contrib/ldns/higher.c

   1 /*
   2  * higher.c
   3  *
   4  * Specify some higher level functions that would
   5  * be usefull to would be developers
   6  *
   7  * a Net::DNS like library for C
   8  *
   9  * (c) NLnet Labs, 2004-2006
  10  *
  11  * See the file LICENSE for the license
  12  */
  13
  14 #include <ldns/config.h>
  15
  16 #include <ldns/ldns.h>
  17
  18 #ifdef HAVE_SSL
  19 #include <openssl/ssl.h>
  20 #include <openssl/sha.h>
  21 #endif /* HAVE_SSL */
  22
  23 ldns_rr_list *
  24 ldns_get_rr_list_addr_by_name(ldns_resolver *res, ldns_rdf *name, ldns_rr_class c,
  25                 uint16_t flags)
  26 {
  27         ldns_pkt *pkt;
  28         ldns_rr_list *aaaa;
  29         ldns_rr_list *a;
  30         ldns_rr_list *result = NULL;
  31         ldns_rr_list *hostsfilenames;
  32         size_t i;
  33         uint8_t ip6;
  34
  35         a = NULL;
  36         aaaa = NULL;
  37         result = NULL;
  38
  39         if (!res) {
  40                 return NULL;
  41         }
  42         if (ldns_rdf_get_type(name) != LDNS_RDF_TYPE_DNAME) {
  43                 return NULL;
  44         }
  45
  46         ip6 = ldns_resolver_ip6(res); /* we use INET_ANY here, save
  47                                          what was there */
  48
  49         ldns_resolver_set_ip6(res, LDNS_RESOLV_INETANY);
  50
  51         hostsfilenames = ldns_get_rr_list_hosts_frm_file(NULL);
  52         for (i = 0; i < ldns_rr_list_rr_count(hostsfilenames); i++) {
  53                 if (ldns_rdf_compare(name,
  54                                         ldns_rr_owner(ldns_rr_list_rr(hostsfilenames,
  55                                                         i))) == 0) {
  56                         if (!result) {
  57                                 result = ldns_rr_list_new();
  58                         }
  59                         ldns_rr_list_push_rr(result,
  60                                         ldns_rr_clone(ldns_rr_list_rr(hostsfilenames, i)));
  61                 }
  62         }
  63         ldns_rr_list_deep_free(hostsfilenames);
  64
  65         if (result) {
  66                 return result;
  67         }
  68
  69         /* add the RD flags, because we want an answer */
  70         pkt = ldns_resolver_query(res, name, LDNS_RR_TYPE_AAAA, c, flags | LDNS_RD);
  71         if (pkt) {
  72                 /* extract the data we need */
  73                 aaaa = ldns_pkt_rr_list_by_type(pkt, LDNS_RR_TYPE_AAAA,
  74                         LDNS_SECTION_ANSWER);
  75                 ldns_pkt_free(pkt);
  76         }
  77
  78         pkt = ldns_resolver_query(res, name, LDNS_RR_TYPE_A, c, flags | LDNS_RD);
  79         if (pkt) {
  80                 /* extract the data we need */
  81                 a = ldns_pkt_rr_list_by_type(pkt, LDNS_RR_TYPE_A, LDNS_SECTION_ANSWER);
  82                 ldns_pkt_free(pkt);
  83         }
  84         ldns_resolver_set_ip6(res, ip6);
  85
  86         if (aaaa && a) {
  87                 result = ldns_rr_list_cat_clone(aaaa, a);
  88                 ldns_rr_list_deep_free(aaaa);
  89                 ldns_rr_list_deep_free(a);
  90                 return result;
  91         }
  92
  93         if (aaaa) {
  94                 result = ldns_rr_list_clone(aaaa);
  95         }
  96
  97         if (a) {
  98                 result = ldns_rr_list_clone(a);
  99         }
 100
 101         ldns_rr_list_deep_free(aaaa);
 102         ldns_rr_list_deep_free(a);
 103         return result;
 104 }
 105
 106 ldns_rr_list *
 107 ldns_get_rr_list_name_by_addr(ldns_resolver *res, ldns_rdf *addr, ldns_rr_class c,
 108                 uint16_t flags)
 109 {
 110         ldns_pkt *pkt;
 111         ldns_rr_list *names;
 112         ldns_rdf *name;
 113         size_t i;
 114
 115         i = 0;
 116         names = NULL;
 117
 118         if (!res || !addr) {
 119                 return NULL;
 120         }
 121
 122         if (ldns_rdf_get_type(addr) != LDNS_RDF_TYPE_A &&
 123                         ldns_rdf_get_type(addr) != LDNS_RDF_TYPE_AAAA) {
 124                 return NULL;
 125         }
 126
 127         name = ldns_rdf_address_reverse(addr);
 128
 129         /* add the RD flags, because we want an answer */
