commands/pax/cache.c

   1 /*-
   2  * Copyright (c) 1992 Keith Muller.
   3  * Copyright (c) 1992, 1993
   4  *      The Regents of the University of California.  All rights reserved.
   5  *
   6  * This code is derived from software contributed to Berkeley by
   7  * Keith Muller of the University of California, San Diego.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #ifndef lint
  35 #if 0
  36 static char sccsid[] = "@(#)cache.c     8.1 (Berkeley) 5/31/93";
  37 #endif
  38 #endif /* not lint */
  39
  40 #include <sys/types.h>
  41 #include <sys/stat.h>
  42 #include <string.h>
  43 #include <stdio.h>
  44 #include <pwd.h>
  45 #include <grp.h>
  46 #include <unistd.h>
  47 #include <stdlib.h>
  48 #include "pax.h"
  49 #include "cache.h"
  50 #include "extern.h"
  51
  52 /*
  53  * routines that control user, group, uid and gid caches (for the archive
  54  * member print routine).
  55  * IMPORTANT:
  56  * these routines cache BOTH hits and misses, a major performance improvement
  57  */
  58
  59 static  int pwopn = 0;          /* is password file open */
  60 static  int gropn = 0;          /* is group file open */
  61 static UIDC **uidtb = NULL;     /* uid to name cache */
  62 static GIDC **gidtb = NULL;     /* gid to name cache */
  63 static UIDC **usrtb = NULL;     /* user name to uid cache */
  64 static GIDC **grptb = NULL;     /* group name to gid cache */
  65
  66 /*
  67  * uidtb_start
  68  *      creates an an empty uidtb
  69  * Return:
  70  *      0 if ok, -1 otherwise
  71  */
  72
  73 int
  74 uidtb_start(void)
  75 {
  76         static int fail = 0;
  77
  78         if (uidtb != NULL)
  79                 return(0);
  80         if (fail)
  81                 return(-1);
  82         if ((uidtb = (UIDC **)calloc(UID_SZ, sizeof(UIDC *))) == NULL) {
  83                 ++fail;
  84                 paxwarn(1, "Unable to allocate memory for user id cache table");
  85                 return(-1);
  86         }
  87         return(0);
  88 }
  89
  90 /*
  91  * gidtb_start
  92  *      creates an an empty gidtb
  93  * Return:
  94  *      0 if ok, -1 otherwise
  95  */
  96
  97 int
  98 gidtb_start(void)
  99 {
 100         static int fail = 0;
 101
 102         if (gidtb != NULL)
 103                 return(0);
 104         if (fail)
 105                 return(-1);
 106         if ((gidtb = (GIDC **)calloc(GID_SZ, sizeof(GIDC *))) == NULL) {
 107                 ++fail;
 108                 paxwarn(1, "Unable to allocate memory for group id cache table");
 109                 return(-1);
 110         }
 111         return(0);
 112 }
 113
 114 /*
 115  * usrtb_start
 116  *      creates an an empty usrtb
 117  * Return:
 118  *      0 if ok, -1 otherwise
 119  */
 120
 121 int
 122 usrtb_start(void)
 123 {
 124         static int fail = 0;
 125
 126         if (usrtb != NULL)
 127                 return(0);
 128         if (fail)
 129                 return(-1);
 130         if ((usrtb = (UIDC **)calloc(UNM_SZ, sizeof(UIDC *))) == NULL) {
 131                 ++fail;
 132                 paxwarn(1, "Unable to allocate memory for user name cache table");
 133                 return(-1);
 134         }
 135         return(0);
 136 }
 137
 138 /*
 139  * grptb_start
 140  *      creates an an empty grptb
 141  * Return:
 142  *      0 if ok, -1 otherwise
 143  */
 144
 145 int
 146 grptb_start(void)
 147 {
 148         static int fail = 0;
 149
 150         if (grptb != NULL)
 151                 return(0);
 152         if (fail)
 153                 return(-1);
 154         if ((grptb = (GIDC **)calloc(GNM_SZ, sizeof(GIDC *))) == NULL) {
 155                 ++fail;
 156                 paxwarn(1,"Unable to allocate memory for group name cache table");
 157                 return(-1);
 158         }
 159         return(0);
 160 }
 161
 162 /*
 163  * name_uid()
 164  *      caches the name (if any) for the uid. If frc set, we always return the
 165  *      the stored name (if valid or invalid match). We use a simple hash table.
