libcli/dns Improve dns_hosts_file, using Samba3's struct dns_rr_srv

By reworking the 'fake DNS' file to use struct dns_rr_srv it should be
possible to emulate that resolver layer as well as the Samba4
sockaddr_storage* based layer.  This will then give us a common DNS
emulation for 'make test'.

Andrew Bartlett

2 files changed, 2 insertions, 309 deletions

diff --git a/libcli/nbt/dns_hosts_file.c b/libcli/nbt/dns_hosts_file.c
deleted file mode 100644
index 801393650e..0000000000
--- a/libcli/nbt/dns_hosts_file.c
+++ /dev/null
@@ -1,307 +0,0 @@
-/*
-   Unix SMB/CIFS implementation.
-
-   read a file containing DNS names, types and IP addresses
-
-   Copyright (C) Andrew Tridgell 1994-1998
-   Copyright (C) Jeremy Allison 2007
-   Copyright (C) Andrew Bartlett 2009.
-
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-/* The purpose of this file is to read the file generated by the samba_dnsupdate script */
-
-#include "includes.h"
-#include "lib/util/xfile.h"
-#include "lib/util/util_net.h"
-#include "system/filesys.h"
-#include "system/network.h"
-#include "libcli/nbt/libnbt.h"
-
-/********************************************************
- Start parsing the dns_hosts_file file.
-*********************************************************/
-
-static XFILE *startdns_hosts_file(const char *fname)
-{
-	XFILE *fp = x_fopen(fname,O_RDONLY, 0);
-	if (!fp) {
-		DEBUG(4,("startdns_hosts_file: Can't open dns_hosts_file file %s. "
-			"Error was %s\n",
-			fname, strerror(errno)));
-		return NULL;
-	}
-	return fp;
-}
-
-/********************************************************
- Parse the next line in the dns_hosts_file file.
-*********************************************************/
-
-static bool getdns_hosts_fileent(TALLOC_CTX *ctx, XFILE *fp, char **pp_name, char **pp_name_type,
-			  char **pp_next_name, 
-			  struct sockaddr_storage *pss, uint32_t *p_port)
-{
-	char line[1024];
-
-	*pp_name = NULL;
-	*pp_name_type = NULL;
-	*pp_next_name = NULL;
-	*p_port = 0;
-
-	while(!x_feof(fp) && !x_ferror(fp)) {
-		char *name_type = NULL;
-		char *name = NULL;
-		char *next_name = NULL;
-		char *ip = NULL;
-		char *port = NULL;
-
-		const char *ptr;
-		int count = 0;
-
-		if (!fgets_slash(line,sizeof(line),fp)) {
-			continue;
-		}
-
-		if (*line == '#') {
-			continue;
-		}
-
-		ptr = line;
-
-		if (next_token_talloc(ctx, &ptr, &name_type, NULL))
-			++count;
-		if (next_token_talloc(ctx, &ptr, &name, NULL))
-			++count;
-		if (name_type && strcasecmp(name_type, "A") == 0) {
-			if (next_token_talloc(ctx, &ptr, &ip, NULL))
-				++count;
-		} else if (name_type && strcasecmp(name_type, "SRV") == 0) {
-			if (next_token_talloc(ctx, &ptr, &next_name, NULL))
-				++count;
-			if (next_token_talloc(ctx, &ptr, &port, NULL))
-				++count;
-		} else if (name_type && strcasecmp(name_type, "CNAME") == 0) {
-			if (next_token_talloc(ctx, &ptr, &next_name, NULL))
-				++count;
-		}
-		if (count <= 0)
-			continue;
-
-		if (strcasecmp(name_type, "A") == 0) {
-			if (count != 3) {
-				DEBUG(0,("getdns_hosts_fileent: Ill formed hosts A record [%s]\n",
-					 line));
-				continue;
-			}
-			DEBUG(4, ("getdns_hosts_fileent: host entry: %s %s %s\n",
-				  name_type, name, ip));
