net/can/j1939/j1939-priv.h new file mode 100644 index 000000000000..12369b604ce9 --- /dev/null +++ b/net/can/j1939/j1939-priv.h @@ -0,0 +1,338 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +// Copyright (c) 2010-2011 EIA Electronics, +// Kurt Van Dijck <kurt.van.dijck@eia.be> +// Copyright (c) 2017-2019 Pengutronix, +// Marc Kleine-Budde <kernel@pengutronix.de> +// Copyright (c) 2017-2019 Pengutronix, +// Oleksij Rempel <kernel@pengutronix.de> + +#ifndef _J1939_PRIV_H_ +#define _J1939_PRIV_H_ + +#include <linux/can/j1939.h> +#include <net/sock.h> + +/* Timeout to receive the abort signal over loop back. In case CAN + * bus is open, the timeout should be triggered. + */ +#define J1939_XTP_ABORT_TIMEOUT_MS 500 +#define J1939_SIMPLE_ECHO_TIMEOUT_MS (10 * 1000) + +struct j1939_session; +enum j1939_sk_errqueue_type { + J1939_ERRQUEUE_ACK, + J1939_ERRQUEUE_SCHED, + J1939_ERRQUEUE_ABORT, +}; + +/* j1939 devices */ +struct j1939_ecu { + struct list_head list; + name_t name; + u8 addr; + + /* indicates that this ecu successfully claimed @sa as its address */ + struct hrtimer ac_timer; + struct kref kref; + struct j1939_priv *priv; + + /* count users, to help transport protocol decide for interaction */ + int nusers; +}; + +struct j1939_priv { + struct list_head ecus; + /* local list entry in priv + * These allow irq (& softirq) context lookups on j1939 devices + * This approach (separate lists) is done as the other 2 alternatives + * are not easier or even wrong + * 1) using the pure kobject methods involves mutexes, which are not + * allowed in irq context. + * 2) duplicating data structures would require a lot of synchronization + * code + * usage: + */ + + /* segments need a lock to protect the above list */ + rwlock_t lock; + + struct net_device *ndev; + + /* list of 256 ecu ptrs, that cache the claimed addresses. + * also protected by the above lock + */ + struct j1939_addr_ent { + struct j1939_ecu *ecu; + /* count users, to help transport protocol */ + int nusers; + } ents[256]; + + struct kref kref; + + /* List of active sessions to prevent start of conflicting + * one. + * + * Do not start two sessions of same type, addresses and + * direction. + */ + struct list_head active_session_list; + + /* protects active_session_list */ + spinlock_t active_session_list_lock; + + unsigned int tp_max_packet_size; + + /* lock for j1939_socks list */ + spinlock_t j1939_socks_lock; + struct list_head j1939_socks; + + struct kref rx_kref; +}; + +void j1939_ecu_put(struct j1939_ecu *ecu); + +/* keep the cache of what is local */ +int j1939_local_ecu_get(struct j1939_priv *priv, name_t name, u8 sa); +void j1939_local_ecu_put(struct j1939_priv *priv, name_t name, u8 sa); + +static inline bool j1939_address_is_unicast(u8 addr) +{ + return addr <= J1939_MAX_UNICAST_ADDR; +} + +static inline bool j1939_address_is_idle(u8 addr) +{ + return addr == J1939_IDLE_ADDR; +} + +static inline bool j1939_address_is_valid(u8 addr) +{ + return addr != J1939_NO_ADDR; +} + +static inline bool j1939_pgn_is_pdu1(pgn_t pgn) +{ + /* ignore dp & res bits for this */ + return (pgn & 0xff00) < 0xf000; +} + +/* utility to correctly unmap an ECU */ +void j1939_ecu_unmap_locked(struct j1939_ecu *ecu); +void j1939_ecu_unmap(struct j1939_ecu *ecu); + +u8 j1939_name_to_addr(struct j1939_priv *priv, name_t name); +struct j1939_ecu *j1939_ecu_find_by_addr_locked(struct j1939_priv *priv, + u8 addr); +struct j1939_ecu *j1939_ecu_get_by_addr(struct j1939_priv *priv, u8 addr); +struct j1939_ecu *j1939_ecu_get_by_addr_locked(struct j1939_priv *priv, + u8 addr); +struct j1939_ecu *j1939_ecu_get_by_name(struct j1939_priv *priv, name_t name); +struct j1939_ecu *j1939_ecu_get_by_name_locked(struct j1939_priv *priv, + name_t name); + +enum j1939_transfer_type { + J1939_TP, + J1939_ETP, + J1939_SIMPLE, +}; + +struct j1939_addr { + name_t src_name; + name_t dst_name; + pgn_t pgn; + + u8 sa; + u8 da; + + u8 type; +}; + +/* control buffer of the sk_buff */ +struct j1939_sk_buff_cb { + /* Offset in bytes within one ETP session */ + u32 offset; + + /* for tx, MSG_SYN will be used to sync on sockets */ + u32 msg_flags; + u32 tskey; + + struct j1939_addr addr; + + /* Flags for quick lookups during skb processing. + * These are set in the receive path only. + */ +#define J1939_ECU_LOCAL_SRC BIT(0) +#define J1939_ECU_LOCAL_DST BIT(1) + u8 flags; + + priority_t priority; +}; + +static inline +struct j1939_sk_buff_cb *j1939_skb_to_cb(const struct sk_buff *skb) +{ + BUILD_BUG_ON(sizeof(struct j1939_sk_buff_cb) > sizeof(skb->cb)); + + return (struct j1939_sk_buff_cb *)skb->cb; +} + +int j1939_send_one(struct j1939_priv *priv, struct sk_buff *skb); +void j1939_sk_recv(struct j1939_priv *priv, struct sk_buff *skb); +bool j1939_sk_recv_match(struct j1939_priv *priv, + struct j1939_sk_buff_cb *skcb); +void j1939_sk_send_loop_abort(struct sock *sk, int err); +void j1939_sk_errqueue(struct j1939_session *session, + enum j1939_sk_errqueue_type type); +void j1939_sk_queue_activate_next(struct j1939_session *session); + +/* stack entries */ +struct j1939_session *j1939_tp_send(struct j1939_priv *priv, + struct sk_buff *skb, size_t size); +int j1939_tp_recv(struct j1939_priv *priv, struct sk_buff *skb); +int j1939_ac_fixup(struct j1939_priv *priv, struct sk_buff *skb); +void j1939_ac_recv(struct j1939_priv *priv, struct sk_buff *skb); +void j1939_simple_recv(struct j1939_priv *priv, struct sk_buff *skb); + +/* network management */ +struct j1939_ecu *j1939_ecu_create_locked(struct j1939_priv *priv, name_t name); + +void j1939_ecu_timer_start(struct j1939_ecu *ecu); +void j1939_ecu_timer_cancel(struct j1939_ecu *ecu); +void j1939_ecu_unmap_all(struct j1939_priv *priv); + +struct j1939_priv *j1939_netdev_start(struct net_device *ndev); +void j1939_netdev_stop(struct j1939_priv *priv); + +void j1939_priv_put(struct j1939_priv *priv); +void j1939_priv_get(struct j1939_priv *priv); + +/* notify/alert all j1939 sockets bound to ifindex */ +void j1939_sk_netdev_event_netdown(struct j1939_priv *priv); +int j1939_cancel_active_session(struct j1939_priv *priv, struct sock *sk); +void j1939_tp_init(struct j1939_priv *priv); + +/* decrement pending skb for a j1939 socket */ +void j1939_sock_pending_del(struct sock *sk); + +enum j1939_session_state { + J1939_SESSION_NEW, + J1939_SESSION_ACTIVE, + /* waiting for abort signal on the bus */ + J1939_SESSION_WAITING_ABORT, + J1939_SESSION_ACTIVE_MAX, + J1939_SESSION_DONE, +}; + +struct j1939_session { + struct j1939_priv *priv; + struct list_head active_session_list_entry; + struct list_head sk_session_queue_entry; + struct kref kref; + struct sock *sk; + + /* ifindex, src, dst, pgn define the session block + * the are _never_ modified after insertion in the list + * this decreases locking problems a _lot_ + */ + struct j1939_sk_buff_cb skcb; + struct sk_buff_head skb_queue; + + /* all tx related stuff (last_txcmd, pkt.tx) + * is protected (modified only) with the txtimer hrtimer + * 'total' & 'block' are never changed, + * last_cmd, last & block are protected by ->lock + * this means that the tx may run after cts is received that should + * have stopped tx, but this time discrepancy is never avoided anyhow + */ + u8 last_cmd, last_txcmd; + bool transmission; + bool extd; + /* Total message size, number of bytes */ + unsigned int total_message_size; + /* Total number of bytes queue from socket to the session */ + unsigned int total_queued_size; + unsigned int tx_retry; + + int err; + u32 tskey; + enum j1939_session_state state; + + /* Packets counters for a (extended) transfer session. The packet is + * maximal of 7 bytes. + */ + struct { + /* total - total number of packets for this session */ + unsigned int total; + /* last - last packet of a transfer block after which + * responder should send ETP.CM_CTS and originator + * ETP.CM_DPO + */ + unsigned int last; + /* tx - number of packets send by originator node. + * this counter can be set back if responder node + * didn't received all packets send by originator. + */ + unsigned int tx; + unsigned int tx_acked; + /* rx - number of packets received */ + unsigned int rx; + /* block - amount of packets expected in one block */ + unsigned int block; + /* dpo - ETP.CM_DPO, Data Packet Offset */ + unsigned int dpo; + } pkt; + struct hrtimer txtimer, rxtimer; +}; + +struct j1939_sock { + struct sock sk; /* must be first to skip with memset */ + struct j1939_priv *priv; + struct list_head list; + +#define J1939_SOCK_BOUND BIT(0) +#define J1939_SOCK_CONNECTED BIT(1) +#define J1939_SOCK_PROMISC BIT(2) +#define J1939_SOCK_ERRQUEUE BIT(3) + int state; + + int ifindex; + struct j1939_addr addr; + struct j1939_filter *filters; + int nfilters; + pgn_t pgn_rx_filter; + + /* j1939 may emit equal PGN (!= equal CAN-id's) out of order + * when transport protocol comes in. + * To allow emitting in order, keep a 'pending' nr. of packets + */ + atomic_t skb_pending; + wait_queue_head_t waitq; + + /* lock for the sk_session_queue list */ + spinlock_t sk_session_queue_lock; + struct list_head sk_session_queue; +}; + +static inline struct j1939_sock *j1939_sk(const struct sock *sk) +{ + return container_of(sk, struct j1939_sock, sk); +} + +void j1939_session_get(struct j1939_session *session); +void j1939_session_put(struct j1939_session *session); +void j1939_session_skb_queue(struct j1939_session *session, + struct sk_buff *skb); +int j1939_session_activate(struct j1939_session *session); +void j1939_tp_schedule_txtimer(struct j1939_session *session, int msec); +void j1939_session_timers_cancel(struct j1939_session *session); + +#define J1939_MAX_TP_PACKET_SIZE (7 * 0xff) +#define J1939_MAX_ETP_PACKET_SIZE (7 * 0x00ffffff) + +#define J1939_REGULAR 0 +#define J1939_EXTENDED 1 + +/* CAN protocol */ +extern const struct can_proto j1939_can_proto; + +#endif /* _J1939_PRIV_H_ */ diff --git a/net/can/j1939/main.c b/net/can/j1939/main.c new file mode 100644 index 000000000000..def2f813ffce --- /dev/null +++ b/net/can/j1939/main.c @@ -0,0 +1,403 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2010-2011 EIA Electronics, +// Pieter Beyens <pieter.beyens@eia.be> +// Copyright (c) 2010-2011 EIA Electronics, +// Kurt Van Dijck <kurt.van.dijck@eia.be> +// Copyright (c) 2018 Protonic, +// Robin van der Gracht <robin@protonic.nl> +// Copyright (c) 2017-2019 Pengutronix, +// Marc Kleine-Budde <kernel@pengutronix.de> +// Copyright (c) 2017-2019 Pengutronix, +// Oleksij Rempel <kernel@pengutronix.de> + +/* Core of can-j1939 that links j1939 to CAN. */ + +#include <linux/can/can-ml.h> +#include <linux/can/core.h> +#include <linux/can/skb.h> +#include <linux/if_arp.h> +#include <linux/module.h> + +#include "j1939-priv.h" + +MODULE_DESCRIPTION("PF_CAN SAE J1939"); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("EIA Electronics (Kurt Van Dijck & Pieter Beyens)"); +MODULE_ALIAS("can-proto-" __stringify(CAN_J1939)); + +/* LOWLEVEL CAN interface */ + +/* CAN_HDR: #bytes before can_frame data part */ +#define J1939_CAN_HDR (offsetof(struct can_frame, data)) + +/* CAN_FTR: #bytes beyond data part */ +#define J1939_CAN_FTR (sizeof(struct can_frame) - J1939_CAN_HDR - \ + sizeof(((struct can_frame *)0)->data)) + +/* lowest layer */ +static void j1939_can_recv(struct sk_buff *iskb, void *data) +{ + struct j1939_priv *priv = data; + struct sk_buff *skb; + struct j1939_sk_buff_cb *skcb, *iskcb; + struct can_frame *cf; + + /* create a copy of the skb + * j1939 only delivers the real data bytes, + * the header goes into sockaddr. + * j1939 may not touch the incoming skb in such way + */ + skb = skb_clone(iskb, GFP_ATOMIC); + if (!skb) + return; + + can_skb_set_owner(skb, iskb->sk); + + /* get a pointer to the header of the skb + * the skb payload (pointer) is moved, so that the next skb_data + * returns the actual payload + */ + cf = (void *)skb->data; + skb_pull(skb, J1939_CAN_HDR); + + /* fix length, set to dlc, with 8 maximum */ + skb_trim(skb, min_t(uint8_t, cf->can_dlc, 8)); + + /* set addr */ + skcb = j1939_skb_to_cb(skb); + memset(skcb, 0, sizeof(*skcb)); + + iskcb = j1939_skb_to_cb(iskb); + skcb->tskey = iskcb->tskey; + skcb->priority = (cf->can_id >> 26) & 0x7; + skcb->addr.sa = cf->can_id; + skcb->addr.pgn = (cf->can_id >> 8) & J1939_PGN_MAX; + /* set default message type */ + skcb->addr.type = J1939_TP; + if (j1939_pgn_is_pdu1(skcb->addr.pgn)) { + /* Type 1: with destination address */ + skcb->addr.da = skcb->addr.pgn; + /* normalize pgn: strip dst address */ + skcb->addr.pgn &= 0x3ff00; + } else { + /* set broadcast address */ + skcb->addr.da = J1939_NO_ADDR; + } + + /* update localflags */ + read_lock_bh(&priv->lock); + if (j1939_address_is_unicast(skcb->addr.sa) && + priv->ents[skcb->addr.sa].nusers) + skcb->flags |= J1939_ECU_LOCAL_SRC; + if (j1939_address_is_unicast(skcb->addr.da) && + priv->ents[skcb->addr.da].nusers) + skcb->flags |= J1939_ECU_LOCAL_DST; + read_unlock_bh(&priv->lock); + + /* deliver into the j1939 stack ... */ + j1939_ac_recv(priv, skb); + + if (j1939_tp_recv(priv, skb)) + /* this means the transport layer processed the message */ + goto done; + + j1939_simple_recv(priv, skb); + j1939_sk_recv(priv, skb); + done: + kfree_skb(skb); +} + +/* NETDEV MANAGEMENT */ + +/* values for can_rx_(un)register */ +#define J1939_CAN_ID CAN_EFF_FLAG +#define J1939_CAN_MASK (CAN_EFF_FLAG | CAN_RTR_FLAG) + +static DEFINE_SPINLOCK(j1939_netdev_lock); + +static struct j1939_priv *j1939_priv_create(struct net_device *ndev) +{ + struct j1939_priv *priv; + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + return NULL; + + rwlock_init(&priv->lock); + INIT_LIST_HEAD(&priv->ecus); + priv->ndev = ndev; + kref_init(&priv->kref); + kref_init(&priv->rx_kref); + dev_hold(ndev); + + netdev_dbg(priv->ndev, "%s : 0x%p\n", __func__, priv); + + return priv; +} + +static inline void j1939_priv_set(struct net_device *ndev, + struct j1939_priv *priv) +{ + struct can_ml_priv *can_ml_priv = ndev->ml_priv; + + can_ml_priv->j1939_priv = priv; +} + +static void __j1939_priv_release(struct kref *kref) +{ + struct j1939_priv *priv = container_of(kref, struct j1939_priv, kref); + struct net_device *ndev = priv->ndev; + + netdev_dbg(priv->ndev, "%s: 0x%p\n", __func__, priv); + + dev_put(ndev); + kfree(priv); +} + +void j1939_priv_put(struct j1939_priv *priv) +{ + kref_put(&priv->kref, __j1939_priv_release); +} + +void j1939_priv_get(struct j1939_priv *priv) +{ + kref_get(&priv->kref); +} + +static int j1939_can_rx_register(struct j1939_priv *priv) +{ + struct net_device *ndev = priv->ndev; + int ret; + + j1939_priv_get(priv); + ret = can_rx_register(dev_net(ndev), ndev, J1939_CAN_ID, J1939_CAN_MASK, + j1939_can_recv, priv, "j1939", NULL); + if (ret < 0) { + j1939_priv_put(priv); + return ret; + } + + return 0; +} + +static void j1939_can_rx_unregister(struct j1939_priv *priv) +{ + struct net_device *ndev = priv->ndev; + + can_rx_unregister(dev_net(ndev), ndev, J1939_CAN_ID, J1939_CAN_MASK, + j1939_can_recv, priv); + + j1939_priv_put(priv); +} + +static void __j1939_rx_release(struct kref *kref) + __releases(&j1939_netdev_lock) +{ + struct j1939_priv *priv = container_of(kref, struct j1939_priv, + rx_kref); + + j1939_can_rx_unregister(priv); + j1939_ecu_unmap_all(priv); + j1939_priv_set(priv->ndev, NULL); + spin_unlock(&j1939_netdev_lock); +} + +/* get pointer to priv without increasing ref counter */ +static inline struct j1939_priv *j1939_ndev_to_priv(struct net_device *ndev) +{ + struct can_ml_priv *can_ml_priv = ndev->ml_priv; + + return can_ml_priv->j1939_priv; +} + +static struct j1939_priv *j1939_priv_get_by_ndev_locked(struct net_device *ndev) +{ + struct j1939_priv *priv; + + lockdep_assert_held(&j1939_netdev_lock); + + if (ndev->type != ARPHRD_CAN) + return NULL; + + priv = j1939_ndev_to_priv(ndev); + if (priv) + j1939_priv_get(priv); + + return priv; +} + +static struct j1939_priv *j1939_priv_get_by_ndev(struct net_device *ndev) +{ + struct j1939_priv *priv; + + spin_lock(&j1939_netdev_lock); + priv = j1939_priv_get_by_ndev_locked(ndev); + spin_unlock(&j1939_netdev_lock); + + return priv; +} + +struct j1939_priv *j1939_netdev_start(struct net_device *ndev) +{ + struct j1939_priv *priv, *priv_new; + int ret; + + priv = j1939_priv_get_by_ndev(ndev); + if (priv) { + kref_get(&priv->rx_kref); + return priv; + } + + priv = j1939_priv_create(ndev); + if (!priv) + return ERR_PTR(-ENOMEM); + + j1939_tp_init(priv); + spin_lock_init(&priv->j1939_socks_lock); + INIT_LIST_HEAD(&priv->j1939_socks); + + spin_lock(&j1939_netdev_lock); + priv_new = j1939_priv_get_by_ndev_locked(ndev); + if (priv_new) { + /* Someone was faster than us, use their priv and roll + * back our's. + */ + spin_unlock(&j1939_netdev_lock); + dev_put(ndev); + kfree(priv); + kref_get(&priv_new->rx_kref); + return priv_new; + } + j1939_priv_set(ndev, priv); + spin_unlock(&j1939_netdev_lock); + + ret = j1939_can_rx_register(priv); + if (ret < 0) + goto out_priv_put; + + return priv; + + out_priv_put: + j1939_priv_set(ndev, NULL); + dev_put(ndev); + kfree(priv); + + return ERR_PTR(ret); +} + +void j1939_netdev_stop(struct j1939_priv *priv) +{ + kref_put_lock(&priv->rx_kref, __j1939_rx_release, &j1939_netdev_lock); + j1939_priv_put(priv); +} + +int j1939_send_one(struct j1939_priv *priv, struct sk_buff *skb) +{ + int ret, dlc; + canid_t canid; + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct can_frame *cf; + + /* apply sanity checks */ + if (j1939_pgn_is_pdu1(skcb->addr.pgn)) + skcb->addr.pgn &= J1939_PGN_PDU1_MAX; + else + skcb->addr.pgn &= J1939_PGN_MAX; + + if (skcb->priority > 7) + skcb->priority = 6; + + ret = j1939_ac_fixup(priv, skb); + if (unlikely(ret)) + goto failed; + dlc = skb->len; + + /* re-claim the CAN_HDR from the SKB */ + cf = skb_push(skb, J1939_CAN_HDR); + + /* make it a full can frame again */ + skb_put(skb, J1939_CAN_FTR + (8 - dlc)); + + canid = CAN_EFF_FLAG | + (skcb->priority << 26) | + (skcb->addr.pgn << 8) | + skcb->addr.sa; + if (j1939_pgn_is_pdu1(skcb->addr.pgn)) + canid |= skcb->addr.da << 8; + + cf->can_id = canid; + cf->can_dlc = dlc; + + return can_send(skb, 1); + + failed: + kfree_skb(skb); + return ret; +} + +static int j1939_netdev_notify(struct notifier_block *nb, + unsigned long msg, void *data) +{ + struct net_device *ndev = netdev_notifier_info_to_dev(data); + struct j1939_priv *priv; + + priv = j1939_priv_get_by_ndev(ndev); + if (!priv) + goto notify_done; + + if (ndev->type != ARPHRD_CAN) + goto notify_put; + + switch (msg) { + case NETDEV_DOWN: + j1939_cancel_active_session(priv, NULL); + j1939_sk_netdev_event_netdown(priv); + j1939_ecu_unmap_all(priv); + break; + } + +notify_put: + j1939_priv_put(priv); + +notify_done: + return NOTIFY_DONE; +} + +static struct notifier_block j1939_netdev_notifier = { + .notifier_call = j1939_netdev_notify, +}; + +/* MODULE interface */ +static __init int j1939_module_init(void) +{ + int ret; + + pr_info("can: SAE J1939\n"); + + ret = register_netdevice_notifier(&j1939_netdev_notifier); + if (ret) + goto fail_notifier; + + ret = can_proto_register(&j1939_can_proto); + if (ret < 0) { + pr_err("can: registration of j1939 protocol failed\n"); + goto fail_sk; + } + + return 0; + + fail_sk: + unregister_netdevice_notifier(&j1939_netdev_notifier); + fail_notifier: + return ret; +} + +static __exit void j1939_module_exit(void) +{ + can_proto_unregister(&j1939_can_proto); + + unregister_netdevice_notifier(&j1939_netdev_notifier); +} + +module_init(j1939_module_init); +module_exit(j1939_module_exit); diff --git a/net/can/j1939/socket.c b/net/can/j1939/socket.c new file mode 100644 index 000000000000..37c1040bcb9c --- /dev/null +++ b/net/can/j1939/socket.c @@ -0,0 +1,1160 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2010-2011 EIA Electronics, +// Pieter Beyens <pieter.beyens@eia.be> +// Copyright (c) 2010-2011 EIA Electronics, +// Kurt Van Dijck <kurt.van.dijck@eia.be> +// Copyright (c) 2018 Protonic, +// Robin van der Gracht <robin@protonic.nl> +// Copyright (c) 2017-2019 Pengutronix, +// Marc Kleine-Budde <kernel@pengutronix.de> +// Copyright (c) 2017-2019 Pengutronix, +// Oleksij Rempel <kernel@pengutronix.de> + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/can/core.h> +#include <linux/can/skb.h> +#include <linux/errqueue.h> +#include <linux/if_arp.h> + +#include "j1939-priv.h" + +#define J1939_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_addr.j1939) + +/* conversion function between struct sock::sk_priority from linux and + * j1939 priority field + */ +static inline priority_t j1939_prio(u32 sk_priority) +{ + sk_priority = min(sk_priority, 7U); + + return 7 - sk_priority; +} + +static inline u32 j1939_to_sk_priority(priority_t prio) +{ + return 7 - prio; +} + +/* function to see if pgn is to be evaluated */ +static inline bool j1939_pgn_is_valid(pgn_t pgn) +{ + return pgn <= J1939_PGN_MAX; +} + +/* test function to avoid non-zero DA placeholder for pdu1 pgn's */ +static inline bool j1939_pgn_is_clean_pdu(pgn_t pgn) +{ + if (j1939_pgn_is_pdu1(pgn)) + return !(pgn & 0xff); + else + return true; +} + +static inline void j1939_sock_pending_add(struct sock *sk) +{ + struct j1939_sock *jsk = j1939_sk(sk); + + atomic_inc(&jsk->skb_pending); +} + +static int j1939_sock_pending_get(struct sock *sk) +{ + struct j1939_sock *jsk = j1939_sk(sk); + + return atomic_read(&jsk->skb_pending); +} + +void j1939_sock_pending_del(struct sock *sk) +{ + struct j1939_sock *jsk = j1939_sk(sk); + + /* atomic_dec_return returns the new value */ + if (!atomic_dec_return(&jsk->skb_pending)) + wake_up(&jsk->waitq); /* no pending SKB's */ +} + +static void j1939_jsk_add(struct j1939_priv *priv, struct j1939_sock *jsk) +{ + jsk->state |= J1939_SOCK_BOUND; + j1939_priv_get(priv); + jsk->priv = priv; + + spin_lock_bh(&priv->j1939_socks_lock); + list_add_tail(&jsk->list, &priv->j1939_socks); + spin_unlock_bh(&priv->j1939_socks_lock); +} + +static void j1939_jsk_del(struct j1939_priv *priv, struct j1939_sock *jsk) +{ + spin_lock_bh(&priv->j1939_socks_lock); + list_del_init(&jsk->list); + spin_unlock_bh(&priv->j1939_socks_lock); + + jsk->priv = NULL; + j1939_priv_put(priv); + jsk->state &= ~J1939_SOCK_BOUND; +} + +static bool j1939_sk_queue_session(struct j1939_session *session) +{ + struct j1939_sock *jsk = j1939_sk(session->sk); + bool empty; + + spin_lock_bh(&jsk->sk_session_queue_lock); + empty = list_empty(&jsk->sk_session_queue); + j1939_session_get(session); + list_add_tail(&session->sk_session_queue_entry, &jsk->sk_session_queue); + spin_unlock_bh(&jsk->sk_session_queue_lock); + j1939_sock_pending_add(&jsk->sk); + + return empty; +} + +static struct +j1939_session *j1939_sk_get_incomplete_session(struct j1939_sock *jsk) +{ + struct j1939_session *session = NULL; + + spin_lock_bh(&jsk->sk_session_queue_lock); + if (!list_empty(&jsk->sk_session_queue)) { + session = list_last_entry(&jsk->sk_session_queue, + struct j1939_session, + sk_session_queue_entry); + if (session->total_queued_size == session->total_message_size) + session = NULL; + else + j1939_session_get(session); + } + spin_unlock_bh(&jsk->sk_session_queue_lock); + + return session; +} + +static void j1939_sk_queue_drop_all(struct j1939_priv *priv, + struct j1939_sock *jsk, int err) +{ + struct j1939_session *session, *tmp; + + netdev_dbg(priv->ndev, "%s: err: %i\n", __func__, err); + spin_lock_bh(&jsk->sk_session_queue_lock); + list_for_each_entry_safe(session, tmp, &jsk->sk_session_queue, + sk_session_queue_entry) { + list_del_init(&session->sk_session_queue_entry); + session->err = err; + j1939_session_put(session); + } + spin_unlock_bh(&jsk->sk_session_queue_lock); +} + +static void j1939_sk_queue_activate_next_locked(struct j1939_session *session) +{ + struct j1939_sock *jsk; + struct j1939_session *first; + int err; + + /* RX-Session don't have a socket (yet) */ + if (!session->sk) + return; + + jsk = j1939_sk(session->sk); + lockdep_assert_held(&jsk->sk_session_queue_lock); + + err = session->err; + + first = list_first_entry_or_null(&jsk->sk_session_queue, + struct j1939_session, + sk_session_queue_entry); + + /* Some else has already activated the next session */ + if (first != session) + return; + +activate_next: + list_del_init(&first->sk_session_queue_entry); + j1939_session_put(first); + first = list_first_entry_or_null(&jsk->sk_session_queue, + struct j1939_session, + sk_session_queue_entry); + if (!first) + return; + + if (WARN_ON_ONCE(j1939_session_activate(first))) { + first->err = -EBUSY; + goto activate_next; + } else { + /* Give receiver some time (arbitrary chosen) to recover */ + int time_ms = 0; + + if (err) + time_ms = 10 + prandom_u32_max(16); + + j1939_tp_schedule_txtimer(first, time_ms); + } +} + +void j1939_sk_queue_activate_next(struct j1939_session *session) +{ + struct j1939_sock *jsk; + + if (!session->sk) + return; + + jsk = j1939_sk(session->sk); + + spin_lock_bh(&jsk->sk_session_queue_lock); + j1939_sk_queue_activate_next_locked(session); + spin_unlock_bh(&jsk->sk_session_queue_lock); +} + +static bool j1939_sk_match_dst(struct j1939_sock *jsk, + const struct j1939_sk_buff_cb *skcb) +{ + if ((jsk->state & J1939_SOCK_PROMISC)) + return true; + + /* Destination address filter */ + if (jsk->addr.src_name && skcb->addr.dst_name) { + if (jsk->addr.src_name != skcb->addr.dst_name) + return false; + } else { + /* receive (all sockets) if + * - all packages that match our bind() address + * - all broadcast on a socket if SO_BROADCAST + * is set + */ + if (j1939_address_is_unicast(skcb->addr.da)) { + if (jsk->addr.sa != skcb->addr.da) + return false; + } else if (!sock_flag(&jsk->sk, SOCK_BROADCAST)) { + /* receiving broadcast without SO_BROADCAST + * flag is not allowed + */ + return false; + } + } + + /* Source address filter */ + if (jsk->state & J1939_SOCK_CONNECTED) { + /* receive (all sockets) if + * - all packages that match our connect() name or address + */ + if (jsk->addr.dst_name && skcb->addr.src_name) { + if (jsk->addr.dst_name != skcb->addr.src_name) + return false; + } else { + if (jsk->addr.da != skcb->addr.sa) + return false; + } + } + + /* PGN filter */ + if (j1939_pgn_is_valid(jsk->pgn_rx_filter) && + jsk->pgn_rx_filter != skcb->addr.pgn) + return false; + + return true; +} + +/* matches skb control buffer (addr) with a j1939 filter */ +static bool j1939_sk_match_filter(struct j1939_sock *jsk, + const struct j1939_sk_buff_cb *skcb) +{ + const struct j1939_filter *f = jsk->filters; + int nfilter = jsk->nfilters; + + if (!nfilter) + /* receive all when no filters are assigned */ + return true; + + for (; nfilter; ++f, --nfilter) { + if ((skcb->addr.pgn & f->pgn_mask) != f->pgn) + continue; + if ((skcb->addr.sa & f->addr_mask) != f->addr) + continue; + if ((skcb->addr.src_name & f->name_mask) != f->name) + continue; + return true; + } + return false; +} + +static bool j1939_sk_recv_match_one(struct j1939_sock *jsk, + const struct j1939_sk_buff_cb *skcb) +{ + if (!(jsk->state & J1939_SOCK_BOUND)) + return false; + + if (!j1939_sk_match_dst(jsk, skcb)) + return false; + + if (!j1939_sk_match_filter(jsk, skcb)) + return false; + + return true; +} + +static void j1939_sk_recv_one(struct j1939_sock *jsk, struct sk_buff *oskb) +{ + const struct j1939_sk_buff_cb *oskcb = j1939_skb_to_cb(oskb); + struct j1939_sk_buff_cb *skcb; + struct sk_buff *skb; + + if (oskb->sk == &jsk->sk) + return; + + if (!j1939_sk_recv_match_one(jsk, oskcb)) + return; + + skb = skb_clone(oskb, GFP_ATOMIC); + if (!skb) { + pr_warn("skb clone failed\n"); + return; + } + can_skb_set_owner(skb, oskb->sk); + + skcb = j1939_skb_to_cb(skb); + skcb->msg_flags &= ~(MSG_DONTROUTE); + if (skb->sk) + skcb->msg_flags |= MSG_DONTROUTE; + + if (sock_queue_rcv_skb(&jsk->sk, skb) < 0) + kfree_skb(skb); +} + +bool j1939_sk_recv_match(struct j1939_priv *priv, struct j1939_sk_buff_cb *skcb) +{ + struct j1939_sock *jsk; + bool match = false; + + spin_lock_bh(&priv->j1939_socks_lock); + list_for_each_entry(jsk, &priv->j1939_socks, list) { + match = j1939_sk_recv_match_one(jsk, skcb); + if (match) + break; + } + spin_unlock_bh(&priv->j1939_socks_lock); + + return match; +} + +void j1939_sk_recv(struct j1939_priv *priv, struct sk_buff *skb) +{ + struct j1939_sock *jsk; + + spin_lock_bh(&priv->j1939_socks_lock); + list_for_each_entry(jsk, &priv->j1939_socks, list) { + j1939_sk_recv_one(jsk, skb); + } + spin_unlock_bh(&priv->j1939_socks_lock); +} + +static int j1939_sk_init(struct sock *sk) +{ + struct j1939_sock *jsk = j1939_sk(sk); + + /* Ensure that "sk" is first member in "struct j1939_sock", so that we + * can skip it during memset(). + */ + BUILD_BUG_ON(offsetof(struct j1939_sock, sk) != 0); + memset((void *)jsk + sizeof(jsk->sk), 0x0, + sizeof(*jsk) - sizeof(jsk->sk)); + + INIT_LIST_HEAD(&jsk->list); + init_waitqueue_head(&jsk->waitq); + jsk->sk.sk_priority = j1939_to_sk_priority(6); + jsk->sk.sk_reuse = 1; /* per default */ + jsk->addr.sa = J1939_NO_ADDR; + jsk->addr.da = J1939_NO_ADDR; + jsk->addr.pgn = J1939_NO_PGN; + jsk->pgn_rx_filter = J1939_NO_PGN; + atomic_set(&jsk->skb_pending, 0); + spin_lock_init(&jsk->sk_session_queue_lock); + INIT_LIST_HEAD(&jsk->sk_session_queue); + + return 0; +} + +static int j1939_sk_sanity_check(struct sockaddr_can *addr, int len) +{ + if (!addr) + return -EDESTADDRREQ; + if (len < J1939_MIN_NAMELEN) + return -EINVAL; + if (addr->can_family != AF_CAN) + return -EINVAL; + if (!addr->can_ifindex) + return -ENODEV; + if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn) && + !j1939_pgn_is_clean_pdu(addr->can_addr.j1939.pgn)) + return -EINVAL; + + return 0; +} + +static int j1939_sk_bind(struct socket *sock, struct sockaddr *uaddr, int len) +{ + struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; + struct j1939_sock *jsk = j1939_sk(sock->sk); + struct j1939_priv *priv = jsk->priv; + struct sock *sk = sock->sk; + struct net *net = sock_net(sk); + int ret = 0; + + ret = j1939_sk_sanity_check(addr, len); + if (ret) + return ret; + + lock_sock(sock->sk); + + /* Already bound to an interface? */ + if (jsk->state & J1939_SOCK_BOUND) { + /* A re-bind() to a different interface is not + * supported. + */ + if (jsk->ifindex != addr->can_ifindex) { + ret = -EINVAL; + goto out_release_sock; + } + + /* drop old references */ + j1939_jsk_del(priv, jsk); + j1939_local_ecu_put(priv, jsk->addr.src_name, jsk->addr.sa); + } else { + struct net_device *ndev; + + ndev = dev_get_by_index(net, addr->can_ifindex); + if (!ndev) { + ret = -ENODEV; + goto out_release_sock; + } + + if (ndev->type != ARPHRD_CAN) { + dev_put(ndev); + ret = -ENODEV; + goto out_release_sock; + } + + priv = j1939_netdev_start(ndev); + dev_put(ndev); + if (IS_ERR(priv)) { + ret = PTR_ERR(priv); + goto out_release_sock; + } + + jsk->ifindex = addr->can_ifindex; + } + + /* set default transmit pgn */ + if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn)) + jsk->pgn_rx_filter = addr->can_addr.j1939.pgn; + jsk->addr.src_name = addr->can_addr.j1939.name; + jsk->addr.sa = addr->can_addr.j1939.addr; + + /* get new references */ + ret = j1939_local_ecu_get(priv, jsk->addr.src_name, jsk->addr.sa); + if (ret) { + j1939_netdev_stop(priv); + goto out_release_sock; + } + + j1939_jsk_add(priv, jsk); + + out_release_sock: /* fall through */ + release_sock(sock->sk); + + return ret; +} + +static int j1939_sk_connect(struct socket *sock, struct sockaddr *uaddr, + int len, int flags) +{ + struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; + struct j1939_sock *jsk = j1939_sk(sock->sk); + int ret = 0; + + ret = j1939_sk_sanity_check(addr, len); + if (ret) + return ret; + + lock_sock(sock->sk); + + /* bind() before connect() is mandatory */ + if (!(jsk->state & J1939_SOCK_BOUND)) { + ret = -EINVAL; + goto out_release_sock; + } + + /* A connect() to a different interface is not supported. */ + if (jsk->ifindex != addr->can_ifindex) { + ret = -EINVAL; + goto out_release_sock; + } + + if (!addr->can_addr.j1939.name && + addr->can_addr.j1939.addr == J1939_NO_ADDR && + !sock_flag(&jsk->sk, SOCK_BROADCAST)) { + /* broadcast, but SO_BROADCAST not set */ + ret = -EACCES; + goto out_release_sock; + } + + jsk->addr.dst_name = addr->can_addr.j1939.name; + jsk->addr.da = addr->can_addr.j1939.addr; + + if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn)) + jsk->addr.pgn = addr->can_addr.j1939.pgn; + + jsk->state |= J1939_SOCK_CONNECTED; + + out_release_sock: /* fall through */ + release_sock(sock->sk); + + return ret; +} + +static void j1939_sk_sock2sockaddr_can(struct sockaddr_can *addr, + const struct j1939_sock *jsk, int peer) +{ + addr->can_family = AF_CAN; + addr->can_ifindex = jsk->ifindex; + addr->can_addr.j1939.pgn = jsk->addr.pgn; + if (peer) { + addr->can_addr.j1939.name = jsk->addr.dst_name; + addr->can_addr.j1939.addr = jsk->addr.da; + } else { + addr->can_addr.j1939.name = jsk->addr.src_name; + addr->can_addr.j1939.addr = jsk->addr.sa; + } +} + +static int j1939_sk_getname(struct socket *sock, struct sockaddr *uaddr, + int peer) +{ + struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; + struct sock *sk = sock->sk; + struct j1939_sock *jsk = j1939_sk(sk); + int ret = 0; + + lock_sock(sk); + + if (peer && !(jsk->state & J1939_SOCK_CONNECTED)) { + ret = -EADDRNOTAVAIL; + goto failure; + } + + j1939_sk_sock2sockaddr_can(addr, jsk, peer); + ret = J1939_MIN_NAMELEN; + + failure: + release_sock(sk); + + return ret; +} + +static int j1939_sk_release(struct socket *sock) +{ + struct sock *sk = sock->sk; + struct j1939_sock *jsk; + + if (!sk) + return 0; + + jsk = j1939_sk(sk); + lock_sock(sk); + + if (jsk->state & J1939_SOCK_BOUND) { + struct j1939_priv *priv = jsk->priv; + + if (wait_event_interruptible(jsk->waitq, + !j1939_sock_pending_get(&jsk->sk))) { + j1939_cancel_active_session(priv, sk); + j1939_sk_queue_drop_all(priv, jsk, ESHUTDOWN); + } + + j1939_jsk_del(priv, jsk); + + j1939_local_ecu_put(priv, jsk->addr.src_name, + jsk->addr.sa); + + j1939_netdev_stop(priv); + } + + sock_orphan(sk); + sock->sk = NULL; + + release_sock(sk); + sock_put(sk); + + return 0; +} + +static int j1939_sk_setsockopt_flag(struct j1939_sock *jsk, char __user *optval, + unsigned int optlen, int flag) +{ + int tmp; + + if (optlen != sizeof(tmp)) + return -EINVAL; + if (copy_from_user(&tmp, optval, optlen)) + return -EFAULT; + lock_sock(&jsk->sk); + if (tmp) + jsk->state |= flag; + else + jsk->state &= ~flag; + release_sock(&jsk->sk); + return tmp; +} + +static int j1939_sk_setsockopt(struct socket *sock, int level, int optname, + char __user *optval, unsigned int optlen) +{ + struct sock *sk = sock->sk; + struct j1939_sock *jsk = j1939_sk(sk); + int tmp, count = 0, ret = 0; + struct j1939_filter *filters = NULL, *ofilters; + + if (level != SOL_CAN_J1939) + return -EINVAL; + + switch (optname) { + case SO_J1939_FILTER: + if (optval) { + struct j1939_filter *f; + int c; + + if (optlen % sizeof(*filters) != 0) + return -EINVAL; + + if (optlen > J1939_FILTER_MAX * + sizeof(struct j1939_filter)) + return -EINVAL; + + count = optlen / sizeof(*filters); + filters = memdup_user(optval, optlen); + if (IS_ERR(filters)) + return PTR_ERR(filters); + + for (f = filters, c = count; c; f++, c--) { + f->name &= f->name_mask; + f->pgn &= f->pgn_mask; + f->addr &= f->addr_mask; + } + } + + lock_sock(&jsk->sk); + ofilters = jsk->filters; + jsk->filters = filters; + jsk->nfilters = count; + release_sock(&jsk->sk); + kfree(ofilters); + return 0; + case SO_J1939_PROMISC: + return j1939_sk_setsockopt_flag(jsk, optval, optlen, + J1939_SOCK_PROMISC); + case SO_J1939_ERRQUEUE: + ret = j1939_sk_setsockopt_flag(jsk, optval, optlen, + J1939_SOCK_ERRQUEUE); + if (ret < 0) + return ret; + + if (!(jsk->state & J1939_SOCK_ERRQUEUE)) + skb_queue_purge(&sk->sk_error_queue); + return ret; + case SO_J1939_SEND_PRIO: + if (optlen != sizeof(tmp)) + return -EINVAL; + if (copy_from_user(&tmp, optval, optlen)) + return -EFAULT; + if (tmp < 0 || tmp > 7) + return -EDOM; + if (tmp < 2 && !capable(CAP_NET_ADMIN)) + return -EPERM; + lock_sock(&jsk->sk); + jsk->sk.sk_priority = j1939_to_sk_priority(tmp); + release_sock(&jsk->sk); + return 0; + default: + return -ENOPROTOOPT; + } +} + +static int j1939_sk_getsockopt(struct socket *sock, int level, int optname, + char __user *optval, int __user *optlen) +{ + struct sock *sk = sock->sk; + struct j1939_sock *jsk = j1939_sk(sk); + int ret, ulen; + /* set defaults for using 'int' properties */ + int tmp = 0; + int len = sizeof(tmp); + void *val = &tmp; + + if (level != SOL_CAN_J1939) + return -EINVAL; + if (get_user(ulen, optlen)) + return -EFAULT; + if (ulen < 0) + return -EINVAL; + + lock_sock(&jsk->sk); + switch (optname) { + case SO_J1939_PROMISC: + tmp = (jsk->state & J1939_SOCK_PROMISC) ? 1 : 0; + break; + case SO_J1939_ERRQUEUE: + tmp = (jsk->state & J1939_SOCK_ERRQUEUE) ? 