| 1 | /* Copyright (C) 1997-2016 Free Software Foundation, Inc. |
| 2 | This file is part of the GNU C Library. |
| 3 | Contributed by Thorsten Kukuk <kukuk@suse.de>, 1997. |
| 4 | |
| 5 | The GNU C Library is free software; you can redistribute it and/or |
| 6 | modify it under the terms of the GNU Lesser General Public |
| 7 | License as published by the Free Software Foundation; either |
| 8 | version 2.1 of the License, or (at your option) any later version. |
| 9 | |
| 10 | The GNU C Library is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public |
| 16 | License along with the GNU C Library; if not, see |
| 17 | <http://www.gnu.org/licenses/>. */ |
| 18 | |
| 19 | #include <atomic.h> |
| 20 | #include <ctype.h> |
| 21 | #include <errno.h> |
| 22 | #include <inttypes.h> |
| 23 | #include <netdb.h> |
| 24 | #include <nss.h> |
| 25 | #include <string.h> |
| 26 | #include <netinet/ether.h> |
| 27 | #include <netinet/if_ether.h> |
| 28 | #include <rpcsvc/nis.h> |
| 29 | #include <libc-lock.h> |
| 30 | |
| 31 | #include "nss-nisplus.h" |
| 32 | |
| 33 | __libc_lock_define_initialized (static, lock) |
| 34 | |
| 35 | static nis_result *result; |
| 36 | static nis_name tablename_val; |
| 37 | static u_long tablename_len; |
| 38 | |
| 39 | |
| 40 | #define NISENTRYVAL(idx, col, res) \ |
| 41 | (NIS_RES_OBJECT (res)[idx].zo_data.objdata_u.en_data.en_cols.en_cols_val[col].ec_value.ec_value_val) |
| 42 | |
| 43 | #define NISENTRYLEN(idx, col, res) \ |
| 44 | (NIS_RES_OBJECT (res)[idx].zo_data.objdata_u.en_data.en_cols.en_cols_val[col].ec_value.ec_value_len) |
| 45 | |
| 46 | static int |
| 47 | _nss_nisplus_parse_etherent (nis_result *result, struct etherent *ether, |
| 48 | char *buffer, size_t buflen, int *errnop) |
| 49 | { |
| 50 | char *p = buffer; |
| 51 | size_t room_left = buflen; |
| 52 | |
| 53 | if (result == NULL) |
| 54 | return 0; |
| 55 | |
| 56 | if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS) |
| 57 | || NIS_RES_NUMOBJ (result) != 1 |
| 58 | || __type_of (NIS_RES_OBJECT (result)) != NIS_ENTRY_OBJ |
| 59 | || strcmp (NIS_RES_OBJECT (result)->EN_data.en_type, |
| 60 | "ethers_tbl" ) != 0 |
| 61 | || NIS_RES_OBJECT (result)->EN_data.en_cols.en_cols_len < 2) |
| 62 | return 0; |
| 63 | |
| 64 | /* Generate the ether entry format and use the normal parser */ |
| 65 | if (NISENTRYLEN (0, 0, result) + 1 > room_left) |
| 66 | { |
| 67 | *errnop = ERANGE; |
| 68 | return -1; |
| 69 | } |
| 70 | char *cp = __stpncpy (p, NISENTRYVAL (0, 0, result), |
| 71 | NISENTRYLEN (0, 0, result)); |
| 72 | *cp = '\0'; |
| 73 | room_left -= NISENTRYLEN (0, 0, result) + 1; |
| 74 | ether->e_name = p; |
| 75 | |
| 76 | struct ether_addr *ea = ether_aton (NISENTRYVAL (0, 1, result)); |
| 77 | if (ea == NULL) |
| 78 | { |
| 79 | *errnop = EINVAL; |
| 80 | return -2; |
| 81 | } |
| 82 | |
| 83 | ether->e_addr = *ea; |
| 84 | |
| 85 | return 1; |
| 86 | } |
| 87 | |
| 88 | static enum nss_status |
| 89 | _nss_create_tablename (int *errnop) |
| 90 | { |
| 91 | if (tablename_val == NULL) |
| 92 | { |
| 93 | const char *local_dir = nis_local_directory (); |
| 94 | size_t local_dir_len = strlen (local_dir); |
| 95 | static const char prefix[] = "ethers.org_dir." ; |
| 96 | |
| 97 | char *p = malloc (sizeof (prefix) + local_dir_len); |
| 98 | if (p == NULL) |
| 99 | { |
| 100 | *errnop = errno; |
| 101 | return NSS_STATUS_TRYAGAIN; |
| 102 | } |
| 103 | |
| 104 | memcpy (__stpcpy (p, prefix), local_dir, local_dir_len + 1); |
| 105 | |
| 106 | tablename_len = sizeof (prefix) - 1 + local_dir_len; |
