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Diffstat (limited to 'src/resolve/resolved-dns-packet.c')
-rw-r--r--src/resolve/resolved-dns-packet.c178
1 files changed, 178 insertions, 0 deletions
diff --git a/src/resolve/resolved-dns-packet.c b/src/resolve/resolved-dns-packet.c
index 1ebebf8ea4..d2b3cb0eb1 100644
--- a/src/resolve/resolved-dns-packet.c
+++ b/src/resolve/resolved-dns-packet.c
@@ -502,6 +502,89 @@ fail:
return r;
}
+static int dns_packet_append_type_window(DnsPacket *p, uint8_t window, uint8_t length, uint8_t *types, size_t *start) {
+ size_t saved_size;
+ int r;
+
+ assert(p);
+ assert(types);
+
+ if (length == 0)
+ return 0;
+
+ saved_size = p->size;
+
+ r = dns_packet_append_uint8(p, window, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint8(p, length, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_blob(p, types, length, NULL);
+ if (r < 0)
+ goto fail;
+
+ if (start)
+ *start = saved_size;
+
+ return 0;
+fail:
+ dns_packet_truncate(p, saved_size);
+ return r;
+}
+
+static int dns_packet_append_types(DnsPacket *p, Bitmap *types, size_t *start) {
+ uint8_t window = 0;
+ uint8_t len = 0;
+ uint8_t bitmaps[32] = {};
+ unsigned n;
+ size_t saved_size;
+ int r;
+
+ assert(p);
+ assert(types);
+
+ saved_size = p->size;
+
+ BITMAP_FOREACH(n, types) {
+ uint8_t entry;
+
+ assert(n <= 0xffff);
+
+ if ((n << 8) != window) {
+ r = dns_packet_append_type_window(p, window, len, bitmaps, NULL);
+ if (r < 0)
+ goto fail;
+
+ if (len > 0) {
+ len = 0;
+ zero(bitmaps);
+ }
+ }
+
+ window = n << 8;
+ len ++;
+
+ entry = n & 255;
+
+ bitmaps[entry / 8] |= 1 << (7 - (entry % 8));
+ }
+
+ r = dns_packet_append_type_window(p, window, len, bitmaps, NULL);
+ if (r < 0)
+ goto fail;
+
+ if (start)
+ *start = saved_size;
+
+ return 0;
+fail:
+ dns_packet_truncate(p, saved_size);
+ return r;
+}
+
int dns_packet_append_rr(DnsPacket *p, const DnsResourceRecord *rr, size_t *start) {
size_t saved_size, rdlength_offset, end, rdlength;
int r;
@@ -732,6 +815,16 @@ int dns_packet_append_rr(DnsPacket *p, const DnsResourceRecord *rr, size_t *star
r = dns_packet_append_blob(p, rr->rrsig.signature, rr->rrsig.signature_size, NULL);
break;
+ case DNS_TYPE_NSEC:
+ r = dns_packet_append_name(p, rr->nsec.next_domain_name, false, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_types(p, rr->nsec.types, NULL);
+ if (r < 0)
+ goto fail;
+
+ break;
case _DNS_TYPE_INVALID: /* unparseable */
default:
@@ -996,6 +1089,79 @@ fail:
return r;
}
+static int dns_packet_read_type_window(DnsPacket *p, Bitmap **types, size_t *start) {
+ uint8_t window;
+ uint8_t length;
+ const uint8_t *bitmap;
+ unsigned i;
+ bool found = false;
+ size_t saved_rindex;
+ int r;
+
+ assert(p);
+ assert(types);
+
+ saved_rindex = p->rindex;
+
+ r = bitmap_ensure_allocated(types);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_read_uint8(p, &window, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_read_uint8(p, &length, NULL);
+ if (r < 0)
+ goto fail;
+
+ if (length == 0 || length > 32)
+ return -EBADMSG;
+
+ r = dns_packet_read(p, length, (const void **)&bitmap, NULL);
+ if (r < 0)
+ goto fail;
+
+ for (i = 0; i < length; i++) {
+ uint8_t bitmask = 1 << 7;
+ uint8_t bit = 0;
+
+ if (!bitmap[i]) {
+ found = false;
+ continue;
+ }
+
+ found = true;
+
+ while (bitmask) {
+ if (bitmap[i] & bitmask) {
+ uint16_t n;
+
+ /* XXX: ignore pseudo-types? see RFC4034 section 4.1.2 */
+ n = (uint16_t) window << 8 | (uint16_t) bit;
+
+ r = bitmap_set(*types, n);
+ if (r < 0)
+ goto fail;
+ }
+
+ bit ++;
+ bitmask >>= 1;
+ }
+ }
+
+ if (!found)
+ return -EBADMSG;
+
+ if (start)
+ *start = saved_rindex;
+
+ return 0;
+fail:
+ dns_packet_rewind(p, saved_rindex);
+ return r;
+}
+
int dns_packet_read_key(DnsPacket *p, DnsResourceKey **ret, size_t *start) {
_cleanup_free_ char *name = NULL;
uint16_t class, type;
@@ -1382,6 +1548,18 @@ int dns_packet_read_rr(DnsPacket *p, DnsResourceRecord **ret, size_t *start) {
NULL);
break;
+ case DNS_TYPE_NSEC:
+ r = dns_packet_read_name(p, &rr->nsec.next_domain_name, false, NULL);
+ if (r < 0)
+ goto fail;
+
+ while (p->rindex != offset + rdlength) {
+ r = dns_packet_read_type_window(p, &rr->nsec.types, NULL);
+ if (r < 0)
+ goto fail;
+ }
+
+ break;
default:
unparseable:
r = dns_packet_read(p, rdlength, &d, NULL);