X-Git-Url: http://rtime.felk.cvut.cz/gitweb/socketcan-devel.git/blobdiff_plain/af24ff95b4f16087e3d226af157533c7e8d6fefe..932abb70dd7df77d197bab86d2db49f1a2c56f60:/kernel/2.6/net/can/gw.c diff --git a/kernel/2.6/net/can/gw.c b/kernel/2.6/net/can/gw.c index 7b999c7..d7257cc 100644 --- a/kernel/2.6/net/can/gw.c +++ b/kernel/2.6/net/can/gw.c @@ -1,7 +1,7 @@ /* * gw.c - CAN frame Gateway/Router/Bridge with netlink interface * - * Copyright (c) 2002-2010 Volkswagen Group Electronic Research + * Copyright (c) 2011 Volkswagen Group Electronic Research * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -48,6 +48,7 @@ #include #include #include +#include #include #include #include @@ -57,34 +58,27 @@ #include #include #include +#include #include /* for RCSID. Removed by mkpatch script */ RCSID("$Id$"); -#define CAN_GW_VERSION "20100222" +#define CAN_GW_VERSION "20101209" static __initdata const char banner[] = KERN_INFO "can: netlink gateway (rev " CAN_GW_VERSION ")\n"; MODULE_DESCRIPTION("PF_CAN netlink gateway"); MODULE_LICENSE("Dual BSD/GPL"); MODULE_AUTHOR("Oliver Hartkopp "); +MODULE_ALIAS("can-gw"); -HLIST_HEAD(can_gw_list); -static DEFINE_SPINLOCK(can_gw_list_lock); +HLIST_HEAD(cgw_list); static struct notifier_block notifier; -static struct kmem_cache *gw_cache __read_mostly; +static struct kmem_cache *cgw_cache __read_mostly; -#define GW_SK_MAGIC ((void *)(¬ifier)) - -/* - * So far we just support CAN -> CAN routing and frame modifications. - * - * The internal can_can_gw structure contains optional attributes for - * a CAN -> CAN gateway job. - */ -struct can_can_gw { - struct can_filter filter; +/* structure that contains the (on-the-fly) CAN frame modifications */ +struct cf_mod { struct { struct can_frame and; struct can_frame or; @@ -98,72 +92,79 @@ struct can_can_gw { u8 set; } modtype; void (*modfunc[MAX_MODFUNCTIONS])(struct can_frame *cf, - struct can_can_gw *mod); + struct cf_mod *mod); + + /* CAN frame checksum calculation after CAN frame modifications */ + struct { + struct cgw_csum_xor xor; + struct cgw_csum_crc8 crc8; + } csum; + struct { + void (*xor)(struct can_frame *cf, struct cgw_csum_xor *xor); + void (*crc8)(struct can_frame *cf, struct cgw_csum_crc8 *crc8); + } csumfunc; +}; + + +/* + * So far we just support CAN -> CAN routing and frame modifications. + * + * The internal can_can_gw structure contains data and attributes for + * a CAN -> CAN gateway job. + */ +struct can_can_gw { + struct can_filter filter; + int src_idx; + int dst_idx; }; /* list entry for CAN gateways jobs */ -struct gw_job { +struct cgw_job { struct hlist_node list; struct rcu_head rcu; - struct net_device *src_dev; - struct net_device *dst_dev; - u32 flags; u32 handled_frames; u32 dropped_frames; + struct cf_mod mod; + union { + /* CAN frame data source */ + struct net_device *dev; + } src; + union { + /* CAN frame data destination */ + struct net_device *dev; + } dst; union { struct can_can_gw ccgw; /* tbc */ }; + u8 gwtype; + u16 flags; }; -/* content of u32 gwjob.flags */ -#define CAN_TX_ECHO 0x00000001 -#define CAN_TX_SRC_TSTAMP 0x00000002 +/* modification functions that are invoked in the hot path in can_can_gw_rcv */ -/* modification functions that are invoked in the hot path in gw_rcv */ -void mod_and_id (struct can_frame *cf, struct can_can_gw *mod) { - cf->can_id &= mod->modframe.and.can_id; -} -void mod_and_dlc (struct can_frame *cf, struct can_can_gw *mod) { - cf->can_dlc &= mod->modframe.and.can_dlc; -} -void mod_and_data (struct can_frame *cf, struct can_can_gw *mod) { - *(u64 *)cf->data &= *(u64 *)mod->modframe.and.data; -} -void mod_or_id (struct can_frame *cf, struct can_can_gw *mod) { - cf->can_id |= mod->modframe.or.can_id; -} -void mod_or_dlc (struct can_frame *cf, struct can_can_gw *mod) { - cf->can_dlc |= mod->modframe.or.can_dlc; -} -void mod_or_data (struct can_frame *cf, struct can_can_gw *mod) { - *(u64 *)cf->data |= *(u64 *)mod->modframe.or.data; -} -void mod_xor_id (struct can_frame *cf, struct can_can_gw *mod) { - cf->can_id ^= mod->modframe.xor.can_id; -} -void mod_xor_dlc (struct can_frame *cf, struct can_can_gw *mod) { - cf->can_dlc ^= mod->modframe.xor.can_dlc; -} -void mod_xor_data (struct can_frame *cf, struct can_can_gw *mod) { - *(u64 *)cf->data ^= *(u64 *)mod->modframe.xor.data; -} -void mod_set_id (struct can_frame *cf, struct can_can_gw *mod) { - cf->can_id = mod->modframe.set.can_id; -} -void mod_set_dlc (struct can_frame *cf, struct can_can_gw *mod) { - cf->can_dlc = mod->modframe.set.can_dlc; -} -void mod_set_data (struct can_frame *cf, struct can_can_gw *mod) { - *(u64 *)cf->data = *(u64 *)mod->modframe.set.data; -} +#define MODFUNC(func, op) static void func(struct can_frame *cf, \ + struct cf_mod *mod) { op ; } + +MODFUNC(mod_and_id, cf->can_id &= mod->modframe.and.can_id) +MODFUNC(mod_and_dlc, cf->can_dlc &= mod->modframe.and.can_dlc) +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_dlc, cf->can_dlc |= mod->modframe.or.can_dlc) +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_dlc, cf->can_dlc ^= mod->modframe.xor.can_dlc) +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_dlc, cf->can_dlc = mod->modframe.set.can_dlc) +MODFUNC(mod_set_data, *(u64 *)cf->data = *(u64 *)mod->modframe.set.data) static inline void canframecpy(struct can_frame *dst, struct can_frame *src) { /* * Copy the struct members separately to ensure that no uninitialized * data are copied in the 3 bytes hole of the struct. This is needed - * to make easy compares of the data in the struct can_can_gw. + * to make easy compares of the data in the struct cf_mod. */ dst->can_id = src->can_id; @@ -171,19 +172,183 @@ static inline void canframecpy(struct can_frame *dst, struct can_frame *src) *(u64 *)dst->data = *(u64 *)src->data; } +static int cgw_chk_csum_parms(s8 fr, s8 to, s8 re) +{ + /* + * absolute dlc values 0 .. 7 => 0 .. 7, e.g. data [0] + * relative to received dlc -1 .. -8 : + * e.g. for received dlc = 8 + * -1 => index = 7 (data[7]) + * -3 => index = 5 (data[5]) + * -8 => index = 0 (data[0]) + */ + + if (fr > -9 && fr < 8 && + to > -9 && to < 8 && + re > -9 && re < 8) + return 0; + else + return -EINVAL; +} + +static inline int calc_idx(int idx, int rx_dlc) +{ + if (idx < 0) + return rx_dlc + idx; + else + return idx; +} + +static void cgw_csum_xor_rel(struct can_frame *cf, struct cgw_csum_xor *xor) +{ + int from = calc_idx(xor->from_idx, cf->can_dlc); + int to = calc_idx(xor->to_idx, cf->can_dlc); + int res = calc_idx(xor->result_idx, cf->can_dlc); + u8 val = xor->init_xor_val; + int i; + + if (from < 0 || to < 0 || res < 0) + return; + + if (from <= to) { + for (i = from; i <= to; i++) + val ^= cf->data[i]; + } else { + for (i = from; i >= to; i--) + val ^= cf->data[i]; + } + + cf->data[res] = val; +} + +static void cgw_csum_xor_pos(struct can_frame *cf, struct cgw_csum_xor *xor) +{ + u8 val = xor->init_xor_val; + int i; + + for (i = xor->from_idx; i <= xor->to_idx; i++) + val ^= cf->data[i]; + + cf->data[xor->result_idx] = val; +} + +static void cgw_csum_xor_neg(struct can_frame *cf, struct cgw_csum_xor *xor) +{ + u8 val = xor->init_xor_val; + int i; + + for (i = xor->from_idx; i >= xor->to_idx; i--) + val ^= cf->data[i]; + + cf->data[xor->result_idx] = val; +} + +static void cgw_csum_crc8_rel(struct can_frame *cf, struct cgw_csum_crc8 *crc8) +{ + int from = calc_idx(crc8->from_idx, cf->can_dlc); + int to = calc_idx(crc8->to_idx, cf->can_dlc); + int res = calc_idx(crc8->result_idx, cf->can_dlc); + u8 crc = crc8->init_crc_val; + int i; + + if (from < 0 || to < 0 || res < 0) + return; + + if (from <= to) { + for (i = crc8->from_idx; i <= crc8->to_idx; i++) + crc = crc8->crctab[crc^cf->data[i]]; + } else { + for (i = crc8->from_idx; i >= crc8->to_idx; i--) + crc = crc8->crctab[crc^cf->data[i]]; + } + + switch (crc8->profile) { + + case CGW_CRC8PRF_1U8: + crc = crc8->crctab[crc^crc8->profile_data[0]]; + break; + + case CGW_CRC8PRF_16U8: + crc = crc8->crctab[crc^crc8->profile_data[cf->data[1] & 0xF]]; + break; + + case CGW_CRC8PRF_SFFID_XOR: + crc = crc8->crctab[crc^(cf->can_id & 0xFF)^ + (cf->can_id >> 8 & 0xFF)]; + break; + + } + + cf->data[crc8->result_idx] = crc^crc8->final_xor_val; +} + +static void cgw_csum_crc8_pos(struct can_frame *cf, struct cgw_csum_crc8 *crc8) +{ + u8 crc = crc8->init_crc_val; + int i; + + for (i = crc8->from_idx; i <= crc8->to_idx; i++) + crc = crc8->crctab[crc^cf->data[i]]; + + switch (crc8->profile) { + + case CGW_CRC8PRF_1U8: + crc = crc8->crctab[crc^crc8->profile_data[0]]; + break; + + case CGW_CRC8PRF_16U8: + crc = crc8->crctab[crc^crc8->profile_data[cf->data[1] & 0xF]]; + break; + + case CGW_CRC8PRF_SFFID_XOR: + crc = crc8->crctab[crc^(cf->can_id & 0xFF)^ + (cf->can_id >> 8 & 0xFF)]; + break; + } + + cf->data[crc8->result_idx] = crc^crc8->final_xor_val; +} + +static void cgw_csum_crc8_neg(struct can_frame *cf, struct cgw_csum_crc8 *crc8) +{ + u8 crc = crc8->init_crc_val; + int i; + + for (i = crc8->from_idx; i >= crc8->to_idx; i--) + crc = crc8->crctab[crc^cf->data[i]]; + + switch (crc8->profile) { + + case CGW_CRC8PRF_1U8: + crc = crc8->crctab[crc^crc8->profile_data[0]]; + break; + + case CGW_CRC8PRF_16U8: + crc = crc8->crctab[crc^crc8->profile_data[cf->data[1] & 0xF]]; + break; + + case CGW_CRC8PRF_SFFID_XOR: + crc = crc8->crctab[crc^(cf->can_id & 0xFF)^ + (cf->can_id >> 8 & 0xFF)]; + break; + } + + cf->data[crc8->result_idx] = crc^crc8->final_xor_val; +} + /* the receive & process & send function */ -static void gw_rcv(struct sk_buff *skb, void *data) +static void can_can_gw_rcv(struct sk_buff *skb, void *data) { - struct gw_job *gwj = (struct gw_job *)data; + struct cgw_job *gwj = (struct cgw_job *)data; struct can_frame *cf; struct sk_buff *nskb; int modidx = 0; - /* do not handle already routed frames */ - if (skb->sk == GW_SK_MAGIC) + /* do not handle already routed frames - see comment below */ + if (skb_mac_header_was_set(skb)) return; - if (!(gwj->dst_dev->flags & IFF_UP)) { + if (!(gwj->dst.dev->flags & IFF_UP)) { gwj->dropped_frames++; return; } @@ -194,7 +359,7 @@ static void gw_rcv(struct sk_buff *skb, void *data) * When there is at least one modification function activated, * we need to copy the skb as we want to modify skb->data. */ - if (gwj->ccgw.modfunc[0]) + if (gwj->mod.modfunc[0]) nskb = skb_copy(skb, GFP_ATOMIC); else nskb = skb_clone(skb, GFP_ATOMIC); @@ -204,41 +369,58 @@ static void gw_rcv(struct sk_buff *skb, void *data) return; } - /* mark routed frames with a 'special' sk value */ - nskb->sk = GW_SK_MAGIC; - nskb->dev = gwj->dst_dev; + /* + * Mark routed frames by setting some mac header length which is + * not relevant for the CAN frames located in the skb->data section. + * + * As dev->header_ops is not set in CAN netdevices no one is ever + * accessing the various header offsets in the CAN skbuffs anyway. + * E.g. using the packet socket to read CAN frames is still working. + */ + skb_set_mac_header(nskb, 8); + nskb->dev = gwj->dst.dev; /* pointer to modifiable CAN frame */ cf = (struct can_frame *)nskb->data; /* perform preprocessed modification functions if there are any */ - while (modidx < MAX_MODFUNCTIONS && gwj->ccgw.modfunc[modidx]) - (*gwj->ccgw.modfunc[modidx++])(cf, &gwj->ccgw); + while (modidx < MAX_MODFUNCTIONS && gwj->mod.modfunc[modidx]) + (*gwj->mod.modfunc[modidx++])(cf, &gwj->mod); + + /* check for checksum updates when the CAN frame has been modified */ + if (modidx) { + 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 */ - if (!