+#include <netinet/in.h>
+
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "dns.h"
-flxDnsPacket* flx_dns_packet_new(void) {
+flxDnsPacket* flx_dns_packet_new(guint max_size) {
+ flxDnsPacket *p;
+
+ if (max_size <= 0)
+ max_size = FLX_DNS_PACKET_MAX_SIZE;
+ else if (max_size < FLX_DNS_PACKET_HEADER_SIZE)
+ max_size = FLX_DNS_PACKET_HEADER_SIZE;
+
+ p = g_malloc(sizeof(flxDnsPacket) + max_size);
+ p->size = p->rindex = FLX_DNS_PACKET_HEADER_SIZE;
+ p->max_size = max_size;
+
+ memset(FLX_DNS_PACKET_DATA(p), 0, p->size);
+ return p;
+}
+
+flxDnsPacket* flx_dns_packet_new_query(guint max_size) {
+ flxDnsPacket *p;
+
+ p = flx_dns_packet_new(max_size);
+ flx_dns_packet_set_field(p, DNS_FIELD_FLAGS, DNS_FLAGS(0, 0, 0, 0, 0, 0, 0, 0, 0, 0));
+ return p;
+}
+
+flxDnsPacket* flx_dns_packet_new_response(guint max_size) {
flxDnsPacket *p;
- p = g_new(flxDnsPacket, 1);
- p->size = p->rindex = 2*6;
- memset(p->data, 0, p->size);
+
+ p = flx_dns_packet_new(max_size);
+ flx_dns_packet_set_field(p, DNS_FIELD_FLAGS, DNS_FLAGS(1, 0, 0, 0, 0, 0, 0, 0, 0, 0));
return p;
}
void flx_dns_packet_set_field(flxDnsPacket *p, guint index, guint16 v) {
g_assert(p);
- g_assert(index < 2*6);
+ g_assert(index < FLX_DNS_PACKET_HEADER_SIZE);
- ((guint16*) p->data)[index] = g_htons(v);
+ ((guint16*) FLX_DNS_PACKET_DATA(p))[index] = g_htons(v);
}
guint16 flx_dns_packet_get_field(flxDnsPacket *p, guint index) {
g_assert(p);
- g_assert(index < 2*6);
+ g_assert(index < FLX_DNS_PACKET_HEADER_SIZE);
- return g_ntohs(((guint16*) p->data)[index]);
+ return g_ntohs(((guint16*) FLX_DNS_PACKET_DATA(p))[index]);
}
guint8* flx_dns_packet_append_name(flxDnsPacket *p, const gchar *name) {
guint8 *d, *f = NULL;
+ guint saved_size;
g_assert(p);
g_assert(name);
+ saved_size = p->size;
+
for (;;) {
guint n = strcspn(name, ".");
if (!n || n > 63)
- return NULL;
+ goto fail;
- d = flx_dns_packet_extend(p, n+1);
+ if (!(d = flx_dns_packet_extend(p, n+1)))
+ goto fail;
+
if (!f)
f = d;
d[0] = n;
break;
}
- d = flx_dns_packet_extend(p, 1);
+ if (!(d = flx_dns_packet_extend(p, 1)))
+ goto fail;
+
d[0] = 0;
return f;
+
+fail:
+ p->size = saved_size;
+ return NULL;
}
guint8* flx_dns_packet_append_uint16(flxDnsPacket *p, guint16 v) {
guint8 *d;
-
g_assert(p);
- d = flx_dns_packet_extend(p, sizeof(guint16));
- *((guint16*) d) = g_htons(v);
+ if (!(d = flx_dns_packet_extend(p, sizeof(guint16))))
+ return NULL;
+ *((guint16*) d) = g_htons(v);
return d;
}
guint8 *flx_dns_packet_append_uint32(flxDnsPacket *p, guint32 v) {
guint8 *d;
-
g_assert(p);
- d = flx_dns_packet_extend(p, sizeof(guint32));
+
+ if (!(d = flx_dns_packet_extend(p, sizeof(guint32))))
+ return NULL;
+
*((guint32*) d) = g_htonl(v);
return d;
g_assert(p);
g_assert(b);
g_assert(l);
-
- d = flx_dns_packet_extend(p, l);
- g_assert(d);
- memcpy(d, b, l);
+ if (!(d = flx_dns_packet_extend(p, l)))
+ return NULL;
+
+ memcpy(d, b, l);
return d;
}
