1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include <stdio.h> 18 #include <stdlib.h> 19 #include <fcntl.h> 20 #include <unistd.h> 21 #include <errno.h> 22 #include <string.h> 23 #include <stdlib.h> 24 25 #include <sys/types.h> 26 #include <sys/ioctl.h> 27 #include <sys/stat.h> 28 29 #include <linux/kdev_t.h> 30 31 #define LOG_TAG "Vold" 32 33 #include <cutils/log.h> 34 35 #include <sysutils/SocketClient.h> 36 37 #include "Devmapper.h" 38 39 #define DEVMAPPER_BUFFER_SIZE 4096 40 41 int Devmapper::dumpState(SocketClient *c) { 42 43 char *buffer = (char *) malloc(1024 * 64); 44 if (!buffer) { 45 SLOGE("Error allocating memory (%s)", strerror(errno)); 46 return -1; 47 } 48 memset(buffer, 0, (1024 * 64)); 49 50 char *buffer2 = (char *) malloc(DEVMAPPER_BUFFER_SIZE); 51 if (!buffer2) { 52 SLOGE("Error allocating memory (%s)", strerror(errno)); 53 free(buffer); 54 return -1; 55 } 56 57 int fd; 58 if ((fd = open("/dev/device-mapper", O_RDWR)) < 0) { 59 SLOGE("Error opening devmapper (%s)", strerror(errno)); 60 free(buffer); 61 free(buffer2); 62 return -1; 63 } 64 65 struct dm_ioctl *io = (struct dm_ioctl *) buffer; 66 ioctlInit(io, (1024 * 64), NULL, 0); 67 68 if (ioctl(fd, DM_LIST_DEVICES, io)) { 69 SLOGE("DM_LIST_DEVICES ioctl failed (%s)", strerror(errno)); 70 free(buffer); 71 free(buffer2); 72 close(fd); 73 return -1; 74 } 75 76 struct dm_name_list *n = (struct dm_name_list *) (((char *) buffer) + io->data_start); 77 if (!n->dev) { 78 free(buffer); 79 free(buffer2); 80 close(fd); 81 return 0; 82 } 83 84 unsigned nxt = 0; 85 do { 86 n = (struct dm_name_list *) (((char *) n) + nxt); 87 88 memset(buffer2, 0, DEVMAPPER_BUFFER_SIZE); 89 struct dm_ioctl *io2 = (struct dm_ioctl *) buffer2; 90 ioctlInit(io2, DEVMAPPER_BUFFER_SIZE, n->name, 0); 91 if (ioctl(fd, DM_DEV_STATUS, io2)) { 92 if (errno != ENXIO) { 93 SLOGE("DM_DEV_STATUS ioctl failed (%s)", strerror(errno)); 94 } 95 io2 = NULL; 96 } 97 98 char *tmp; 99 if (!io2) { 100 asprintf(&tmp, "%s %llu:%llu (no status available)", n->name, MAJOR(n->dev), MINOR(n->dev)); 101 } else { 102 asprintf(&tmp, "%s %llu:%llu %d %d 0x%.8x %llu:%llu", n->name, MAJOR(n->dev), 103 MINOR(n->dev), io2->target_count, io2->open_count, io2->flags, MAJOR(io2->dev), 104 MINOR(io2->dev)); 105 } 106 c->sendMsg(0, tmp, false); 107 free(tmp); 108 nxt = n->next; 109 } while (nxt); 110 111 free(buffer); 112 free(buffer2); 113 close(fd); 114 return 0; 115 } 116 117 void Devmapper::ioctlInit(struct dm_ioctl *io, size_t dataSize, 118 const char *name, unsigned flags) { 119 memset(io, 0, dataSize); 120 io->data_size = dataSize; 121 io->data_start = sizeof(struct dm_ioctl); 122 io->version[0] = 4; 123 io->version[1] = 0; 124 io->version[2] = 0; 125 io->flags = flags; 126 if (name) { 127 int ret = strlcpy(io->name, name, sizeof(io->name)); 128 if (ret >= sizeof(io->name)) 129 abort(); 130 } 131 } 132 133 int Devmapper::lookupActive(const char *name, char *ubuffer, size_t len) { 134 char *buffer = (char *) malloc(DEVMAPPER_BUFFER_SIZE); 135 if (!buffer) { 136 SLOGE("Error allocating memory (%s)", strerror(errno)); 137 return -1; 138 } 139 140 int fd; 141 if ((fd = open("/dev/device-mapper", O_RDWR)) < 0) { 142 SLOGE("Error opening devmapper (%s)", strerror(errno)); 143 free(buffer); 144 return -1; 145 } 146 147 struct dm_ioctl *io = (struct dm_ioctl *) buffer; 148 149 ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0); 150 if (ioctl(fd, DM_DEV_STATUS, io)) { 151 if (errno != ENXIO) { 152 SLOGE("DM_DEV_STATUS ioctl failed for lookup (%s)", strerror(errno)); 153 } 154 free(buffer); 155 close(fd); 156 return -1; 157 } 158 close(fd); 159 160 unsigned minor = (io->dev & 0xff) | ((io->dev >> 12) & 0xfff00); 161 free(buffer); 162 snprintf(ubuffer, len, "/dev/block/dm-%u", minor); 163 return 0; 164 } 165 166 int Devmapper::create(const char *name, const char *loopFile, const