src/snaprestore.m

   1 #import <Foundation/Foundation.h>
   2 #import <Foundation/NSFileManager.h>
   3 #import <sys/snapshot.h>
   4 #import <getopt.h>
   5
   6 typedef char io_string_t[512];
   7 typedef mach_port_t io_object_t;
   8 typedef io_object_t io_registry_entry_t;
   9 io_registry_entry_t IORegistryEntryFromPath(mach_port_t master, const io_string_t path);
  10 CFTypeRef IORegistryEntryCreateCFProperty(io_registry_entry_t entry, CFStringRef key, CFAllocatorRef allocator, uint32_t options);
  11 kern_return_t IOObjectRelease(io_object_t object);
  12
  13 @interface LSApplicationWorkspace : NSObject
  14 + (id)defaultWorkspace;
  15 - (BOOL)_LSPrivateRebuildApplicationDatabasesForSystemApps:(BOOL)arg1 internal:(BOOL)arg2 user:(BOOL)arg3;
  16 - (BOOL)registerApplicationDictionary:(NSDictionary *)applicationDictionary;
  17 - (BOOL)registerBundleWithInfo:(NSDictionary *)bundleInfo options:(NSDictionary *)options type:(unsigned long long)arg3 progress:(id)arg4 ;
  18 - (BOOL)registerApplication:(NSURL *)url;
  19 - (BOOL)registerPlugin:(NSURL *)url;
  20 - (BOOL)unregisterApplication:(NSURL *)url;
  21 - (NSArray *)installedPlugins;
  22 -(void)_LSPrivateSyncWithMobileInstallation;
  23 @end
  24
  25 void usage(char *name) {
  26         printf(
  27                 "Usage: %s [volume] [snapshot]\n", name);
  28 }
  29
  30 NSString *bootsnapshot() {
  31         const io_registry_entry_t chosen = IORegistryEntryFromPath(0, "IODeviceTree:/chosen");
  32         const NSData *data = (__bridge const NSData *)IORegistryEntryCreateCFProperty(chosen, (__bridge CFStringRef)@"boot-manifest-hash", kCFAllocatorDefault, 0);
  33         IOObjectRelease(chosen);
  34
  35         NSMutableString *manifestHash = [NSMutableString stringWithString:@""];
  36         NSUInteger len = [data length];
  37         Byte *buf = (Byte*)malloc(len);
  38         memcpy(buf, [data bytes], len);
  39         int buf2;
  40         for (buf2 = 0; buf2 <= 19; buf2++) {
  41                 [manifestHash appendFormat:@"%02X", buf[buf2]];
  42         }
  43         // add com.apple.os.update-
  44         return [NSString stringWithFormat:@"%@%@", @"com.apple.os.update-", manifestHash];
  45 }
  46
  47 int restore(const char *vol, const char *snap) {
  48         int fd = open(vol, O_RDONLY, 0);
  49
  50         int ret = fs_snapshot_revert(fd, snap, 0);
  51         return ret;
  52 }
  53
  54 int mount(const char *vol, const char *snap, const char *mnt) {
  55         int fd = open(vol, O_RDONLY, 0);
  56
  57         BOOL isDir;
  58         NSFileManager *fileManager = [NSFileManager defaultManager];
  59                 if(![fileManager fileExistsAtPath:[NSString stringWithUTF8String:mnt] isDirectory:&isDir])
  60                         if(![fileManager createDirectoryAtPath:[NSString stringWithUTF8String:mnt] withIntermediateDirectories:YES attributes:nil error:NULL])
  61                                 NSLog(@"Error: Create folder failed %s", mnt);
  62
  63         int ret = fs_snapshot_mount(fd, mnt, snap, 0);
  64
  65         return ret;
  66 }
  67
  68 NSMutableSet *findApps(const char *root, const char *mnt) {
  69         NSMutableString *rootApplications = [NSMutableString stringWithUTF8String:root];
  70         rootApplications = [[rootApplications stringByAppendingString:@"/Applications"] mutableCopy];
  71
  72         NSMutableString *mntApplications = [NSMutableString stringWithUTF8String:mnt];
  73         mntApplications = [[mntApplications stringByAppendingString:@"/Applications"] mutableCopy];
  74
  75         NSArray *rootApps = [[NSFileManager defaultManager] contentsOfDirectoryAtPath:rootApplications error:nil];
  76         NSArray *mntApps = [[NSFileManager defaultManager] contentsOfDirectoryAtPath:mntApplications error:nil];
  77
  78         NSMutableSet *ret = [[NSMutableSet alloc] init];
  79         for (NSString *app in rootApps) {
  80                 if (![mntApps containsObject:app]) {
  81                         [ret addObject:[@"/Applications/" stringByAppendingString:app]];
  82                 }
  83         }
  84
  85         return ret;
  86 }
  87
  88 int unregisterPath(NSString *path) {
  89         path = [path stringByResolvingSymlinksInPath];
  90         NSURL *url = [NSURL fileURLWithPath:path];
  91         LSApplicationWorkspace *workspace = [LSApplicationWorkspace defaultWorkspace];
  92         return [workspace unregisterApplication:url];
  93 }
  94
  95 int rename(const char *vol, const char *snap) {
  96         int fd = open(vol, O_RDONLY, 0);
  97
  98         int ret = fs_snapshot_rename(fd, snap, [bootsnapshot() UTF8String], 0);
  99         return ret;
 100 }
 101
 102 int clean() {
 103         NSArray *extrafiles = @[@"/var/lib", @"/var/cache"];
 104         NSError *error = nil;
 105         for (NSString *path in extrafiles) {
 106                 [[NSFileManager defaultManager] removeItemAtPath:path error:&error];
 107         }
 108         return 0;
 109 }
 110
 111 int main(int argc, char *argv[]) {
 112         if (argc != 3) {
 113                 usage(argv[0]);
 114                 return 0;
 115         }
 116
 117         char *vol = argv[1];
 118         char *snap = argv[2];
 119         char *mnt = "/tmp/rootfsmnt";
 120
 121         printf("Restoring snapshot %s...\n", snap);
 122         restore(vol, snap);
 123         printf("Restored snapshot...\n");
 124         printf("Mounting rootfs...\n");
 125         mount(vol, snap, mnt);
 126         printf("Mounted %s at %s\n", snap, mnt);
 127         NSMutableSet *appSet = findApps(vol, mnt);
 128         if ([appSet count]) {
 129                 for (NSString *app in appSet) {
 130                         printf("unregistering %s\n", [app UTF8String]);
 131                         unregisterPath(app);
 132                 }
 133         }
 134         printf("Cleaning up /var\n");
 135         clean();
 136         printf("Renaming snapshot...\n");
 137         rename(vol, snap);
 138         printf("Restoring %s on %s has succeeded\n", snap, vol);
 139         return 0;
 140 }