#include "utf8.h"
#include "util.h"
+#include "strv.h"
#include "resolved-dns-domain.h"
#include "resolved-dns-packet.h"
h = DNS_PACKET_HEADER(p);
- if (protocol == DNS_PROTOCOL_DNS)
- h->flags = htobe16(DNS_PACKET_MAKE_FLAGS(0, 0, 0, 0, 1, 0, 0, 0, 0)); /* ask for recursion */
+ if (protocol == DNS_PROTOCOL_LLMNR)
+ h->flags = htobe16(DNS_PACKET_MAKE_FLAGS(0 /* qr */,
+ 0 /* opcode */,
+ 0 /* c */,
+ 0 /* tc */,
+ 0 /* t */,
+ 0 /* ra */,
+ 0 /* ad */,
+ 0 /* cd */,
+ 0 /* rcode */));
else
- h->flags = htobe16(DNS_PACKET_MAKE_FLAGS(0, 0, 0, 0, 0, 0, 0, 0, 0));
+ h->flags = htobe16(DNS_PACKET_MAKE_FLAGS(0 /* qr */,
+ 0 /* opcode */,
+ 0 /* aa */,
+ 0 /* tc */,
+ 1 /* rd (ask for recursion) */,
+ 0 /* ra */,
+ 0 /* ad */,
+ 0 /* cd */,
+ 0 /* rcode */));
*ret = p;
return 0;
if (DNS_PACKET_OPCODE(p) != 0)
return -EBADMSG;
+ /* RFC 4795, Section 2.1.1. says to discard all replies with QDCOUNT != 1 */
+ if (p->protocol == DNS_PROTOCOL_LLMNR &&
+ DNS_PACKET_QDCOUNT(p) != 1)
+ return -EBADMSG;
+
return 1;
}
if (DNS_PACKET_TC(p))
return -EBADMSG;
+ /* RFC 4795, Section 2.1.1. says to discard all queries with QDCOUNT != 1 */
if (p->protocol == DNS_PROTOCOL_LLMNR &&
DNS_PACKET_QDCOUNT(p) != 1)
return -EBADMSG;
+ /* RFC 4795, Section 2.1.1. says to discard all queries with ANCOUNT != 0 */
if (DNS_PACKET_ANCOUNT(p) > 0)
return -EBADMSG;
+ /* RFC 4795, Section 2.1.1. says to discard all queries with NSCOUNT != 0 */
if (DNS_PACKET_NSCOUNT(p) > 0)
return -EBADMSG;
_cleanup_free_ char *s = NULL;
char label[DNS_LABEL_MAX];
size_t n;
+ int k;
n = PTR_TO_SIZE(hashmap_get(p->names, name));
if (n > 0) {
if (r < 0)
goto fail;
+ if (p->protocol == DNS_PROTOCOL_DNS)
+ k = dns_label_apply_idna(label, r, label, sizeof(label));
+ else
+ k = dns_label_undo_idna(label, r, label, sizeof(label));
+ if (k < 0) {
+ r = k;
+ goto fail;
+ }
+ if (k > 0)
+ r = k;
+
r = dns_packet_append_label(p, label, r, &n);
if (r < 0)
goto fail;
if (r < 0)
goto fail;
- switch (rr->key->type) {
+ switch (rr->unparseable ? _DNS_TYPE_INVALID : rr->key->type) {
+
+ case DNS_TYPE_SRV:
+ r = dns_packet_append_uint16(p, rr->srv.priority, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint16(p, rr->srv.weight, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint16(p, rr->srv.port, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_name(p, rr->srv.name, NULL);
+ break;
case DNS_TYPE_PTR:
case DNS_TYPE_NS:
case DNS_TYPE_CNAME:
+ case DNS_TYPE_DNAME:
r = dns_packet_append_name(p, rr->ptr.name, NULL);
break;
r = dns_packet_append_string(p, rr->hinfo.os, NULL);
break;
+ case DNS_TYPE_SPF: /* exactly the same as TXT */
+ case DNS_TYPE_TXT: {
+ char **s;
+
+ STRV_FOREACH(s, rr->txt.strings) {
+ r = dns_packet_append_string(p, *s, NULL);
+ if (r < 0)
+ goto fail;
+ }
+
+ r = 0;
+ break;
+ }
+
case DNS_TYPE_A:
r = dns_packet_append_blob(p, &rr->a.in_addr, sizeof(struct in_addr), NULL);
break;
break;
case DNS_TYPE_MX:
- case DNS_TYPE_TXT:
- case DNS_TYPE_SRV:
- case DNS_TYPE_DNAME:
+ r = dns_packet_append_uint16(p, rr->mx.priority, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_name(p, rr->mx.exchange, NULL);
+ break;
+
+ case DNS_TYPE_LOC:
+ r = dns_packet_append_uint8(p, rr->loc.version, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint8(p, rr->loc.size, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint8(p, rr->loc.horiz_pre, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint8(p, rr->loc.vert_pre, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->loc.latitude, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->loc.longitude, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->loc.altitude, NULL);
+ break;
+
case DNS_TYPE_SSHFP:
+ r = dns_packet_append_uint8(p, rr->sshfp.algorithm, NULL);
+ if (r < 0)
+ goto fail;