 130         pkt = ldns_resolver_query(res, name, LDNS_RR_TYPE_PTR, c, flags | LDNS_RD);
 131         if (pkt) {
 132                 /* extract the data we need */
 133                 names = ldns_pkt_rr_list_by_type(pkt,
 134                                 LDNS_RR_TYPE_PTR, LDNS_SECTION_ANSWER);
 135         }
 136         return names;
 137 }
 138
 139 /* read a line, put it in a buffer, parse the buffer */
 140 ldns_rr_list *
 141 ldns_get_rr_list_hosts_frm_fp(FILE *fp)
 142 {
 143         return ldns_get_rr_list_hosts_frm_fp_l(fp, NULL);
 144 }
 145
 146 ldns_rr_list *
 147 ldns_get_rr_list_hosts_frm_fp_l(FILE *fp, int *line_nr)
 148 {
 149         ssize_t i, j;
 150         size_t cnt;
 151         char *line;
 152         char *word;
 153         char *addr;
 154         char *rr_str;
 155         ldns_buffer *linebuf;
 156         ldns_rr *rr;
 157         ldns_rr_list *list;
 158         ldns_rdf *tmp;
 159         bool ip6;
 160         ldns_status parse_result;
 161
 162         line = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1);
 163         word = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1);
 164         addr = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1);
 165         rr_str = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1);
 166         ip6 = false;
 167         list = ldns_rr_list_new();
 168         rr = NULL;
 169
 170         for(i = ldns_fget_token_l(fp, line, "\n", 0, line_nr);
 171                         i > 0; i = ldns_fget_token_l(fp, line, "\n", 0, line_nr)) {
 172                 /* # is comment */
 173                 if (line[0] == '#') {
 174                         continue;
 175                 }
 176                 /* put it in a buffer for further processing */
 177                 linebuf = LDNS_MALLOC(ldns_buffer);
 178
 179                 ldns_buffer_new_frm_data(linebuf, line, (size_t) i);
 180                 for(cnt = 0, j = ldns_bget_token(linebuf, word, LDNS_PARSE_NO_NL, 0);
 181                                 j > 0;
 182                                 j = ldns_bget_token(linebuf, word, LDNS_PARSE_NO_NL, 0), cnt++) {
 183                         if (cnt == 0) {
 184                                 /* the address */
 185                                 if ((tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_AAAA,
 186                                                                 word))) {
 187                                         /* ip6 */
 188                                         ldns_rdf_deep_free(tmp);
 189                                         ip6 = true;
 190                                 } else {
 191                                         if ((tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_A,
 192                                                                         word))) {
 193                                                 /* ip4 */
 194                                                 ldns_rdf_deep_free(tmp);
 195                                                 ip6 = false;
 196                                         } else {
 197                                                 /* kaput */
 198                                                 break;
 199                                         }
 200                                 }
 201                                 strlcpy(addr, word, LDNS_MAX_LINELEN+1);
 202                         } else {
 203                                 /* la al la la */
 204                                 if (ip6) {
 205                                         snprintf(rr_str, LDNS_MAX_LINELEN,
 206                                                 "%s IN AAAA %s", word, addr);
 207                                 } else {
 208                                         snprintf(rr_str, LDNS_MAX_LINELEN,
 209                                                 "%s IN A %s", word, addr);
 210                                 }
 211                                 parse_result = ldns_rr_new_frm_str(&rr, rr_str, 0, NULL, NULL);
 212                                 if (parse_result == LDNS_STATUS_OK && ldns_rr_owner(rr) && ldns_rr_rd_count(rr) > 0) {
 213                                         ldns_rr_list_push_rr(list, ldns_rr_clone(rr));
