NetBSD/sys/netatalk/at_proto.c

109 lines
3.0 KiB
C
Raw Normal View History

/* $NetBSD: at_proto.c,v 1.16 2008/04/24 11:38:37 ad Exp $ */
/*
* Copyright (c) 1990,1991 Regents of The University of Michigan.
* All Rights Reserved.
*
* Permission to use, copy, modify, and distribute this software and
* its documentation for any purpose and without fee is hereby granted,
* provided that the above copyright notice appears in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation, and that the name of The University
* of Michigan not be used in advertising or publicity pertaining to
* distribution of the software without specific, written prior
* permission. This software is supplied as is without expressed or
* implied warranties of any kind.
*
* This product includes software developed by the University of
* California, Berkeley and its contributors.
*
* Research Systems Unix Group
* The University of Michigan
* c/o Wesley Craig
* 535 W. William Street
* Ann Arbor, Michigan
* +1-313-764-2278
* netatalk@umich.edu
*/
2001-11-13 03:00:58 +03:00
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: at_proto.c,v 1.16 2008/04/24 11:38:37 ad Exp $");
2001-11-13 03:00:58 +03:00
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/protosw.h>
#include <sys/domain.h>
#include <sys/socket.h>
#include <sys/kernel.h>
#include <net/if.h>
#include <net/radix.h>
#include <net/if_ether.h>
#include <netinet/in.h>
#include <net/route.h>
#include <netatalk/at.h>
#include <netatalk/ddp.h>
#include <netatalk/at_var.h>
#include <netatalk/ddp_var.h>
#include <netatalk/at_extern.h>
DOMAIN_DEFINE(atalkdomain); /* forward declare and add to link set */
PR_WRAP_USRREQ(ddp_usrreq)
#define ddp_usrreq ddp_usrreq_wrapper
const struct protosw atalksw[] = {
{
.pr_type = SOCK_DGRAM,
.pr_domain = &atalkdomain,
.pr_protocol = ATPROTO_DDP,
.pr_flags = PR_ATOMIC|PR_ADDR,
.pr_output = ddp_output,
.pr_usrreq = ddp_usrreq,
.pr_init = ddp_init,
},
};
struct domain atalkdomain = {
Here are various changes designed to protect against bad IPv4 routing caused by stale route caches (struct route). Route caches are sprinkled throughout PCBs, the IP fast-forwarding table, and IP tunnel interfaces (gre, gif, stf). Stale IPv6 and ISO route caches will be treated by separate patches. Thank you to Christoph Badura for suggesting the general approach to invalidating route caches that I take here. Here are the details: Add hooks to struct domain for tracking and for invalidating each domain's route caches: dom_rtcache, dom_rtflush, and dom_rtflushall. Introduce helper subroutines, rtflush(ro) for invalidating a route cache, rtflushall(family) for invalidating all route caches in a routing domain, and rtcache(ro) for notifying the domain of a new cached route. Chain together all IPv4 route caches where ro_rt != NULL. Provide in_rtcache() for adding a route to the chain. Provide in_rtflush() and in_rtflushall() for invalidating IPv4 route caches. In in_rtflush(), set ro_rt to NULL, and remove the route from the chain. In in_rtflushall(), walk the chain and remove every route cache. In rtrequest1(), call rtflushall() to invalidate route caches when a route is added. In gif(4), discard the workaround for stale caches that involves expiring them every so often. Replace the pattern 'RTFREE(ro->ro_rt); ro->ro_rt = NULL;' with a call to rtflush(ro). Update ipflow_fastforward() and all other users of route caches so that they expect a cached route, ro->ro_rt, to turn to NULL. Take care when moving a 'struct route' to rtflush() the source and to rtcache() the destination. In domain initializers, use .dom_xxx tags. KNF here and there.
