mir/isc-dhcp
2
0
Fork 0
mirror of https://gitlab.isc.org/isc-projects/dhcp synced 2025-08-31 14:25:41 +00:00
Code Issues Releases Wiki Activity

Handle hostnames that start with numbers.

Browse Source 
This involved needing to look at more than one token at a time, so
this patch moves from read() to mmap() of files, as a way to gracefully
rewind.

See RT ticket #16516 for (a lot) more.
This commit is contained in:
Shane Kerr
2007-05-23 15:29:49 +00:00
parent 6d7bdffcbd
commit 66eaae186e
3 changed files with 84 additions and 67 deletions
Download Patch File Download Diff File Expand all files Collapse all files

38
common/parse.c
View File

@@ -34,7 +34,7 @@
#ifndef lint
static char copyright[] =
"$Id: parse.c,v 1.124 2007/05/19 19:16:24 dhankins Exp $ Copyright (c) 2004-2007 Internet Systems Consortium. All rights reserved.\n";
"$Id: parse.c,v 1.125 2007/05/23 15:29:49 shane Exp $ Copyright (c) 2004-2007 Internet Systems Consortium. All rights reserved.\n";
#endif /* not lint */
#include "dhcpd.h"
@@ -257,7 +257,11 @@ char *parse_host_name (cfile)
Parse an ip address or a hostname. If uniform is zero, put in
an expr_substring node to limit hostnames that evaluate to more
than one IP address. */
than one IP address.
Note that RFC1123 permits hostnames to consist of all digits,
making it difficult to quickly disambiguate them from ip addresses.
*/
int parse_ip_addr_or_hostname (expr, cfile, uniform)
struct expression **expr;
@@ -270,9 +274,33 @@ int parse_ip_addr_or_hostname (expr, cfile, uniform)
unsigned len = sizeof addr;
char *name;
struct expression *x = (struct expression *)0;
struct parse cfile0;
int ipaddr = 0;
token = peek_token (&val, (unsigned *)0, cfile);
if (is_identifier (token)) {
if (token == NUMBER) {
/*
* a hostname may be numeric, but domain names must
* start with a letter, so we can disambiguate by
* looking ahead a few tokens. we save the parse
* context first, and restore it after we know what
* we're dealing with.
*/
memcpy(&cfile0, cfile, sizeof(struct parse));
(void) next_token(NULL, NULL, cfile);
if (next_token(NULL, NULL, cfile) == DOT &&
next_token(NULL, NULL, cfile) == NUMBER)
ipaddr = 1;
memcpy(cfile, &cfile0, sizeof(struct parse));
if (ipaddr &&
parse_numeric_aggregate (cfile, addr, &len, DOT, 10, 8))
return make_const_data (expr, addr, len, 0, 1, MDL);
}
if (is_identifier (token) || token == NUMBER) {
name = parse_host_name (cfile);
if (!name)
return 0;
@@ -287,10 +315,6 @@ int parse_ip_addr_or_hostname (expr, cfile, uniform)
expression_dereference (expr, MDL);
*expr = x;
}
} else if (token == NUMBER) {
if (!parse_numeric_aggregate (cfile, addr, &len, DOT, 10, 8))
return 0;
return make_const_data (expr, addr, len, 0, 1, MDL);
} else {
if (token != RBRACE && token != LBRACE)
token = next_token (&val, (unsigned *)0, cfile);