snapshot.c

   1 /*
   2  * Copyright (C) 2014 John Crispin <blogic@openwrt.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU Lesser General Public License version 2.1
   6  * as published by the Free Software Foundation
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <sys/stat.h>
  15 #include <sys/stat.h>
  16 #include <sys/types.h>
  17 #include <sys/ioctl.h>
  18 #include <sys/mount.h>
  19 #include <mtd/mtd-user.h>
  20
  21 #include <glob.h>
  22 #include <fcntl.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <libgen.h>
  26 #include <unistd.h>
  27 #include <string.h>
  28 #include <inttypes.h>
  29
  30 #include <libubox/list.h>
  31 #include <libubox/blob.h>
  32 #include <libubox/md5.h>
  33 #include <libubox/ulog.h>
  34
  35 #include "libfstools/libfstools.h"
  36 #include "libfstools/volume.h"
  37 #include "libfstools/snapshot.h"
  38
  39 static int
  40 config_write(int argc, char **argv)
  41 {
  42         struct volume *v = volume_find("rootfs_data");
  43         int ret;
  44
  45         if (!v)
  46                 return -1;
  47
  48         ret = volatile_write(v, 0);
  49         if (!ret)
  50                 ret = sentinel_write(v, 0);
  51
  52         return ret;
  53 }
  54
  55 static int
  56 config_read(int argc, char **argv)
  57 {
  58         struct volume *v = volume_find("rootfs_data");
  59         struct file_header conf, sentinel;
  60         int next, block, ret = 0;
  61         uint32_t seq;
  62
  63         if (!v)
  64                 return -1;
  65
  66         block = config_find(v, &conf, &sentinel);
  67         next = snapshot_next_free(v, &seq);
  68         if (is_config(&conf) && conf.seq == seq)
  69                 block = next;
  70         else if (!is_config(&sentinel) || sentinel.seq != seq)
  71                 return -1;
  72
  73         unlink("/tmp/config.tar.gz");
  74         ret = snapshot_read_file(v, block, "/tmp/config.tar.gz", CONF);
  75
  76         if (ret < 1)
  77                 ULOG_ERR("failed to read /tmp/config.tar.gz\n");
  78
  79         return ret;
  80 }
  81
  82 static int
  83 snapshot_write(int argc, char **argv)
  84 {
  85         struct volume *v = volume_find("rootfs_data");
  86         int block, ret;
  87         uint32_t seq;
  88
  89         if (!v)
  90                 return -1;
  91
  92         block = snapshot_next_free(v, &seq);
  93         if (block < 0)
  94                 block = 0;
  95
  96         ret = snapshot_write_file(v, block, "/tmp/snapshot.tar.gz", seq + 1, DATA);
  97         if (ret)
  98                 ULOG_ERR("failed to write /tmp/snapshot.tar.gz\n");
  99         else
 100                 ULOG_INFO("wrote /tmp/snapshot.tar.gz\n");
 101
 102         return ret;
 103 }
 104
 105 static int
 106 snapshot_mark(int argc, char **argv)
 107 {
 108         __be32 owrt = cpu_to_be32(OWRT);
 109         struct volume *v;
 110         size_t sz;
 111         int fd;
 112
 113         ULOG_WARN("This will remove all snapshot data stored on the system. Are you sure? [N/y]\n");
 114         if (getchar() != 'y')
 115                 return -1;
 116
 117         v = volume_find("rootfs_data");
 118         if (!v) {
 119                 ULOG_ERR("MTD partition 'rootfs_data' not found\n");
 120                 return -1;
 121         }
 122
 123         fd = open(v->blk, O_WRONLY);
 124         ULOG_INFO("%s - marking with 0x%08x\n", v->blk, owrt);
 125         if (fd < 0) {
 126                 ULOG_ERR("opening %s failed\n", v->blk);
 127                 return -1;
 128         }
 129
 130         sz = write(fd, &owrt, sizeof(owrt));
 131         close(fd);
 132
 133         if (sz != 1) {
