linux/include/net/addrconf.h
Martin KaFai Lau 2dbb9b9e6d bpf: Introduce BPF_PROG_TYPE_SK_REUSEPORT
This patch adds a BPF_PROG_TYPE_SK_REUSEPORT which can select
a SO_REUSEPORT sk from a BPF_MAP_TYPE_REUSEPORT_ARRAY.  Like other
non SK_FILTER/CGROUP_SKB program, it requires CAP_SYS_ADMIN.

BPF_PROG_TYPE_SK_REUSEPORT introduces "struct sk_reuseport_kern"
to store the bpf context instead of using the skb->cb[48].

At the SO_REUSEPORT sk lookup time, it is in the middle of transiting
from a lower layer (ipv4/ipv6) to a upper layer (udp/tcp).  At this
point,  it is not always clear where the bpf context can be appended
in the skb->cb[48] to avoid saving-and-restoring cb[].  Even putting
aside the difference between ipv4-vs-ipv6 and udp-vs-tcp.  It is not
clear if the lower layer is only ipv4 and ipv6 in the future and
will it not touch the cb[] again before transiting to the upper
layer.

For example, in udp_gro_receive(), it uses the 48 byte NAPI_GRO_CB
instead of IP[6]CB and it may still modify the cb[] after calling
the udp[46]_lib_lookup_skb().  Because of the above reason, if
sk->cb is used for the bpf ctx, saving-and-restoring is needed
and likely the whole 48 bytes cb[] has to be saved and restored.

Instead of saving, setting and restoring the cb[], this patch opts
to create a new "struct sk_reuseport_kern" and setting the needed
values in there.

The new BPF_PROG_TYPE_SK_REUSEPORT and "struct sk_reuseport_(kern|md)"
will serve all ipv4/ipv6 + udp/tcp combinations.  There is no protocol
specific usage at this point and it is also inline with the current
sock_reuseport.c implementation (i.e. no protocol specific requirement).

In "struct sk_reuseport_md", this patch exposes data/data_end/len
with semantic similar to other existing usages.  Together
with "bpf_skb_load_bytes()" and "bpf_skb_load_bytes_relative()",
the bpf prog can peek anywhere in the skb.  The "bind_inany" tells
the bpf prog that the reuseport group is bind-ed to a local
INANY address which cannot be learned from skb.

The new "bind_inany" is added to "struct sock_reuseport" which will be
used when running the new "BPF_PROG_TYPE_SK_REUSEPORT" bpf prog in order
to avoid repeating the "bind INANY" test on
"sk_v6_rcv_saddr/sk->sk_rcv_saddr" every time a bpf prog is run.  It can
only be properly initialized when a "sk->sk_reuseport" enabled sk is
adding to a hashtable (i.e. during "reuseport_alloc()" and
"reuseport_add_sock()").

The new "sk_select_reuseport()" is the main helper that the
bpf prog will use to select a SO_REUSEPORT sk.  It is the only function
that can use the new BPF_MAP_TYPE_REUSEPORT_ARRAY.  As mentioned in
the earlier patch, the validity of a selected sk is checked in
run time in "sk_select_reuseport()".  Doing the check in
verification time is difficult and inflexible (consider the map-in-map
use case).  The runtime check is to compare the selected sk's reuseport_id
with the reuseport_id that we want.  This helper will return -EXXX if the
selected sk cannot serve the incoming request (e.g. reuseport_id
not match).  The bpf prog can decide if it wants to do SK_DROP as its
discretion.

When the bpf prog returns SK_PASS, the kernel will check if a
valid sk has been selected (i.e. "reuse_kern->selected_sk != NULL").
If it does , it will use the selected sk.  If not, the kernel
will select one from "reuse->socks[]" (as before this patch).

