freebsd-dev/sys/rpc/inet_pton.c

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Add the new kernel-mode NFS Lock Manager. To use it instead of the user-mode lock manager, build a kernel with the NFSLOCKD option and add '-k' to 'rpc_lockd_flags' in rc.conf. Highlights include: * Thread-safe kernel RPC client - many threads can use the same RPC client handle safely with replies being de-multiplexed at the socket upcall (typically driven directly by the NIC interrupt) and handed off to whichever thread matches the reply. For UDP sockets, many RPC clients can share the same socket. This allows the use of a single privileged UDP port number to talk to an arbitrary number of remote hosts. * Single-threaded kernel RPC server. Adding support for multi-threaded server would be relatively straightforward and would follow approximately the Solaris KPI. A single thread should be sufficient for the NLM since it should rarely block in normal operation. * Kernel mode NLM server supporting cancel requests and granted callbacks. I've tested the NLM server reasonably extensively - it passes both my own tests and the NFS Connectathon locking tests running on Solaris, Mac OS X and Ubuntu Linux. * Userland NLM client supported. While the NLM server doesn't have support for the local NFS client's locking needs, it does have to field async replies and granted callbacks from remote NLMs that the local client has contacted. We relay these replies to the userland rpc.lockd over a local domain RPC socket. * Robust deadlock detection for the local lock manager. In particular it will detect deadlocks caused by a lock request that covers more than one blocking request. As required by the NLM protocol, all deadlock detection happens synchronously - a user is guaranteed that if a lock request isn't rejected immediately, the lock will eventually be granted. The old system allowed for a 'deferred deadlock' condition where a blocked lock request could wake up and find that some other deadlock-causing lock owner had beaten them to the lock. * Since both local and remote locks are managed by the same kernel locking code, local and remote processes can safely use file locks for mutual exclusion. Local processes have no fairness advantage compared to remote processes when contending to lock a region that has just been unlocked - the local lock manager enforces a strict first-come first-served model for both local and remote lockers. Sponsored by: Isilon Systems PR: 95247 107555 115524 116679 MFC after: 2 weeks
2008-03-26 15:23:12 +00:00
/*
* Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
* Copyright (c) 1996,1999 by Internet Software Consortium.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
* OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static const char rcsid[] = "$Id: inet_pton.c,v 1.3.18.2 2005/07/28 07:38:07 marka Exp $";
#endif /* LIBC_SCCS and not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/systm.h>
#include <rpc/types.h>
#include <rpc/rpc_com.h>
#if __FreeBSD_version < 700000
#define strchr index
#endif
Add the new kernel-mode NFS Lock Manager. To use it instead of the user-mode lock manager, build a kernel with the NFSLOCKD option and add '-k' to 'rpc_lockd_flags' in rc.conf. Highlights include: * Thread-safe kernel RPC client - many threads can use the same RPC client handle safely with replies being de-multiplexed at the socket upcall (typically driven directly by the NIC interrupt) and handed off to whichever thread matches the reply. For UDP sockets, many RPC clients can share the same socket. This allows the use of a single privileged UDP port number to talk to an arbitrary number of remote hosts. * Single-threaded kernel RPC server. Adding support for multi-threaded server would be relatively straightforward and would follow approximately the Solaris KPI. A single thread should be sufficient for the NLM since it should rarely block in normal operation. * Kernel mode NLM server supporting cancel requests and granted callbacks. I've tested the NLM server reasonably extensively - it passes both my own tests and the NFS Connectathon locking tests running on Solaris, Mac OS X and Ubuntu Linux. * Userland NLM client supported. While the NLM server doesn't have support for the local NFS client's locking needs, it does have to field async replies and granted callbacks from remote NLMs that the local client has contacted. We relay these replies to the userland rpc.lockd over a local domain RPC socket. * Robust deadlock detection for the local lock manager. In particular it will detect deadlocks caused by a lock request that covers more than one blocking request. As required by the NLM protocol, all deadlock detection happens synchronously - a user is guaranteed that if a lock request isn't rejected immediately, the lock will eventually be granted. The old system allowed for a 'deferred deadlock' condition where a blocked lock request could wake up and find that some other deadlock-causing lock owner had beaten them to the lock. * Since both local and remote locks are managed by the same kernel locking code, local and remote processes can safely use file locks for mutual exclusion. Local processes have no fairness advantage compared to remote processes when contending to lock a region that has just been unlocked - the local lock manager enforces a strict first-come first-served model for both local and remote lockers. Sponsored by: Isilon Systems PR: 95247 107555 115524 116679 MFC after: 2 weeks
2008-03-26 15:23:12 +00:00
/*%
* WARNING: Don't even consider trying to compile this on a system where
* sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX.
