usr.sbin/rpc.ypupdated/update.c

   1 /*
   2  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
   3  * unrestricted use provided that this legend is included on all tape
   4  * media and as a part of the software program in whole or part.  Users
   5  * may copy or modify Sun RPC without charge, but are not authorized
   6  * to license or distribute it to anyone else except as part of a product or
   7  * program developed by the user or with the express written consent of
   8  * Sun Microsystems, Inc.
   9  *
  10  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  11  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  12  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  13  *
  14  * Sun RPC is provided with no support and without any obligation on the
  15  * part of Sun Microsystems, Inc. to assist in its use, correction,
  16  * modification or enhancement.
  17  *
  18  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  19  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  20  * OR ANY PART THEREOF.
  21  *
  22  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  23  * or profits or other special, indirect and consequential damages, even if
  24  * Sun has been advised of the possibility of such damages.
  25  *
  26  * Sun Microsystems, Inc.
  27  * 2550 Garcia Avenue
  28  * Mountain View, California  94043
  29  *
  30  * @(#)update.c 1.2 91/03/11 Copyr 1986 Sun Micro
  31  * $FreeBSD: src/usr.sbin/rpc.ypupdated/update.c,v 1.8 2007/02/15 02:45:14 trhodes Exp $
  32  * $DragonFly: src/usr.sbin/rpc.ypupdated/update.c,v 1.4 2005/11/25 00:32:49 swildner Exp $
  33  */
  34
  35 /*
  36  * Copyright (C) 1986, 1989, Sun Microsystems, Inc.
  37  */
  38
  39 /*
  40  * Administrative tool to add a new user to the publickey database
  41  */
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44 #include <unistd.h>
  45 #include <rpc/rpc.h>
  46 #include <rpc/key_prot.h>
  47 #ifdef YP
  48 #include <rpcsvc/yp_prot.h>
  49 #include <rpcsvc/ypclnt.h>
  50 #include <sys/wait.h>
  51 #include <netdb.h>
  52 #endif  /* YP */
  53 #include <pwd.h>
  54 #include <string.h>
  55 #include <sys/resource.h>
  56 #include <stdlib.h>
  57 #include "ypupdated_extern.h"
  58
  59 #ifdef YP
  60 #define MAXMAPNAMELEN 256
  61 #else
  62 #define YPOP_CHANGE 1                   /* change, do not add */
  63 #define YPOP_INSERT 2                   /* add, do not change */
  64 #define YPOP_DELETE 3                   /* delete this entry */
  65 #define YPOP_STORE  4                   /* add, or change */
  66 #endif
  67
  68 #ifdef YP
  69 static char SHELL[] = "/bin/sh";
  70 static char YPDBPATH[]="/var/yp";       /* This is defined but not used! */
  71 static char PKMAP[] = "publickey.byname";
  72 static char UPDATEFILE[] = "updaters";
  73 static char PKFILE[] = "/etc/publickey";
  74 #endif  /* YP */
  75
  76 #ifdef YP
  77 static int _openchild(char *, FILE **, FILE **);
  78
  79 /*
  80  * Determine if requester is allowed to update the given map,
  81  * and update it if so. Returns the yp status, which is zero
  82  * if there is no access violation.
  83  */
  84 int
  85 mapupdate(char *requester, char *mapname, u_int op, u_int keylen, char *key,
  86           u_int datalen, char *data)
  87 {
  88         char updater[MAXMAPNAMELEN + 40];
  89         FILE *childargs;
  90         FILE *childrslt;
  91 #ifdef WEXITSTATUS
  92         int status;
  93 #else
  94         union wait status;
  95 #endif
  96         pid_t pid;
  97         u_int yperrno;
  98
  99
 100 #ifdef DEBUG
 101         printf("%s %s\n", key, data);
 102 #endif
 103         sprintf(updater, "make -s -f %s/%s %s", YPDBPATH, /* !!! */
 104                                         UPDATEFILE, mapname);
 105         pid = _openchild(updater, &childargs, &childrslt);
 106         if (pid < 0) {
 107                 return (YPERR_YPERR);
 108         }
 109
 110         /*
 111          * Write to child
 112          */
 113         fprintf(childargs, "%s\n", requester);
 114         fprintf(childargs, "%u\n", op);
 115         fprintf(childargs, "%u\n", keylen);
 116         fwrite(key, (int)keylen, 1, childargs);
 117         fprintf(childargs, "\n");
 118         fprintf(childargs, "%u\n", datalen);
 119         fwrite(data, (int)datalen, 1, childargs);
 120         fprintf(childargs, "\n");
 121         fclose(childargs);
 122
 123         /*
 124          * Read from child
 125          */
 126         fscanf(childrslt, "%d", &yperrno);
 127         fclose(childrslt);
 128
 129         wait(&status);
 130 #ifdef WEXITSTATUS
 131         if (WEXITSTATUS(status) != 0)
 132 #else
 133         if (status.w_retcode != 0)
 134 #endif
 135                 return (YPERR_YPERR);
 136         return (yperrno);
 137 }
 138
 139 /*
 140  * returns pid, or -1 for failure
 141  */
 142 static int
 143 _openchild(char *command, FILE **fto, FILE **ffrom)
 144 {
 145         int i;
 146         pid_t pid;
 147         int pdto[2];
 148         int pdfrom[2];
 149         char *com;
 150         struct rlimit rl;
 151
 152         if (pipe(pdto) < 0) {
 153                 goto error1;
 154         }
 155         if (pipe(pdfrom) < 0) {
 156                 goto error2;
 157         }
 158         switch (pid = fork()) {