The SK_DROP and SK_PASS handling logic will be in the next patch.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-11 01:58:46 +02:00

491 lines
14 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ADDRCONF_H
#define _ADDRCONF_H
#define MAX_RTR_SOLICITATIONS -1 /* unlimited */
#define RTR_SOLICITATION_INTERVAL (4*HZ)
#define RTR_SOLICITATION_MAX_INTERVAL (3600*HZ) /* 1 hour */
#define MIN_VALID_LIFETIME (2*3600) /* 2 hours */
#define TEMP_VALID_LIFETIME (7*86400)
#define TEMP_PREFERRED_LIFETIME (86400)
#define REGEN_MAX_RETRY (3)
#define MAX_DESYNC_FACTOR (600)
#define ADDR_CHECK_FREQUENCY (120*HZ)
#define IPV6_MAX_ADDRESSES 16
#define ADDRCONF_TIMER_FUZZ_MINUS (HZ > 50 ? HZ / 50 : 1)
#define ADDRCONF_TIMER_FUZZ (HZ / 4)
#define ADDRCONF_TIMER_FUZZ_MAX (HZ)
#define ADDRCONF_NOTIFY_PRIORITY 0
#include <linux/in.h>
#include <linux/in6.h>
struct prefix_info {
__u8 type;
__u8 length;
__u8 prefix_len;
#if defined(__BIG_ENDIAN_BITFIELD)
__u8 onlink : 1,
autoconf : 1,
reserved : 6;
#elif defined(__LITTLE_ENDIAN_BITFIELD)
__u8 reserved : 6,
autoconf : 1,
onlink : 1;
#else
#error "Please fix <asm/byteorder.h>"
#endif
__be32 valid;
__be32 prefered;
__be32 reserved2;
struct in6_addr prefix;
};
#include <linux/netdevice.h>
#include <net/if_inet6.h>
#include <net/ipv6.h>
struct in6_validator_info {
struct in6_addr i6vi_addr;
struct inet6_dev *i6vi_dev;
struct netlink_ext_ack *extack;
};
struct ifa6_config {
const struct in6_addr *pfx;
unsigned int plen;
const struct in6_addr *peer_pfx;
u32 rt_priority;
u32 ifa_flags;
u32 preferred_lft;
u32 valid_lft;
u16 scope;
};
int addrconf_init(void);
void addrconf_cleanup(void);
int addrconf_add_ifaddr(struct net *net, void __user *arg);
int addrconf_del_ifaddr(struct net *net, void __user *arg);
int addrconf_set_dstaddr(struct net *net, void __user *arg);
int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
const struct net_device *dev, int strict);
int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
const struct net_device *dev, bool skip_dev_check,
int strict, u32 banned_flags);
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr);
#endif
bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
const unsigned int prefix_len,
struct net_device *dev);
int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev);
struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net,
const struct in6_addr *addr,
struct net_device *dev, int strict);
int ipv6_dev_get_saddr(struct net *net, const struct net_device *dev,
const struct in6_addr *daddr, unsigned int srcprefs,
struct in6_addr *saddr);
int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
u32 banned_flags);
int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
u32 banned_flags);
bool inet_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2,
bool match_wildcard);
bool inet_rcv_saddr_any(const struct sock *sk);
void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr);
void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr);
void addrconf_add_linklocal(struct inet6_dev *idev,
const struct in6_addr *addr, u32 flags);
int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
const struct prefix_info *pinfo,
struct inet6_dev *in6_dev,
const struct in6_addr *addr, int addr_type,
u32 addr_flags, bool sllao, bool tokenized,
__u32 valid_lft, u32 prefered_lft);
static inline void addrconf_addr_eui48_base(u8 *eui, const char *const addr)
