freebsd-skq/sys/netinet/in_pcb.h
Adrian Chadd be9347e3fe Implement a new IP option (not compiled/enabled by default) to allow
applications to specify a non-local IP address when bind()'ing a socket
to a local endpoint.

This allows applications to spoof the client IP address of connections
if (obviously!) they somehow are able to receive the traffic normally
destined to said clients.

This patch doesn't include any changes to ipfw or the bridging code to
redirect the client traffic through the PCB checks so TCP gets a shot
at it. The normal behaviour is that packets with a non-local destination
IP address are not handled locally. This can be dealth with some IPFW hackery;
modifications to IPFW to make this less hacky will occur in subsequent
commmits.

Thanks to Julian Elischer and others at Ironport. This work was approved
and donated before Cisco acquired them.

Obtained from:	Julian Elischer and others
MFC after:	2 weeks
2009-01-09 16:02:19 +00:00

520 lines
18 KiB
C

/*-
* Copyright (c) 1982, 1986, 1990, 1993
* The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)in_pcb.h 8.1 (Berkeley) 6/10/93
* $FreeBSD$
*/
#ifndef _NETINET_IN_PCB_H_
#define _NETINET_IN_PCB_H_
#include <sys/queue.h>
#include <sys/_lock.h>
#include <sys/_mutex.h>
#include <sys/_rwlock.h>
#include <net/route.h>
#ifdef _KERNEL
#include <sys/rwlock.h>
#endif
#define in6pcb inpcb /* for KAME src sync over BSD*'s */
#define in6p_sp inp_sp /* for KAME src sync over BSD*'s */
struct inpcbpolicy;
/*
* struct inpcb is the common protocol control block structure used in most
* IP transport protocols.
*
* Pointers to local and foreign host table entries, local and foreign socket
* numbers, and pointers up (to a socket structure) and down (to a
* protocol-specific control block) are stored here.
*/
LIST_HEAD(inpcbhead, inpcb);
LIST_HEAD(inpcbporthead, inpcbport);
typedef u_quad_t inp_gen_t;
/*
* PCB with AF_INET6 null bind'ed laddr can receive AF_INET input packet.
* So, AF_INET6 null laddr is also used as AF_INET null laddr, by utilizing
* the following structure.
*/
struct in_addr_4in6 {
u_int32_t ia46_pad32[3];
struct in_addr ia46_addr4;
};
/*
* NOTE: ipv6 addrs should be 64-bit aligned, per RFC 2553. in_conninfo has
* some extra padding to accomplish this.
*/
struct in_endpoints {
u_int16_t ie_fport; /* foreign port */
u_int16_t ie_lport; /* local port */
/* protocol dependent part, local and foreign addr */
union {
/* foreign host table entry */
struct in_addr_4in6 ie46_foreign;
struct in6_addr ie6_foreign;
} ie_dependfaddr;
union {
/* local host table entry */
struct in_addr_4in6 ie46_local;
struct in6_addr ie6_local;
} ie_dependladdr;
};
#define ie_faddr ie_dependfaddr.ie46_foreign.ia46_addr4
#define ie_laddr ie_dependladdr.ie46_local.ia46_addr4
#define ie6_faddr ie_dependfaddr.ie6_foreign
#define ie6_laddr ie_dependladdr.ie6_local
/*
* XXX The defines for inc_* are hacks and should be changed to direct
* references.
*/
struct in_conninfo {
u_int8_t inc_flags;
u_int8_t inc_len;
u_int16_t inc_fibnum; /* XXX was pad, 16 bits is plenty */
/* protocol dependent part */
struct in_endpoints inc_ie;
};
/*
* Flags for inc_flags.
*/
#define INC_ISIPV6 0x01
#define inc_isipv6 inc_flags /* temp compatability */
#define inc_fport inc_ie.ie_fport
#define inc_lport inc_ie.ie_lport
#define inc_faddr inc_ie.ie_faddr
#define inc_laddr inc_ie.ie_laddr
#define inc6_faddr inc_ie.ie6_faddr
#define inc6_laddr inc_ie.ie6_laddr
struct icmp6_filter;
/*-
* struct inpcb captures the network layer state for TCP, UDP, and raw IPv4
* and IPv6 sockets. In the case of TCP, further per-connection state is
* hung off of inp_ppcb most of the time. Almost all fields of struct inpcb
* are static after creation or protected by a per-inpcb rwlock, inp_lock. A
* few fields also require the global pcbinfo lock for the inpcb to be held,
* when modified, such as the global connection lists and hashes, as well as
* binding information (which affects which hash a connection is on). This
* model means that connections can be looked up without holding the
* per-connection lock, which is important for performance when attempting to
* find the connection for a packet given its IP and port tuple. Writing to
* these fields that write locks be held on both the inpcb and global locks.