 214                                 }
 215                                 ldns_rr_free(rr);
 216                         }
 217                 }
 218                 ldns_buffer_free(linebuf);
 219         }
 220         LDNS_FREE(line);
 221         LDNS_FREE(word);
 222         LDNS_FREE(addr);
 223         LDNS_FREE(rr_str);
 224         return list;
 225 }
 226
 227 ldns_rr_list *
 228 ldns_get_rr_list_hosts_frm_file(char *filename)
 229 {
 230         ldns_rr_list *names;
 231         FILE *fp;
 232
 233         if (!filename) {
 234                 fp = fopen(LDNS_RESOLV_HOSTS, "r");
 235
 236         } else {
 237                 fp = fopen(filename, "r");
 238         }
 239         if (!fp) {
 240                 return NULL;
 241         }
 242
 243         names = ldns_get_rr_list_hosts_frm_fp(fp);
 244         fclose(fp);
 245         return names;
 246 }
 247
 248 uint16_t
 249 ldns_getaddrinfo(ldns_resolver *res, ldns_rdf *node, ldns_rr_class c,
 250                 ldns_rr_list **ret)
 251 {
 252         ldns_rdf_type t;
 253         uint16_t names_found;
 254         ldns_resolver *r;
 255         ldns_status s;
 256
 257         t = ldns_rdf_get_type(node);
 258         names_found = 0;
 259         r = res;
 260
 261         if (res == NULL) {
 262                 /* prepare a new resolver, using /etc/resolv.conf as a guide  */
 263                 s = ldns_resolver_new_frm_file(&r, NULL);
 264                 if (s != LDNS_STATUS_OK) {
 265                         return 0;
 266                 }
 267         }
 268
 269         if (t == LDNS_RDF_TYPE_DNAME) {
 270                 /* we're asked to query for a name */
 271                 *ret = ldns_get_rr_list_addr_by_name(r, node, c, 0);
 272                 names_found = ldns_rr_list_rr_count(*ret);
 273         }
 274
 275         if (t == LDNS_RDF_TYPE_A || t == LDNS_RDF_TYPE_AAAA) {
 276                 /* an address */
 277                 *ret = ldns_get_rr_list_name_by_addr(r, node, c, 0);
 278                 names_found = ldns_rr_list_rr_count(*ret);
 279         }
 280
 281         if (res == NULL) {
 282                 ldns_resolver_deep_free(r);
 283         }
 284
 285         return names_found;
 286 }
 287
 288 bool
 289 ldns_nsec_type_check(ldns_rr *nsec, ldns_rr_type t)
 290 {
 291         /* does the nsec cover the t given? */
 292         /* copied from host2str.c line 465: ldns_rdf2buffer_str_nsec */
 293         uint8_t window_block_nr;
 294         uint8_t bitmap_length;
 295         uint16_t type;
 296         uint16_t pos = 0;
 297         uint16_t bit_pos;
 298         ldns_rdf *nsec_type_list = ldns_rr_rdf(nsec, 1);
 299         uint8_t *data = ldns_rdf_data(nsec_type_list);
 300
 301         while(pos < ldns_rdf_size(nsec_type_list)) {
 302                 window_block_nr = data[pos];
 303                 bitmap_length = data[pos + 1];
 304                 pos += 2;
 305
 306                 for (bit_pos = 0; bit_pos < (bitmap_length) * 8; bit_pos++) {
 307                         if (ldns_get_bit(&data[pos], bit_pos)) {
 308                                 type = 256 * (uint16_t) window_block_nr + bit_pos;
 309
 310                                 if ((ldns_rr_type)type == t) {
 311                                         /* we have a winner */
 312                                         return true;
 313                                 }
 314                         }
 315                 }
 316                 pos += (uint16_t) bitmap_length;
 317         }
 318         return false;
 319 }
 320
 321 void
 322 ldns_print_rr_rdf(FILE *fp, ldns_rr *r, int rdfnum, ...)
 323 {
 324         int16_t rdf;
 325         ldns_rdf *rd;
 326         va_list va_rdf;
 327         va_start(va_rdf, rdfnum);
 328
 329         for (rdf = (int16_t)rdfnum; rdf != -1; rdf = (int16_t)va_arg(va_rdf, int))
 330         {
 331                 rd = ldns_rr_rdf(r, rdf);
 332                 if (!rd) {
 333                         continue;
 334                 } else {
 335                         ldns_rdf_print(fp, rd);
 336                         fprintf(fp, " "); /* not sure if we want to do this */
 337                 }
 338         }
 339         va_end(va_rdf);
 340 }