diff options
Diffstat (limited to 'net/netfilter/xt_DSCP.c')
-rw-r--r-- | net/netfilter/xt_DSCP.c | 167 |
1 files changed, 138 insertions, 29 deletions
diff --git a/net/netfilter/xt_DSCP.c b/net/netfilter/xt_DSCP.c index 6322a93..97efd74 100644 --- a/net/netfilter/xt_DSCP.c +++ b/net/netfilter/xt_DSCP.c @@ -18,19 +18,20 @@ #include <linux/netfilter/x_tables.h> #include <linux/netfilter/xt_DSCP.h> +#include <linux/netfilter_ipv4/ipt_TOS.h> MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>"); -MODULE_DESCRIPTION("x_tables DSCP modification module"); +MODULE_DESCRIPTION("Xtables: DSCP/TOS field modification"); MODULE_LICENSE("GPL"); MODULE_ALIAS("ipt_DSCP"); MODULE_ALIAS("ip6t_DSCP"); +MODULE_ALIAS("ipt_TOS"); +MODULE_ALIAS("ip6t_TOS"); -static unsigned int target(struct sk_buff *skb, - const struct net_device *in, - const struct net_device *out, - unsigned int hooknum, - const struct xt_target *target, - const void *targinfo) +static unsigned int +dscp_tg(struct sk_buff *skb, const struct net_device *in, + const struct net_device *out, unsigned int hooknum, + const struct xt_target *target, const void *targinfo) { const struct xt_DSCP_info *dinfo = targinfo; u_int8_t dscp = ipv4_get_dsfield(ip_hdr(skb)) >> XT_DSCP_SHIFT; @@ -46,12 +47,10 @@ static unsigned int target(struct sk_buff *skb, return XT_CONTINUE; } -static unsigned int target6(struct sk_buff *skb, - const struct net_device *in, - const struct net_device *out, - unsigned int hooknum, - const struct xt_target *target, - const void *targinfo) +static unsigned int +dscp_tg6(struct sk_buff *skb, const struct net_device *in, + const struct net_device *out, unsigned int hooknum, + const struct xt_target *target, const void *targinfo) { const struct xt_DSCP_info *dinfo = targinfo; u_int8_t dscp = ipv6_get_dsfield(ipv6_hdr(skb)) >> XT_DSCP_SHIFT; @@ -66,11 +65,10 @@ static unsigned int target6(struct sk_buff *skb, return XT_CONTINUE; } -static bool checkentry(const char *tablename, - const void *e_void, - const struct xt_target *target, - void *targinfo, - unsigned int hook_mask) +static bool +dscp_tg_check(const char *tablename, const void *e_void, + const struct xt_target *target, void *targinfo, + unsigned int hook_mask) { const u_int8_t dscp = ((struct xt_DSCP_info *)targinfo)->dscp; @@ -81,12 +79,95 @@ static bool checkentry(const char *tablename, return true; } -static struct xt_target xt_dscp_target[] __read_mostly = { +static unsigned int +tos_tg_v0(struct sk_buff *skb, const struct net_device *in, + const struct net_device *out, unsigned int hooknum, + const struct xt_target *target, const void *targinfo) +{ + const struct ipt_tos_target_info *info = targinfo; + struct iphdr *iph = ip_hdr(skb); + u_int8_t oldtos; + + if ((iph->tos & IPTOS_TOS_MASK) != info->tos) { + if (!skb_make_writable(skb, sizeof(struct iphdr))) + return NF_DROP; + + iph = ip_hdr(skb); + oldtos = iph->tos; + iph->tos = (iph->tos & IPTOS_PREC_MASK) | info->tos; + csum_replace2(&iph->check, htons(oldtos), htons(iph->tos)); + } + + return XT_CONTINUE; +} + +static bool +tos_tg_check_v0(const char *tablename, const void *e_void, + const struct xt_target *target, void *targinfo, + unsigned int