(gwj->flags & CAN_TX_SRC_TSTAMP)) + if (!(gwj->flags & CGW_FLAGS_CAN_SRC_TSTAMP)) nskb->tstamp.tv64 = 0; /* send to netdevice */ - if (can_send(nskb, gwj->flags & CAN_TX_ECHO)) + if (can_send(nskb, gwj->flags & CGW_FLAGS_CAN_ECHO)) gwj->dropped_frames++; else gwj->handled_frames++; } -static inline int can_gw_register_filter(struct gw_job *gwj) +static inline int cgw_register_filter(struct cgw_job *gwj) { - return can_rx_register(gwj->src_dev, gwj->ccgw.filter.can_id, - gwj->ccgw.filter.can_mask, gw_rcv, gwj, "gw"); + return can_rx_register(gwj->src.dev, gwj->ccgw.filter.can_id, + gwj->ccgw.filter.can_mask, can_can_gw_rcv, + gwj, "gw"); } -static inline void can_gw_unregister_filter(struct gw_job *gwj) +static inline void cgw_unregister_filter(struct cgw_job *gwj) { - can_rx_unregister(gwj->src_dev, gwj->ccgw.filter.can_id, - gwj->ccgw.filter.can_mask, gw_rcv, gwj); + can_rx_unregister(gwj->src.dev, gwj->ccgw.filter.can_id, + gwj->ccgw.filter.can_mask, can_can_gw_rcv, gwj); } -static int gw_notifier(struct notifier_block *nb, +static int cgw_notifier(struct notifier_block *nb, unsigned long msg, void *data) { struct net_device *dev = (struct net_device *)data; @@ -255,33 +437,27 @@ static int gw_notifier(struct notifier_block *nb, if (msg == NETDEV_UNREGISTER) { - struct gw_job *gwj = NULL; + struct cgw_job *gwj = NULL; struct hlist_node *n, *nx; - spin_lock(&can_gw_list_lock); + ASSERT_RTNL(); - hlist_for_each_entry_safe(gwj, n, nx, &can_gw_list, list) { + hlist_for_each_entry_safe(gwj, n, nx, &cgw_list, list) { - if (gwj->src_dev == dev || gwj->dst_dev == dev) { + if (gwj->src.dev == dev || gwj->dst.dev == dev) { hlist_del(&gwj->list); - can_gw_unregister_filter(gwj); + cgw_unregister_filter(gwj); kfree(gwj); } } - - spin_unlock(&can_gw_list_lock); } return NOTIFY_DONE; } -static int gw_put_job(struct sk_buff *skb, struct gw_job *gwj) +static int cgw_put_job(struct sk_buff *skb, struct cgw_job *gwj) { - struct { - struct can_frame cf; - u8 modtype; - } __attribute__((packed)) mb; - + struct cgw_frame_mod mb; struct rtcanmsg *rtcan; struct nlmsghdr *nlh = nlmsg_put(skb, 0, 0, 0, sizeof(*rtcan), 0); if (!nlh) @@ -289,17 +465,11 @@ static int gw_put_job(struct sk_buff *skb, struct gw_job *gwj) rtcan = nlmsg_data(nlh); rtcan->can_family = AF_CAN; - rtcan->src_ifindex = gwj->src_dev->ifindex; - rtcan->dst_ifindex = gwj->dst_dev->ifindex; - rtcan->can_txflags = 0; + rtcan->gwtype = gwj->gwtype; + rtcan->flags = gwj->flags; - if (gwj->flags & CAN_TX_ECHO) - rtcan->can_txflags |= CAN_GW_TXFLAGS_ECHO; + /* add statistics if available */ - if (gwj->flags & CAN_TX_SRC_TSTAMP) - rtcan->can_txflags |= CAN_GW_TXFLAGS_SRC_TSTAMP; - - /* check non default settings of attributes */ if (gwj->handled_frames) { if (nla_put_u32(skb, CGW_HANDLED, gwj->handled_frames) < 0) goto cancel; @@ -314,51 +484,84 @@ static int gw_put_job(struct sk_buff *skb, struct gw_job *gwj) nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN(sizeof(u32)); } - if (gwj->ccgw.filter.can_id || gwj->ccgw.filter.can_mask) { - if (nla_put(skb, CGW_FILTER, sizeof(struct can_filter), - &gwj->ccgw.filter) < 0) - goto cancel; - else - nlh->nlmsg_len += NLA_HDRLEN + - NLA_ALIGN(sizeof(struct can_filter)); - } + /* check non default settings of attributes */ - if (gwj->ccgw.modtype.and) { - memcpy(&mb.cf, &gwj->ccgw.modframe.and, sizeof(mb.cf)); - mb.modtype = gwj->ccgw.modtype.and; + 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_MOD_AND, sizeof(mb), &mb) < 0) goto cancel; else nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN(sizeof(mb)); } - if (gwj->ccgw.modtype.or) { - memcpy(&mb.cf, &gwj->ccgw.modframe.or, sizeof(mb.cf)); - mb.modtype = gwj->ccgw.modtype.or; + 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_MOD_OR, sizeof(mb), &mb) < 