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  */
  33
  34 /*
  35  * Copyright (C) 1986, 1989, Sun Microsystems, Inc.
  36  */
  37
  38 /*
  39  * Administrative tool to add a new user to the publickey database
  40  */
  41 #include <stdio.h>
  42 #include <stdlib.h>
  43 #include <unistd.h>
  44 #include <rpc/rpc.h>
  45 #include <rpc/key_prot.h>
  46 #ifdef YP
  47 #include <rpcsvc/yp_prot.h>
  48 #include <rpcsvc/ypclnt.h>
  49 #include <sys/wait.h>
  50 #include <netdb.h>
  51 #endif  /* YP */
  52 #include <pwd.h>
  53 #include <string.h>
  54 #include <sys/resource.h>
  55 #include "ypupdated_extern.h"
  56
  57 #ifdef YP
  58 #define MAXMAPNAMELEN 256
  59 #else
  60 #define YPOP_CHANGE 1                   /* change, do not add */
  61 #define YPOP_INSERT 2                   /* add, do not change */
  62 #define YPOP_DELETE 3                   /* delete this entry */
  63 #define YPOP_STORE  4                   /* add, or change */
  64 #endif
  65
  66 #ifdef YP
  67 static char SHELL[] = "/bin/sh";
  68 static char YPDBPATH[]="/var/yp";       /* This is defined but not used! */
  69 static char PKMAP[] = "publickey.byname";
  70 static char UPDATEFILE[] = "updaters";
  71 static char PKFILE[] = "/etc/publickey";
  72 #endif  /* YP */
  73
  74 #ifdef YP
  75 static int _openchild(char *, FILE **, FILE **);
  76
  77 /*
  78  * Determine if requester is allowed to update the given map,
  79  * and update it if so. Returns the yp status, which is zero
  80  * if there is no access violation.
  81  */
  82 int
  83 mapupdate(char *requester, char *mapname, u_int op, u_int keylen, char *key,
  84           u_int datalen, char *data)
  85 {
  86         char updater[MAXMAPNAMELEN + 40];
  87         FILE *childargs;
  88         FILE *childrslt;
  89 #ifdef WEXITSTATUS
  90         int status;
  91 #else
  92         union wait status;
  93 #endif
  94         pid_t pid;
  95         u_int yperrno;
  96
  97
  98 #ifdef DEBUG
  99         printf("%s %s\n", key, data);
 100 #endif
 101         sprintf(updater, "make -s -f %s/%s %s", YPDBPATH, /* !!! */
 102                                         UPDATEFILE, mapname);
 103         pid = _openchild(updater, &childargs, &childrslt);
 104         if (pid < 0) {
 105                 return (YPERR_YPERR);
 106         }
 107
 108         /*
 109          * Write to child
 110          */
 111         fprintf(childargs, "%s\n", requester);
 112         fprintf(childargs, "%u\n", op);
 113         fprintf(childargs, "%u\n", keylen);
 114         fwrite(key, (int)keylen, 1, childargs);
 115         fprintf(childargs, "\n");
 116         fprintf(childargs, "%u\n", datalen);
 117         fwrite(data, (int)datalen, 1, childargs);
 118         fprintf(childargs, "\n");
 119         fclose(childargs);
 120
 121         /*
 122          * Read from child
 123          */
 124         fscanf(childrslt, "%d", &yperrno);
 125         fclose(childrslt);
 126
 127         wait(&status);
 128 #ifdef WEXITSTATUS
 129         if (WEXITSTATUS(status) != 0)
 130 #else
 131         if (status.w_retcode != 0)
 132 #endif
 133                 return (YPERR_YPERR);
 134         return (yperrno);
 135 }
 136
 137 /*
 138  * returns pid, or -1 for failure
 139  */
 140 static int
 141 _openchild(char *command, FILE **fto, FILE **ffrom)
 142 {
 143         int i;
 144         pid_t pid;
 145         int pdto[2];
 146         int pdfrom[2];
 147         char *com;
 148         struct rlimit rl;
 149
 150         if (pipe(pdto) < 0) {
 151                 goto error1;
 152         }
 153         if (pipe(pdfrom) < 0) {
 154                 goto error2;
 155         }
 156         switch (pid = fork()) {
 157         case -1:
 158                 goto error3;
 159
 160         case 0:
 161                 /*
 162                  * child: read from pdto[0], write into pdfrom[1]
 163                  */
 164                 close(0);
 165                 dup(pdto[0]);
 166                 close(1);
 167                 dup(pdfrom[1]);
 168                 getrlimit(RLIMIT_NOFILE, &rl);
 169                 for (i = rl.rlim_max - 1; i >= 3; i--) {
 170                         close(i);
 171                 }
 172                 com = malloc((unsigned) strlen(command) + 6);
 173                 if (com == NULL) {
 174                         _exit(~0);
 175                 }
 176                 sprintf(com, "exec %s", command);
 177                 execl(SHELL, basename(SHELL), "-c", com, NULL);
