mir/bind
2
0
Fork 0
mirror of https://gitlab.isc.org/isc-projects/bind9 synced 2025-08-31 14:35:26 +00:00
Code Issues Releases Wiki Activity

508. [func] dns_message_parse() can now do a best-effort

Browse Source 
attempt, which should allow dig to print more invalid
                        messages.
This commit is contained in:
Brian Wellington
2000-10-06 18:58:30 +00:00
parent 4ed956c5c0
commit 6850cdd449
17 changed files with 143 additions and 95 deletions
Download Patch File Download Diff File Expand all files Collapse all files

122
lib/dns/message.c
View File

@@ -15,7 +15,7 @@
* WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/* $Id: message.c,v 1.146 2000/09/12 09:57:30 bwelling Exp $ */
/* $Id: message.c,v 1.147 2000/10/06 18:58:16 bwelling Exp $ */
/***
*** Imports
@@ -896,8 +896,19 @@ getrdata(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx,
}
}
#define DO_FORMERR \
do { \
if (best_effort) \
seen_problem = ISC_TRUE; \
else { \
result = DNS_R_FORMERR; \
goto cleanup; \
} \
} while (0)
static isc_result_t
getquestions(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx)
getquestions(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx,
unsigned int options)
{
isc_region_t r;
unsigned int count;
@@ -910,9 +921,13 @@ getquestions(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx)
dns_rdataclass_t rdclass;
dns_namelist_t *section;
isc_boolean_t free_name;
isc_boolean_t best_effort;
isc_boolean_t seen_problem;
section = &msg->sections[DNS_SECTION_QUESTION];
best_effort = ISC_TF(options & DNS_MESSAGEPARSE_BESTEFFORT);
name = NULL;
rdataset = NULL;
rdatalist = NULL;
@@ -954,10 +969,8 @@ getquestions(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx)
if (ISC_LIST_EMPTY(*section)) {
ISC_LIST_APPEND(*section, name, link);
free_name = ISC_FALSE;
} else {
result = DNS_R_FORMERR;
goto cleanup;
}
} else
DO_FORMERR;
} else {
isc_mempool_put(msg->namepool, name);
name = name2;
@@ -983,19 +996,15 @@ getquestions(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx)
if (msg->state == DNS_SECTION_ANY) {
msg->state = DNS_SECTION_QUESTION;
msg->rdclass = rdclass;
} else if (msg->rdclass != rdclass) {
result = DNS_R_FORMERR;
goto cleanup;
}
} else if (msg->rdclass != rdclass)
DO_FORMERR;
/*
* Can't ask the same question twice.
*/
result = dns_message_findtype(name, rdtype, 0, NULL);
if (result == ISC_R_SUCCESS) {
result = DNS_R_FORMERR;
goto cleanup;
}
if (result == ISC_R_SUCCESS)
DO_FORMERR;
/*
* Allocate a new rdatalist.
@@ -1032,6 +1041,8 @@ getquestions(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx)
rdataset = NULL;
}
if (seen_problem)
return (DNS_R_RECOVERABLE);
return (ISC_R_SUCCESS);
cleanup:
@@ -1051,7 +1062,7 @@ getquestions(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx)
static isc_result_t
getsection(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx,
dns_section_t sectionid, isc_boolean_t preserve_order)
dns_section_t sectionid, unsigned int options)
{
isc_region_t r;
unsigned int count, rdatalen;
@@ -1066,6 +1077,10 @@ getsection(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx,
dns_ttl_t ttl;
dns_namelist_t *section;
isc_boolean_t free_name, free_rdataset;
isc_boolean_t preserve_order, best_effort, seen_problem;
preserve_order = ISC_TF(options & DNS_MESSAGEPARSE_PRESERVEORDER);
best_effort = ISC_TF(options & DNS_MESSAGEPARSE_BESTEFFORT);
for (count = 0 ; count < msg->counts[sectionid] ; count++) {
int recstart = source->current;
@@ -1111,10 +1126,8 @@ getsection(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx,
*/
if (msg->state == DNS_SECTION_ANY) {
if ((msg->opcode != dns_opcode_update) &&
(rdclass == 0 || rdclass == dns_rdataclass_any)) {
result = DNS_R_FORMERR;
goto cleanup;
}
(rdclass == 0 || rdclass == dns_rdataclass_any))
DO_FORMERR;
msg->rdclass = rdclass;
msg->state = DNS_SECTION_QUESTION;
}
@@ -1128,10 +1141,8 @@ getsection(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx,
&& rdtype != dns_rdatatype_opt
&& rdtype != dns_rdatatype_key /* XXX in a TKEY query */