1 : 0; + break; + case SO_J1939_SEND_PRIO: + tmp = j1939_prio(jsk->sk.sk_priority); + break; + default: + ret = -ENOPROTOOPT; + goto no_copy; + } + + /* copy to user, based on 'len' & 'val' + * but most sockopt's are 'int' properties, and have 'len' & 'val' + * left unchanged, but instead modified 'tmp' + */ + if (len > ulen) + ret = -EFAULT; + else if (put_user(len, optlen)) + ret = -EFAULT; + else if (copy_to_user(optval, val, len)) + ret = -EFAULT; + else + ret = 0; + no_copy: + release_sock(&jsk->sk); + return ret; +} + +static int j1939_sk_recvmsg(struct socket *sock, struct msghdr *msg, + size_t size, int flags) +{ + struct sock *sk = sock->sk; + struct sk_buff *skb; + struct j1939_sk_buff_cb *skcb; + int ret = 0; + + if (flags & ~(MSG_DONTWAIT | MSG_ERRQUEUE)) + return -EINVAL; + + if (flags & MSG_ERRQUEUE) + return sock_recv_errqueue(sock->sk, msg, size, SOL_CAN_J1939, + SCM_J1939_ERRQUEUE); + + skb = skb_recv_datagram(sk, flags, 0, &ret); + if (!skb) + return ret; + + if (size < skb->len) + msg->msg_flags |= MSG_TRUNC; + else + size = skb->len; + + ret = memcpy_to_msg(msg, skb->data, size); + if (ret < 0) { + skb_free_datagram(sk, skb); + return ret; + } + + skcb = j1939_skb_to_cb(skb); + if (j1939_address_is_valid(skcb->addr.da)) + put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_DEST_ADDR, + sizeof(skcb->addr.da), &skcb->addr.da); + + if (skcb->addr.dst_name) + put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_DEST_NAME, + sizeof(skcb->addr.dst_name), &skcb->addr.dst_name); + + put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_PRIO, + sizeof(skcb->priority), &skcb->priority); + + if (msg->msg_name) { + struct sockaddr_can *paddr = msg->msg_name; + + msg->msg_namelen = J1939_MIN_NAMELEN; + memset(msg->msg_name, 0, msg->msg_namelen); + paddr->can_family = AF_CAN; + paddr->can_ifindex = skb->skb_iif; + paddr->can_addr.j1939.name = skcb->addr.src_name; + paddr->can_addr.j1939.addr = skcb->addr.sa; + paddr->can_addr.j1939.pgn = skcb->addr.pgn; + } + + sock_recv_ts_and_drops(msg, sk, skb); + msg->msg_flags |= skcb->msg_flags; + skb_free_datagram(sk, skb); + + return size; +} + +static struct sk_buff *j1939_sk_alloc_skb(struct net_device *ndev, + struct sock *sk, + struct msghdr *msg, size_t size, + int *errcode) +{ + struct j1939_sock *jsk = j1939_sk(sk); + struct j1939_sk_buff_cb *skcb; + struct sk_buff *skb; + int ret; + + skb = sock_alloc_send_skb(sk, + size + + sizeof(struct can_frame) - + sizeof(((struct can_frame *)NULL)->data) + + sizeof(struct can_skb_priv), + msg->msg_flags & MSG_DONTWAIT, &ret); + if (!skb) + goto failure; + + can_skb_reserve(skb); + can_skb_prv(skb)->ifindex = ndev->ifindex; + can_skb_prv(skb)->skbcnt = 0; + skb_reserve(skb, offsetof(struct can_frame, data)); + + ret = memcpy_from_msg(skb_put(skb, size), msg, size); + if (ret < 0) + goto free_skb; + + skb->dev = ndev; + + skcb = j1939_skb_to_cb(skb); + memset(skcb, 0, sizeof(*skcb)); + skcb->addr = jsk->addr; + skcb->priority = j1939_prio(sk->sk_priority); + + if (msg->msg_name) { + struct sockaddr_can *addr = msg->msg_name; + + if (addr->can_addr.j1939.name || + addr->can_addr.j1939.addr != J1939_NO_ADDR) { + skcb->addr.dst_name = addr->can_addr.j1939.name; + skcb->addr.da = addr->can_addr.j1939.addr; + } + if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn)) + skcb->addr.pgn = addr->can_addr.j1939.pgn; + } + + *errcode = ret; + return skb; + +free_skb: + kfree_skb(skb); +failure: + *errcode = ret; + return NULL; +} + +static size_t j1939_sk_opt_stats_get_size(void) +{ + return + nla_total_size(sizeof(u32)) + /* J1939_NLA_BYTES_ACKED */ + 0; +} + +static struct sk_buff * +j1939_sk_get_timestamping_opt_stats(struct j1939_session *session) +{ + struct sk_buff *stats; + u32 size; + + stats = alloc_skb(j1939_sk_opt_stats_get_size(), GFP_ATOMIC); + if (!stats) + return NULL; + + if (session->skcb.addr.type == J1939_SIMPLE) + size = session->total_message_size; + else + size = min(session->pkt.tx_acked * 7, + session->total_message_size); + + nla_put_u32(stats, J1939_NLA_BYTES_ACKED, size); + + return stats; +} + +void j1939_sk_errqueue(struct j1939_session *session, + enum j1939_sk_errqueue_type type) +{ + struct j1939_priv *priv = session->priv; + struct sock *sk = session->sk; + struct j1939_sock *jsk; + struct sock_exterr_skb *serr; + struct sk_buff *skb; + char *state = "UNK"; + int err; + + /* currently we have no sk for the RX session */ + if (!sk) + return; + + jsk = j1939_sk(sk); + + if (!(jsk->state & J1939_SOCK_ERRQUEUE)) + return; + + skb = j1939_sk_get_timestamping_opt_stats(session); + if (!skb) + return; + + skb->tstamp = ktime_get_real(); + + BUILD_BUG_ON(sizeof(struct sock_exterr_skb) > sizeof(skb->cb)); + + serr = SKB_EXT_ERR(skb); + memset(serr, 0, sizeof(*serr)); + switch (type) { + case J1939_ERRQUEUE_ACK: + if (!(sk->sk_tsflags & SOF_TIMESTAMPING_TX_ACK)) + return; + + serr->ee.ee_errno = ENOMSG; + serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING; + serr->ee.ee_info = SCM_TSTAMP_ACK; + state = "ACK"; + break; + case J1939_ERRQUEUE_SCHED: + if (!(sk->sk_tsflags & SOF_TIMESTAMPING_TX_SCHED)) + return; + + serr->ee.ee_errno = ENOMSG; + serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING; + serr->ee.ee_info = SCM_TSTAMP_SCHED; + state = "SCH"; + break; + case J1939_ERRQUEUE_ABORT: + serr->ee.ee_errno = session->err; + serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL; + serr->ee.ee_info = J1939_EE_INFO_TX_ABORT; + state = "ABT"; + break; + default: + netdev_err(priv->ndev, "Unknown errqueue type %i\n", type); + } + + serr->opt_stats = true; + if (sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID) + serr->ee.ee_data = session->tskey; + + netdev_dbg(session->priv->ndev, "%s: 0x%p tskey: %i, state: %s\n", + __func__, session, session->tskey, state); + err = sock_queue_err_skb(sk, skb); + + if (err) + kfree_skb(skb); +}; + +void j1939_sk_send_loop_abort(struct sock *sk, int err) +{ + sk->sk_err = err; + + sk->sk_error_report(sk); +} + +static int j1939_sk_send_loop(struct j1939_priv *priv, struct sock *sk, + struct msghdr *msg, size_t size) + +{ + struct j1939_sock *jsk = j1939_sk(sk); + struct j1939_session *session = j1939_sk_get_incomplete_session(jsk); + struct sk_buff *skb; + size_t segment_size, todo_size; + int ret = 0; + + if (session && + session->total_message_size != session->total_queued_size + size) { + j1939_session_put(session); + return -EIO; + } + + todo_size = size; + + while (todo_size) { + struct j1939_sk_buff_cb *skcb; + + segment_size = min_t(size_t, J1939_MAX_TP_PACKET_SIZE, + todo_size); + + /* Allocate skb for one segment */ + skb = j1939_sk_alloc_skb(priv->ndev, sk, msg, segment_size, + &ret); + if (ret) + break; + + skcb = j1939_skb_to_cb(skb); + + if (!session) { + /* at this point the size should be full size + * of the session + */ + skcb->offset = 0; + session = j1939_tp_send(priv, skb, size); + if (IS_ERR(session)) { + ret = PTR_ERR(session); + goto kfree_skb; + } + if (j1939_sk_queue_session(session)) { + /* try to activate session if we a + * fist in the queue + */ + if (!j1939_session_activate(session)) { + j1939_tp_schedule_txtimer(session, 0); + } else { + ret = -EBUSY; + session->err = ret; + j1939_sk_queue_drop_all(priv, jsk, + EBUSY); + break; + } + } + } else { + skcb->offset = session->total_queued_size; + j1939_session_skb_queue(session, skb); + } + + todo_size -= segment_size; + session->total_queued_size += segment_size; + } + + switch (ret) { + case 0: /* OK */ + if (todo_size) + netdev_warn(priv->ndev, + "no error found and not completely queued?! %zu\n", + todo_size); + ret = size; + break; + case -ERESTARTSYS: + ret = -EINTR; + /* fall through */ + case -EAGAIN: /* OK */ + if (todo_size != size) + ret = size - todo_size; + break; + default: /* ERROR */ + break; + } + + if (session) + j1939_session_put(session); + + return ret; + + kfree_skb: + kfree_skb(skb); + return ret; +} + +static int j1939_sk_sendmsg(struct socket *sock, struct msghdr *msg, + size_t size) +{ + struct sock *sk = sock->sk; + struct j1939_sock *jsk = j1939_sk(sk); + struct j1939_priv *priv = jsk->priv; + int ifindex; + int ret; + + /* various socket state tests */ + if (!(jsk->state & J1939_SOCK_BOUND)) + return -EBADFD; + + ifindex = jsk->ifindex; + + if (!jsk->addr.src_name && jsk->addr.sa == J1939_NO_ADDR) + /* no source address assigned yet */ + return -EBADFD; + + /* deal with provided destination address info */ + if (msg->msg_name) { + struct sockaddr_can *addr = msg->msg_name; + + if (msg->msg_namelen < J1939_MIN_NAMELEN) + return -EINVAL; + + if (addr->can_family != AF_CAN) + return -EINVAL; + + if (addr->can_ifindex && addr->can_ifindex != ifindex) + return -EBADFD; + + if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn) && + !j1939_pgn_is_clean_pdu(addr->can_addr.j1939.pgn)) + return -EINVAL; + + if (!addr->can_addr.j1939.name && + addr->can_addr.j1939.addr == J1939_NO_ADDR && + !sock_flag(sk, SOCK_BROADCAST)) + /* broadcast, but SO_BROADCAST not set */ + return -EACCES; + } else { + if (!jsk->addr.dst_name && jsk->addr.da == J1939_NO_ADDR && + !sock_flag(sk, SOCK_BROADCAST)) + /* broadcast, but SO_BROADCAST not set */ + return -EACCES; + } + + ret = j1939_sk_send_loop(priv, sk, msg, size); + + return ret; +} + +void j1939_sk_netdev_event_netdown(struct j1939_priv *priv) +{ + struct j1939_sock *jsk; + int error_code = ENETDOWN; + + spin_lock_bh(&priv->j1939_socks_lock); + list_for_each_entry(jsk, &priv->j1939_socks, list) { + jsk->sk.sk_err = error_code; + if (!sock_flag(&jsk->sk, SOCK_DEAD)) + jsk->sk.sk_error_report(&jsk->sk); + + j1939_sk_queue_drop_all(priv, jsk, error_code); + } + spin_unlock_bh(&priv->j1939_socks_lock); +} + +static int j1939_sk_no_ioctlcmd(struct socket *sock, unsigned int cmd, + unsigned long arg) +{ + /* no ioctls for socket layer -> hand it down to NIC layer */ + return -ENOIOCTLCMD; +} + +static const struct proto_ops j1939_ops = { + .family = PF_CAN, + .release = j1939_sk_release, + .bind = j1939_sk_bind, + .connect = j1939_sk_connect, + .socketpair = sock_no_socketpair, + .accept = sock_no_accept, + .getname = j1939_sk_getname, + .poll = datagram_poll, + .ioctl = j1939_sk_no_ioctlcmd, + .listen = sock_no_listen, + .shutdown = sock_no_shutdown, + .setsockopt = j1939_sk_setsockopt, + .getsockopt = j1939_sk_getsockopt, + .sendmsg = j1939_sk_sendmsg, + .recvmsg = j1939_sk_recvmsg, + .mmap = sock_no_mmap, + .sendpage = sock_no_sendpage, +}; + +static struct proto j1939_proto __read_mostly = { + .name = "CAN_J1939", + .owner = THIS_MODULE, + .obj_size = sizeof(struct j1939_sock), + .init = j1939_sk_init, +}; + +const struct can_proto j1939_can_proto = { + .type = SOCK_DGRAM, + .protocol = CAN_J1939, + .ops = &j1939_ops, + .prot = &j1939_proto, +}; diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c new file mode 100644 index 000000000000..fe000ea757ea --- /dev/null +++ b/net/can/j1939/transport.c @@ -0,0 +1,2027 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2010-2011 EIA Electronics, +// Kurt Van Dijck <kurt.van.dijck@eia.be> +// Copyright (c) 2018 Protonic, +// Robin van der Gracht <robin@protonic.nl> +// Copyright (c) 2017-2019 Pengutronix, +// Marc Kleine-Budde <kernel@pengutronix.de> +// Copyright (c) 2017-2019 Pengutronix, +// Oleksij Rempel <kernel@pengutronix.de> + +#include <linux/can/skb.h> + +#include "j1939-priv.h" + +#define J1939_XTP_TX_RETRY_LIMIT 100 + +#define J1939_ETP_PGN_CTL 0xc800 +#define J1939_ETP_PGN_DAT 0xc700 +#define J1939_TP_PGN_CTL 0xec00 +#define J1939_TP_PGN_DAT 0xeb00 + +#define J1939_TP_CMD_RTS 0x10 +#define J1939_TP_CMD_CTS 0x11 +#define J1939_TP_CMD_EOMA 0x13 +#define J1939_TP_CMD_BAM 0x20 +#define J1939_TP_CMD_ABORT 0xff + +#define J1939_ETP_CMD_RTS 0x14 +#define J1939_ETP_CMD_CTS 0x15 +#define J1939_ETP_CMD_DPO 0x16 +#define J1939_ETP_CMD_EOMA 0x17 +#define J1939_ETP_CMD_ABORT 0xff + +enum j1939_xtp_abort { + J1939_XTP_NO_ABORT = 0, + J1939_XTP_ABORT_BUSY = 1, + /* Already in one or more connection managed sessions and + * cannot support another. + * + * EALREADY: + * Operation already in progress + */ + + J1939_XTP_ABORT_RESOURCE = 2, + /* System resources were needed for another task so this + * connection managed session was terminated. + * + * EMSGSIZE: + * The socket type requires that message be sent atomically, + * and the size of the message to be sent made this + * impossible. + */ + + J1939_XTP_ABORT_TIMEOUT = 3, + /* A timeout occurred and this is the connection abort to + * close the session. + * + * EHOSTUNREACH: + * The destination host cannot be reached (probably because + * the host is down or a remote router cannot reach it). + */ + + J1939_XTP_ABORT_GENERIC = 4, + /* CTS messages received when data transfer is in progress + * + * EBADMSG: + * Not a data message + */ + + J1939_XTP_ABORT_FAULT = 5, + /* Maximal retransmit request limit reached + * + * ENOTRECOVERABLE: + * State not recoverable + */ + + J1939_XTP_ABORT_UNEXPECTED_DATA = 6, + /* Unexpected data