ircd/privilege.c

   1 /*
   2  * Solanum: a slightly advanced ircd
   3  * privilege.c: Dynamic privileges API.
   4  *
   5  * Copyright (c) 2021 Ed Kellett <e@kellett.im>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
  20  * USA
  21  *
  22  * Copyright (c) 2008 William Pitcock <nenolod@dereferenced.org>
  23  *
  24  * Permission to use, copy, modify, and/or distribute this software for any
  25  * purpose with or without fee is hereby granted, provided that the above
  26  * copyright notice and this permission notice is present in all copies.
  27  *
  28  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  29  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  30  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  31  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
  32  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  33  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  34  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  36  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  37  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  38  * POSSIBILITY OF SUCH DAMAGE.
  39  */
  40
  41 #include <stdinc.h>
  42 #include "s_conf.h"
  43 #include "privilege.h"
  44 #include "numeric.h"
  45 #include "s_assert.h"
  46 #include "logger.h"
  47 #include "send.h"
  48
  49 static rb_dlink_list privilegeset_list = {NULL, NULL, 0};
  50
  51 static struct PrivilegeSet *
  52 privilegeset_get_any(const char *name)
  53 {
  54         rb_dlink_node *iter;
  55
  56         s_assert(name != NULL);
  57
  58         RB_DLINK_FOREACH(iter, privilegeset_list.head)
  59         {
  60                 struct PrivilegeSet *set = (struct PrivilegeSet *) iter->data;
  61
  62                 if (!rb_strcasecmp(set->name, name))
  63                         return set;
  64         }
  65
  66         return NULL;
  67 }
  68
  69 static int
  70 privilegeset_cmp_priv(const void *a_, const void *b_)
  71 {
  72         const char *const *a = a_, *const *b = b_;
  73         return strcmp(*a, *b);
  74 }
  75
  76 static void
  77 privilegeset_index(struct PrivilegeSet *set)
  78 {
  79         size_t n;
  80         const char *s;
  81         const char **p;
  82
  83         rb_free(set->privs);
  84
  85         set->privs = rb_malloc(sizeof *set->privs * (set->size + 1));
  86         p = set->privs;
  87
  88         for (n = 0, s = set->priv_storage; n < set->size; n++, s += strlen(s) + 1)
  89                 *p++ = s;
  90         qsort(set->privs, set->size, sizeof *set->privs, privilegeset_cmp_priv);
  91         set->privs[set->size] = NULL;
  92 }
  93
  94 static void
  95 privilegeset_add_privs(struct PrivilegeSet *dst, const char *privs)
  96 {
  97         size_t alloc_size;
  98         size_t n;
  99
 100         if (dst->priv_storage == NULL)
 101         {
 102                 dst->stored_size = dst->allocated_size = 0;
 103                 alloc_size = 256;
 104         }
 105         else
 106         {
 107                 alloc_size = dst->allocated_size;
 108         }
 109
 110         dst->stored_size += strlen(privs) + 1;
 111
 112         while (alloc_size < dst->stored_size)
 113                 alloc_size *= 2;
 114
 115         if (alloc_size > dst->allocated_size)
 116                 dst->priv_storage = rb_realloc(dst->priv_storage, alloc_size);
 117
 118         dst->allocated_size = alloc_size;
 119
 120         const char *s;
 121         char *d;
 122         for (s = privs, d = dst->priv_storage; s < privs + strlen(privs); s += n , d += n)
 123         {
 124                 const char *e = strchr(s, ' ');
 125                 /* up to space if there is one, else up to end of string */
 126                 n = 1 + (e != NULL ? e - s : strlen(s));
 127                 rb_strlcpy(d, s, n);
 128
 129                 dst->size += 1;
 130         }
 131
 132         privilegeset_index(dst);
 133 }
 134
 135 static void
 136 privilegeset_add_privilegeset(struct PrivilegeSet *dst, const struct PrivilegeSet *src)
 137 {
 138         size_t cur_size, alloc_size;
 139
 140         if (dst->priv_storage == NULL)
 141         {
 142                 dst->stored_size = dst->allocated_size = 0;
 143                 cur_size = 0;
 144                 alloc_size = 256;
 145         }
 146         else
 147         {
 148                 cur_size = dst->stored_size;
 149                 alloc_size = dst->allocated_size;
 150         }
 151
 152         dst->stored_size = cur_size + src->stored_size;
 153
 154         while (alloc_size < dst->stored_size)
 155                 alloc_size *= 2;
 156
 157         if (alloc_size > dst->allocated_size)
 158                 dst->priv_storage = rb_realloc(dst->priv_storage, alloc_size);
 159
 160         dst->allocated_size = alloc_size;
 161
 162         memcpy(dst->priv_storage + cur_size, src->priv_storage, src->stored_size);
