@@ -802,6 +802,51 @@ config NETFILTER_XT_SET
To compile it as a module, choose M here. If unsure, say N.
+config NETFILTER_XT_DSCP
+ tristate '"DSCP" and "TOS" target and match support'
+ depends on NETFILTER_ADVANCED
+ help
+ This option adds the "DSCP" target and "dscp" match.
+
+ Netfilter dscp matching which allows you to match against the
+ IPv4/IPv6 header DSCP field (differentiated services codepoint).
+ The target allows you to manipulate the IPv4/IPv6
+ header DSCP field (differentiated services codepoint).
+
+config NETFILTER_XT_HL
+ tristate '"HL" hoplimit target and match support'
+ depends on NETFILTER_ADVANCED
+ help
+ This option adds the "HL" target and "hl" match.
+
+ Netfilter hl matching allows you to match packets based on
+ the hoplimit in the IPv6 header, or the time-to-live field in
+ the IPv4 header of the packet.
+ The target allows you to change the hoplimit/time-to-live
+ value of the IP header.
+
+config NETFILTER_XT_RATEEST
+ tristate '"RATEEST" target and match support'
+ depends on NETFILTER_ADVANCED
+ help
+ This option adds the "RATEEST" target and "rateest" match.
+
+ Netfilter rateest matching allows you to match on the rate
+ estimated by the RATEEST target.
+ The target allows you to measure rates similar to TC estimators.
+
+config NETFILTER_XT_TCPMSS
+ tristate '"TCPMSS" target and match support'
+ depends on IPV6 || IPV6=n
+ default m if NETFILTER_ADVANCED=n
+ help
+ This option adds the "TCPMSS" target and "tcpmss" match.
+
+ Netfilter tcpmss matching allows you to examine the MSS value of
+ TCP SYN packets, which control the maximum packet size for that connection.
+ The target allows you to alter the MSS value of TCP SYN packets,
+ to control the maximum size for that connection.
+
# alphabetically ordered list of targets
comment "Xtables targets"
@@ -882,6 +927,7 @@ config NETFILTER_XT_TARGET_DSCP
tristate '"DSCP" and "TOS" target support'
depends on IP_NF_MANGLE || IP6_NF_MANGLE || NFT_COMPAT
depends on NETFILTER_ADVANCED
+ select NETFILTER_XT_DSCP
help
This option adds a `DSCP' target, which allows you to manipulate
the IPv4/IPv6 header DSCP field (differentiated services codepoint).
@@ -892,12 +938,17 @@ config NETFILTER_XT_TARGET_DSCP
the "mangle" table which alter the Type Of Service field of an IPv4
or the Priority field of an IPv6 packet, prior to routing.
+ This is a backwards-compat option for the user's convenience
+ (e.g. when running oldconfig). It selects
+ CONFIG_NETFILTER_XT_DSCP (combined dscp/DSCP module).
+
To compile it as a module, choose M here. If unsure, say N.
config NETFILTER_XT_TARGET_HL
tristate '"HL" hoplimit target support'
depends on IP_NF_MANGLE || IP6_NF_MANGLE || NFT_COMPAT
depends on NETFILTER_ADVANCED
+ select NETFILTER_XT_HL
help
This option adds the "HL" (for IPv6) and "TTL" (for IPv4)
targets, which enable the user to change the
@@ -909,6 +960,10 @@ config NETFILTER_XT_TARGET_HL
since you can easily create immortal packets that loop
forever on the network.
+ This is a backwards-compat option for the user's convenience
+ (e.g. when running oldconfig). It selects
+ CONFIG_NETFILTER_XT_HL (combined hl/HL module).
+
config NETFILTER_XT_TARGET_HMARK
tristate '"HMARK" target support'
depends on IP6_NF_IPTABLES || IP6_NF_IPTABLES=n
@@ -1029,11 +1084,16 @@ config NETFILTER_XT_TARGET_NOTRACK
config NETFILTER_XT_TARGET_RATEEST
tristate '"RATEEST" target support'
depends on NETFILTER_ADVANCED
+ select NETFILTER_XT_RATEEST
help
This option adds a `RATEEST' target, which allows to measure
rates similar to TC estimators. The `rateest' match can be
used to match on the measured rates.
+ This is a backwards-compat option for the user's convenience
+ (e.g. when running oldconfig). It selects
+ CONFIG_NETFILTER_XT_RATEEST (combined rateest/RATEEST module).
+
To compile it as a module, choose M here. If unsure, say N.
config NETFILTER_XT_TARGET_REDIRECT
@@ -1122,6 +1182,7 @@ config NETFILTER_XT_TARGET_TCPMSS
tristate '"TCPMSS" target support'
depends on IPV6 || IPV6=n
default m if NETFILTER_ADVANCED=n
+ select NETFILTER_XT_TCPMSS
help
This option adds a `TCPMSS' target, which allows you to alter the
MSS value of TCP SYN packets, to control the maximum size for that
@@ -1143,6 +1204,10 @@ config NETFILTER_XT_TARGET_TCPMSS
iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN \
-j TCPMSS --clamp-mss-to-pmtu
+ This is a backwards-compat option for the user's convenience
+ (e.g. when running oldconfig). It selects
+ CONFIG_NETFILTER_XT_TCPMSS (combined tcpmss/TCPMSS module).
+
To compile it as a module, choose M here. If unsure, say N.
config NETFILTER_XT_TARGET_TCPOPTSTRIP
@@ -1301,6 +1366,7 @@ config NETFILTER_XT_MATCH_DEVGROUP
config NETFILTER_XT_MATCH_DSCP
tristate '"dscp" and "tos" match support'
depends on NETFILTER_ADVANCED
+ select NETFILTER_XT_DSCP
help
This option adds a `DSCP' match, which allows you to match against
the IPv4/IPv6 header DSCP field (differentiated services codepoint).
@@ -1311,6 +1377,10 @@ config NETFILTER_XT_MATCH_DSCP
based on the Type Of Service fields of the IPv4 packet (which share
the same bits as DSCP).
+ This is a backwards-compat option for the user's convenience
+ (e.g. when running oldconfig). It selects
+ CONFIG_NETFILTER_XT_DSCP (combined dscp/DSCP module).
+
To compile it as a module, choose M here. If unsure, say N.
config NETFILTER_XT_MATCH_ECN
@@ -1359,11 +1429,16 @@ config NETFILTER_XT_MATCH_HELPER
config NETFILTER_XT_MATCH_HL
tristate '"hl" hoplimit/TTL match support'
depends on NETFILTER_ADVANCED
+ select NETFILTER_XT_HL
help
HL matching allows you to match packets based on the hoplimit
in the IPv6 header, or the time-to-live field in the IPv4
header of the packet.
+ This is a backwards-compat option for the user's convenience
+ (e.g. when running oldconfig). It selects
+ CONFIG_NETFILTER_XT_HL (combined hl/HL module).
+
config NETFILTER_XT_MATCH_IPCOMP
tristate '"ipcomp" match support'
depends on NETFILTER_ADVANCED
@@ -1533,6 +1608,10 @@ config NETFILTER_XT_MATCH_RATEEST
This option adds a `rateest' match, which allows to match on the
rate estimated by the RATEEST target.
+ This is a backwards-compat option for the user's convenience
+ (e.g. when running oldconfig). It selects
+ CONFIG_NETFILTER_XT_RATEEST (combined rateest/RATEEST module).
+
To compile it as a module, choose M here. If unsure, say N.
config NETFILTER_XT_MATCH_REALM
@@ -1625,11 +1704,16 @@ config NETFILTER_XT_MATCH_STRING
config NETFILTER_XT_MATCH_TCPMSS
tristate '"tcpmss" match support'
depends on NETFILTER_ADVANCED
+ select NETFILTER_XT_TCPMSS
help
This option adds a `tcpmss' match, which allows you to examine the
MSS value of TCP SYN packets, which control the maximum packet size
for that connection.
+ This is a backwards-compat option for the user's convenience
+ (e.g. when running oldconfig). It selects
+ CONFIG_NETFILTER_XT_TCPMSS (combined tcpmss/TCPMSS module).
+
To compile it as a module, choose M here. If unsure, say N.