hook_mask) +{ + const u_int8_t tos = ((struct ipt_tos_target_info *)targinfo)->tos; + + if (tos != IPTOS_LOWDELAY && tos != IPTOS_THROUGHPUT && + tos != IPTOS_RELIABILITY && tos != IPTOS_MINCOST && + tos != IPTOS_NORMALSVC) { + printk(KERN_WARNING "TOS: bad tos value %#x\n", tos); + return false; + } + + return true; +} + +static unsigned int +tos_tg(struct sk_buff *skb, const struct net_device *in, + const struct net_device *out, unsigned int hooknum, + const struct xt_target *target, const void *targinfo) +{ + const struct xt_tos_target_info *info = targinfo; + struct iphdr *iph = ip_hdr(skb); + u_int8_t orig, nv; + + orig = ipv4_get_dsfield(iph); + nv = (orig & ~info->tos_mask) ^ info->tos_value; + + if (orig != nv) { + if (!skb_make_writable(skb, sizeof(struct iphdr))) + return NF_DROP; + iph = ip_hdr(skb); + ipv4_change_dsfield(iph, 0, nv); + } + + return XT_CONTINUE; +} + +static unsigned int +tos_tg6(struct sk_buff *skb, const struct net_device *in, + const struct net_device *out, unsigned int hooknum, + const struct xt_target *target, const void *targinfo) +{ + const struct xt_tos_target_info *info = targinfo; + struct ipv6hdr *iph = ipv6_hdr(skb); + u_int8_t orig, nv; + + orig = ipv6_get_dsfield(iph); + nv = (orig & info->tos_mask) ^ info->tos_value; + + if (orig != nv) { + if (!skb_make_writable(skb, sizeof(struct iphdr))) + return NF_DROP; + iph = ipv6_hdr(skb); + ipv6_change_dsfield(iph, 0, nv); + } + + return XT_CONTINUE; +} + +static struct xt_target dscp_tg_reg[] __read_mostly = { { .name = "DSCP", .family = AF_INET, - .checkentry = checkentry, - .target = target, + .checkentry = dscp_tg_check, + .target = dscp_tg, .targetsize = sizeof(struct xt_DSCP_info), .table = "mangle", .me = THIS_MODULE, @@ -94,23 +175,51 @@ static struct xt_target xt_dscp_target[] __read_mostly = { { .name = "DSCP", .family = AF_INET6, - .checkentry = checkentry, - .target = target6, + .checkentry = dscp_tg_check, + .target = dscp_tg6, .targetsize = sizeof(struct xt_DSCP_info), .table = "mangle", .me = THIS_MODULE, }, + { + .name = "TOS", + .revision = 0, + .family = AF_INET, + .table = "mangle", + .target = tos_tg_v0, + .targetsize = sizeof(struct ipt_tos_target_info), + .checkentry = tos_tg_check_v0, + .me = THIS_MODULE, + }, + { + .name = "TOS", + .revision = 1, + .family = AF_INET, + .table = "mangle", + .target = tos_tg, + .targetsize = sizeof(struct xt_tos_target_info), + .me = THIS_MODULE, + }, + { + .name = "TOS", + .revision = 1, + .family = AF_INET6, + .table = "mangle", + .target = tos_tg6, + .targetsize = sizeof(struct xt_tos_target_info), + .me = THIS_MODULE, + }, }; -static int __init xt_dscp_target_init(void) +static int __init dscp_tg_init(void) { - return xt_register_targets(xt_dscp_target, ARRAY_SIZE(xt_dscp_target)); + return xt_register_targets(dscp_tg_reg, ARRAY_SIZE(dscp_tg_reg)); } -static void __exit xt_dscp_target_fini(void) +static void __exit dscp_tg_exit(void) { - xt_unregister_targets(xt_dscp_target, ARRAY_SIZE(xt_dscp_target)); + xt_unregister_targets(dscp_tg_reg, ARRAY_SIZE(dscp_tg_reg)); } -module_init(xt_dscp_target_init); -module_exit(xt_dscp_target_fini); +module_init(dscp_tg_init); +module_exit(dscp_tg_exit); |