unbound/contrib/redirect-bogus.patch
Ralph Dolmans 6132c9f8d5 - Added redirect-bogus.patch to contrib directory.
git-svn-id: file:///svn/unbound/trunk@4194 be551aaa-1e26-0410-a405-d3ace91eadb9
2017-05-26 12:09:38 +00:00

345 lines
13 KiB
Diff

Index: daemon/worker.c
===================================================================
--- daemon/worker.c (revision 4191)
+++ daemon/worker.c (working copy)
@@ -663,8 +663,21 @@
if(!inplace_cb_reply_servfail_call(&worker->env, qinfo, NULL, rep,
LDNS_RCODE_SERVFAIL, edns, worker->scratchpad))
goto bail_out;
- error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
- qinfo, id, flags, edns);
+ if (qinfo->qtype == LDNS_RR_TYPE_A &&
+ worker->env.cfg->redirect_bogus_ipv4) {
+ /* BAD cached */
+ fixed_address_encode(repinfo->c->buffer,
+ LDNS_RCODE_NOERROR, qinfo, id, flags, edns,
+ worker->env.cfg->redirect_bogus_ipv4);
+ } else if (qinfo->qtype == LDNS_RR_TYPE_AAAA &&
+ worker->env.cfg->redirect_bogus_ipv6) {
+ fixed_address_encode(repinfo->c->buffer,
+ LDNS_RCODE_NOERROR, qinfo, id, flags, edns,
+ worker->env.cfg->redirect_bogus_ipv6);
+ } else {
+ error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
+ qinfo, id, flags, edns);
+ }
rrset_array_unlock_touch(worker->env.rrset_cache,
worker->scratchpad, rep->ref, rep->rrset_count);
if(worker->stats.extended) {
Index: doc/unbound.conf.5.in
===================================================================
--- doc/unbound.conf.5.in (revision 4191)
+++ doc/unbound.conf.5.in (working copy)
@@ -1244,6 +1244,18 @@
This can make ordinary queries complete (if repeatedly queried for),
and enter the cache, whilst also mitigating the traffic flow by the
factor given.
+.TP 5
+.B redirect-bogus-ipv4: \fI<IPv4 address>
+Set a fixed address for DNSSEC failures that are cached
+Instead of responding to A queries with SERVFAIL, respond
+with NOERROR and the address specified here
+The TTL of the response will be 5 seconds
+.TP 5
+.B redirect-bogus-ipv6: \fI<IPv4 address>
+Set a fixed address for DNSSEC failures that are cached
+Instead of responding to AAAA queries with SERVFAIL, respond
+with NOERROR and the address specified here
+The TTL of the response will be 5 seconds
.SS "Remote Control Options"
In the
.B remote\-control:
Index: services/mesh.c
===================================================================
--- services/mesh.c (revision 4191)
+++ services/mesh.c (working copy)
@@ -1006,6 +1006,7 @@
struct timeval end_time;
struct timeval duration;
int secure;
+ int bogus_override = 0;
/* Copy the client's EDNS for later restore, to make sure the edns
* compare is with the correct edns options. */
struct edns_data edns_bak = r->edns;
@@ -1016,6 +1017,7 @@
rcode = LDNS_RCODE_SERVFAIL;
if(m->s.env->cfg->stat_extended)
m->s.env->mesh->ans_bogus++;
+ bogus_override = 1;
}
if(rep && rep->security == sec_status_secure)
secure = 1;
@@ -1047,17 +1049,34 @@
} else if(rcode) {
