Aren/NetBSD
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

rewrite local address detection code, to use getifaddrs(3), not gethostname(3).

Browse Source 
gethostname(3) do not necessarily represent local host addrses.
pointed out by: Chuck Cranor
This commit is contained in:
itojun 2000-08-09 14:28:50 +00:00
parent 14e83027c8
commit f714bfb0d8
1 changed files with 78 additions and 54 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

132
usr.sbin/lpr/common_source/common.c
View File

@ -1,4 +1,4 @@
/* $NetBSD: common.c,v 1.20 2000/04/25 02:34:49 itojun Exp $ */ /* $NetBSD: common.c,v 1.21 2000/08/09 14:28:50 itojun Exp $ */
/* /*
* Copyright (c) 1983, 1993 * Copyright (c) 1983, 1993
@ -43,7 +43,7 @@
#if 0 #if 0
static char sccsid[] = "@(#)common.c 8.5 (Berkeley) 4/28/95"; static char sccsid[] = "@(#)common.c 8.5 (Berkeley) 4/28/95";
#else #else
__RCSID("$NetBSD: common.c,v 1.20 2000/04/25 02:34:49 itojun Exp $"); __RCSID("$NetBSD: common.c,v 1.21 2000/08/09 14:28:50 itojun Exp $");
#endif #endif
#endif /* not lint */ #endif /* not lint */
@ -62,6 +62,7 @@ __RCSID("$NetBSD: common.c,v 1.20 2000/04/25 02:34:49 itojun Exp $");
#include <stdlib.h> #include <stdlib.h>
#include <stdio.h> #include <stdio.h>
#include <string.h> #include <string.h>
#include <ifaddrs.h>
#include "lp.h" #include "lp.h"
#include "pathnames.h" #include "pathnames.h"
@ -303,68 +304,91 @@ compar(p1, p2)
/* /*
* Figure out whether the local machine is the same * Figure out whether the local machine is the same
* as the remote machine (RM) entry (if it exists). * as the remote machine (RM) entry (if it exists).
*
* XXX not really the right way to determine.
*/ */
char * char *
checkremote() checkremote()
{ {
char hname[NI_MAXHOST]; char lname[NI_MAXHOST], rname[NI_MAXHOST];
struct addrinfo hints, *res; struct addrinfo hints, *res, *res0;
static char errbuf[128]; static char errbuf[128];
int error; int error;
struct ifaddrs *ifap, *ifa;
#ifdef NI_WITHSCOPEID
const int niflags = NI_NUMERICHOST | NI_WITHSCOPEID;
#else
const int niflags = NI_NUMERICHOST;
#endif
#ifdef __KAME__
struct sockaddr_in6 sin6;
struct sockaddr_in6 *sin6p;
#endif
remote = 0; /* assume printer is local */ remote = 0; /* assume printer is local on failure */
if (RM != NULL) {
/* get the official name of the local host */
gethostname(hname, sizeof(hname));
hname[sizeof(hname)-1] = '\0';
memset(&hints, 0, sizeof(hints)); if (RM == NULL)
hints.ai_flags = AI_CANONNAME; return NULL;
hints.ai_family = PF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
res = NULL;
error = getaddrinfo(hname, NULL, &hints, &res);
if (error || !res->ai_canonname) {
(void)snprintf(errbuf, sizeof(errbuf),
"unable to get official name for local machine %s: "
"%s", hname, gai_strerror(error));
if (res)
freeaddrinfo(res);
return errbuf;
} else {
(void)strncpy(hname, res->ai_canonname,
sizeof(hname) - 1);
hname[sizeof(hname) - 1] = '\0';
}
freeaddrinfo(res);
/* get the official name of RM */ /* get the local interface addresses */
memset(&hints, 0, sizeof(hints)); if (getifaddrs(&ifap) < 0) {
hints.ai_flags = AI_CANONNAME; (void)snprintf(errbuf, sizeof(errbuf),
hints.ai_family = PF_UNSPEC; "unable to get local interface address: %s",
hints.ai_socktype = SOCK_STREAM; strerror(errno));
res = NULL; return errbuf;
error = getaddrinfo(RM, NULL, &hints, &res);
if (error || !res->ai_canonname) {
(void)snprintf(errbuf, sizeof(errbuf),
"unable to get official name for local machine %s: "
"%s", RM, gai_strerror(error));
if (res)
freeaddrinfo(res);
return errbuf;
}
/*
* if the two hosts are not the same,
* then the printer must be remote.
*/
if (strcasecmp(hname, res->ai_canonname) != 0)
remote = 1;
freeaddrinfo(res);
} }
/* get the remote host addresses (RM) */
memset(&hints, 0, sizeof(hints));
hints.ai_flags = AI_CANONNAME;
hints.ai_family = PF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
res = NULL;
error = getaddrinfo(RM, NULL, &hints, &res0);
if (error) {
(void)snprintf(errbuf, sizeof(errbuf),
"unable to resolve remote machine %s: %s",
RM, gai_strerror(error));
freeifaddrs(ifap);
return errbuf;
}
remote = 1; /* assume printer is remote */
for (res = res0; res; res = res->ai_next) {
if (getnameinfo(res->ai_addr, res->ai_addrlen,
rname, sizeof(rname), NULL, 0, niflags) != 0)
continue;
for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
#ifdef __KAME__
sin6p = (struct sockaddr_in6 *)ifa->ifa_addr;
if (ifa->ifa_addr->sa_family == AF_INET6 &&
ifa->ifa_addr->sa_len == sizeof(sin6) &&
IN6_IS_ADDR_LINKLOCAL(&sin6p->sin6_addr) &&
*(u_int16_t *)&sin6p->sin6_addr.s6_addr[2]) {
/* kame scopeid hack */
memcpy(&sin6, ifa->ifa_addr, sizeof(sin6));
sin6.sin6_scope_id =
ntohs(*(u_int16_t *)&sin6p->sin6_addr.s6_addr[2]);
sin6.sin6_addr.s6_addr[2] = 0;
sin6.sin6_addr.s6_addr[3] = 0;
if (getnameinfo((struct sockaddr *)&sin6,
sin6.sin6_len, lname, sizeof(lname),
NULL, 0, niflags) != 0)
continue;
} else
#endif
if (getnameinfo(ifa->ifa_addr, ifa->ifa_addr->sa_len,
lname, sizeof(lname), NULL, 0, niflags) != 0)
continue;
if (strcmp(rname, lname) == 0) {
remote = 0;
goto done;
}
}
}
done:
freeaddrinfo(res0);
freeifaddrs(ifap);
return NULL; return NULL;
} }