+guint8* flx_dns_packet_append_string(flxDnsPacket *p, const gchar *s) {
+ guint8* d;
+ guint k;
+
+ g_assert(p);
+ g_assert(s);
+
+ if ((k = strlen(s)) >= 255)
+ k = 255;
+
+ if (!(d = flx_dns_packet_extend(p, k+1)))
+ return NULL;
+
+ *d = (guint8) k;
+ memcpy(d+1, s, k);
+
+ return d;
+}
guint8 *flx_dns_packet_extend(flxDnsPacket *p, guint l) {
guint8 *d;
g_assert(p);
- g_assert(p->size+l <= sizeof(p->data));
- d = p->data + p->size;
+ if (p->size+l > p->max_size)
+ return NULL;
+
+ d = FLX_DNS_PACKET_DATA(p) + p->size;
p->size += l;
return d;
if (!prev)
return flx_dns_packet_append_name(p, name);
- k = prev - p->data;
+ k = prev - FLX_DNS_PACKET_DATA(p);
if (k < 0 || k >= 0x4000 || (guint) k >= p->size)
return flx_dns_packet_append_name(p, name);
- d = (guint16*) flx_dns_packet_extend(p, sizeof(guint16));
- *d = g_htons((0xC000 | k));
+ if (!(d = (guint16*) flx_dns_packet_extend(p, sizeof(guint16))))
+ return NULL;
+ *d = g_htons((0xC000 | k));
return prev;
}
if (index+1 > p->size)
return -1;
- n = p->data[index];
+ n = FLX_DNS_PACKET_DATA(p)[index];
if (!n) {
index++;
} else
first_label = 0;
- memcpy(ret_name, p->data + index, n);
+ memcpy(ret_name, FLX_DNS_PACKET_DATA(p) + index, n);
index += n;
ret_name += n;
l -= n;
if (index+2 > p->size)
return -1;
- index = ((guint) (p->data[index] & ~0xC0)) << 8 | p->data[index+1];
+ index = ((guint) (FLX_DNS_PACKET_DATA(p)[index] & ~0xC0)) << 8 | FLX_DNS_PACKET_DATA(p)[index+1];
if (!compressed)
ret += 2;
if (p->rindex + sizeof(guint16) > p->size)
return -1;
- *ret_v = g_ntohs(*((guint16*) (p->data + p->rindex)));
+ *ret_v = g_ntohs(*((guint16*) (FLX_DNS_PACKET_DATA(p) + p->rindex)));
p->rindex += sizeof(guint16);
return 0;
if (p->rindex + sizeof(guint32) > p->size)
return -1;
- *ret_v = g_ntohl(*((guint32*) (p->data + p->rindex)));
+ *ret_v = g_ntohl(*((guint32*) (FLX_DNS_PACKET_DATA(p) + p->rindex)));
p->rindex += sizeof(guint32);
return 0;
if (p->rindex + l > p->size)
return -1;
- memcpy(ret_data, p->data + p->rindex, l);
+ memcpy(ret_data, FLX_DNS_PACKET_DATA(p) + p->rindex, l);
p->rindex += l;
return 0;
}
+gint flx_dns_packet_consume_string(flxDnsPacket *p, gchar *ret_string, guint l) {
+ guint k;
+
+ g_assert(p);
+ g_assert(ret_string);
+ g_assert(l > 0);
+
+ if (p->rindex >= p->size)
+ return -1;
+
+ k = FLX_DNS_PACKET_DATA(p)[p->rindex];
+
+ if (p->rindex+1+k > p->size)
+ return -1;
+
+ if (l > k+1)
+ l = k+1;
+
+ memcpy(ret_string, FLX_DNS_PACKET_DATA(p)+p->rindex+1, l-1);
+ ret_string[l-1] = 0;
+
+
+ p->rindex += 1+k;
+
+ return 0;
+
+}
+
gconstpointer flx_dns_packet_get_rptr(flxDnsPacket *p) {
g_assert(p);
- if (p->rindex >= p->size)
+ if (p->rindex > p->size)
return NULL;
- return p->data + p->rindex;
+ return FLX_DNS_PACKET_DATA(p) + p->rindex;
}
gint flx_dns_packet_skip(flxDnsPacket *p, guint length) {
}
flxRecord* flx_dns_packet_consume_record(flxDnsPacket *p, gboolean *ret_cache_flush) {
- gchar name[256];
