Add nsswitch support. By creating an /etc/nsswitch.conf file, you can

configure FreeBSD so that various databases such as passwd and group can be
looked up using flat files, NIS, or Hesiod.

= Hesiod has been added to libc (see hesiod(3)).

= A library routine for parsing nsswitch.conf and invoking callback
  functions as specified has been added to libc (see nsdispatch(3)).

= The following C library functions have been modified to use nsdispatch:
    . getgrent, getgrnam, getgrgid
    . getpwent, getpwnam, getpwuid
    . getusershell
    . getaddrinfo
    . gethostbyname, gethostbyname2, gethostbyaddr
    . getnetbyname, getnetbyaddr
    . getipnodebyname, getipnodebyaddr, getnodebyname, getnodebyaddr

= host.conf has been removed from src/etc.  rc.network has been modified
  to warn that host.conf is no longer used at boot time.  In addition, if
  there is a host.conf but no nsswitch.conf, the latter is created at boot
  time from the former.

Obtained from:	NetBSD

1 files changed, 46 insertions, 120 deletions

diff --git a/lib/libc/net/gethostnamadr.c b/lib/libc/net/gethostnamadr.c
index 010e4db..fcfc979 100644
--- a/lib/libc/net/gethostnamadr.c
+++ b/lib/libc/net/gethostnamadr.c
@@ -37,87 +37,25 @@ static char rcsid[] = "$FreeBSD$";
 #include <ctype.h>
 #include <errno.h>
 #include <string.h>
+#include <stdarg.h>
+#include <nsswitch.h>
 #include <arpa/nameser.h>		/* XXX hack for _res */
 #include <resolv.h>			/* XXX hack for _res */
 
-#define _PATH_HOSTCONF	"/etc/host.conf"
-
-enum service_type {
-  SERVICE_NONE = 0,
-  SERVICE_BIND,
-  SERVICE_HOSTS,
-  SERVICE_NIS };
-#define SERVICE_MAX	SERVICE_NIS
-
-static struct {
-  const char *name;
-  enum service_type type;
-} service_names[] = {
-  { "hosts", SERVICE_HOSTS },
-  { "/etc/hosts", SERVICE_HOSTS },
-  { "hosttable", SERVICE_HOSTS },
-  { "htable", SERVICE_HOSTS },
-  { "bind", SERVICE_BIND },
-  { "dns", SERVICE_BIND },
-  { "domain", SERVICE_BIND },
-  { "yp", SERVICE_NIS },
-  { "yellowpages", SERVICE_NIS },
-  { "nis", SERVICE_NIS },
-  { 0, SERVICE_NONE }
+extern int _ht_gethostbyname(void *, void *, va_list);
+extern int _dns_gethostbyname(void *, void *, va_list);
+extern int _nis_gethostbyname(void *, void *, va_list);
+extern int _ht_gethostbyaddr(void *, void *, va_list);
+extern int _dns_gethostbyaddr(void *, void *, va_list);
+extern int _nis_gethostbyaddr(void *, void *, va_list);
+
+/* Host lookup order if nsswitch.conf is broken or nonexistant */
+static const ns_src default_src[] = { 
+	{ NSSRC_FILES, NS_SUCCESS },
+	{ NSSRC_DNS, NS_SUCCESS },
+	{ 0 }
 };
 