 178                 _exit(~0);
 179
 180         default:
 181                 /*
 182                  * parent: write into pdto[1], read from pdfrom[0]
 183                  */
 184                 *fto = fdopen(pdto[1], "w");
 185                 close(pdto[0]);
 186                 *ffrom = fdopen(pdfrom[0], "r");
 187                 close(pdfrom[1]);
 188                 break;
 189         }
 190         return (pid);
 191
 192         /*
 193          * error cleanup and return
 194          */
 195 error3:
 196         close(pdfrom[0]);
 197         close(pdfrom[1]);
 198 error2:
 199         close(pdto[0]);
 200         close(pdto[1]);
 201 error1:
 202         return (-1);
 203 }
 204
 205 static char *
 206 basename(char *path)
 207 {
 208         char *p;
 209
 210         p = strrchr(path, '/');
 211         if (p == NULL) {
 212                 return (path);
 213         } else {
 214                 return (p + 1);
 215         }
 216 }
 217
 218 #else /* YP */
 219
 220 static int match(char *, char *);
 221
 222 /*
 223  * Determine if requester is allowed to update the given map,
 224  * and update it if so. Returns the status, which is zero
 225  * if there is no access violation. This function updates
 226  * the local file and then shuts up.
 227  */
 228 int
 229 localupdate(char *name, char *filename, u_int op, u_int keylen __unused,
 230             char *key, u_int datalen __unused, char *data)
 231 {
 232         char line[256];
 233         FILE *rf;
 234         FILE *wf;
 235         char *tmpname;
 236         int err;
 237
 238         /*
 239          * Check permission
 240          */
 241         if (strcmp(name, key) != 0) {
 242                 return (ERR_ACCESS);
 243         }
 244         if (strcmp(name, "nobody") == 0) {
 245                 /*
 246                  * Can't change "nobody"s key.
 247                  */
 248                 return (ERR_ACCESS);
 249         }
 250
 251         /*
 252          * Open files
 253          */
 254         tmpname = malloc(strlen(filename) + 4);
 255         if (tmpname == NULL) {
 256                 return (ERR_MALLOC);
 257         }
 258         sprintf(tmpname, "%s.tmp", filename);
 259         rf = fopen(filename, "r");
 260         if (rf == NULL) {
 261                 return (ERR_READ);
 262         }
 263         wf = fopen(tmpname, "w");
 264         if (wf == NULL) {
 265                 return (ERR_WRITE);
 266         }
 267         err = -1;
 268         while (fgets(line, sizeof (line), rf)) {
 269                 if (err < 0 && match(line, name)) {
 270                         switch (op) {
 271                         case YPOP_INSERT:
 272                                 err = ERR_KEY;
 273                                 break;
 274                         case YPOP_STORE:
 275                         case YPOP_CHANGE:
 276                                 fprintf(wf, "%s %s\n", key, data);
 277                                 err = 0;
 278                                 break;
 279                         case YPOP_DELETE:
 280                                 /* do nothing */
 281                                 err = 0;
 282                                 break;
 283                         }
 284                 } else {
 285                         fputs(line, wf);
 286                 }
 287         }
 288         if (err < 0) {
 289                 switch (op) {
 290                 case YPOP_CHANGE:
 291                 case YPOP_DELETE:
 292                         err = ERR_KEY;
 293                         break;
 294                 case YPOP_INSERT:
 295                 case YPOP_STORE:
 296                         err = 0;
 297                         fprintf(wf, "%s %s\n", key, data);
 298                         break;
 299                 }
 300         }
 301         fclose(wf);
 302         fclose(rf);
 303         if (err == 0) {
 304                 if (rename(tmpname, filename) < 0) {
 305                         return (ERR_DBASE);
 306                 }
 307         } else {
 308                 if (unlink(tmpname) < 0) {
 309                         return (ERR_DBASE);
 310                 }
 311         }
 312         return (err);
 313 }
 314
 315 static int
 316 match(char *line, char *name)
 317 {
 318         int len;
 319
 320         len = strlen(name);
 321         return (strncmp(line, name, len) == 0 &&
 322                 (line[len] == ' ' || line[len] == '\t'));
 323 }
 324 #endif /* !YP */