2006-12-09 08:33:04 +03:00
.dom_family = PF_APPLETALK,
.dom_name = "appletalk",
.dom_init = NULL,
.dom_externalize = NULL,
.dom_dispose = NULL,
.dom_protosw = atalksw,
Eliminate address family-specific route caches (struct route, struct route_in6, struct route_iso), replacing all caches with a struct route. The principle benefit of this change is that all of the protocol families can benefit from route cache-invalidation, which is necessary for correct routing. Route-cache invalidation fixes an ancient PR, kern/3508, at long last; it fixes various other PRs, also. Discussions with and ideas from Joerg Sonnenberger influenced this work tremendously. Of course, all design oversights and bugs are mine. DETAILS 1 I added to each address family a pool of sockaddrs. I have introduced routines for allocating, copying, and duplicating, and freeing sockaddrs: struct sockaddr *sockaddr_alloc(sa_family_t af, int flags); struct sockaddr *sockaddr_copy(struct sockaddr *dst, const struct sockaddr *src); struct sockaddr *sockaddr_dup(const struct sockaddr *src, int flags); void sockaddr_free(struct sockaddr *sa); sockaddr_alloc() returns either a sockaddr from the pool belonging to the specified family, or NULL if the pool is exhausted. The returned sockaddr has the right size for that family; sa_family and sa_len fields are initialized to the family and sockaddr length---e.g., sa_family = AF_INET and sa_len = sizeof(struct sockaddr_in). sockaddr_free() puts the given sockaddr back into its family's pool. sockaddr_dup() and sockaddr_copy() work analogously to strdup() and strcpy(), respectively. sockaddr_copy() KASSERTs that the family of the destination and source sockaddrs are alike. The 'flags' argumet for sockaddr_alloc() and sockaddr_dup() is passed directly to pool_get(9). 2 I added routines for initializing sockaddrs in each address family, sockaddr_in_init(), sockaddr_in6_init(), sockaddr_iso_init(), etc. They are fairly self-explanatory. 3 structs route_in6 and route_iso are no more. All protocol families use struct route. I have changed the route cache, 'struct route', so that it does not contain storage space for a sockaddr. Instead, struct route points to a sockaddr coming from the pool the sockaddr belongs to. I added a new method to struct route, rtcache_setdst(), for setting the cache destination: int rtcache_setdst(struct route *, const struct sockaddr *); rtcache_setdst() returns 0 on success, or ENOMEM if no memory is available to create the sockaddr storage. It is now possible for rtcache_getdst() to return NULL if, say, rtcache_setdst() failed. I check the return value for NULL everywhere in the kernel. 4 Each routing domain (struct domain) has a list of live route caches, dom_rtcache. rtflushall(sa_family_t af) looks up the domain indicated by 'af', walks the domain's list of route caches and invalidates each one.
2007-05-03 00:40:22 +04:00
.dom_protoswNPROTOSW = &atalksw[__arraycount(atalksw)],
Here are various changes designed to protect against bad IPv4 routing caused by stale route caches (struct route). Route caches are sprinkled throughout PCBs, the IP fast-forwarding table, and IP tunnel interfaces (gre, gif, stf). Stale IPv6 and ISO route caches will be treated by separate patches. Thank you to Christoph Badura for suggesting the general approach to invalidating route caches that I take here. Here are the details: Add hooks to struct domain for tracking and for invalidating each domain's route caches: dom_rtcache, dom_rtflush, and dom_rtflushall. Introduce helper subroutines, rtflush(ro) for invalidating a route cache, rtflushall(family) for invalidating all route caches in a routing domain, and rtcache(ro) for notifying the domain of a new cached route. Chain together all IPv4 route caches where ro_rt != NULL. Provide in_rtcache() for adding a route to the chain. Provide in_rtflush() and in_rtflushall() for invalidating IPv4 route caches. In in_rtflush(), set ro_rt to NULL, and remove the route from the chain. In in_rtflushall(), walk the chain and remove every route cache. In rtrequest1(), call rtflushall() to invalidate route caches when a route is added. In gif(4), discard the workaround for stale caches that involves expiring them every so often. Replace the pattern 'RTFREE(ro->ro_rt); ro->ro_rt = NULL;' with a call to rtflush(ro). Update ipflow_fastforward() and all other users of route caches so that they expect a cached route, ro->ro_rt, to turn to NULL. Take care when moving a 'struct route' to rtflush() the source and to rtcache() the destination. In domain initializers, use .dom_xxx tags. KNF here and there.
