mount_umap.c revision 1.4
1 /* $NetBSD: mount_umap.c,v 1.4 1995/04/24 13:23:11 cgd Exp $ */ 2 3 /* 4 * Copyright (c) 1992, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software donated to Berkeley by 8 * Jan-Simon Pendry. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #ifndef lint 40 char copyright[] = 41 "@(#) Copyright (c) 1992, 1993, 1994\n\ 42 The Regents of the University of California. All rights reserved.\n"; 43 #endif /* not lint */ 44 45 #ifndef lint 46 #if 0 47 static char sccsid[] = "@(#)mount_umap.c 8.3 (Berkeley) 3/27/94"; 48 #else 49 static char rcsid[] = "$NetBSD: mount_umap.c,v 1.4 1995/04/24 13:23:11 cgd Exp $"; 50 #endif 51 #endif /* not lint */ 52 53 #include <sys/param.h> 54 #include <sys/mount.h> 55 #include <sys/stat.h> 56 57 #include <miscfs/umapfs/umap.h> 58 59 #include <err.h> 60 #include <stdio.h> 61 #include <stdlib.h> 62 #include <string.h> 63 #include <unistd.h> 64 65 #include "mntopts.h" 66 67 #define ROOTUSER 0 68 /* 69 * This define controls whether any user but the superuser can own and 70 * write mapfiles. If other users can, system security can be gravely 71 * compromised. If this is not a concern, undefine SECURITY. 72 */ 73 #define MAPSECURITY 1 74 75 /* 76 * This routine provides the user interface to mounting a umap layer. 77 * It takes 4 mandatory parameters. The mandatory arguments are the place 78 * where the next lower level is mounted, the place where the umap layer is to 79 * be mounted, the name of the user mapfile, and the name of the group 80 * mapfile. The routine checks the ownerships and permissions on the 81 * mapfiles, then opens and reads them. Then it calls mount(), which 82 * will, in turn, call the umap version of mount. 83 */ 84 85 struct mntopt mopts[] = { 86 MOPT_STDOPTS, 87 { NULL } 88 }; 89 90 void usage __P((void)); 91 92 int 93 main(argc, argv) 94 int argc; 95 char *argv[]; 96 { 97 static char not[] = "; not mounted."; 98 struct stat statbuf; 99 struct umap_args args; 100 FILE *fp, *gfp; 101 long d1, d2; 102 u_long mapdata[MAPFILEENTRIES][2]; 103 u_long gmapdata[GMAPFILEENTRIES][2]; 104 int ch, count, gnentries, mntflags, nentries; 105 char *gmapfile, *mapfile, *source, *target, buf[20]; 106 107 mntflags = 0; 108 mapfile = gmapfile = NULL; 109 while ((ch = getopt(argc, argv, "g:o:u:")) != EOF) 110 switch (ch) { 111 case 'g': 112 gmapfile = optarg; 113 break; 114 case 'o': 115 getmntopts(optarg, mopts, &mntflags); 116 break; 117 case 'u': 118 mapfile = optarg; 119 break; 120 case '?': 121 default: 122 usage(); 123 } 124 argc -= optind; 125 argv += optind; 126 127 if (argc != 2 || mapfile == NULL || gmapfile == NULL) 128 usage(); 129 130 source = argv[0]; 131 target = argv[1]; 132 133 /* Read in uid mapping data. */ 134 if ((fp = fopen(mapfile, "r")) == NULL) 135 err(1, "%s%s", mapfile, not); 136 137 #ifdef MAPSECURITY 138 /* 139 * Check that group and other don't have write permissions on 140 * this mapfile, and that the mapfile belongs to root. 141 */ 142 if (fstat(fileno(fp), &statbuf)) 