#include "utf8.h"
#include "util.h"
+#include "strv.h"
#include "resolved-dns-domain.h"
#include "resolved-dns-packet.h"
-int dns_packet_new(DnsPacket **ret, size_t mtu) {
+int dns_packet_new(DnsPacket **ret, DnsProtocol protocol, size_t mtu) {
DnsPacket *p;
size_t a;
p->size = p->rindex = DNS_PACKET_HEADER_SIZE;
p->allocated = a;
+ p->protocol = protocol;
p->n_ref = 1;
*ret = p;
return 0;
}
-int dns_packet_new_query(DnsPacket **ret, size_t mtu) {
+int dns_packet_new_query(DnsPacket **ret, DnsProtocol protocol, size_t mtu) {
DnsPacket *p;
DnsPacketHeader *h;
int r;
assert(ret);
- r = dns_packet_new(&p, mtu);
+ r = dns_packet_new(&p, protocol, mtu);
if (r < 0)
return r;
h = DNS_PACKET_HEADER(p);
- h->flags = htobe16(DNS_PACKET_MAKE_FLAGS(0, 0, 0, 0, 1, 0, 0, 0, 0));
+
+ 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 /* qr */,
+ 0 /* opcode */,
+ 0 /* aa */,
+ 0 /* tc */,
+ 1 /* rd (ask for recursion) */,
+ 0 /* ra */,
+ 0 /* ad */,
+ 0 /* cd */,
+ 0 /* rcode */));
*ret = p;
return 0;
assert(p);
+ dns_question_unref(p->question);
+ dns_answer_unref(p->answer);
+
while ((s = hashmap_steal_first_key(p->names)))
free(s);
hashmap_free(p->names);
- free(p->data);
+ free(p->_data);
free(p);
}
if (p->size > DNS_PACKET_SIZE_MAX)
return -EBADMSG;
- return 0;
+ return 1;
}
int dns_packet_validate_reply(DnsPacket *p) {
if (r < 0)
return r;
- if (DNS_PACKET_QR(p) == 0)
+ if (DNS_PACKET_QR(p) != 1)
+ 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;
+}
+
+int dns_packet_validate_query(DnsPacket *p) {
+ int r;
+
+ assert(p);
+
+ r = dns_packet_validate(p);
+ if (r < 0)
+ return r;
+
+ if (DNS_PACKET_QR(p) != 0)
+ return 0;
+
if (DNS_PACKET_OPCODE(p) != 0)
return -EBADMSG;
- return 0;
+ 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;
+
+ return 1;
}
static int dns_packet_extend(DnsPacket *p, size_t add, void **ret, size_t *start) {
if (p->size + add > a)
return -EMSGSIZE;
- if (p->data) {
+ if (p->_data) {
void *d;
- d = realloc(p->data, a);
+ d = realloc(p->_data, a);
if (!d)
return -ENOMEM;
- p->data = d;
+ p->_data = d;
} else {
- p->data = malloc(a);
- if (!p->data)
+ p->_data = malloc(a);
+ if (!p->_data)
return -ENOMEM;
- memcpy(p->data, (uint8_t*) p + ALIGN(sizeof(DnsPacket)), p->size);
- memzero((uint8_t*) p->data + p->size, a - p->size);
+ memcpy(p->_data, (uint8_t*) p + ALIGN(sizeof(DnsPacket)), p->size);
+ memzero((uint8_t*) p->_data + p->size, a - p->size);
}
p->allocated = a;
p->size = sz;
}
+int dns_packet_append_blob(DnsPacket *p, const void *d, size_t l, size_t *start) {
+ void *q;
+ int r;
+
+ assert(p);
+
+ r = dns_packet_extend(p, l, &q, start);
+ if (r < 0)
+ return r;
+
+ memcpy(q, d, l);
+ return 0;
+}
+
int dns_packet_append_uint8(DnsPacket *p, uint8_t v, size_t *start) {
void *d;
int r;
return r;
((uint8_t*) d)[0] = (uint8_t) (v >> 8);
- ((uint8_t*) d)[1] = (uint8_t) (v & 255);
+ ((uint8_t*) d)[1] = (uint8_t) v;
+
+ return 0;
+}
+
+int dns_packet_append_uint32(DnsPacket *p, uint32_t v, size_t *start) {
+ void *d;
+ int r;
+
+ assert(p);
+
+ r = dns_packet_extend(p, sizeof(uint32_t), &d, start);
+ if (r < 0)
+ return r;
+
+ ((uint8_t*) d)[0] = (uint8_t) (v >> 24);
+ ((uint8_t*) d)[1] = (uint8_t) (v >> 16);
+ ((uint8_t*) d)[2] = (uint8_t) (v >> 8);
+ ((uint8_t*) d)[3] = (uint8_t) v;
return 0;
}
saved_size = p->size;
- r = dns_packet_append_name(p, k->name, NULL);
+ r = dns_packet_append_name(p, DNS_RESOURCE_KEY_NAME(k), NULL);
if (r < 0)
goto fail;
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;
+
+ assert(p);
+ assert(rr);
+
+ saved_size = p->size;
+
+ r = dns_packet_append_key(p, rr->key, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->ttl, NULL);
+ if (r < 0)
+ goto fail;
+
+ /* Initially we write 0 here */