config NETFILTER_XT_MATCH_TIME
@@ -160,6 +160,10 @@ obj-$(CONFIG_NETFILTER_XT_MARK) += xt_mark.o
obj-$(CONFIG_NETFILTER_XT_CONNMARK) += xt_connmark.o
obj-$(CONFIG_NETFILTER_XT_SET) += xt_set.o
obj-$(CONFIG_NETFILTER_XT_NAT) += xt_nat.o
+obj-$(CONFIG_NETFILTER_XT_DSCP) += xt_dscp.o
+obj-$(CONFIG_NETFILTER_XT_HL) += xt_hl.o
+obj-$(CONFIG_NETFILTER_XT_RATEEST) += xt_rateest.o
+obj-$(CONFIG_NETFILTER_XT_TCPMSS) += xt_tcpmss.o
# targets
obj-$(CONFIG_NETFILTER_XT_TARGET_AUDIT) += xt_AUDIT.o
@@ -167,20 +171,16 @@ obj-$(CONFIG_NETFILTER_XT_TARGET_CHECKSUM) += xt_CHECKSUM.o
obj-$(CONFIG_NETFILTER_XT_TARGET_CLASSIFY) += xt_CLASSIFY.o
obj-$(CONFIG_NETFILTER_XT_TARGET_CONNSECMARK) += xt_CONNSECMARK.o
obj-$(CONFIG_NETFILTER_XT_TARGET_CT) += xt_CT.o
-obj-$(CONFIG_NETFILTER_XT_TARGET_DSCP) += xt_DSCP.o
-obj-$(CONFIG_NETFILTER_XT_TARGET_HL) += xt_HL.o
obj-$(CONFIG_NETFILTER_XT_TARGET_HMARK) += xt_HMARK.o
obj-$(CONFIG_NETFILTER_XT_TARGET_LED) += xt_LED.o
obj-$(CONFIG_NETFILTER_XT_TARGET_LOG) += xt_LOG.o
obj-$(CONFIG_NETFILTER_XT_TARGET_NETMAP) += xt_NETMAP.o
obj-$(CONFIG_NETFILTER_XT_TARGET_NFLOG) += xt_NFLOG.o
obj-$(CONFIG_NETFILTER_XT_TARGET_NFQUEUE) += xt_NFQUEUE.o
-obj-$(CONFIG_NETFILTER_XT_TARGET_RATEEST) += xt_RATEEST.o
obj-$(CONFIG_NETFILTER_XT_TARGET_REDIRECT) += xt_REDIRECT.o
obj-$(CONFIG_NETFILTER_XT_TARGET_MASQUERADE) += xt_MASQUERADE.o
obj-$(CONFIG_NETFILTER_XT_TARGET_SECMARK) += xt_SECMARK.o
obj-$(CONFIG_NETFILTER_XT_TARGET_TPROXY) += xt_TPROXY.o
-obj-$(CONFIG_NETFILTER_XT_TARGET_TCPMSS) += xt_TCPMSS.o
obj-$(CONFIG_NETFILTER_XT_TARGET_TCPOPTSTRIP) += xt_TCPOPTSTRIP.o
obj-$(CONFIG_NETFILTER_XT_TARGET_TEE) += xt_TEE.o
obj-$(CONFIG_NETFILTER_XT_TARGET_TRACE) += xt_TRACE.o
@@ -198,12 +198,10 @@ obj-$(CONFIG_NETFILTER_XT_MATCH_CONNTRACK) += xt_conntrack.o
obj-$(CONFIG_NETFILTER_XT_MATCH_CPU) += xt_cpu.o
obj-$(CONFIG_NETFILTER_XT_MATCH_DCCP) += xt_dccp.o
obj-$(CONFIG_NETFILTER_XT_MATCH_DEVGROUP) += xt_devgroup.o
-obj-$(CONFIG_NETFILTER_XT_MATCH_DSCP) += xt_dscp.o
obj-$(CONFIG_NETFILTER_XT_MATCH_ECN) += xt_ecn.o
obj-$(CONFIG_NETFILTER_XT_MATCH_ESP) += xt_esp.o
obj-$(CONFIG_NETFILTER_XT_MATCH_HASHLIMIT) += xt_hashlimit.o
obj-$(CONFIG_NETFILTER_XT_MATCH_HELPER) += xt_helper.o
-obj-$(CONFIG_NETFILTER_XT_MATCH_HL) += xt_hl.o
obj-$(CONFIG_NETFILTER_XT_MATCH_IPCOMP) += xt_ipcomp.o
obj-$(CONFIG_NETFILTER_XT_MATCH_IPRANGE) += xt_iprange.o
obj-$(CONFIG_NETFILTER_XT_MATCH_IPVS) += xt_ipvs.o
@@ -220,7 +218,6 @@ obj-$(CONFIG_NETFILTER_XT_MATCH_PHYSDEV) += xt_physdev.o
obj-$(CONFIG_NETFILTER_XT_MATCH_PKTTYPE) += xt_pkttype.o
obj-$(CONFIG_NETFILTER_XT_MATCH_POLICY) += xt_policy.o
obj-$(CONFIG_NETFILTER_XT_MATCH_QUOTA) += xt_quota.o
-obj-$(CONFIG_NETFILTER_XT_MATCH_RATEEST) += xt_rateest.o
obj-$(CONFIG_NETFILTER_XT_MATCH_REALM) += xt_realm.o
obj-$(CONFIG_NETFILTER_XT_MATCH_RECENT) += xt_recent.o
obj-$(CONFIG_NETFILTER_XT_MATCH_SCTP) += xt_sctp.o
@@ -228,7 +225,6 @@ obj-$(CONFIG_NETFILTER_XT_MATCH_SOCKET) += xt_socket.o
obj-$(CONFIG_NETFILTER_XT_MATCH_STATE) += xt_state.o
obj-$(CONFIG_NETFILTER_XT_MATCH_STATISTIC) += xt_statistic.o
obj-$(CONFIG_NETFILTER_XT_MATCH_STRING) += xt_string.o
-obj-$(CONFIG_NETFILTER_XT_MATCH_TCPMSS) += xt_tcpmss.o
obj-$(CONFIG_NETFILTER_XT_MATCH_TIME) += xt_time.o
obj-$(CONFIG_NETFILTER_XT_MATCH_U32) += xt_u32.o
deleted file mode 100644
@@ -1,161 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/* x_tables module for setting the IPv4/IPv6 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>
- *
- * See RFC2474 for a description of the DSCP field within the IP Header.
-*/
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-#include <linux/module.h>
-#include <linux/skbuff.h>
-#include <linux/ip.h>
-#include <linux/ipv6.h>
-#include <net/dsfield.h>
-
-#include <linux/netfilter/x_tables.h>
-#include <linux/netfilter/xt_dscp.h>
-
-MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
-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");
-
-#define XT_DSCP_ECN_MASK 3u
-
-static unsigned int
-dscp_tg(struct sk_buff *skb, const struct xt_action_param *par)
-{
- const struct xt_DSCP_info *dinfo = par->targinfo;
- u_int8_t dscp = ipv4_get_dsfield(ip_hdr(skb)) >> XT_DSCP_SHIFT;
-
- if (dscp != dinfo->dscp) {
- if (skb_ensure_writable(skb, sizeof(struct iphdr)))
- return NF_DROP;
-
- ipv4_change_dsfield(ip_hdr(skb), XT_DSCP_ECN_MASK,
- dinfo->dscp << XT_DSCP_SHIFT);
-
- }
- return XT_CONTINUE;
-}
-
-static unsigned int
-dscp_tg6(struct sk_buff *skb, const struct xt_action_param *par)
-{
- const struct xt_DSCP_info *dinfo = par->targinfo;
- u_int8_t dscp = ipv6_get_dsfield(ipv6_hdr(skb)) >> XT_DSCP_SHIFT;
-
- if (dscp != dinfo->dscp) {
- if (skb_ensure_writable(skb, sizeof(struct ipv6hdr)))
- return NF_DROP;
-
- ipv6_change_dsfield(ipv6_hdr(skb), XT_DSCP_ECN_MASK,
- dinfo->dscp << XT_DSCP_SHIFT);
- }
- return XT_CONTINUE;
-}
-
-static int dscp_tg_check(const struct xt_tgchk_param *par)
-{
- const struct xt_DSCP_info *info = par->targinfo;
-
- if (info->dscp > XT_DSCP_MAX)
- return -EDOM;
- return 0;
-}
-
-static unsigned int
-tos_tg(struct sk_buff *skb, const struct xt_action_param *par)
-{
- const struct xt_tos_target_info *info = par->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_ensure_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 xt_action_param *par)
-{
- const struct xt_tos_target_info *info = par->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_ensure_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 = NFPROTO_IPV4,
- .checkentry = dscp_tg_check,
- .target = dscp_tg,
- .targetsize = sizeof(struct xt_DSCP_info),
- .table = "mangle",
- .me = THIS_MODULE,
- },
- {
- .name = "DSCP",
- .family = NFPROTO_IPV6,
- .checkentry = dscp_tg_check,
- .target = dscp_tg6,
- .targetsize = sizeof(struct xt_DSCP_info),
- .table = "mangle",
- .me = THIS_MODULE,
- },
- {
- .name = "TOS",
- .revision = 1,
- .family = NFPROTO_IPV4,
- .table = "mangle",
- .target = tos_tg,
- .targetsize = sizeof(struct xt_tos_target_info),
- .me = THIS_MODULE,
- },
- {
- .name = "TOS",
- .revision = 1,
- .family = NFPROTO_IPV6,
- .table = "mangle",
- .target = tos_tg6,
- .targetsize = sizeof(struct xt_tos_target_info),
- .me = THIS_MODULE,
- },
-};
-
-static int __init dscp_tg_init(void)
-{
- return xt_register_targets(dscp_tg_reg, ARRAY_SIZE(dscp_tg_reg));
-}
-
-static void __exit dscp_tg_exit(void)
-{
- xt_unregister_targets(dscp_tg_reg, ARRAY_SIZE(dscp_tg_reg));
-}
-
-module_init(dscp_tg_init);
-module_exit(dscp_tg_exit);
deleted file mode 100644
@@ -1,159 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * TTL modification target for IP tables
- * (C) 2000,2005 by Harald Welte <laforge@netfilter.org>
- *
- * Hop Limit modification target for ip6tables
- * Maciej Soltysiak <solt@dns.toxicfilms.tv>
- */
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-#include <linux/module.h>
-#include <linux/skbuff.h>
-#include <linux/ip.h>
-#include <linux/ipv6.h>
-#include <net/checksum.h>
-
-#include <linux/netfilter/x_tables.h>
-#include <linux/netfilter_ipv4/ipt_ttl.h>
-#include <linux/netfilter_ipv6/ip6t_hl.h>
-
-MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
-MODULE_AUTHOR("Maciej Soltysiak <solt@dns.toxicfilms.tv>");
-MODULE_DESCRIPTION("Xtables: Hoplimit/TTL Limit field modification target");
-MODULE_LICENSE("GPL");
-
-static unsigned int
-ttl_tg(struct sk_buff *skb, const struct xt_action_param *par)
-{
- struct iphdr *iph;
- const struct ipt_TTL_info *info = par->targinfo;
- int new_ttl;
-
- if (skb_ensure_writable(skb, sizeof(*iph)))
- return NF_DROP;
-
- iph = ip_hdr(skb);
-
- switch (info->mode) {
- case IPT_TTL_SET:
- new_ttl = info->ttl;
- break;
- case IPT_TTL_INC:
- new_ttl = iph->ttl + info->ttl;
- if (new_ttl > 255)
- new_ttl = 255;
- break;
- case IPT_TTL_DEC:
- new_ttl = iph->ttl - info->ttl;
- if (new_ttl < 0)
- new_ttl = 0;
- break;
- default:
- new_ttl = iph->ttl;
- break;
- }
-
- if (new_ttl != iph->ttl) {
- csum_replace2(&iph->check, htons(iph->ttl << 8),
- htons(new_ttl << 8));
- iph->ttl = new_ttl;
- }
-
- return XT_CONTINUE;
-}
-
-static unsigned int
-hl_tg6(struct sk_buff *skb, const struct xt_action_param *par)
-{
- struct ipv6hdr *ip6h;
- const struct ip6t_HL_info *info = par->targinfo;
- int new_hl;
-
- if (skb_ensure_writable(skb, sizeof(*ip6h)))
- return NF_DROP;
