external/bsd/libbind/dist/irs/dns_gr.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
   5  * Copyright (c) 1996-1999 by Internet Software Consortium.
   6  *
   7  * Permission to use, copy, modify, and distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
  12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  13  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
  14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  17  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 #if defined(LIBC_SCCS) && !defined(lint)
  21 static const char rcsid[] = "Id: dns_gr.c,v 1.4 2005/04/27 04:56:21 sra Exp";
  22 #endif
  23
  24 /*! \file
  25  * \brief
  26  * dns_gr.c --- this file contains the functions for accessing
  27  *      group information from Hesiod.
  28  */
  29
  30 #include "port_before.h"
  31
  32 #ifndef WANT_IRS_GR
  33 static int __bind_irs_gr_unneeded;
  34 #else
  35
  36 #include <sys/param.h>
  37 #include <sys/types.h>
  38
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42 #include <errno.h>
  43 #include <unistd.h>
  44
  45 #include <sys/types.h>
  46 #include <netinet/in.h>
  47 #include <arpa/nameser.h>
  48 #include <resolv.h>
  49
  50 #include <isc/memcluster.h>
  51
  52 #include <irs.h>
  53
  54 #include "port_after.h"
  55
  56 #include "irs_p.h"
  57 #include "hesiod.h"
  58 #include "dns_p.h"
  59
  60 /* Types. */
  61
  62 struct pvt {
  63         /*
  64          * This is our private accessor data.  It has a shared hesiod context.
  65          */
  66         struct dns_p *  dns;
  67         /*
  68          * Need space to store the entries read from the group file.
  69          * The members list also needs space per member, and the
  70          * strings making up the user names must be allocated
  71          * somewhere.  Rather than doing lots of small allocations,
  72          * we keep one buffer and resize it as needed.
  73          */
  74         struct group    group;
  75         size_t          nmemb;          /*%< Malloc'd max index of gr_mem[]. */
  76         char *          membuf;
  77         size_t          membufsize;
  78 };
  79
  80 /* Forward. */
  81
  82 static struct group *   gr_next(struct irs_gr *);
  83 static struct group *   gr_byname(struct irs_gr *, const char *);
  84 static struct group *   gr_bygid(struct irs_gr *, gid_t);
  85 static void             gr_rewind(struct irs_gr *);
  86 static void             gr_close(struct irs_gr *);
  87 static int              gr_list(struct irs_gr *, const char *,
  88                                 gid_t, gid_t *, int *);
  89 static void             gr_minimize(struct irs_gr *);
  90 static struct __res_state * gr_res_get(struct irs_gr *);
  91 static void             gr_res_set(struct irs_gr *,
  92                                    struct __res_state *,
  93                                    void (*)(void *));
  94
  95 static struct group *   get_hes_group(struct irs_gr *this,
  96                                       const char *name,
  97                                       const char *type);
  98
  99 /* Public. */
 100
 101 struct irs_gr *
 102 irs_dns_gr(struct irs_acc *this) {
 103         struct dns_p *dns = (struct dns_p *)this->private;
 104         struct irs_gr *gr;
 105         struct pvt *pvt;
 106
 107         if (!dns || !dns->hes_ctx) {
 108                 errno = ENODEV;
 109                 return (NULL);
 110         }
 111         if (!(pvt = memget(sizeof *pvt))) {
 112                 errno = ENOMEM;
 113                 return (NULL);
 114         }
 115         memset(pvt, 0, sizeof *pvt);
 116         pvt->dns = dns;
 117         if (!(gr = memget(sizeof *gr))) {
 118                 memput(pvt, sizeof *pvt);
 119                 errno = ENOMEM;
 120                 return (NULL);
 121         }
 122         memset(gr, 0x5e, sizeof *gr);
 123         gr->private = pvt;
 124         gr->next = gr_next;
 125         gr->byname = gr_byname;
 126         gr->bygid = gr_bygid;
 127         gr->rewind = gr_rewind;
 128         gr->close = gr_close;
 129         gr->list = gr_list;
 130         gr->minimize = gr_minimize;
 131         gr->res_get = gr_res_get;
 132         gr->res_set = gr_res_set;
 133         return (gr);
 134 }
 135
 136 /* methods */
 137
 138 static void
 139 gr_close(struct irs_gr *this) {
 140         struct pvt *pvt = (struct pvt *)this->private;
 141
 142         if (pvt->group.gr_mem)
 143                 free(pvt->group.gr_mem);
 144         if (pvt->membuf)
