diff options
Diffstat (limited to 'kernel/linux')
| -rw-r--r-- | kernel/linux/include/linux/netfilter_bridge/ebt_stp.h | 46 | ||||
| -rw-r--r-- | kernel/linux/net/bridge/netfilter/ebt_stp.c | 191 |
2 files changed, 237 insertions, 0 deletions
diff --git a/kernel/linux/include/linux/netfilter_bridge/ebt_stp.h b/kernel/linux/include/linux/netfilter_bridge/ebt_stp.h new file mode 100644 index 0000000..e5fd678 --- /dev/null +++ b/kernel/linux/include/linux/netfilter_bridge/ebt_stp.h @@ -0,0 +1,46 @@ +#ifndef __LINUX_BRIDGE_EBT_STP_H +#define __LINUX_BRIDGE_EBT_STP_H + +#define EBT_STP_TYPE 0x0001 + +#define EBT_STP_FLAGS 0x0002 +#define EBT_STP_ROOTPRIO 0x0004 +#define EBT_STP_ROOTADDR 0x0008 +#define EBT_STP_ROOTCOST 0x0010 +#define EBT_STP_SENDERPRIO 0x0020 +#define EBT_STP_SENDERADDR 0x0040 +#define EBT_STP_PORT 0x0080 +#define EBT_STP_MSGAGE 0x0100 +#define EBT_STP_MAXAGE 0x0200 +#define EBT_STP_HELLOTIME 0x0400 +#define EBT_STP_FWDD 0x0800 + +#define EBT_STP_MASK 0x0fff +#define EBT_STP_CONFIG_MASK 0x0ffe + +#define EBT_STP_MATCH "stp" + +struct ebt_stp_config_info +{ + uint8_t flags; + uint16_t root_priol, root_priou; + char root_addr[6], root_addrmsk[6]; + uint32_t root_costl, root_costu; + uint16_t sender_priol, sender_priou; + char sender_addr[6], sender_addrmsk[6]; + uint16_t portl, portu; + uint16_t msg_agel, msg_ageu; + uint16_t max_agel, max_ageu; + uint16_t hello_timel, hello_timeu; + uint16_t forward_delayl, forward_delayu; +}; + +struct ebt_stp_info +{ + uint8_t type; + struct ebt_stp_config_info config; + uint16_t bitmask; + uint16_t invflags; +}; + +#endif diff --git a/kernel/linux/net/bridge/netfilter/ebt_stp.c b/kernel/linux/net/bridge/netfilter/ebt_stp.c new file mode 100644 index 0000000..fcea9d3 --- /dev/null +++ b/kernel/linux/net/bridge/netfilter/ebt_stp.c @@ -0,0 +1,191 @@ +/* + * ebt_stp + * + * Authors: + * Bart De Schuymer <bdschuym@pandora.be> + * Stephen Hemminger <shemminger@osdl.org> + * + * June, 2003 + */ + +#include <linux/netfilter_bridge/ebtables.h> +#include <linux/netfilter_bridge/ebt_stp.h> +#include <linux/module.h> + +#define BPDU_TYPE_CONFIG 0 +#define BPDU_TYPE_TCN 0x80 + +struct stp_header { + uint8_t dsap; + uint8_t ssap; + uint8_t ctrl; + uint8_t pid; + uint8_t vers; + uint8_t type; +}; + +struct stp_config_pdu { + uint8_t flags; + uint8_t root[8]; + uint8_t root_cost[4]; + uint8_t sender[8]; + uint8_t port[2]; + uint8_t msg_age[2]; + uint8_t max_age[2]; + uint8_t hello_time[2]; + uint8_t forward_delay[2]; +}; + +#define NR16(p) (p[0] << 8 | p[1]) +#define NR32(p) ((p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3]) + +static int ebt_filter_config(struct ebt_stp_info *info, + struct stp_config_pdu *stpc) +{ + struct ebt_stp_config_info *c; + uint16_t v16; + uint32_t v32; + int verdict, i; + + c = &info->config; + if ((info->bitmask & EBT_STP_FLAGS) && + FWINV(c->flags != stpc->flags, EBT_STP_FLAGS)) + return EBT_NOMATCH; + if (info->bitmask & EBT_STP_ROOTPRIO) { + v16 = NR16(stpc->root); + if (FWINV(v16 < c->root_priol || + v16 > c->root_priou, EBT_STP_ROOTPRIO)) + return EBT_NOMATCH; + } + if (info->bitmask & EBT_STP_ROOTADDR) { + verdict = 0; + for (i = 0; i < 6; i++) + verdict |= (stpc->root[2+i] ^ c->root_addr[i]) & + c->root_addrmsk[i]; + if (FWINV(verdict != 0, EBT_STP_ROOTADDR)) + return EBT_NOMATCH; + } + if (info->bitmask & EBT_STP_ROOTCOST) { + v32 = NR32(stpc->root_cost); + if (FWINV(v32 < c->root_costl || + v32 > c->root_costu, EBT_STP_ROOTCOST)) + return EBT_NOMATCH; + } + if (info->bitmask & EBT_STP_SENDERPRIO) { + v16 = NR16(stpc->sender); + if (FWINV(v16 < c->sender_priol || + v16 > c->sender_priou, EBT_STP_SENDERPRIO)) + return EBT_NOMATCH; + } + if (info->bitmask & EBT_STP_SENDERADDR) { + verdict = 0; + for (i = 0; i < 6; i++) + verdict |= (stpc->sender[2+i] ^ c->sender_addr[i]) & + c->sender_addrmsk[i]; + if (FWINV(verdict != 0, EBT_STP_SENDERADDR)) + return EBT_NOMATCH; + } + if (info->bitmask & EBT_STP_PORT) { + v16 = NR16(stpc->port); + if (FWINV(v16 < c->portl || + v16 > c->portu, EBT_STP_PORT)) + return EBT_NOMATCH; + } + if (info->bitmask & EBT_STP_MSGAGE) { + v16 = NR16(stpc->msg_age); + if (FWINV(v16 < c->msg_agel || + v16 > c->msg_ageu, EBT_STP_MSGAGE)) + return EBT_NOMATCH; + } + if (info->bitmask & EBT_STP_MAXAGE) { + v16 = NR16(stpc->max_age); + if (FWINV(v16 < c->max_agel || + v16 > c->max_ageu, EBT_STP_MAXAGE)) + return EBT_NOMATCH; + } + if (info->bitmask & EBT_STP_HELLOTIME) { + v16 = NR16(stpc->hello_time); + if (FWINV(v16 < c->hello_timel || + v16 > c->hello_timeu, EBT_STP_HELLOTIME)) + return EBT_NOMATCH; + } + if (info->bitmask & EBT_STP_FWDD) { + v16 = NR16(stpc->forward_delay); + if (FWINV(v16 < c->forward_delayl || + v16 > c->forward_delayu, EBT_STP_FWDD)) + return EBT_NOMATCH; + } + return EBT_MATCH; +} + +static int ebt_filter_stp(const struct sk_buff *skb, const struct net_device *in, + const struct net_device *out, const void *data, unsigned int datalen) +{ + struct ebt_stp_info *info = (struct ebt_stp_info *)data; + struct stp_header stph; + uint8_t header[6] = {0x42, 0x42, 0x03, 0x00, 0x00, 0x00}; + if (skb_copy_bits(skb, 0, &stph, sizeof(stph))) + return EBT_NOMATCH; + + /* The stp code only considers these */ + if (memcmp(&stph, header, sizeof(header))) + return EBT_NOMATCH; + + if (info->bitmask & EBT_STP_TYPE + && FWINV(info->type != stph.type, EBT_STP_TYPE)) + return EBT_NOMATCH; + + if (stph.type == BPDU_TYPE_CONFIG && + info->bitmask & EBT_STP_CONFIG_MASK) { + struct stp_config_pdu stpc; + + if (skb_copy_bits(skb, sizeof(stph), &stpc, sizeof(stpc))) + return EBT_NOMATCH; + return ebt_filter_config(info, &stpc); + } + return EBT_MATCH; +} + +static int ebt_stp_check(const char *tablename, unsigned int hookmask, + const struct ebt_entry *e, void *data, unsigned int datalen) +{ + struct ebt_stp_info *info = (struct ebt_stp_info *)data; + int len = EBT_ALIGN(sizeof(struct ebt_stp_info)); + uint8_t bridge_ula[6] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 }; + uint8_t msk[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; + + if (info->bitmask & ~EBT_STP_MASK || info->invflags & ~EBT_STP_MASK || + !(info->bitmask & EBT_STP_MASK)) + return -EINVAL; + if (datalen != len) + return -EINVAL; + /* Make sure the match only receives stp frames */ + if (memcmp(e->destmac, bridge_ula, ETH_ALEN) || + memcmp(e->destmsk, msk, ETH_ALEN) || !(e->bitmask & EBT_DESTMAC)) + return -EINVAL; + + return 0; +} + +static struct ebt_match filter_stp = +{ + .name = EBT_STP_MATCH, + .match = ebt_filter_stp, + .check = ebt_stp_check, + .me = THIS_MODULE, +}; + +static int __init init(void) +{ + return ebt_register_match(&filter_stp); +} + +static void __exit fini(void) +{ + ebt_unregister_match(&filter_stp); +} + +module_init(init); +module_exit(fini); +EXPORT_NO_SYMBOLS; +MODULE_LICENSE("GPL"); |