 163         dst->size += src->size;
 164
 165         privilegeset_index(dst);
 166 }
 167
 168 static struct PrivilegeSet *
 169 privilegeset_new_orphan(const char *name)
 170 {
 171         struct PrivilegeSet *set;
 172         set = rb_malloc(sizeof *set);
 173         *set = (struct PrivilegeSet) {
 174                 .size = 0,
 175                 .privs = NULL,
 176                 .priv_storage = NULL,
 177                 .shadow = NULL,
 178                 .status = 0,
 179                 .refs = 0,
 180                 .name = rb_strdup(name),
 181         };
 182         return set;
 183 }
 184
 185 static void
 186 privilegeset_free(struct PrivilegeSet *set)
 187 {
 188         if (set == NULL)
 189                 return;
 190
 191         privilegeset_free(set->shadow);
 192         rb_free(set->name);
 193         rb_free(set->privs);
 194         rb_free(set->priv_storage);
 195         rb_free(set);
 196 }
 197
 198 static void
 199 privilegeset_shade(struct PrivilegeSet *set)
 200 {
 201         privilegeset_free(set->shadow);
 202
 203         set->shadow = privilegeset_new_orphan(set->name);
 204         set->shadow->privs = set->privs;
 205         set->shadow->size = set->size;
 206         set->shadow->priv_storage = set->priv_storage;
 207         set->shadow->stored_size = set->stored_size;
 208         set->shadow->allocated_size = set->allocated_size;
 209
 210         set->privs = NULL;
 211         set->size = 0;
 212         set->priv_storage = NULL;
 213         set->stored_size = 0;
 214         set->allocated_size = 0;
 215 }
 216
 217 static void
 218 privilegeset_clear(struct PrivilegeSet *set)
 219 {
 220         rb_free(set->privs);
 221         set->privs = NULL;
 222         set->size = 0;
 223         set->stored_size = 0;
 224 }
 225
 226 bool
 227 privilegeset_in_set(const struct PrivilegeSet *set, const char *priv)
 228 {
 229         s_assert(set != NULL);
 230         s_assert(priv != NULL);
 231
 232         const char **found = bsearch(&priv, set->privs, set->size, sizeof *set->privs, privilegeset_cmp_priv);
 233         return found != NULL;
 234 }
 235
 236 struct PrivilegeSet *
 237 privilegeset_set_new(const char *name, const char *privs, PrivilegeFlags flags)
 238 {
 239         struct PrivilegeSet *set;
 240
 241         set = privilegeset_get_any(name);
 242         if (set != NULL)
 243         {
 244                 if (!(set->status & CONF_ILLEGAL))
 245                         ilog(L_MAIN, "Duplicate privset %s", name);
 246                 set->status &= ~CONF_ILLEGAL;
 247                 privilegeset_clear(set);
 248         }
 249         else
 250         {
 251                 set = privilegeset_new_orphan(name);
 252                 rb_dlinkAdd(set, &set->node, &privilegeset_list);
 253         }
 254         privilegeset_add_privs(set, privs);
 255         set->flags = flags;
 256
 257         return set;
 258 }
 259
 260 struct PrivilegeSet *
 261 privilegeset_extend(const struct PrivilegeSet *parent, const char *name, const char *privs, PrivilegeFlags flags)
 262 {
 263         struct PrivilegeSet *set;
 264
 265         s_assert(parent != NULL);
 266         s_assert(name != NULL);
 267         s_assert(privs != NULL);
 268
 269         set = privilegeset_set_new(name, privs, flags);
 270         privilegeset_add_privilegeset(set, parent);
 271         set->flags = flags;
 272
 273         return set;
 274 }
 275
 276 struct PrivilegeSet *
 277 privilegeset_get(const char *name)
 278 {
 279         struct PrivilegeSet *set;
 280
 281         set = privilegeset_get_any(name);
 282         if (set != NULL && set->status & CONF_ILLEGAL)
 283                 set = NULL;
 284         return set;
 285 }
 286
 287 struct PrivilegeSet *
 288 privilegeset_ref(struct PrivilegeSet *set)
 289 {
 290         s_assert(set != NULL);
 291
 292         set->refs++;
 293
 294         return set;
 295 }
 296
 297 void
 298 privilegeset_unref(struct PrivilegeSet *set)
 299 {
 300         s_assert(set != NULL);
 301
 302         if (set->refs > 0)
 303                 set->refs--;
 304         else
 305                 ilog(L_MAIN, "refs on privset %s is already 0",
 306                                 set->name);
 307         if (set->refs == 0 && set->status & CONF_ILLEGAL)
 308         {
 309                 rb_dlinkDelete(&set->node, &privilegeset_list);
 310
 311                 privilegeset_free(set);
 312         }
 313 }
 314
 315 const struct PrivilegeSet **
 316 privilegeset_diff(const struct PrivilegeSet *old, const struct PrivilegeSet *new)
 317 {
 318         static const char *no_privs[] = { NULL };
 319         static const struct PrivilegeSet empty = { .size = 0, .privs = no_privs };
 320         static struct PrivilegeSet *set_unchanged = NULL,
 321                                    *set_added = NULL,