+ r = dns_packet_append_uint16(p, 0, &rdlength_offset);
+ if (r < 0)
+ goto fail;
+
+ 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;
+
+ case DNS_TYPE_HINFO:
+ r = dns_packet_append_string(p, rr->hinfo.cpu, NULL);
+ if (r < 0)
+ goto fail;
+
+ 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;
+
+ case DNS_TYPE_AAAA:
+ r = dns_packet_append_blob(p, &rr->aaaa.in6_addr, sizeof(struct in6_addr), NULL);
+ break;
+
+ case DNS_TYPE_SOA:
+ r = dns_packet_append_name(p, rr->soa.mname, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_name(p, rr->soa.rname, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->soa.serial, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->soa.refresh, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->soa.retry, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->soa.expire, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint32(p, rr->soa.minimum, NULL);
+ break;
+
+ case DNS_TYPE_MX:
+ 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_uint16(p, rr->loc.latitude, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint16(p, rr->loc.longitude, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_append_uint16(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;
+ }
+ if (r < 0)
+ goto fail;
+
+ /* Let's calculate the actual data size and update the field */
+ rdlength = p->size - rdlength_offset - sizeof(uint16_t);
+ if (rdlength > 0xFFFF) {
+ r = ENOSPC;
+ goto fail;
+ }
+
+ end = p->size;
+ p->size = rdlength_offset;
+ r = dns_packet_append_uint16(p, rdlength, NULL);
+ if (r < 0)
+ goto fail;
+ p->size = end;
+
+ if (start)
+ *start = saved_size;
+
+ return 0;
+
+fail:
+ dns_packet_truncate(p, saved_size);
+ return r;
+}
+
+
int dns_packet_read(DnsPacket *p, size_t sz, const void **ret, size_t *start) {
assert(p);
return 0;
}
-static void dns_packet_rewind(DnsPacket *p, size_t idx) {
+void dns_packet_rewind(DnsPacket *p, size_t idx) {
assert(p);
assert(idx <= p->size);
assert(idx >= DNS_PACKET_HEADER_SIZE);
p->rindex = idx;
}
+int dns_packet_read_blob(DnsPacket *p, void *d, size_t sz, size_t *start) {
+ const void *q;
+ int r;
+
+ assert(p);
+ assert(d);
+
+ r = dns_packet_read(p, sz, &q, start);
+ if (r < 0)
+ return r;
+
+ memcpy(d, q, sz);
+ return 0;
+}
+
int dns_packet_read_uint8(DnsPacket *p, uint8_t *ret, size_t *start) {
const void *d;
int r;
else
first = false;
- memcpy(ret + n, t, c);
+ memcpy(ret + n, t, r);
n += r;
continue;
} else if ((c & 0xc0) == 0xc0) {
return r;
}
-int dns_packet_read_key(DnsPacket *p, DnsResourceKey *ret, size_t *start) {
- _cleanup_(dns_resource_key_free) DnsResourceKey k = {};
+int dns_packet_read_key(DnsPacket *p, DnsResourceKey **ret, size_t *start) {
+ _cleanup_free_ char *name = NULL;
+ uint16_t class, type;
+ DnsResourceKey *key;
size_t saved_rindex;
int r;
saved_rindex = p->rindex;
- r = dns_packet_read_name(p, &k.name, NULL);
+ r = dns_packet_read_name(p, &name, NULL);
if (r < 0)
goto fail;
- r = dns_packet_read_uint16(p, &k.type, NULL);
+ r = dns_packet_read_uint16(p, &type, NULL);
if (r < 0)
goto fail;
- r = dns_packet_read_uint16(p, &k.class, NULL);
+ r = dns_packet_read_uint16(p, &class, NULL);
if (r < 0)
goto fail;
- *ret = k;
- zero(k);
+ key = dns_resource_key_new_consume(class, type, name);
+ if (!key) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ name = NULL;
+ *ret = key;
if (start)
*start = saved_rindex;
}
int dns_packet_read_rr(DnsPacket *p, DnsResourceRecord **ret, size_t *start) {
- _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr;
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+ _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
size_t saved_rindex, offset;
uint16_t rdlength;
const void *d;
assert(p);
assert(ret);
- rr = dns_resource_record_new();
- if (!rr)
