diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/ipv4/netfilter/ipt_DSCP.c |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'net/ipv4/netfilter/ipt_DSCP.c')
-rw-r--r-- | net/ipv4/netfilter/ipt_DSCP.c | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/net/ipv4/netfilter/ipt_DSCP.c b/net/ipv4/netfilter/ipt_DSCP.c new file mode 100644 index 00000000000..3ea4509099f --- /dev/null +++ b/net/ipv4/netfilter/ipt_DSCP.c @@ -0,0 +1,106 @@ +/* iptables module for setting the IPv4 DSCP field, Version 1.8 + * + * (C) 2002 by Harald Welte <laforge@netfilter.org> + * based on ipt_FTOS.c (C) 2000 by Matthew G. Marsh <mgm@paktronix.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * See RFC2474 for a description of the DSCP field within the IP Header. + * + * ipt_DSCP.c,v 1.8 2002/08/06 18:41:57 laforge Exp +*/ + +#include <linux/module.h> +#include <linux/skbuff.h> +#include <linux/ip.h> +#include <net/checksum.h> + +#include <linux/netfilter_ipv4/ip_tables.h> +#include <linux/netfilter_ipv4/ipt_DSCP.h> + +MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>"); +MODULE_DESCRIPTION("iptables DSCP modification module"); +MODULE_LICENSE("GPL"); + +static unsigned int +target(struct sk_buff **pskb, + const struct net_device *in, + const struct net_device *out, + unsigned int hooknum, + const void *targinfo, + void *userinfo) +{ + const struct ipt_DSCP_info *dinfo = targinfo; + u_int8_t sh_dscp = ((dinfo->dscp << IPT_DSCP_SHIFT) & IPT_DSCP_MASK); + + + if (((*pskb)->nh.iph->tos & IPT_DSCP_MASK) != sh_dscp) { + u_int16_t diffs[2]; + + if (!skb_ip_make_writable(pskb, sizeof(struct iphdr))) + return NF_DROP; + + diffs[0] = htons((*pskb)->nh.iph->tos) ^ 0xFFFF; + (*pskb)->nh.iph->tos = ((*pskb)->nh.iph->tos & ~IPT_DSCP_MASK) + | sh_dscp; + diffs[1] = htons((*pskb)->nh.iph->tos); + (*pskb)->nh.iph->check + = csum_fold(csum_partial((char *)diffs, + sizeof(diffs), + (*pskb)->nh.iph->check + ^ 0xFFFF)); + (*pskb)->nfcache |= NFC_ALTERED; + } + return IPT_CONTINUE; +} + +static int +checkentry(const char *tablename, + const struct ipt_entry *e, + void *targinfo, + unsigned int targinfosize, + unsigned int hook_mask) +{ + const u_int8_t dscp = ((struct ipt_DSCP_info *)targinfo)->dscp; + + if (targinfosize != IPT_ALIGN(sizeof(struct ipt_DSCP_info))) { + printk(KERN_WARNING "DSCP: targinfosize %u != %Zu\n", + targinfosize, + IPT_ALIGN(sizeof(struct ipt_DSCP_info))); + return 0; + } + + if (strcmp(tablename, "mangle") != 0) { + printk(KERN_WARNING "DSCP: can only be called from \"mangle\" table, not \"%s\"\n", tablename); + return 0; + } + + if ((dscp > IPT_DSCP_MAX)) { + printk(KERN_WARNING "DSCP: dscp %x out of range\n", dscp); + return 0; + } + + return 1; +} + +static struct ipt_target ipt_dscp_reg = { + .name = "DSCP", + .target = target, + .checkentry = checkentry, + .me = THIS_MODULE, +}; + +static int __init init(void) +{ + return ipt_register_target(&ipt_dscp_reg); +} + +static void __exit fini(void) +{ + ipt_unregister_target(&ipt_dscp_reg); +} + +module_init(init); +module_exit(fini); |