usr/src/cmd/keyserv/keylogin.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  27 /*        All Rights Reserved   */
  28
  29 /*
  30  * University Copyright- Copyright (c) 1982, 1986, 1988
  31  * The Regents of the University of California
  32  * All Rights Reserved
  33  *
  34  * University Acknowledgment- Portions of this document are derived from
  35  * software developed by the University of California, Berkeley, and its
  36  * contributors.
  37  */
  38
  39 #pragma ident   "%Z%%M% %I%     %E% SMI"
  40
  41 /*
  42  * Set secret key on local machine
  43  */
  44 #include <stdio.h>
  45 #include <rpc/rpc.h>
  46 #include <rpc/key_prot.h>
  47 #include <nfs/nfs.h>                            /* to revoke existing creds */
  48 #include <nfs/nfssys.h>
  49 #include <string.h>
  50 #include <rpcsvc/nis_dhext.h>
  51
  52 #define ROOTKEY_FILE "/etc/.rootkey"
  53 #define ROOTKEY_FILE_BACKUP     "/etc/.rootkey.bak"
  54 /* Should last until 16384-bit DH keys */
  55 #define MAXROOTKEY_LINE_LEN     4224
  56 #define MAXROOTKEY_LEN          4096
  57
  58 extern int key_setnet_g();
  59
  60 static void logout_curr_key();
  61 static int mkrootkey;
  62
  63 static char *sec_domain = NULL;
  64 static char local_domain[MAXNETNAMELEN + 1];
  65
  66 /*
  67  * fgets is broken in that if it reads a NUL character it will always return
  68  * EOF.  This replacement can deal with NULs
  69  */
  70 static char *
  71 fgets_ignorenul(char *s, int n, FILE *stream)
  72 {
  73         int fildes = fileno(stream);
  74         int i = 0;
  75         int rs = 0;
  76         char c;
  77
  78         if (fildes < 0)
  79                 return (NULL);
  80
  81         while (i < n - 1) {
  82                 rs = read(fildes, &c, 1);
  83                 switch (rs) {
  84                 case 1:
  85                         break;
  86                 case 0:
  87                         /* EOF */
  88                         if (i > 0)
  89                                 s[i] = '\0';
  90                         return (NULL);
  91                         break;
  92                 default:
  93                         return (NULL);
  94                 }
  95                 switch (c) {
  96                 case '\0':
  97                         break;
  98                 case '\n':
  99                         s[i] = c;
 100                         s[++i] = '\0';
 101                         return (s);
 102                 default:
 103                 if (c != '\0')
 104                         s[i++] = c;
 105                 }
 106         }
 107         s[i] = '\0';
 108         return (s);
 109 }
 110
 111
 112 /* write unencrypted secret key into root key file */
 113 static void
 114 write_rootkey(char *secret, char *flavor, keylen_t keylen, algtype_t algtype)
 115 {
 116         char            line[MAXROOTKEY_LINE_LEN];
 117         char            keyent[MAXROOTKEY_LEN];
 118         algtype_t       atent;
 119         int             rootfd, bakfd, hexkeybytes;
 120         bool_t          lineone = TRUE;
 121         bool_t          gotit = FALSE;
 122         FILE            *rootfile, *bakfile;
 123
 124         unlink(ROOTKEY_FILE_BACKUP);
 125         if ((rename(ROOTKEY_FILE, ROOTKEY_FILE_BACKUP)) < 0) {
 126                 if ((bakfd = creat(ROOTKEY_FILE_BACKUP, 0600)) < 0) {
 127                         perror("Could not create /etc/.rootkey.bak");
 128                         goto rootkey_err;
 129                 }
 130                 close(bakfd);
 131         }
 132
 133         if ((rootfd = open(ROOTKEY_FILE, O_WRONLY+O_CREAT, 0600)) < 0) {
 134                 perror("Could not open /etc/.rootkey for writing");
 135                 fprintf(stderr,
 136                         "Attempting to restore original /etc/.rootkey\n");
 137                 (void) rename(ROOTKEY_FILE_BACKUP, ROOTKEY_FILE);
 138                 goto rootkey_err;
 139         }
 140         if (!(rootfile = fdopen(rootfd, "w"))) {
 141                 perror("Could not open /etc/.rootkey for writing");
 142                 fprintf(stderr,
 143                         "Attempting to restore original /etc/.rootkey\n");
 144                 close(rootfd);
 145                 unlink(ROOTKEY_FILE);
 146                 rename(ROOTKEY_FILE_BACKUP, ROOTKEY_FILE);
 147                 goto rootkey_err;
 148         }
 149         if (!(bakfile = fopen(ROOTKEY_FILE_BACKUP, "r"))) {
 150                 perror("Could not open /etc/.rootkey.bak for reading");
 151                 fprintf(stderr,
 152                         "Attempting to restore original /etc/.rootkey\n");
 153                 (void) fclose(rootfile);
 154                 unlink(ROOTKEY_FILE);
 155                 rename(ROOTKEY_FILE_BACKUP, ROOTKEY_FILE);
 156                 goto rootkey_err;
 157         }
 158
 159         hexkeybytes = ((keylen + 7) / 8) * 2;
 160
 161         while (fgets_ignorenul(line, MAXROOTKEY_LINE_LEN, bakfile)) {
 162                 if (sscanf(line, "%s %d", keyent, &atent) < 2) {
 163                         /*
 164                          * No encryption algorithm found in the file
 165                          * (atent) so default to DES.