 166  * Return
 167  *      Pointer to stored name (or an empty string).
 168  */
 169
 170 const char *
 171 name_uid(uid_t uid, int frc)
 172 {
 173         struct passwd *pw;
 174         UIDC *ptr;
 175
 176         if ((uidtb == NULL) && (uidtb_start() < 0))
 177                 return("");
 178
 179         /*
 180          * see if we have this uid cached
 181          */
 182         ptr = uidtb[uid % UID_SZ];
 183         if ((ptr != NULL) && (ptr->valid > 0) && (ptr->uid == uid)) {
 184                 /*
 185                  * have an entry for this uid
 186                  */
 187                 if (frc || (ptr->valid == VALID))
 188                         return(ptr->name);
 189                 return("");
 190         }
 191
 192         /*
 193          * No entry for this uid, we will add it
 194          */
 195         if (!pwopn) {
 196                 setpassent(1);
 197                 ++pwopn;
 198         }
 199         if (ptr == NULL)
 200                 ptr = uidtb[uid % UID_SZ] = (UIDC *)malloc(sizeof(UIDC));
 201
 202         if ((pw = getpwuid(uid)) == NULL) {
 203                 /*
 204                  * no match for this uid in the local password file
 205                  * a string that is the uid in numeric format
 206                  */
 207                 if (ptr == NULL)
 208                         return("");
 209                 ptr->uid = uid;
 210                 ptr->valid = INVALID;
 211 #               ifdef NET2_STAT
 212                 (void)snprintf(ptr->name, sizeof(ptr->name), "%u", uid);
 213 #               else
 214                 (void)snprintf(ptr->name, sizeof(ptr->name), "%lu",
 215                                (unsigned long)uid);
 216 #               endif
 217                 if (frc == 0)
 218                         return("");
 219         } else {
 220                 /*
 221                  * there is an entry for this uid in the password file
 222                  */
 223                 if (ptr == NULL)
 224                         return(pw->pw_name);
 225                 ptr->uid = uid;
 226                 (void)strncpy(ptr->name, pw->pw_name, UNMLEN - 1);
 227                 ptr->name[UNMLEN-1] = '\0';
 228                 ptr->valid = VALID;
 229         }
 230         return(ptr->name);
 231 }
 232
 233 /*
 234  * name_gid()
 235  *      caches the name (if any) for the gid. If frc set, we always return the
 236  *      the stored name (if valid or invalid match). We use a simple hash table.
 237  * Return
 238  *      Pointer to stored name (or an empty string).
 239  */
 240
 241 const char *
 242 name_gid(gid_t gid, int frc)
 243 {
 244         struct group *gr;
 245         GIDC *ptr;
 246
 247         if ((gidtb == NULL) && (gidtb_start() < 0))
 248                 return("");
 249
 250         /*
 251          * see if we have this gid cached
 252          */
 253         ptr = gidtb[gid % GID_SZ];
 254         if ((ptr != NULL) && (ptr->valid > 0) && (ptr->gid == gid)) {
 255                 /*
 256                  * have an entry for this gid
 257                  */
 258                 if (frc || (ptr->valid == VALID))
 259                         return(ptr->name);
 260                 return("");
 261         }
 262
 263         /*
 264          * No entry for this gid, we will add it
 265          */
 266         if (!gropn) {
 267                 setgroupent(1);
 268                 ++gropn;
 269         }
 270         if (ptr == NULL)
 271                 ptr = gidtb[gid % GID_SZ] = (GIDC *)malloc(sizeof(GIDC));
 272
 273         if ((gr = getgrgid(gid)) == NULL) {
 274                 /*
 275                  * no match for this gid in the local group file, put in
 276                  * a string that is the gid in numeric format
 277                  */
 278                 if (ptr == NULL)
 279                         return("");
 280                 ptr->gid = gid;
 281                 ptr->valid = INVALID;
 282 #               ifdef NET2_STAT
 283                 (void)snprintf(ptr->name, sizeof(ptr->name), "%u", gid);
 284 #               else
 285                 (void)snprintf(ptr->name, sizeof(ptr->name), "%lu",
 286                                (unsigned long)gid);
 287 #               endif
 288                 if (frc == 0)
 289                         return("");
 290         } else {
 291                 /*
 292                  * there is an entry for this group in the group file
 293                  */
 294                 if (ptr == NULL)
 295                         return(gr->gr_name);
 296                 ptr->gid = gid;
 297                 (void)strncpy(ptr->name, gr->gr_name, GNMLEN - 1);
 298                 ptr->name[GNMLEN-1] = '\0';
 299                 ptr->valid = VALID;
 300         }
 301         return(ptr->name);
 302 }
 303
 304 /*
 305  * uid_name()
 306  *      caches the uid for a given user name. We use a simple hash table.