 134                 ULOG_ERR("writing %s failed: %s\n", v->blk, strerror(errno));
 135                 return -1;
 136         }
 137
 138         return 0;
 139 }
 140
 141 static int
 142 snapshot_read(int argc, char **argv)
 143 {
 144         struct volume *v = volume_find("rootfs_data");;
 145         int block = 0, ret = 0;
 146         char file[64];
 147
 148         if (!v)
 149                 return -1;
 150
 151         if (argc > 2) {
 152                 block = atoi(argv[2]);
 153                 if (block >= (v->size / v->block_size)) {
 154                         ULOG_ERR("invalid block %d > %" PRIu64 "\n",
 155                                  block, (uint64_t) v->size / v->block_size);
 156                         goto out;
 157                 }
 158                 snprintf(file, sizeof(file), "/tmp/snapshot/block%d.tar.gz", block);
 159
 160                 ret = snapshot_read_file(v, block, file, DATA);
 161                 goto out;
 162         }
 163
 164         do {
 165                 snprintf(file, sizeof(file), "/tmp/snapshot/block%d.tar.gz", block);
 166                 block = snapshot_read_file(v, block, file, DATA);
 167         } while (block > 0);
 168
 169 out:
 170         return ret;
 171 }
 172
 173 static int
 174 snapshot_info(void)
 175 {
 176         struct volume *v = volume_find("rootfs_data");
 177         struct file_header hdr = { 0 }, conf;
 178         int block = 0;
 179
 180         if (!v)
 181                 return -1;
 182
 183         ULOG_INFO("sectors:\t%" PRIu64 ", block_size:\t%dK\n",
 184                   (uint64_t) v->size / v->block_size, v->block_size / 1024);
 185         do {
 186                 if (volume_read(v, &hdr, block * v->block_size, sizeof(struct file_header))) {
 187                         ULOG_ERR("scanning for next free block failed\n");
 188                         return 0;
 189                 }
 190
 191                 be32_to_hdr(&hdr);
 192
 193                 if (hdr.magic != OWRT)
 194                         break;
 195
 196                 if (hdr.type == DATA)
 197                         ULOG_INFO("block %d:\tsnapshot entry, size: %d, sectors: %d, sequence: %d\n", block,  hdr.length, pad_file_size(v, hdr.length) / v->block_size, hdr.seq);
 198                 else if (hdr.type == CONF)
 199                         ULOG_INFO("block %d:\tvolatile entry, size: %d, sectors: %d, sequence: %d\n", block,  hdr.length, pad_file_size(v, hdr.length) / v->block_size, hdr.seq);
 200
 201                 if (hdr.type == DATA && !valid_file_size(hdr.length))
 202                         block += pad_file_size(v, hdr.length) / v->block_size;
 203         } while (hdr.type == DATA);
 204         block = config_find(v, &conf, &hdr);
 205         if (block > 0)
 206                 ULOG_INFO("block %d:\tsentinel entry, size: %d, sectors: %d, sequence: %d\n", block, hdr.length, pad_file_size(v, hdr.length) / v->block_size, hdr.seq);
 207
 208         return 0;
 209 }
 210
 211 int main(int argc, char **argv)
 212 {
 213         if (argc < 2)
 214                 return -1;
 215
 216         if (!strcmp(argv[1], "config_read"))
 217                 return config_read(argc, argv);
 218         if (!strcmp(argv[1], "config_write"))
 219                 return config_write(argc, argv);
 220         if (!strcmp(argv[1], "read"))
 221                 return snapshot_read(argc, argv);
 222         if (!strcmp(argv[1], "write"))
 223                 return snapshot_write(argc, argv);
 224         if (!strcmp(argv[1], "mark"))
 225                 return snapshot_mark(argc, argv);
 226         if (!strcmp(argv[1], "info"))
 227                 return snapshot_info();
 228         return -1;
 229 }