postinst.mm

   1 #include "CyteKit/UCPlatform.h"
   2
   3 #include <dirent.h>
   4 #include <strings.h>
   5
   6 #include <sys/stat.h>
   7 #include <sys/sysctl.h>
   8 #include <sys/types.h>
   9
  10 #include <Menes/ObjectHandle.h>
  11
  12 void Finish(const char *finish) {
  13     if (finish == NULL)
  14         return;
  15
  16     const char *cydia(getenv("CYDIA"));
  17     if (cydia == NULL)
  18         return;
  19
  20     int fd([[[[NSString stringWithUTF8String:cydia] componentsSeparatedByString:@" "] objectAtIndex:0] intValue]);
  21
  22     FILE *fout(fdopen(fd, "w"));
  23     fprintf(fout, "finish:%s\n", finish);
  24     fclose(fout);
  25 }
  26
  27 static bool setnsfpn(const char *path) {
  28     return system([[NSString stringWithFormat:@"/usr/libexec/cydia/setnsfpn %s", path] UTF8String]) == 0;
  29 }
  30
  31 enum StashStatus {
  32     StashDone,
  33     StashFail,
  34     StashGood,
  35 };
  36
  37 static StashStatus MoveStash() {
  38     struct stat stat;
  39
  40     if (lstat("/var/stash", &stat) == -1)
  41         return errno == ENOENT ? StashGood : StashFail;
  42     else if (S_ISLNK(stat.st_mode))
  43         return StashGood;
  44     else if (!S_ISDIR(stat.st_mode))
  45         return StashFail;
  46
  47     if (lstat("/var/db/stash", &stat) == -1) {
  48         if (errno == ENOENT)
  49             goto move;
  50         else return StashFail;
  51     } else if (S_ISLNK(stat.st_mode))
  52         // XXX: this is fixable
  53         return StashFail;
  54     else if (!S_ISDIR(stat.st_mode))
  55         return StashFail;
  56     else {
  57         if (!setnsfpn("/var/db/stash"))
  58             return StashFail;
  59         if (system("mv -t /var/stash /var/db/stash/*") != 0)
  60             return StashFail;
  61         if (rmdir("/var/db/stash") == -1)
  62             return StashFail;
  63     } move:
  64
  65     if (!setnsfpn("/var/stash"))
  66         return StashFail;
  67
  68     if (rename("/var/stash", "/var/db/stash") == -1)
  69         return StashFail;
  70     if (symlink("/var/db/stash", "/var/stash") != -1)
  71         return StashDone;
  72     if (rename("/var/db/stash", "/var/stash") != -1)
  73         return StashFail;
  74
  75     fprintf(stderr, "/var/stash misplaced -- DO NOT REBOOT\n");
  76     return StashFail;
  77 }
  78
  79 static bool FixProtections() {
  80     const char *path("/var/lib");
  81     mkdir(path, 0755);
  82     if (!setnsfpn(path)) {
  83         fprintf(stderr, "failed to setnsfpn %s\n", path);
  84         return false;
  85     }
  86
  87     return true;
  88 }
  89
  90 static void FixPermissions() {
  91     DIR *stash(opendir("/var/stash"));
  92     if (stash == NULL)
  93         return;
  94
  95     while (dirent *entry = readdir(stash)) {
  96         const char *folder(entry->d_name);
  97         if (strlen(folder) != 8)
  98             continue;
  99         if (strncmp(folder, "_.", 2) != 0)
 100             continue;
 101
 102         char path[1024];
 103         sprintf(path, "/var/stash/%s", folder);
 104
 105         struct stat stat;
 106         if (lstat(path, &stat) == -1)
 107             continue;
 108         if (!S_ISDIR(stat.st_mode))
 109             continue;
 110
 111         chmod(path, 0755);
 112     }
 113
 114     closedir(stash);
 115 }
 116
 117 #define APPLICATIONS "/Applications"
 118 static bool FixApplications() {
 119     char target[1024];
 120     ssize_t length(readlink(APPLICATIONS, target, sizeof(target)));
 121     if (length == -1)
 122         return false;
 123
 124     if (length >= sizeof(target)) // >= "just in case" (I'm nervous)
 125         return false;
 126     target[length] = '\0';
 127
 128     if (strlen(target) != 30)
 129         return false;
 130     if (memcmp(target, "/var/stash/Applications.", 24) != 0)
 131         return false;
 132     if (strchr(target + 24, '/') != NULL)
