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Diffstat (limited to 'net/netfilter/xt_TCPMSS.c')
-rw-r--r--net/netfilter/xt_TCPMSS.c94
1 files changed, 44 insertions, 50 deletions
diff --git a/net/netfilter/xt_TCPMSS.c b/net/netfilter/xt_TCPMSS.c
index 8e76d1f52fb..60e3767cc71 100644
--- a/net/netfilter/xt_TCPMSS.c
+++ b/net/netfilter/xt_TCPMSS.c
@@ -24,7 +24,7 @@
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Marc Boucher <marc@mbsi.ca>");
-MODULE_DESCRIPTION("x_tables TCP MSS modification module");
+MODULE_DESCRIPTION("Xtables: TCP Maximum Segment Size (MSS) adjustment");
MODULE_ALIAS("ipt_TCPMSS");
MODULE_ALIAS("ip6t_TCPMSS");
@@ -88,15 +88,19 @@ tcpmss_mangle_packet(struct sk_buff *skb,
oldmss = (opt[i+2] << 8) | opt[i+3];
- if (info->mss == XT_TCPMSS_CLAMP_PMTU &&
- oldmss <= newmss)
+ /* Never increase MSS, even when setting it, as
+ * doing so results in problems for hosts that rely
+ * on MSS being set correctly.
+ */
+ if (oldmss <= newmss)
return 0;
opt[i+2] = (newmss & 0xff00) >> 8;
opt[i+3] = newmss & 0x00ff;
- nf_proto_csum_replace2(&tcph->check, skb,
- htons(oldmss), htons(newmss), 0);
+ inet_proto_csum_replace2(&tcph->check, skb,
+ htons(oldmss), htons(newmss),
+ 0);
return 0;
}
}
@@ -117,29 +121,26 @@ tcpmss_mangle_packet(struct sk_buff *skb,
opt = (u_int8_t *)tcph + sizeof(struct tcphdr);
memmove(opt + TCPOLEN_MSS, opt, tcplen - sizeof(struct tcphdr));
- nf_proto_csum_replace2(&tcph->check, skb,
- htons(tcplen), htons(tcplen + TCPOLEN_MSS), 1);
+ inet_proto_csum_replace2(&tcph->check, skb,
+ htons(tcplen), htons(tcplen + TCPOLEN_MSS), 1);
opt[0] = TCPOPT_MSS;
opt[1] = TCPOLEN_MSS;
opt[2] = (newmss & 0xff00) >> 8;
opt[3] = newmss & 0x00ff;
- nf_proto_csum_replace4(&tcph->check, skb, 0, *((__be32 *)opt), 0);
+ inet_proto_csum_replace4(&tcph->check, skb, 0, *((__be32 *)opt), 0);
oldval = ((__be16 *)tcph)[6];
tcph->doff += TCPOLEN_MSS/4;
- nf_proto_csum_replace2(&tcph->check, skb,
- oldval, ((__be16 *)tcph)[6], 0);
+ inet_proto_csum_replace2(&tcph->check, skb,
+ oldval, ((__be16 *)tcph)[6], 0);
return TCPOLEN_MSS;
}
static unsigned int
-xt_tcpmss_target4(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)
+tcpmss_tg4(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)
{
struct iphdr *iph = ip_hdr(skb);
__be16 newlen;
@@ -152,7 +153,7 @@ xt_tcpmss_target4(struct sk_buff *skb,
if (ret > 0) {
iph = ip_hdr(skb);
newlen = htons(ntohs(iph->tot_len) + ret);
- nf_csum_replace2(&iph->check, iph->tot_len, newlen);
+ csum_replace2(&iph->check, iph->tot_len, newlen);
iph->tot_len = newlen;
}
return XT_CONTINUE;
@@ -160,12 +161,9 @@ xt_tcpmss_target4(struct sk_buff *skb,
#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
static unsigned int
-xt_tcpmss_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)
+tcpmss_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)
{
struct ipv6hdr *ipv6h = ipv6_hdr(skb);
u8 nexthdr;
@@ -204,19 +202,17 @@ static inline bool find_syn_match(const struct xt_entry_match *m)
}
static bool
-xt_tcpmss_checkentry4(const char *tablename,
- const void *entry,