| 107 | |
| 108 | atomic_write_barrier (); |
| 109 | |
| 110 | tablename_val = p; |
| 111 | } |
| 112 | return NSS_STATUS_SUCCESS; |
| 113 | } |
| 114 | |
| 115 | |
| 116 | enum nss_status |
| 117 | _nss_nisplus_setetherent (int stayopen) |
| 118 | { |
| 119 | enum nss_status status; |
| 120 | int err; |
| 121 | |
| 122 | status = NSS_STATUS_SUCCESS; |
| 123 | |
| 124 | __libc_lock_lock (lock); |
| 125 | |
| 126 | if (result != NULL) |
| 127 | { |
| 128 | nis_freeresult (result); |
| 129 | result = NULL; |
| 130 | } |
| 131 | |
| 132 | if (_nss_create_tablename (&err) != NSS_STATUS_SUCCESS) |
| 133 | status = NSS_STATUS_UNAVAIL; |
| 134 | |
| 135 | __libc_lock_unlock (lock); |
| 136 | |
| 137 | return status; |
| 138 | } |
| 139 | |
| 140 | enum nss_status |
| 141 | _nss_nisplus_endetherent (void) |
| 142 | { |
| 143 | __libc_lock_lock (lock); |
| 144 | |
| 145 | if (result != NULL) |
| 146 | { |
| 147 | nis_freeresult (result); |
| 148 | result = NULL; |
| 149 | } |
| 150 | |
| 151 | __libc_lock_unlock (lock); |
| 152 | |
| 153 | return NSS_STATUS_SUCCESS; |
| 154 | } |
| 155 | |
| 156 | static enum nss_status |
| 157 | internal_nisplus_getetherent_r (struct etherent *ether, char *buffer, |
| 158 | size_t buflen, int *errnop) |
| 159 | { |
| 160 | if (tablename_val == NULL) |
| 161 | { |
| 162 | enum nss_status status = _nss_create_tablename (errnop); |
| 163 | |
| 164 | if (status != NSS_STATUS_SUCCESS) |
| 165 | return status; |
| 166 | } |
| 167 | |
| 168 | /* Get the next entry until we found a correct one. */ |
| 169 | int parse_res; |
| 170 | do |
| 171 | { |
| 172 | nis_result *saved_result; |
| 173 | |
| 174 | if (result == NULL) |
| 175 | { |
| 176 | saved_result = NULL; |
| 177 | result = nis_first_entry (tablename_val); |
| 178 | if (result == NULL) |
| 179 | { |
| 180 | *errnop = errno; |
| 181 | return NSS_STATUS_TRYAGAIN; |
| 182 | } |
| 183 | if (niserr2nss (result->status) != NSS_STATUS_SUCCESS) |
| 184 | return niserr2nss (result->status); |
| 185 | } |
| 186 | else |
| 187 | { |
| 188 | saved_result = result; |
| 189 | result = nis_next_entry (tablename_val, &result->cookie); |
| 190 | if (result == NULL) |
| 191 | { |
| 192 | *errnop = errno; |
| 193 | return NSS_STATUS_TRYAGAIN; |
| 194 | } |
| 195 | if (niserr2nss (result->status) != NSS_STATUS_SUCCESS) |
| 196 | { |
| 197 | nis_freeresult (saved_result); |
| 198 | return niserr2nss (result->status); |
| 199 | } |
| 200 | } |
| 201 | |
| 202 | parse_res = _nss_nisplus_parse_etherent (result, ether, buffer, |
| 203 | buflen, errnop); |
| 204 | if (parse_res == -1) |
| 205 | { |
| 206 | nis_freeresult (result); |
| 207 | result = saved_result; |
| 208 | return NSS_STATUS_TRYAGAIN; |
| 209 | } |
| 210 | |
| 211 | if (saved_result != NULL) |
| 212 | nis_freeresult (saved_result); |
| 213 | |
| 214 | } |
| 215 | while (!parse_res); |
| 216 | |
| 217 | return NSS_STATUS_SUCCESS; |
| 218 | } |
| 219 | |
| 220 | enum nss_status |
| 221 | _nss_nisplus_getetherent_r (struct etherent *result, char *buffer, |
| 222 | size_t buflen, int *errnop) |
| 223 | { |
| 224 | int status; |
| 225 | |
| 226 | __libc_lock_lock (lock); |
| 227 | |
| 228 | status = internal_nisplus_getetherent_r (result, buffer, buflen, errnop); |
| 229 | |
| 230 | __libc_lock_unlock (lock); |
| 231 | |
| 232 | return status; |
| 233 | } |
| 234 | |
| 235 | enum nss_status |
| 236 | _nss_nisplus_gethostton_r (const char *name, struct etherent *eth, |
| 237 | char *buffer, size_t buflen, int *errnop) |
| 238 | { |