*
* Key:
* (c) - Constant after initialization
* (i) - Protected by the inpcb lock
* (p) - Protected by the pcbinfo lock for the inpcb
* (s) - Protected by another subsystem's locks
* (x) - Undefined locking
*
* A few other notes:
*
* When a read lock is held, stability of the field is guaranteed; to write
* to a field, a write lock must generally be held.
*
* netinet/netinet6-layer code should not assume that the inp_socket pointer
* is safe to dereference without inp_lock being held, even for protocols
* other than TCP (where the inpcb persists during TIMEWAIT even after the
* socket has been freed), or there may be close(2)-related races.
*
* The inp_vflag field is overloaded, and would otherwise ideally be (c).
*/
struct inpcb {
LIST_ENTRY(inpcb) inp_hash; /* (i/p) hash list */
LIST_ENTRY(inpcb) inp_list; /* (i/p) list for all PCBs for proto */
void *inp_ppcb; /* (i) pointer to per-protocol pcb */
struct inpcbinfo *inp_pcbinfo; /* (c) PCB list info */
struct socket *inp_socket; /* (i) back pointer to socket */
struct ucred *inp_cred; /* (c) cache of socket cred */
u_int32_t inp_flow; /* (i) IPv6 flow information */
int inp_flags; /* (i) generic IP/datagram flags */
u_char inp_vflag; /* (i) IP version flag (v4/v6) */
u_char inp_ip_ttl; /* (i) time to live proto */
u_char inp_ip_p; /* (c) protocol proto */
u_char inp_ip_minttl; /* (i) minimum TTL or drop */
uint32_t inp_ispare1; /* (x) connection id / queue id */
u_int inp_refcount; /* (i) refcount */
void *inp_pspare[2]; /* (x) rtentry / general use */
/* Local and foreign ports, local and foreign addr. */
struct in_conninfo inp_inc; /* (i/p) list for PCB's local port */
/* MAC and IPSEC policy information. */
struct label *inp_label; /* (i) MAC label */
struct inpcbpolicy *inp_sp; /* (s) for IPSEC */
/* Protocol-dependent part; options. */
struct {
u_char inp4_ip_tos; /* (i) type of service proto */
struct mbuf *inp4_options; /* (i) IP options */
struct ip_moptions *inp4_moptions; /* (i) IP mcast options */
} inp_depend4;
struct {
/* (i) IP options */
struct mbuf *inp6_options;
/* (i) IP6 options for outgoing packets */
struct ip6_pktopts *inp6_outputopts;
/* (i) IP multicast options */
struct ip6_moptions *inp6_moptions;
/* (i) ICMPv6 code type filter */
struct icmp6_filter *inp6_icmp6filt;
/* (i) IPV6_CHECKSUM setsockopt */
int inp6_cksum;
short inp6_hops;
} inp_depend6;
LIST_ENTRY(inpcb) inp_portlist; /* (i/p) */
struct inpcbport *inp_phd; /* (i/p) head of this list */
#define inp_zero_size offsetof(struct inpcb, inp_gencnt)
inp_gen_t inp_gencnt; /* (c) generation count */
struct rwlock inp_lock;
};
#define inp_fport inp_inc.inc_fport
#define inp_lport inp_inc.inc_lport
#define inp_faddr inp_inc.inc_faddr
#define inp_laddr inp_inc.inc_laddr
#define inp_ip_tos inp_depend4.inp4_ip_tos
#define inp_options inp_depend4.inp4_options
#define inp_moptions inp_depend4.inp4_moptions
#define in6p_faddr inp_inc.inc6_faddr
#define in6p_laddr inp_inc.inc6_laddr
#define in6p_hops inp_depend6.inp6_hops /* default hop limit */
#define in6p_ip6_nxt inp_ip_p
#define in6p_flowinfo inp_flow
#define in6p_vflag inp_vflag
#define in6p_options inp_depend6.inp6_options
#define in6p_outputopts inp_depend6.inp6_outputopts
#define in6p_moptions inp_depend6.inp6_moptions
#define in6p_icmp6filt inp_depend6.inp6_icmp6filt
#define in6p_cksum inp_depend6.inp6_cksum
#define in6p_flags inp_flags /* for KAME src sync over BSD*'s */
#define in6p_socket inp_socket /* for KAME src sync over BSD*'s */
#define in6p_lport inp_lport /* for KAME src sync over BSD*'s */
#define in6p_fport inp_fport /* for KAME src sync over BSD*'s */
#define in6p_ppcb inp_ppcb /* for KAME src sync over BSD*'s */
/*
* The range of the generation count, as used in this implementation, is 9e19.