-
- ip6h = ipv6_hdr(skb);
-
- switch (info->mode) {
- case IP6T_HL_SET:
- new_hl = info->hop_limit;
- break;
- case IP6T_HL_INC:
- new_hl = ip6h->hop_limit + info->hop_limit;
- if (new_hl > 255)
- new_hl = 255;
- break;
- case IP6T_HL_DEC:
- new_hl = ip6h->hop_limit - info->hop_limit;
- if (new_hl < 0)
- new_hl = 0;
- break;
- default:
- new_hl = ip6h->hop_limit;
- break;
- }
-
- ip6h->hop_limit = new_hl;
-
- return XT_CONTINUE;
-}
-
-static int ttl_tg_check(const struct xt_tgchk_param *par)
-{
- const struct ipt_TTL_info *info = par->targinfo;
-
- if (info->mode > IPT_TTL_MAXMODE)
- return -EINVAL;
- if (info->mode != IPT_TTL_SET && info->ttl == 0)
- return -EINVAL;
- return 0;
-}
-
-static int hl_tg6_check(const struct xt_tgchk_param *par)
-{
- const struct ip6t_HL_info *info = par->targinfo;
-
- if (info->mode > IP6T_HL_MAXMODE)
- return -EINVAL;
- if (info->mode != IP6T_HL_SET && info->hop_limit == 0)
- return -EINVAL;
- return 0;
-}
-
-static struct xt_target hl_tg_reg[] __read_mostly = {
- {
- .name = "TTL",
- .revision = 0,
- .family = NFPROTO_IPV4,
- .target = ttl_tg,
- .targetsize = sizeof(struct ipt_TTL_info),
- .table = "mangle",
- .checkentry = ttl_tg_check,
- .me = THIS_MODULE,
- },
- {
- .name = "HL",
- .revision = 0,
- .family = NFPROTO_IPV6,
- .target = hl_tg6,
- .targetsize = sizeof(struct ip6t_HL_info),
- .table = "mangle",
- .checkentry = hl_tg6_check,
- .me = THIS_MODULE,
- },
-};
-
-static int __init hl_tg_init(void)
-{
- return xt_register_targets(hl_tg_reg, ARRAY_SIZE(hl_tg_reg));
-}
-
-static void __exit hl_tg_exit(void)
-{
- xt_unregister_targets(hl_tg_reg, ARRAY_SIZE(hl_tg_reg));
-}
-
-module_init(hl_tg_init);
-module_exit(hl_tg_exit);
-MODULE_ALIAS("ipt_TTL");
-MODULE_ALIAS("ip6t_HL");
deleted file mode 100644
@@ -1,248 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * (C) 2007 Patrick McHardy <kaber@trash.net>
- */
-#include <linux/module.h>
-#include <linux/skbuff.h>
-#include <linux/gen_stats.h>
-#include <linux/jhash.h>
-#include <linux/rtnetlink.h>
-#include <linux/random.h>
-#include <linux/slab.h>
-#include <net/gen_stats.h>
-#include <net/netlink.h>
-#include <net/netns/generic.h>
-
-#include <linux/netfilter/x_tables.h>
-#include <linux/netfilter/xt_rateest.h>
-#include <net/netfilter/xt_rateest.h>
-
-#define RATEEST_HSIZE 16
-
-struct xt_rateest_net {
- struct mutex hash_lock;
- struct hlist_head hash[RATEEST_HSIZE];
-};
-
-static unsigned int xt_rateest_id;
-
-static unsigned int jhash_rnd __read_mostly;
-
-static unsigned int xt_rateest_hash(const char *name)
-{
- return jhash(name, sizeof_field(struct xt_rateest, name), jhash_rnd) &
- (RATEEST_HSIZE - 1);
-}
-
-static void xt_rateest_hash_insert(struct xt_rateest_net *xn,
- struct xt_rateest *est)
-{
- unsigned int h;
-
- h = xt_rateest_hash(est->name);
- hlist_add_head(&est->list, &xn->hash[h]);
-}
-
-static struct xt_rateest *__xt_rateest_lookup(struct xt_rateest_net *xn,
- const char *name)
-{
- struct xt_rateest *est;
- unsigned int h;
-
- h = xt_rateest_hash(name);
- hlist_for_each_entry(est, &xn->hash[h], list) {
- if (strcmp(est->name, name) == 0) {
- est->refcnt++;
- return est;
- }
- }
-
- return NULL;
-}
-
-struct xt_rateest *xt_rateest_lookup(struct net *net, const char *name)
-{
- struct xt_rateest_net *xn = net_generic(net, xt_rateest_id);
- struct xt_rateest *est;
-
- mutex_lock(&xn->hash_lock);
- est = __xt_rateest_lookup(xn, name);
- mutex_unlock(&xn->hash_lock);
- return est;
-}
-EXPORT_SYMBOL_GPL(xt_rateest_lookup);
-
-void xt_rateest_put(struct net *net, struct xt_rateest *est)
-{
- struct xt_rateest_net *xn = net_generic(net, xt_rateest_id);
-
- mutex_lock(&xn->hash_lock);
- if (--est->refcnt == 0) {
- hlist_del(&est->list);
- gen_kill_estimator(&est->rate_est);
- /*
- * gen_estimator est_timer() might access est->lock or bstats,
- * wait a RCU grace period before freeing 'est'
- */
- kfree_rcu(est, rcu);
- }
- mutex_unlock(&xn->hash_lock);
-}
-EXPORT_SYMBOL_GPL(xt_rateest_put);
-
-static unsigned int
-xt_rateest_tg(struct sk_buff *skb, const struct xt_action_param *par)
-{
- const struct xt_rateest_target_info *info = par->targinfo;
- struct gnet_stats_basic_sync *stats = &info->est->bstats;
-
- spin_lock_bh(&info->est->lock);
- u64_stats_add(&stats->bytes, skb->len);
- u64_stats_inc(&stats->packets);
- spin_unlock_bh(&info->est->lock);
-
- return XT_CONTINUE;
-}
-
-static int xt_rateest_tg_checkentry(const struct xt_tgchk_param *par)
-{
- struct xt_rateest_net *xn = net_generic(par->net, xt_rateest_id);
- struct xt_rateest_target_info *info = par->targinfo;
- struct xt_rateest *est;
- struct {
- struct nlattr opt;
- struct gnet_estimator est;
- } cfg;
- int ret;
-
- if (strnlen(info->name, sizeof(est->name)) >= sizeof(est->name))
- return -ENAMETOOLONG;
-
- net_get_random_once(&jhash_rnd, sizeof(jhash_rnd));
-
- mutex_lock(&xn->hash_lock);
- est = __xt_rateest_lookup(xn, info->name);
- if (est) {
- mutex_unlock(&xn->hash_lock);
- /*
- * If estimator parameters are specified, they must match the
- * existing estimator.
- */
- if ((!info->interval && !info->ewma_log) ||
- (info->interval != est->params.interval ||
- info->ewma_log != est->params.ewma_log)) {
- xt_rateest_put(par->net, est);
- return -EINVAL;
- }
- info->est = est;
- return 0;
- }
-
- ret = -ENOMEM;
- est = kzalloc(sizeof(*est), GFP_KERNEL);
- if (!est)
- goto err1;
-
- gnet_stats_basic_sync_init(&est->bstats);
- strscpy(est->name, info->name, sizeof(est->name));
- spin_lock_init(&est->lock);
- est->refcnt = 1;
- est->params.interval = info->interval;
- est->params.ewma_log = info->ewma_log;
-
- cfg.opt.nla_len = nla_attr_size(sizeof(cfg.est));
- cfg.opt.nla_type = TCA_STATS_RATE_EST;
- cfg.est.interval = info->interval;
- cfg.est.ewma_log = info->ewma_log;
-
- ret = gen_new_estimator(&est->bstats, NULL, &est->rate_est,
- &est->lock, NULL, &cfg.opt);
- if (ret < 0)
- goto err2;
-
- info->est = est;
- xt_rateest_hash_insert(xn, est);
- mutex_unlock(&xn->hash_lock);
- return 0;
-
-err2:
- kfree(est);
-err1:
- mutex_unlock(&xn->hash_lock);
- return ret;
-}
-
-static void xt_rateest_tg_destroy(const struct xt_tgdtor_param *par)
-{
- struct xt_rateest_target_info *info = par->targinfo;
-
- xt_rateest_put(par->net, info->est);
-}
-
-static struct xt_target xt_rateest_tg_reg[] __read_mostly = {
- {
- .name = "RATEEST",
- .revision = 0,
- .family = NFPROTO_IPV4,
- .target = xt_rateest_tg,
- .checkentry = xt_rateest_tg_checkentry,
- .destroy = xt_rateest_tg_destroy,
- .targetsize = sizeof(struct xt_rateest_target_info),
- .usersize = offsetof(struct xt_rateest_target_info, est),
- .me = THIS_MODULE,
- },
-#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
- {
- .name = "RATEEST",
- .revision = 0,
- .family = NFPROTO_IPV6,
- .target = xt_rateest_tg,
- .checkentry = xt_rateest_tg_checkentry,
- .destroy = xt_rateest_tg_destroy,
- .targetsize = sizeof(struct xt_rateest_target_info),
- .usersize = offsetof(struct xt_rateest_target_info, est),
- .me = THIS_MODULE,
- },
-#endif
-};
-
-static __net_init int xt_rateest_net_init(struct net *net)
-{
- struct xt_rateest_net *xn = net_generic(net, xt_rateest_id);
- int i;
-
- mutex_init(&xn->hash_lock);
- for (i = 0; i < ARRAY_SIZE(xn->hash); i++)
- INIT_HLIST_HEAD(&xn->hash[i]);
- return 0;
-}
-
-static struct pernet_operations xt_rateest_net_ops = {
- .init = xt_rateest_net_init,
- .id = &xt_rateest_id,
- .size = sizeof(struct xt_rateest_net),
-};
-
-static int __init xt_rateest_tg_init(void)
-{
- int err = register_pernet_subsys(&xt_rateest_net_ops);
-
- if (err)
- return err;
- return xt_register_targets(xt_rateest_tg_reg, ARRAY_SIZE(xt_rateest_tg_reg));
-}
-
-static void __exit xt_rateest_tg_fini(void)
-{
- xt_unregister_targets(xt_rateest_tg_reg, ARRAY_SIZE(xt_rateest_tg_reg));
- unregister_pernet_subsys(&xt_rateest_net_ops);
-}
-
-
-MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
-MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("Xtables: packet rate estimator");
-MODULE_ALIAS("ipt_RATEEST");
-MODULE_ALIAS("ip6t_RATEEST");
-module_init(xt_rateest_tg_init);
-module_exit(xt_rateest_tg_fini);
deleted file mode 100644
@@ -1,345 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * This is a module which is used for setting the MSS option in TCP packets.
