usr/src/sys/netinet/in_pcb.c

/*	in_pcb.c	4.21	82/03/23	*/

#include "../h/param.h"
#include "../h/systm.h"
#include "../h/dir.h"
#include "../h/user.h"
#include "../h/mbuf.h"
#include "../h/socket.h"
#include "../h/socketvar.h"
#include "../net/in.h"
#include "../net/in_systm.h"
#include "../net/if.h"
#include "../net/in_pcb.h"
#include "../h/protosw.h"

/*
 * Routines to manage internet protocol control blocks.
 *
 * At PRU_ATTACH time a protocol control block is allocated in
 * in_pcballoc() and inserted on a doubly-linked list of such blocks
 * for the protocol.  A port address is either requested (and verified
 * to not be in use) or assigned at this time.  We also allocate
 * space in the socket sockbuf structures here, although this is
 * not a clearly correct place to put this function.
 *
 * A connectionless protocol will have its protocol control block
 * removed at PRU_DETACH time, when the socket will be freed (freeing
 * the space reserved) and the block will be removed from the list of
 * blocks for its protocol.
 *
 * A connection-based protocol may be connected to a remote peer at
 * PRU_CONNECT time through the routine in_pcbconnect().  In the normal
 * case a PRU_DISCONNECT occurs causing a in_pcbdisconnect().
 * It is also possible that higher-level routines will opt out of the
 * relationship with the connection before the connection shut down
 * is complete.  This often occurs in protocols like TCP where we must
 * hold on to the protocol control block for a unreasonably long time
 * after the connection is used up to avoid races in later connection
 * establishment.  To handle this we allow higher-level routines to
 * disassociate themselves from the socket, marking it SS_USERGONE while
 * the disconnect is in progress.  We notice that this has happened
 * when the disconnect is complete, and perform the PRU_DETACH operation,
 * freeing the socket.
 *
 * TODO:
 *	use hashing
 */
struct	in_addr zeroin_addr;

/*
 * Allocate a protocol control block, space
 * for send and receive data, and local host information.
 * Return error.  If no error make socket point at pcb.
 */
in_pcbattach(so, head, sndcc, rcvcc, sin)
	struct socket *so;
	struct inpcb *head;
	int sndcc, rcvcc;
	struct sockaddr_in *sin;
{
	struct mbuf *m;
	register struct inpcb *inp;
	u_short lport = 0;

COUNT(IN_PCBATTACH);
	if (ifnet == 0)
		return (EADDRNOTAVAIL);
	if (sin) {
		if (sin->sin_family != AF_INET)
			return (EAFNOSUPPORT);
		if (sin->sin_addr.s_addr &&
		    if_ifwithaddr(sin->sin_addr) == 0)
			return (EADDRNOTAVAIL);
		lport = sin->sin_port;
		if (lport) {
			u_short aport = lport;
			int wild = 0;
#if vax
			aport = htons(aport);
#endif
			/* GROSS */
			if (aport < IPPORT_RESERVED && u.u_uid != 0)
				return (EPERM);
			if ((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0 ||
			    (so->so_options & SO_ACCEPTCONN) == 0)
				wild = INPLOOKUP_WILDCARD;
			if (in_pcblookup(head,
			    zeroin_addr, 0, sin->sin_addr, lport, wild))
				return (EADDRINUSE);
		}
	}
	m = m_getclr(M_DONTWAIT);
	if (m == 0)
		return (ENOBUFS);
	if (sbreserve(&so->so_snd, sndcc) == 0)
		goto bad;
	if (sbreserve(&so->so_rcv, rcvcc) == 0)
		goto bad2;
	inp = mtod(m, struct inpcb *);
	inp->inp_head = head;
	if (sin)
		inp->inp_laddr = sin->sin_addr;
	if (lport == 0)
		do {
			if (head->inp_lport++ < IPPORT_RESERVED)
				head->inp_lport = IPPORT_RESERVED;
			lport = htons(head->inp_lport);
		} while (in_pcblookup(head,
			    zeroin_addr, 0, inp->inp_laddr, lport, 0));
	inp->inp_lport = lport;
	inp->inp_socket = so;
	insque(inp, head);
	so->so_pcb = (caddr_t)inp;
	in_setsockaddr(inp);
	return (0);
bad2:
	sbrelease(&so->so_snd);
bad:
	(void) m_free(m);
	return (ENOBUFS);
}