m->s.qinfo.qname = r->qname;
m->s.qinfo.local_alias = r->local_alias;
- if(rcode == LDNS_RCODE_SERVFAIL) {
- if(!inplace_cb_reply_servfail_call(m->s.env, &m->s.qinfo, &m->s,
- rep, rcode, &r->edns, m->s.region))
- r->edns.opt_list = NULL;
- } else {
- if(!inplace_cb_reply_call(m->s.env, &m->s.qinfo, &m->s, rep, rcode,
- &r->edns, m->s.region))
- r->edns.opt_list = NULL;
+ if(bogus_override && m->s.qinfo.qtype == LDNS_RR_TYPE_A &&
+ m->s.env->cfg->redirect_bogus_ipv4) {
+ fixed_address_encode(r->query_reply.c->buffer,
+ LDNS_RCODE_NOERROR, &m->s.qinfo, r->qid,
+ r->qflags, &r->edns,
+ m->s.env->cfg->redirect_bogus_ipv4);
+ } else if(bogus_override &&
+ m->s.qinfo.qtype == LDNS_RR_TYPE_AAAA &&
+ m->s.env->cfg->redirect_bogus_ipv6) {
+ fixed_address_encode(r->query_reply.c->buffer,
+ LDNS_RCODE_NOERROR, &m->s.qinfo, r->qid,
+ r->qflags, &r->edns,
+ m->s.env->cfg->redirect_bogus_ipv6);
+ } else {
+ if(rcode == LDNS_RCODE_SERVFAIL) {
+ if(!inplace_cb_reply_servfail_call(m->s.env,
+ &m->s.qinfo, &m->s,
+ rep, rcode, &r->edns, m->s.region))
+ r->edns.opt_list = NULL;
+ } else {
+ if(!inplace_cb_reply_call(m->s.env, &m->s.qinfo,
+ &m->s, rep, rcode, &r->edns,
+ m->s.region))
+ r->edns.opt_list = NULL;
+ }
+ error_encode(r->query_reply.c->buffer, rcode,
+ &m->s.qinfo, r->qid, r->qflags, &r->edns);
}
- error_encode(r->query_reply.c->buffer, rcode, &m->s.qinfo,
- r->qid, r->qflags, &r->edns);
comm_point_send_reply(&r->query_reply);
} else {
size_t udp_size = r->edns.udp_size;
Index: util/config_file.c
===================================================================
--- util/config_file.c (revision 4191)
+++ util/config_file.c (working copy)
@@ -273,6 +273,8 @@
cfg->ratelimit_factor = 10;
cfg->qname_minimisation = 0;
cfg->qname_minimisation_strict = 0;
+ cfg->redirect_bogus_ipv4 = NULL;
+ cfg->redirect_bogus_ipv6 = NULL;
cfg->shm_enable = 0;
cfg->shm_key = 11777;
cfg->dnscrypt = 0;
@@ -602,6 +604,10 @@
}
oi[cfg->num_out_ifs++] = d;
cfg->out_ifs = oi;
+ } else if (strcmp(opt, "redirect-bogus-ipv4:") == 0) {
+ cfg->redirect_bogus_ipv4 = strdup(val);
+ } else if (strcmp(opt, "redirect-bogus-ipv6:") == 0) {
+ cfg->redirect_bogus_ipv6 = strdup(val);
} else {
/* unknown or unsupported (from the set_option interface):
* interface, outgoing-interface, access-control,
@@ -1250,6 +1256,12 @@
free(cfg->dnstap_version);
config_deldblstrlist(cfg->ratelimit_for_domain);
config_deldblstrlist(cfg->ratelimit_below_domain);
+ if (cfg->redirect_bogus_ipv4) {
+ free(cfg->redirect_bogus_ipv4);
+ }
+ if (cfg->redirect_bogus_ipv6) {
+ free(cfg->redirect_bogus_ipv6);
+ }
#ifdef USE_IPSECMOD
free(cfg->ipsecmod_hook);
config_delstrlist(cfg->ipsecmod_whitelist);
Index: util/config_file.h
===================================================================
--- util/config_file.h (revision 4191)
+++ util/config_file.h (working copy)
@@ -444,6 +444,9 @@
/** minimise QNAME in strict mode, minimise according to RFC.