*/
static int inet_pton4(const char *src, u_char *dst);
static int inet_pton6(const char *src, u_char *dst);
/* int
* inet_pton(af, src, dst)
* convert from presentation format (which usually means ASCII printable)
* to network format (which is usually some kind of binary format).
* return:
* 1 if the address was valid for the specified address family
* 0 if the address wasn't valid (`dst' is untouched in this case)
* -1 if some other error occurred (`dst' is untouched in this case, too)
* author:
* Paul Vixie, 1996.
*/
int
__rpc_inet_pton(int af, const char * __restrict src, void * __restrict dst)
{
switch (af) {
case AF_INET:
return (inet_pton4(src, dst));
case AF_INET6:
return (inet_pton6(src, dst));
default:
return (-1);
}
/* NOTREACHED */
}
/* int
* inet_pton4(src, dst)
* like inet_aton() but without all the hexadecimal and shorthand.
* return:
* 1 if `src' is a valid dotted quad, else 0.
* notice:
* does not touch `dst' unless it's returning 1.
* author:
* Paul Vixie, 1996.
*/
static int
inet_pton4(const char *src, u_char *dst)
{
static const char digits[] = "0123456789";
int saw_digit, octets, ch;
#define NS_INADDRSZ 4
u_char tmp[NS_INADDRSZ], *tp;
saw_digit = 0;
octets = 0;
*(tp = tmp) = 0;
while ((ch = *src++) != '\0') {
const char *pch;
if ((pch = strchr(digits, ch)) != NULL) {
u_int new = *tp * 10 + (pch - digits);
if (saw_digit && *tp == 0)
return (0);
if (new > 255)
return (0);
*tp = new;
if (!saw_digit) {
if (++octets > 4)
return (0);
saw_digit = 1;
}
} else if (ch == '.' && saw_digit) {
if (octets == 4)
return (0);
*++tp = 0;
saw_digit = 0;
} else
return (0);
}
if (octets < 4)
return (0);
memcpy(dst, tmp, NS_INADDRSZ);
return (1);
}
/* int
* inet_pton6(src, dst)
* convert presentation level address to network order binary form.
* return:
* 1 if `src' is a valid [RFC1884 2.2] address, else 0.
* notice:
* (1) does not touch `dst' unless it's returning 1.
* (2) :: in a full address is silently ignored.
* credit:
* inspired by Mark Andrews.
* author:
* Paul Vixie, 1996.
*/
static int
inet_pton6(const char *src, u_char *dst)
{
static const char xdigits_l[] = "0123456789abcdef",
xdigits_u[] = "0123456789ABCDEF";
#define NS_IN6ADDRSZ 16
#define NS_INT16SZ 2
u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
const char *xdigits, *curtok;
int ch, seen_xdigits;
u_int val;
memset((tp = tmp), '\0', NS_IN6ADDRSZ);
endp = tp + NS_IN6ADDRSZ;
colonp = NULL;
/* Leading :: requires some special handling. */
if (*src == ':')
if (*++src != ':')
return (0);
curtok = src;
seen_xdigits = 0;
val = 0;
while ((ch = *src++) != '\0') {
const char *pch;
if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
pch = strchr((xdigits = xdigits_u), ch);
if (pch != NULL) {
val <<= 4;
val |= (pch - xdigits);
if (++seen_xdigits > 4)
return (0);
continue;
}
if (ch == ':') {
curtok = src;
if (!seen_xdigits) {
if (colonp)
return (0);
colonp = tp;
continue;
} else if (*src == '\0') {
return (0);
}
if (tp + NS_INT16SZ > endp)
return (0);
*tp++ = (u_char) (val >> 8) & 0xff;
*tp++ = (u_char) val & 0xff;
seen_xdigits = 0;
val = 0;
continue;
}
if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
inet_pton4(curtok, tp) > 0) {
tp += NS_INADDRSZ;
seen_xdigits = 0;
break; /*%< '\\0' was seen by inet_pton4(). */
}
return (0);
}
if (seen_xdigits) {
if (tp + NS_INT16SZ > endp)
return (0);
*tp++ = (u_char) (val >> 8) & 0xff;
*tp++ = (u_char) val & 0xff;
}
if (colonp != NULL) {
/*
* Since some memmove()'s erroneously fail to handle
* overlapping regions, we'll do the shift by hand.
*/
const int n = tp - colonp;
int i;
if (tp == endp)
return (0);
for (i = 1; i <= n; i++) {
endp[- i] = colonp[n - i];
colonp[n - i] = 0;
}
tp = endp;
}
if (tp != endp)
return (0);
memcpy(dst, tmp, NS_IN6ADDRSZ);
return (1);
}
/*
* Weak aliases for applications that use certain private entry points,
* and fail to include <arpa/inet.h>.
*/
#undef inet_pton
__weak_reference(__inet_pton, inet_pton);
/*! \file */