- return -ENOMEM;
-
saved_rindex = p->rindex;
- r = dns_packet_read_key(p, &rr->key, NULL);
+ r = dns_packet_read_key(p, &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;
+ goto fail;
+ }
+
r = dns_packet_read_uint32(p, &rr->ttl, NULL);
if (r < 0)
goto fail;
offset = p->rindex;
- switch (rr->key.type) {
+ 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(p, sizeof(struct in_addr), &d, NULL);
+ r = dns_packet_read_blob(p, &rr->a.in_addr, sizeof(struct in_addr), NULL);
+ break;
+
+ case DNS_TYPE_AAAA:
+ r = dns_packet_read_blob(p, &rr->aaaa.in6_addr, sizeof(struct in6_addr), NULL);
+ break;
+
+ case DNS_TYPE_SOA:
+ r = dns_packet_read_name(p, &rr->soa.mname, NULL);
if (r < 0)
goto fail;
- memcpy(&rr->a.in_addr, d, sizeof(struct in_addr));
+ r = dns_packet_read_name(p, &rr->soa.rname, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_read_uint32(p, &rr->soa.serial, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_read_uint32(p, &rr->soa.refresh, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_read_uint32(p, &rr->soa.retry, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_read_uint32(p, &rr->soa.expire, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_read_uint32(p, &rr->soa.minimum, NULL);
break;
- case DNS_TYPE_AAAA:
- r = dns_packet_read(p, sizeof(struct in6_addr), &d, NULL);
+ case DNS_TYPE_MX:
+ 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;
+
+ r = dns_packet_read_uint8(p, &rr->loc.horiz_pre, NULL);
+ if (r < 0)
+ goto fail;
+
+ r = dns_packet_read_uint8(p, &rr->loc.vert_pre, NULL);
+ if (r < 0)
+ 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;
+ /* fall through */
+ }
+ }
+
+ 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;
- memcpy(&rr->aaaa.in6_addr, d, sizeof(struct in6_addr));
+ rr->sshfp.key = memdup(d, rdlength - 2);
+ if (!rr->sshfp.key) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ rr->sshfp.key_size = rdlength - 2;
break;
default:
return r;
}
-int dns_packet_skip_question(DnsPacket *p) {
+int dns_packet_extract(DnsPacket *p) {
+ _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
+ _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL;
+ size_t saved_rindex;
+ unsigned n, i;
int r;
- unsigned i, n;
- assert(p);
+ saved_rindex = p->rindex;
+ dns_packet_rewind(p, DNS_PACKET_HEADER_SIZE);
n = DNS_PACKET_QDCOUNT(p);
- for (i = 0; i < n; i++) {
- _cleanup_(dns_resource_key_free) DnsResourceKey key = {};
+ if (n > 0) {
+ question = dns_question_new(n);
+ if (!question) {
+ r = -ENOMEM;
+ goto finish;
+ }
- r = dns_packet_read_key(p, &key, NULL);
- if (r < 0)
- return r;
+ for (i = 0; i < n; i++) {
+ _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
+
+ r = dns_packet_read_key(p, &key, NULL);
+ if (r < 0)
+ goto finish;
+
+ r = dns_question_add(question, key);
+ if (r < 0)
+ goto finish;
+ }
}
- return 0;
+ n = DNS_PACKET_RRCOUNT(p);
+ if (n > 0) {
+ answer = dns_answer_new(n);
+ if (!answer) {
+ r = -ENOMEM;
+ goto finish;
+ }
+
+ for (i = 0; i < n; i++) {
+ _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
+
+ r = dns_packet_read_rr(p, &rr, NULL);
+ if (r < 0)
+ goto finish;
+
+ r = dns_answer_add(answer, rr);
+ if (r < 0)
+ goto finish;
+ }
+ }
+
+ p->question = question;
+ question = NULL;
+
+ p->answer = answer;
+ answer = NULL;
+
+ r = 0;
+
+finish:
+ p->rindex = saved_rindex;
+ return r;
}
static const char* const dns_rcode_table[_DNS_RCODE_MAX_DEFINED] = {
[DNS_RCODE_BADTRUNC] = "BADTRUNC",
};
DEFINE_STRING_TABLE_LOOKUP(dns_rcode, int);
+
+static const char* const dns_protocol_table[_DNS_PROTOCOL_MAX] = {
+ [DNS_PROTOCOL_DNS] = "dns",
+ [DNS_PROTOCOL_MDNS] = "mdns",
+ [DNS_PROTOCOL_LLMNR] = "llmnr",
+};
+DEFINE_STRING_TABLE_LOOKUP(dns_protocol, DnsProtocol);
~ianmdlvl / elogind.git / blobdiff