anonfunc/xtables-addons
1
0
Fork 0
mirror of git://git.code.sf.net/p/xtables-addons/xtables-addons synced 2025-09-07 05:05:12 +02:00
Code Issues Releases Wiki Activity

xt_ECHO: calculate UDP checksum

Browse Source
This commit is contained in:
Jan Engelhardt
2011-09-25 14:20:07 +02:00
parent 30d227135b
commit 434dea2b53
2 changed files with 15 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
doc/changelog.txt
View File

@@ -3,6 +3,8 @@ HEAD
==== ====
Fixes: Fixes:
- xt_ECHO: fix kernel warning about RTAX_HOPLIMIT being used - xt_ECHO: fix kernel warning about RTAX_HOPLIMIT being used
Changes:
- xt_ECHO: now calculates UDP checksum
v1.39 (2011-09-21) v1.39 (2011-09-21)

14
extensions/xt_ECHO.c
View File

@@ -70,13 +70,25 @@ echo_tg4(struct sk_buff **poldskb, const struct xt_action_param *par)
newudp->source = oldudp->dest; newudp->source = oldudp->dest;
newudp->dest = oldudp->source; newudp->dest = oldudp->source;
newudp->len = oldudp->len; newudp->len = oldudp->len;
newudp->check = 0;
data_len = htons(oldudp->len) - sizeof(*oldudp); data_len = htons(oldudp->len) - sizeof(*oldudp);
payload = skb_header_pointer(oldskb, par->thoff + payload = skb_header_pointer(oldskb, par->thoff +
sizeof(*oldudp), data_len, NULL); sizeof(*oldudp), data_len, NULL);
memcpy(skb_put(newskb, data_len), payload, data_len); memcpy(skb_put(newskb, data_len), payload, data_len);
#if 0
/*
* Since no fields are modified (we just swapped things around),
* this works too in our specific echo case.
*/
newudp->check = oldudp->check;
#else
newudp->check = 0;
newudp->check = csum_tcpudp_magic(newip->saddr, newip->daddr,
ntohs(newudp->len), IPPROTO_UDP,
csum_partial(newudp, ntohs(newudp->len), 0));
#endif
/* ip_route_me_harder expects the skb's dst to be set */ /* ip_route_me_harder expects the skb's dst to be set */
skb_dst_set(newskb, dst_clone(skb_dst(oldskb))); skb_dst_set(newskb, dst_clone(skb_dst(oldskb)));