ComputerSurge/bind9
3
0
Fork 0
Code Pull Requests 1 Activity

RT #153: when invoked with type==CNAME and a message

Browse Source 
not constructed by dns_message_parse(), dns_message_findname() failed to
find anything due to checking for attribute bits set only by dns_message_parse().
This caused an infinite loop when constructing the response to an ANY query
at a CNAME in a secure zone.
This commit is contained in:
Andreas Gustafsson
2000-06-29 19:49:43 +00:00
parent 824068b85b
commit 428b78e56d
2 changed files with 62 additions and 21 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
CHANGES
View File

@@ -1,3 +1,12 @@
295. [bug] When invoked with type==CNAME and a message
not constructed by dns_message_parse(),
dns_message_findname() failed to find anything
due to checking for attribute bits that are set
only in dns_message_parse(). This caused an
infinite loop when constructing the response to
an ANY query at a CNAME in a secure zone.
294. [bug] If we run out of space in while processing glue
when reading a master file and commit "current name"
reverts to "name_current" instead of staying as

74
lib/dns/message.c
View File

@@ -15,7 +15,7 @@
* SOFTWARE.
*/
/* $Id: message.c,v 1.132 2000/06/29 18:58:32 gson Exp $ */
/* $Id: message.c,v 1.133 2000/06/29 19:47:58 gson Exp $ */
/***
*** Imports
@@ -737,6 +737,25 @@ dns_message_destroy(dns_message_t **msgp) {
isc_mem_put(msg->mctx, msg, sizeof(dns_message_t));
}
static isc_result_t
simple_findname(dns_name_t **foundname, dns_name_t *target,
dns_namelist_t *section)
{
dns_name_t *curr;
for (curr = ISC_LIST_TAIL(*section) ;
curr != NULL ;
curr = ISC_LIST_PREV(curr, link)) {
if (dns_name_equal(curr, target)) {
if (foundname != NULL)
*foundname = curr;
return (ISC_R_SUCCESS);
}
}
return (ISC_R_NOTFOUND);
}
static isc_result_t
findname(dns_name_t **foundname, dns_name_t *target, unsigned int attributes,
dns_namelist_t *section)
@@ -1983,8 +2002,6 @@ dns_message_findname(dns_message_t *msg, dns_section_t section,
{
dns_name_t *foundname;
isc_result_t result;
unsigned int attributes;
dns_rdatatype_t atype;
/*
* XXX These requirements are probably too intensive, especially
@@ -2004,24 +2021,39 @@ dns_message_findname(dns_message_t *msg, dns_section_t section,
REQUIRE(*rdataset == NULL);
}
/*
* Figure out what attributes we should look for.
*/
if (type == dns_rdatatype_sig)
atype = covers;
else
atype = type;
attributes = 0;
if (atype == dns_rdatatype_cname)
attributes = DNS_NAMEATTR_CNAME;
else if (atype == dns_rdatatype_dname)
attributes = DNS_NAMEATTR_DNAME;
/*
* Search through, looking for the name.
*/
result = findname(&foundname, target, attributes,
&msg->sections[section]);
if (msg->from_to_wire == DNS_MESSAGE_INTENTPARSE) {
dns_rdatatype_t atype;
unsigned int attributes;
/*
* Figure out what attributes we should look for.
*/
if (type == dns_rdatatype_sig)
atype = covers;
else
atype = type;
attributes = 0;
if (atype == dns_rdatatype_cname)
attributes = DNS_NAMEATTR_CNAME;
else if (atype == dns_rdatatype_cname)
attributes = DNS_NAMEATTR_DNAME;
/*
* Search through, looking for the name.
*/
result = findname(&foundname, target, attributes,
&msg->sections[section]);
} else {
/*
* The message was not built by dns_message_parse()
* and therefore does not have CNAMEs and DNAMEs
* as separate names, and no DNS_NAMEATTR_CNAME
* and DNS_NAMEATTR_DNAME attributes are maintained.
* Therefore, we should not compare attributes.
*/
result = simple_findname(&foundname, target,
&msg->sections[section]);
}
if (result == ISC_R_NOTFOUND)
return (DNS_R_NXDOMAIN);
else if (result != ISC_R_SUCCESS)