From 456a8a646b2563438c16a9b27decf9aa717f1ebb Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Sat, 10 Aug 2019 21:18:10 +0200 Subject: [PATCH] can: gw: add support for CAN FD frames Introduce CAN FD support which needs an extension of the netlink API to pass CAN FD type content to the kernel which has a different size to Classic CAN. Additionally the struct canfd_frame has a new 'flags' element that can now be modified with can-gw. The new CGW_FLAGS_CAN_FD option flag defines whether the routing job handles Classic CAN or CAN FD frames. This setting is very strict at reception time and enables the new possibilities, e.g. CGW_FDMOD_* and modifying the flags element of struct canfd_frame, only when CGW_FLAGS_CAN_FD is set. Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- include/uapi/linux/can/gw.h | 14 ++- net/can/gw.c | 214 +++++++++++++++++++++++++++++++----- 2 files changed, 200 insertions(+), 28 deletions(-) diff --git a/include/uapi/linux/can/gw.h b/include/uapi/linux/can/gw.h index ed811bc463b5..3aea5388c8e4 100644 --- a/include/uapi/linux/can/gw.h +++ b/include/uapi/linux/can/gw.h @@ -80,6 +80,10 @@ enum { CGW_DELETED, /* number of deleted CAN frames (see max_hops param) */ CGW_LIM_HOPS, /* limit the number of hops of this specific rule */ CGW_MOD_UID, /* user defined identifier for modification updates */ + CGW_FDMOD_AND, /* CAN FD frame modification binary AND */ + CGW_FDMOD_OR, /* CAN FD frame modification binary OR */ + CGW_FDMOD_XOR, /* CAN FD frame modification binary XOR */ + CGW_FDMOD_SET, /* CAN FD frame modification set alternate values */ __CGW_MAX }; @@ -88,6 +92,7 @@ enum { #define CGW_FLAGS_CAN_ECHO 0x01 #define CGW_FLAGS_CAN_SRC_TSTAMP 0x02 #define CGW_FLAGS_CAN_IIF_TX_OK 0x04 +#define CGW_FLAGS_CAN_FD 0x08 #define CGW_MOD_FUNCS 4 /* AND OR XOR SET */ @@ -96,8 +101,9 @@ enum { #define CGW_MOD_DLC 0x02 /* contains the data length in bytes */ #define CGW_MOD_LEN CGW_MOD_DLC /* CAN FD length representation */ #define CGW_MOD_DATA 0x04 +#define CGW_MOD_FLAGS 0x08 /* CAN FD flags */ -#define CGW_FRAME_MODS 3 /* ID DLC/LEN DATA */ +#define CGW_FRAME_MODS 4 /* ID DLC/LEN DATA FLAGS */ #define MAX_MODFUNCTIONS (CGW_MOD_FUNCS * CGW_FRAME_MODS) @@ -106,7 +112,13 @@ struct cgw_frame_mod { __u8 modtype; } __attribute__((packed)); +struct cgw_fdframe_mod { + struct canfd_frame cf; + __u8 modtype; +} __attribute__((packed)); + #define CGW_MODATTR_LEN sizeof(struct cgw_frame_mod) +#define CGW_FDMODATTR_LEN sizeof(struct cgw_fdframe_mod) struct cgw_csum_xor { __s8 from_idx; diff --git a/net/can/gw.c b/net/can/gw.c index 3a1ad206fbef..65d60c93af29 100644 --- a/net/can/gw.c +++ b/net/can/gw.c @@ -1,7 +1,7 @@ // SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) /* gw.c - CAN frame Gateway/Router/Bridge with netlink interface * - * Copyright (c) 2017 Volkswagen Group Electronic Research + * Copyright (c) 2019 Volkswagen Group Electronic Research * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -59,7 +59,7 @@ #include #include -#define CAN_GW_VERSION "20170425" +#define CAN_GW_VERSION "20190810" #define CAN_GW_NAME "can-gw" MODULE_DESCRIPTION("PF_CAN netlink gateway"); @@ -156,17 +156,50 @@ struct cgw_job { MODFUNC(mod_and_id, cf->can_id &= mod->modframe.and.can_id) MODFUNC(mod_and_len, cf->len &= mod->modframe.and.len) +MODFUNC(mod_and_flags, cf->flags &= mod->modframe.and.flags) MODFUNC(mod_and_data, *(u64 *)cf->data &= *(u64 *)mod->modframe.and.data) MODFUNC(mod_or_id, cf->can_id |= mod->modframe.or.can_id) MODFUNC(mod_or_len, cf->len |= mod->modframe.or.len) +MODFUNC(mod_or_flags, cf->flags |= mod->modframe.or.flags) MODFUNC(mod_or_data, *(u64 *)cf->data |= *(u64 *)mod->modframe.or.data) MODFUNC(mod_xor_id, cf->can_id ^= mod->modframe.xor.can_id) MODFUNC(mod_xor_len, cf->len ^= mod->modframe.xor.len) +MODFUNC(mod_xor_flags, cf->flags ^= mod->modframe.xor.flags) MODFUNC(mod_xor_data, *(u64 *)cf->data ^= *(u64 *)mod->modframe.xor.data) MODFUNC(mod_set_id, cf->can_id = mod->modframe.set.can_id) MODFUNC(mod_set_len, cf->len = mod->modframe.set.len) +MODFUNC(mod_set_flags, cf->flags = mod->modframe.set.flags) MODFUNC(mod_set_data, *(u64 *)cf->data = *(u64 *)mod->modframe.set.data) +static void mod_and_fddata(struct canfd_frame *cf, struct cf_mod *mod) +{ + int i; + + for (i = 0; i < CANFD_MAX_DLEN; i += 8) + *(u64 *)(cf->data + i) &= *(u64 *)(mod->modframe.and.data + i); +} + +static void mod_or_fddata(struct canfd_frame *cf, struct cf_mod *mod) +{ + int i; + + for (i = 0; i < CANFD_MAX_DLEN; i += 8) + *(u64 *)(cf->data + i) |= *(u64 *)(mod->modframe.or.data + i); +} + +static void mod_xor_fddata(struct canfd_frame *cf, struct cf_mod *mod) +{ + int i; + + for (i = 0; i < CANFD_MAX_DLEN; i += 8) + *(u64 *)(cf->data + i) ^= *(u64 *)(mod->modframe.xor.data + i); +} + +static void mod_set_fddata(struct canfd_frame *cf, struct cf_mod *mod) +{ + memcpy(cf->data, mod->modframe.set.data, CANFD_MAX_DLEN); +} + static void canframecpy(struct canfd_frame *dst, struct can_frame *src) { /* Copy the struct members separately to ensure that no uninitialized @@ -179,10 +212,26 @@ static void canframecpy(struct canfd_frame *dst, struct can_frame *src) *(u64 *)dst->data = *(u64 *)src->data; } -static int cgw_chk_csum_parms(s8 fr, s8 to, s8 re) +static void canfdframecpy(struct canfd_frame *dst, struct canfd_frame *src) +{ + /* Copy the struct members separately to ensure that no uninitialized + * data are copied in the 2 bytes hole of the struct. This is needed + * to make easy compares of the data in the struct cf_mod. + */ + + dst->can_id = src->can_id; + dst->flags = src->flags; + dst->len = src->len; + memcpy(dst->data, src->data, CANFD_MAX_DLEN); +} + +static int cgw_chk_csum_parms(s8 fr, s8 to, s8 re, struct rtcanmsg *r) { s8 dlen = CAN_MAX_DLEN; + if (r->flags & CGW_FLAGS_CAN_FD) + dlen = CANFD_MAX_DLEN; + /* absolute dlc values 0 .. 7 => 0 .. 