* We would have to create 300 billion connections per second for this number
* to roll over in a year. This seems sufficiently unlikely that we simply
* don't concern ourselves with that possibility.
*/
/*
* Interface exported to userland by various protocols which use inpcbs. Hack
* alert -- only define if struct xsocket is in scope.
*/
#ifdef _SYS_SOCKETVAR_H_
struct xinpcb {
size_t xi_len; /* length of this structure */
struct inpcb xi_inp;
struct xsocket xi_socket;
u_quad_t xi_alignment_hack;
};
struct xinpgen {
size_t xig_len; /* length of this structure */
u_int xig_count; /* number of PCBs at this time */
inp_gen_t xig_gen; /* generation count at this time */
so_gen_t xig_sogen; /* socket generation count at this time */
};
#endif /* _SYS_SOCKETVAR_H_ */
struct inpcbport {
LIST_ENTRY(inpcbport) phd_hash;
struct inpcbhead phd_pcblist;
u_short phd_port;
};
/*
* Global data structure for each high-level protocol (UDP, TCP, ...) in both
* IPv4 and IPv6. Holds inpcb lists and information for managing them.
*/
struct inpcbinfo {
/*
* Global list of inpcbs on the protocol.
*/
struct inpcbhead *ipi_listhead;
u_int ipi_count;
/*
* Global hash of inpcbs, hashed by local and foreign addresses and
* port numbers.
*/
struct inpcbhead *ipi_hashbase;
u_long ipi_hashmask;
/*
* Global hash of inpcbs, hashed by only local port number.
*/
struct inpcbporthead *ipi_porthashbase;
u_long ipi_porthashmask;
/*
* Fields associated with port lookup and allocation.
*/
u_short ipi_lastport;
u_short ipi_lastlow;
u_short ipi_lasthi;
/*
* UMA zone from which inpcbs are allocated for this protocol.
*/
struct uma_zone *ipi_zone;
/*
* Generation count--incremented each time a connection is allocated
* or freed.
*/
u_quad_t ipi_gencnt;
struct rwlock ipi_lock;
/*
* vimage 1
* general use 1
*/
void *ipi_pspare[2];
};
#define INP_LOCK_INIT(inp, d, t) \
rw_init_flags(&(inp)->inp_lock, (t), RW_RECURSE | RW_DUPOK)
#define INP_LOCK_DESTROY(inp) rw_destroy(&(inp)->inp_lock)
#define INP_RLOCK(inp) rw_rlock(&(inp)->inp_lock)
#define INP_WLOCK(inp) rw_wlock(&(inp)->inp_lock)
#define INP_TRY_RLOCK(inp) rw_try_rlock(&(inp)->inp_lock)
#define INP_TRY_WLOCK(inp) rw_try_wlock(&(inp)->inp_lock)
#define INP_RUNLOCK(inp) rw_runlock(&(inp)->inp_lock)
#define INP_WUNLOCK(inp) rw_wunlock(&(inp)->inp_lock)
#define INP_LOCK_ASSERT(inp) rw_assert(&(inp)->inp_lock, RA_LOCKED)
#define INP_RLOCK_ASSERT(inp) rw_assert(&(inp)->inp_lock, RA_RLOCKED)
#define INP_WLOCK_ASSERT(inp) rw_assert(&(inp)->inp_lock, RA_WLOCKED)
#define INP_UNLOCK_ASSERT(inp) rw_assert(&(inp)->inp_lock, RA_UNLOCKED)
#ifdef _KERNEL
/*
* These locking functions are for inpcb consumers outside of sys/netinet,
* more specifically, they were added for the benefit of TOE drivers. The
* macros are reserved for use by the stack.
