diff options
Diffstat (limited to 'include/net/ipv6.h')
-rw-r--r-- | include/net/ipv6.h | 1269 |
1 files changed, 1269 insertions, 0 deletions
diff --git a/include/net/ipv6.h b/include/net/ipv6.h new file mode 100644 index 000000000..47d644de0 --- /dev/null +++ b/include/net/ipv6.h @@ -0,0 +1,1269 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Linux INET6 implementation + * + * Authors: + * Pedro Roque <roque@di.fc.ul.pt> + */ + +#ifndef _NET_IPV6_H +#define _NET_IPV6_H + +#include <linux/ipv6.h> +#include <linux/hardirq.h> +#include <linux/jhash.h> +#include <linux/refcount.h> +#include <linux/jump_label_ratelimit.h> +#include <net/if_inet6.h> +#include <net/ndisc.h> +#include <net/flow.h> +#include <net/flow_dissector.h> +#include <net/snmp.h> +#include <net/netns/hash.h> + +#define SIN6_LEN_RFC2133 24 + +#define IPV6_MAXPLEN 65535 + +/* + * NextHeader field of IPv6 header + */ + +#define NEXTHDR_HOP 0 /* Hop-by-hop option header. */ +#define NEXTHDR_TCP 6 /* TCP segment. */ +#define NEXTHDR_UDP 17 /* UDP message. */ +#define NEXTHDR_IPV6 41 /* IPv6 in IPv6 */ +#define NEXTHDR_ROUTING 43 /* Routing header. */ +#define NEXTHDR_FRAGMENT 44 /* Fragmentation/reassembly header. */ +#define NEXTHDR_GRE 47 /* GRE header. */ +#define NEXTHDR_ESP 50 /* Encapsulating security payload. */ +#define NEXTHDR_AUTH 51 /* Authentication header. */ +#define NEXTHDR_ICMP 58 /* ICMP for IPv6. */ +#define NEXTHDR_NONE 59 /* No next header */ +#define NEXTHDR_DEST 60 /* Destination options header. */ +#define NEXTHDR_SCTP 132 /* SCTP message. */ +#define NEXTHDR_MOBILITY 135 /* Mobility header. */ + +#define NEXTHDR_MAX 255 + +#define IPV6_DEFAULT_HOPLIMIT 64 +#define IPV6_DEFAULT_MCASTHOPS 1 + +/* Limits on Hop-by-Hop and Destination options. + * + * Per RFC8200 there is no limit on the maximum number or lengths of options in + * Hop-by-Hop or Destination options other then the packet must fit in an MTU. + * We allow configurable limits in order to mitigate potential denial of + * service attacks. + * + * There are three limits that may be set: + * - Limit the number of options in a Hop-by-Hop or Destination options + * extension header + * - Limit the byte length of a Hop-by-Hop or Destination options extension + * header + * - Disallow unknown options + * + * The limits are expressed in corresponding sysctls: + * + * ipv6.sysctl.max_dst_opts_cnt + * ipv6.sysctl.max_hbh_opts_cnt + * ipv6.sysctl.max_dst_opts_len + * ipv6.sysctl.max_hbh_opts_len + * + * max_*_opts_cnt is the number of TLVs that are allowed for Destination + * options or Hop-by-Hop options. If the number is less than zero then unknown + * TLVs are disallowed and the number of known options that are allowed is the + * absolute value. Setting the value to INT_MAX indicates no limit. + * + * max_*_opts_len is the length limit in bytes of a Destination or + * Hop-by-Hop options extension header. Setting the value to INT_MAX + * indicates no length limit. + * + * If a limit is exceeded when processing an extension header the packet is + * silently discarded. + */ + +/* Default limits for Hop-by-Hop and Destination options */ +#define IP6_DEFAULT_MAX_DST_OPTS_CNT 8 +#define IP6_DEFAULT_MAX_HBH_OPTS_CNT 8 +#define IP6_DEFAULT_MAX_DST_OPTS_LEN INT_MAX /* No limit */ +#define IP6_DEFAULT_MAX_HBH_OPTS_LEN INT_MAX /* No limit */ + +/* + * Addr type + * + * type - unicast | multicast + * scope - local | site | global + * v4 - compat + * v4mapped + * any + * loopback + */ + +#define IPV6_ADDR_ANY 0x0000U + +#define IPV6_ADDR_UNICAST 0x0001U +#define IPV6_ADDR_MULTICAST 0x0002U + +#define IPV6_ADDR_LOOPBACK 0x0010U +#define IPV6_ADDR_LINKLOCAL 0x0020U +#define IPV6_ADDR_SITELOCAL 0x0040U + +#define IPV6_ADDR_COMPATv4 0x0080U + +#define IPV6_ADDR_SCOPE_MASK 0x00f0U + +#define IPV6_ADDR_MAPPED 0x1000U + +/* + * Addr scopes + */ +#define IPV6_ADDR_MC_SCOPE(a) \ + ((a)->s6_addr[1] & 0x0f) /* nonstandard */ +#define __IPV6_ADDR_SCOPE_INVALID -1 +#define IPV6_ADDR_SCOPE_NODELOCAL 0x01 +#define IPV6_ADDR_SCOPE_LINKLOCAL 0x02 +#define IPV6_ADDR_SCOPE_SITELOCAL 0x05 +#define IPV6_ADDR_SCOPE_ORGLOCAL 0x08 +#define IPV6_ADDR_SCOPE_GLOBAL 0x0e + +/* + * Addr flags + */ +#define IPV6_ADDR_MC_FLAG_TRANSIENT(a) \ + ((a)->s6_addr[1] & 0x10) +#define IPV6_ADDR_MC_FLAG_PREFIX(a) \ + ((a)->s6_addr[1] & 0x20) +#define IPV6_ADDR_MC_FLAG_RENDEZVOUS(a) \ + ((a)->s6_addr[1] & 0x40) + +/* + * fragmentation header + */ + +struct frag_hdr { + __u8 nexthdr; + __u8 reserved; + __be16 frag_off; + __be32 