-			if (!interpret_string_addr(pss, ip, AI_NUMERICHOST)) {
-				DEBUG(0,("getdns_hosts_fileent: invalid address "
-					 "%s.\n", ip));
-			}
-
-		} else if (strcasecmp(name_type, "SRV") == 0) {
-			if (count != 4) {
-				DEBUG(0,("getdns_hosts_fileent: Ill formed hosts SRV record [%s]\n",
-					 line));
-				continue;
-			}
-			*p_port = strtoul(port, NULL, 10);
-			if (*p_port == UINT32_MAX) {
-				DEBUG(0, ("getdns_hosts_fileent: Ill formed hosts SRV record [%s] (invalid port: %s)\n",
-					  line, port));
-				continue;
-			}
-			DEBUG(4, ("getdns_hosts_fileent: host entry: %s %s %s %u\n",
-				  name_type, name, next_name, (unsigned int)*p_port));
-			*pp_next_name = talloc_strdup(ctx, next_name);
-			if (!*pp_next_name) {
-				return false;
-			}
-		} else if (strcasecmp(name_type, "CNAME") == 0) {
-			if (count != 3) {
-				DEBUG(0,("getdns_hosts_fileent: Ill formed hosts CNAME record [%s]\n",
-					 line));
-				continue;
-			}
-			DEBUG(4, ("getdns_hosts_fileent: host entry: %s %s %s\n",
-				  name_type, name, next_name));
-			*pp_next_name = talloc_strdup(ctx, next_name);
-			if (!*pp_next_name) {
-				return false;
-			}
-		} else {
-			DEBUG(0,("getdns_hosts_fileent: unknown type %s\n", name_type));
-			continue;
-		}
-
-		*pp_name = talloc_strdup(ctx, name);
-		if (!*pp_name) {
-			return false;
-		}
-
-		*pp_name_type = talloc_strdup(ctx, name_type);
-		if (!*pp_name_type) {
-			return false;
-		}
-		return true;
-	}
-
-	return false;
-}
-
-/********************************************************
- Finish parsing the dns_hosts_file file.
-*********************************************************/
-
-static void enddns_hosts_file(XFILE *fp)
-{
-	x_fclose(fp);
-}
-
-/********************************************************
- Resolve via "dns_hosts" method.
-*********************************************************/
-
-static NTSTATUS resolve_dns_hosts_file_as_sockaddr_recurse(const char *dns_hosts_file, 
-							   const char *name, bool srv_lookup,
-							   int level, uint32_t port, 
-							   TALLOC_CTX *mem_ctx, 
-							   struct sockaddr_storage **return_iplist,
-							   int *return_count)
-{
-	/*
-	 * "dns_hosts" means parse the local dns_hosts file.
-	 */
-
-	XFILE *fp;
-	char *host_name = NULL;
-	char *name_type = NULL;
-	char *next_name = NULL;
-	struct sockaddr_storage return_ss;
-	uint32_t srv_port;
-	NTSTATUS status = NT_STATUS_OBJECT_NAME_NOT_FOUND;
-	TALLOC_CTX *ctx = NULL;
-	TALLOC_CTX *ip_list_ctx = NULL;
-
-	/* Don't recurse forever, even on our own flat files */
-	if (level > 11) {
-
-	}
-
-	*return_iplist = NULL;
-	*return_count = 0;
-
-	DEBUG(3,("resolve_dns_hosts: "
-		"Attempting dns_hosts lookup for name %s\n",
-		name));
-
-	fp = startdns_hosts_file(dns_hosts_file);
-
-	if ( fp == NULL )
-		return NT_STATUS_OBJECT_NAME_NOT_FOUND;
-
-	ip_list_ctx = talloc_new(mem_ctx);
-	if (!ip_list_ctx) {
-		enddns_hosts_file(fp);
-		return NT_STATUS_NO_MEMORY;
-	}
-
-	ctx = talloc_new(ip_list_ctx);
-	if (!ctx) {
-		talloc_free(ip_list_ctx);
-		enddns_hosts_file(fp);
-		return NT_STATUS_NO_MEMORY;
-	}
-
-	while (getdns_hosts_fileent(ctx, fp, &host_name, &name_type, &next_name, &return_ss, &srv_port)) {
-		if (!strequal(name, host_name)) {
-			TALLOC_FREE(ctx);