0) goto cancel; else nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN(sizeof(mb)); } - if (gwj->ccgw.modtype.xor) { - memcpy(&mb.cf, &gwj->ccgw.modframe.xor, sizeof(mb.cf)); - mb.modtype = gwj->ccgw.modtype.xor; + 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_MOD_XOR, sizeof(mb), &mb) < 0) goto cancel; else nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN(sizeof(mb)); } - if (gwj->ccgw.modtype.set) { - memcpy(&mb.cf, &gwj->ccgw.modframe.set, sizeof(mb.cf)); - mb.modtype = gwj->ccgw.modtype.set; + 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_MOD_SET, sizeof(mb), &mb) < 0) goto cancel; else nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN(sizeof(mb)); } + if (gwj->mod.csumfunc.crc8) { + if (nla_put(skb, CGW_CS_CRC8, CGW_CS_CRC8_LEN, + &gwj->mod.csum.crc8) < 0) + goto cancel; + else + nlh->nlmsg_len += NLA_HDRLEN + \ + NLA_ALIGN(CGW_CS_CRC8_LEN); + } + + if (gwj->mod.csumfunc.xor) { + if (nla_put(skb, CGW_CS_XOR, CGW_CS_XOR_LEN, + &gwj->mod.csum.xor) < 0) + goto cancel; + else + nlh->nlmsg_len += NLA_HDRLEN + \ + NLA_ALIGN(CGW_CS_XOR_LEN); + } + + if (gwj->gwtype == CGW_TYPE_CAN_CAN) { + + if (gwj->ccgw.filter.can_id || gwj->ccgw.filter.can_mask) { + if (nla_put(skb, CGW_FILTER, sizeof(struct can_filter), + &gwj->ccgw.filter) < 0) + goto cancel; + else + nlh->nlmsg_len += NLA_HDRLEN + + NLA_ALIGN(sizeof(struct can_filter)); + } + + if (nla_put_u32(skb, CGW_SRC_IF, gwj->ccgw.src_idx) < 0) + goto cancel; + else + nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN(sizeof(u32)); + + if (nla_put_u32(skb, CGW_DST_IF, gwj->ccgw.dst_idx) < 0) + goto cancel; + else + nlh->nlmsg_len += NLA_HDRLEN + NLA_ALIGN(sizeof(u32)); + } + return skb->len; cancel: @@ -367,313 +570,399 @@ cancel: } /* Dump information about all CAN gateway jobs, in response to RTM_GETROUTE */ -static int gw_dump_jobs(struct sk_buff *skb, struct netlink_callback *cb) +static int cgw_dump_jobs(struct sk_buff *skb, struct netlink_callback *cb) { - struct gw_job *gwj = NULL; + struct cgw_job *gwj = NULL; struct hlist_node *n; int idx = 0; - int ret = 0; + int s_idx = cb->args[0]; rcu_read_lock(); - hlist_for_each_entry_rcu(gwj, n, &can_gw_list, list) { - if (idx >= cb->args[0]) { - ret = gw_put_job(skb, gwj); - if (ret > 0) - cb->args[0]++; + hlist_for_each_entry_rcu(gwj, n, &cgw_list, list) { + if (idx < s_idx) + goto cont; + + if (cgw_put_job(skb, gwj) < 0) break; - } +cont: idx++; } rcu_read_unlock(); - return ret; + cb->args[0] = idx; + + return skb->len; } -/* check for attributes / filters for the CAN->CAN gateway */ -static int can_can_parse_attr(struct nlmsghdr *nlh, struct can_can_gw *ccgw) +/* check for common and gwtype specific attributes */ +static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod, + u8 gwtype, void *gwtypeattr) { struct nlattr *tb[CGW_MAX+1]; + struct cgw_frame_mod mb; int modidx = 0; int err = 0; - struct { - struct can_frame cf; - u8 modtype; - } __attribute__((packed)) mb; - - BUILD_BUG_ON(sizeof(mb) != CGW_MODATTR_LEN); - - memset(ccgw, 0, sizeof(*ccgw)); + /* initialize modification & checksum data space */ + memset(mod, 0, sizeof(*mod)); err = nlmsg_parse(nlh, sizeof(struct rtcanmsg), tb, CGW_MAX, NULL); if (err < 0) return err; - /* check for can_filter in attributes */ - if (tb[CGW_FILTER] && - nla_len(tb[CGW_FILTER]) == sizeof(struct can_filter)) - nla_memcpy(&ccgw->filter, tb[CGW_FILTER], - sizeof(struct can_filter)); - /* check for AND/OR/XOR/SET modifications */ + if (tb[CGW_MOD_AND] && nla_len(tb[CGW_MOD_AND]) == CGW_MODATTR_LEN) { nla_memcpy(&mb, tb[CGW_MOD_AND], CGW_MODATTR_LEN); - canframecpy(&ccgw->modframe.and, &mb.cf); - ccgw->modtype.and = mb.modtype; + canframecpy(&mod->modframe.and, &mb.cf); + mod->modtype.and = mb.modtype; if (mb.modtype & CGW_MOD_ID) - ccgw->modfunc[modidx++] = mod_and_id; + mod->modfunc[modidx++] = mod_and_id; if (mb.modtype & CGW_MOD_DLC) - ccgw->modfunc[modidx++] = mod_and_dlc; + mod->modfunc[modidx++] = mod_and_dlc; if (mb.modtype & CGW_MOD_DATA) - ccgw->modfunc[modidx++] = mod_and_data; + mod->modfunc[modidx++] = mod_and_data; } if (tb[CGW_MOD_OR] && nla_len(tb[CGW_MOD_OR]) == CGW_MODATTR_LEN) { nla_memcpy(&mb, tb[CGW_MOD_OR], CGW_MODATTR_LEN); - canframecpy(&ccgw->modframe.or, &mb.cf); - ccgw->modtype.or = mb.modtype; + canframecpy(&mod->modframe.or, &mb.cf); + mod->modtype.or = mb.modtype; if (mb.modtype & CGW_MOD_ID) - ccgw->modfunc[modidx++] = mod_or_id; + mod->modfunc[modidx++] = mod_or_id; if (mb.modtype & CGW_MOD_DLC) - ccgw->modfunc[modidx++] = mod_or_dlc; + mod->modfunc[modidx++] = mod_or_dlc; if (mb.modtype & CGW_MOD_DATA) - ccgw->modfunc[modidx++] = mod_or_data; + mod->modfunc[modidx++] = mod_or_data; } if (tb[CGW_MOD_XOR] && nla_len(tb[CGW_MOD_XOR]) == CGW_MODATTR_LEN) { nla_memcpy(&mb, tb[CGW_MOD_XOR], CGW_MODATTR_LEN); - canframecpy(&ccgw->modframe.xor, &mb.cf); - ccgw->modtype.xor = mb.modtype; + canframecpy(&mod->modframe.xor, &mb.cf); + mod->modtype.xor = mb.modtype; if (mb.modtype & CGW_MOD_ID) - ccgw->modfunc[modidx++] = mod_xor_id; + mod->modfunc[modidx++] = mod_xor_id; if (mb.modtype & CGW_MOD_DLC) - ccgw->modfunc[modidx++] = mod_xor_dlc; + mod->modfunc[modidx++] = mod_xor_dlc; if (mb.modtype & CGW_MOD_DATA) - ccgw->modfunc[modidx++] = mod_xor_data; + mod->modfunc[modidx++] = mod_xor_data; } if (tb[CGW_MOD_SET] && nla_len(tb[CGW_MOD_SET]) == CGW_MODATTR_LEN) { nla_memcpy(&mb, tb[CGW_MOD_SET], CGW_MODATTR_LEN); - canframecpy(&ccgw->modframe.set, &mb.cf); - ccgw->modtype.set = mb.modtype; + canframecpy(&mod->modframe.set, &mb.cf); + mod->modtype.set = mb.modtype; if (mb.modtype & CGW_MOD_ID) - ccgw->modfunc[modidx++] = mod_set_id; + mod->modfunc[modidx++] = mod_set_id; if (mb.modtype & CGW_MOD_DLC) - ccgw->modfunc[modidx++] = mod_set_dlc; + mod->modfunc[modidx++] = mod_set_dlc; if (mb.modtype & CGW_MOD_DATA) - ccgw->modfunc[modidx++] = mod_set_data; + mod->modfunc[modidx++] = mod_set_data; } + /* check for checksum operations after CAN frame modifications */ + if (modidx) { + + if (tb[CGW_CS_CRC8] && + nla_len(tb[CGW_CS_CRC8]) == CGW_CS_CRC8_LEN) { + + struct cgw_csum_crc8 *c = (struct cgw_csum_crc8 *)\ + nla_data(tb[CGW_CS_CRC8]); + + err = cgw_chk_csum_parms(c->from_idx, c->to_idx, + c->result_idx); + if (err) + return err; + + nla_memcpy(&mod->csum.crc8, tb[CGW_CS_CRC8], + CGW_CS_CRC8_LEN); + + /* + * select dedicated processing function to reduce + * runtime operations in receive hot path. + */ + if (c->from_idx < 0 || c->to_idx < 0 || + c->result_idx < 0) + mod->csumfunc.crc8 = cgw_csum_crc8_rel; + else if (c->from_idx <= c->to_idx) + mod->csumfunc.crc8 = cgw_csum_crc8_pos; + else + mod->csumfunc.crc8 = cgw_csum_crc8_neg; + } + + if (tb[CGW_CS_XOR] && + nla_len(tb[CGW_CS_XOR]) == CGW_CS_XOR_LEN) { + + struct cgw_csum_xor *c = (struct cgw_csum_xor *)\ + nla_data(tb[CGW_CS_XOR]); + + err = cgw_chk_csum_parms(c->from_idx, c->to_idx, + c->result_idx); + if (err) + return err; + + nla_memcpy(&mod->csum.xor, tb[CGW_CS_XOR], + CGW_CS_XOR_LEN); + + /* + * select dedicated processing function to reduce + * runtime operations in receive hot path. + */ + if (c->from_idx < 0 || c->to_idx < 0 || + c->result_idx < 0) + mod->csumfunc.xor = cgw_csum_xor_rel; + else if (c->from_idx <= c->to_idx) + mod->csumfunc.xor = cgw_csum_xor_pos; + else + mod->csumfunc.xor = cgw_csum_xor_neg; + } + } + + if (gwtype == CGW_TYPE_CAN_CAN) { + + /* check CGW_TYPE_CAN_CAN specific attributes */ + + struct can_can_gw *ccgw = (struct can_can_gw *)gwtypeattr; + memset(ccgw, 0, sizeof(*ccgw)); + + /* check for can_filter in attributes */ + if (tb[CGW_FILTER] && + nla_len(tb[CGW_FILTER]) == sizeof(struct can_filter)) + nla_memcpy(&ccgw->filter, tb[CGW_FILTER], + sizeof(struct can_filter)); + + err = -ENODEV; + + /* specifying two interfaces is mandatory */ + if (!tb[CGW_SRC_IF] || !tb[CGW_DST_IF]) + return err; + + if (nla_len(tb[CGW_SRC_IF]) == sizeof(u32)) + nla_memcpy(&ccgw->src_idx, tb[CGW_SRC_IF], + sizeof(u32)); + + if (nla_len(tb[CGW_DST_IF]) == sizeof(u32)) + nla_memcpy(&ccgw->dst_idx, tb[CGW_DST_IF], + sizeof(u32)); + + /* both indices set to 0 for flushing all routing entries */ + if (!ccgw->src_idx && !ccgw->dst_idx) + return 0; + + /* only one index set to 0 is an error */ + if (!ccgw->src_idx || !ccgw->dst_idx) + return err; + } + + /* add the checks for other gwtypes here */ + return 0; } -static int gw_create_job(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) +static int cgw_create_job(struct sk_buff *skb, struct nlmsghdr *nlh, + void *arg) { struct rtcanmsg *r; - struct gw_job *gwj; + struct cgw_job *gwj; int err = 0; if (nlmsg_len(nlh) < sizeof(*r)) - return -EINVAL; + return -EINVAL; + + r = nlmsg_data(nlh); + if (r->can_family != AF_CAN) + return -EPFNOSUPPORT; - r = nlmsg_data(nlh); - if (r->can_family != AF_CAN) - return -EPFNOSUPPORT; + /* so far we only support CAN -> CAN routings */ + if (r->gwtype != CGW_TYPE_CAN_CAN) + return -EINVAL; - gwj = kmem_cache_alloc(gw_cache, GFP_KERNEL); + gwj = kmem_cache_alloc(cgw_cache, GFP_KERNEL); if (!gwj) return -ENOMEM; - gwj->src_dev = dev_get_by_index(&init_net, r->src_ifindex); - if (!gwj->src_dev) { - err = -ENODEV; - goto fail; - } + gwj->handled_frames = 0; + gwj->dropped_frames = 0; + gwj->flags = r->flags; + gwj->gwtype = r->gwtype; - /* for now the source device needs to be a CAN device */ - if (gwj->src_dev->type != ARPHRD_CAN) { - err = -ENODEV; - goto put_src_fail; - } + err = cgw_parse_attr(nlh, &gwj->mod, CGW_TYPE_CAN_CAN, &gwj->ccgw); + if (err < 0) + goto out; - gwj->dst_dev = dev_get_by_index(&init_net, r->dst_ifindex); - if (!gwj->dst_dev) { - err = -ENODEV; - goto put_src_fail; - } + err = -ENODEV; - /* for now the destination device needs to be a CAN device */ - if (gwj->dst_dev->type != ARPHRD_CAN) { - err = -ENODEV; - goto put_src_dst_fail; - } + /* ifindex == 0 is not allowed for job creation */ + if (!gwj->ccgw.src_idx || !gwj->ccgw.dst_idx) + goto out; - gwj->handled_frames = 0; - gwj->dropped_frames = 0; - gwj->flags = 0; + gwj->src.dev = dev_get_by_index(&init_net, gwj->ccgw.src_idx); - if (r->can_txflags & CAN_GW_TXFLAGS_ECHO) - gwj->flags |= CAN_TX_ECHO; + if (!gwj->src.dev) + goto out; - if (r->can_txflags & CAN_GW_TXFLAGS_SRC_TSTAMP) - gwj->flags |= CAN_TX_SRC_TSTAMP; + /* check for CAN netdev not using header_ops - see gw_rcv() */ + if (gwj->src.dev->type != ARPHRD_CAN || gwj->src.dev->header_ops) + goto put_src_out; - err = can_can_parse_attr(nlh, &gwj->ccgw); - if (err < 0) - goto put_src_dst_fail; + gwj->dst.dev = dev_get_by_index(&init_net, gwj->ccgw.dst_idx); - spin_lock(&can_gw_list_lock); + if (!gwj->dst.dev) + goto put_src_out; - err = can_gw_register_filter(gwj); - if (!err) - hlist_add_head_rcu(&gwj->list, &can_gw_list); + /* check for CAN netdev not using header_ops - see gw_rcv() */ + if (gwj->dst.dev->type != ARPHRD_CAN || gwj->dst.dev->header_ops) + goto put_src_dst_out; - spin_unlock(&can_gw_list_lock); - - dev_put(gwj->src_dev); - dev_put(gwj->dst_dev); + ASSERT_RTNL(); - if (err) - goto fail; + err = cgw_register_filter(gwj); + if (!err) + hlist_add_head_rcu(&gwj->list, &cgw_list); - return 0; +put_src_dst_out: + dev_put(gwj->dst.dev); +put_src_out: + dev_put(gwj->src.dev); +out: + if (err) + kmem_cache_free(cgw_cache, gwj); -put_src_dst_fail: - dev_put(gwj->dst_dev); -put_src_fail: - dev_put(gwj->src_dev); -fail: - kmem_cache_free(gw_cache, gwj); return err; } -static int