identification; +}; + +#define IP6_MF 0x0001 +#define IP6_OFFSET 0xFFF8 + +struct ip6_fraglist_iter { + struct ipv6hdr *tmp_hdr; + struct sk_buff *frag; + int offset; + unsigned int hlen; + __be32 frag_id; + u8 nexthdr; +}; + +int ip6_fraglist_init(struct sk_buff *skb, unsigned int hlen, u8 *prevhdr, + u8 nexthdr, __be32 frag_id, + struct ip6_fraglist_iter *iter); +void ip6_fraglist_prepare(struct sk_buff *skb, struct ip6_fraglist_iter *iter); + +static inline struct sk_buff *ip6_fraglist_next(struct ip6_fraglist_iter *iter) +{ + struct sk_buff *skb = iter->frag; + + iter->frag = skb->next; + skb_mark_not_on_list(skb); + + return skb; +} + +struct ip6_frag_state { + u8 *prevhdr; + unsigned int hlen; + unsigned int mtu; + unsigned int left; + int offset; + int ptr; + int hroom; + int troom; + __be32 frag_id; + u8 nexthdr; +}; + +void ip6_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int mtu, + unsigned short needed_tailroom, int hdr_room, u8 *prevhdr, + u8 nexthdr, __be32 frag_id, struct ip6_frag_state *state); +struct sk_buff *ip6_frag_next(struct sk_buff *skb, + struct ip6_frag_state *state); + +#define IP6_REPLY_MARK(net, mark) \ + ((net)->ipv6.sysctl.fwmark_reflect ? (mark) : 0) + +#include <net/sock.h> + +/* sysctls */ +extern int sysctl_mld_max_msf; +extern int sysctl_mld_qrv; + +#define _DEVINC(net, statname, mod, idev, field) \ +({ \ + struct inet6_dev *_idev = (idev); \ + if (likely(_idev != NULL)) \ + mod##SNMP_INC_STATS64((_idev)->stats.statname, (field));\ + mod##SNMP_INC_STATS64((net)->mib.statname##_statistics, (field));\ +}) + +/* per device counters are atomic_long_t */ +#define _DEVINCATOMIC(net, statname, mod, idev, field) \ +({ \ + struct inet6_dev *_idev = (idev); \ + if (likely(_idev != NULL)) \ + SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \ + mod##SNMP_INC_STATS((net)->mib.statname##_statistics, (field));\ +}) + +/* per device and per net counters are atomic_long_t */ +#define _DEVINC_ATOMIC_ATOMIC(net, statname, idev, field) \ +({ \ + struct inet6_dev *_idev = (idev); \ + if (likely(_idev != NULL)) \ + SNMP_INC_STATS_ATOMIC_LONG((_idev)->stats.statname##dev, (field)); \ + SNMP_INC_STATS_ATOMIC_LONG((net)->mib.statname##_statistics, (field));\ +}) + +#define _DEVADD(net, statname, mod, idev, field, val) \ +({ \ + struct inet6_dev *_idev = (idev); \ + if (likely(_idev != NULL)) \ + mod##SNMP_ADD_STATS((_idev)->stats.statname, (field), (val)); \ + mod##SNMP_ADD_STATS((net)->mib.statname##_statistics, (field), (val));\ +}) + +#define _DEVUPD(net, statname, mod, idev, field, val) \ +({ \ + struct inet6_dev *_idev = (idev); \ + if (likely(_idev != NULL)) \ + mod##SNMP_UPD_PO_STATS((_idev)->stats.statname, field, (val)); \ + mod##SNMP_UPD_PO_STATS((net)->mib.statname##_statistics, field, (val));\ +}) + +/* MIBs */ + +#define IP6_INC_STATS(net, idev,field) \ + _DEVINC(net, ipv6, , idev, field) +#define __IP6_INC_STATS(net, idev,field) \ + _DEVINC(net, ipv6, __, idev, field) +#define IP6_ADD_STATS(net, idev,field,val) \ + _DEVADD(net, ipv6, , idev, field, val) +#define __IP6_ADD_STATS(net, idev,field,val) \ + _DEVADD(net, ipv6, __, idev, field, val) +#define IP6_UPD_PO_STATS(net, idev,field,val) \ + _DEVUPD(net, ipv6, , idev, field, val) +#define __IP6_UPD_PO_STATS(net, idev,field,val) \ + _DEVUPD(net, ipv6, __, idev, field, val) +#define ICMP6_INC_STATS(net, idev, field) \ + _DEVINCATOMIC(net, icmpv6, , idev, field) +#define __ICMP6_INC_STATS(net, idev, field) \ + _DEVINCATOMIC(net, icmpv6, __, idev, field) + +#define ICMP6MSGOUT_INC_STATS(net, idev, field) \ + _DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field +256) +#define ICMP6MSGIN_INC_STATS(net, idev, field) \ + _DEVINC_ATOMIC_ATOMIC(net, icmpv6msg, idev, field) + +struct ip6_ra_chain { + struct ip6_ra_chain *next; + struct sock *sk; + int sel; + void (*destructor)(struct sock *); +}; + +extern struct ip6_ra_chain *ip6_ra_chain; +extern rwlock_t ip6_ra_lock; + +/* + This structure is prepared by protocol, when parsing + ancillary data and passed to IPv6. + */ + +struct ipv6_txoptions { + refcount_t refcnt; + /* Length of this structure */ + int tot_len; + + /* length of extension headers */ + + __u16 opt_flen; /* after fragment hdr */ + __u16 opt_nflen; /* before fragment hdr */ + + struct ipv6_opt_hdr *hopopt; + struct ipv6_opt_hdr *dst0opt; + struct ipv6_rt_hdr *srcrt; /* Routing Header */ + struct ipv6_opt_hdr *dst1opt; + struct rcu_head rcu; + /* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */ +}; + +/* flowlabel_reflect sysctl values */ +enum flowlabel_reflect { + FLOWLABEL_REFLECT_ESTABLISHED = 1, + FLOWLABEL_REFLECT_TCP_RESET = 2, + FLOWLABEL_REFLECT_ICMPV6_ECHO_REPLIES = 4, +}; + +struct ip6_flowlabel { + struct ip6_flowlabel __rcu *next; + __be32 label; + atomic_t users; + struct in6_addr dst; + struct ipv6_txoptions *opt; + unsigned long linger; + struct rcu_head rcu; + u8 share; + union { + struct pid *pid; + kuid_t uid; + } owner; + unsigned long lastuse; + unsigned long expires; + struct net *fl_net; +}; + +#define IPV6_FLOWINFO_MASK cpu_to_be32(0x0FFFFFFF) +#define IPV6_FLOWLABEL_MASK cpu_to_be32(0x000FFFFF) +#define IPV6_FLOWLABEL_STATELESS_FLAG cpu_to_be32(0x00080000) + +#define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK) +#define IPV6_TCLASS_SHIFT 20 + +struct ipv6_fl_socklist { + struct ipv6_fl_socklist __rcu *next; + struct ip6_flowlabel *fl; + struct rcu_head rcu; +}; + +struct ipcm6_cookie { + struct sockcm_cookie sockc; + __s16 hlimit; + __s16 tclass; + __s8 dontfrag; + struct ipv6_txoptions *opt; + __u16 gso_size; +}; + +static inline void ipcm6_init(struct ipcm6_cookie *ipc6) +{ + *ipc6 = (struct ipcm6_cookie) { + .hlimit = -1, + .tclass = -1, + .dontfrag = -1, + }; +} + +static inline void ipcm6_init_sk(struct ipcm6_cookie *ipc6, + const struct ipv6_pinfo *np) +{ + *ipc6 = (struct ipcm6_cookie) { + .hlimit = -1, + .tclass = np->tclass, + .dontfrag = np->dontfrag, + }; +} + +static inline struct ipv6_txoptions *txopt_get(const struct ipv6_pinfo *np) +{ + struct ipv6_txoptions *opt; + + rcu_read_lock(); + opt = rcu_dereference(np->opt); + if (opt) { + if (!refcount_inc_not_zero(&opt->refcnt)) + opt = NULL; + else + opt = rcu_pointer_handoff(opt); + } + rcu_read_unlock(); + return opt; +} + +static inline void txopt_put(struct ipv6_txoptions *opt) +{ + if (opt && refcount_dec_and_test(&opt->refcnt)) + kfree_rcu(opt, rcu); +} + +#if IS_ENABLED(CONFIG_IPV6) +struct ip6_flowlabel *__fl6_sock_lookup(struct sock *sk, __be32 label); + +extern struct static_key_false_deferred ipv6_flowlabel_exclusive; +static inline struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, + __be32 label) +{ + if (static_branch_unlikely(&ipv6_flowlabel_exclusive.key) && + READ_ONCE(sock_net(sk)->ipv6.flowlabel_has_excl)) + return __fl6_sock_lookup(sk, label) ? : ERR_PTR(-ENOENT); + + return NULL; +} +#endif + +struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space, + struct ip6_flowlabel *fl, + struct ipv6_txoptions *fopt); +void fl6_free_socklist(struct sock *sk); +int ipv6_flowlabel_opt(struct sock *sk, sockptr_t optval, int optlen); +int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq, + int flags); +int ip6_flowlabel_init(void); +void ip6_flowlabel_cleanup(void); +bool ip6_autoflowlabel(struct net *net, const struct ipv6_pinfo *np); + +static inline void fl6_sock_release(struct ip6_flowlabel *fl) +{ + if (fl) + atomic_dec(&fl->users); +} + +void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info); + +void icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6, + struct icmp6hdr *thdr, int len); + +int ip6_ra_control(struct sock *sk, int sel); + +int ipv6_parse_hopopts(struct sk_buff *skb); + +struct ipv6_txoptions *ipv6_dup_options(struct sock *sk, + struct ipv6_txoptions *opt); +struct ipv6_txoptions *ipv6_renew_options(struct sock *sk, + struct ipv6_txoptions *opt, + int newtype, + struct ipv6_opt_hdr *newopt); +struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space, + struct ipv6_txoptions *opt); + +bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb, + const struct inet6_skb_parm *opt); +struct ipv6_txoptions *ipv6_update_options(struct sock *sk, + struct ipv6_txoptions *opt); + +static inline bool ipv6_accept_ra(struct inet6_dev *idev) +{ + /* If forwarding is enabled, RA are not accepted unless the special + * hybrid mode (accept_ra=2) is enabled. + */ + return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 : + idev->cnf.accept_ra; +} + +#define IPV6_FRAG_HIGH_THRESH (4 * 1024*1024) /* 4194304 */ +#define IPV6_FRAG_LOW_THRESH (3 * 1024*1024) /* 3145728 */ +#define IPV6_FRAG_TIMEOUT (60 * HZ) /* 60 seconds */ + +int __ipv6_addr_type(const struct in6_addr *addr); +static inline int ipv6_addr_type(const struct in6_addr *addr) +{ + return __ipv6_addr_type(addr) & 0xffff; +} + +static inline int ipv6_addr_scope(const struct in6_addr *addr) +{ + return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK; +} + +static inline int __ipv6_addr_src_scope(int type) +{ + return (type == IPV6_ADDR_ANY) ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16); +} + +static inline int ipv6_addr_src_scope(const struct in6_addr *addr) +{ + return __ipv6_addr_src_scope(__ipv6_addr_type(addr)); +} + +static inline bool __ipv6_addr_needs_scope_id(int type) +{ + return type & IPV6_ADDR_LINKLOCAL || + (type & IPV6_ADDR_MULTICAST && + (type & (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL))); +} + +static inline __u32 ipv6_iface_scope_id(const struct in6_addr *addr, int iface) +{ + return __ipv6_addr_needs_scope_id(__ipv6_addr_type(addr)) ? iface : 0; +} + +static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2) +{ + return memcmp(a1, a2, sizeof(struct in6_addr)); +} + +static inline bool +ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m, + const struct in6_addr *a2) +{ +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 + const unsigned long *ul1 = (const unsigned long *)a1; + const unsigned long *ulm = (const unsigned long *)m; + const unsigned long *ul2 = (const unsigned long *)a2; + + return !!(((ul1[0] ^ ul2[0]) & ulm[0]) | + ((ul1[1] ^ ul2[1]) & ulm[1])); +#else + return !!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) | + ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) | + ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) | + ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3])); +#endif +} + +static inline void ipv6_addr_prefix(struct in6_addr *pfx, + const struct in6_addr *addr, + int plen) +{ + /* caller must guarantee 0 <= plen <= 128 */ + int o = plen >> 3, + b = plen & 0x7; + + memset(pfx->s6_addr, 0, sizeof(pfx->s6_addr)); + memcpy(pfx->s6_addr, addr, o); + if (b != 0) + pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b); +} + +static inline void ipv6_addr_prefix_copy(struct in6_addr *addr, + const struct in6_addr *pfx, + int plen) +{ + /* caller must guarantee 0 <= plen <= 128 */ + int o = plen >> 3, + b = plen & 0x7; + + memcpy(addr->s6_addr, pfx, o); + if (b != 0) { + addr->s6_addr[o] &= ~(0xff00 >> b); + addr->s6_addr[o] |= (pfx->s6_addr[o] & (0xff00 >> b)); + } +} + +static inline void __ipv6_addr_set_half(__be32 *addr, + __be32 wh, __be32 wl) +{ +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 +#if defined(__BIG_ENDIAN) + if (__builtin_constant_p(wh) && __builtin_constant_p(wl)) { + *(__force u64 *)addr = ((__force u64)(wh) << 32 | (__force u64)(wl)); + return; + } +#elif defined(__LITTLE_ENDIAN) + if (__builtin_constant_p(wl) && __builtin_constant_p(wh)) { + *(__force u64 *)addr = ((__force u64)(wl) << 32 | (__force u64)(wh)); + return; + } +#endif +#endif + addr[0] = wh; + addr[1] = wl; +} + +static inline void ipv6_addr_set(struct in6_addr *addr, + __be32 w1, __be32 w2, + __be32 w3, __be32 w4) +{ + __ipv6_addr_set_half(&addr->s6_addr32[0], w1, w2); + __ipv6_addr_set_half(&addr->s6_addr32[2], w3, w4); +} + +static inline bool ipv6_addr_equal(const struct in6_addr *a1, + const struct in6_addr *a2) +{ +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 + const unsigned long *ul1 = (const unsigned long *)a1; + const unsigned long *ul2 = (const unsigned long *)a2; + + return ((ul1[0] ^ ul2[0]) | (ul1[1] ^ ul2[1])) == 0UL; +#else + return ((a1->s6_addr32[0] ^ a2->s6_addr32[0]) | + (a1->s6_addr32[1] ^ a2->s6_addr32[1]) | + (a1->s6_addr32[2] ^ a2->s6_addr32[2]) | + (a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0; +#endif +} + +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 +static inline bool __ipv6_prefix_equal64_half(const __be64 *a1, + const __be64 *a2, + unsigned int len) +{ + if (len && ((*a1 ^ *a2) & cpu_to_be64((~0UL) << (64 - len)))) + return false; + return true; +} + +static inline bool ipv6_prefix_equal(const struct in6_addr *addr1, + const struct in6_addr *addr2, + unsigned int prefixlen) +{ + const __be64 *a1 = (const __be64 *)addr1; + const __be64 *a2 = (const __be64 *)addr2; + + if (prefixlen >= 64) { + if (a1[0] ^ a2[0]) + return false; + return __ipv6_prefix_equal64_half(a1 + 1, a2 + 1, prefixlen - 64); + } + return __ipv6_prefix_equal64_half(a1, a2, prefixlen); +} +#else +static inline bool ipv6_prefix_equal(const struct in6_addr *addr1, + const struct in6_addr *addr2, + unsigned int prefixlen) +{ + const __be32 *a1 = addr1->s6_addr32; + const __be32 *a2 = addr2->s6_addr32; + unsigned int pdw, pbi; + + /* check complete u32 in prefix */ + pdw = prefixlen >> 5; + if (pdw && memcmp(a1, a2, pdw << 2)) + return false; + + /* check incomplete u32 