alistair23-linux/include/uapi/linux/ip.h
Johannes Berg 12b74dfadb ipv4: add option to drop unicast encapsulated in L2 multicast
In order to solve a problem with 802.11, the so-called hole-196 attack,
add an option (sysctl) called "drop_unicast_in_l2_multicast" which, if
enabled, causes the stack to drop IPv4 unicast packets encapsulated in
link-layer multi- or broadcast frames. Such frames can (as an attack)
be created by any member of the same wireless network and transmitted
as valid encrypted frames since the symmetric key for broadcast frames
is shared between all stations.

Additionally, enabling this option provides compliance with a SHOULD
clause of RFC 1122.

Reviewed-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11 04:27:35 -05:00

175 lines
4.5 KiB
C

/*
* INET An implementation of the TCP/IP protocol suite for the LINUX
* operating system. INET is implemented using the BSD Socket
* interface as the means of communication with the user level.
*
* Definitions for the IP protocol.
*
* Version: @(#)ip.h 1.0.2 04/28/93
*
* Authors: Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifndef _UAPI_LINUX_IP_H
#define _UAPI_LINUX_IP_H
#include <linux/types.h>
#include <asm/byteorder.h>
#define IPTOS_TOS_MASK 0x1E
#define IPTOS_TOS(tos) ((tos)&IPTOS_TOS_MASK)
#define IPTOS_LOWDELAY 0x10
#define IPTOS_THROUGHPUT 0x08
#define IPTOS_RELIABILITY 0x04
#define IPTOS_MINCOST 0x02
#define IPTOS_PREC_MASK 0xE0
#define IPTOS_PREC(tos) ((tos)&IPTOS_PREC_MASK)
#define IPTOS_PREC_NETCONTROL 0xe0
#define IPTOS_PREC_INTERNETCONTROL 0xc0
#define IPTOS_PREC_CRITIC_ECP 0xa0
#define IPTOS_PREC_FLASHOVERRIDE 0x80
#define IPTOS_PREC_FLASH 0x60
#define IPTOS_PREC_IMMEDIATE 0x40
#define IPTOS_PREC_PRIORITY 0x20
#define IPTOS_PREC_ROUTINE 0x00
/* IP options */
#define IPOPT_COPY 0x80
#define IPOPT_CLASS_MASK 0x60
#define IPOPT_NUMBER_MASK 0x1f
#define IPOPT_COPIED(o) ((o)&IPOPT_COPY)
#define IPOPT_CLASS(o) ((o)&IPOPT_CLASS_MASK)
#define IPOPT_NUMBER(o) ((o)&IPOPT_NUMBER_MASK)
#define IPOPT_CONTROL 0x00
#define IPOPT_RESERVED1 0x20
#define IPOPT_MEASUREMENT 0x40
#define IPOPT_RESERVED2 0x60
#define IPOPT_END (0 |IPOPT_CONTROL)
#define IPOPT_NOOP (1 |IPOPT_CONTROL)
#define IPOPT_SEC (2 |IPOPT_CONTROL|IPOPT_COPY)
#define IPOPT_LSRR (3 |IPOPT_CONTROL|IPOPT_COPY)
#define IPOPT_TIMESTAMP (4 |IPOPT_MEASUREMENT)
#define IPOPT_CIPSO (6 |IPOPT_CONTROL|IPOPT_COPY)
#define IPOPT_RR (7 |IPOPT_CONTROL)
#define IPOPT_SID (8 |IPOPT_CONTROL|IPOPT_COPY)
#define IPOPT_SSRR (9 |IPOPT_CONTROL|IPOPT_COPY)
#define IPOPT_RA (20|IPOPT_CONTROL|IPOPT_COPY)
#define IPVERSION 4
#define MAXTTL 255
#define IPDEFTTL 64
#define IPOPT_OPTVAL 0
#define IPOPT_OLEN 1
#define IPOPT_OFFSET 2
#define IPOPT_MINOFF 4
#define MAX_IPOPTLEN 40
#define IPOPT_NOP IPOPT_NOOP
#define IPOPT_EOL IPOPT_END
#define IPOPT_TS IPOPT_TIMESTAMP
#define IPOPT_TS_TSONLY 0 /* timestamps only */
#define IPOPT_TS_TSANDADDR 1 /* timestamps and addresses */
#define IPOPT_TS_PRESPEC 3 /* specified modules only */
#define IPV4_BEET_PHMAXLEN 8
struct iphdr {
#if defined(__LITTLE_ENDIAN_BITFIELD)
__u8 ihl:4,
version:4;
#elif defined (__BIG_ENDIAN_BITFIELD)
__u8 version:4,
ihl:4;
#else
#error "Please fix <asm/byteorder.h>"
#endif
__u8 tos;
__be16 tot_len;
__be16 id;
__be16 frag_off;
__u8 ttl;
__u8 protocol;
__sum16 check;
__be32 saddr;
__be32 daddr;
/*The options start here. */
};
struct ip_auth_hdr {
__u8 nexthdr;
__u8 hdrlen; /* This one is measured in 32 bit units! */
__be16 reserved;
__be32 spi;
__be32 seq_no; /* Sequence number */
__u8 auth_data[0]; /* Variable len but >=4. Mind the 64 bit alignment! */
};
struct ip_esp_hdr {
__be32 spi;
__be32 seq_no; /* Sequence number */
__u8 enc_data[0]; /* Variable len but >=8. Mind the 64 bit alignment! */
};
struct ip_comp_hdr {
__u8 nexthdr;
__u8 flags;
__be16 cpi;
};
struct ip_beet_phdr {
__u8 nexthdr;
__u8 hdrlen;
__u8 padlen;
__u8 reserved;
};
/* index values for the variables in ipv4_devconf */
enum
{
IPV4_DEVCONF_FORWARDING=1,
IPV4_DEVCONF_MC_FORWARDING,
IPV4_DEVCONF_PROXY_ARP,
IPV4_DEVCONF_ACCEPT_REDIRECTS,
IPV4_DEVCONF_SECURE_REDIRECTS,
IPV4_DEVCONF_SEND_REDIRECTS,
IPV4_DEVCONF_SHARED_MEDIA,
IPV4_DEVCONF_RP_FILTER,
IPV4_DEVCONF_ACCEPT_SOURCE_ROUTE,
IPV4_DEVCONF_BOOTP_RELAY,
IPV4_DEVCONF_LOG_MARTIANS,
IPV4_DEVCONF_TAG,
IPV4_DEVCONF_ARPFILTER,
IPV4_DEVCONF_MEDIUM_ID,
IPV4_DEVCONF_NOXFRM,
IPV4_DEVCONF_NOPOLICY,
IPV4_DEVCONF_FORCE_IGMP_VERSION,
IPV4_DEVCONF_ARP_ANNOUNCE,
IPV4_DEVCONF_ARP_IGNORE,
IPV4_DEVCONF_PROMOTE_SECONDARIES,
IPV4_DEVCONF_ARP_ACCEPT,
IPV4_DEVCONF_ARP_NOTIFY,
IPV4_DEVCONF_ACCEPT_LOCAL,
IPV4_DEVCONF_SRC_VMARK,
IPV4_DEVCONF_PROXY_ARP_PVLAN,
IPV4_DEVCONF_ROUTE_LOCALNET,
IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL,
IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL,
IPV4_DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN,
IPV4_DEVCONF_DROP_UNICAST_IN_L2_MULTICAST,
__IPV4_DEVCONF_MAX
};
#define IPV4_DEVCONF_MAX (__IPV4_DEVCONF_MAX - 1)
#endif /* _UAPI_LINUX_IP_H */