 322                                    *set_removed = NULL;
 323         static const struct PrivilegeSet *result_sets[3];
 324         static size_t n_privs = 0;
 325         size_t new_size = n_privs ? n_privs : 32;
 326         size_t i = 0, j = 0;
 327
 328         if (result_sets[0] == NULL)
 329         {
 330                 result_sets[0] = set_unchanged = privilegeset_new_orphan("<unchanged>");
 331                 result_sets[1] = set_added = privilegeset_new_orphan("<added>");
 332                 result_sets[2] = set_removed = privilegeset_new_orphan("<removed>");
 333         }
 334
 335         if (old == NULL)
 336                 old = &empty;
 337         if (new == NULL)
 338                 new = &empty;
 339
 340         while (new_size < MAX(old->size, new->size) + 1)
 341                 new_size *= 2;
 342
 343         if (new_size > n_privs)
 344         {
 345                 set_unchanged->privs = rb_realloc(set_unchanged->privs, sizeof *set_unchanged->privs * new_size);
 346                 set_added->privs = rb_realloc(set_added->privs, sizeof *set_added->privs * new_size);
 347                 set_removed->privs = rb_realloc(set_removed->privs, sizeof *set_removed->privs * new_size);
 348         }
 349
 350         const char **res_unchanged = set_unchanged->privs;
 351         const char **res_added = set_added->privs;
 352         const char **res_removed = set_removed->privs;
 353
 354         while (i < old->size || j < new->size)
 355         {
 356                 const char *oldpriv = NULL, *newpriv = NULL;
 357                 int ord = 0;
 358                 if (i < old->size)
 359                         oldpriv = old->privs[i];
 360                 if (j < new->size)
 361                         newpriv = new->privs[j];
 362
 363                 if (oldpriv && newpriv)
 364                         ord = strcmp(oldpriv, newpriv);
 365
 366                 if (newpriv == NULL || ord < 0)
 367                 {
 368                         *res_removed++ = oldpriv;
 369                         i++;
 370                 }
 371                 else if (oldpriv == NULL || ord > 0)
 372                 {
 373                         *res_added++ = newpriv;
 374                         j++;
 375                 }
 376                 else
 377                 {
 378                         *res_unchanged++ = oldpriv;
 379                         i++; j++;
 380                 }
 381         }
 382
 383         *res_removed = *res_added = *res_unchanged = NULL;
 384         set_unchanged->size = res_unchanged - set_unchanged->privs;
 385         set_added->size = res_added - set_added->privs;
 386         set_removed->size = res_removed - set_removed->privs;
 387
 388         return result_sets;
 389 }
 390
 391 void
 392 privilegeset_prepare_rehash()
 393 {
 394         rb_dlink_node *iter;
 395
 396         RB_DLINK_FOREACH(iter, privilegeset_list.head)
 397         {
 398                 struct PrivilegeSet *set = iter->data;
 399
 400                 /* the "default" privset is special and must remain available */
 401                 if (!strcmp(set->name, "default"))
 402                         continue;
 403
 404                 set->status |= CONF_ILLEGAL;
 405                 privilegeset_shade(set);
 406         }
 407 }
 408
 409 void
 410 privilegeset_cleanup_rehash()
 411 {
 412         rb_dlink_node *iter, *next;
 413
 414         RB_DLINK_FOREACH_SAFE(iter, next, privilegeset_list.head)
 415         {
 416                 struct PrivilegeSet *set = iter->data;
 417
 418                 if (set->shadow)
 419                 {
 420                         privilegeset_free(set->shadow);
 421                         set->shadow = NULL;
 422                 }
 423
 424                 privilegeset_ref(set);
 425                 privilegeset_unref(set);
 426         }
 427 }
 428
 429 void
 430 privilegeset_report(struct Client *source_p)
 431 {
 432         rb_dlink_node *ptr;
 433
 434         RB_DLINK_FOREACH(ptr, privilegeset_list.head)
 435         {
 436                 struct PrivilegeSet *set = ptr->data;
 437
 438                 /* use RPL_STATSDEBUG for now -- jilles */
 439                 send_multiline_init(source_p, " ", ":%s %03d %s O :%s ",
 440                                 get_id(&me, source_p),
 441                                 RPL_STATSDEBUG,
 442                                 get_id(source_p, source_p),
 443                                 set->name);
 444                 send_multiline_remote_pad(source_p, &me);
 445                 send_multiline_remote_pad(source_p, source_p);
 446                 for (const char **s = set->privs; s && *s; s++)
 447                         send_multiline_item(source_p, "%s", *s);
 448                 send_multiline_fini(source_p, NULL);
 449         }
 450 }