char *key, 167 unsigned int numSectors, char *ubuffer, size_t len) { 168 char *buffer = (char *) malloc(DEVMAPPER_BUFFER_SIZE); 169 if (!buffer) { 170 SLOGE("Error allocating memory (%s)", strerror(errno)); 171 return -1; 172 } 173 174 int fd; 175 if ((fd = open("/dev/device-mapper", O_RDWR)) < 0) { 176 SLOGE("Error opening devmapper (%s)", strerror(errno)); 177 free(buffer); 178 return -1; 179 } 180 181 struct dm_ioctl *io = (struct dm_ioctl *) buffer; 182 183 // Create the DM device 184 ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0); 185 186 if (ioctl(fd, DM_DEV_CREATE, io)) { 187 SLOGE("Error creating device mapping (%s)", strerror(errno)); 188 free(buffer); 189 close(fd); 190 return -1; 191 } 192 193 // Set the legacy geometry 194 ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0); 195 196 char *geoParams = buffer + sizeof(struct dm_ioctl); 197 // bps=512 spc=8 res=32 nft=2 sec=8190 mid=0xf0 spt=63 hds=64 hid=0 bspf=8 rdcl=2 infs=1 bkbs=2 198 strcpy(geoParams, "0 64 63 0"); 199 geoParams += strlen(geoParams) + 1; 200 geoParams = (char *) _align(geoParams, 8); 201 if (ioctl(fd, DM_DEV_SET_GEOMETRY, io)) { 202 SLOGE("Error setting device geometry (%s)", strerror(errno)); 203 free(buffer); 204 close(fd); 205 return -1; 206 } 207 208 // Retrieve the device number we were allocated 209 ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0); 210 if (ioctl(fd, DM_DEV_STATUS, io)) { 211 SLOGE("Error retrieving devmapper status (%s)", strerror(errno)); 212 free(buffer); 213 close(fd); 214 return -1; 215 } 216 217 unsigned minor = (io->dev & 0xff) | ((io->dev >> 12) & 0xfff00); 218 snprintf(ubuffer, len, "/dev/block/dm-%u", minor); 219 220 // Load the table 221 struct dm_target_spec *tgt; 222 tgt = (struct dm_target_spec *) &buffer[sizeof(struct dm_ioctl)]; 223 224 ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, DM_STATUS_TABLE_FLAG); 225 io->target_count = 1; 226 tgt->status = 0; 227 228 tgt->sector_start = 0; 229 tgt->length = numSectors; 230 231 strlcpy(tgt->target_type, "crypt", sizeof(tgt->target_type)); 232 233 char *cryptParams = buffer + sizeof(struct dm_ioctl) + sizeof(struct dm_target_spec); 234 snprintf(cryptParams, 235 DEVMAPPER_BUFFER_SIZE - (sizeof(struct dm_ioctl) + sizeof(struct dm_target_spec)), 236 "twofish %s 0 %s 0", key, loopFile); 237 cryptParams += strlen(cryptParams) + 1; 238 cryptParams = (char *) _align(cryptParams, 8); 239 tgt->next = cryptParams - buffer; 240 241 if (ioctl(fd, DM_TABLE_LOAD, io)) { 242 SLOGE("Error loading mapping table (%s)", strerror(errno)); 243 free(buffer); 244 close(fd); 245 return -1; 246 } 247 248 // Resume the new table 249 ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0); 250 251 if (ioctl(fd, DM_DEV_SUSPEND, io)) { 252 SLOGE("Error Resuming (%s)", strerror(errno)); 253 free(buffer); 254 close(fd); 255 return -1; 256 } 257 258 free(buffer); 259 260 close(fd); 261 return 0; 262 } 263 264 int Devmapper::destroy(const char *name) { 265 char *buffer = (char *) malloc(DEVMAPPER_BUFFER_SIZE); 266 if (!buffer) { 267 SLOGE("Error allocating memory (%s)", strerror(errno)); 268 return -1; 269 } 270 271 int fd; 272 if ((fd = open("/dev/device-mapper", O_RDWR)) < 0) { 273 SLOGE("Error opening devmapper (%s)", strerror(errno)); 274 free(buffer); 275 return -1; 276 } 277 278 struct dm_ioctl *io = (struct dm_ioctl *) buffer; 279 280 // Create the DM device 281 ioctlInit(io, DEVMAPPER_BUFFER_SIZE, name, 0); 282 283 if (ioctl(fd, DM_DEV_REMOVE, io)) { 284 if (errno != ENXIO) { 285 SLOGE("Error destroying device mapping (%s)", strerror(errno)); 286 } 287 free(buffer); 288 close(fd); 289 return -1; 290 } 291 292 free(buffer); 293 close(fd); 294 return 0; 295 } 296 297 void *Devmapper::_align(void *ptr, unsigned int a) 298 { 299 register unsigned long agn = --a; 300 301 return (void *) (((unsigned long) ptr + agn) & ~agn); 302 } 303