7, e.g. data [0] * relative to received dlc -1 .. -8 : * e.g. for received dlc = 8 @@ -351,6 +400,15 @@ static void can_can_gw_rcv(struct sk_buff *skb, void *data) struct sk_buff *nskb; int modidx = 0; + /* process strictly Classic CAN or CAN FD frames */ + if (gwj->flags & CGW_FLAGS_CAN_FD) { + if (skb->len != CANFD_MTU) + return; + } else { + if (skb->len != CAN_MTU) + return; + } + /* Do not handle CAN frames routed more than 'max_hops' times. * In general we should never catch this delimiter which is intended * to cover a misconfiguration protection (e.g. circular CAN routes). @@ -419,23 +477,19 @@ static void can_can_gw_rcv(struct sk_buff *skb, void *data) int max_len = nskb->len - offsetof(struct canfd_frame, data); /* dlc may have changed, make sure it fits to the CAN frame */ - if (cf->len > max_len) - goto out_delete; - - /* check for checksum updates in classic CAN length only */ - if (gwj->mod.csumfunc.crc8) { - if (cf->len > 8) - goto out_delete; - - (*gwj->mod.csumfunc.crc8)(cf, &gwj->mod.csum.crc8); + if (cf->len > max_len) { + /* delete frame due to misconfiguration */ + gwj->deleted_frames++; + kfree_skb(nskb); + return; } - if (gwj->mod.csumfunc.xor) { - if (cf->len > 8) - goto out_delete; + /* check for checksum updates */ + if (gwj->mod.csumfunc.crc8) + (*gwj->mod.csumfunc.crc8)(cf, &gwj->mod.csum.crc8); + if (gwj->mod.csumfunc.xor) (*gwj->mod.csumfunc.xor)(cf, &gwj->mod.csum.xor); - } } /* clear the skb timestamp if not configured the other way */ @@ -447,13 +501,6 @@ static void can_can_gw_rcv(struct sk_buff *skb, void *data) gwj->dropped_frames++; else gwj->handled_frames++; - - return; - - out_delete: - /* delete frame due to misconfiguration */ - gwj->deleted_frames++; - kfree_skb(nskb); } static inline int cgw_register_filter(struct net *net, struct cgw_job *gwj) @@ -535,7 +582,37 @@ static int cgw_put_job(struct sk_buff *skb, struct cgw_job *gwj, int type, goto cancel; } - if (1) { + if (gwj->flags & CGW_FLAGS_CAN_FD) { + struct cgw_fdframe_mod mb; + + if (gwj->mod.modtype.and) { + memcpy(&mb.cf, &gwj->mod.modframe.and, sizeof(mb.cf)); + mb.modtype = gwj->mod.modtype.and; + if (nla_put(skb, CGW_FDMOD_AND, sizeof(mb), &mb) < 0) + goto cancel; + } + + if (gwj->mod.modtype.or) { + memcpy(&mb.cf, &gwj->mod.modframe.or, sizeof(mb.cf)); + mb.modtype = gwj->mod.modtype.or; + if (nla_put(skb, CGW_FDMOD_OR, sizeof(mb), &mb) < 0) + goto cancel; + } + + if (gwj->mod.modtype.xor) { + memcpy(&mb.cf, &gwj->mod.modframe.xor, sizeof(mb.cf)); + mb.modtype = gwj->mod.modtype.xor; + if (nla_put(skb, CGW_FDMOD_XOR, sizeof(mb), &mb) < 0) + goto cancel; + } + + if (gwj->mod.modtype.set) { + memcpy(&mb.cf, &gwj->mod.modframe.set, sizeof(mb.cf)); + mb.modtype = gwj->mod.modtype.set; + if (nla_put(skb, CGW_FDMOD_SET, sizeof(mb), &mb) < 0) + goto cancel; + } + } else { struct cgw_frame_mod mb; if (gwj->mod.modtype.and) { @@ -645,6 +722,10 @@ static const struct nla_policy cgw_policy[CGW_MAX + 1] = { [CGW_FILTER] = { .len = sizeof(struct can_filter) }, [CGW_LIM_HOPS] = { .type = NLA_U8 }, [CGW_MOD_UID] = { .type = NLA_U32 }, + [CGW_FDMOD_AND] = { .len = sizeof(struct cgw_fdframe_mod) }, + [CGW_FDMOD_OR] = { .len = sizeof(struct cgw_fdframe_mod) }, + [CGW_FDMOD_XOR] = { .len = sizeof(struct cgw_fdframe_mod) }, + [CGW_FDMOD_SET] = { .len = sizeof(struct cgw_fdframe_mod) }, }; /* check for common and gwtype specific attributes */ @@ -652,6 +733,7 @@ static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod, u8 gwtype, void *gwtypeattr, u8 *limhops) { struct nlattr *tb[CGW_MAX + 1]; + struct rtcanmsg *r = nlmsg_data(nlh); int modidx = 0; int err = 0; @@ -671,7 +753,85 @@ static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod, } /* check for AND/OR/XOR/SET modifications */ - if (1) { + if (r->flags & CGW_FLAGS_CAN_FD) { + struct cgw_fdframe_mod mb; + + if (tb[CGW_FDMOD_AND]) { + nla_memcpy(&mb, tb[CGW_FDMOD_AND], CGW_FDMODATTR_LEN); + + canfdframecpy(&mod->modframe.and, &mb.cf); + mod->modtype.and = mb.modtype; + + if (mb.modtype & CGW_MOD_ID) + mod->modfunc[modidx++] = mod_and_id; + + if (mb.modtype & CGW_MOD_LEN) + mod->modfunc[modidx++] = mod_and_len; + + if (mb.modtype & CGW_MOD_FLAGS) + mod->modfunc[modidx++] = mod_and_flags; + + if (mb.modtype & CGW_MOD_DATA) + mod->modfunc[modidx++] = mod_and_fddata; + } + + if (tb[CGW_FDMOD_OR]) { + nla_memcpy(&mb, tb[CGW_FDMOD_OR], CGW_FDMODATTR_LEN); + + canfdframecpy(&mod->modframe.or, &mb.cf); + mod->modtype.or = mb.modtype; + + if (mb.modtype & CGW_MOD_ID) + mod->modfunc[modidx++] = mod_or_id; + + if (mb.modtype & CGW_MOD_LEN) + mod->modfunc[modidx++] = mod_or_len; + + if (mb.modtype & CGW_MOD_FLAGS) + mod->modfunc[modidx++] = mod_or_flags; + + if (mb.modtype & CGW_MOD_DATA) + mod->modfunc[modidx++] = mod_or_fddata; + } + + if (tb[CGW_FDMOD_XOR]) { + nla_memcpy(&mb, tb[CGW_FDMOD_XOR], CGW_FDMODATTR_LEN); + + canfdframecpy(&mod->modframe.xor, &mb.cf); + mod->modtype.xor = mb.modtype; + + if (mb.modtype & CGW_MOD_ID) + mod->modfunc[modidx++] = mod_xor_id; + + if (mb.modtype & CGW_MOD_LEN) + mod->modfunc[modidx++] = mod_xor_len; + + if (mb.modtype & CGW_MOD_FLAGS) + mod->modfunc[modidx++] = mod_xor_flags; + + if (mb.modtype & CGW_MOD_DATA) + mod->modfunc[modidx++] = mod_xor_fddata; + } + + if (tb[CGW_FDMOD_SET]) { + nla_memcpy(&mb, tb[CGW_FDMOD_SET], CGW_FDMODATTR_LEN); + + canfdframecpy(&mod->modframe.set, &mb.cf); + mod->modtype.set = mb.modtype; + + if (mb.modtype & CGW_MOD_ID) + mod->modfunc[modidx++] = mod_set_id; + + if (mb.modtype & CGW_MOD_LEN) + mod->modfunc[modidx++] = mod_set_len; + + if (mb.modtype & CGW_MOD_FLAGS) + mod->modfunc[modidx++] = mod_set_flags; + + if (mb.modtype & CGW_MOD_DATA) + mod->modfunc[modidx++] = mod_set_fddata; + } + } else { struct cgw_frame_mod mb; if (tb[CGW_MOD_AND]) { @@ -745,7 +905,7 @@ static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod, struct cgw_csum_crc8 *c = nla_data(tb[CGW_CS_CRC8]); err = cgw_chk_csum_parms(c->from_idx, c->to_idx, - c->result_idx); + c->result_idx, r); if (err) return err; @@ -768,7 +928,7 @@ static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod, struct cgw_csum_xor *c = nla_data(tb[CGW_CS_XOR]); err = cgw_chk_csum_parms(c->from_idx, c->to_idx, - c->result_idx); + c->result_idx, r); if (err) return err; -- 2.30.2