+ r = dns_packet_append_uint8(p, rr->sshfp.fptype, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_blob(p, rr->sshfp.key, rr->sshfp.key_size, NULL);
+ break;
+
+ case _DNS_TYPE_INVALID: /* unparseable */
default:
+
r = dns_packet_append_blob(p, rr->generic.data, rr->generic.size, NULL);
break;
}
goto fail;
p->size = end;
+ if (start)
+ *start = saved_size;
+
return 0;
fail:
else
first = false;
- memcpy(ret + n, t, c);
+ memcpy(ret + n, t, r);
n += r;
continue;
} else if ((c & 0xc0) == 0xc0) {
return r;
}
+static bool loc_size_ok(uint8_t size) {
+ uint8_t m = size >> 4, e = size & 0xF;
+
+ return m <= 9 && e <= 9 && (m > 0 || e == 0);
+}
+
int dns_packet_read_rr(DnsPacket *p, DnsResourceRecord **ret, size_t *start) {
_cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
_cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
if (r < 0)
goto fail;
+ if (key->class == DNS_CLASS_ANY ||
+ key->type == DNS_TYPE_ANY) {
+ r = -EBADMSG;
+ goto fail;
+ }
+
rr = dns_resource_record_new(key);
if (!rr) {
r = -ENOMEM;
switch (rr->key->type) {
+ case DNS_TYPE_SRV:
+ r = dns_packet_read_uint16(p, &rr->srv.priority, NULL);
+ if (r < 0)
+ goto fail;
+ r = dns_packet_read_uint16(p, &rr->srv.weight, NULL);
+ if (r < 0)
+ goto fail;
+ r = dns_packet_read_uint16(p, &rr->srv.port, NULL);
+ if (r < 0)
+ goto fail;
+ r = dns_packet_read_name(p, &rr->srv.name, NULL);
+ break;
+
case DNS_TYPE_PTR:
case DNS_TYPE_NS:
case DNS_TYPE_CNAME:
+ case DNS_TYPE_DNAME:
r = dns_packet_read_name(p, &rr->ptr.name, NULL);
break;
r = dns_packet_read_string(p, &rr->hinfo.os, NULL);
break;
+ case DNS_TYPE_SPF: /* exactly the same as TXT */
+ case DNS_TYPE_TXT: {
+ char *s;
+
+ while (p->rindex < offset + rdlength) {
+ r = dns_packet_read_string(p, &s, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = strv_consume(&rr->txt.strings, s);
+ if (r < 0)
+ goto fail;
+ }
+
+ r = 0;
+ break;
+ }
+
case DNS_TYPE_A:
r = dns_packet_read_blob(p, &rr->a.in_addr, sizeof(struct in_addr), NULL);
break;
break;
case DNS_TYPE_MX:
- case DNS_TYPE_TXT:
- case DNS_TYPE_SRV:
- case DNS_TYPE_DNAME:
+ r = dns_packet_read_uint16(p, &rr->mx.priority, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_read_name(p, &rr->mx.exchange, NULL);
+ break;
+
+ case DNS_TYPE_LOC: {
+ uint8_t t;
+ size_t pos;
+
+ r = dns_packet_read_uint8(p, &t, &pos);
+ if (r < 0)
+ goto fail;
+
+ if (t == 0) {
+ rr->loc.version = t;
+
+ r = dns_packet_read_uint8(p, &rr->loc.size, NULL);
+ if (r < 0)
+ goto fail;
+
+ if (!loc_size_ok(rr->loc.size)) {
+ r = -EBADMSG;
+ goto fail;
+ }
+
+ r = dns_packet_read_uint8(p, &rr->loc.horiz_pre, NULL);
+ if (r < 0)
+ goto fail;
+
+ if (!loc_size_ok(rr->loc.horiz_pre)) {
+ r = -EBADMSG;
+ goto fail;
+ }
+
+ r = dns_packet_read_uint8(p, &rr->loc.vert_pre, NULL);
+ if (r < 0)
+ goto fail;
+
+ if (!loc_size_ok(rr->loc.vert_pre)) {
+ r = -EBADMSG;
+ goto fail;
+ }
+
+ r = dns_packet_read_uint32(p, &rr->loc.latitude, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_read_uint32(p, &rr->loc.longitude, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_read_uint32(p, &rr->loc.altitude, NULL);
+ if (r < 0)
+ goto fail;
+
+ break;
+ } else {
+ dns_packet_rewind(p, pos);
+ rr->unparseable = true;
+ goto unparseable;
+ }
+ }
+
case DNS_TYPE_SSHFP:
+
+ r = dns_packet_read_uint8(p, &rr->sshfp.algorithm, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_read_uint8(p, &rr->sshfp.fptype, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_read(p, rdlength - 2, &d, NULL);
+ if (r < 0)
+ goto fail;
+
+ rr->sshfp.key = memdup(d, rdlength - 2);
+ if (!rr->sshfp.key) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ rr->sshfp.key_size = rdlength - 2;
+ break;
+
default:
+ unparseable:
r = dns_packet_read(p, rdlength, &d, NULL);
if (r < 0)
goto fail;