in prefix */ + pbi = prefixlen & 0x1f; + if (pbi && ((a1[pdw] ^ a2[pdw]) & htonl((0xffffffff) << (32 - pbi)))) + return false; + + return true; +} +#endif + +static inline bool ipv6_addr_any(const struct in6_addr *a) +{ +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 + const unsigned long *ul = (const unsigned long *)a; + + return (ul[0] | ul[1]) == 0UL; +#else + return (a->s6_addr32[0] | a->s6_addr32[1] | + a->s6_addr32[2] | a->s6_addr32[3]) == 0; +#endif +} + +static inline u32 ipv6_addr_hash(const struct in6_addr *a) +{ +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 + const unsigned long *ul = (const unsigned long *)a; + unsigned long x = ul[0] ^ ul[1]; + + return (u32)(x ^ (x >> 32)); +#else + return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^ + a->s6_addr32[2] ^ a->s6_addr32[3]); +#endif +} + +/* more secured version of ipv6_addr_hash() */ +static inline u32 __ipv6_addr_jhash(const struct in6_addr *a, const u32 initval) +{ + return jhash2((__force const u32 *)a->s6_addr32, + ARRAY_SIZE(a->s6_addr32), initval); +} + +static inline bool ipv6_addr_loopback(const struct in6_addr *a) +{ +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 + const __be64 *be = (const __be64 *)a; + + return (be[0] | (be[1] ^ cpu_to_be64(1))) == 0UL; +#else + return (a->s6_addr32[0] | a->s6_addr32[1] | + a->s6_addr32[2] | (a->s6_addr32[3] ^ cpu_to_be32(1))) == 0; +#endif +} + +/* + * Note that we must __force cast these to unsigned long to make sparse happy, + * since all of the endian-annotated types are fixed size regardless of arch. + */ +static inline bool ipv6_addr_v4mapped(const struct in6_addr *a) +{ + return ( +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 + *(unsigned long *)a | +#else + (__force unsigned long)(a->s6_addr32[0] | a->s6_addr32[1]) | +#endif + (__force unsigned long)(a->s6_addr32[2] ^ + cpu_to_be32(0x0000ffff))) == 0UL; +} + +static inline bool ipv6_addr_v4mapped_loopback(const struct in6_addr *a) +{ + return ipv6_addr_v4mapped(a) && ipv4_is_loopback(a->s6_addr32[3]); +} + +static inline u32 ipv6_portaddr_hash(const struct net *net, + const struct in6_addr *addr6, + unsigned int port) +{ + unsigned int hash, mix = net_hash_mix(net); + + if (ipv6_addr_any(addr6)) + hash = jhash_1word(0, mix); + else if (ipv6_addr_v4mapped(addr6)) + hash = jhash_1word((__force u32)addr6->s6_addr32[3], mix); + else + hash = jhash2((__force u32 *)addr6->s6_addr32, 4, mix); + + return hash ^ port; +} + +/* + * Check for a RFC 4843 ORCHID address + * (Overlay Routable Cryptographic Hash Identifiers) + */ +static inline bool ipv6_addr_orchid(const struct in6_addr *a) +{ + return (a->s6_addr32[0] & htonl(0xfffffff0)) == htonl(0x20010010); +} + +static inline bool ipv6_addr_is_multicast(const struct in6_addr *addr) +{ + return (addr->s6_addr32[0] & htonl(0xFF000000)) == htonl(0xFF000000); +} + +static inline void ipv6_addr_set_v4mapped(const __be32 addr, + struct in6_addr *v4mapped) +{ + ipv6_addr_set(v4mapped, + 0, 0, + htonl(0x0000FFFF), + addr); +} + +/* + * find the first different bit between two addresses + * length of address must be a multiple of 32bits + */ +static inline int __ipv6_addr_diff32(const void *token1, const void *token2, int addrlen) +{ + const __be32 *a1 = token1, *a2 = token2; + int i; + + addrlen >>= 2; + + for (i = 0; i < addrlen; i++) { + __be32 xb = a1[i] ^ a2[i]; + if (xb) + return i * 32 + 31 - __fls(ntohl(xb)); + } + + /* + * we should *never* get to this point since that + * would mean the addrs are equal + * + * However, we do get to it 8) And exacly, when + * addresses are equal 8) + * + * ip route add 1111::/128 via ... + * ip route add 1111::/64 via ... + * and we are here. + * + * Ideally, this function should stop comparison + * at prefix length. It does not, but it is still OK, + * if returned value is greater than prefix length. + * --ANK (980803) + */ + return addrlen << 5; +} + +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 +static inline int __ipv6_addr_diff64(const void *token1, const void *token2, int addrlen) +{ + const __be64 *a1 = token1, *a2 = token2; + int i; + + addrlen >>= 3; + + for (i = 0; i < addrlen; i++) { + __be64 xb = a1[i] ^ a2[i]; + if (xb) + return i * 64 + 63 - __fls(be64_to_cpu(xb)); + } + + return addrlen << 6; +} +#endif + +static inline int __ipv6_addr_diff(const void *token1, const void *token2, int addrlen) +{ +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64 + if (__builtin_constant_p(addrlen) && !