+ gchar name[257], buf[257];
guint16 type, class;
guint32 ttl;
guint16 rdlength;
gconstpointer data;
+ flxRecord *r = NULL;
+ gconstpointer start;
g_assert(p);
g_assert(ret_cache_flush);
+ g_message("consume_record()");
+
if (flx_dns_packet_consume_name(p, name, sizeof(name)) < 0 ||
flx_dns_packet_consume_uint16(p, &type) < 0 ||
flx_dns_packet_consume_uint16(p, &class) < 0 ||
flx_dns_packet_consume_uint32(p, &ttl) < 0 ||
flx_dns_packet_consume_uint16(p, &rdlength) < 0 ||
- !(data = flx_dns_packet_get_rptr(p)) ||
- flx_dns_packet_skip(p, rdlength) < 0)
- return NULL;
+ p->rindex + rdlength > p->size)
+
+ goto fail;
+
+ g_message("name = %s, rdlength = %u", name, rdlength);
+
+ start = flx_dns_packet_get_rptr(p);
+
+ r = flx_record_new_full(name, class, type);
+
+ switch (type) {
+ case FLX_DNS_TYPE_PTR:
+ case FLX_DNS_TYPE_CNAME:
+
+ g_message("ptr");
+
+ if (flx_dns_packet_consume_name(p, buf, sizeof(buf)) < 0)
+ goto fail;
+
+ r->data.ptr.name = g_strdup(buf);
+ break;
+
+
+ case FLX_DNS_TYPE_SRV:
+
+ g_message("srv");
+
+ if (flx_dns_packet_consume_uint16(p, &r->data.srv.priority) < 0 ||
+ flx_dns_packet_consume_uint16(p, &r->data.srv.weight) < 0 ||
+ flx_dns_packet_consume_uint16(p, &r->data.srv.port) < 0 ||
+ flx_dns_packet_consume_name(p, buf, sizeof(buf)) < 0)
+ goto fail;
+
+ r->data.srv.name = g_strdup(buf);
+ break;
+
+ case FLX_DNS_TYPE_HINFO:
+
+ g_message("hinfo");
+ if (flx_dns_packet_consume_string(p, buf, sizeof(buf)) < 0)
+ goto fail;
+
+ r->data.hinfo.cpu = g_strdup(buf);
+
+ if (flx_dns_packet_consume_string(p, buf, sizeof(buf)) < 0)
+ goto fail;
+
+ r->data.hinfo.os = g_strdup(buf);
+ break;
+
+ case FLX_DNS_TYPE_TXT:
+
+ g_message("txt");
+
+ if (rdlength > 0) {
+ r->data.txt.string_list = flx_string_list_parse(flx_dns_packet_get_rptr(p), rdlength);
+
+ if (flx_dns_packet_skip(p, rdlength) < 0)
+ goto fail;
+ }
+
+ break;
+
+ case FLX_DNS_TYPE_A:
+
+ g_message("A");
+
+
+ g_message("%p", flx_dns_packet_get_rptr(p));
+
+ if (flx_dns_packet_consume_bytes(p, &r->data.a.address, sizeof(flxIPv4Address)) < 0)
+ goto fail;
+
+ g_message("%p", flx_dns_packet_get_rptr(p));
+
+ break;
+
+ case FLX_DNS_TYPE_AAAA:
+
+ g_message("aaaa");
+
+ if (flx_dns_packet_consume_bytes(p, &r->data.aaaa.address, sizeof(flxIPv6Address)) < 0)
+ goto fail;
+
+ break;
+
+ default:
+
+ g_message("generic");
+
+ if (rdlength > 0) {
+
+ r->data.generic.data = g_memdup(flx_dns_packet_get_rptr(p), rdlength);
+
+ if (flx_dns_packet_skip(p, rdlength) < 0)
+ goto fail;
+ }
+
+ break;
+ }
+
+ g_message("%i == %u ?", (guint8*) flx_dns_packet_get_rptr(p) - (guint8*) start, rdlength);
+
+ /* Check if we read enough data */
+ if ((guint8*) flx_dns_packet_get_rptr(p) - (guint8*) start != rdlength)
+ goto fail;
+
*ret_cache_flush = !!(class & MDNS_CACHE_FLUSH);
class &= ~ MDNS_CACHE_FLUSH;
- return flx_record_new_full(name, class, type, data, rdlength, ttl);
+ r->ttl = ttl;
+
+ return r;
+