- *
- * Copyright (C) 2000 Marc Boucher <marc@mbsi.ca>
- * Copyright (C) 2007 Patrick McHardy <kaber@trash.net>
- */
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-#include <linux/module.h>
-#include <linux/skbuff.h>
-#include <linux/ip.h>
-#include <linux/gfp.h>
-#include <linux/ipv6.h>
-#include <linux/tcp.h>
-#include <net/dst.h>
-#include <net/flow.h>
-#include <net/ipv6.h>
-#include <net/route.h>
-#include <net/tcp.h>
-
-#include <linux/netfilter_ipv4/ip_tables.h>
-#include <linux/netfilter_ipv6/ip6_tables.h>
-#include <linux/netfilter/x_tables.h>
-#include <linux/netfilter/xt_tcpudp.h>
-#include <linux/netfilter/xt_tcpmss.h>
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Marc Boucher <marc@mbsi.ca>");
-MODULE_DESCRIPTION("Xtables: TCP Maximum Segment Size (MSS) adjustment");
-MODULE_ALIAS("ipt_TCPMSS");
-MODULE_ALIAS("ip6t_TCPMSS");
-
-static inline unsigned int
-optlen(const u_int8_t *opt, unsigned int offset)
-{
- /* Beware zero-length options: make finite progress */
- if (opt[offset] <= TCPOPT_NOP || opt[offset+1] == 0)
- return 1;
- else
- return opt[offset+1];
-}
-
-static u_int32_t tcpmss_reverse_mtu(struct net *net,
- const struct sk_buff *skb,
- unsigned int family)
-{
- struct flowi fl;
- struct rtable *rt = NULL;
- u_int32_t mtu = ~0U;
-
- if (family == PF_INET) {
- struct flowi4 *fl4 = &fl.u.ip4;
- memset(fl4, 0, sizeof(*fl4));
- fl4->daddr = ip_hdr(skb)->saddr;
- } else {
- struct flowi6 *fl6 = &fl.u.ip6;
-
- memset(fl6, 0, sizeof(*fl6));
- fl6->daddr = ipv6_hdr(skb)->saddr;
- }
-
- nf_route(net, (struct dst_entry **)&rt, &fl, false, family);
- if (rt != NULL) {
- mtu = dst_mtu(&rt->dst);
- dst_release(&rt->dst);
- }
- return mtu;
-}
-
-static int
-tcpmss_mangle_packet(struct sk_buff *skb,
- const struct xt_action_param *par,
- unsigned int family,
- unsigned int tcphoff,
- unsigned int minlen)
-{
- const struct xt_tcpmss_info *info = par->targinfo;
- struct tcphdr *tcph;
- int len, tcp_hdrlen;
- unsigned int i;
- __be16 oldval;
- u16 newmss;
- u8 *opt;
-
- /* This is a fragment, no TCP header is available */
- if (par->fragoff != 0)
- return 0;
-
- if (skb_ensure_writable(skb, skb->len))
- return -1;
-
- len = skb->len - tcphoff;
- if (len < (int)sizeof(struct tcphdr))
- return -1;
-
- tcph = (struct tcphdr *)(skb_network_header(skb) + tcphoff);
- tcp_hdrlen = tcph->doff * 4;
-
- if (len < tcp_hdrlen || tcp_hdrlen < sizeof(struct tcphdr))
- return -1;
-
- if (info->mss == XT_TCPMSS_CLAMP_PMTU) {
- struct net *net = xt_net(par);
- unsigned int in_mtu = tcpmss_reverse_mtu(net, skb, family);
- unsigned int min_mtu = min(dst_mtu(skb_dst(skb)), in_mtu);
-
- if (min_mtu <= minlen) {
- net_err_ratelimited("unknown or invalid path-MTU (%u)\n",
- min_mtu);
- return -1;
- }
- newmss = min_mtu - minlen;
- } else
- newmss = info->mss;
-
- opt = (u_int8_t *)tcph;
- for (i = sizeof(struct tcphdr); i <= tcp_hdrlen - TCPOLEN_MSS; i += optlen(opt, i)) {
- if (opt[i] == TCPOPT_MSS && opt[i+1] == TCPOLEN_MSS) {
- u_int16_t oldmss;
-
- oldmss = (opt[i+2] << 8) | opt[i+3];
-
- /* 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;
-
- inet_proto_csum_replace2(&tcph->check, skb,
- htons(oldmss), htons(newmss),
- false);
- return 0;
- }
- }
-
- /* There is data after the header so the option can't be added
- * without moving it, and doing so may make the SYN packet
- * itself too large. Accept the packet unmodified instead.
- */
- if (len > tcp_hdrlen)
- return 0;
-
- /* tcph->doff has 4 bits, do not wrap it to 0 */
- if (tcp_hdrlen >= 15 * 4)
- return 0;
-
- /*
- * MSS Option not found ?! add it..
- */
- if (skb_tailroom(skb) < TCPOLEN_MSS) {
- if (pskb_expand_head(skb, 0,
- TCPOLEN_MSS - skb_tailroom(skb),
- GFP_ATOMIC))
- return -1;
- tcph = (struct tcphdr *)(skb_network_header(skb) + tcphoff);
- }
-
- skb_put(skb, TCPOLEN_MSS);
-
- /*
- * IPv4: RFC 1122 states "If an MSS option is not received at
- * connection setup, TCP MUST assume a default send MSS of 536".