(addrlen & 7)) + return __ipv6_addr_diff64(token1, token2, addrlen); +#endif + return __ipv6_addr_diff32(token1, token2, addrlen); +} + +static inline int ipv6_addr_diff(const struct in6_addr *a1, const struct in6_addr *a2) +{ + return __ipv6_addr_diff(a1, a2, sizeof(struct in6_addr)); +} + +__be32 ipv6_select_ident(struct net *net, + const struct in6_addr *daddr, + const struct in6_addr *saddr); +__be32 ipv6_proxy_select_ident(struct net *net, struct sk_buff *skb); + +int ip6_dst_hoplimit(struct dst_entry *dst); + +static inline int ip6_sk_dst_hoplimit(struct ipv6_pinfo *np, struct flowi6 *fl6, + struct dst_entry *dst) +{ + int hlimit; + + if (ipv6_addr_is_multicast(&fl6->daddr)) + hlimit = np->mcast_hops; + else + hlimit = np->hop_limit; + if (hlimit < 0) + hlimit = ip6_dst_hoplimit(dst); + return hlimit; +} + +/* copy IPv6 saddr & daddr to flow_keys, possibly using 64bit load/store + * Equivalent to : flow->v6addrs.src = iph->saddr; + * flow->v6addrs.dst = iph->daddr; + */ +static inline void iph_to_flow_copy_v6addrs(struct flow_keys *flow, + const struct ipv6hdr *iph) +{ + BUILD_BUG_ON(offsetof(typeof(flow->addrs), v6addrs.dst) != + offsetof(typeof(flow->addrs), v6addrs.src) + + sizeof(flow->addrs.v6addrs.src)); + memcpy(&flow->addrs.v6addrs, &iph->addrs, sizeof(flow->addrs.v6addrs)); + flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS; +} + +#if IS_ENABLED(CONFIG_IPV6) + +static inline bool ipv6_can_nonlocal_bind(struct net *net, + struct inet_sock *inet) +{ + return net->ipv6.sysctl.ip_nonlocal_bind || + inet->freebind || inet->transparent; +} + +/* Sysctl settings for net ipv6.auto_flowlabels */ +#define IP6_AUTO_FLOW_LABEL_OFF 0 +#define IP6_AUTO_FLOW_LABEL_OPTOUT 1 +#define IP6_AUTO_FLOW_LABEL_OPTIN 2 +#define IP6_AUTO_FLOW_LABEL_FORCED 3 + +#define IP6_AUTO_FLOW_LABEL_MAX IP6_AUTO_FLOW_LABEL_FORCED + +#define IP6_DEFAULT_AUTO_FLOW_LABELS IP6_AUTO_FLOW_LABEL_OPTOUT + +static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb, + __be32 flowlabel, bool autolabel, + struct flowi6 *fl6) +{ + u32 hash; + + /* @flowlabel may include more than a flow label, eg, the traffic class. + * Here we want only the flow label value. + */ + flowlabel &= IPV6_FLOWLABEL_MASK; + + if (flowlabel || + net->ipv6.sysctl.auto_flowlabels == IP6_AUTO_FLOW_LABEL_OFF || + (!autolabel && + net->ipv6.sysctl.auto_flowlabels != IP6_AUTO_FLOW_LABEL_FORCED)) + return flowlabel; + + hash = skb_get_hash_flowi6(skb, fl6); + + /* Since this is being sent on the wire obfuscate hash a bit + * to minimize possbility that any useful information to an + * attacker is leaked. Only lower 20 bits are relevant. + */ + hash = rol32(hash, 16); + + flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK; + + if (net->ipv6.sysctl.flowlabel_state_ranges) + flowlabel |= IPV6_FLOWLABEL_STATELESS_FLAG; + + return flowlabel; +} + +static inline int ip6_default_np_autolabel(struct net *net) +{ + switch (net->ipv6.sysctl.auto_flowlabels) { + case IP6_AUTO_FLOW_LABEL_OFF: + case IP6_AUTO_FLOW_LABEL_OPTIN: + default: + return 0; + case IP6_AUTO_FLOW_LABEL_OPTOUT: + case IP6_AUTO_FLOW_LABEL_FORCED: + return 1; + } +} +#else +static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb, + __be32 flowlabel, bool autolabel, + struct flowi6 *fl6) +{ + return flowlabel; +} +static inline int ip6_default_np_autolabel(struct net *net) +{ + return 0; +} +#endif + +#if IS_ENABLED(CONFIG_IPV6) +static inline int ip6_multipath_hash_policy(const struct net *net) +{ + return net->ipv6.sysctl.multipath_hash_policy; +} +#else +static inline int ip6_multipath_hash_policy(const struct net *net) +{ + return 0; +} +#endif + +/* + * Header manipulation + */ +static inline void ip6_flow_hdr(struct ipv6hdr *hdr, unsigned int tclass, + __be32 flowlabel) +{ + *(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | flowlabel; +} + +static inline __be32 ip6_flowinfo(const struct ipv6hdr *hdr) +{ + return *(__be32 *)hdr & IPV6_FLOWINFO_MASK; +} + +static inline __be32 ip6_flowlabel(const struct ipv6hdr *hdr) +{ + return *(__be32 *)hdr & IPV6_FLOWLABEL_MASK; +} + +static inline u8 ip6_tclass(__be32 flowinfo) +{ + return ntohl(flowinfo & IPV6_TCLASS_MASK) >> IPV6_TCLASS_SHIFT; +} + +static inline __be32 ip6_make_flowinfo(unsigned int tclass, __be32 flowlabel) +{ + return htonl(tclass << IPV6_TCLASS_SHIFT) | flowlabel; +} + +static inline __be32 flowi6_get_flowlabel(const struct flowi6 *fl6) +{ + return fl6->flowlabel & IPV6_FLOWLABEL_MASK; +} + +/* + * Prototypes exported by ipv6 + */ + +/* + * rcv function (called from netdevice level) + */ + +int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, + struct packet_type *pt, struct net_device *orig_dev); +void ipv6_list_rcv(struct list_head *head, struct packet_type *pt, + struct net_device *orig_dev); + +int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb); + +/* + * upper-layer output functions + */ +int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, + __u32 mark, struct ipv6_txoptions *opt, int tclass, u32 priority); + +int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr); + +int ip6_append_data(struct sock *sk, + int getfrag(void *from, char *to, int offset, int len, + int odd, struct sk_buff *skb), + void *from, int length, int transhdrlen, + struct ipcm6_cookie *ipc6, struct flowi6 *fl6, + struct rt6_info *rt, unsigned int flags); + +int ip6_push_pending_frames(struct sock *sk); + +void ip6_flush_pending_frames(struct sock *sk); + +int ip6_send_skb(struct sk_buff *skb); + +struct sk_buff *__ip6_make_skb(struct sock *sk, struct sk_buff_head *queue, + struct inet_cork_full *cork, + struct inet6_cork *v6_cork); +struct sk_buff *ip6_make_skb(struct sock *sk, + int getfrag(void *from, char *to, int offset, + int len, int odd, struct sk_buff *skb), + void *from, int length, int transhdrlen, + struct ipcm6_cookie *ipc6, struct flowi6 *fl6, + struct rt6_info *rt, unsigned int flags, + struct inet_cork_full *cork); + +static inline struct sk_buff *ip6_finish_skb(struct sock *sk) +{ + return __ip6_make_skb(sk, &sk->sk_write_queue, &inet_sk(sk)->cork, + &inet6_sk(sk)->cork); +} + +int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst, + struct flowi6 *fl6); +struct dst_entry *ip6_dst_lookup_flow(struct net *net, const struct sock *sk, struct flowi6 *fl6, + const struct in6_addr *final_dst); +struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6, + const struct in6_addr *final_dst, + bool connected); +struct dst_entry *ip6_dst_lookup_tunnel(struct sk_buff *skb, + struct net_device *dev, + struct net *net, struct socket *sock, + struct in6_addr *saddr, + const struct ip_tunnel_info *info, + u8 protocol, bool use_cache); +struct dst_entry *ip6_blackhole_route(struct net *net, + struct dst_entry *orig_dst); + +/* + * skb processing functions + */ + +int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb); +int ip6_forward(struct sk_buff *skb); +int ip6_input(struct sk_buff *skb); +int ip6_mc_input(struct sk_buff *skb); +void ip6_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int nexthdr, + bool have_final); + +int __ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); +int ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); + +/* + * Extension header (options) processing + */ + +void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, + u8 *proto, struct in6_addr **daddr_p, + struct in6_addr *saddr); +void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, + u8 *proto); + +int ipv6_skip_exthdr(const struct sk_buff *, int start, u8 *nexthdrp, + __be16 *frag_offp); + +bool ipv6_ext_hdr(u8 nexthdr); + +enum { + IP6_FH_F_FRAG = (1 << 0), + IP6_FH_F_AUTH = (1 << 1), + IP6_FH_F_SKIP_RH = (1 << 2), +}; + +/* find specified header and get offset to it */ +int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, int target, + unsigned short *fragoff, int *fragflg); + +int ipv6_find_tlv(const struct sk_buff *skb, int offset, int type); + +struct in6_addr *fl6_update_dst(struct flowi6 *fl6, + const struct ipv6_txoptions *opt, + struct in6_addr *orig); + +/* + * socket options (ipv6_sockglue.c) + */ + +int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, + unsigned int optlen); +int ipv6_getsockopt(struct sock *sk, int level, int optname, + char __user *optval, int __user *optlen); + +int __ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, + int addr_len); +int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len); +int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr, + int addr_len); +int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr); +void ip6_datagram_release_cb(struct sock *sk); + +int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, + int *addr_len); +int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len, + int *addr_len); +void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port, + u32 info, u8 *payload); +void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info); +void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu); + +void inet6_cleanup_sock(struct