 166                          */
 167                         atent = AUTH_DES_ALGTYPE;
 168                 }
 169                 /*
 170                  * 192-bit keys always go on the first line
 171                  */
 172                 if (lineone) {
 173                         lineone = FALSE;
 174                         if (keylen == 192) {
 175                                 gotit = TRUE;
 176                                 fprintf(rootfile, "%s\n", secret);
 177                         } else
 178                                 fprintf(rootfile, "%s", line);
 179                         (void) fflush(rootfile);
 180                 } else {
 181                         if ((strlen(keyent) == hexkeybytes) &&
 182                             (atent == algtype)) {
 183                                 /*
 184                                  * Silently remove lines with the same
 185                                  * keylen/algtype
 186                                  */
 187                                 if (gotit)
 188                                         continue;
 189                                 else
 190                                         gotit = TRUE;
 191
 192                                 fprintf(rootfile, "%s %d\n", secret, algtype);
 193                         } else
 194                                 fprintf(rootfile, "%s", line);
 195                         (void) fflush(rootfile);
 196                 }
 197         }
 198
 199         /* Append key to rootkey file */
 200         if (!gotit) {
 201                 if (keylen == 192)
 202                         fprintf(rootfile, "%s\n", secret);
 203                 else {
 204                         if (lineone)
 205                                 fprintf(rootfile, "\n");
 206                         fprintf(rootfile, "%s %d\n", secret, algtype);
 207                 }
 208         }
 209         (void) fflush(rootfile);
 210         fclose(rootfile);
 211         fclose(bakfile);
 212         unlink(ROOTKEY_FILE_BACKUP);
 213         if (keylen == 192)
 214                 fprintf(stderr, "Wrote secret key into %s\n", ROOTKEY_FILE);
 215         else
 216                 fprintf(stderr, "Wrote %s key into %s\n", flavor,
 217                         ROOTKEY_FILE);
 218         return;
 219
 220 rootkey_err:
 221         fprintf(stderr, "WARNING: Could not write %s key to /etc/.rootkey\n",
 222                 flavor);
 223 }
 224
 225 /* Perform AUTH_DES keylogin */
 226 static int
 227 oldkeylogin(char *fullname, char *pass)
 228 {
 229         char                    secret[HEXKEYBYTES+1];
 230         struct key_netstarg     netst;
 231
 232                 if (getsecretkey(fullname, secret, pass) == 0) {
 233                         fprintf(stderr, "Could not find %s's secret key\n",
 234                                 fullname);
 235                         if (sec_domain && *sec_domain &&
 236                                 strcasecmp(sec_domain, local_domain)) {
 237                                 fprintf(stderr,
 238 "The system default domain '%s' is different from the Secure RPC\n\
 239 domain %s where the key is stored.  The Secure RPC domainname is\n\
 240 defined by the directory object stored in the /var/nis/NIS_COLD_START file.\n\
 241 If you need to change this Secure RPC domainname, please use the nisinit(1M)\n\
 242 command with the `-k` option.\n", local_domain, sec_domain);
 243                         } else {
 244                                 fprintf(stderr,
 245                 "Make sure the secret key is stored in domain %s\n",
 246                                 local_domain);
 247                         }
 248                         return (1);
 249                 }
 250
 251                 if (secret[0] == 0) {
 252                         fprintf(stderr, "Password incorrect for %s\n",
 253                                 fullname);
 254                         return (1);
 255                 }
 256                 /* revoke any existing (lingering) credentials... */
 257                 logout_curr_key();
 258
 259                 memcpy(netst.st_priv_key, secret, HEXKEYBYTES);
 260                 memset(secret, 0, HEXKEYBYTES);
 261
 262                 netst.st_pub_key[0] = 0;
 263                 netst.st_netname = strdup(fullname);
 264
 265                 /* do actual key login */
 266                 if (key_setnet(&netst) < 0) {
 267                         fprintf(stderr, "Could not set %s's secret key\n",
 268                                 fullname);
 269                         fprintf(stderr, "May be the keyserv is down?\n");
 270                         if (mkrootkey == 0)   /* nothing else to do */
 271                                 return (1);
 272                 }
 273
 274                 /* write unencrypted secret key into root key file */
 275                 if (mkrootkey)
 276                         write_rootkey(netst.st_priv_key, "des", 192, 0);
 277
 278                 return (0);
 279 }
 280
 281 /*
 282  * Revokes the existing credentials for Secure-RPC and Secure-NFS.
