chiark / gitweb /
resolved: handle IDNA domains
[elogind.git] / src / resolve / resolved-dns-packet.c
index 5eaee2cb4f751e2be52a1475deb869366f3d6ad1..ba056f1f444441000c65a77d3c9bc217bfbcdb52 100644 (file)
@@ -21,6 +21,7 @@
 
 #include "utf8.h"
 #include "util.h"
+#include "strv.h"
 #include "resolved-dns-domain.h"
 #include "resolved-dns-packet.h"
 
@@ -389,6 +390,7 @@ int dns_packet_append_name(DnsPacket *p, const char *name, size_t *start) {
                 _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) {
@@ -413,6 +415,17 @@ int dns_packet_append_name(DnsPacket *p, const char *name, size_t *start) {
                 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;
@@ -496,11 +509,28 @@ int dns_packet_append_rr(DnsPacket *p, const DnsResourceRecord *rr, size_t *star
         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;
 
@@ -512,6 +542,20 @@ int dns_packet_append_rr(DnsPacket *p, const DnsResourceRecord *rr, size_t *star
                 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;
@@ -549,11 +593,55 @@ int dns_packet_append_rr(DnsPacket *p, const DnsResourceRecord *rr, size_t *star
                 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;
         }
@@ -574,6 +662,9 @@ int dns_packet_append_rr(DnsPacket *p, const DnsResourceRecord *rr, size_t *star
                 goto fail;
         p->size = end;
 
+        if (start)
+                *start = saved_size;
+
         return 0;
 
 fail:
@@ -761,7 +852,7 @@ int dns_packet_read_name(DnsPacket *p, char **_ret, size_t *start) {
                         else
                                 first = false;
 
-                        memcpy(ret + n, t, c);
+                        memcpy(ret + n, t, r);
                         n += r;
                         continue;
                 } else if ((c & 0xc0) == 0xc0) {
@@ -851,6 +942,12 @@ fail:
         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;
@@ -868,6 +965,12 @@ int dns_packet_read_rr(DnsPacket *p, DnsResourceRecord **ret, size_t *start) {
         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;
@@ -891,9 +994,23 @@ int dns_packet_read_rr(DnsPacket *p, DnsResourceRecord **ret, size_t *start) {
 
         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;
 
@@ -905,6 +1022,24 @@ int dns_packet_read_rr(DnsPacket *p, DnsResourceRecord **ret, size_t *start) {
                 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;
@@ -942,11 +1077,96 @@ int dns_packet_read_rr(DnsPacket *p, DnsResourceRecord **ret, size_t *start) {
                 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;