- * IPv6: RFC 2460 states IPv6 has a minimum MTU of 1280 and a minimum
- * length IPv6 header of 60, ergo the default MSS value is 1220
- * Since no MSS was provided, we must use the default values
- */
- if (xt_family(par) == NFPROTO_IPV4)
- newmss = min(newmss, (u16)536);
- else
- newmss = min(newmss, (u16)1220);
-
- opt = (u_int8_t *)tcph + sizeof(struct tcphdr);
- memmove(opt + TCPOLEN_MSS, opt, len - sizeof(struct tcphdr));
-
- inet_proto_csum_replace2(&tcph->check, skb,
- htons(len), htons(len + TCPOLEN_MSS), true);
- opt[0] = TCPOPT_MSS;
- opt[1] = TCPOLEN_MSS;
- opt[2] = (newmss & 0xff00) >> 8;
- opt[3] = newmss & 0x00ff;
-
- inet_proto_csum_replace4(&tcph->check, skb, 0, *((__be32 *)opt), false);
-
- oldval = ((__be16 *)tcph)[6];
- tcph->doff += TCPOLEN_MSS/4;
- inet_proto_csum_replace2(&tcph->check, skb,
- oldval, ((__be16 *)tcph)[6], false);
- return TCPOLEN_MSS;
-}
-
-static unsigned int
-tcpmss_tg4(struct sk_buff *skb, const struct xt_action_param *par)
-{
- struct iphdr *iph = ip_hdr(skb);
- __be16 newlen;
- int ret;
-
- ret = tcpmss_mangle_packet(skb, par,
- PF_INET,
- iph->ihl * 4,
- sizeof(*iph) + sizeof(struct tcphdr));
- if (ret < 0)
- return NF_DROP;
- if (ret > 0) {
- iph = ip_hdr(skb);
- newlen = htons(ntohs(iph->tot_len) + ret);
- csum_replace2(&iph->check, iph->tot_len, newlen);
- iph->tot_len = newlen;
- }
- return XT_CONTINUE;
-}
-
-#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
-static unsigned int
-tcpmss_tg6(struct sk_buff *skb, const struct xt_action_param *par)
-{
- struct ipv6hdr *ipv6h = ipv6_hdr(skb);
- u8 nexthdr;
- __be16 frag_off, oldlen, newlen;
- int tcphoff;
- int ret;
-
- nexthdr = ipv6h->nexthdr;
- tcphoff = ipv6_skip_exthdr(skb, sizeof(*ipv6h), &nexthdr, &frag_off);
- if (tcphoff < 0)
- return NF_DROP;
- ret = tcpmss_mangle_packet(skb, par,
- PF_INET6,
- tcphoff,
- sizeof(*ipv6h) + sizeof(struct tcphdr));
- if (ret < 0)
- return NF_DROP;
- if (ret > 0) {
- ipv6h = ipv6_hdr(skb);
- oldlen = ipv6h->payload_len;
- newlen = htons(ntohs(oldlen) + ret);
- if (skb->ip_summed == CHECKSUM_COMPLETE)
- skb->csum = csum_add(csum_sub(skb->csum, (__force __wsum)oldlen),
- (__force __wsum)newlen);
- ipv6h->payload_len = newlen;
- }
- return XT_CONTINUE;
-}
-#endif
-
-/* Must specify -p tcp --syn */
-static inline bool find_syn_match(const struct xt_entry_match *m)
-{
- const struct xt_tcp *tcpinfo = (const struct xt_tcp *)m->data;
-
- if (strcmp(m->u.kernel.match->name, "tcp") == 0 &&
- tcpinfo->flg_cmp & TCPHDR_SYN &&
- !(tcpinfo->invflags & XT_TCP_INV_FLAGS))
- return true;
-
- return false;
-}
-
-static int tcpmss_tg4_check(const struct xt_tgchk_param *par)
-{
- const struct xt_tcpmss_info *info = par->targinfo;
- const struct ipt_entry *e = par->entryinfo;
- const struct xt_entry_match *ematch;
-
- if (info->mss == XT_TCPMSS_CLAMP_PMTU &&
- (par->hook_mask & ~((1 << NF_INET_FORWARD) |
- (1 << NF_INET_LOCAL_OUT) |
- (1 << NF_INET_POST_ROUTING))) != 0) {
- pr_info_ratelimited("path-MTU clamping only supported in FORWARD, OUTPUT and POSTROUTING hooks\n");
- return -EINVAL;
- }
- if (par->nft_compat)
- return 0;
-
- xt_ematch_foreach(ematch, e)
- if (find_syn_match(ematch))
- return 0;
- pr_info_ratelimited("Only works on TCP SYN packets\n");
- return -EINVAL;
-}
-
-#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
-static int tcpmss_tg6_check(const struct xt_tgchk_param *par)
-{
- const struct xt_tcpmss_info *info = par->targinfo;
- const struct ip6t_entry *e = par->entryinfo;
- const struct xt_entry_match *ematch;
-
- if (info->mss == XT_TCPMSS_CLAMP_PMTU &&
- (par->hook_mask & ~((1 << NF_INET_FORWARD) |
- (1 << NF_INET_LOCAL_OUT) |
- (1 << NF_INET_POST_ROUTING))) != 0) {
- pr_info_ratelimited("path-MTU clamping only supported in FORWARD, OUTPUT and POSTROUTING hooks\n");
- return -EINVAL;
- }
- if (par->nft_compat)
- return 0;
-
- xt_ematch_foreach(ematch, e)
- if (find_syn_match(ematch))
- return 0;
- pr_info_ratelimited("Only works on TCP SYN packets\n");
- return -EINVAL;
-}
-#endif
-
-static struct xt_target tcpmss_tg_reg[] __read_mostly = {
- {
- .family = NFPROTO_IPV4,
- .name = "TCPMSS",
- .checkentry = tcpmss_tg4_check,
- .target = tcpmss_tg4,
- .targetsize = sizeof(struct xt_tcpmss_info),
- .proto = IPPROTO_TCP,
- .me = THIS_MODULE,
- },
-#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
- {
- .family = NFPROTO_IPV6,
- .name = "TCPMSS",
- .checkentry = tcpmss_tg6_check,
- .target = tcpmss_tg6,
- .targetsize = sizeof(struct xt_tcpmss_info),
- .proto = IPPROTO_TCP,
- .me = THIS_MODULE,
- },
-#endif
-};
-
-static int __init tcpmss_tg_init(void)
-{
- return xt_register_targets(tcpmss_tg_reg, ARRAY_SIZE(tcpmss_tg_reg));
-}
-
-static void __exit tcpmss_tg_exit(void)
-{
- xt_unregister_targets(tcpmss_tg_reg, ARRAY_SIZE(tcpmss_tg_reg));
-}
-
-module_init(tcpmss_tg_init);
-module_exit(tcpmss_tg_exit);
@@ -1,7 +1,11 @@
// SPDX-License-Identifier: GPL-2.0-only
-/* IP tables module for matching the value of the IPv4/IPv6 DSCP field
+/* x_tables module for setting the IPv4/IPv6 DSCP field, Version 1.8
+ * IP tables module for matching and setting the value of the IPv4/IPv6 DSCP field
*
* (C) 2002 by Harald Welte <laforge@netfilter.org>
+ * based on ipt_FTOS.c (C) 2000 by Matthew G. Marsh <mgm@paktronix.com>
+ *
+ * See RFC2474 for a description of the DSCP field within the IP Header.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
@@ -14,12 +18,19 @@
#include <linux/netfilter/xt_dscp.h>
MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
-MODULE_DESCRIPTION("Xtables: DSCP/TOS field match");
+MODULE_DESCRIPTION("Xtables: DSCP/TOS field match and target modification");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_dscp");
MODULE_ALIAS("ip6t_dscp");
MODULE_ALIAS("ipt_tos");
MODULE_ALIAS("ip6t_tos");
+MODULE_ALIAS("ipt_DSCP");
+MODULE_ALIAS("ip6t_DSCP");
+MODULE_ALIAS("ipt_TOS");
+MODULE_ALIAS("ip6t_TOS");
+MODULE_ALIAS("xt_DSCP");
+
+#define XT_DSCP_ECN_MASK 3u
static bool
dscp_mt(const struct sk_buff *skb, struct xt_action_param *par)
@@ -96,15 +107,146 @@ static struct xt_match dscp_mt_reg[] __read_mostly = {
},
};
-static int __init dscp_mt_init(void)
+static unsigned int
+dscp_tg(struct sk_buff *skb, const struct xt_action_param *par)
+{
+ const struct xt_DSCP_info *dinfo = par->targinfo;
+ u8 dscp = ipv4_get_dsfield(ip_hdr(skb)) >> XT_DSCP_SHIFT;
+
+ if (dscp != dinfo->dscp) {
+ if (skb_ensure_writable(skb, sizeof(struct iphdr)))
+ return NF_DROP;
+
+ ipv4_change_dsfield(ip_hdr(skb), XT_DSCP_ECN_MASK,
+ dinfo->dscp << XT_DSCP_SHIFT);
+ }
+ return XT_CONTINUE;
+}
+
+static unsigned int
+dscp_tg6(struct sk_buff *skb, const struct xt_action_param *par)
{
- return xt_register_matches(dscp_mt_reg, ARRAY_SIZE(dscp_mt_reg));
+ const struct xt_DSCP_info *dinfo = par->targinfo;
+ u8 dscp = ipv6_get_dsfield(ipv6_hdr(skb)) >> XT_DSCP_SHIFT;
+
+ if (dscp != dinfo->dscp) {
+ if (skb_ensure_writable(skb, sizeof(struct ipv6hdr)))
+ return NF_DROP;
+
+ ipv6_change_dsfield(ipv6_hdr(skb), XT_DSCP_ECN_MASK,
+ dinfo->dscp << XT_DSCP_SHIFT);
+ }
+ return XT_CONTINUE;
+}
+
+static int dscp_tg_check(const struct xt_tgchk_param *par)
+{
+ const struct xt_DSCP_info *info = par->targinfo;
+
+ if (info->dscp > XT_DSCP_MAX)
+ return -EDOM;
+ return 0;
+}
+
+static unsigned int
+tos_tg(struct sk_buff *skb, const struct xt_action_param *par)
+{
+ const struct xt_tos_target_info *info = par->targinfo;
+ struct iphdr *iph = ip_hdr(skb);
+ u8 orig, nv;
+
+ orig = ipv4_get_dsfield(iph);
+ nv = (orig & ~info->tos_mask) ^ info->tos_value;
+
+ if (orig != nv) {
+ if (skb_ensure_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 xt_action_param *par)
+{
+ const struct xt_tos_target_info *info = par->targinfo;
+ struct ipv6hdr *iph = ipv6_hdr(skb);
+ u8 orig, nv;
+
+ orig = ipv6_get_dsfield(iph);
+ nv = (orig & ~info->tos_mask) ^ info->tos_value;
+
+ if (orig != nv) {
+ if (skb_ensure_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 = NFPROTO_IPV4,
+ .checkentry = dscp_tg_check,
+ .target = dscp_tg,
+ .targetsize = sizeof(struct xt_DSCP_info),
+ .table = "mangle",
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "DSCP",
+ .family = NFPROTO_IPV6,
+ .checkentry = dscp_tg_check,
+ .target = dscp_tg6,
+ .targetsize = sizeof(struct xt_DSCP_info),
+ .table = "mangle",
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "TOS",
+ .revision = 1,
+ .family = NFPROTO_IPV4,
+ .table = "mangle",
+ .target = tos_tg,
+ .targetsize = sizeof(struct xt_tos_target_info),
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "TOS",
+ .revision = 1,
+ .family = NFPROTO_IPV6,
+ .table = "mangle",
+ .target = tos_tg6,
+ .targetsize = sizeof(struct xt_tos_target_info),
+ .me = THIS_MODULE,
+ },
+};
+