 133         return false;
 134
 135     struct stat stat;
 136     if (lstat(target, &stat) == -1)
 137         return false;
 138     if (!S_ISDIR(stat.st_mode))
 139         return false;
 140
 141     char temp[] = "/var/stash/_.XXXXXX";
 142     if (mkdtemp(temp) == NULL)
 143         return false;
 144
 145     if (false) undo: {
 146         unlink(temp);
 147         return false;
 148     }
 149
 150     if (chmod(temp, 0755) == -1)
 151         goto undo;
 152
 153     char destiny[strlen(temp) + 32];
 154     sprintf(destiny, "%s%s", temp, APPLICATIONS);
 155
 156     if (unlink(APPLICATIONS) == -1)
 157         goto undo;
 158
 159     if (rename(target, destiny) == -1) {
 160         if (symlink(target, APPLICATIONS) == -1)
 161             fprintf(stderr, "/Applications damaged -- DO NOT REBOOT\n");
 162         goto undo;
 163     } else {
 164         bool success;
 165         if (symlink(destiny, APPLICATIONS) != -1)
 166             success = true;
 167         else {
 168             fprintf(stderr, "/var/stash/Applications damaged -- DO NOT REBOOT\n");
 169             success = false;
 170         }
 171
 172         // unneccessary, but feels better (I'm nervous)
 173         symlink(destiny, target);
 174
 175         [@APPLICATIONS writeToFile:[NSString stringWithFormat:@"%s.lnk", temp] atomically:YES encoding:NSNonLossyASCIIStringEncoding error:NULL];
 176         return success;
 177     }
 178 }
 179
 180 int main(int argc, const char *argv[]) {
 181     if (argc < 2 || strcmp(argv[1], "configure") != 0)
 182         return 0;
 183
 184     NSAutoreleasePool *pool([[NSAutoreleasePool alloc] init]);
 185
 186     bool restart(false);
 187
 188     if (kCFCoreFoundationVersionNumber >= 1000) {
 189         if (!FixProtections())
 190             return 1;
 191         switch (MoveStash()) {
 192             case StashDone:
 193                 restart = true;
 194                 break;
 195             case StashFail:
 196                 fprintf(stderr, "failed to move stash\n");
 197                 return 1;
 198             case StashGood:
 199                 break;
 200         }
 201     }
 202
 203     #define OldCache_ "/var/root/Library/Caches/com.saurik.Cydia"
 204     if (access(OldCache_, F_OK) == 0)
 205         system("rm -rf " OldCache_);
 206
 207     #define NewCache_ "/var/mobile/Library/Caches/com.saurik.Cydia"
 208     system("cd /; su -c 'mkdir -p " NewCache_ "' mobile");
 209     if (access(NewCache_ "/lists", F_OK) != 0 && errno == ENOENT)
 210         system("cp -at " NewCache_ " /var/lib/apt/lists");
 211     system("chown -R 501.501 " NewCache_);
 212
 213     #define OldLibrary_ "/var/lib/cydia"
 214
 215     #define NewLibrary_ "/var/mobile/Library/Cydia"
 216     system("cd /; su -c 'mkdir -p " NewLibrary_ "' mobile");
 217
 218     #define Cytore_ "/metadata.cb0"
 219
 220     #define CYDIA_LIST "/etc/apt/sources.list.d/cydia.list"
 221     unlink(CYDIA_LIST);
 222     [[NSString stringWithFormat:@
 223         "deb http://apt.saurik.com/ ios/%.2f main\n"
 224         "deb http://apt.thebigboss.org/repofiles/cydia/ stable main\n"
 225         "deb http://cydia.zodttd.com/repo/cydia/ stable main\n"
 226         "deb http://apt.modmyi.com/ stable main\n"
 227     , kCFCoreFoundationVersionNumber] writeToFile:@ CYDIA_LIST atomically:YES];
 228
 229     if (access(NewLibrary_ Cytore_, F_OK) != 0 && errno == ENOENT) {
 230         if (access(NewCache_ Cytore_, F_OK) == 0)
 231             system("mv -f " NewCache_ Cytore_ " " NewLibrary_);
 232         else if (access(OldLibrary_ Cytore_, F_OK) == 0)
 233             system("mv -f " OldLibrary_ Cytore_ " " NewLibrary_);
 234         chown(NewLibrary_ Cytore_, 501, 501);
 235     }
 236
 237     FixPermissions();
 238
 239     restart |= FixApplications();
 240
 241     if (restart)
 242         Finish("restart");
 243
 244     [pool release];
 245     return 0;
 246 }