-/* Copyright 1998 by the Massachusetts Institute of Technology.
+
+/* Copyright 1998, 2011 by the Massachusetts Institute of Technology.
*
* Permission to use, copy, modify, and distribute this
* software and its documentation for any purpose and without
* without express or implied warranty.
*/
-#include "setup.h"
-#include <sys/types.h>
+#include "ares_setup.h"
-#ifdef WIN32
-#include "nameser.h"
+#ifdef HAVE_NETINET_IN_H
+# include <netinet/in.h>
+#endif
+#ifdef HAVE_ARPA_NAMESER_H
+# include <arpa/nameser.h>
#else
-#include <netinet/in.h>
-#include <arpa/nameser.h>
+# include "nameser.h"
+#endif
+#ifdef HAVE_ARPA_NAMESER_COMPAT_H
+# include <arpa/nameser_compat.h>
#endif
-#include <stdlib.h>
#include "ares.h"
+#include "ares_nowarn.h"
#include "ares_private.h" /* for the memdebug */
static int name_length(const unsigned char *encoded, const unsigned char *abuf,
- int alen);
+ int alen);
/* Expand an RFC1035-encoded domain name given by encoded. The
* containing message is given by abuf and alen. The result given by
*/
int ares_expand_name(const unsigned char *encoded, const unsigned char *abuf,
- int alen, char **s, long *enclen)
+ int alen, char **s, long *enclen)
{
int len, indir = 0;
char *q;
const unsigned char *p;
+ union {
+ ssize_t sig;
+ size_t uns;
+ } nlen;
- len = name_length(encoded, abuf, alen);
- if (len == -1)
+ nlen.sig = name_length(encoded, abuf, alen);
+ if (nlen.sig < 0)
return ARES_EBADNAME;
- *s = malloc(len + 1);
+ *s = malloc(nlen.uns + 1);
if (!*s)
return ARES_ENOMEM;
q = *s;
+ if (nlen.uns == 0) {
+ /* RFC2181 says this should be ".": the root of the DNS tree.
+ * Since this function strips trailing dots though, it becomes ""
+ */
+ q[0] = '\0';
+
+ /* indirect root label (like 0xc0 0x0c) is 2 bytes long (stupid, but
+ valid) */
+ if ((*encoded & INDIR_MASK) == INDIR_MASK)
+ *enclen = 2L;
+ else
+ *enclen = 1L; /* the caller should move one byte to get past this */
+
+ return ARES_SUCCESS;
+ }
+
/* No error-checking necessary; it was all done by name_length(). */
p = encoded;
while (*p)
{
if ((*p & INDIR_MASK) == INDIR_MASK)
- {
- if (!indir)
- {
- *enclen = p + 2 - encoded;
- indir = 1;
- }
- p = abuf + ((*p & ~INDIR_MASK) << 8 | *(p + 1));
- }
+ {
+ if (!indir)
+ {
+ *enclen = aresx_uztosl(p + 2U - encoded);
+ indir = 1;
+ }
+ p = abuf + ((*p & ~INDIR_MASK) << 8 | *(p + 1));
+ }
else
- {
- len = *p;
- p++;
- while (len--)
- {
- if (*p == '.' || *p == '\\')
- *q++ = '\\';
- *q++ = *p;
- p++;
- }
- *q++ = '.';
- }
+ {
+ len = *p;
+ p++;
+ while (len--)
+ {
+ if (*p == '.' || *p == '\\')
+ *q++ = '\\';
+ *q++ = *p;
+ p++;
+ }
+ *q++ = '.';
+ }
}
if (!indir)
- *enclen = p + 1 - encoded;
+ *enclen = aresx_uztosl(p + 1U - encoded);
/* Nuke the trailing period if we wrote one. */
if (q > *s)
*(q - 1) = 0;
+ else
+ *q = 0; /* zero terminate */
return ARES_SUCCESS;
}
* -1 if the encoding is invalid.
*/
static int name_length(const unsigned char *encoded, const unsigned char *abuf,
- int alen)
+ int alen)
{
int n = 0, offset, indir = 0;
/* Allow the caller to pass us abuf + alen and have us check for it. */
- if (encoded == abuf + alen)
+ if (encoded >= abuf + alen)
return -1;
while (*encoded)
{
if ((*encoded & INDIR_MASK) == INDIR_MASK)
- {
- /* Check the offset and go there. */
- if (encoded + 1 >= abuf + alen)
- return -1;
- offset = (*encoded & ~INDIR_MASK) << 8 | *(encoded + 1);
- if (offset >= alen)
- return -1;
- encoded = abuf + offset;
-
- /* If we've seen more indirects than the message length,
- * then there's a loop.
- */
- if (++indir > alen)
- return -1;
- }
+ {
+ /* Check the offset and go there. */
+ if (encoded + 1 >= abuf + alen)
+ return -1;
+ offset = (*encoded & ~INDIR_MASK) << 8 | *(encoded + 1);
+ if (offset >= alen)
+ return -1;
+ encoded = abuf + offset;
+
+ /* If we've seen more indirects than the message length,
+ * then there's a loop.
+ */
+ if (++indir > alen)
+ return -1;
+ }
else
- {
- offset = *encoded;
- if (encoded + offset + 1 >= abuf + alen)
- return -1;
- encoded++;
- while (offset--)
- {
- n += (*encoded == '.' || *encoded == '\\') ? 2 : 1;
- encoded++;
- }
- n++;
- }
+ {
+ offset = *encoded;
+ if (encoded + offset + 1 >= abuf + alen)
+ return -1;
+ encoded++;
+ while (offset--)
+ {
+ n += (*encoded == '.' || *encoded == '\\') ? 2 : 1;
+ encoded++;
+ }
+ n++;
+ }
}
/* If there were any labels at all, then the number of dots is one
*/
return (n) ? n - 1 : n;
}
+
+/* Like ares_expand_name but returns EBADRESP in case of invalid input. */
+int ares__expand_name_for_response(const unsigned char *encoded,
+ const unsigned char *abuf, int alen,
+ char **s, long *enclen)
+{
+ int status = ares_expand_name(encoded, abuf, alen, s, enclen);
+ if (status == ARES_EBADNAME)
+ status = ARES_EBADRESP;
+ return status;
+}
projects / platform / upstream / c-ares.git / blobdiff