improve: APatch detection; fix: Magisk detection and Magisk manager detection; fix: fd leak

This commit both improves the APatch detection, making it more stricter, and fixes Magisk detection, together with its manager detection, allowing it to successfully boot. Also fixes a fd leak which makes it better at a long run.

zygiskd/src/root_impl/apatch.c

@@ -12,12 +12,28 @@
 enum RootImplState apatch_get_existence(void) {
   struct stat s;
   if (stat("/data/adb/apd", &s) != 0) {
-    if (errno != ENOENT) LOGE("Failed to stat APatch apd binary: %s\n", strerror(errno));
+    if (errno != ENOENT) {
+      LOGE("Failed to stat APatch apd binary: %s\n", strerror(errno));
+    }
     errno = 0;
 
     return Inexistent;
   }
 
+  char *PATH = getenv("PATH");
+  if (PATH == NULL) {
+    LOGE("Failed to get PATH environment variable: %s\n", strerror(errno));
+    errno = 0;
+
+    return Inexistent;
+  }
+
+  if (strstr(PATH, "/data/adb/ap/bin") == NULL) {
+    LOGE("APatch's APD binary is not in PATH\n");
+
+    return Inexistent;
+  }
+
   char apatch_version[32];
   char *const argv[] = { "apd", "-V", NULL };
 
@@ -30,8 +46,6 @@ enum RootImplState apatch_get_existence(void) {
 
   int version = atoi(apatch_version + strlen("apd "));
 
-  LOGI("Meow-- Version: %d\n", version);
-
   if (version == 0) return Abnormal;
   if (version >= MIN_APATCH_VERSION && version <= 999999) return Supported;
   if (version >= 1 && version <= MIN_APATCH_VERSION - 1) return TooOld;

zygiskd/src/root_impl/magisk.c

@@ -22,45 +22,96 @@ char *magisk_managers[] = {
   "io.github.huskydg.magisk"
 };
 
+#define SBIN_MAGISK lp_select("/sbin/magisk32", "/sbin/magisk64")
+#define DEBUG_RAMDISK_MAGISK lp_select("/debug_ramdisk/magisk32", "/debug_ramdisk/magisk64")
+#define BITLESS_DEBUG_RAMDISK_MAGISK "/debug_ramdisk/magisk"
+
 enum magisk_variants variant = Official;
+/* INFO: Longest path */
+static char path_to_magisk[sizeof(DEBUG_RAMDISK_MAGISK)];
 
 enum RootImplState magisk_get_existence(void) {
-  char *argv[] = { "magisk", "-v", NULL };
+  struct stat s;
-
+  if (stat(SBIN_MAGISK, &s) != 0) {
-  char magisk_info[32];
+    LOGE("Failed to stat Magisk /sbin/magisk binary: %s\n", strerror(errno));
-  if (!exec_command(magisk_info, sizeof(magisk_info), "/sbin/magisk", argv)) {
+  
-    LOGE("Failed to execute magisk binary: %s\n", strerror(errno));
+    if (errno != ENOENT) {
+      LOGE("Failed to stat Magisk /sbin/magisk binary: %s\n", strerror(errno));
+    }
     errno = 0;
 
-    return Inexistent;
+    if (stat(DEBUG_RAMDISK_MAGISK, &s) != 0) {
+      LOGE("Failed to stat Magisk %s binary: %s\n", DEBUG_RAMDISK_MAGISK, strerror(errno));
+    
+      if (errno != ENOENT) {
+        LOGE("Failed to stat Magisk %s binary: %s\n", DEBUG_RAMDISK_MAGISK, strerror(errno));
+      }
+      errno = 0;
+
+      if (stat(BITLESS_DEBUG_RAMDISK_MAGISK, &s) != 0) {
+        LOGE("Failed to stat Magisk %s binary: %s\n", BITLESS_DEBUG_RAMDISK_MAGISK, strerror(errno));
+    
+        if (errno != ENOENT) {
+          LOGE("Failed to stat Magisk /debug_ramdisk/magisk binary: %s\n", strerror(errno));
+        }
+        errno = 0;
+
+        return Inexistent;
+      }
+
+      /* INFO: /debug_ramdisk/magisk64 (or 32) doesn't exist but /debug_ramdisk/magisk does */
+      strcpy(path_to_magisk, BITLESS_DEBUG_RAMDISK_MAGISK);
+    } else {
+      /* INFO: /sbin/magisk doesn't exist but /debug_ramdisk/magisk does */
+      strcpy(path_to_magisk, DEBUG_RAMDISK_MAGISK);
+    }
+  } else {
+    /* INFO: /sbin/magisk exists */
+    strcpy(path_to_magisk, SBIN_MAGISK);
   }
 
-  for (unsigned long i = 0; i < sizeof(supported_variants) / sizeof(char *); i++) {
+  char *argv[] = { "magisk", "-v", NULL };
-    if (strstr(magisk_info, supported_variants[i])) variant = (enum magisk_variants)(i + 1);
-  }
 