{
memcpy(eui, addr, 3);
eui[3] = 0xFF;
eui[4] = 0xFE;
memcpy(eui + 5, addr + 3, 3);
}
static inline void addrconf_addr_eui48(u8 *eui, const char *const addr)
{
addrconf_addr_eui48_base(eui, addr);
eui[0] ^= 2;
}
static inline int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
{
if (dev->addr_len != ETH_ALEN)
return -1;
/*
* The zSeries OSA network cards can be shared among various
* OS instances, but the OSA cards have only one MAC address.
* This leads to duplicate address conflicts in conjunction
* with IPv6 if more than one instance uses the same card.
*
* The driver for these cards can deliver a unique 16-bit
* identifier for each instance sharing the same card. It is
* placed instead of 0xFFFE in the interface identifier. The
* "u" bit of the interface identifier is not inverted in this
* case. Hence the resulting interface identifier has local
* scope according to RFC2373.
*/
addrconf_addr_eui48_base(eui, dev->dev_addr);
if (dev->dev_id) {
eui[3] = (dev->dev_id >> 8) & 0xFF;
eui[4] = dev->dev_id & 0xFF;
} else {
eui[0] ^= 2;
}
return 0;
}
static inline unsigned long addrconf_timeout_fixup(u32 timeout,
unsigned int unit)
{
if (timeout == 0xffffffff)
return ~0UL;
/*
* Avoid arithmetic overflow.
* Assuming unit is constant and non-zero, this "if" statement
* will go away on 64bit archs.
*/
if (0xfffffffe > LONG_MAX / unit && timeout > LONG_MAX / unit)
return LONG_MAX / unit;
return timeout;
}
static inline int addrconf_finite_timeout(unsigned long timeout)
{
return ~timeout;
}
/*
* IPv6 Address Label subsystem (addrlabel.c)
*/
int ipv6_addr_label_init(void);
void ipv6_addr_label_cleanup(void);
int ipv6_addr_label_rtnl_register(void);
u32 ipv6_addr_label(struct net *net, const struct in6_addr *addr,
int type, int ifindex);
/*
* multicast prototypes (mcast.c)
*/
int ipv6_sock_mc_join(struct sock *sk, int ifindex,
const struct in6_addr *addr);
int ipv6_sock_mc_drop(struct sock *sk, int ifindex,
const struct in6_addr *addr);
void __ipv6_sock_mc_close(struct sock *sk);
void ipv6_sock_mc_close(struct sock *sk);
bool inet6_mc_check(struct sock *sk, const struct in6_addr *mc_addr,
const struct in6_addr *src_addr);
int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr);
int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr);
int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr);
void ipv6_mc_up(struct inet6_dev *idev);
void ipv6_mc_down(struct inet6_dev *idev);
void ipv6_mc_unmap(struct inet6_dev *idev);
void ipv6_mc_remap(struct inet6_dev *idev);
void ipv6_mc_init_dev(struct inet6_dev *idev);
void ipv6_mc_destroy_dev(struct inet6_dev *idev);
int ipv6_mc_check_mld(struct sk_buff *skb, struct sk_buff **skb_trimmed);
void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp);
bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
const struct in6_addr *src_addr);
void ipv6_mc_dad_complete(struct inet6_dev *idev);
/* A stub used by vxlan module. This is ugly, ideally these
* symbols should be built into the core kernel.
*/
struct ipv6_stub {
int (*ipv6_sock_mc_join)(struct sock *sk, int ifindex,
const struct in6_addr *addr);
int (*ipv6_sock_mc_drop)(struct sock *sk, int ifindex,
const struct in6_addr *addr);
int (*ipv6_dst_lookup)(struct net *net, struct sock *sk,
struct dst_entry **dst, struct flowi6 *fl6);
struct fib6_table *(*fib6_get_table)(struct net *net, u32 id);