 307  * Return
 308  *      the uid (if any) for a user name, or a -1 if no match can be found
 309  */
 310
 311 int
 312 uid_name(char *name, uid_t *uid)
 313 {
 314         struct passwd *pw;
 315         UIDC *ptr;
 316         int namelen;
 317
 318         /*
 319          * return -1 for mangled names
 320          */
 321         if (((namelen = strlen(name)) == 0) || (name[0] == '\0'))
 322                 return(-1);
 323         if ((usrtb == NULL) && (usrtb_start() < 0))
 324                 return(-1);
 325
 326         /*
 327          * look up in hash table, if found and valid return the uid,
 328          * if found and invalid, return a -1
 329          */
 330         ptr = usrtb[st_hash(name, namelen, UNM_SZ)];
 331         if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) {
 332                 if (ptr->valid == INVALID)
 333                         return(-1);
 334                 *uid = ptr->uid;
 335                 return(0);
 336         }
 337
 338         if (!pwopn) {
 339                 setpassent(1);
 340                 ++pwopn;
 341         }
 342
 343         if (ptr == NULL)
 344                 ptr = usrtb[st_hash(name, namelen, UNM_SZ)] =
 345                   (UIDC *)malloc(sizeof(UIDC));
 346
 347         /*
 348          * no match, look it up, if no match store it as an invalid entry,
 349          * or store the matching uid
 350          */
 351         if (ptr == NULL) {
 352                 if ((pw = getpwnam(name)) == NULL)
 353                         return(-1);
 354                 *uid = pw->pw_uid;
 355                 return(0);
 356         }
 357         (void)strncpy(ptr->name, name, UNMLEN - 1);
 358         ptr->name[UNMLEN-1] = '\0';
 359         if ((pw = getpwnam(name)) == NULL) {
 360                 ptr->valid = INVALID;
 361                 return(-1);
 362         }
 363         ptr->valid = VALID;
 364         *uid = ptr->uid = pw->pw_uid;
 365         return(0);
 366 }
 367
 368 /*
 369  * gid_name()
 370  *      caches the gid for a given group name. We use a simple hash table.
 371  * Return
 372  *      the gid (if any) for a group name, or a -1 if no match can be found
 373  */
 374
 375 int
 376 gid_name(char *name, gid_t *gid)
 377 {
 378         struct group *gr;
 379         GIDC *ptr;
 380         int namelen;
 381
 382         /*
 383          * return -1 for mangled names
 384          */
 385         if (((namelen = strlen(name)) == 0) || (name[0] == '\0'))
 386                 return(-1);
 387         if ((grptb == NULL) && (grptb_start() < 0))
 388                 return(-1);
 389
 390         /*
 391          * look up in hash table, if found and valid return the uid,
 392          * if found and invalid, return a -1
 393          */
 394         ptr = grptb[st_hash(name, namelen, GID_SZ)];
 395         if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) {
 396                 if (ptr->valid == INVALID)
 397                         return(-1);
 398                 *gid = ptr->gid;
 399                 return(0);
 400         }
 401
 402         if (!gropn) {
 403                 setgroupent(1);
 404                 ++gropn;
 405         }
 406         if (ptr == NULL)
 407                 ptr = grptb[st_hash(name, namelen, GID_SZ)] =
 408                   (GIDC *)malloc(sizeof(GIDC));
 409
 410         /*
 411          * no match, look it up, if no match store it as an invalid entry,
 412          * or store the matching gid
 413          */
 414         if (ptr == NULL) {
 415                 if ((gr = getgrnam(name)) == NULL)
 416                         return(-1);
 417                 *gid = gr->gr_gid;
 418                 return(0);
 419         }
 420
 421         (void)strncpy(ptr->name, name, GNMLEN - 1);
 422         ptr->name[GNMLEN-1] = '\0';
 423         if ((gr = getgrnam(name)) == NULL) {
 424                 ptr->valid = INVALID;
 425                 return(-1);
 426         }
 427         ptr->valid = VALID;
 428         *gid = ptr->gid = gr->gr_gid;
 429         return(0);
 430 }