transfer packet + * + * ENOTCONN: + * Transport endpoint is not connected + */ + + J1939_XTP_ABORT_BAD_SEQ = 7, + /* Bad sequence number (and software is not able to recover) + * + * EILSEQ: + * Illegal byte sequence + */ + + J1939_XTP_ABORT_DUP_SEQ = 8, + /* Duplicate sequence number (and software is not able to + * recover) + */ + + J1939_XTP_ABORT_EDPO_UNEXPECTED = 9, + /* Unexpected EDPO packet (ETP) or Message size > 1785 bytes + * (TP) + */ + + J1939_XTP_ABORT_BAD_EDPO_PGN = 10, + /* Unexpected EDPO PGN (PGN in EDPO is bad) */ + + J1939_XTP_ABORT_EDPO_OUTOF_CTS = 11, + /* EDPO number of packets is greater than CTS */ + + J1939_XTP_ABORT_BAD_EDPO_OFFSET = 12, + /* Bad EDPO offset */ + + J1939_XTP_ABORT_OTHER_DEPRECATED = 13, + /* Deprecated. Use 250 instead (Any other reason) */ + + J1939_XTP_ABORT_ECTS_UNXPECTED_PGN = 14, + /* Unexpected ECTS PGN (PGN in ECTS is bad) */ + + J1939_XTP_ABORT_ECTS_TOO_BIG = 15, + /* ECTS requested packets exceeds message size */ + + J1939_XTP_ABORT_OTHER = 250, + /* Any other reason (if a Connection Abort reason is + * identified that is not listed in the table use code 250) + */ +}; + +static unsigned int j1939_tp_block = 255; +static unsigned int j1939_tp_packet_delay; +static unsigned int j1939_tp_padding = 1; + +/* helpers */ +static const char *j1939_xtp_abort_to_str(enum j1939_xtp_abort abort) +{ + switch (abort) { + case J1939_XTP_ABORT_BUSY: + return "Already in one or more connection managed sessions and cannot support another."; + case J1939_XTP_ABORT_RESOURCE: + return "System resources were needed for another task so this connection managed session was terminated."; + case J1939_XTP_ABORT_TIMEOUT: + return "A timeout occurred and this is the connection abort to close the session."; + case J1939_XTP_ABORT_GENERIC: + return "CTS messages received when data transfer is in progress"; + case J1939_XTP_ABORT_FAULT: + return "Maximal retransmit request limit reached"; + case J1939_XTP_ABORT_UNEXPECTED_DATA: + return "Unexpected data transfer packet"; + case J1939_XTP_ABORT_BAD_SEQ: + return "Bad sequence number (and software is not able to recover)"; + case J1939_XTP_ABORT_DUP_SEQ: + return "Duplicate sequence number (and software is not able to recover)"; + case J1939_XTP_ABORT_EDPO_UNEXPECTED: + return "Unexpected EDPO packet (ETP) or Message size > 1785 bytes (TP)"; + case J1939_XTP_ABORT_BAD_EDPO_PGN: + return "Unexpected EDPO PGN (PGN in EDPO is bad)"; + case J1939_XTP_ABORT_EDPO_OUTOF_CTS: + return "EDPO number of packets is greater than CTS"; + case J1939_XTP_ABORT_BAD_EDPO_OFFSET: + return "Bad EDPO offset"; + case J1939_XTP_ABORT_OTHER_DEPRECATED: + return "Deprecated. Use 250 instead (Any other reason)"; + case J1939_XTP_ABORT_ECTS_UNXPECTED_PGN: + return "Unexpected ECTS PGN (PGN in ECTS is bad)"; + case J1939_XTP_ABORT_ECTS_TOO_BIG: + return "ECTS requested packets exceeds message size"; + case J1939_XTP_ABORT_OTHER: + return "Any other reason (if a Connection Abort reason is identified that is not listed in the table use code 250)"; + default: + return "<unknown>"; + } +} + +static int j1939_xtp_abort_to_errno(struct j1939_priv *priv, + enum j1939_xtp_abort abort) +{ + int err; + + switch (abort) { + case J1939_XTP_NO_ABORT: + WARN_ON_ONCE(abort == J1939_XTP_NO_ABORT); + err = 0; + break; + case J1939_XTP_ABORT_BUSY: + err = EALREADY; + break; + case J1939_XTP_ABORT_RESOURCE: + err = EMSGSIZE; + break; + case J1939_XTP_ABORT_TIMEOUT: + err = EHOSTUNREACH; + break; + case J1939_XTP_ABORT_GENERIC: + err = EBADMSG; + break; + case J1939_XTP_ABORT_FAULT: + err = ENOTRECOVERABLE; + break; + case J1939_XTP_ABORT_UNEXPECTED_DATA: + err = ENOTCONN; + break; + case J1939_XTP_ABORT_BAD_SEQ: + err = EILSEQ; + break; + case J1939_XTP_ABORT_DUP_SEQ: + err = EPROTO; + break; + case J1939_XTP_ABORT_EDPO_UNEXPECTED: + err = EPROTO; + break; + case J1939_XTP_ABORT_BAD_EDPO_PGN: + err = EPROTO; + break; + case J1939_XTP_ABORT_EDPO_OUTOF_CTS: + err = EPROTO; + break; + case J1939_XTP_ABORT_BAD_EDPO_OFFSET: + err = EPROTO; + break; + case J1939_XTP_ABORT_OTHER_DEPRECATED: + err = EPROTO; + break; + case J1939_XTP_ABORT_ECTS_UNXPECTED_PGN: + err = EPROTO; + break; + case J1939_XTP_ABORT_ECTS_TOO_BIG: + err = EPROTO; + break; + case J1939_XTP_ABORT_OTHER: + err = EPROTO; + break; + default: + netdev_warn(priv->ndev, "Unknown abort code %i", abort); + err = EPROTO; + } + + return err; +} + +static inline void j1939_session_list_lock(struct j1939_priv *priv) +{ + spin_lock_bh(&priv->active_session_list_lock); +} + +static inline void j1939_session_list_unlock(struct j1939_priv *priv) +{ + spin_unlock_bh(&priv->active_session_list_lock); +} + +void j1939_session_get(struct j1939_session *session) +{ + kref_get(&session->kref); +} + +/* session completion functions */ +static void __j1939_session_drop(struct j1939_session *session) +{ + if (!session->transmission) + return; + + j1939_sock_pending_del(session->sk); +} + +static void j1939_session_destroy(struct j1939_session *session) +{ + if (session->err) + j1939_sk_errqueue(session, J1939_ERRQUEUE_ABORT); + else + j1939_sk_errqueue(session, J1939_ERRQUEUE_ACK); + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + skb_queue_purge(&session->skb_queue); + __j1939_session_drop(session); + j1939_priv_put(session->priv); + kfree(session); +} + +static void __j1939_session_release(struct kref *kref) +{ + struct j1939_session *session = container_of(kref, struct j1939_session, + kref); + + j1939_session_destroy(session); +} + +void j1939_session_put(struct j1939_session *session) +{ + kref_put(&session->kref, __j1939_session_release); +} + +static void j1939_session_txtimer_cancel(struct j1939_session *session) +{ + if (hrtimer_cancel(&session->txtimer)) + j1939_session_put(session); +} + +static void j1939_session_rxtimer_cancel(struct j1939_session *session) +{ + if (hrtimer_cancel(&session->rxtimer)) + j1939_session_put(session); +} + +void j1939_session_timers_cancel(struct j1939_session *session) +{ + j1939_session_txtimer_cancel(session); + j1939_session_rxtimer_cancel(session); +} + +static inline bool j1939_cb_is_broadcast(const struct j1939_sk_buff_cb *skcb) +{ + return (!skcb->addr.dst_name && (skcb->addr.da == 0xff)); +} + +static void j1939_session_skb_drop_old(struct j1939_session *session) +{ + struct sk_buff *do_skb; + struct j1939_sk_buff_cb *do_skcb; + unsigned int offset_start; + unsigned long flags; + + if (skb_queue_len(&session->skb_queue) < 2) + return; + + offset_start = session->pkt.tx_acked * 7; + + spin_lock_irqsave(&session->skb_queue.lock, flags); + do_skb = skb_peek(&session->skb_queue); + do_skcb = j1939_skb_to_cb(do_skb); + + if ((do_skcb->offset + do_skb->len) < offset_start) { + __skb_unlink(do_skb, &session->skb_queue); + kfree_skb(do_skb); + } + spin_unlock_irqrestore(&session->skb_queue.lock, flags); +} + +void j1939_session_skb_queue(struct j1939_session *session, + struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_priv *priv = session->priv; + + j1939_ac_fixup(priv, skb); + + if (j1939_address_is_unicast(skcb->addr.da) && + priv->ents[skcb->addr.da].nusers) + skcb->flags |= J1939_ECU_LOCAL_DST; + + skcb->flags |= J1939_ECU_LOCAL_SRC; + + skb_queue_tail(&session->skb_queue, skb); +} + +static struct sk_buff *j1939_session_skb_find(struct j1939_session *session) +{ + struct j1939_priv *priv = session->priv; + struct sk_buff *skb = NULL; + struct sk_buff *do_skb; + struct j1939_sk_buff_cb *do_skcb; + unsigned int offset_start; + unsigned long flags; + + offset_start = session->pkt.dpo * 7; + + spin_lock_irqsave(&session->skb_queue.lock, flags); + skb_queue_walk(&session->skb_queue, do_skb) { + do_skcb = j1939_skb_to_cb(do_skb); + + if (offset_start >= do_skcb->offset && + offset_start < (do_skcb->offset + do_skb->len)) { + skb = do_skb; + } + } + spin_unlock_irqrestore(&session->skb_queue.lock, flags); + + if (!skb) + netdev_dbg(priv->ndev, "%s: 0x%p: no skb found for start: %i, queue size: %i\n", + __func__, session, offset_start, + skb_queue_len(&session->skb_queue)); + + return skb; +} + +/* see if we are receiver + * returns 0 for broadcasts, although we will receive them + */ +static inline int j1939_tp_im_receiver(const struct j1939_sk_buff_cb *skcb) +{ + return skcb->flags & J1939_ECU_LOCAL_DST; +} + +/* see if we are sender */ +static inline int j1939_tp_im_transmitter(const struct j1939_sk_buff_cb *skcb) +{ + return skcb->flags & J1939_ECU_LOCAL_SRC; +} + +/* see if we are involved as either receiver or transmitter */ +static int j1939_tp_im_involved(const struct j1939_sk_buff_cb *skcb, bool swap) +{ + if (swap) + return j1939_tp_im_receiver(skcb); + else + return j1939_tp_im_transmitter(skcb); +} + +static int j1939_tp_im_involved_anydir(struct j1939_sk_buff_cb *skcb) +{ + return skcb->flags & (J1939_ECU_LOCAL_SRC | J1939_ECU_LOCAL_DST); +} + +/* extract pgn from flow-ctl message */ +static inline pgn_t j1939_xtp_ctl_to_pgn(const u8 *dat) +{ + pgn_t pgn; + + pgn = (dat[7] << 16) | (dat[6] << 8) | (dat[5] << 0); + if (j1939_pgn_is_pdu1(pgn)) + pgn &= 0xffff00; + return pgn; +} + +static inline unsigned int j1939_tp_ctl_to_size(const u8 *dat) +{ + return (dat[2] << 8) + (dat[1] << 0); +} + +static inline unsigned int j1939_etp_ctl_to_packet(const u8 *dat) +{ + return (dat[4] << 16) | (dat[3] << 8) | (dat[2] << 0); +} + +static inline unsigned int j1939_etp_ctl_to_size(const u8 *dat) +{ + return (dat[4] << 24) | (dat[3] << 16) | + (dat[2] << 8) | (dat[1] << 0); +} + +/* find existing session: + * reverse: swap cb's src & dst + * there is no problem with matching broadcasts, since + * broadcasts (no dst, no da) would never call this + * with reverse == true + */ +static bool j1939_session_match(struct j1939_addr *se_addr, + struct j1939_addr *sk_addr, bool reverse) +{ + if (se_addr->type != sk_addr->type) + return false; + + if (reverse) { + if (se_addr->src_name) { + if (se_addr->src_name != sk_addr->dst_name) + return false; + } else if (se_addr->sa != sk_addr->da) { + return false; + } + + if (se_addr->dst_name) { + if (se_addr->dst_name != sk_addr->src_name) + return false; + } else if (se_addr->da != sk_addr->sa) { + return false; + } + } else { + if (se_addr->src_name) { + if (se_addr->src_name != sk_addr->src_name) + return false; + } else if (se_addr->sa != sk_addr->sa) { + return false; + } + + if (se_addr->dst_name) { + if (se_addr->dst_name != sk_addr->dst_name) + return false; + } else if (se_addr->da != sk_addr->da) { + return false; + } + } + + return true; +} + +static struct +j1939_session *j1939_session_get_by_addr_locked(struct j1939_priv *priv, + struct list_head *root, + struct j1939_addr *addr, + bool reverse, bool transmitter) +{ + struct j1939_session *session; + + lockdep_assert_held(&priv->active_session_list_lock); + + list_for_each_entry(session, root, active_session_list_entry) { + j1939_session_get(session); + if (j1939_session_match(&session->skcb.addr, addr, reverse) && + session->transmission == transmitter) + return session; + j1939_session_put(session); + } + + return NULL; +} + +static struct +j1939_session *j1939_session_get_simple(struct j1939_priv *priv, + struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_session *session; + + lockdep_assert_held(&priv->active_session_list_lock); + + list_for_each_entry(session, &priv->active_session_list, + active_session_list_entry) { + j1939_session_get(session); + if (session->skcb.addr.type == J1939_SIMPLE && + session->tskey == skcb->tskey && session->sk == skb->sk) + return session; + j1939_session_put(session); + } + + return NULL; +} + +static struct +j1939_session *j1939_session_get_by_addr(struct j1939_priv *priv, + struct j1939_addr *addr, + bool reverse, bool transmitter) +{ + struct j1939_session *session; + + j1939_session_list_lock(priv); + session = j1939_session_get_by_addr_locked(priv, + &priv->active_session_list, + addr, reverse, transmitter); + j1939_session_list_unlock(priv); + + return session; +} + +static void j1939_skbcb_swap(struct j1939_sk_buff_cb *skcb) +{ + u8 tmp = 0; + + swap(skcb->addr.dst_name, skcb->addr.src_name); + swap(skcb->addr.da, skcb->addr.sa); + + /* swap SRC and DST flags, leave other untouched */ + if (skcb->flags & J1939_ECU_LOCAL_SRC) + tmp |= J1939_ECU_LOCAL_DST; + if (skcb->flags & J1939_ECU_LOCAL_DST) + tmp |= J1939_ECU_LOCAL_SRC; + skcb->flags &= ~(J1939_ECU_LOCAL_SRC | J1939_ECU_LOCAL_DST); + skcb->flags |= tmp; +} + +static