linux-stable/include/uapi/linux/ipv6.h
Patrick Rohr 5027d54a9c net: change accept_ra_min_rtr_lft to affect all RA lifetimes
accept_ra_min_rtr_lft only considered the lifetime of the default route
and discarded entire RAs accordingly.

This change renames accept_ra_min_rtr_lft to accept_ra_min_lft, and
applies the value to individual RA sections; in particular, router
lifetime, PIO preferred lifetime, and RIO lifetime. If any of those
lifetimes are lower than the configured value, the specific RA section
is ignored.

In order for the sysctl to be useful to Android, it should really apply
to all lifetimes in the RA, since that is what determines the minimum
frequency at which RAs must be processed by the kernel. Android uses
hardware offloads to drop RAs for a fraction of the minimum of all
lifetimes present in the RA (some networks have very frequent RAs (5s)
with high lifetimes (2h)). Despite this, we have encountered networks
that set the router lifetime to 30s which results in very frequent CPU
wakeups. Instead of disabling IPv6 (and dropping IPv6 ethertype in the
WiFi firmware) entirely on such networks, it seems better to ignore the
misconfigured routers while still processing RAs from other IPv6 routers
on the same network (i.e. to support IoT applications).

The previous implementation dropped the entire RA based on router
lifetime. This turned out to be hard to expand to the other lifetimes
present in the RA in a consistent manner; dropping the entire RA based
on RIO/PIO lifetimes would essentially require parsing the whole thing
twice.

Fixes: 1671bcfd76 ("net: add sysctl accept_ra_min_rtr_lft")
Cc: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Patrick Rohr <prohr@google.com>
Reviewed-by: Maciej Żenczykowski <maze@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230726230701.919212-1-prohr@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-07-28 13:30:51 -07:00