&& rdtype != dns_rdatatype_sig /* XXX SIG(0) */
&& msg->rdclass != rdclass) {
result = DNS_R_FORMERR;
goto cleanup;
}
&& msg->rdclass != rdclass)
DO_FORMERR;
/*
* Special type handling for TSIG, OPT, and TKEY.
@@ -1143,10 +1154,8 @@ getsection(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx,
* the rest of this rdata.
*/
if ((sectionid != DNS_SECTION_ADDITIONAL)
|| (rdclass != dns_rdataclass_any)) {
result = DNS_R_FORMERR;
goto cleanup;
}
|| (rdclass != dns_rdataclass_any))
DO_FORMERR;
if (msg->tsig != NULL) {
result = DNS_R_FORMERR;
goto cleanup;
@@ -1161,8 +1170,9 @@ getsection(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx,
* it must be the first OPT we've seen.
*/
if (!dns_name_equal(dns_rootname, name) ||
sectionid != DNS_SECTION_ADDITIONAL ||
msg->opt != NULL) {
msg->opt != NULL)
DO_FORMERR;
if (msg->opt != NULL) {
result = DNS_R_FORMERR;
goto cleanup;
}
@@ -1181,10 +1191,8 @@ getsection(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx,
tkeysection = DNS_SECTION_ADDITIONAL;
else
tkeysection = DNS_SECTION_ANSWER;
if (sectionid != tkeysection) {
result = DNS_R_FORMERR;
goto cleanup;
}
if (sectionid != tkeysection)
DO_FORMERR;
}
/*
@@ -1303,10 +1311,8 @@ getsection(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx,
* the opcode is an update, or the type search is skipped.
*/
if (result == ISC_R_SUCCESS) {
if (dns_rdatatype_issingleton(rdtype)) {
result = DNS_R_FORMERR;
goto cleanup;
}
if (dns_rdatatype_issingleton(rdtype))
DO_FORMERR;
}
if (result == ISC_R_NOTFOUND) {
@@ -1403,6 +1409,8 @@ getsection(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx,
INSIST(free_rdataset == ISC_FALSE);
}
if (seen_problem)
return (DNS_R_RECOVERABLE);
return (ISC_R_SUCCESS);
cleanup:
@@ -1416,18 +1424,22 @@ getsection(isc_buffer_t *source, dns_message_t *msg, dns_decompress_t *dctx,
isc_result_t
dns_message_parse(dns_message_t *msg, isc_buffer_t *source,
isc_boolean_t preserve_order)
unsigned int options)
{
isc_region_t r;
dns_decompress_t dctx;
isc_result_t ret;
isc_uint16_t tmpflags;
isc_buffer_t origsource;
isc_boolean_t best_effort;
isc_boolean_t seen_problem;
REQUIRE(DNS_MESSAGE_VALID(msg));
REQUIRE(source != NULL);
REQUIRE(msg->from_to_wire == DNS_MESSAGE_INTENTPARSE);
best_effort = ISC_TF(options & DNS_MESSAGEPARSE_BESTEFFORT);
origsource = *source;
msg->header_ok = 0;
@@ -1457,23 +1469,36 @@ dns_message_parse(dns_message_t *msg, isc_buffer_t *source,
dns_decompress_setmethods(&dctx, DNS_COMPRESS_GLOBAL14);
ret = getquestions(source, msg, &dctx);
ret = getquestions(source, msg, &dctx, options);
if (ret == DNS_R_RECOVERABLE) {
seen_problem = ISC_TRUE;
ret = ISC_R_SUCCESS;
}
if (ret != ISC_R_SUCCESS)
return (ret);
msg->question_ok = 1;
ret = getsection(source, msg, &dctx, DNS_SECTION_ANSWER,
preserve_order);
ret = getsection(source, msg, &dctx, DNS_SECTION_ANSWER, options);
if (ret == DNS_R_RECOVERABLE) {
seen_problem = ISC_TRUE;
ret = ISC_R_SUCCESS;
}
if (ret != ISC_R_SUCCESS)
return (ret);
ret = getsection(source, msg, &dctx, DNS_SECTION_AUTHORITY,
preserve_order);
ret = getsection(source, msg, &dctx, DNS_SECTION_AUTHORITY, options);
if (ret == DNS_R_RECOVERABLE) {
seen_problem = ISC_TRUE;
ret = ISC_R_SUCCESS;
}
if (ret != ISC_R_SUCCESS)
return (ret);
ret = getsection(source, msg, &dctx, DNS_SECTION_ADDITIONAL,
preserve_order);
ret = getsection(source, msg, &dctx, DNS_SECTION_ADDITIONAL, options);
if (ret == DNS_R_RECOVERABLE) {
seen_problem = ISC_TRUE;
ret = ISC_R_SUCCESS;
}
if (ret != ISC_R_SUCCESS)
return (ret);
@@ -1484,7 +1509,10 @@ dns_message_parse(dns_message_t *msg, isc_buffer_t *source,
DNS_LOGMODULE_MESSAGE, ISC_LOG_INFO,
"message has nonstandard Microsoft tag");
} else {
return (DNS_R_FORMERR);
if (best_effort)
seen_problem = ISC_TRUE;
else
return (DNS_R_FORMERR);
}
}
@@ -1502,6 +1530,8 @@ dns_message_parse(dns_message_t *msg, isc_buffer_t *source,
}
memcpy(msg->saved->base, r.base, msg->saved->length);
if (seen_problem == ISC_TRUE)
return (DNS_R_RECOVERABLE);
return (ISC_R_SUCCESS);
}