/*
 * Connect from a socket to a specified address.
 * Both address and port must be specified in argument sin.
 * If don't have a local address for this socket yet,
 * then pick one.
 */
in_pcbconnect(inp, sin)
	struct inpcb *inp;
	struct sockaddr_in *sin;
{
	struct ifnet *ifp;

COUNT(IN_PCBCONNECT);
	if (sin->sin_family != AF_INET)
		return (EAFNOSUPPORT);
	if (sin->sin_addr.s_addr == 0 || sin->sin_port == 0)
		return (EADDRNOTAVAIL);
	if (inp->inp_laddr.s_addr == 0) {
		ifp = if_ifonnetof(sin->sin_addr);
		if (ifp == 0)
			ifp = ifnet;
	}
	if (in_pcblookup(inp->inp_head,
	    sin->sin_addr,
	    sin->sin_port,
	    inp->inp_laddr.s_addr ? inp->inp_laddr : ifp->if_addr,
	    inp->inp_lport,
	    0))
		return (EADDRINUSE);
	if (inp->inp_laddr.s_addr == 0) {
		struct sockaddr_in *sin2 =
		    (struct sockaddr_in *)&inp->inp_socket->so_addr;

		inp->inp_laddr = ifp->if_addr;
		sin2->sin_addr = inp->inp_laddr;
	}
	inp->inp_faddr = sin->sin_addr;
	inp->inp_fport = sin->sin_port;
	return (0);
}

in_setsockaddr(inp)
	struct inpcb *inp;
{
	register struct sockaddr_in *sin =
	    (struct sockaddr_in *)&inp->inp_socket->so_addr;

	sin->sin_family = AF_INET;
	sin->sin_addr = inp->inp_laddr;
	sin->sin_port = inp->inp_lport;
}

in_pcbdisconnect(inp)
	struct inpcb *inp;
{

COUNT(IN_PCBDISCONNECT);
	inp->inp_faddr.s_addr = 0;
	inp->inp_fport = 0;
	if (inp->inp_socket->so_state & SS_USERGONE)
		in_pcbdetach(inp);
}

in_pcbdetach(inp)
	struct inpcb *inp;
{
	struct socket *so = inp->inp_socket;

	so->so_pcb = 0;
	sofree(so);
	remque(inp);
	(void) m_free(dtom(inp));
}

/*
 * SHOULD ALLOW MATCH ON MULTI-HOMING ONLY
 */
struct inpcb *
in_pcblookup(head, faddr, fport, laddr, lport, flags)
	struct inpcb *head;
	struct in_addr faddr, laddr;
	u_short fport, lport;
	int flags;
{
	register struct inpcb *inp, *match = 0;
	int matchwild = 3, wildcard;