206 lines
4.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#ifndef _UAPI_IPV6_H
#define _UAPI_IPV6_H
#include <linux/libc-compat.h>
#include <linux/types.h>
#include <linux/stddef.h>
#include <linux/in6.h>
#include <asm/byteorder.h>
/* The latest drafts declared increase in minimal mtu up to 1280. */
#define IPV6_MIN_MTU 1280
/*
* Advanced API
* source interface/address selection, source routing, etc...
* *under construction*
*/
#if __UAPI_DEF_IN6_PKTINFO
struct in6_pktinfo {
struct in6_addr ipi6_addr;
int ipi6_ifindex;
};
#endif
#if __UAPI_DEF_IP6_MTUINFO
struct ip6_mtuinfo {
struct sockaddr_in6 ip6m_addr;
__u32 ip6m_mtu;
};
#endif
struct in6_ifreq {
struct in6_addr ifr6_addr;
__u32 ifr6_prefixlen;
int ifr6_ifindex;
};
#define IPV6_SRCRT_STRICT 0x01 /* Deprecated; will be removed */
#define IPV6_SRCRT_TYPE_0 0 /* Deprecated; will be removed */
#define IPV6_SRCRT_TYPE_2 2 /* IPv6 type 2 Routing Header */
#define IPV6_SRCRT_TYPE_3 3 /* RPL Segment Routing with IPv6 */
#define IPV6_SRCRT_TYPE_4 4 /* Segment Routing with IPv6 */
/*
* routing header
*/
struct ipv6_rt_hdr {
__u8 nexthdr;
__u8 hdrlen;
__u8 type;
__u8 segments_left;
/*
* type specific data
* variable length field
*/
};
struct ipv6_opt_hdr {
__u8 nexthdr;
__u8 hdrlen;
/*
* TLV encoded option data follows.
*/
} __attribute__((packed)); /* required for some archs */
#define ipv6_destopt_hdr ipv6_opt_hdr
#define ipv6_hopopt_hdr ipv6_opt_hdr
/* Router Alert option values (RFC2711) */
#define IPV6_OPT_ROUTERALERT_MLD 0x0000 /* MLD(RFC2710) */
/*
* routing header type 0 (used in cmsghdr struct)
*/
struct rt0_hdr {
struct ipv6_rt_hdr rt_hdr;
__u32 reserved;
struct in6_addr addr[];
#define rt0_type rt_hdr.type
};
/*
* routing header type 2
*/
struct rt2_hdr {
struct ipv6_rt_hdr rt_hdr;
__u32 reserved;
struct in6_addr addr;
#define rt2_type rt_hdr.type
};
/*
* home address option in destination options header
*/
struct ipv6_destopt_hao {
__u8 type;
__u8 length;
struct in6_addr addr;
} __attribute__((packed));
/*
* IPv6 fixed header
*
* BEWARE, it is incorrect. The first 4 bits of flow_lbl
* are glued to priority now, forming "class".
*/
struct ipv6hdr {
#if defined(__LITTLE_ENDIAN_BITFIELD)
__u8 priority:4,
version:4;
#elif defined(__BIG_ENDIAN_BITFIELD)
__u8 version:4,
priority:4;
#else
#error "Please fix <asm/byteorder.h>"
#endif
__u8 flow_lbl[3];
__be16 payload_len;
__u8 nexthdr;
__u8 hop_limit;
__struct_group(/* no tag */, addrs, /* no attrs */,
struct in6_addr saddr;
struct in6_addr daddr;
);
};
/* index values for the variables in ipv6_devconf */
enum {
DEVCONF_FORWARDING = 0,
DEVCONF_HOPLIMIT,
DEVCONF_MTU6,
DEVCONF_ACCEPT_RA,
DEVCONF_ACCEPT_REDIRECTS,
DEVCONF_AUTOCONF,
DEVCONF_DAD_TRANSMITS,
DEVCONF_RTR_SOLICITS,
DEVCONF_RTR_SOLICIT_INTERVAL,
DEVCONF_RTR_SOLICIT_DELAY,
DEVCONF_USE_TEMPADDR,
DEVCONF_TEMP_VALID_LFT,
DEVCONF_TEMP_PREFERED_LFT,
DEVCONF_REGEN_MAX_RETRY,
DEVCONF_MAX_DESYNC_FACTOR,
DEVCONF_MAX_ADDRESSES,
DEVCONF_FORCE_MLD_VERSION,
DEVCONF_ACCEPT_RA_DEFRTR,
DEVCONF_ACCEPT_RA_PINFO,
DEVCONF_ACCEPT_RA_RTR_PREF,
DEVCONF_RTR_PROBE_INTERVAL,
DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN,
DEVCONF_PROXY_NDP,
DEVCONF_OPTIMISTIC_DAD,
DEVCONF_ACCEPT_SOURCE_ROUTE,
DEVCONF_MC_FORWARDING,
DEVCONF_DISABLE_IPV6,
DEVCONF_ACCEPT_DAD,
DEVCONF_FORCE_TLLAO,
DEVCONF_NDISC_NOTIFY,
DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL,
DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL,
DEVCONF_SUPPRESS_FRAG_NDISC,
DEVCONF_ACCEPT_RA_FROM_LOCAL,
DEVCONF_USE_OPTIMISTIC,
DEVCONF_ACCEPT_RA_MTU,
DEVCONF_STABLE_SECRET,
DEVCONF_USE_OIF_ADDRS_ONLY,
DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT,
DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN,
DEVCONF_DROP_UNICAST_IN_L2_MULTICAST,
DEVCONF_DROP_UNSOLICITED_NA,
DEVCONF_KEEP_ADDR_ON_DOWN,
DEVCONF_RTR_SOLICIT_MAX_INTERVAL,
DEVCONF_SEG6_ENABLED,
DEVCONF_SEG6_REQUIRE_HMAC,
DEVCONF_ENHANCED_DAD,
DEVCONF_ADDR_GEN_MODE,
DEVCONF_DISABLE_POLICY,
DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN,
DEVCONF_NDISC_TCLASS,
DEVCONF_RPL_SEG_ENABLED,
DEVCONF_RA_DEFRTR_METRIC,
DEVCONF_IOAM6_ENABLED,
DEVCONF_IOAM6_ID,
DEVCONF_IOAM6_ID_WIDE,
DEVCONF_NDISC_EVICT_NOCARRIER,
DEVCONF_ACCEPT_UNTRACKED_NA,
DEVCONF_ACCEPT_RA_MIN_LFT,
DEVCONF_MAX
};
#endif /* _UAPI_IPV6_H */