+static int __init dscp_init(void)
+{
+ int ret;
+
+ ret = xt_register_targets(dscp_tg_reg, ARRAY_SIZE(dscp_tg_reg));
+ if (ret < 0)
+ return ret;
+ ret = xt_register_matches(dscp_mt_reg, ARRAY_SIZE(dscp_mt_reg));
+ if (ret < 0) {
+ xt_unregister_targets(dscp_tg_reg, ARRAY_SIZE(dscp_tg_reg));
+ return ret;
+ }
+ return 0;
}
-static void __exit dscp_mt_exit(void)
+static void __exit dscp_exit(void)
{
xt_unregister_matches(dscp_mt_reg, ARRAY_SIZE(dscp_mt_reg));
+ xt_unregister_targets(dscp_tg_reg, ARRAY_SIZE(dscp_tg_reg));
}
-module_init(dscp_mt_init);
-module_exit(dscp_mt_exit);
+module_init(dscp_init);
+module_exit(dscp_exit);
@@ -5,22 +5,33 @@
*
* Hop Limit matching module
* (C) 2001-2002 Maciej Soltysiak <solt@dns.toxicfilms.tv>
+ *
+ * TTL modification target for IP tables
+ * (C) 2000,2005 by Harald Welte <laforge@netfilter.org>
+ *
+ * Hop Limit modification target for ip6tables
+ * Maciej Soltysiak <solt@dns.toxicfilms.tv>
*/
-
-#include <linux/ip.h>
-#include <linux/ipv6.h>
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/skbuff.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <net/checksum.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_ipv4/ipt_ttl.h>
#include <linux/netfilter_ipv6/ip6t_hl.h>
+MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
MODULE_AUTHOR("Maciej Soltysiak <solt@dns.toxicfilms.tv>");
-MODULE_DESCRIPTION("Xtables: Hoplimit/TTL field match");
+MODULE_DESCRIPTION("Xtables: Hoplimit/TTL field match and target modification");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_ttl");
MODULE_ALIAS("ip6t_hl");
+MODULE_ALIAS("ipt_TTL");
+MODULE_ALIAS("ip6t_HL");
+MODULE_ALIAS("xt_HL");
static bool ttl_mt(const struct sk_buff *skb, struct xt_action_param *par)
{
@@ -79,15 +90,146 @@ static struct xt_match hl_mt_reg[] __read_mostly = {
},
};
-static int __init hl_mt_init(void)
+static unsigned int
+ttl_tg(struct sk_buff *skb, const struct xt_action_param *par)
+{
+ struct iphdr *iph;
+ const struct ipt_TTL_info *info = par->targinfo;
+ int new_ttl;
+
+ if (skb_ensure_writable(skb, sizeof(*iph)))
+ return NF_DROP;
+
+ iph = ip_hdr(skb);
+
+ switch (info->mode) {
+ case IPT_TTL_SET:
+ new_ttl = info->ttl;
+ break;
+ case IPT_TTL_INC:
+ new_ttl = iph->ttl + info->ttl;
+ if (new_ttl > 255)
+ new_ttl = 255;
+ break;
+ case IPT_TTL_DEC:
+ new_ttl = iph->ttl - info->ttl;
+ if (new_ttl < 0)
+ new_ttl = 0;
+ break;
+ default:
+ new_ttl = iph->ttl;
+ break;
+ }
+
+ if (new_ttl != iph->ttl) {
+ csum_replace2(&iph->check, htons(iph->ttl << 8), htons(new_ttl << 8));
+ iph->ttl = new_ttl;
+ }
+
+ return XT_CONTINUE;
+}
+
+static unsigned int
+hl_tg6(struct sk_buff *skb, const struct xt_action_param *par)
+{
+ struct ipv6hdr *ip6h;
+ const struct ip6t_HL_info *info = par->targinfo;
+ int new_hl;
+
+ if (skb_ensure_writable(skb, sizeof(*ip6h)))
+ return NF_DROP;
+
+ ip6h = ipv6_hdr(skb);
+
+ switch (info->mode) {
+ case IP6T_HL_SET:
+ new_hl = info->hop_limit;
+ break;
+ case IP6T_HL_INC:
+ new_hl = ip6h->hop_limit + info->hop_limit;
+ if (new_hl > 255)
+ new_hl = 255;
+ break;
+ case IP6T_HL_DEC:
+ new_hl = ip6h->hop_limit - info->hop_limit;
+ if (new_hl < 0)
+ new_hl = 0;
+ break;
+ default:
+ new_hl = ip6h->hop_limit;
+ break;
+ }
+
+ ip6h->hop_limit = new_hl;
+
+ return XT_CONTINUE;
+}
+
+static int ttl_tg_check(const struct xt_tgchk_param *par)
+{
+ const struct ipt_TTL_info *info = par->targinfo;
+
+ if (info->mode > IPT_TTL_MAXMODE)
+ return -EINVAL;
+ if (info->mode != IPT_TTL_SET && info->ttl == 0)
+ return -EINVAL;
+ return 0;
+}
+
+static int hl_tg6_check(const struct xt_tgchk_param *par)
+{
+ const struct ip6t_HL_info *info = par->targinfo;
+
+ if (info->mode > IP6T_HL_MAXMODE)
+ return -EINVAL;
+ if (info->mode != IP6T_HL_SET && info->hop_limit == 0)
+ return -EINVAL;
+ return 0;
+}
+
+static struct xt_target hl_tg_reg[] __read_mostly = {
+ {
+ .name = "TTL",
+ .revision = 0,
+ .family = NFPROTO_IPV4,
+ .target = ttl_tg,
+ .targetsize = sizeof(struct ipt_TTL_info),
+ .table = "mangle",
+ .checkentry = ttl_tg_check,
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "HL",
+ .revision = 0,
+ .family = NFPROTO_IPV6,
+ .target = hl_tg6,
+ .targetsize = sizeof(struct ip6t_HL_info),
+ .table = "mangle",
+ .checkentry = hl_tg6_check,
+ .me = THIS_MODULE,
+ },
+};
+
+static int __init hl_init(void)
{
- return xt_register_matches(hl_mt_reg, ARRAY_SIZE(hl_mt_reg));
+ int ret;
+
+ ret = xt_register_targets(hl_tg_reg, ARRAY_SIZE(hl_tg_reg));
+ if (ret < 0)
+ return ret;
+ ret = xt_register_matches(hl_mt_reg, ARRAY_SIZE(hl_mt_reg));
+ if (ret < 0) {
+ xt_unregister_targets(hl_tg_reg, ARRAY_SIZE(hl_tg_reg));
+ return ret;
+ }
+ return 0;
}
-static void __exit hl_mt_exit(void)
+static void __exit hl_exit(void)
{
xt_unregister_matches(hl_mt_reg, ARRAY_SIZE(hl_mt_reg));
+ xt_unregister_targets(hl_tg_reg, ARRAY_SIZE(hl_tg_reg));
}
-module_init(hl_mt_init);
-module_exit(hl_mt_exit);
+module_init(hl_init);
+module_exit(hl_exit);
@@ -5,11 +5,28 @@
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/gen_stats.h>
+#include <linux/jhash.h>
+#include <linux/rtnetlink.h>
+#include <linux/random.h>
+#include <linux/slab.h>
+#include <net/gen_stats.h>
+#include <net/netlink.h>
+#include <net/netns/generic.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_rateest.h>
#include <net/netfilter/xt_rateest.h>
+#define RATEEST_HSIZE 16
+
+MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("xtables packet rate estimator");
+MODULE_ALIAS("ipt_rateest");
+MODULE_ALIAS("ip6t_rateest");
+MODULE_ALIAS("ipt_RATEEST");
+MODULE_ALIAS("ip6t_RATEEST");
+MODULE_ALIAS("xt_RATEEST");
static bool
xt_rateest_mt(const struct sk_buff *skb, struct xt_action_param *par)
@@ -134,20 +151,236 @@ static struct xt_match xt_rateest_mt_reg __read_mostly = {
.me = THIS_MODULE,
};
-static int __init xt_rateest_mt_init(void)
+struct xt_rateest_net {
+ /* To synchronize concurrent synchronous rate estimator operations. */
+ struct mutex hash_lock;
+ struct hlist_head hash[RATEEST_HSIZE];
+};
+
+static unsigned int xt_rateest_id;
+
+static unsigned int jhash_rnd __read_mostly;
+
+static unsigned int xt_rateest_hash(const char *name)
+{
+ return jhash(name, sizeof_field(struct xt_rateest, name), jhash_rnd) &
+ (RATEEST_HSIZE - 1);
+}
+
+static void xt_rateest_hash_insert(struct xt_rateest_net *xn,
+ struct xt_rateest *est)
+{
+ unsigned int h;
+
+ h = xt_rateest_hash(est->name);
+ hlist_add_head(&est->list, &xn->hash[h]);
+}
+
+static struct xt_rateest *__xt_rateest_lookup(struct xt_rateest_net *xn,
+ const char *name)
{
- return xt_register_match(&xt_rateest_mt_reg);
+ struct xt_rateest *est;
+ unsigned int h;
+
+ h = xt_rateest_hash(name);
+ hlist_for_each_entry(est, &xn->hash[h], list) {
+ if (strcmp(est->name, name) == 0) {
+ est->refcnt++;
+ return est;
+ }
+ }
+
+ return NULL;
}
-static void __exit xt_rateest_mt_fini(void)
+struct xt_rateest *xt_rateest_lookup(struct net *net, const char *name)
+{
+ struct xt_rateest_net *xn = net_generic(net, xt_rateest_id);
+ struct xt_rateest *est;
+
+ mutex_lock(&xn->hash_lock);
+ est = __xt_rateest_lookup(xn, name);
+ mutex_unlock(&xn->hash_lock);
+ return est;
+}
+EXPORT_SYMBOL_GPL(xt_rateest_lookup);
+
+void xt_rateest_put(struct net *net, struct xt_rateest *est)
+{
+ struct xt_rateest_net *xn = net_generic(net, xt_rateest_id);
+
+ mutex_lock(&xn->hash_lock);
+ if (--est->refcnt == 0) {
+ hlist_del(&est->list);
+ gen_kill_estimator(&est->rate_est);
+ /*
+ * gen_estimator est_timer() might access est->lock or bstats,
+ * wait a RCU grace period before freeing 'est'
+ */
+ kfree_rcu(est, rcu);
+ }
+ mutex_unlock(&xn->hash_lock);
+}
+EXPORT_SYMBOL_GPL(xt_rateest_put);
+
+static unsigned int
+xt_rateest_tg(struct sk_buff *skb, const struct xt_action_param *par)
+{
+ const struct xt_rateest_target_info *info = par->targinfo;
+ struct gnet_stats_basic_sync *stats = &info->est->bstats;
+
+ spin_lock_bh(&info->est->lock);
+ u64_stats_add(&stats->bytes, skb->len);
+ u64_stats_inc(&stats->packets);
+ spin_unlock_bh(&info->est->lock);
+
+ return XT_CONTINUE;
+}
+
+static int xt_rateest_tg_checkentry(const struct xt_tgchk_param *par)
+{
+ struct xt_rateest_net *xn = net_generic(par->net, xt_rateest_id);
+ struct xt_rateest_target_info *info = par->targinfo;
+ struct xt_rateest *est;
+ struct {
+ struct nlattr opt;
+ struct gnet_estimator est;
+ } cfg;
+ int ret;
+
+ if (strnlen(info->name, sizeof(est->name)) >= sizeof(est->name))
+ return -ENAMETOOLONG;
+
+ net_get_random_once(&jhash_rnd, sizeof(jhash_rnd));
+
+ mutex_lock(&xn->hash_lock);
+ est = __xt_rateest_lookup(xn, info->name);
+ if (est) {
+ mutex_unlock(&xn->hash_lock);
+ /*
+ * If estimator parameters are specified, they must match the
+ * existing estimator.