* Do not apply fallback */
int qname_minimisation_strict;
+ /** construct fake responses for DNSSEC failures */
+ char *redirect_bogus_ipv4;
+ char *redirect_bogus_ipv6;
/** SHM data - true if shm is enabled */
int shm_enable;
/** SHM data - key for the shm */
Index: util/configlexer.lex
===================================================================
--- util/configlexer.lex (revision 4191)
+++ util/configlexer.lex (working copy)
@@ -410,6 +410,8 @@
response-ip-tag{COLON} { YDVAR(2, VAR_RESPONSE_IP_TAG) }
response-ip{COLON} { YDVAR(2, VAR_RESPONSE_IP) }
response-ip-data{COLON} { YDVAR(2, VAR_RESPONSE_IP_DATA) }
+redirect-bogus-ipv4{COLON} { YDVAR(1, VAR_REDIRECT_BOGUS_IPV4) }
+redirect-bogus-ipv6{COLON} { YDVAR(1, VAR_REDIRECT_BOGUS_IPV6) }
dnscrypt{COLON} { YDVAR(0, VAR_DNSCRYPT) }
dnscrypt-enable{COLON} { YDVAR(1, VAR_DNSCRYPT_ENABLE) }
dnscrypt-port{COLON} { YDVAR(1, VAR_DNSCRYPT_PORT) }
Index: util/configparser.y
===================================================================
--- util/configparser.y (revision 4191)
+++ util/configparser.y (working copy)
@@ -44,6 +44,7 @@
#include <stdlib.h>
#include <assert.h>
+#include "sldns/str2wire.h"
#include "util/configyyrename.h"
#include "util/config_file.h"
#include "util/net_help.h"
@@ -141,6 +142,7 @@
%token VAR_ACCESS_CONTROL_TAG_DATA VAR_VIEW VAR_ACCESS_CONTROL_VIEW
%token VAR_VIEW_FIRST VAR_SERVE_EXPIRED VAR_FAKE_DSA VAR_FAKE_SHA1
%token VAR_LOG_IDENTITY VAR_HIDE_TRUSTANCHOR VAR_TRUST_ANCHOR_SIGNALING
+%token VAR_REDIRECT_BOGUS_IPV4 VAR_REDIRECT_BOGUS_IPV6
%token VAR_USE_SYSTEMD VAR_SHM_ENABLE VAR_SHM_KEY
%token VAR_DNSCRYPT VAR_DNSCRYPT_ENABLE VAR_DNSCRYPT_PORT VAR_DNSCRYPT_PROVIDER
%token VAR_DNSCRYPT_SECRET_KEY VAR_DNSCRYPT_PROVIDER_CERT
@@ -228,6 +230,7 @@
server_access_control_tag_data | server_access_control_view |
server_qname_minimisation_strict | server_serve_expired |
server_fake_dsa | server_log_identity | server_use_systemd |
+ server_redirect_bogus_ipv4 | server_redirect_bogus_ipv6 |
server_response_ip_tag | server_response_ip | server_response_ip_data |
server_shm_enable | server_shm_key | server_fake_sha1 |
server_hide_trustanchor | server_trust_anchor_signaling |
@@ -1873,6 +1876,34 @@
#endif
}
;
+server_redirect_bogus_ipv4: VAR_REDIRECT_BOGUS_IPV4 STRING_ARG
+ {
+ uint8_t data[4];
+ size_t data_len = 4;
+ OUTYY(("P(name:%s)\n", $2));
+ if(cfg_parser->cfg->redirect_bogus_ipv4) {
+ yyerror("redirect-bogus-ipv4, can only use one address");
+ }
+ if(sldns_str2wire_a_buf($2, data, &data_len) != LDNS_WIREPARSE_ERR_OK) {
+ yyerror("redirect-bogus-ipv4, not a valid IPv4 address");
+ }
+ free(cfg_parser->cfg->redirect_bogus_ipv4);
+ cfg_parser->cfg->redirect_bogus_ipv4 = $2;
+ }
+server_redirect_bogus_ipv6: VAR_REDIRECT_BOGUS_IPV6 STRING_ARG
+ {
+ uint8_t data[16];
+ size_t data_len = 16;
+ OUTYY(("P(name:%s)\n", $2));
+ if(cfg_parser->cfg->redirect_bogus_ipv6) {
+ yyerror("redirect-bogus-ipv6, can only use one address");
+ }
+ if(sldns_str2wire_aaaa_buf($2, data, &data_len) != LDNS_WIREPARSE_ERR_OK) {
+ yyerror("redirect-bogus-ipv6, not a valid IPv6 address");
+ }
+ free(cfg_parser->cfg->redirect_bogus_ipv6);
+ cfg_parser->cfg->redirect_bogus_ipv6 = $2;
+ }
stub_name: VAR_NAME STRING_ARG
{
OUTYY(("P(name:%s)\n", $2));
Index: util/data/msgencode.c
===================================================================
--- util/data/msgencode.c (revision 4191)
+++ util/data/msgencode.c (working copy)
@@ -48,6 +48,7 @@