struct +sk_buff *j1939_tp_tx_dat_new(struct j1939_priv *priv, + const struct j1939_sk_buff_cb *re_skcb, + bool ctl, + bool swap_src_dst) +{ + struct sk_buff *skb; + struct j1939_sk_buff_cb *skcb; + + skb = alloc_skb(sizeof(struct can_frame) + sizeof(struct can_skb_priv), + GFP_ATOMIC); + if (unlikely(!skb)) + return ERR_PTR(-ENOMEM); + + skb->dev = priv->ndev; + can_skb_reserve(skb); + can_skb_prv(skb)->ifindex = priv->ndev->ifindex; + /* reserve CAN header */ + skb_reserve(skb, offsetof(struct can_frame, data)); + + memcpy(skb->cb, re_skcb, sizeof(skb->cb)); + skcb = j1939_skb_to_cb(skb); + if (swap_src_dst) + j1939_skbcb_swap(skcb); + + if (ctl) { + if (skcb->addr.type == J1939_ETP) + skcb->addr.pgn = J1939_ETP_PGN_CTL; + else + skcb->addr.pgn = J1939_TP_PGN_CTL; + } else { + if (skcb->addr.type == J1939_ETP) + skcb->addr.pgn = J1939_ETP_PGN_DAT; + else + skcb->addr.pgn = J1939_TP_PGN_DAT; + } + + return skb; +} + +/* TP transmit packet functions */ +static int j1939_tp_tx_dat(struct j1939_session *session, + const u8 *dat, int len) +{ + struct j1939_priv *priv = session->priv; + struct sk_buff *skb; + + skb = j1939_tp_tx_dat_new(priv, &session->skcb, + false, false); + if (IS_ERR(skb)) + return PTR_ERR(skb); + + skb_put_data(skb, dat, len); + if (j1939_tp_padding && len < 8) + memset(skb_put(skb, 8 - len), 0xff, 8 - len); + + return j1939_send_one(priv, skb); +} + +static int j1939_xtp_do_tx_ctl(struct j1939_priv *priv, + const struct j1939_sk_buff_cb *re_skcb, + bool swap_src_dst, pgn_t pgn, const u8 *dat) +{ + struct sk_buff *skb; + u8 *skdat; + + if (!j1939_tp_im_involved(re_skcb, swap_src_dst)) + return 0; + + skb = j1939_tp_tx_dat_new(priv, re_skcb, true, swap_src_dst); + if (IS_ERR(skb)) + return PTR_ERR(skb); + + skdat = skb_put(skb, 8); + memcpy(skdat, dat, 5); + skdat[5] = (pgn >> 0); + skdat[6] = (pgn >> 8); + skdat[7] = (pgn >> 16); + + return j1939_send_one(priv, skb); +} + +static inline int j1939_tp_tx_ctl(struct j1939_session *session, + bool swap_src_dst, const u8 *dat) +{ + struct j1939_priv *priv = session->priv; + + return j1939_xtp_do_tx_ctl(priv, &session->skcb, + swap_src_dst, + session->skcb.addr.pgn, dat); +} + +static int j1939_xtp_tx_abort(struct j1939_priv *priv, + const struct j1939_sk_buff_cb *re_skcb, + bool swap_src_dst, + enum j1939_xtp_abort err, + pgn_t pgn) +{ + u8 dat[5]; + + if (!j1939_tp_im_involved(re_skcb, swap_src_dst)) + return 0; + + memset(dat, 0xff, sizeof(dat)); + dat[0] = J1939_TP_CMD_ABORT; + dat[1] = err; + return j1939_xtp_do_tx_ctl(priv, re_skcb, swap_src_dst, pgn, dat); +} + +void j1939_tp_schedule_txtimer(struct j1939_session *session, int msec) +{ + j1939_session_get(session); + hrtimer_start(&session->txtimer, ms_to_ktime(msec), + HRTIMER_MODE_REL_SOFT); +} + +static inline void j1939_tp_set_rxtimeout(struct j1939_session *session, + int msec) +{ + j1939_session_rxtimer_cancel(session); + j1939_session_get(session); + hrtimer_start(&session->rxtimer, ms_to_ktime(msec), + HRTIMER_MODE_REL_SOFT); +} + +static int j1939_session_tx_rts(struct j1939_session *session) +{ + u8 dat[8]; + int ret; + + memset(dat, 0xff, sizeof(dat)); + + dat[1] = (session->total_message_size >> 0); + dat[2] = (session->total_message_size >> 8); + dat[3] = session->pkt.total; + + if (session->skcb.addr.type == J1939_ETP) { + dat[0] = J1939_ETP_CMD_RTS; + dat[1] = (session->total_message_size >> 0); + dat[2] = (session->total_message_size >> 8); + dat[3] = (session->total_message_size >> 16); + dat[4] = (session->total_message_size >> 24); + } else if (j1939_cb_is_broadcast(&session->skcb)) { + dat[0] = J1939_TP_CMD_BAM; + /* fake cts for broadcast */ + session->pkt.tx = 0; + } else { + dat[0] = J1939_TP_CMD_RTS; + dat[4] = dat[3]; + } + + if (dat[0] == session->last_txcmd) + /* done already */ + return 0; + + ret = j1939_tp_tx_ctl(session, false, dat); + if (ret < 0) + return ret; + + session->last_txcmd = dat[0]; + if (dat[0] == J1939_TP_CMD_BAM) + j1939_tp_schedule_txtimer(session, 50); + + j1939_tp_set_rxtimeout(session, 1250); + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + return 0; +} + +static int j1939_session_tx_dpo(struct j1939_session *session) +{ + unsigned int pkt; + u8 dat[8]; + int ret; + + memset(dat, 0xff, sizeof(dat)); + + dat[0] = J1939_ETP_CMD_DPO; + session->pkt.dpo = session->pkt.tx_acked; + pkt = session->pkt.dpo; + dat[1] = session->pkt.last - session->pkt.tx_acked; + dat[2] = (pkt >> 0); + dat[3] = (pkt >> 8); + dat[4] = (pkt >> 16); + + ret = j1939_tp_tx_ctl(session, false, dat); + if (ret < 0) + return ret; + + session->last_txcmd = dat[0]; + j1939_tp_set_rxtimeout(session, 1250); + session->pkt.tx = session->pkt.tx_acked; + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + return 0; +} + +static int j1939_session_tx_dat(struct j1939_session *session) +{ + struct j1939_priv *priv = session->priv; + struct j1939_sk_buff_cb *skcb; + int offset, pkt_done, pkt_end; + unsigned int len, pdelay; + struct sk_buff *se_skb; + const u8 *tpdat; + int ret = 0; + u8 dat[8]; + + se_skb = j1939_session_skb_find(session); + if (!se_skb) + return -ENOBUFS; + + skcb = j1939_skb_to_cb(se_skb); + tpdat = se_skb->data; + ret = 0; + pkt_done = 0; + if (session->skcb.addr.type != J1939_ETP && + j1939_cb_is_broadcast(&session->skcb)) + pkt_end = session->pkt.total; + else + pkt_end = session->pkt.last; + + while (session->pkt.tx < pkt_end) { + dat[0] = session->pkt.tx - session->pkt.dpo + 1; + offset = (session->pkt.tx * 7) - skcb->offset; + len = se_skb->len - offset; + if (len > 7) + len = 7; + + memcpy(&dat[1], &tpdat[offset], len); + ret = j1939_tp_tx_dat(session, dat, len + 1); + if (ret < 0) { + /* ENOBUS == CAN interface TX queue is full */ + if (ret != -ENOBUFS) + netdev_alert(priv->ndev, + "%s: 0x%p: queue data error: %i\n", + __func__, session, ret); + break; + } + + session->last_txcmd = 0xff; + pkt_done++; + session->pkt.tx++; + pdelay = j1939_cb_is_broadcast(&session->skcb) ? 50 : + j1939_tp_packet_delay; + + if (session->pkt.tx < session->pkt.total && pdelay) { + j1939_tp_schedule_txtimer(session, pdelay); + break; + } + } + + if (pkt_done) + j1939_tp_set_rxtimeout(session, 250); + + return ret; +} + +static int j1939_xtp_txnext_transmiter(struct j1939_session *session) +{ + struct j1939_priv *priv = session->priv; + int ret = 0; + + if (!j1939_tp_im_transmitter(&session->skcb)) { + netdev_alert(priv->ndev, "%s: 0x%p: called by not transmitter!\n", + __func__, session); + return -EINVAL; + } + + switch (session->last_cmd) { + case 0: + ret = j1939_session_tx_rts(session); + break; + + case J1939_ETP_CMD_CTS: + if (session->last_txcmd != J1939_ETP_CMD_DPO) { + ret = j1939_session_tx_dpo(session); + if (ret) + return ret; + } + + /* fall through */ + case J1939_TP_CMD_CTS: + case 0xff: /* did some data */ + case J1939_ETP_CMD_DPO: + case J1939_TP_CMD_BAM: + ret = j1939_session_tx_dat(session); + + break; + default: + netdev_alert(priv->ndev, "%s: 0x%p: unexpected last_cmd: %x\n", + __func__, session, session->last_cmd); + } + + return ret; +} + +static int j1939_session_tx_cts(struct j1939_session *session) +{ + struct j1939_priv *priv = session->priv; + unsigned int pkt, len; + int ret; + u8 dat[8]; + + if (!j1939_sk_recv_match(priv, &session->skcb)) + return -ENOENT; + + len = session->pkt.total - session->pkt.rx; + len = min3(len, session->pkt.block, j1939_tp_block ?: 255); + memset(dat, 0xff, sizeof(dat)); + + if (session->skcb.addr.type == J1939_ETP) { + pkt = session->pkt.rx + 1; + dat[0] = J1939_ETP_CMD_CTS; + dat[1] = len; + dat[2] = (pkt >> 0); + dat[3] = (pkt >> 8); + dat[4] = (pkt >> 16); + } else { + dat[0] = J1939_TP_CMD_CTS; + dat[1] = len; + dat[2] = session->pkt.rx + 1; + } + + if (dat[0] == session->last_txcmd) + /* done already */ + return 0; + + ret = j1939_tp_tx_ctl(session, true, dat); + if (ret < 0) + return ret; + + if (len) + /* only mark cts done when len is set */ + session->last_txcmd = dat[0]; + j1939_tp_set_rxtimeout(session, 1250); + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + return 0; +} + +static int j1939_session_tx_eoma(struct j1939_session *session) +{ + struct j1939_priv *priv = session->priv; + u8 dat[8]; + int ret; + + if (!j1939_sk_recv_match(priv, &session->skcb)) + return -ENOENT; + + memset(dat, 0xff, sizeof(dat)); + + if (session->skcb.addr.type == J1939_ETP) { + dat[0] = J1939_ETP_CMD_EOMA; + dat[1] = session->total_message_size >> 0; + dat[2] = session->total_message_size >> 8; + dat[3] = session->total_message_size >> 16; + dat[4] = session->total_message_size >> 24; + } else { + dat[0] = J1939_TP_CMD_EOMA; + dat[1] = session->total_message_size; + dat[2] = session->total_message_size >> 8; + dat[3] = session->pkt.total; + } + + if (dat[0] == session->last_txcmd) + /* done already */ + return 0; + + ret = j1939_tp_tx_ctl(session, true, dat); + if (ret < 0) + return ret; + + session->last_txcmd = dat[0]; + + /* wait for the EOMA packet to come in */ + j1939_tp_set_rxtimeout(session, 1250); + + netdev_dbg(session->priv->ndev, "%p: 0x%p\n", __func__, session); + + return 0; +} + +static int j1939_xtp_txnext_receiver(struct j1939_session *session) +{ + struct j1939_priv *priv = session->priv; + int ret = 0; + + if (!j1939_tp_im_receiver(&session->skcb)) { + netdev_alert(priv->ndev, "%s: 0x%p: called by not receiver!\n", + __func__, session); + return -EINVAL; + } + + switch (session->last_cmd) { + case J1939_TP_CMD_RTS: + case J1939_ETP_CMD_RTS: + ret = j1939_session_tx_cts(session); + break; + + case J1939_ETP_CMD_CTS: + case J1939_TP_CMD_CTS: + case 0xff: /* did some data */ + case J1939_ETP_CMD_DPO: + if ((session->skcb.addr.type == J1939_TP && + j1939_cb_is_broadcast(&session->skcb))) + break; + + if (session->pkt.rx >= session->pkt.total) { + ret = j1939_session_tx_eoma(session); + } else if (session->pkt.rx >= session->pkt.last) { + session->last_txcmd = 0; + ret = j1939_session_tx_cts(session); + } + break; + default: + netdev_alert(priv->ndev, "%s: 0x%p: unexpected last_cmd: %x\n", + __func__, session, session->last_cmd); + } + + return ret; +} + +static int j1939_simple_txnext(struct j1939_session *session) +{ + struct j1939_priv *priv = session->priv; + struct sk_buff *se_skb = j1939_session_skb_find(session); + struct sk_buff *skb; + int ret; + + if (!se_skb) + return 0; + + skb = skb_clone(se_skb, GFP_ATOMIC); + if (!skb) + return -ENOMEM; + + can_skb_set_owner(skb, se_skb->sk); + + j1939_tp_set_rxtimeout(session, J1939_SIMPLE_ECHO_TIMEOUT_MS); + + ret = j1939_send_one(priv, skb); + if (ret) + return ret; + + j1939_sk_errqueue(session, J1939_ERRQUEUE_SCHED); + j1939_sk_queue_activate_next(session); + + return 0; +} + +static bool j1939_session_deactivate_locked(struct j1939_session *session) +{ + bool active = false; + + lockdep_assert_held(&session->priv->active_session_list_lock); + + if (session->state >= J1939_SESSION_ACTIVE && + session->state < J1939_SESSION_ACTIVE_MAX) { + active = true; + + list_del_init(&session->active_session_list_entry); + session->state = J1939_SESSION_DONE; + j1939_session_put(session); + } + + return active; +} + +static bool j1939_session_deactivate(struct j1939_session *session) +{ + bool active; + + j1939_session_list_lock(session->priv); + active = j1939_session_deactivate_locked(session); + j1939_session_list_unlock(session->priv); + + return active; +} + +static void +j1939_session_deactivate_activate_next(struct j1939_session *session) +{ + if (j1939_session_deactivate(session)) + j1939_sk_queue_activate_next(session); +} + +static void j1939_session_cancel(struct j1939_session *session, + enum j1939_xtp_abort err) +{ + struct j1939_priv *priv = session->priv; + + WARN_ON_ONCE(!err); + + session->err = j1939_xtp_abort_to_errno(priv, err); + /* do not send aborts on incoming broadcasts */ + if (!j1939_cb_is_broadcast(&session->skcb)) { + session->state = J1939_SESSION_WAITING_ABORT; + j1939_xtp_tx_abort(priv, &session->skcb, + !session->transmission, + err, session->skcb.addr.pgn); + } + + if (session->sk) + j1939_sk_send_loop_abort(session->sk, session->err); +} + +static enum hrtimer_restart j1939_tp_txtimer(struct hrtimer *hrtimer) +{ + struct j1939_session *session = + container_of(hrtimer, struct j1939_session, txtimer); + struct j1939_priv *priv = session->priv; + int ret = 0; + + if (session->skcb.addr.type == J1939_SIMPLE) { + ret = j1939_simple_txnext(session); + } else { + if (session->transmission) + ret = j1939_xtp_txnext_transmiter(session); + else + ret = j1939_xtp_txnext_receiver(session); + } + + switch (ret) { + case -ENOBUFS: + /* Retry limit is currently arbitrary chosen */ + if (session->tx_retry < J1939_XTP_TX_RETRY_LIMIT) { + session->tx_retry++; + j1939_tp_schedule_txtimer(session, + 10 + prandom_u32_max(16)); + } else { + netdev_alert(priv->ndev, "%s: 0x%p: tx retry count reached\n", + __func__, session); + session->err = -ENETUNREACH; + j1939_session_rxtimer_cancel(session); + j1939_session_deactivate_activate_next(session); + } + break; + case -ENETDOWN: + /* In this case we should get a netdev_event(), all active + * sessions will be cleared by + * j1939_cancel_all_active_sessions(). So handle this as an + * error, but let j1939_cancel_all_active_sessions() do the + * cleanup including propagation of the error to user space. + */ + break; + case 0: + session->tx_retry = 0; + break; + default: + netdev_alert(priv->ndev, "%s: 0x%p: tx aborted with unknown reason: %i\n", + __func__, session, ret); + if (session->skcb.addr.type != J1939_SIMPLE) { + j1939_tp_set_rxtimeout(session, + J1939_XTP_ABORT_TIMEOUT_MS); + j1939_session_cancel(session, J1939_XTP_ABORT_OTHER); + } else { + session->err = ret; + j1939_session_rxtimer_cancel(session); + j1939_session_deactivate_activate_next(session); + } + } + + j1939_session_put(session); + + return HRTIMER_NORESTART; +} + +static void j1939_session_completed(struct j1939_session *session) +{ + struct sk_buff *skb; + + if (!session->transmission) { + skb = j1939_session_skb_find(session); + /* distribute among j1939 receivers */ + j1939_sk_recv(session->priv, skb); + } + + j1939_session_deactivate_activate_next(session); +} + +static enum hrtimer_restart j1939_tp_rxtimer(struct hrtimer *hrtimer) +{ + struct j1939_session *session = container_of(hrtimer, + struct j1939_session, + rxtimer); + struct j1939_priv *priv = session->priv; + + if (session->state == J1939_SESSION_WAITING_ABORT) { + netdev_alert(priv->ndev, "%s: 0x%p: abort rx timeout. Force session deactivation\n", + __func__, session); + + j1939_session_deactivate_activate_next(session); + + } else if (session->skcb.addr.type == J1939_SIMPLE) { + netdev_alert(priv->ndev, "%s: 0x%p: Timeout. Failed to send simple message.\n", + __func__, session); + + /* The message is probably stuck in the CAN controller and can + * be send as soon as CAN bus is in working state again. + */ + session->err = -ETIME; + j1939_session_deactivate(session); + } else { + netdev_alert(priv->ndev, "%s: 0x%p: rx timeout, send abort\n", + __func__, session); + + j1939_session_list_lock(session->priv); + if (session->state >= J1939_SESSION_ACTIVE && + session->state < J1939_SESSION_ACTIVE_MAX) { + j1939_session_get(session); + hrtimer_start(&session->rxtimer, + ms_to_ktime(J1939_XTP_ABORT_TIMEOUT_MS), + HRTIMER_MODE_REL_SOFT); + j1939_session_cancel(session, J1939_XTP_ABORT_TIMEOUT); + } + j1939_session_list_unlock(session->priv); + } + + j1939_session_put(session); + + return HRTIMER_NORESTART; +} + +static bool j1939_xtp_rx_cmd_bad_pgn(struct j1939_session *session, + const struct sk_buff *skb) +{ + const struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + pgn_t pgn = j1939_xtp_ctl_to_pgn(skb->data); + struct j1939_priv *priv = session->priv; + enum j1939_xtp_abort abort = J1939_XTP_NO_ABORT; + u8 cmd = skb->data[0]; + + if (session->skcb.addr.pgn == pgn) + return false; + + switch (cmd) { + case J1939_TP_CMD_BAM: + abort = J1939_XTP_NO_ABORT; + break; + + case J1939_ETP_CMD_RTS: + case J1939_TP_CMD_RTS: /* fall through */ + abort = J1939_XTP_ABORT_BUSY; + break; + + case J1939_ETP_CMD_CTS: + case J1939_TP_CMD_CTS: /* fall through */ + abort = J1939_XTP_ABORT_ECTS_UNXPECTED_PGN; + break; + + case J1939_ETP_CMD_DPO: + abort = J1939_XTP_ABORT_BAD_EDPO_PGN; + break; + + case J1939_ETP_CMD_EOMA: + case J1939_TP_CMD_EOMA: /* fall through */ + abort = J1939_XTP_ABORT_OTHER; + break; + + case J1939_ETP_CMD_ABORT: /* && J1939_TP_CMD_ABORT */ + abort = J1939_XTP_NO_ABORT; + break; + + default: + WARN_ON_ONCE(1); + break; + } + + netdev_warn(priv->ndev, "%s: 0x%p: CMD 0x%02x with PGN 0x%05x for running session with different PGN 0x%05x.\n", + __func__, session, cmd, pgn, session->skcb.addr.pgn); + if (abort != J1939_XTP_NO_ABORT) + j1939_xtp_tx_abort(priv, skcb, true, abort, pgn); + + return true; +} + +static void j1939_xtp_rx_abort_one(struct j1939_priv *priv, struct sk_buff *skb, + bool reverse, bool transmitter) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_session *session; + u8 abort = skb->data[1]; + + session = j1939_session_get_by_addr(priv, &skcb->addr, reverse, + transmitter); + if (!session) + return; + + if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) + goto abort_put; + + netdev_info(priv->ndev, "%s: 0x%p: 0x%05x: (%u) %s\n", __func__, + session, j1939_xtp_ctl_to_pgn(skb->data), abort, + j1939_xtp_abort_to_str(abort)); + + j1939_session_timers_cancel(session); + session->err = j1939_xtp_abort_to_errno(priv, abort); + if (session->sk) + j1939_sk_send_loop_abort(session->sk, session->err); + j1939_session_deactivate_activate_next(session); + +abort_put: + j1939_session_put(session); +} + +/* abort packets may come in 2 directions */ +static void +j1939_xtp_rx_abort(struct j1939_priv *priv, struct sk_buff *skb, + bool transmitter) +{ + j1939_xtp_rx_abort_one(priv, skb, false, transmitter); + j1939_xtp_rx_abort_one(priv, skb, true, transmitter); +} + +static void +j1939_xtp_rx_eoma_one(struct j1939_session *session, struct sk_buff *skb) +{ + if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) + return; + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + session->pkt.tx_acked = session->pkt.total; + j1939_session_timers_cancel(session); + /* transmitted without problems */ + j1939_session_completed(session); +} + +static void +j1939_xtp_rx_eoma(struct j1939_priv *priv, struct sk_buff *skb, + bool transmitter) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_session *session; + + session = j1939_session_get_by_addr(priv, &skcb->addr, true, + transmitter); + if (!session) + return; + + j1939_xtp_rx_eoma_one(session, skb); + j1939_session_put(session); +} + +static void +j1939_xtp_rx_cts_one(struct j1939_session *session, struct sk_buff *skb) +{ + enum j1939_xtp_abort err = J1939_XTP_ABORT_FAULT; + unsigned int pkt; + const u8 *dat; + + dat = skb->data; + + if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) + return; + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + if (session->last_cmd == dat[0]) { + err = J1939_XTP_ABORT_DUP_SEQ; + goto out_session_cancel; + } + + if (session->skcb.addr.type == J1939_ETP) + pkt = j1939_etp_ctl_to_packet(dat); + else + pkt = dat[2]; + + if (!pkt) + goto out_session_cancel; + else if (dat[1] > session->pkt.block /* 0xff for etp */) + goto out_session_cancel; + + /* set packet counters only when not CTS(0) */ + session->pkt.tx_acked = pkt - 1; + j1939_session_skb_drop_old(session); + session->pkt.last = session->pkt.tx_acked + dat[1]; + if (session->pkt.last > session->pkt.total) + /* safety measure */ + session->pkt.last = session->pkt.total; + /* TODO: do not set tx here, do it in txtimer */ + session->pkt.tx = session->pkt.tx_acked; + + session->last_cmd = dat[0]; + if (dat[1]) { + j1939_tp_set_rxtimeout(session, 1250); + if (session->transmission) { + if (session->pkt.tx_acked) + j1939_sk_errqueue(session, + J1939_ERRQUEUE_SCHED); + j1939_session_txtimer_cancel(session); + j1939_tp_schedule_txtimer(session, 0); + } + } else { + /* CTS(0) */ + j1939_tp_set_rxtimeout(session, 550); + } + return; + + out_session_cancel: + j1939_session_timers_cancel(session); + j1939_tp_set_rxtimeout(session, J1939_XTP_ABORT_TIMEOUT_MS); + j1939_session_cancel(session, err); +} + +static void +j1939_xtp_rx_cts(struct j1939_priv *priv, struct sk_buff *skb, bool transmitter) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_session *session; + + session = j1939_session_get_by_addr(priv, &skcb->addr, true, + transmitter); + if (!session) + return; + j1939_xtp_rx_cts_one(session, skb); + j1939_session_put(session); +} + +static struct j1939_session *j1939_session_new(struct j1939_priv *priv, + struct sk_buff *skb, size_t size) +{ + struct j1939_session *session; + struct j1939_sk_buff_cb *skcb; + + session = kzalloc(sizeof(*session), gfp_any()); + if (!session) + return NULL; + + INIT_LIST_HEAD(&session->active_session_list_entry); + INIT_LIST_HEAD(&session->sk_session_queue_entry); + kref_init(&session->kref); + + j1939_priv_get(priv); + session->priv = priv; + session->total_message_size = size; + session->state = J1939_SESSION_NEW; + + skb_queue_head_init(&session->skb_queue); + skb_queue_tail(&session->skb_queue, skb); + + skcb = j1939_skb_to_cb(skb); + memcpy(&session->skcb, skcb, sizeof(session->skcb)); + + hrtimer_init(&session->txtimer, CLOCK_MONOTONIC, + HRTIMER_MODE_REL_SOFT); + session->txtimer.function = j1939_tp_txtimer; + hrtimer_init(&session->rxtimer, CLOCK_MONOTONIC, + HRTIMER_MODE_REL_SOFT); + session->rxtimer.function = j1939_tp_rxtimer; + + netdev_dbg(priv->ndev, "%s: 0x%p: sa: %02x, da: %02x\n", + __func__, session, skcb->addr.sa, skcb->addr.da); + + return session; +} + +static struct +j1939_session *j1939_session_fresh_new(struct j1939_priv *priv, + int size, + const struct j1939_sk_buff_cb *rel_skcb) +{ + struct sk_buff *skb; + struct j1939_sk_buff_cb *skcb; + struct j1939_session *session; + + skb = alloc_skb(size + sizeof(struct can_skb_priv), GFP_ATOMIC); + if (unlikely(!skb)) + return NULL; + + skb->dev = priv->ndev; + can_skb_reserve(skb); + can_skb_prv(skb)->ifindex = priv->ndev->ifindex; + skcb = j1939_skb_to_cb(skb); + memcpy(skcb, rel_skcb, sizeof(*skcb)); + + session = j1939_session_new(priv, skb, skb->len); + if (!session) { + kfree_skb(skb); + return NULL; + } + + /* alloc data area */ + skb_put(skb, size); + /* skb is recounted in j1939_session_new() */ + return session; +} + +int j1939_session_activate(struct j1939_session *session) +{ + struct j1939_priv *priv = session->priv; + struct j1939_session *active = NULL; + int ret = 0; + + j1939_session_list_lock(priv); + if (session->skcb.addr.type != J1939_SIMPLE) + active = j1939_session_get_by_addr_locked(priv, + &priv->active_session_list, + &session->skcb.addr, false, + session->transmission); + if (active) { + j1939_session_put(active); + ret = -EAGAIN; + } else { + WARN_ON_ONCE(session->state != J1939_SESSION_NEW); + list_add_tail(&session->active_session_list_entry, + &priv->active_session_list); + j1939_session_get(session); + session->state = J1939_SESSION_ACTIVE; + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", + __func__, session); + } + j1939_session_list_unlock(priv); + + return ret; +} + +static struct +j1939_session *j1939_xtp_rx_rts_session_new(struct j1939_priv *priv, + struct sk_buff *skb) +{ + enum j1939_xtp_abort abort = J1939_XTP_NO_ABORT; + struct j1939_sk_buff_cb skcb = *j1939_skb_to_cb(skb); + struct j1939_session *session; + const u8 *dat; + pgn_t pgn; + int len; + + netdev_dbg(priv->ndev, "%s\n", __func__); + + dat = skb->data; + pgn = j1939_xtp_ctl_to_pgn(dat); + skcb.addr.pgn = pgn; + + if (!j1939_sk_recv_match(priv, &skcb)) + return NULL; + + if (skcb.addr.type == J1939_ETP) { + len = j1939_etp_ctl_to_size(dat); + if (len > J1939_MAX_ETP_PACKET_SIZE) + abort = J1939_XTP_ABORT_FAULT; + else if (len > priv->tp_max_packet_size) + abort = J1939_XTP_ABORT_RESOURCE; + else if (len <= J1939_MAX_TP_PACKET_SIZE) + abort = J1939_XTP_ABORT_FAULT; + } else { + len = j1939_tp_ctl_to_size(dat); + if (len > J1939_MAX_TP_PACKET_SIZE) + abort = J1939_XTP_ABORT_FAULT; + else if (len > priv->tp_max_packet_size) + abort = J1939_XTP_ABORT_RESOURCE; + } + + if (abort != J1939_XTP_NO_ABORT) { + j1939_xtp_tx_abort(priv, &skcb, true, abort, pgn); + return NULL; + } + + session = j1939_session_fresh_new(priv, len, &skcb); + if (!session) { + j1939_xtp_tx_abort(priv, &skcb, true, + J1939_XTP_ABORT_RESOURCE, pgn); + return NULL; + } + + /* initialize the control buffer: plain copy */ + session->pkt.total = (len + 6) / 7; + session->pkt.block = 0xff; + if (skcb.addr.type != J1939_ETP) { + if (dat[3] != session->pkt.total) + netdev_alert(priv->ndev, "%s: 0x%p: strange total, %u != %u\n", + __func__, session, session->pkt.total, + dat[3]); + session->pkt.total = dat[3]; + session->pkt.block = min(dat[3], dat[4]); + } + + session->pkt.rx = 0; + session->pkt.tx = 