+ */
+ if ((!info->interval && !info->ewma_log) ||
+ (info->interval != est->params.interval ||
+ info->ewma_log != est->params.ewma_log)) {
+ xt_rateest_put(par->net, est);
+ return -EINVAL;
+ }
+ info->est = est;
+ return 0;
+ }
+
+ ret = -ENOMEM;
+ est = kzalloc(sizeof(*est), GFP_KERNEL);
+ if (!est)
+ goto err1;
+
+ gnet_stats_basic_sync_init(&est->bstats);
+ strscpy(est->name, info->name, sizeof(est->name));
+ spin_lock_init(&est->lock);
+ est->refcnt = 1;
+ est->params.interval = info->interval;
+ est->params.ewma_log = info->ewma_log;
+
+ cfg.opt.nla_len = nla_attr_size(sizeof(cfg.est));
+ cfg.opt.nla_type = TCA_STATS_RATE_EST;
+ cfg.est.interval = info->interval;
+ cfg.est.ewma_log = info->ewma_log;
+
+ ret = gen_new_estimator(&est->bstats, NULL, &est->rate_est,
+ &est->lock, NULL, &cfg.opt);
+ if (ret < 0)
+ goto err2;
+
+ info->est = est;
+ xt_rateest_hash_insert(xn, est);
+ mutex_unlock(&xn->hash_lock);
+ return 0;
+
+err2:
+ kfree(est);
+err1:
+ mutex_unlock(&xn->hash_lock);
+ return ret;
+}
+
+static void xt_rateest_tg_destroy(const struct xt_tgdtor_param *par)
+{
+ struct xt_rateest_target_info *info = par->targinfo;
+
+ xt_rateest_put(par->net, info->est);
+}
+
+static struct xt_target xt_rateest_tg_reg[] __read_mostly = {
+ {
+ .name = "RATEEST",
+ .revision = 0,
+ .family = NFPROTO_IPV4,
+ .target = xt_rateest_tg,
+ .checkentry = xt_rateest_tg_checkentry,
+ .destroy = xt_rateest_tg_destroy,
+ .targetsize = sizeof(struct xt_rateest_target_info),
+ .usersize = offsetof(struct xt_rateest_target_info, est),
+ .me = THIS_MODULE,
+ },
+#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
+ {
+ .name = "RATEEST",
+ .revision = 0,
+ .family = NFPROTO_IPV6,
+ .target = xt_rateest_tg,
+ .checkentry = xt_rateest_tg_checkentry,
+ .destroy = xt_rateest_tg_destroy,
+ .targetsize = sizeof(struct xt_rateest_target_info),
+ .usersize = offsetof(struct xt_rateest_target_info, est),
+ .me = THIS_MODULE,
+ },
+#endif
+};
+
+static __net_init int xt_rateest_net_init(struct net *net)
+{
+ struct xt_rateest_net *xn = net_generic(net, xt_rateest_id);
+ int i;
+
+ mutex_init(&xn->hash_lock);
+ for (i = 0; i < ARRAY_SIZE(xn->hash); i++)
+ INIT_HLIST_HEAD(&xn->hash[i]);
+ return 0;
+}
+
+static struct pernet_operations xt_rateest_net_ops = {
+ .init = xt_rateest_net_init,
+ .id = &xt_rateest_id,
+ .size = sizeof(struct xt_rateest_net),
+};
+
+static int __init xt_rateest_init(void)
+{
+ int ret = register_pernet_subsys(&xt_rateest_net_ops);
+
+ if (ret)
+ return ret;
+
+ ret = xt_register_targets(xt_rateest_tg_reg, ARRAY_SIZE(xt_rateest_tg_reg));
+ if (ret < 0)
+ return ret;
+ ret = xt_register_match(&xt_rateest_mt_reg);
+ if (ret < 0) {
+ xt_unregister_targets(xt_rateest_tg_reg, ARRAY_SIZE(xt_rateest_tg_reg));
+ unregister_pernet_subsys(&xt_rateest_net_ops);
+ return ret;
+ }
+ return 0;
+}
+
+static void __exit xt_rateest_exit(void)
{
xt_unregister_match(&xt_rateest_mt_reg);
+ xt_unregister_targets(xt_rateest_tg_reg, ARRAY_SIZE(xt_rateest_tg_reg));
+ unregister_pernet_subsys(&xt_rateest_net_ops);
}
-MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
-MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("xtables rate estimator match");
-MODULE_ALIAS("ipt_rateest");
-MODULE_ALIAS("ip6t_rateest");
-module_init(xt_rateest_mt_init);
-module_exit(xt_rateest_mt_fini);
+module_init(xt_rateest_init);
+module_exit(xt_rateest_exit);
@@ -1,25 +1,38 @@
// SPDX-License-Identifier: GPL-2.0-only
-/* Kernel module to match TCP MSS values. */
-
-/* Copyright (C) 2000 Marc Boucher <marc@mbsi.ca>
+/* Kernel module to match TCP MSS values.
+ * This is a module which is used for setting the MSS option in TCP packets.
+ *
+ * Copyright (C) 2000 Marc Boucher <marc@mbsi.ca>
* Portions (C) 2005 by Harald Welte <laforge@netfilter.org>
+ * Copyright (C) 2007 Patrick McHardy <kaber@trash.net>
*/
-
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/skbuff.h>
+#include <linux/ip.h>
+#include <linux/gfp.h>
+#include <linux/ipv6.h>
+#include <linux/tcp.h>
+#include <net/dst.h>
+#include <net/flow.h>
+#include <net/ipv6.h>
+#include <net/route.h>
#include <net/tcp.h>
-#include <linux/netfilter/xt_tcpmss.h>
-#include <linux/netfilter/x_tables.h>
-
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
+#include <linux/netfilter/x_tables.h>
+#include <linux/netfilter/xt_tcpudp.h>
+#include <linux/netfilter/xt_tcpmss.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Marc Boucher <marc@mbsi.ca>");
-MODULE_DESCRIPTION("Xtables: TCP MSS match");
+MODULE_DESCRIPTION("Xtables: TCP Maximum Segment Size (MSS) adjustment and match");
MODULE_ALIAS("ipt_tcpmss");
MODULE_ALIAS("ip6t_tcpmss");
+MODULE_ALIAS("ipt_TCPMSS");
+MODULE_ALIAS("ip6t_TCPMSS");
+MODULE_ALIAS("xt_TCPMSS");
static bool
tcpmss_mt(const struct sk_buff *skb, struct xt_action_param *par)
@@ -93,15 +106,329 @@ static struct xt_match tcpmss_mt_reg[] __read_mostly = {
},
};
-static int __init tcpmss_mt_init(void)
+static inline unsigned int
+optlen(const u8 *opt, unsigned int offset)
+{
+ /* Beware zero-length options: make finite progress */
+ if (opt[offset] <= TCPOPT_NOP || opt[offset + 1] == 0)
+ return 1;
+ else
+ return opt[offset + 1];
+}
+
+static u_int32_t tcpmss_reverse_mtu(struct net *net,
+ const struct sk_buff *skb,
+ unsigned int family)
+{
+ struct flowi fl;
+ struct rtable *rt = NULL;
+ u32 mtu = ~0U;
+
+ if (family == PF_INET) {
+ struct flowi4 *fl4 = &fl.u.ip4;
+
+ memset(fl4, 0, sizeof(*fl4));
+ fl4->daddr = ip_hdr(skb)->saddr;
+ } else {
+ struct flowi6 *fl6 = &fl.u.ip6;
+
+ memset(fl6, 0, sizeof(*fl6));
+ fl6->daddr = ipv6_hdr(skb)->saddr;
+ }
+
+ nf_route(net, (struct dst_entry **)&rt, &fl, false, family);
+ if (rt) {
+ mtu = dst_mtu(&rt->dst);
+ dst_release(&rt->dst);
+ }
+ return mtu;
+}
+
+static int
+tcpmss_mangle_packet(struct sk_buff *skb,
+ const struct xt_action_param *par,
+ unsigned int family,
+ unsigned int tcphoff,
+ unsigned int minlen)
+{
+ const struct xt_tcpmss_info *info = par->targinfo;
+ struct tcphdr *tcph;
+ int len, tcp_hdrlen;
+ unsigned int i;
+ __be16 oldval;
+ u16 newmss;
+ u8 *opt;
+
+ /* This is a fragment, no TCP header is available */
+ if (par->fragoff != 0)
+ return 0;
+
+ if (skb_ensure_writable(skb, skb->len))
+ return -1;
+
+ len = skb->len - tcphoff;
+ if (len < (int)sizeof(struct tcphdr))
+ return -1;
+
+ tcph = (struct tcphdr *)(skb_network_header(skb) + tcphoff);
+ tcp_hdrlen = tcph->doff * 4;
+
+ if (len < tcp_hdrlen || tcp_hdrlen < sizeof(struct tcphdr))
+ return -1;
+
+ if (info->mss == XT_TCPMSS_CLAMP_PMTU) {
+ struct net *net = xt_net(par);
+ unsigned int in_mtu = tcpmss_reverse_mtu(net, skb, family);
+ unsigned int min_mtu = min(dst_mtu(skb_dst(skb)), in_mtu);
+
+ if (min_mtu <= minlen) {
+ net_err_ratelimited("unknown or invalid path-MTU (%u)\n",
+ min_mtu);
+ return -1;
+ }
+ newmss = min_mtu - minlen;
+ } else {
+ newmss = info->mss;
+ }
+
+ opt = (u_int8_t *)tcph;
+ for (i = sizeof(struct tcphdr); i <= tcp_hdrlen - TCPOLEN_MSS; i += optlen(opt, i)) {
+ if (opt[i] == TCPOPT_MSS && opt[i + 1] == TCPOLEN_MSS) {
+ u16 oldmss;
+
+ oldmss = (opt[i + 2] << 8) | opt[i + 3];
+
+ /* 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;
+
+ inet_proto_csum_replace2(&tcph->check, skb,
+ htons(oldmss), htons(newmss),
+ false);
+ return 0;
+ }
+ }
+
+ /* There is data after the header so the option can't be added
+ * without moving it, and doing so may make the SYN packet
+ * itself too large. Accept the packet unmodified instead.