- const struct xt_target *target,
- void *targinfo,
- unsigned int hook_mask)
+tcpmss_tg4_check(const char *tablename, const void *entry,
+ const struct xt_target *target, void *targinfo,
+ unsigned int hook_mask)
{
const struct xt_tcpmss_info *info = targinfo;
const struct ipt_entry *e = entry;
if (info->mss == XT_TCPMSS_CLAMP_PMTU &&
- (hook_mask & ~((1 << NF_IP_FORWARD) |
- (1 << NF_IP_LOCAL_OUT) |
- (1 << NF_IP_POST_ROUTING))) != 0) {
+ (hook_mask & ~((1 << NF_INET_FORWARD) |
+ (1 << NF_INET_LOCAL_OUT) |
+ (1 << NF_INET_POST_ROUTING))) != 0) {
printk("xt_TCPMSS: path-MTU clamping only supported in "
"FORWARD, OUTPUT and POSTROUTING hooks\n");
return false;
@@ -229,19 +225,17 @@ xt_tcpmss_checkentry4(const char *tablename,
#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
static bool
-xt_tcpmss_checkentry6(const char *tablename,
- const void *entry,
- const struct xt_target *target,
- void *targinfo,
- unsigned int hook_mask)
+tcpmss_tg6_check(const char *tablename, const void *entry,
+ const struct xt_target *target, void *targinfo,
+ unsigned int hook_mask)
{
const struct xt_tcpmss_info *info = targinfo;
const struct ip6t_entry *e = entry;
if (info->mss == XT_TCPMSS_CLAMP_PMTU &&
- (hook_mask & ~((1 << NF_IP6_FORWARD) |
- (1 << NF_IP6_LOCAL_OUT) |
- (1 << NF_IP6_POST_ROUTING))) != 0) {
+ (hook_mask & ~((1 << NF_INET_FORWARD) |
+ (1 << NF_INET_LOCAL_OUT) |
+ (1 << NF_INET_POST_ROUTING))) != 0) {
printk("xt_TCPMSS: path-MTU clamping only supported in "
"FORWARD, OUTPUT and POSTROUTING hooks\n");
return false;
@@ -253,12 +247,12 @@ xt_tcpmss_checkentry6(const char *tablename,
}
#endif
-static struct xt_target xt_tcpmss_reg[] __read_mostly = {
+static struct xt_target tcpmss_tg_reg[] __read_mostly = {
{
.family = AF_INET,
.name = "TCPMSS",
- .checkentry = xt_tcpmss_checkentry4,
- .target = xt_tcpmss_target4,
+ .checkentry = tcpmss_tg4_check,
+ .target = tcpmss_tg4,
.targetsize = sizeof(struct xt_tcpmss_info),
.proto = IPPROTO_TCP,
.me = THIS_MODULE,
@@ -267,8 +261,8 @@ static struct xt_target xt_tcpmss_reg[] __read_mostly = {
{
.family = AF_INET6,
.name = "TCPMSS",
- .checkentry = xt_tcpmss_checkentry6,
- .target = xt_tcpmss_target6,
+ .checkentry = tcpmss_tg6_check,
+ .target = tcpmss_tg6,
.targetsize = sizeof(struct xt_tcpmss_info),
.proto = IPPROTO_TCP,
.me = THIS_MODULE,
@@ -276,15 +270,15 @@ static struct xt_target xt_tcpmss_reg[] __read_mostly = {
#endif
};
-static int __init xt_tcpmss_init(void)
+static int __init tcpmss_tg_init(void)
{
- return xt_register_targets(xt_tcpmss_reg, ARRAY_SIZE(xt_tcpmss_reg));
+ return xt_register_targets(tcpmss_tg_reg, ARRAY_SIZE(tcpmss_tg_reg));
}
-static void __exit xt_tcpmss_fini(void)
+static void __exit tcpmss_tg_exit(void)
{
- xt_unregister_targets(xt_tcpmss_reg, ARRAY_SIZE(xt_tcpmss_reg));
+ xt_unregister_targets(tcpmss_tg_reg, ARRAY_SIZE(tcpmss_tg_reg));
}
-module_init(xt_tcpmss_init);
-module_exit(xt_tcpmss_fini);
+module_init(tcpmss_tg_init);
+module_exit(tcpmss_tg_exit);
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-26 01:04:46 +0000