*/
void inp_wlock(struct inpcb *);
void inp_wunlock(struct inpcb *);
void inp_rlock(struct inpcb *);
void inp_runlock(struct inpcb *);
#ifdef INVARIANTS
void inp_lock_assert(struct inpcb *);
void inp_unlock_assert(struct inpcb *);
#else
static __inline void
inp_lock_assert(struct inpcb *inp __unused)
{
}
static __inline void
inp_unlock_assert(struct inpcb *inp __unused)
{
}
#endif
void inp_apply_all(void (*func)(struct inpcb *, void *), void *arg);
int inp_ip_tos_get(const struct inpcb *inp);
void inp_ip_tos_set(struct inpcb *inp, int val);
struct socket *
inp_inpcbtosocket(struct inpcb *inp);
struct tcpcb *
inp_inpcbtotcpcb(struct inpcb *inp);
void inp_4tuple_get(struct inpcb *inp, uint32_t *laddr, uint16_t *lp,
uint32_t *faddr, uint16_t *fp);
#endif /* _KERNEL */
#define INP_INFO_LOCK_INIT(ipi, d) \
rw_init_flags(&(ipi)->ipi_lock, (d), RW_RECURSE)
#define INP_INFO_LOCK_DESTROY(ipi) rw_destroy(&(ipi)->ipi_lock)
#define INP_INFO_RLOCK(ipi) rw_rlock(&(ipi)->ipi_lock)
#define INP_INFO_WLOCK(ipi) rw_wlock(&(ipi)->ipi_lock)
#define INP_INFO_TRY_RLOCK(ipi) rw_try_rlock(&(ipi)->ipi_lock)
#define INP_INFO_TRY_WLOCK(ipi) rw_try_wlock(&(ipi)->ipi_lock)
#define INP_INFO_RUNLOCK(ipi) rw_runlock(&(ipi)->ipi_lock)
#define INP_INFO_WUNLOCK(ipi) rw_wunlock(&(ipi)->ipi_lock)
#define INP_INFO_LOCK_ASSERT(ipi) rw_assert(&(ipi)->ipi_lock, RA_LOCKED)
#define INP_INFO_RLOCK_ASSERT(ipi) rw_assert(&(ipi)->ipi_lock, RA_RLOCKED)
#define INP_INFO_WLOCK_ASSERT(ipi) rw_assert(&(ipi)->ipi_lock, RA_WLOCKED)
#define INP_INFO_UNLOCK_ASSERT(ipi) rw_assert(&(ipi)->ipi_lock, RA_UNLOCKED)
#define INP_PCBHASH(faddr, lport, fport, mask) \
(((faddr) ^ ((faddr) >> 16) ^ ntohs((lport) ^ (fport))) & (mask))
#define INP_PCBPORTHASH(lport, mask) \
(ntohs((lport)) & (mask))
/*
* Flags for inp_vflags -- historically version flags only, but now quite a
* bit more due to an overflow of inp_flag, leading to some locking ambiguity
* as some bits are stable from initial allocation, and others may change.
*/
#define INP_IPV4 0x1
#define INP_IPV6 0x2
#define INP_IPV6PROTO 0x4 /* opened under IPv6 protocol */
#define INP_TIMEWAIT 0x8 /* inpcb in TIMEWAIT, ppcb is tcptw */
#define INP_ONESBCAST 0x10 /* send all-ones broadcast */
#define INP_DROPPED 0x20 /* protocol drop flag */
#define INP_SOCKREF 0x40 /* strong socket reference */
/*
* Flags for inp_flag.
*/
#define INP_RECVOPTS 0x01 /* receive incoming IP options */
#define INP_RECVRETOPTS 0x02 /* receive IP options for reply */
#define INP_RECVDSTADDR 0x04 /* receive IP dst address */
#define INP_HDRINCL 0x08 /* user supplies entire IP header */
#define INP_HIGHPORT 0x10 /* user wants "high" port binding */
#define INP_LOWPORT 0x20 /* user wants "low" port binding */
#define INP_ANONPORT 0x40 /* port chosen for user */
#define INP_RECVIF 0x80 /* receive incoming interface */
#define INP_MTUDISC 0x100 /* user can do MTU discovery */
#define INP_FAITH 0x200 /* accept FAITH'ed connections */
#define INP_RECVTTL 0x400 /* receive incoming IP TTL */
#define INP_DONTFRAG 0x800 /* don't fragment packet */
#define INP_NONLOCALOK 0x1000 /* Allow bind to spoof any address */
/* - requires options IP_NONLOCALBIND */
#define IN6P_IPV6_V6ONLY 0x008000 /* restrict AF_INET6 socket for v6 */
#define IN6P_PKTINFO 0x010000 /* receive IP6 dst and I/F */
#define IN6P_HOPLIMIT 0x020000 /* receive hoplimit */
#define IN6P_HOPOPTS 0x040000 /* receive hop-by-hop options */
#define IN6P_DSTOPTS 0x080000 /* receive dst options after rthdr */