 283  * This should only be called if the user entered the correct password;
 284  * sorta like the way "su" doesn't force a login if you enter the wrong
 285  * password.
 286  */
 287
 288 static void
 289 logout_curr_key()
 290 {
 291         static char             secret[HEXKEYBYTES + 1];
 292         struct nfs_revauth_args nra;
 293
 294         /*
 295          * try to revoke the existing key/credentials, assuming
 296          * one exists.  this will effectively mark "stale" any
 297          * cached credientials...
 298          */
 299         if (key_setsecret(secret) < 0) {
 300                 return;
 301         }
 302
 303         /*
 304          * it looks like a credential already existed, so try and
 305          * revoke any lingering Secure-NFS privledges.
 306          */
 307
 308         nra.authtype = AUTH_DES;
 309         nra.uid = getuid();
 310
 311         (void) _nfssys(NFS_REVAUTH, &nra);
 312 }
 313
 314 void
 315 usage(cmd)
 316         char *cmd;
 317 {
 318         fprintf(stderr, "usage: %s [-r]\n", cmd);
 319         exit(1);
 320 }
 321
 322
 323 int
 324 main(int argc, char *argv[])
 325 {
 326         char            secret[4096];
 327         char            fullname[MAXNETNAMELEN + 1];
 328         char            *getpass();
 329         char            *pass;
 330         int             i = 0;
 331         mechanism_t     **mechlist;
 332
 333         if (argc == 1)
 334                 mkrootkey = 0;
 335         else if (argc == 2 && (strcmp(argv[1], "-r") == 0)) {
 336                 if (geteuid() != 0) {
 337                         fprintf(stderr, "Must be root to use -r option.\n");
 338                         exit(1);
 339                 }
 340                 mkrootkey = 1;
 341         } else
 342                 usage(argv[0]);
 343
 344         if (getnetname(fullname) == 0) {
 345                 fprintf(stderr, "Could not generate netname\n");
 346                 exit(1);
 347         }
 348         sec_domain = strdup(strchr(fullname, '@') + 1);
 349         getdomainname(local_domain, MAXNETNAMELEN);
 350
 351         if (!(pass = getpass("Password:")))
 352                 exit(1);
 353
 354         if (mechlist = __nis_get_mechanisms(FALSE)) {
 355                 while (mechlist[i]) {
 356                         char            *alias;
 357
 358                         if (AUTH_DES_COMPAT_CHK(mechlist[i])) {
 359                                 (void) oldkeylogin(fullname, pass);
 360                                 i++;
 361                                 continue;
 362                         }
 363
 364                         if (VALID_ALIAS(mechlist[i]->alias))
 365                                 alias = mechlist[i]->alias;
 366                         else
 367                                 alias = "";
 368
 369                         if (getsecretkey_g(fullname, mechlist[i]->keylen,
 370                                                 mechlist[i]->algtype, secret,
 371                                                 (((mechlist[i]->keylen / 7) +
 372                                                 8) * 2) + 1, pass) == 0) {
 373                                 fprintf(stderr,
 374                                 "WARNING: Could not find %s's %s secret key\n",
 375                                         fullname, alias);
 376                                 i++;
 377                                 continue;
 378                         }
 379
 380                         if (secret[0] == 0) {
 381                                 fprintf(stderr,
 382                                     "Password incorrect for %s's %s key.\n",
 383                                         fullname, alias);
 384                                 i++;
 385                                 continue;
 386                         }
 387
 388                         if (key_setnet_g(fullname, secret,
 389                                                 mechlist[i]->keylen, NULL, 0,
 390                                                 mechlist[i]->algtype) < 0) {
 391                                 fprintf(stderr,
 392                                 "Could not set %s's %s secret key\n",
 393                                         fullname, alias);
 394                                 fprintf(stderr,
 395                                         "May be the keyserv is down?\n");
 396                                 exit(1);
 397                         }
 398
 399                         if (mkrootkey)
 400                                 write_rootkey(secret, mechlist[i]->alias,
 401                                                 mechlist[i]->keylen,
 402                                                 mechlist[i]->algtype);
 403                         i++;
 404                 }
 405         } else
 406                 exit(oldkeylogin(fullname, pass));
 407
 408         return (0);
 409 }