2006-12-09 08:33:04 +03:00
.dom_rtattach = rn_inithead,
.dom_rtoffset = 32,
.dom_maxrtkey = sizeof(struct sockaddr_at),
.dom_ifattach = NULL,
.dom_ifdetach = NULL,
.dom_ifqueues = { &atintrq1, &atintrq2 },
.dom_link = { NULL },
.dom_mowner = MOWNER_INIT("",""),
.dom_sa_cmpofs = offsetof(struct sockaddr_at, sat_addr),
.dom_sa_cmplen = sizeof(struct at_addr),
.dom_rtcache = LIST_HEAD_INITIALIZER(atalkdomain.dom_rtcache)
};
Eliminate address family-specific route caches (struct route, struct route_in6, struct route_iso), replacing all caches with a struct route. The principle benefit of this change is that all of the protocol families can benefit from route cache-invalidation, which is necessary for correct routing. Route-cache invalidation fixes an ancient PR, kern/3508, at long last; it fixes various other PRs, also. Discussions with and ideas from Joerg Sonnenberger influenced this work tremendously. Of course, all design oversights and bugs are mine. DETAILS 1 I added to each address family a pool of sockaddrs. I have introduced routines for allocating, copying, and duplicating, and freeing sockaddrs: struct sockaddr *sockaddr_alloc(sa_family_t af, int flags); struct sockaddr *sockaddr_copy(struct sockaddr *dst, const struct sockaddr *src); struct sockaddr *sockaddr_dup(const struct sockaddr *src, int flags); void sockaddr_free(struct sockaddr *sa); sockaddr_alloc() returns either a sockaddr from the pool belonging to the specified family, or NULL if the pool is exhausted. The returned sockaddr has the right size for that family; sa_family and sa_len fields are initialized to the family and sockaddr length---e.g., sa_family = AF_INET and sa_len = sizeof(struct sockaddr_in). sockaddr_free() puts the given sockaddr back into its family's pool. sockaddr_dup() and sockaddr_copy() work analogously to strdup() and strcpy(), respectively. sockaddr_copy() KASSERTs that the family of the destination and source sockaddrs are alike. The 'flags' argumet for sockaddr_alloc() and sockaddr_dup() is passed directly to pool_get(9). 2 I added routines for initializing sockaddrs in each address family, sockaddr_in_init(), sockaddr_in6_init(), sockaddr_iso_init(), etc. They are fairly self-explanatory. 3 structs route_in6 and route_iso are no more. All protocol families use struct route. I have changed the route cache, 'struct route', so that it does not contain storage space for a sockaddr. Instead, struct route points to a sockaddr coming from the pool the sockaddr belongs to. I added a new method to struct route, rtcache_setdst(), for setting the cache destination: int rtcache_setdst(struct route *, const struct sockaddr *); rtcache_setdst() returns 0 on success, or ENOMEM if no memory is available to create the sockaddr storage. It is now possible for rtcache_getdst() to return NULL if, say, rtcache_setdst() failed. I check the return value for NULL everywhere in the kernel. 4 Each routing domain (struct domain) has a list of live route caches, dom_rtcache. rtflushall(sa_family_t af) looks up the domain indicated by 'af', walks the domain's list of route caches and invalidates each one.
2007-05-03 00:40:22 +04:00
int
sockaddr_at_cmp(const struct sockaddr *sa1, const struct sockaddr *sa2)
{
int rc;
uint_fast8_t len;
const uint_fast8_t addrofs = offsetof(struct sockaddr_at, sat_addr),
addrend = addrofs + sizeof(struct at_addr);
const struct sockaddr_at *sat1, *sat2;
sat1 = satocsat(sa1);
sat2 = satocsat(sa2);
len = MIN(addrend, MIN(sat1->sat_len, sat2->sat_len));
if (len > addrofs &&
(rc = memcmp(&sat1->sat_addr, &sat2->sat_addr, len - addrofs)) != 0)
return rc;
return sat1->sat_len - sat2->sat_len;
}