-static enum service_type service_order[SERVICE_MAX + 1];
-static int service_done = 0;
-
-static enum service_type
-get_service_name(const char *name) {
-	int i;
-	for(i = 0; service_names[i].type != SERVICE_NONE; i++) {
-		if(!strcasecmp(name, service_names[i].name)) {
-			return service_names[i].type;
-		}
-	}
-	return SERVICE_NONE;
-}
-
-static void
-init_services()
-{
-	char *cp, *p, buf[BUFSIZ];
-	register int cc = 0;
-	FILE *fd;
-
-	if ((fd = (FILE *)fopen(_PATH_HOSTCONF, "r")) == NULL) {
-				/* make some assumptions */
-		service_order[0] = SERVICE_BIND;
-		service_order[1] = SERVICE_HOSTS;
-		service_order[2] = SERVICE_NONE;
-	} else {
-		while (fgets(buf, BUFSIZ, fd) != NULL && cc < SERVICE_MAX) {
-			if(buf[0] == '#')
-				continue;
-
-			p = buf;
-			while ((cp = strsep(&p, "\n \t,:;")) != NULL && *cp == '\0')
-				;
-			if (cp == NULL)
-				continue;
-			do {
-				if (isalpha((unsigned char)cp[0])) {
-					service_order[cc] = get_service_name(cp);
-					if(service_order[cc] != SERVICE_NONE)
-						cc++;
-				}
-				while ((cp = strsep(&p, "\n \t,:;")) != NULL && *cp == '\0')
-					;
-			} while(cp != NULL && cc < SERVICE_MAX);
-		}
-		service_order[cc] = SERVICE_NONE;
-		fclose(fd);
-	}
-	service_done = 1;
-}
-
 struct hostent *
 gethostbyname(const char *name)
 {
@@ -135,56 +73,44 @@ struct hostent *
 gethostbyname2(const char *name, int type)
 {
 	struct hostent *hp = 0;
-	int nserv = 0;
-
-	if (!service_done)
-		init_services();
-
-	while (!hp) {
-		switch (service_order[nserv]) {
-		      case SERVICE_NONE:
-			return NULL;
-		      case SERVICE_HOSTS:
-			hp = _gethostbyhtname(name, type);
-			break;
-		      case SERVICE_BIND:
-			hp = _gethostbydnsname(name, type);
-			break;
-		      case SERVICE_NIS:
-			hp = _gethostbynisname(name, type);
-			break;
-		}
-		nserv++;
-	}
-	return hp;
+	int rval;
+
+	static const ns_dtab dtab[] = {
+		NS_FILES_CB(_ht_gethostbyname, NULL)
+		{ NSSRC_DNS, _dns_gethostbyname, NULL },
+		NS_NIS_CB(_nis_gethostbyname, NULL) /* force -DHESIOD */
+		{ 0 }
+	};       
+	
+	rval = nsdispatch((void *)&hp, dtab, NSDB_HOSTS, "gethostbyname",
+			  default_src, name, type);
+
+	if (rval != NS_SUCCESS)
+		return NULL;
+	else
+		return hp;
 }
 
 struct hostent *
 gethostbyaddr(const char *addr, int len, int type)
 {
 	struct hostent *hp = 0;
-	int nserv = 0;
-
-	if (!service_done)
-		init_services();
-
-	while (!hp) {
-		switch (service_order[nserv]) {
-		      case SERVICE_NONE:
-			return 0;
-		      case SERVICE_HOSTS:
-			hp = _gethostbyhtaddr(addr, len, type);
-			break;
-		      case SERVICE_BIND:
-			hp = _gethostbydnsaddr(addr, len, type);
-			break;
-		      case SERVICE_NIS:
-			hp = _gethostbynisaddr(addr, len, type);
-			break;
-		}
-		nserv++;
-	}
-	return hp;
+	int rval;
+
+	static const ns_dtab dtab[] = {
+		NS_FILES_CB(_ht_gethostbyaddr, NULL)
+		{ NSSRC_DNS, _dns_gethostbyaddr, NULL },
+		NS_NIS_CB(_nis_gethostbyaddr, NULL) /* force -DHESIOD */
+		{ 0 }
+	};       
+
+	rval = nsdispatch((void *)&hp, dtab, NSDB_HOSTS, "gethostbyaddr",
+			  default_src, addr, len, type);
+
+	if (rval != NS_SUCCESS)
+		return NULL;
+	else
+		return hp;
 }
 
 #ifdef _THREAD_SAFE