gw_remove_job(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) +static void cgw_remove_all_jobs(void) +{ + struct cgw_job *gwj = NULL; + struct hlist_node *n, *nx; + + ASSERT_RTNL(); + + hlist_for_each_entry_safe(gwj, n, nx, &cgw_list, list) { + hlist_del(&gwj->list); + cgw_unregister_filter(gwj); + kfree(gwj); + } +} + +static int cgw_remove_job(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) { - struct gw_job *gwj = NULL; + struct cgw_job *gwj = NULL; struct hlist_node *n, *nx; struct rtcanmsg *r; + struct cf_mod mod; struct can_can_gw ccgw; - u32 flags = 0; int err = 0; if (nlmsg_len(nlh) < sizeof(*r)) - return -EINVAL; - - r = nlmsg_data(nlh); - if (r->can_family != AF_CAN) - return -EPFNOSUPPORT; + return -EINVAL; - if (r->can_txflags & CAN_GW_TXFLAGS_ECHO) - flags |= CAN_TX_ECHO; + r = nlmsg_data(nlh); + if (r->can_family != AF_CAN) + return -EPFNOSUPPORT; - if (r->can_txflags & CAN_GW_TXFLAGS_SRC_TSTAMP) - flags |= CAN_TX_SRC_TSTAMP; + /* so far we only support CAN -> CAN routings */ + if (r->gwtype != CGW_TYPE_CAN_CAN) + return -EINVAL; - err = can_can_parse_attr(nlh, &ccgw); + err = cgw_parse_attr(nlh, &mod, CGW_TYPE_CAN_CAN, &ccgw); if (err < 0) return err; + /* two interface indices both set to 0 => remove all entries */ + if (!ccgw.src_idx && !ccgw.dst_idx) { + cgw_remove_all_jobs(); + return 0; + } + err = -EINVAL; - spin_lock(&can_gw_list_lock); + ASSERT_RTNL(); /* remove only the first matching entry */ - hlist_for_each_entry_safe(gwj, n, nx, &can_gw_list, list) { + hlist_for_each_entry_safe(gwj, n, nx, &cgw_list, list) { - if (gwj->dst_dev->ifindex != r->dst_ifindex) + if (gwj->flags != r->flags) continue; - if (gwj->src_dev->ifindex != r->src_ifindex) - continue; - - if (gwj->flags != flags) + if (memcmp(&gwj->mod, &mod, sizeof(mod))) continue; + /* if (r->gwtype == CGW_TYPE_CAN_CAN) - is made sure here */ if (memcmp(&gwj->ccgw, &ccgw, sizeof(ccgw))) continue; hlist_del(&gwj->list); - can_gw_unregister_filter(gwj); + cgw_unregister_filter(gwj); kfree(gwj); err = 0; break; } - spin_unlock(&can_gw_list_lock); - return err; } -static __init int gw_module_init(void) +static __init int cgw_module_init(void) { printk(banner); - gw_cache = kmem_cache_create("can_gw", sizeof(struct gw_job), + cgw_cache = kmem_cache_create("can_gw", sizeof(struct cgw_job), 0, 0, NULL); - if (!gw_cache) + if (!cgw_cache) return -ENOMEM; /* set notifier */ - notifier.notifier_call = gw_notifier; + notifier.notifier_call = cgw_notifier; register_netdevice_notifier(¬ifier); - if (__rtnl_register(PF_CAN, RTM_GETROUTE, NULL, gw_dump_jobs)) { + if (__rtnl_register(PF_CAN, RTM_GETROUTE, NULL, cgw_dump_jobs)) { unregister_netdevice_notifier(¬ifier); - kmem_cache_destroy(gw_cache); + kmem_cache_destroy(cgw_cache); return -ENOBUFS; } /* Only the first call to __rtnl_register can fail */ - __rtnl_register(PF_CAN, RTM_NEWROUTE, gw_create_job, NULL); - __rtnl_register(PF_CAN, RTM_DELROUTE, gw_remove_job, NULL); + __rtnl_register(PF_CAN, RTM_NEWROUTE, cgw_create_job, NULL); + __rtnl_register(PF_CAN, RTM_DELROUTE, cgw_remove_job, NULL); return 0; } -static __exit void gw_module_exit(void) +static __exit void cgw_module_exit(void) { - struct gw_job *gwj = NULL; - struct hlist_node *n, *nx; - rtnl_unregister_all(PF_CAN); unregister_netdevice_notifier(¬ifier); - spin_lock(&can_gw_list_lock); - - hlist_for_each_entry_safe(gwj, n, nx, &can_gw_list, list) { - hlist_del(&gwj->list); - can_gw_unregister_filter(gwj); - kfree(gwj); - } - - spin_unlock(&can_gw_list_lock); + rtnl_lock(); + cgw_remove_all_jobs(); + rtnl_unlock(); rcu_barrier(); /* Wait for completion of call_rcu()'s */ - kmem_cache_destroy(gw_cache); + kmem_cache_destroy(cgw_cache); } -module_init(gw_module_init); -module_exit(gw_module_exit); +module_init(cgw_module_init); +module_exit(cgw_module_exit);