| 239 | if (tablename_val == NULL) |
| 240 | { |
| 241 | enum nss_status status = _nss_create_tablename (errnop); |
| 242 | |
| 243 | if (status != NSS_STATUS_SUCCESS) |
| 244 | return status; |
| 245 | } |
| 246 | |
| 247 | if (name == NULL) |
| 248 | { |
| 249 | *errnop = EINVAL; |
| 250 | return NSS_STATUS_UNAVAIL; |
| 251 | } |
| 252 | |
| 253 | char buf[strlen (name) + 9 + tablename_len]; |
| 254 | int olderr = errno; |
| 255 | |
| 256 | snprintf (buf, sizeof (buf), "[name=%s],%s" , name, tablename_val); |
| 257 | |
| 258 | nis_result *result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS | USE_DGRAM, |
| 259 | NULL, NULL); |
| 260 | |
| 261 | if (result == NULL) |
| 262 | { |
| 263 | *errnop = ENOMEM; |
| 264 | return NSS_STATUS_TRYAGAIN; |
| 265 | } |
| 266 | |
| 267 | if (__glibc_unlikely (niserr2nss (result->status) != NSS_STATUS_SUCCESS)) |
| 268 | { |
| 269 | enum nss_status status = niserr2nss (result->status); |
| 270 | nis_freeresult (result); |
| 271 | return status; |
| 272 | } |
| 273 | |
| 274 | int parse_res = _nss_nisplus_parse_etherent (result, eth, buffer, |
| 275 | buflen, errnop); |
| 276 | |
| 277 | /* We do not need the lookup result anymore. */ |
| 278 | nis_freeresult (result); |
| 279 | |
| 280 | if (__glibc_unlikely (parse_res < 1)) |
| 281 | { |
| 282 | __set_errno (olderr); |
| 283 | |
| 284 | if (parse_res == -1) |
| 285 | return NSS_STATUS_TRYAGAIN; |
| 286 | |
| 287 | return NSS_STATUS_NOTFOUND; |
| 288 | } |
| 289 | |
| 290 | return NSS_STATUS_SUCCESS; |
| 291 | } |
| 292 | |
| 293 | enum nss_status |
| 294 | _nss_nisplus_getntohost_r (const struct ether_addr *addr, struct etherent *eth, |
| 295 | char *buffer, size_t buflen, int *errnop) |
| 296 | { |
| 297 | if (tablename_val == NULL) |
| 298 | { |
| 299 | __libc_lock_lock (lock); |
| 300 | |
| 301 | enum nss_status status = _nss_create_tablename (errnop); |
| 302 | |
| 303 | __libc_lock_unlock (lock); |
| 304 | |
| 305 | if (status != NSS_STATUS_SUCCESS) |
| 306 | return status; |
| 307 | } |
| 308 | |
| 309 | if (addr == NULL) |
| 310 | { |
| 311 | *errnop = EINVAL; |
| 312 | return NSS_STATUS_UNAVAIL; |
| 313 | } |
| 314 | |
| 315 | char buf[26 + tablename_len]; |
| 316 | |
| 317 | snprintf (buf, sizeof (buf), |
| 318 | "[addr=%" PRIx8 ":%" PRIx8 ":%" PRIx8 ":%" PRIx8 ":%" PRIx8 |
| 319 | ":%" PRIx8 "],%s" , |
| 320 | addr->ether_addr_octet[0], addr->ether_addr_octet[1], |
| 321 | addr->ether_addr_octet[2], addr->ether_addr_octet[3], |
| 322 | addr->ether_addr_octet[4], addr->ether_addr_octet[5], |
| 323 | tablename_val); |
| 324 | |
| 325 | nis_result *result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS | USE_DGRAM, |
| 326 | NULL, NULL); |
| 327 | |
| 328 | if (result == NULL) |
| 329 | { |
| 330 | *errnop = ENOMEM; |
| 331 | return NSS_STATUS_TRYAGAIN; |
| 332 | } |
| 333 | |
| 334 | if (__glibc_unlikely (niserr2nss (result->status) != NSS_STATUS_SUCCESS)) |
| 335 | { |
| 336 | enum nss_status status = niserr2nss (result->status); |
| 337 | nis_freeresult (result); |
| 338 | return status; |
| 339 | } |
| 340 | |
| 341 | int parse_res = _nss_nisplus_parse_etherent (result, eth, buffer, |
| 342 | buflen, errnop); |
| 343 | |
| 344 | /* We do not need the lookup result anymore. */ |
| 345 | nis_freeresult (result); |
| 346 | |
| 347 | if (__glibc_unlikely (parse_res < 1)) |
| 348 | { |
| 349 | if (parse_res == -1) |
| 350 | return NSS_STATUS_TRYAGAIN; |
| 351 | |
| 352 | return NSS_STATUS_NOTFOUND; |
| 353 | } |
| 354 | |
| 355 | return NSS_STATUS_SUCCESS; |
| 356 | } |
| 357 | |