	for (inp = head->inp_next; inp != head; inp = inp->inp_next) {
		if (inp->inp_lport != lport)
			continue;
		wildcard = 0;
		if (inp->inp_laddr.s_addr != 0) {
			if (laddr.s_addr == 0)
				wildcard++;
			else if (inp->inp_laddr.s_addr != laddr.s_addr)
				continue;
		} else {
			if (laddr.s_addr != 0)
				wildcard++;
		}
		if (inp->inp_faddr.s_addr != 0) {
			if (faddr.s_addr == 0)
				wildcard++;
			else if (inp->inp_faddr.s_addr != faddr.s_addr ||
			    inp->inp_fport != fport)
				continue;
		} else {
			if (faddr.s_addr != 0)
				wildcard++;
		}
		if (wildcard && (flags & INPLOOKUP_WILDCARD) == 0)
			continue;
		if (wildcard < matchwild) {
			match = inp;
			matchwild = wildcard;
			if (matchwild == 0)
				break;
		}
	}
	return (match);
}
Commit	Line	Data
	1	/* in_pcb.c 4.21 82/03/23 */
	2
	3	#include "../h/param.h"
	4	#include "../h/systm.h"
	5	#include "../h/dir.h"
	6	#include "../h/user.h"
	7	#include "../h/mbuf.h"
	8	#include "../h/socket.h"
	9	#include "../h/socketvar.h"
	10	#include "../net/in.h"
	11	#include "../net/in_systm.h"
	12	#include "../net/if.h"
	13	#include "../net/in_pcb.h"
	14	#include "../h/protosw.h"
	15
	16	/*
	17	* Routines to manage internet protocol control blocks.
	18	*
	19	* At PRU_ATTACH time a protocol control block is allocated in
	20	* in_pcballoc() and inserted on a doubly-linked list of such blocks
	21	* for the protocol. A port address is either requested (and verified
	22	* to not be in use) or assigned at this time. We also allocate
	23	* space in the socket sockbuf structures here, although this is
	24	* not a clearly correct place to put this function.
	25	*
	26	* A connectionless protocol will have its protocol control block
	27	* removed at PRU_DETACH time, when the socket will be freed (freeing
	28	* the space reserved) and the block will be removed from the list of
	29	* blocks for its protocol.
	30	*
	31	* A connection-based protocol may be connected to a remote peer at
	32	* PRU_CONNECT time through the routine in_pcbconnect(). In the normal
	33	* case a PRU_DISCONNECT occurs causing a in_pcbdisconnect().
	34	* It is also possible that higher-level routines will opt out of the
	35	* relationship with the connection before the connection shut down
	36	* is complete. This often occurs in protocols like TCP where we must
	37	* hold on to the protocol control block for a unreasonably long time
	38	* after the connection is used up to avoid races in later connection
	39	* establishment. To handle this we allow higher-level routines to
	40	* disassociate themselves from the socket, marking it SS_USERGONE while
	41	* the disconnect is in progress. We notice that this has happened
	42	* when the disconnect is complete, and perform the PRU_DETACH operation,
	43	* freeing the socket.
	44	*
	45	* TODO:
	46	* use hashing
	47	*/
	48	struct in_addr zeroin_addr;
	49
	50	/*
	51	* Allocate a protocol control block, space
	52	* for send and receive data, and local host information.
	53	* Return error. If no error make socket point at pcb.
	54	*/
	55	in_pcbattach(so, head, sndcc, rcvcc, sin)
	56	struct socket *so;
	57	struct inpcb *head;
	58	int sndcc, rcvcc;
	59	struct sockaddr_in *sin;
	60	{
	61	struct mbuf *m;
	62	register struct inpcb *inp;
	63	u_short lport = 0;
	64
	65	COUNT(IN_PCBATTACH);
	66	if (ifnet == 0)
	67	return (EADDRNOTAVAIL);
	68	if (sin) {
	69	if (sin->sin_family != AF_INET)
	70	return (EAFNOSUPPORT);
	71	if (sin->sin_addr.s_addr &&
	72	if_ifwithaddr(sin->sin_addr) == 0)
	73	return (EADDRNOTAVAIL);
	74	lport = sin->sin_port;
	75	if (lport) {
	76	u_short aport = lport;
	77	int wild = 0;
	78	#if vax
	79	aport = htons(aport);
	80	#endif
	81	/* GROSS */
	82	if (aport < IPPORT_RESERVED && u.u_uid != 0)
	83	return (EPERM);
	84	if ((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0 \|\|
	85	(so->so_options & SO_ACCEPTCONN) == 0)
	86	wild = INPLOOKUP_WILDCARD;
	87	if (in_pcblookup(head,