struct fib6_info *(*fib6_lookup)(struct net *net, int oif,
struct flowi6 *fl6, int flags);
struct fib6_info *(*fib6_table_lookup)(struct net *net,
struct fib6_table *table,
int oif, struct flowi6 *fl6,
int flags);
struct fib6_info *(*fib6_multipath_select)(const struct net *net,
struct fib6_info *f6i,
struct flowi6 *fl6, int oif,
const struct sk_buff *skb,
int strict);
u32 (*ip6_mtu_from_fib6)(struct fib6_info *f6i, struct in6_addr *daddr,
struct in6_addr *saddr);
void (*udpv6_encap_enable)(void);
void (*ndisc_send_na)(struct net_device *dev, const struct in6_addr *daddr,
const struct in6_addr *solicited_addr,
bool router, bool solicited, bool override, bool inc_opt);
struct neigh_table *nd_tbl;
};
extern const struct ipv6_stub *ipv6_stub __read_mostly;
/* A stub used by bpf helpers. Similarly ugly as ipv6_stub */
struct ipv6_bpf_stub {
int (*inet6_bind)(struct sock *sk, struct sockaddr *uaddr, int addr_len,
bool force_bind_address_no_port, bool with_lock);
};
extern const struct ipv6_bpf_stub *ipv6_bpf_stub __read_mostly;
/*
* identify MLD packets for MLD filter exceptions
*/
static inline bool ipv6_is_mld(struct sk_buff *skb, int nexthdr, int offset)
{
struct icmp6hdr *hdr;
if (nexthdr != IPPROTO_ICMPV6 ||
!pskb_network_may_pull(skb, offset + sizeof(struct icmp6hdr)))
return false;
hdr = (struct icmp6hdr *)(skb_network_header(skb) + offset);
switch (hdr->icmp6_type) {
case ICMPV6_MGM_QUERY:
case ICMPV6_MGM_REPORT:
case ICMPV6_MGM_REDUCTION:
case ICMPV6_MLD2_REPORT:
return true;
default:
break;
}
return false;
}
void addrconf_prefix_rcv(struct net_device *dev,
u8 *opt, int len, bool sllao);
/*
* anycast prototypes (anycast.c)
*/
int ipv6_sock_ac_join(struct sock *sk, int ifindex,
const struct in6_addr *addr);
int ipv6_sock_ac_drop(struct sock *sk, int ifindex,
const struct in6_addr *addr);
void ipv6_sock_ac_close(struct sock *sk);
int __ipv6_dev_ac_inc(struct inet6_dev *idev, const struct in6_addr *addr);
int __ipv6_dev_ac_dec(struct inet6_dev *idev, const struct in6_addr *addr);
void ipv6_ac_destroy_dev(struct inet6_dev *idev);
bool ipv6_chk_acast_addr(struct net *net, struct net_device *dev,
const struct in6_addr *addr);
bool ipv6_chk_acast_addr_src(struct net *net, struct net_device *dev,
const struct in6_addr *addr);
/* Device notifier */
int register_inet6addr_notifier(struct notifier_block *nb);
int unregister_inet6addr_notifier(struct notifier_block *nb);
int inet6addr_notifier_call_chain(unsigned long val, void *v);
int register_inet6addr_validator_notifier(struct notifier_block *nb);
int unregister_inet6addr_validator_notifier(struct notifier_block *nb);
int inet6addr_validator_notifier_call_chain(unsigned long val, void *v);
void inet6_netconf_notify_devconf(struct net *net, int event, int type,
int ifindex, struct ipv6_devconf *devconf);
/**
* __in6_dev_get - get inet6_dev pointer from netdevice
* @dev: network device
*
* Caller must hold rcu_read_lock or RTNL, because this function
* does not take a reference on the inet6_dev.
*/
static inline struct inet6_dev *__in6_dev_get(const struct net_device *dev)
{
return rcu_dereference_rtnl(dev->ip6_ptr);
}
/**
* __in6_dev_get_safely - get inet6_dev pointer from netdevice
* @dev: network device
*
* This is a safer version of __in6_dev_get
*/
static inline struct inet6_dev *__in6_dev_get_safely(const struct net_device *dev)
{
if (likely(dev))