+fail:
+ if (r)
+ flx_record_unref(r);
+
+ return NULL;
}
flxKey* flx_dns_packet_consume_key(flxDnsPacket *p) {
guint8* flx_dns_packet_append_key(flxDnsPacket *p, flxKey *k) {
guint8 *t;
+ guint size;
g_assert(p);
g_assert(k);
+ size = p->size;
+
if (!(t = flx_dns_packet_append_name(p, k->name)) ||
!flx_dns_packet_append_uint16(p, k->type) ||
- !flx_dns_packet_append_uint16(p, k->class))
+ !flx_dns_packet_append_uint16(p, k->class)) {
+ p->size = size;
return NULL;
+ }
return t;
}
guint8* flx_dns_packet_append_record(flxDnsPacket *p, flxRecord *r, gboolean cache_flush) {
- guint8 *t;
+ guint8 *t, *l, *start;
+ guint size;
g_assert(p);
g_assert(r);
+ size = p->size;
+
if (!(t = flx_dns_packet_append_name(p, r->key->name)) ||
!flx_dns_packet_append_uint16(p, r->key->type) ||
!flx_dns_packet_append_uint16(p, cache_flush ? (r->key->class | MDNS_CACHE_FLUSH) : (r->key->class &~ MDNS_CACHE_FLUSH)) ||
!flx_dns_packet_append_uint32(p, r->ttl) ||
- !flx_dns_packet_append_uint16(p, r->size) ||
- !flx_dns_packet_append_bytes(p, r->data, r->size))
- return NULL;
+ !(l = flx_dns_packet_append_uint16(p, 0)))
+ goto fail;
+
+ start = flx_dns_packet_extend(p, 0);
+ switch (r->key->type) {
+
+ case FLX_DNS_TYPE_PTR:
+ case FLX_DNS_TYPE_CNAME :
+
+ if (!(flx_dns_packet_append_name(p, r->data.ptr.name)))
+ goto fail;
+
+ break;
+
+ case FLX_DNS_TYPE_SRV:
+
+ if (!flx_dns_packet_append_uint16(p, r->data.srv.priority) ||
+ !flx_dns_packet_append_uint16(p, r->data.srv.weight) ||
+ !flx_dns_packet_append_uint16(p, r->data.srv.port) ||
+ !flx_dns_packet_append_name(p, r->data.srv.name))
+ goto fail;
+
+ break;
+
+ case FLX_DNS_TYPE_HINFO:
+ if (!flx_dns_packet_append_string(p, r->data.hinfo.cpu) ||
+ !flx_dns_packet_append_string(p, r->data.hinfo.os))
+ goto fail;
+
+ break;
+
+ case FLX_DNS_TYPE_TXT: {
+
+ guint8 *data;
+ guint size;
+
+ size = flx_string_list_serialize(r->data.txt.string_list, NULL, 0);
+
+ g_message("appending string: %u %p", size, r->data.txt.string_list);
+
+ if (!(data = flx_dns_packet_extend(p, size)))
+ goto fail;
+
+ flx_string_list_serialize(r->data.txt.string_list, data, size);
+ break;
+ }
+
+
+ case FLX_DNS_TYPE_A:
+
+ if (!flx_dns_packet_append_bytes(p, &r->data.a.address, sizeof(r->data.a.address)))
+ goto fail;
+
+ break;
+
+ case FLX_DNS_TYPE_AAAA:
+
+ if (!flx_dns_packet_append_bytes(p, &r->data.aaaa.address, sizeof(r->data.aaaa.address)))
+ goto fail;
+
+ break;
+
+ default:
+
+ if (r->data.generic.size &&
+ flx_dns_packet_append_bytes(p, r->data.generic.data, r->data.generic.size))
+ goto fail;
+
+ break;
+ }
+
+
+
+
+ size = flx_dns_packet_extend(p, 0) - start;
+ g_assert(size <= 0xFFFF);
+
+ g_message("appended %u", size);
+
+ * (guint16*) l = g_htons((guint16) size);
+
return t;
+
+
+fail:
+ p->size = size;
+ return NULL;
+}
+
+gboolean flx_dns_packet_is_empty(flxDnsPacket *p) {
+ g_assert(p);
+
+ return p->size <= FLX_DNS_PACKET_HEADER_SIZE;
}