	88	zeroin_addr, 0, sin->sin_addr, lport, wild))
	89	return (EADDRINUSE);
	90	}
	91	}
	92	m = m_getclr(M_DONTWAIT);
	93	if (m == 0)
	94	return (ENOBUFS);
	95	if (sbreserve(&so->so_snd, sndcc) == 0)
	96	goto bad;
	97	if (sbreserve(&so->so_rcv, rcvcc) == 0)
	98	goto bad2;
	99	inp = mtod(m, struct inpcb *);
	100	inp->inp_head = head;
	101	if (sin)
	102	inp->inp_laddr = sin->sin_addr;
	103	if (lport == 0)
	104	do {
	105	if (head->inp_lport++ < IPPORT_RESERVED)
	106	head->inp_lport = IPPORT_RESERVED;
	107	lport = htons(head->inp_lport);
	108	} while (in_pcblookup(head,
	109	zeroin_addr, 0, inp->inp_laddr, lport, 0));
	110	inp->inp_lport = lport;
	111	inp->inp_socket = so;
	112	insque(inp, head);
	113	so->so_pcb = (caddr_t)inp;
	114	in_setsockaddr(inp);
	115	return (0);
	116	bad2:
	117	sbrelease(&so->so_snd);
	118	bad:
	119	(void) m_free(m);
	120	return (ENOBUFS);
	121	}
	122
	123	/*
	124	* Connect from a socket to a specified address.
	125	* Both address and port must be specified in argument sin.
	126	* If don't have a local address for this socket yet,
	127	* then pick one.
	128	*/
	129	in_pcbconnect(inp, sin)
	130	struct inpcb *inp;
	131	struct sockaddr_in *sin;
	132	{
	133	struct ifnet *ifp;
	134
	135	COUNT(IN_PCBCONNECT);
	136	if (sin->sin_family != AF_INET)
	137	return (EAFNOSUPPORT);
	138	if (sin->sin_addr.s_addr == 0 \|\| sin->sin_port == 0)
	139	return (EADDRNOTAVAIL);
	140	if (inp->inp_laddr.s_addr == 0) {
	141	ifp = if_ifonnetof(sin->sin_addr);
	142	if (ifp == 0)
	143	ifp = ifnet;
	144	}
	145	if (in_pcblookup(inp->inp_head,
	146	sin->sin_addr,
	147	sin->sin_port,
	148	inp->inp_laddr.s_addr ? inp->inp_laddr : ifp->if_addr,
	149	inp->inp_lport,
	150	0))
	151	return (EADDRINUSE);
	152	if (inp->inp_laddr.s_addr == 0) {
	153	struct sockaddr_in *sin2 =
	154	(struct sockaddr_in *)&inp->inp_socket->so_addr;
	155
	156	inp->inp_laddr = ifp->if_addr;
	157	sin2->sin_addr = inp->inp_laddr;
	158	}
	159	inp->inp_faddr = sin->sin_addr;
	160	inp->inp_fport = sin->sin_port;
	161	return (0);
	162	}
	163
	164	in_setsockaddr(inp)
	165	struct inpcb *inp;
	166	{
	167	register struct sockaddr_in *sin =
	168	(struct sockaddr_in *)&inp->inp_socket->so_addr;
	169
	170	sin->sin_family = AF_INET;
	171	sin->sin_addr = inp->inp_laddr;
	172	sin->sin_port = inp->inp_lport;
	173	}
	174
	175	in_pcbdisconnect(inp)
	176	struct inpcb *inp;
	177	{
	178
	179	COUNT(IN_PCBDISCONNECT);
	180	inp->inp_faddr.s_addr = 0;
	181	inp->inp_fport = 0;
	182	if (inp->inp_socket->so_state & SS_USERGONE)
	183	in_pcbdetach(inp);
	184	}
	185
	186	in_pcbdetach(inp)
	187	struct inpcb *inp;
	188	{
	189	struct socket *so = inp->inp_socket;
	190
	191	so->so_pcb = 0;
	192	sofree(so);
	193	remque(inp);
	194	(void) m_free(dtom(inp));
	195	}
	196
	197	/*
	198	* SHOULD ALLOW MATCH ON MULTI-HOMING ONLY
	199	*/
	200	struct inpcb *
	201	in_pcblookup(head, faddr, fport, laddr, lport, flags)
	202	struct inpcb *head;
	203	struct in_addr faddr, laddr;
	204	u_short fport, lport;
	205	int flags;
	206	{
	207	register struct inpcb inp, match = 0;
	208	int matchwild = 3, wildcard;
	209
	210	for (inp = head->inp_next; inp != head; inp = inp->inp_next) {
	211	if (inp->inp_lport != lport)
	212	continue;
	213	wildcard = 0;
	214	if (inp->inp_laddr.s_addr != 0) {
	215	if (laddr.s_addr == 0)
	216	wildcard++;
	217	else if (inp->inp_laddr.s_addr != laddr.s_addr)
	218	continue;
	219	} else {
	220	if (laddr.s_addr != 0)
	221	wildcard++;
	222	}
	223	if (inp->inp_faddr.s_addr != 0) {
	224	if (faddr.s_addr == 0)
	225	wildcard++;
	226	else if (inp->inp_faddr.s_addr != faddr.s_addr \|\|
	227	inp->inp_fport != fport)
	228	continue;
	229	} else {
	230	if (faddr.s_addr != 0)
	231	wildcard++;
	232	}
	233	if (wildcard && (flags & INPLOOKUP_WILDCARD) == 0)
	234	continue;
	235	if (wildcard < matchwild) {
	236	match = inp;
	237	matchwild = wildcard;
	238	if (matchwild == 0)
	239	break;
	240	}
	241	}
	242	return (match);
	243	}