0; + + WARN_ON_ONCE(j1939_session_activate(session)); + + return session; +} + +static int j1939_xtp_rx_rts_session_active(struct j1939_session *session, + struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_priv *priv = session->priv; + + if (!session->transmission) { + if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) + return -EBUSY; + + /* RTS on active session */ + j1939_session_timers_cancel(session); + j1939_tp_set_rxtimeout(session, J1939_XTP_ABORT_TIMEOUT_MS); + j1939_session_cancel(session, J1939_XTP_ABORT_BUSY); + } + + if (session->last_cmd != 0) { + /* we received a second rts on the same connection */ + netdev_alert(priv->ndev, "%s: 0x%p: connection exists (%02x %02x). last cmd: %x\n", + __func__, session, skcb->addr.sa, skcb->addr.da, + session->last_cmd); + + j1939_session_timers_cancel(session); + j1939_tp_set_rxtimeout(session, J1939_XTP_ABORT_TIMEOUT_MS); + j1939_session_cancel(session, J1939_XTP_ABORT_BUSY); + + return -EBUSY; + } + + if (session->skcb.addr.sa != skcb->addr.sa || + session->skcb.addr.da != skcb->addr.da) + netdev_warn(priv->ndev, "%s: 0x%p: session->skcb.addr.sa=0x%02x skcb->addr.sa=0x%02x session->skcb.addr.da=0x%02x skcb->addr.da=0x%02x\n", + __func__, session, + session->skcb.addr.sa, skcb->addr.sa, + session->skcb.addr.da, skcb->addr.da); + /* make sure 'sa' & 'da' are correct ! + * They may be 'not filled in yet' for sending + * skb's, since they did not pass the Address Claim ever. + */ + session->skcb.addr.sa = skcb->addr.sa; + session->skcb.addr.da = skcb->addr.da; + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + return 0; +} + +static void j1939_xtp_rx_rts(struct j1939_priv *priv, struct sk_buff *skb, + bool transmitter) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_session *session; + u8 cmd = skb->data[0]; + + session = j1939_session_get_by_addr(priv, &skcb->addr, false, + transmitter); + + if (!session) { + if (transmitter) { + /* If we're the transmitter and this function is called, + * we received our own RTS. A session has already been + * created. + * + * For some reasons however it might have been destroyed + * already. So don't create a new one here (using + * "j1939_xtp_rx_rts_session_new()") as this will be a + * receiver session. + * + * The reasons the session is already destroyed might + * be: + * - user space closed socket was and the session was + * aborted + * - session was aborted due to external abort message + */ + return; + } + session = j1939_xtp_rx_rts_session_new(priv, skb); + if (!session) + return; + } else { + if (j1939_xtp_rx_rts_session_active(session, skb)) { + j1939_session_put(session); + return; + } + } + session->last_cmd = cmd; + + j1939_tp_set_rxtimeout(session, 1250); + + if (cmd != J1939_TP_CMD_BAM && !session->transmission) { + j1939_session_txtimer_cancel(session); + j1939_tp_schedule_txtimer(session, 0); + } + + j1939_session_put(session); +} + +static void j1939_xtp_rx_dpo_one(struct j1939_session *session, + struct sk_buff *skb) +{ + const u8 *dat = skb->data; + + if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) + return; + + netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); + + /* transmitted without problems */ + session->pkt.dpo = j1939_etp_ctl_to_packet(skb->data); + session->last_cmd = dat[0]; + j1939_tp_set_rxtimeout(session, 750); +} + +static void j1939_xtp_rx_dpo(struct j1939_priv *priv, struct sk_buff *skb, + bool transmitter) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_session *session; + + session = j1939_session_get_by_addr(priv, &skcb->addr, false, + transmitter); + if (!session) { + netdev_info(priv->ndev, + "%s: no connection found\n", __func__); + return; + } + + j1939_xtp_rx_dpo_one(session, skb); + j1939_session_put(session); +} + +static void j1939_xtp_rx_dat_one(struct j1939_session *session, + struct sk_buff *skb) +{ + struct j1939_priv *priv = session->priv; + struct j1939_sk_buff_cb *skcb; + struct sk_buff *se_skb; + const u8 *dat; + u8 *tpdat; + int offset; + int nbytes; + bool final = false; + bool do_cts_eoma = false; + int packet; + + skcb = j1939_skb_to_cb(skb); + dat = skb->data; + if (skb->len <= 1) + /* makes no sense */ + goto out_session_cancel; + + switch (session->last_cmd) { + case 0xff: + break; + case J1939_ETP_CMD_DPO: + if (skcb->addr.type == J1939_ETP) + break; + /* fall through */ + case J1939_TP_CMD_BAM: /* fall through */ + case J1939_TP_CMD_CTS: /* fall through */ + if (skcb->addr.type != J1939_ETP) + break; + /* fall through */ + default: + netdev_info(priv->ndev, "%s: 0x%p: last %02x\n", __func__, + session, session->last_cmd); + goto out_session_cancel; + } + + packet = (dat[0] - 1 + session->pkt.dpo); + if (packet > session->pkt.total || + (session->pkt.rx + 1) > session->pkt.total) { + netdev_info(priv->ndev, "%s: 0x%p: should have been completed\n", + __func__, session); + goto out_session_cancel; + } + se_skb = j1939_session_skb_find(session); + if (!se_skb) { + netdev_warn(priv->ndev, "%s: 0x%p: no skb found\n", __func__, + session); + goto out_session_cancel; + } + + skcb = j1939_skb_to_cb(se_skb); + offset = packet * 7 - skcb->offset; + nbytes = se_skb->len - offset; + if (nbytes > 7) + nbytes = 7; + if (nbytes <= 0 || (nbytes + 1) > skb->len) { + netdev_info(priv->ndev, "%s: 0x%p: nbytes %i, len %i\n", + __func__, session, nbytes, skb->len); + goto out_session_cancel; + } + + tpdat = se_skb->data; + memcpy(&tpdat[offset], &dat[1], nbytes); + if (packet == session->pkt.rx) + session->pkt.rx++; + + if (skcb->addr.type != J1939_ETP && + j1939_cb_is_broadcast(&session->skcb)) { + if (session->pkt.rx >= session->pkt.total) + final = true; + } else { + /* never final, an EOMA must follow */ + if (session->pkt.rx >= session->pkt.last) + do_cts_eoma = true; + } + + if (final) { + j1939_session_completed(session); + } else if (do_cts_eoma) { + j1939_tp_set_rxtimeout(session, 1250); + if (!session->transmission) + j1939_tp_schedule_txtimer(session, 0); + } else { + j1939_tp_set_rxtimeout(session, 250); + } + session->last_cmd = 0xff; + j1939_session_put(session); + + return; + + out_session_cancel: + j1939_session_timers_cancel(session); + j1939_tp_set_rxtimeout(session, J1939_XTP_ABORT_TIMEOUT_MS); + j1939_session_cancel(session, J1939_XTP_ABORT_FAULT); + j1939_session_put(session); +} + +static void j1939_xtp_rx_dat(struct j1939_priv *priv, struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb; + struct j1939_session *session; + + skcb = j1939_skb_to_cb(skb); + + if (j1939_tp_im_transmitter(skcb)) { + session = j1939_session_get_by_addr(priv, &skcb->addr, false, + true); + if (!session) + netdev_info(priv->ndev, "%s: no tx connection found\n", + __func__); + else + j1939_xtp_rx_dat_one(session, skb); + } + + if (j1939_tp_im_receiver(skcb)) { + session = j1939_session_get_by_addr(priv, &skcb->addr, false, + false); + if (!session) + netdev_info(priv->ndev, "%s: no rx connection found\n", + __func__); + else + j1939_xtp_rx_dat_one(session, skb); + } +} + +/* j1939 main intf */ +struct j1939_session *j1939_tp_send(struct j1939_priv *priv, + struct sk_buff *skb, size_t size) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + struct j1939_session *session; + int ret; + + if (skcb->addr.pgn == J1939_TP_PGN_DAT || + skcb->addr.pgn == J1939_TP_PGN_CTL || + skcb->addr.pgn == J1939_ETP_PGN_DAT || + skcb->addr.pgn == J1939_ETP_PGN_CTL) + /* avoid conflict */ + return ERR_PTR(-EDOM); + + if (size > priv->tp_max_packet_size) + return ERR_PTR(-EMSGSIZE); + + if (size <= 8) + skcb->addr.type = J1939_SIMPLE; + else if (size > J1939_MAX_TP_PACKET_SIZE) + skcb->addr.type = J1939_ETP; + else + skcb->addr.type = J1939_TP; + + if (skcb->addr.type == J1939_ETP && + j1939_cb_is_broadcast(skcb)) + return ERR_PTR(-EDESTADDRREQ); + + /* fill in addresses from names */ + ret = j1939_ac_fixup(priv, skb); + if (unlikely(ret)) + return ERR_PTR(ret); + + /* fix DST flags, it may be used there soon */ + if (j1939_address_is_unicast(skcb->addr.da) && + priv->ents[skcb->addr.da].nusers) + skcb->flags |= J1939_ECU_LOCAL_DST; + + /* src is always local, I'm sending ... */ + skcb->flags |= J1939_ECU_LOCAL_SRC; + + /* prepare new session */ + session = j1939_session_new(priv, skb, size); + if (!session) + return ERR_PTR(-ENOMEM); + + /* skb is recounted in j1939_session_new() */ + session->sk = skb->sk; + session->transmission = true; + session->pkt.total = (size + 6) / 7; + session->pkt.block = skcb->addr.type == J1939_ETP ? 255 : + min(j1939_tp_block ?: 255, session->pkt.total); + + if (j1939_cb_is_broadcast(&session->skcb)) + /* set the end-packet for broadcast */ + session->pkt.last = session->pkt.total; + + skcb->tskey = session->sk->sk_tskey++; + session->tskey = skcb->tskey; + + return session; +} + +static void j1939_tp_cmd_recv(struct j1939_priv *priv, struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + int extd = J1939_TP; + u8 cmd = skb->data[0]; + + switch (cmd) { + case J1939_ETP_CMD_RTS: + extd = J1939_ETP; + /* fall through */ + case J1939_TP_CMD_BAM: /* fall through */ + case J1939_TP_CMD_RTS: /* fall through */ + if (skcb->addr.type != extd) + return; + + if (cmd == J1939_TP_CMD_RTS && j1939_cb_is_broadcast(skcb)) { + netdev_alert(priv->ndev, "%s: rts without destination (%02x)\n", + __func__, skcb->addr.sa); + return; + } + + if (j1939_tp_im_transmitter(skcb)) + j1939_xtp_rx_rts(priv, skb, true); + + if (j1939_tp_im_receiver(skcb)) + j1939_xtp_rx_rts(priv, skb, false); + + break; + + case J1939_ETP_CMD_CTS: + extd = J1939_ETP; + /* fall through */ + case J1939_TP_CMD_CTS: + if (skcb->addr.type != extd) + return; + + if (j1939_tp_im_transmitter(skcb)) + j1939_xtp_rx_cts(priv, skb, false); + + if (j1939_tp_im_receiver(skcb)) + j1939_xtp_rx_cts(priv, skb, true); + + break; + + case J1939_ETP_CMD_DPO: + if (skcb->addr.type != J1939_ETP) + return; + + if (j1939_tp_im_transmitter(skcb)) + j1939_xtp_rx_dpo(priv, skb, true); + + if (j1939_tp_im_receiver(skcb)) + j1939_xtp_rx_dpo(priv, skb, false); + + break; + + case J1939_ETP_CMD_EOMA: + extd = J1939_ETP; + /* fall through */ + case J1939_TP_CMD_EOMA: + if (skcb->addr.type != extd) + return; + + if (j1939_tp_im_transmitter(skcb)) + j1939_xtp_rx_eoma(priv, skb, false); + + if (j1939_tp_im_receiver(skcb)) + j1939_xtp_rx_eoma(priv, skb, true); + + break; + + case J1939_ETP_CMD_ABORT: /* && J1939_TP_CMD_ABORT */ + if (j1939_tp_im_transmitter(skcb)) + j1939_xtp_rx_abort(priv, skb, true); + + if (j1939_tp_im_receiver(skcb)) + j1939_xtp_rx_abort(priv, skb, false); + + break; + default: + return; + } +} + +int j1939_tp_recv(struct j1939_priv *priv, struct sk_buff *skb) +{ + struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); + + if (!j1939_tp_im_involved_anydir(skcb)) + return 0; + + switch (skcb->addr.pgn) { + case J1939_ETP_PGN_DAT: + skcb->addr.type = J1939_ETP; + /* fall through */ + case J1939_TP_PGN_DAT: + j1939_xtp_rx_dat(priv, skb); + break; + + case J1939_ETP_PGN_CTL: + skcb->addr.type = J1939_ETP; + /* fall through */ + case J1939_TP_PGN_CTL: + if (skb->len < 8) + return 0; /* Don't care. Nothing to extract here */ + + j1939_tp_cmd_recv(priv, skb); + break; + default: + return 0; /* no problem */ + } + return 1; /* "I processed the message" */ +} + +void j1939_simple_recv(struct j1939_priv *priv, struct sk_buff *skb) +{ + struct j1939_session *session; + + if (!skb->sk) + return; + + j1939_session_list_lock(priv); + session = j1939_session_get_simple(priv, skb); + j1939_session_list_unlock(priv); + if (!session) { + netdev_warn(priv->ndev, + "%s: Received already invalidated message\n", + __func__); + return; + } + + j1939_session_timers_cancel(session); + j1939_session_deactivate(session); + j1939_session_put(session); +} + +int j1939_cancel_active_session(struct j1939_priv *priv, struct sock *sk) +{ + struct j1939_session *session, *saved; + + netdev_dbg(priv->ndev, "%s, sk: %p\n", __func__, sk); + j1939_session_list_lock(priv); + list_for_each_entry_safe(session, saved, + &priv->active_session_list, + active_session_list_entry) { + if (!sk || sk == session->sk) { + j1939_session_timers_cancel(session); + session->err = ESHUTDOWN; + j1939_session_deactivate_locked(session); + } + } + j1939_session_list_unlock(priv); + return NOTIFY_DONE; +} + +void j1939_tp_init(struct j1939_priv *priv) +{ + spin_lock_init(&priv->active_session_list_lock); + INIT_LIST_HEAD(&priv->active_session_list); + priv->tp_max_packet_size = J1939_MAX_ETP_PACKET_SIZE; +} |