 145                 free(pvt->membuf);
 146         memput(pvt, sizeof *pvt);
 147         memput(this, sizeof *this);
 148 }
 149
 150 static struct group *
 151 gr_next(struct irs_gr *this) {
 152
 153         UNUSED(this);
 154
 155         return (NULL);
 156 }
 157
 158 static struct group *
 159 gr_byname(struct irs_gr *this, const char *name) {
 160         return (get_hes_group(this, name, "group"));
 161 }
 162
 163 static struct group *
 164 gr_bygid(struct irs_gr *this, gid_t gid) {
 165         char name[32];
 166
 167         sprintf(name, "%ld", (long)gid);
 168         return (get_hes_group(this, name, "gid"));
 169 }
 170
 171 static void
 172 gr_rewind(struct irs_gr *this) {
 173
 174         UNUSED(this);
 175
 176         /* NOOP */
 177 }
 178
 179 static int
 180 gr_list(struct irs_gr *this, const char *name,
 181         gid_t basegid, gid_t *groups, int *ngroups)
 182 {
 183         UNUSED(this);
 184         UNUSED(name);
 185         UNUSED(basegid);
 186         UNUSED(groups);
 187
 188         *ngroups = 0;
 189         /* There's some way to do this in Hesiod. */
 190         return (-1);
 191 }
 192
 193 static void
 194 gr_minimize(struct irs_gr *this) {
 195
 196         UNUSED(this);
 197         /* NOOP */
 198 }
 199
 200 /* Private. */
 201
 202 static struct group *
 203 get_hes_group(struct irs_gr *this, const char *name, const char *type) {
 204         struct pvt *pvt = (struct pvt *)this->private;
 205         char **hes_list, *cp, **new;
 206         size_t num_members = 0;
 207         u_long t;
 208
 209         hes_list = hesiod_resolve(pvt->dns->hes_ctx, name, type);
 210         if (!hes_list)
 211                 return (NULL);
 212
 213         /*
 214          * Copy the returned hesiod string into storage space.
 215          */
 216         if (pvt->membuf)
 217                 free(pvt->membuf);
 218         pvt->membuf = strdup(*hes_list);
 219         hesiod_free_list(pvt->dns->hes_ctx, hes_list);
 220
 221         cp = pvt->membuf;
 222         pvt->group.gr_name = cp;
 223         if (!(cp = strchr(cp, ':')))
 224                 goto cleanup;
 225         *cp++ = '\0';
 226
 227         pvt->group.gr_passwd = cp;
 228         if (!(cp = strchr(cp, ':')))
 229                 goto cleanup;
 230         *cp++ = '\0';
 231
 232         errno = 0;
 233         t = strtoul(cp, NULL, 10);
 234         if (errno == ERANGE)
 235                 goto cleanup;
 236         pvt->group.gr_gid = (gid_t) t;
 237         if (!(cp = strchr(cp, ':')))
 238                 goto cleanup;
 239         cp++;
 240
 241         /*
 242          * Parse the members out.
 243          */
 244         while (*cp) {
 245                 if (num_members+1 >= pvt->nmemb || pvt->group.gr_mem == NULL) {
 246                         pvt->nmemb += 10;
 247                         new = realloc(pvt->group.gr_mem,
 248                                       pvt->nmemb * sizeof(char *));
 249                         if (new == NULL)
 250                                 goto cleanup;
 251                         pvt->group.gr_mem = new;
 252                 }
 253                 pvt->group.gr_mem[num_members++] = cp;
 254                 if (!(cp = strchr(cp, ',')))
 255                         break;
 256                 *cp++ = '\0';
 257         }
 258         if (!pvt->group.gr_mem) {
 259                 pvt->group.gr_mem = malloc(sizeof(char*));
 260                 if (!pvt->group.gr_mem)
 261                         goto cleanup;
 262         }
 263         pvt->group.gr_mem[num_members] = NULL;
 264
 265         return (&pvt->group);
 266
 267  cleanup:
 268         if (pvt->group.gr_mem) {
 269                 free(pvt->group.gr_mem);
 270                 pvt->group.gr_mem = NULL;
 271         }
 272         if (pvt->membuf) {
 273                 free(pvt->membuf);
 274                 pvt->membuf = NULL;
 275         }
 276         return (NULL);
 277 }
 278
 279 static struct __res_state *
 280 gr_res_get(struct irs_gr *this) {
 281         struct pvt *pvt = (struct pvt *)this->private;
 282         struct dns_p *dns = pvt->dns;
 283
 284         return (__hesiod_res_get(dns->hes_ctx));
 285 }
 286
 287 static void
 288 gr_res_set(struct irs_gr *this, struct __res_state * res,
 289            void (*free_res)(void *)) {
 290         struct pvt *pvt = (struct pvt *)this->private;
 291         struct dns_p *dns = pvt->dns;
 292
 293         __hesiod_res_set(dns->hes_ctx, res, free_res);
 294 }
 295
 296 #endif /* WANT_IRS_GR */