+ */
+ if (len > tcp_hdrlen)
+ return 0;
+
+ /* tcph->doff has 4 bits, do not wrap it to 0 */
+ if (tcp_hdrlen >= 15 * 4)
+ return 0;
+
+ /*
+ * MSS Option not found ?! add it..
+ */
+ if (skb_tailroom(skb) < TCPOLEN_MSS) {
+ if (pskb_expand_head(skb, 0,
+ TCPOLEN_MSS - skb_tailroom(skb),
+ GFP_ATOMIC))
+ return -1;
+ tcph = (struct tcphdr *)(skb_network_header(skb) + tcphoff);
+ }
+
+ skb_put(skb, TCPOLEN_MSS);
+
+ /*
+ * IPv4: RFC 1122 states "If an MSS option is not received at
+ * connection setup, TCP MUST assume a default send MSS of 536".
+ * IPv6: RFC 2460 states IPv6 has a minimum MTU of 1280 and a minimum
+ * length IPv6 header of 60, ergo the default MSS value is 1220
+ * Since no MSS was provided, we must use the default values
+ */
+ if (xt_family(par) == NFPROTO_IPV4)
+ newmss = min(newmss, (u16)536);
+ else
+ newmss = min(newmss, (u16)1220);
+
+ opt = (u_int8_t *)tcph + sizeof(struct tcphdr);
+ memmove(opt + TCPOLEN_MSS, opt, len - sizeof(struct tcphdr));
+
+ inet_proto_csum_replace2(&tcph->check, skb,
+ htons(len), htons(len + TCPOLEN_MSS), true);
+ opt[0] = TCPOPT_MSS;
+ opt[1] = TCPOLEN_MSS;
+ opt[2] = (newmss & 0xff00) >> 8;
+ opt[3] = newmss & 0x00ff;
+
+ inet_proto_csum_replace4(&tcph->check, skb, 0, *((__be32 *)opt), false);
+
+ oldval = ((__be16 *)tcph)[6];
+ tcph->doff += TCPOLEN_MSS / 4;
+ inet_proto_csum_replace2(&tcph->check, skb,
+ oldval, ((__be16 *)tcph)[6], false);
+ return TCPOLEN_MSS;
+}
+
+static unsigned int
+tcpmss_tg4(struct sk_buff *skb, const struct xt_action_param *par)
+{
+ struct iphdr *iph = ip_hdr(skb);
+ __be16 newlen;
+ int ret;
+
+ ret = tcpmss_mangle_packet(skb, par,
+ PF_INET,
+ iph->ihl * 4,
+ sizeof(*iph) + sizeof(struct tcphdr));
+ if (ret < 0)
+ return NF_DROP;
+ if (ret > 0) {
+ iph = ip_hdr(skb);
+ newlen = htons(ntohs(iph->tot_len) + ret);
+ csum_replace2(&iph->check, iph->tot_len, newlen);
+ iph->tot_len = newlen;
+ }
+ return XT_CONTINUE;
+}
+
+#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
+static unsigned int
+tcpmss_tg6(struct sk_buff *skb, const struct xt_action_param *par)
+{
+ struct ipv6hdr *ipv6h = ipv6_hdr(skb);
+ u8 nexthdr;
+ __be16 frag_off, oldlen, newlen;
+ int tcphoff;
+ int ret;
+
+ nexthdr = ipv6h->nexthdr;
+ tcphoff = ipv6_skip_exthdr(skb, sizeof(*ipv6h), &nexthdr, &frag_off);
+ if (tcphoff < 0)
+ return NF_DROP;
+ ret = tcpmss_mangle_packet(skb, par,
+ PF_INET6,
+ tcphoff,
+ sizeof(*ipv6h) + sizeof(struct tcphdr));
+ if (ret < 0)
+ return NF_DROP;
+ if (ret > 0) {
+ ipv6h = ipv6_hdr(skb);
+ oldlen = ipv6h->payload_len;
+ newlen = htons(ntohs(oldlen) + ret);
+ if (skb->ip_summed == CHECKSUM_COMPLETE)
+ skb->csum = csum_add(csum_sub(skb->csum, (__force __wsum)oldlen),
+ (__force __wsum)newlen);
+ ipv6h->payload_len = newlen;
+ }
+ return XT_CONTINUE;
+}
+#endif
+
+/* Must specify -p tcp --syn */
+static inline bool find_syn_match(const struct xt_entry_match *m)
+{
+ const struct xt_tcp *tcpinfo = (const struct xt_tcp *)m->data;
+
+ if (strcmp(m->u.kernel.match->name, "tcp") == 0 &&
+ tcpinfo->flg_cmp & TCPHDR_SYN &&
+ !(tcpinfo->invflags & XT_TCP_INV_FLAGS))
+ return true;
+
+ return false;
+}
+
+static int tcpmss_tg4_check(const struct xt_tgchk_param *par)
+{
+ const struct xt_tcpmss_info *info = par->targinfo;
+ const struct ipt_entry *e = par->entryinfo;
+ const struct xt_entry_match *ematch;
+
+ if (info->mss == XT_TCPMSS_CLAMP_PMTU &&
+ (par->hook_mask & ~((1 << NF_INET_FORWARD) |
+ (1 << NF_INET_LOCAL_OUT) |
+ (1 << NF_INET_POST_ROUTING))) != 0) {
+ pr_info_ratelimited("path-MTU clamping only supported in FORWARD, OUTPUT and POSTROUTING hooks\n");
+ return -EINVAL;
+ }
+ if (par->nft_compat)
+ return 0;
+
+ xt_ematch_foreach(ematch, e)
+ if (find_syn_match(ematch))
+ return 0;
+ pr_info_ratelimited("Only works on TCP SYN packets\n");
+ return -EINVAL;
+}
+
+#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
+static int tcpmss_tg6_check(const struct xt_tgchk_param *par)
+{
+ const struct xt_tcpmss_info *info = par->targinfo;
+ const struct ip6t_entry *e = par->entryinfo;
+ const struct xt_entry_match *ematch;
+
+ if (info->mss == XT_TCPMSS_CLAMP_PMTU &&
+ (par->hook_mask & ~((1 << NF_INET_FORWARD) |
+ (1 << NF_INET_LOCAL_OUT) |
+ (1 << NF_INET_POST_ROUTING))) != 0) {
+ pr_info_ratelimited("path-MTU clamping only supported in FORWARD, OUTPUT and POSTROUTING hooks\n");
+ return -EINVAL;
+ }
+ if (par->nft_compat)
+ return 0;
+
+ xt_ematch_foreach(ematch, e)
+ if (find_syn_match(ematch))
+ return 0;
+ pr_info_ratelimited("Only works on TCP SYN packets\n");
+ return -EINVAL;
+}
+#endif
+
+static struct xt_target tcpmss_tg_reg[] __read_mostly = {
+ {
+ .family = NFPROTO_IPV4,
+ .name = "TCPMSS",
+ .checkentry = tcpmss_tg4_check,
+ .target = tcpmss_tg4,
+ .targetsize = sizeof(struct xt_tcpmss_info),
+ .proto = IPPROTO_TCP,
+ .me = THIS_MODULE,
+ },
+#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
+ {
+ .family = NFPROTO_IPV6,
+ .name = "TCPMSS",
+ .checkentry = tcpmss_tg6_check,
+ .target = tcpmss_tg6,
+ .targetsize = sizeof(struct xt_tcpmss_info),
+ .proto = IPPROTO_TCP,
+ .me = THIS_MODULE,
+ },
+#endif
+};
+
+static int __init tcpmss_init(void)
{
- return xt_register_matches(tcpmss_mt_reg, ARRAY_SIZE(tcpmss_mt_reg));
+ int ret;
+
+ ret = xt_register_targets(tcpmss_tg_reg, ARRAY_SIZE(tcpmss_tg_reg));
+ if (ret < 0)
+ return ret;
+ ret = xt_register_matches(tcpmss_mt_reg, ARRAY_SIZE(tcpmss_mt_reg));
+ if (ret < 0) {
+ xt_unregister_targets(tcpmss_tg_reg, ARRAY_SIZE(tcpmss_tg_reg));
+ return ret;
+ }
+ return 0;
}
-static void __exit tcpmss_mt_exit(void)
+static void __exit tcpmss_exit(void)
{
xt_unregister_matches(tcpmss_mt_reg, ARRAY_SIZE(tcpmss_mt_reg));
+ xt_unregister_targets(tcpmss_tg_reg, ARRAY_SIZE(tcpmss_tg_reg));
}
-module_init(tcpmss_mt_init);
-module_exit(tcpmss_mt_exit);
+module_init(tcpmss_init);
+module_exit(tcpmss_exit);