return rcu_dereference_rtnl(dev->ip6_ptr);
else
return NULL;
}
/**
* in6_dev_get - get inet6_dev pointer from netdevice
* @dev: network device
*
* This version can be used in any context, and takes a reference
* on the inet6_dev. Callers must use in6_dev_put() later to
* release this reference.
*/
static inline struct inet6_dev *in6_dev_get(const struct net_device *dev)
{
struct inet6_dev *idev;
rcu_read_lock();
idev = rcu_dereference(dev->ip6_ptr);
if (idev)
refcount_inc(&idev->refcnt);
rcu_read_unlock();
return idev;
}
static inline struct neigh_parms *__in6_dev_nd_parms_get_rcu(const struct net_device *dev)
{
struct inet6_dev *idev = __in6_dev_get(dev);
return idev ? idev->nd_parms : NULL;
}
void in6_dev_finish_destroy(struct inet6_dev *idev);
static inline void in6_dev_put(struct inet6_dev *idev)
{
if (refcount_dec_and_test(&idev->refcnt))
in6_dev_finish_destroy(idev);
}
static inline void in6_dev_put_clear(struct inet6_dev **pidev)
{
struct inet6_dev *idev = *pidev;
if (idev) {
in6_dev_put(idev);
*pidev = NULL;
}
}
static inline void __in6_dev_put(struct inet6_dev *idev)
{
refcount_dec(&idev->refcnt);
}
static inline void in6_dev_hold(struct inet6_dev *idev)
{
refcount_inc(&idev->refcnt);
}
void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp);
static inline void in6_ifa_put(struct inet6_ifaddr *ifp)
{
if (refcount_dec_and_test(&ifp->refcnt))
inet6_ifa_finish_destroy(ifp);
}
static inline void __in6_ifa_put(struct inet6_ifaddr *ifp)
{
refcount_dec(&ifp->refcnt);
}
static inline void in6_ifa_hold(struct inet6_ifaddr *ifp)
{
refcount_inc(&ifp->refcnt);
}
/*
* compute link-local solicited-node multicast address
*/
static inline void addrconf_addr_solict_mult(const struct in6_addr *addr,
struct in6_addr *solicited)
{
ipv6_addr_set(solicited,
htonl(0xFF020000), 0,
htonl(0x1),
htonl(0xFF000000) | addr->s6_addr32[3]);
}
static inline bool ipv6_addr_is_ll_all_nodes(const struct in6_addr *addr)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
__be64 *p = (__be64 *)addr;
return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(1))) == 0UL;
#else
return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
addr->s6_addr32[1] | addr->s6_addr32[2] |
(addr->s6_addr32[3] ^ htonl(0x00000001))) == 0;
#endif
}
static inline bool ipv6_addr_is_ll_all_routers(const struct in6_addr *addr)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
__be64 *p = (__be64 *)addr;
return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) | (p[1] ^ cpu_to_be64(2))) == 0UL;
#else
return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
addr->s6_addr32[1] | addr->s6_addr32[2] |
(addr->s6_addr32[3] ^ htonl(0x00000002))) == 0;
#endif
}
static inline bool ipv6_addr_is_isatap(const struct in6_addr *addr)
{
return (addr->s6_addr32[2] | htonl(0x02000000)) == htonl(0x02005EFE);
}
static inline bool ipv6_addr_is_solict_mult(const struct in6_addr *addr)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
__be64 *p = (__be64 *)addr;
return ((p[0] ^ cpu_to_be64(0xff02000000000000UL)) |
((p[1] ^ cpu_to_be64(0x00000001ff000000UL)) &
cpu_to_be64(0xffffffffff000000UL))) == 0UL;
#else
return ((addr->s6_addr32[0] ^ htonl(0xff020000)) |
addr->s6_addr32[1] |
(addr->s6_addr32[2] ^ htonl(0x00000001)) |
(addr->s6_addr[12] ^ 0xff)) == 0;
#endif
}
#ifdef CONFIG_PROC_FS
int if6_proc_init(void);
void if6_proc_exit(void);
#endif
#endif