 159         case -1:
 160                 goto error3;
 161
 162         case 0:
 163                 /*
 164                  * child: read from pdto[0], write into pdfrom[1]
 165                  */
 166                 close(0);
 167                 dup(pdto[0]);
 168                 close(1);
 169                 dup(pdfrom[1]);
 170                 getrlimit(RLIMIT_NOFILE, &rl);
 171                 for (i = rl.rlim_max - 1; i >= 3; i--) {
 172                         close(i);
 173                 }
 174                 com = malloc((unsigned) strlen(command) + 6);
 175                 if (com == NULL) {
 176                         _exit(~0);
 177                 }
 178                 sprintf(com, "exec %s", command);
 179                 execl(SHELL, basename(SHELL), "-c", com, NULL);
 180                 _exit(~0);
 181
 182         default:
 183                 /*
 184                  * parent: write into pdto[1], read from pdfrom[0]
 185                  */
 186                 *fto = fdopen(pdto[1], "w");
 187                 close(pdto[0]);
 188                 *ffrom = fdopen(pdfrom[0], "r");
 189                 close(pdfrom[1]);
 190                 break;
 191         }
 192         return (pid);
 193
 194         /*
 195          * error cleanup and return
 196          */
 197 error3:
 198         close(pdfrom[0]);
 199         close(pdfrom[1]);
 200 error2:
 201         close(pdto[0]);
 202         close(pdto[1]);
 203 error1:
 204         return (-1);
 205 }
 206
 207 static char *
 208 basename(char *path)
 209 {
 210         char *p;
 211
 212         p = strrchr(path, '/');
 213         if (p == NULL) {
 214                 return (path);
 215         } else {
 216                 return (p + 1);
 217         }
 218 }
 219
 220 #else /* YP */
 221
 222 static int match(char *, char *);
 223
 224 /*
 225  * Determine if requester is allowed to update the given map,
 226  * and update it if so. Returns the status, which is zero
 227  * if there is no access violation. This function updates
 228  * the local file and then shuts up.
 229  */
 230 int
 231 localupdate(char *name, char *filename, u_int op, u_int keylen __unused,
 232             char *key, u_int datalen __unused, char *data)
 233 {
 234         char line[256];
 235         FILE *rf;
 236         FILE *wf;
 237         char *tmpname;
 238         int err;
 239
 240         /*
 241          * Check permission
 242          */
 243         if (strcmp(name, key) != 0) {
 244                 return (ERR_ACCESS);
 245         }
 246         if (strcmp(name, "nobody") == 0) {
 247                 /*
 248                  * Can't change "nobody"s key.
 249                  */
 250                 return (ERR_ACCESS);
 251         }
 252
 253         /*
 254          * Open files
 255          */
 256         tmpname = malloc(strlen(filename) + 4);
 257         if (tmpname == NULL) {
 258                 return (ERR_MALLOC);
 259         }
 260         sprintf(tmpname, "%s.tmp", filename);
 261         rf = fopen(filename, "r");
 262         if (rf == NULL) {
 263                 return (ERR_READ);
 264         }
 265         wf = fopen(tmpname, "w");
 266         if (wf == NULL) {
 267                 return (ERR_WRITE);
 268         }
 269         err = -1;
 270         while (fgets(line, sizeof (line), rf)) {
 271                 if (err < 0 && match(line, name)) {
 272                         switch (op) {
 273                         case YPOP_INSERT:
 274                                 err = ERR_KEY;
 275                                 break;
 276                         case YPOP_STORE:
 277                         case YPOP_CHANGE:
 278                                 fprintf(wf, "%s %s\n", key, data);
 279                                 err = 0;
 280                                 break;
 281                         case YPOP_DELETE:
 282                                 /* do nothing */
 283                                 err = 0;
 284                                 break;
 285                         }
 286                 } else {
 287                         fputs(line, wf);
 288                 }
 289         }
 290         if (err < 0) {
 291                 switch (op) {
 292                 case YPOP_CHANGE:
 293                 case YPOP_DELETE:
 294                         err = ERR_KEY;
 295                         break;
 296                 case YPOP_INSERT:
 297                 case YPOP_STORE:
 298                         err = 0;
 299                         fprintf(wf, "%s %s\n", key, data);
 300                         break;
 301                 }
 302         }
 303         fclose(wf);
 304         fclose(rf);
 305         if (err == 0) {
 306                 if (rename(tmpname, filename) < 0) {
 307                         return (ERR_DBASE);
 308                 }
 309         } else {
 310                 if (unlink(tmpname) < 0) {
 311                         return (ERR_DBASE);
 312                 }
 313         }
 314         return (err);
 315 }
 316
 317 static int
 318 match(char *line, char *name)
 319 {
 320         int len;
 321
 322         len = strlen(name);
 323         return (strncmp(line, name, len) == 0 &&
 324                 (line[len] == ' ' || line[len] == '\t'));
 325 }
 326 #endif /* !YP */