sock *sk); +void inet6_sock_destruct(struct sock *sk); +int inet6_release(struct socket *sock); +int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len); +int inet6_getname(struct socket *sock, struct sockaddr *uaddr, + int peer); +int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg); +int inet6_compat_ioctl(struct socket *sock, unsigned int cmd, + unsigned long arg); + +int inet6_hash_connect(struct inet_timewait_death_row *death_row, + struct sock *sk); +int inet6_sendmsg(struct socket *sock, struct msghdr *msg, size_t size); +int inet6_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, + int flags); + +/* + * reassembly.c + */ +extern const struct proto_ops inet6_stream_ops; +extern const struct proto_ops inet6_dgram_ops; +extern const struct proto_ops inet6_sockraw_ops; + +struct group_source_req; +struct group_filter; + +int ip6_mc_source(int add, int omode, struct sock *sk, + struct group_source_req *pgsr); +int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf, + struct sockaddr_storage *list); +int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf, + struct sockaddr_storage __user *p); + +#ifdef CONFIG_PROC_FS +int ac6_proc_init(struct net *net); +void ac6_proc_exit(struct net *net); +int raw6_proc_init(void); +void raw6_proc_exit(void); +int tcp6_proc_init(struct net *net); +void tcp6_proc_exit(struct net *net); +int udp6_proc_init(struct net *net); +void udp6_proc_exit(struct net *net); +int udplite6_proc_init(void); +void udplite6_proc_exit(void); +int ipv6_misc_proc_init(void); +void ipv6_misc_proc_exit(void); +int snmp6_register_dev(struct inet6_dev *idev); +int snmp6_unregister_dev(struct inet6_dev *idev); + +#else +static inline int ac6_proc_init(struct net *net) { return 0; } +static inline void ac6_proc_exit(struct net *net) { } +static inline int snmp6_register_dev(struct inet6_dev *idev) { return 0; } +static inline int snmp6_unregister_dev(struct inet6_dev *idev) { return 0; } +#endif + +#ifdef CONFIG_SYSCTL +struct ctl_table *ipv6_icmp_sysctl_init(struct net *net); +struct ctl_table *ipv6_route_sysctl_init(struct net *net); +int ipv6_sysctl_register(void); +void ipv6_sysctl_unregister(void); +#endif + +int ipv6_sock_mc_join(struct sock *sk, int ifindex, + const struct in6_addr *addr); +int ipv6_sock_mc_join_ssm(struct sock *sk, int ifindex, + const struct in6_addr *addr, unsigned int mode); +int ipv6_sock_mc_drop(struct sock *sk, int ifindex, + const struct in6_addr *addr); + +static inline int ip6_sock_set_v6only(struct sock *sk) +{ + if (inet_sk(sk)->inet_num) + return -EINVAL; + lock_sock(sk); + sk->sk_ipv6only = true; + release_sock(sk); + return 0; +} + +static inline void ip6_sock_set_recverr(struct sock *sk) +{ + lock_sock(sk); + inet6_sk(sk)->recverr = true; + release_sock(sk); +} + +static inline int __ip6_sock_set_addr_preferences(struct sock *sk, int val) +{ + unsigned int pref = 0; + unsigned int prefmask = ~0; + + /* check PUBLIC/TMP/PUBTMP_DEFAULT conflicts */ + switch (val & (IPV6_PREFER_SRC_PUBLIC | + IPV6_PREFER_SRC_TMP | + IPV6_PREFER_SRC_PUBTMP_DEFAULT)) { + case IPV6_PREFER_SRC_PUBLIC: + pref |= IPV6_PREFER_SRC_PUBLIC; + prefmask &= ~(IPV6_PREFER_SRC_PUBLIC | + IPV6_PREFER_SRC_TMP); + break; + case IPV6_PREFER_SRC_TMP: + pref |= IPV6_PREFER_SRC_TMP; + prefmask &= ~(IPV6_PREFER_SRC_PUBLIC | + IPV6_PREFER_SRC_TMP); + break; + case IPV6_PREFER_SRC_PUBTMP_DEFAULT: + prefmask &= ~(IPV6_PREFER_SRC_PUBLIC | + IPV6_PREFER_SRC_TMP); + break; + case 0: + break; + default: + return -EINVAL; + } + + /* check HOME/COA conflicts */ + switch (val & (IPV6_PREFER_SRC_HOME | IPV6_PREFER_SRC_COA)) { + case IPV6_PREFER_SRC_HOME: + prefmask &= ~IPV6_PREFER_SRC_COA; + break; + case IPV6_PREFER_SRC_COA: + pref |= IPV6_PREFER_SRC_COA; + break; + case 0: + break; + default: + return -EINVAL; + } + + /* check CGA/NONCGA conflicts */ + switch (val & (IPV6_PREFER_SRC_CGA|IPV6_PREFER_SRC_NONCGA)) { + case IPV6_PREFER_SRC_CGA: + case IPV6_PREFER_SRC_NONCGA: + case 0: + break; + default: + return -EINVAL; + } + + inet6_sk(sk)->srcprefs = (inet6_sk(sk)->srcprefs & prefmask) | pref; + return 0; +} + +static inline int ip6_sock_set_addr_preferences(struct sock *sk, int val) +{ + int ret; + + lock_sock(sk); + ret = __ip6_sock_set_addr_preferences(sk, val); + release_sock(sk); + return ret; +} + +static inline void ip6_sock_set_recvpktinfo(struct sock *sk) +{ + lock_sock(sk); + inet6_sk(sk)->rxopt.bits.rxinfo = true; + release_sock(sk); +} + +#endif /* _NET_IPV6_H */ |