#include "util/regional.h"
#include "util/net_help.h"
#include "sldns/sbuffer.h"
+#include "sldns/str2wire.h"
#include "services/localzone.h"
/** return code that means the function ran out of memory. negative so it does
@@ -914,3 +915,63 @@
attach_edns_record(buf, &es);
}
}
+
+void
+fixed_address_encode(sldns_buffer* buf, int r, struct query_info* qinfo,
+ uint16_t qid, uint16_t qflags, struct edns_data* edns, char* data)
+{
+ uint16_t flags;
+ uint8_t addr_data[16];
+ size_t addr_len = 16;
+ if (qinfo->qtype == LDNS_RR_TYPE_A) {
+ sldns_str2wire_a_buf(data, addr_data, &addr_len);
+ } else if (qinfo->qtype == LDNS_RR_TYPE_AAAA) {
+ sldns_str2wire_aaaa_buf(data, addr_data, &addr_len);
+ } else {
+ return error_encode(buf, LDNS_RCODE_NOERROR, qinfo, qid, qflags, edns);
+ }
+ sldns_buffer_clear(buf);
+ sldns_buffer_write(buf, &qid, sizeof(uint16_t));
+ flags = (uint16_t)(BIT_QR | BIT_RA | r); /* QR and retcode*/
+ flags |= (qflags & (BIT_RD|BIT_CD)); /* copy RD and CD bit */
+ sldns_buffer_write_u16(buf, flags);
+ if(qinfo) flags = 1;
+ else flags = 0;
+ sldns_buffer_write_u16(buf, flags);
+ sldns_buffer_write_u16(buf, 1);
+ flags = 0;
+ sldns_buffer_write(buf, &flags, sizeof(uint16_t));
+ sldns_buffer_write(buf, &flags, sizeof(uint16_t));
+ if(qinfo) {
+ // query
+ if(sldns_buffer_current(buf) == qinfo->qname)
+ sldns_buffer_skip(buf, (ssize_t)qinfo->qname_len);
+ else sldns_buffer_write(buf, qinfo->qname, qinfo->qname_len);
+ sldns_buffer_write_u16(buf, qinfo->qtype);
+ sldns_buffer_write_u16(buf, qinfo->qclass);
+ // faked answer
+ if(sldns_buffer_current(buf) == qinfo->qname)
+ sldns_buffer_skip(buf, (ssize_t)qinfo->qname_len);
+ else sldns_buffer_write(buf, qinfo->qname, qinfo->qname_len);
+ sldns_buffer_write_u16(buf, qinfo->qtype);
+ sldns_buffer_write_u16(buf, qinfo->qclass);
+ sldns_buffer_write_u16(buf, 0);
+ // TTL. Should we make this configurable too?
+ sldns_buffer_write_u16(buf, 5);
+ sldns_buffer_write_u16(buf, addr_len);
+ sldns_buffer_write(buf, addr_data, addr_len);
+ fflush(stderr);
+ }
+ sldns_buffer_flip(buf);
+ if(edns) {
+ struct edns_data es = *edns;
+ es.edns_version = EDNS_ADVERTISED_VERSION;
+ es.udp_size = EDNS_ADVERTISED_SIZE;
+ es.ext_rcode = 0;
+ es.bits &= EDNS_DO;
+ if(sldns_buffer_limit(buf) + calc_edns_field_size(&es) >
+ edns->udp_size)
+ return;
+ attach_edns_record(buf, &es);
+ }
+}
Index: util/data/msgencode.h
===================================================================
--- util/data/msgencode.h (revision 4191)
+++ util/data/msgencode.h (working copy)
@@ -128,4 +128,20 @@
void error_encode(struct sldns_buffer* pkt, int r, struct query_info* qinfo,
uint16_t qid, uint16_t qflags, struct edns_data* edns);
+/**
+ * Encode a fixed address response.
+ * This is a fake answer to either an A or AAA query
+ *
+ * It will answer with that address
+ *
+ * @param pkt: where to store the packet.
+ * @param r: RCODE value to encode.
+ * @param qinfo: if not NULL, the query is included.
+ * @param qid: query ID to set in packet. network order.
+ * @param qflags: original query flags (to copy RD and CD bits). host order.
+ * @param edns: if not NULL, this is the query edns info,
+ * and an edns reply is attached. Only attached if EDNS record fits reply.
+ */
+void fixed_address_encode(struct sldns_buffer* pkt, int r, struct query_info* qinfo,
+ uint16_t qid, uint16_t qflags, struct edns_data* edns, char* address);
#endif /* UTIL_DATA_MSGENCODE_H */