#define IN6P_RTHDR 0x100000 /* receive routing header */
#define IN6P_RTHDRDSTOPTS 0x200000 /* receive dstoptions before rthdr */
#define IN6P_TCLASS 0x400000 /* receive traffic class value */
#define IN6P_AUTOFLOWLABEL 0x800000 /* attach flowlabel automatically */
#define IN6P_RFC2292 0x40000000 /* used RFC2292 API on the socket */
#define IN6P_MTU 0x80000000 /* receive path MTU */
#define INP_CONTROLOPTS (INP_RECVOPTS|INP_RECVRETOPTS|INP_RECVDSTADDR|\
INP_RECVIF|INP_RECVTTL|\
IN6P_PKTINFO|IN6P_HOPLIMIT|IN6P_HOPOPTS|\
IN6P_DSTOPTS|IN6P_RTHDR|IN6P_RTHDRDSTOPTS|\
IN6P_TCLASS|IN6P_AUTOFLOWLABEL|IN6P_RFC2292|\
IN6P_MTU)
#define INP_UNMAPPABLEOPTS (IN6P_HOPOPTS|IN6P_DSTOPTS|IN6P_RTHDR|\
IN6P_TCLASS|IN6P_AUTOFLOWLABEL)
/* for KAME src sync over BSD*'s */
#define IN6P_HIGHPORT INP_HIGHPORT
#define IN6P_LOWPORT INP_LOWPORT
#define IN6P_ANONPORT INP_ANONPORT
#define IN6P_RECVIF INP_RECVIF
#define IN6P_MTUDISC INP_MTUDISC
#define IN6P_FAITH INP_FAITH
#define IN6P_CONTROLOPTS INP_CONTROLOPTS
/*
* socket AF version is {newer than,or include}
* actual datagram AF version
*/
#define INPLOOKUP_WILDCARD 1
#define sotoinpcb(so) ((struct inpcb *)(so)->so_pcb)
#define sotoin6pcb(so) sotoinpcb(so) /* for KAME src sync over BSD*'s */
#define INP_SOCKAF(so) so->so_proto->pr_domain->dom_family
#define INP_CHECK_SOCKAF(so, af) (INP_SOCKAF(so) == af)
#ifdef _KERNEL
#ifdef VIMAGE_GLOBALS
extern int ipport_reservedhigh;
extern int ipport_reservedlow;
extern int ipport_lowfirstauto;
extern int ipport_lowlastauto;
extern int ipport_firstauto;
extern int ipport_lastauto;
extern int ipport_hifirstauto;
extern int ipport_hilastauto;
extern int ipport_randomized;
extern int ipport_randomcps;
extern int ipport_randomtime;
extern int ipport_stoprandom;
extern int ipport_tcpallocs;
#endif
extern struct callout ipport_tick_callout;
void in_pcbpurgeif0(struct inpcbinfo *, struct ifnet *);
int in_pcballoc(struct socket *, struct inpcbinfo *);
int in_pcbbind(struct inpcb *, struct sockaddr *, struct ucred *);
int in_pcbbind_setup(struct inpcb *, struct sockaddr *, in_addr_t *,
u_short *, struct ucred *);
int in_pcbconnect(struct inpcb *, struct sockaddr *, struct ucred *);
int in_pcbconnect_setup(struct inpcb *, struct sockaddr *, in_addr_t *,
u_short *, in_addr_t *, u_short *, struct inpcb **,
struct ucred *);
void in_pcbdetach(struct inpcb *);
void in_pcbdisconnect(struct inpcb *);
void in_pcbdrop(struct inpcb *);
void in_pcbfree(struct inpcb *);
int in_pcbinshash(struct inpcb *);
struct inpcb *
in_pcblookup_local(struct inpcbinfo *,
struct in_addr, u_short, int, struct ucred *);
struct inpcb *
in_pcblookup_hash(struct inpcbinfo *, struct in_addr, u_int,
struct in_addr, u_int, int, struct ifnet *);
void in_pcbnotifyall(struct inpcbinfo *pcbinfo, struct in_addr,
int, struct inpcb *(*)(struct inpcb *, int));
void in_pcbref(struct inpcb *);
void in_pcbrehash(struct inpcb *);
int in_pcbrele(struct inpcb *);
void in_pcbsetsolabel(struct socket *so);
int in_getpeeraddr(struct socket *so, struct sockaddr **nam);
int in_getsockaddr(struct socket *so, struct sockaddr **nam);
struct sockaddr *
in_sockaddr(in_port_t port, struct in_addr *addr);
void in_pcbsosetlabel(struct socket *so);
void in_pcbremlists(struct inpcb *inp);
void ipport_tick(void *xtp);
/*
* Debugging routines compiled in when DDB is present.
*/
void db_print_inpcb(struct inpcb *inp, const char *name, int indent);
#endif /* _KERNEL */
#endif /* !_NETINET_IN_PCB_H_ */