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author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-09-18 22:34:53 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-09-18 22:34:53 +0300 |
commit | 81160dda9a7aad13c04e78bb2cfd3c4630e3afab (patch) | |
tree | 4bf79ffa9fc7dc5e2915ff978778c3402c491113 /net/can/j1939/address-claim.c | |
parent | 8b53c76533aa4356602aea98f98a2f3b4051464c (diff) | |
parent | 1bab8d4c488be22d57f9dd09968c90a0ddc413bf (diff) | |
download | linux-81160dda9a7aad13c04e78bb2cfd3c4630e3afab.tar.xz |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:
1) Support IPV6 RA Captive Portal Identifier, from Maciej Żenczykowski.
2) Use bio_vec in the networking instead of custom skb_frag_t, from
Matthew Wilcox.
3) Make use of xmit_more in r8169 driver, from Heiner Kallweit.
4) Add devmap_hash to xdp, from Toke Høiland-Jørgensen.
5) Support all variants of 5750X bnxt_en chips, from Michael Chan.
6) More RTNL avoidance work in the core and mlx5 driver, from Vlad
Buslov.
7) Add TCP syn cookies bpf helper, from Petar Penkov.
8) Add 'nettest' to selftests and use it, from David Ahern.
9) Add extack support to drop_monitor, add packet alert mode and
support for HW drops, from Ido Schimmel.
10) Add VLAN offload to stmmac, from Jose Abreu.
11) Lots of devm_platform_ioremap_resource() conversions, from
YueHaibing.
12) Add IONIC driver, from Shannon Nelson.
13) Several kTLS cleanups, from Jakub Kicinski.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1930 commits)
mlxsw: spectrum_buffers: Add the ability to query the CPU port's shared buffer
mlxsw: spectrum: Register CPU port with devlink
mlxsw: spectrum_buffers: Prevent changing CPU port's configuration
net: ena: fix incorrect update of intr_delay_resolution
net: ena: fix retrieval of nonadaptive interrupt moderation intervals
net: ena: fix update of interrupt moderation register
net: ena: remove all old adaptive rx interrupt moderation code from ena_com
net: ena: remove ena_restore_ethtool_params() and relevant fields
net: ena: remove old adaptive interrupt moderation code from ena_netdev
net: ena: remove code duplication in ena_com_update_nonadaptive_moderation_interval _*()
net: ena: enable the interrupt_moderation in driver_supported_features
net: ena: reimplement set/get_coalesce()
net: ena: switch to dim algorithm for rx adaptive interrupt moderation
net: ena: add intr_moder_rx_interval to struct ena_com_dev and use it
net: phy: adin: implement Energy Detect Powerdown mode via phy-tunable
ethtool: implement Energy Detect Powerdown support via phy-tunable
xen-netfront: do not assume sk_buff_head list is empty in error handling
s390/ctcm: Delete unnecessary checks before the macro call “dev_kfree_skb”
net: ena: don't wake up tx queue when down
drop_monitor: Better sanitize notified packets
...
Diffstat (limited to 'net/can/j1939/address-claim.c')
-rw-r--r-- | net/can/j1939/address-claim.c | 230 |
1 files changed, 230 insertions, 0 deletions
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); + } +} |