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authorhpopescu@ixiacom.com <hpopescu@ixiacom.com>2012-08-10 12:06:09 +0300
committerDaniel Stenberg <daniel@haxx.se>2012-08-17 00:54:47 +0200
commit90364defb038d5d6b97acf9df9ed152d2393a863 (patch)
tree82ea71d7a7718652727fed628849a247c464728b /ares_mkquery.c
parente447bc5c603a139852fd74d9930c1293535ea749 (diff)
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Added new feature (rfc2671)
Diffstat (limited to 'ares_mkquery.c')
-rw-r--r--ares_mkquery.c173
1 files changed, 1 insertions, 172 deletions
diff --git a/ares_mkquery.c b/ares_mkquery.c
index e33f13f..5aea914 100644
--- a/ares_mkquery.c
+++ b/ares_mkquery.c
@@ -15,181 +15,10 @@
*/
#include "ares_setup.h"
-
-#ifdef HAVE_SYS_SOCKET_H
-# include <sys/socket.h>
-#endif
-#ifdef HAVE_NETINET_IN_H
-# include <netinet/in.h>
-#endif
-#ifdef HAVE_ARPA_NAMESER_H
-# include <arpa/nameser.h>
-#else
-# include "nameser.h"
-#endif
-#ifdef HAVE_ARPA_NAMESER_COMPAT_H
-# include <arpa/nameser_compat.h>
-#endif
-
-#include <stdlib.h>
-#include <string.h>
#include "ares.h"
-#include "ares_dns.h"
-#include "ares_private.h"
-
-/* Header format, from RFC 1035:
- * 1 1 1 1 1 1
- * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
- * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- * | ID |
- * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- * |QR| Opcode |AA|TC|RD|RA| Z | RCODE |
- * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- * | QDCOUNT |
- * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- * | ANCOUNT |
- * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- * | NSCOUNT |
- * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- * | ARCOUNT |
- * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- *
- * AA, TC, RA, and RCODE are only set in responses. Brief description
- * of the remaining fields:
- * ID Identifier to match responses with queries
- * QR Query (0) or response (1)
- * Opcode For our purposes, always QUERY
- * RD Recursion desired
- * Z Reserved (zero)
- * QDCOUNT Number of queries
- * ANCOUNT Number of answers
- * NSCOUNT Number of name server records
- * ARCOUNT Number of additional records
- *
- * Question format, from RFC 1035:
- * 1 1 1 1 1 1
- * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
- * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- * | |
- * / QNAME /
- * / /
- * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- * | QTYPE |
- * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- * | QCLASS |
- * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
- *
- * The query name is encoded as a series of labels, each represented
- * as a one-byte length (maximum 63) followed by the text of the
- * label. The list is terminated by a label of length zero (which can
- * be thought of as the root domain).
- */
int ares_mkquery(const char *name, int dnsclass, int type, unsigned short id,
int rd, unsigned char **buf, int *buflen)
{
- int len;
- unsigned char *q;
- const char *p;
-
- /* Set our results early, in case we bail out early with an error. */
- *buflen = 0;
- *buf = NULL;
-
- /* Compute the length of the encoded name so we can check buflen.
- * Start counting at 1 for the zero-length label at the end. */
- len = 1;
- for (p = name; *p; p++)
- {
- if (*p == '\\' && *(p + 1) != 0)
- p++;
- len++;
- }
- /* If there are n periods in the name, there are n + 1 labels, and
- * thus n + 1 length fields, unless the name is empty or ends with a
- * period. So add 1 unless name is empty or ends with a period.
- */
- if (*name && *(p - 1) != '.')
- len++;
-
- /* Immediately reject names that are longer than the maximum of 255
- * bytes that's specified in RFC 1035 ("To simplify implementations,
- * the total length of a domain name (i.e., label octets and label
- * length octets) is restricted to 255 octets or less."). We aren't
- * doing this just to be a stickler about RFCs. For names that are
- * too long, 'dnscache' closes its TCP connection to us immediately
- * (when using TCP) and ignores the request when using UDP, and
- * BIND's named returns ServFail (TCP or UDP). Sending a request
- * that we know will cause 'dnscache' to close the TCP connection is
- * painful, since that makes any other outstanding requests on that
- * connection fail. And sending a UDP request that we know
- * 'dnscache' will ignore is bad because resources will be tied up
- * until we time-out the request.
- */
- if (len > MAXCDNAME)
- return ARES_EBADNAME;
-
- *buflen = len + HFIXEDSZ + QFIXEDSZ;
- *buf = malloc(*buflen);
- if (!*buf)
- return ARES_ENOMEM;
-
- /* Set up the header. */
- q = *buf;
- memset(q, 0, HFIXEDSZ);
- DNS_HEADER_SET_QID(q, id);
- DNS_HEADER_SET_OPCODE(q, QUERY);
- if (rd) {
- DNS_HEADER_SET_RD(q, 1);
- }
- else {
- DNS_HEADER_SET_RD(q, 0);
- }
- DNS_HEADER_SET_QDCOUNT(q, 1);
-
- /* A name of "." is a screw case for the loop below, so adjust it. */
- if (strcmp(name, ".") == 0)
- name++;
-
- /* Start writing out the name after the header. */
- q += HFIXEDSZ;
- while (*name)
- {
- if (*name == '.')
- return ARES_EBADNAME;
-
- /* Count the number of bytes in this label. */
- len = 0;
- for (p = name; *p && *p != '.'; p++)
- {
- if (*p == '\\' && *(p + 1) != 0)
- p++;
- len++;
- }
- if (len > MAXLABEL)
- return ARES_EBADNAME;
-
- /* Encode the length and copy the data. */
- *q++ = (unsigned char)len;
- for (p = name; *p && *p != '.'; p++)
- {
- if (*p == '\\' && *(p + 1) != 0)
- p++;
- *q++ = *p;
- }
-
- /* Go to the next label and repeat, unless we hit the end. */
- if (!*p)
- break;
- name = p + 1;
- }
-
- /* Add the zero-length label at the end. */
- *q++ = 0;
-
- /* Finish off the question with the type and class. */
- DNS_QUESTION_SET_TYPE(q, type);
- DNS_QUESTION_SET_CLASS(q, dnsclass);
-
- return ARES_SUCCESS;
+ return ares_create_query(name, dnsclass, type, id, rd, buf, buflen, 0);
}