contrib/dhcp-3.0/minires/res_sendsigned.c

   1 /*
   2  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (c) 1995-2003 by Internet Software Consortium
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
  10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  11  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
  12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  15  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16  *
  17  *   Internet Systems Consortium, Inc.
  18  *   950 Charter Street
  19  *   Redwood City, CA 94063
  20  *   <info@isc.org>
  21  *   http://www.isc.org/
  22  */
  23
  24 #include <sys/types.h>
  25 #include <sys/param.h>
  26
  27 #include <netinet/in.h>
  28 #include <arpa/inet.h>
  29 #include <sys/socket.h>
  30
  31 #include <errno.h>
  32 #include <netdb.h>
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #include <string.h>
  36 #include <unistd.h>
  37
  38 #include "minires/minires.h"
  39 #include "arpa/nameser.h"
  40
  41 #include <isc-dhcp/dst.h>
  42
  43 /* res_nsendsigned */
  44 isc_result_t
  45 res_nsendsigned(res_state statp,
  46                 double *msg, unsigned msglen, ns_tsig_key *key,
  47                 double *answer, unsigned anslen, unsigned *anssize)
  48 {
  49         res_state nstatp;
  50         DST_KEY *dstkey;
  51         int usingTCP = 0;
  52         double *newmsg;
  53         unsigned newmsglen;
  54         unsigned bufsize, siglen;
  55         u_char sig[64];
  56         HEADER *hp;
  57         time_t tsig_time;
  58         unsigned ret;
  59         isc_result_t rcode;
  60
  61         dst_init();
  62
  63         nstatp = (res_state) malloc(sizeof(*statp));
  64         if (nstatp == NULL)
  65                 return ISC_R_NOMEMORY;
  66         memcpy(nstatp, statp, sizeof(*statp));
  67
  68         bufsize = msglen + 1024;
  69         newmsg = (double *) malloc(bufsize);
  70         if (newmsg == NULL)
  71                 return ISC_R_NOMEMORY;
  72         memcpy(newmsg, msg, msglen);
  73         newmsglen = msglen;
  74
  75         if (ns_samename(key->alg, NS_TSIG_ALG_HMAC_MD5) != 1)
  76                 dstkey = NULL;
  77         else
  78                 dstkey = dst_buffer_to_key(key->name, KEY_HMAC_MD5,
  79                                            NS_KEY_TYPE_AUTH_ONLY,
  80                                            NS_KEY_PROT_ANY,
  81                                            key->data, key->len);
  82         if (dstkey == NULL) {
  83                 free(nstatp);
  84                 free(newmsg);
  85                 return ISC_R_BADKEY;
  86         }
  87
  88         nstatp->nscount = 1;
  89         siglen = sizeof(sig);
  90         rcode = ns_sign((u_char *)newmsg, &newmsglen, bufsize,
  91                         NOERROR, dstkey, NULL, 0,
  92                         sig, &siglen, 0);
  93         if (rcode != ISC_R_SUCCESS) {
  94                 free (nstatp);
  95                 free (newmsg);
  96                 return rcode;
  97         }
  98
  99         if (newmsglen > PACKETSZ || (nstatp->options & RES_IGNTC))
 100                 usingTCP = 1;
 101         if (usingTCP == 0)
 102                 nstatp->options |= RES_IGNTC;
 103         else
 104                 nstatp->options |= RES_USEVC;
 105
 106 retry:
 107
 108         rcode = res_nsend(nstatp, newmsg, newmsglen, answer, anslen, &ret);
 109         if (rcode != ISC_R_SUCCESS) {
 110                 free (nstatp);
 111                 free (newmsg);
 112                 return rcode;
 113         }
 114
 115         anslen = ret;
 116         rcode = ns_verify((u_char *)answer, &anslen, dstkey, sig, siglen,
 117                           NULL, NULL, &tsig_time,
 118                           (nstatp->options & RES_KEEPTSIG) ? 1 : 0);
 119         if (rcode != ISC_R_SUCCESS) {
 120                 Dprint(nstatp->pfcode & RES_PRF_REPLY,
 121                        (stdout, ";; TSIG invalid (%s)\n", p_rcode(ret)));
 122                 free (nstatp);
 123                 free (newmsg);
 124                 return rcode;
 125         }
 126         Dprint(nstatp->pfcode & RES_PRF_REPLY, (stdout, ";; TSIG ok\n"));
 127
 128         hp = (HEADER *) answer;
 129         if (hp->tc && usingTCP == 0) {
 130                 nstatp->options &= ~RES_IGNTC;
 131                 usingTCP = 1;
 132                 goto retry;
 133         }
 134
 135         free (nstatp);
 136         free (newmsg);
 137         *anssize = anslen;
 138         return ISC_R_SUCCESS;
 139 }