143 err(1, "%s%s", mapfile, not); 144 if (statbuf.st_mode & S_IWGRP || statbuf.st_mode & S_IWOTH) { 145 strmode(statbuf.st_mode, buf); 146 err(1, "%s: improper write permissions (%s)%s", 147 mapfile, buf, not); 148 } 149 if (statbuf.st_uid != ROOTUSER) 150 errx(1, "%s does not belong to root%s", mapfile, not); 151 #endif /* MAPSECURITY */ 152 153 if ((fscanf(fp, "%d\n", &nentries)) != 1) 154 errx(1, "%s: nentries not found%s", mapfile, not); 155 if (nentries > MAPFILEENTRIES) 156 errx(1, 157 "maximum number of entries is %d%s", MAPFILEENTRIES, not); 158 #if 0 159 (void)printf("reading %d entries\n", nentries); 160 #endif 161 for (count = 0; count < nentries; ++count) { 162 if ((fscanf(fp, "%lu %lu\n", &d1, &d2)) != 2) { 163 if (ferror(fp)) 164 err(1, "%s%s", mapfile, not); 165 if (feof(fp)) 166 errx(1, "%s: unexpected end-of-file%s", 167 mapfile, not); 168 errx(1, "%s: illegal format (line %d)%s", 169 mapfile, count + 2, not); 170 } 171 mapdata[count][0] = d1; 172 mapdata[count][1] = d2; 173 #if 0 174 /* Fix a security hole. */ 175 if (mapdata[count][1] == 0) 176 errx(1, "mapping id 0 not permitted (line %d)%s", 177 count + 2, not); 178 #endif 179 } 180 181 /* Read in gid mapping data. */ 182 if ((gfp = fopen(gmapfile, "r")) == NULL) 183 err(1, "%s%s", gmapfile, not); 184 185 #ifdef MAPSECURITY 186 /* 187 * Check that group and other don't have write permissions on 188 * this group mapfile, and that the file belongs to root. 189 */ 190 if (fstat(fileno(gfp), &statbuf)) 191 err(1, "%s%s", gmapfile, not); 192 if (statbuf.st_mode & S_IWGRP || statbuf.st_mode & S_IWOTH) { 193 strmode(statbuf.st_mode, buf); 194 err(1, "%s: improper write permissions (%s)%s", 195 gmapfile, buf, not); 196 } 197 if (statbuf.st_uid != ROOTUSER) 198 errx(1, "%s does not belong to root%s", gmapfile, not); 199 #endif /* MAPSECURITY */ 200 201 if ((fscanf(gfp, "%d\n", &gnentries)) != 1) 202 errx(1, "nentries not found%s", gmapfile, not); 203 if (gnentries > MAPFILEENTRIES) 204 errx(1, 205 "maximum number of entries is %d%s", GMAPFILEENTRIES, not); 206 #if 0 207 (void)printf("reading %d group entries\n", gnentries); 208 #endif 209 210 for (count = 0; count < gnentries; ++count) { 211 if ((fscanf(gfp, "%lu %lu\n", &d1, &d2)) != 2) { 212 if (ferror(gfp)) 213 err(1, "%s%s", gmapfile, not); 214 if (feof(gfp)) 215 errx(1, "%s: unexpected end-of-file%s", 216 gmapfile, not); 217 errx(1, "%s: illegal format (line %d)%s", 218 gmapfile, count + 2, not); 219 } 220 gmapdata[count][0] = d1; 221 gmapdata[count][1] = d2; 222 } 223 224 225 /* Setup mount call args. */ 226 args.target = source; 227 args.nentries = nentries; 228 args.mapdata = mapdata; 229 args.gnentries = gnentries; 230 args.gmapdata = gmapdata; 231 232 if (mount(MOUNT_UMAP, argv[1], mntflags, &args)) 233 err(1, NULL); 234 exit(0); 235 } 236 237 void 238 usage() 239 { 240 (void)fprintf(stderr, 241 "usage: mount_umap [-o options] -u usermap -g groupmap target_fs mount_point\n"); 242 exit(1); 243 } 244
Indexes created Tue Oct 14 15:09:51 GMT 2025