-			ctx = talloc_new(mem_ctx);
-			if (!ctx) {
-				enddns_hosts_file(fp);
-				return NT_STATUS_NO_MEMORY;
-			}
-
-			continue;
-		}
-
-		if (srv_lookup) {
-			if (strcasecmp(name_type, "SRV") == 0) {
-				/* we only accept one host name per SRV entry */
-				enddns_hosts_file(fp);
-				status = resolve_dns_hosts_file_as_sockaddr_recurse(dns_hosts_file, next_name, 
-										    false, 
-										    level + 1, srv_port, 
-										    mem_ctx, return_iplist, 
-										    return_count);
-				talloc_free(ip_list_ctx);
-				return status;
-			} else {
-				continue;
-			}
-		} else if (strcasecmp(name_type, "CNAME") == 0) {
-			/* we only accept one host name per CNAME */
-			enddns_hosts_file(fp);
-			status = resolve_dns_hosts_file_as_sockaddr_recurse(dns_hosts_file, next_name, false, 
-									    level + 1, port, 
-									    mem_ctx, return_iplist, return_count);
-			talloc_free(ip_list_ctx);
-			return status;
-		} else if (strcasecmp(name_type, "A") == 0) {
-			/* Set the specified port (possibly from a SRV lookup) into the structure we return */
-			set_sockaddr_port((struct sockaddr *)&return_ss, port);
-
-			/* We are happy to keep looking for other possible A record matches */
-			*return_iplist = talloc_realloc(ip_list_ctx, (*return_iplist), 
-							struct sockaddr_storage,
-							(*return_count)+1);
-
-			if ((*return_iplist) == NULL) {
-				TALLOC_FREE(ctx);
-				enddns_hosts_file(fp);
-				DEBUG(3,("resolve_dns_hosts: talloc_realloc fail !\n"));
-				return NT_STATUS_NO_MEMORY;
-			}
-			
-			(*return_iplist)[*return_count] = return_ss;
-			*return_count += 1;
-			
-			/* we found something */
-			status = NT_STATUS_OK;
-		}
-	}
-
-	talloc_steal(mem_ctx, *return_iplist);
-	TALLOC_FREE(ip_list_ctx);
-	enddns_hosts_file(fp);
-	return status;
-}
-
-/********************************************************
- Resolve via "dns_hosts" method.
-*********************************************************/
-
-NTSTATUS resolve_dns_hosts_file_as_sockaddr(const char *dns_hosts_file, 
-					    const char *name, bool srv_lookup,
-					    TALLOC_CTX *mem_ctx, 
-					    struct sockaddr_storage **return_iplist,
-					    int *return_count)
-{
-	return resolve_dns_hosts_file_as_sockaddr_recurse(dns_hosts_file, name, srv_lookup, 
-							  0, 0, 
-							  mem_ctx, return_iplist, return_count);
-}
diff --git a/libcli/nbt/wscript_build b/libcli/nbt/wscript_build
index 6f7a1745b7..07d8c51b1f 100644
--- a/libcli/nbt/wscript_build
+++ b/libcli/nbt/wscript_build
@@ -7,13 +7,13 @@ bld.SAMBA_SUBSYSTEM('NDR_NBT_BUF',
 	)
 
 bld.SAMBA_SUBSYSTEM('lmhosts',
-                    source='lmhosts.c',
+                    source='lmhosts.c ../dns/dns_hosts_file.c',
                     deps='replace talloc'
                     )
 
 if bld.env._SAMBA_BUILD_ == 4:
     bld.SAMBA_LIBRARY('cli-nbt',
-                      source='nbtsocket.c namequery.c nameregister.c namerefresh.c namerelease.c dns_hosts_file.c',
+                      source='nbtsocket.c namequery.c nameregister.c namerefresh.c namerelease.c',
                       public_deps='ndr NDR_NBT tevent UTIL_TEVENT NDR_SECURITY samba_socket samba-util lmhosts',
                       private_library=True
                       )