-  argv[1] = "-V";
+  char magisk_info[128];
-
+  if (!exec_command(magisk_info, sizeof(magisk_info), (const char *)path_to_magisk, argv)) {
-  char magisk_version[32];
-  if (!exec_command(magisk_version, sizeof(magisk_version), "/sbin/magisk", argv)) {
     LOGE("Failed to execute magisk binary: %s\n", strerror(errno));
     errno = 0;
 
     return Abnormal;
   }
 
+  LOGI("Magisk info: %s\n", magisk_info);
+
+  for (unsigned long i = 0; i < sizeof(supported_variants) / sizeof(supported_variants[0]); i++) {
+    if (strstr(magisk_info, supported_variants[i])) variant = (enum magisk_variants)(i + 1);
+  }
+
+  argv[1] = "-V";
+
+  char magisk_version[32];
+  if (!exec_command(magisk_version, sizeof(magisk_version), (const char *)path_to_magisk, argv)) {
+    LOGE("Failed to execute magisk binary: %s\n", strerror(errno));
+    errno = 0;
+
+    return Abnormal;
+  }
+
+  LOGI("Magisk version: %s\n", magisk_version);
+
   if (atoi(magisk_version) >= MIN_MAGISK_VERSION) return Supported;
   else return TooOld;
 }
 
 bool magisk_uid_granted_root(uid_t uid) {
+  LOGI("Checking if UID %d is granted root access\n", uid);
+
   char sqlite_cmd[256];
   snprintf(sqlite_cmd, sizeof(sqlite_cmd), "select 1 from policies where uid=%d and policy=2 limit 1", uid);
 
   char *const argv[] = { "magisk", "--sqlite", sqlite_cmd, NULL };
 
   char result[32];
-  if (!exec_command(result, sizeof(result), "/sbin/magisk", argv)) {
+  if (!exec_command(result, sizeof(result), (const char *)path_to_magisk, argv)) {
     LOGE("Failed to execute magisk binary: %s\n", strerror(errno));
     errno = 0;
 
@@ -71,6 +122,8 @@ bool magisk_uid_granted_root(uid_t uid) {
 }
 
 bool magisk_uid_should_umount(uid_t uid) {
+  LOGI("Checking if UID %d should unmount\n", uid);
+
   struct dirent *entry;
   DIR *proc = opendir("/proc");
   if (!proc) {
@@ -130,7 +183,7 @@ bool magisk_uid_should_umount(uid_t uid) {
     char *const argv[] = { "magisk", "--sqlite", sqlite_cmd, NULL };
 
     char result[32];
-    if (!exec_command(result, sizeof(result), "/sbin/magisk", argv)) {
+    if (!exec_command(result, sizeof(result), (const char *)path_to_magisk, argv)) {
       LOGE("Failed to execute magisk binary: %s\n", strerror(errno));
       errno = 0;
 
@@ -144,13 +197,15 @@ bool magisk_uid_should_umount(uid_t uid) {
 }
 
 bool magisk_uid_is_manager(uid_t uid) {
+  LOGI("Checking if UID %d is a Magisk manager\n", uid);
+
   char sqlite_cmd[256];
   snprintf(sqlite_cmd, sizeof(sqlite_cmd), "select value from strings where key=\"requester\" limit 1");
 
   char *const argv[] = { "magisk", "--sqlite", sqlite_cmd, NULL };
 
-  char output[32];
+  char output[128] = { 0 };
-  if (!exec_command(output, sizeof(output), "/sbin/magisk", argv)) {
+  if (!exec_command(output, sizeof(output), (const char *)path_to_magisk, argv)) {
     LOGE("Failed to execute magisk binary: %s\n", strerror(errno));
     errno = 0;
 
@@ -172,14 +227,13 @@ bool magisk_uid_is_manager(uid_t uid) {
     return s.st_uid == uid;
   } else {
     char stat_path[PATH_MAX];
-    snprintf(stat_path, sizeof(stat_path), "/data/user_de/0/%s", output + strlen("value="));
+    snprintf(stat_path, sizeof(stat_path), "/data/user_de/0/%s", output + strlen("value=")); /* BUG: ISSUE HERE, OUTPUT IS NOT VALID */
 
     LOGI("Checking |%s|\n", stat_path);
 
     struct stat s;
     if (stat(stat_path, &s) == -1) {
-      LOGE("Failed to stat %s: %s\n", stat_path, strerror(errno));
+      LOGE("Failed to stat %s WHAT %s\n", stat_path, strerror(errno));
-      LOGE("???\n");
       errno = 0;
 
       return false;

zygiskd/src/utils.c

@@ -18,10 +18,6 @@
 
 #include "utils.h"
 
-/* INFO 50ms wait */
-// #define ALLOW_WAIT_ON_DEBUG() usleep(500 * 1000)
-#define ALLOW_WAIT_ON_DEBUG() {}
-
 bool switch_mount_namespace(pid_t pid) {
   char path[PATH_MAX];
   snprintf(path, sizeof(path), "/proc/%d/ns/mnt", pid);
@@ -267,8 +263,6 @@ int gread_fd(int fd) {
 
 #define write_func(type)                    \
   ssize_t write_## type(int fd, type val) { \
-    ALLOW_WAIT_ON_DEBUG();                  \
-                                            \
     return write(fd, &val, sizeof(type));   \
   }
 
@@ -293,8 +287,6 @@ ssize_t write_string(int fd, const char *restrict str) {
   size_t len[1];
   len[0] = strlen(str);
 
-  ALLOW_WAIT_ON_DEBUG();
-
   ssize_t written_bytes = write(fd, &len, sizeof(size_t));
   if (written_bytes != sizeof(size_t)) {
     LOGE("Failed to write string length: Not all bytes were written (%zd != %zu).\n", written_bytes, sizeof(size_t));

zygiskd/src/utils.h

@@ -36,10 +36,6 @@ int chcon(const char *path, const char *restrict context);
 
 int unix_listener_from_path(char *path);
 
-// ssize_t send_fd(int sockfd, int fd);
-
-// int recv_fd(int sockfd);
-
 ssize_t gwrite_fd(int fd, int sendfd);
 
 int gread_fd(int fd);

zygiskd/src/zygiskd.c

@@ -784,6 +784,8 @@ void zygiskd_start(char *restrict argv[]) {
       }
     }
 
+    if (action != RequestCompanionSocket) close(client_fd);
+
     continue;
   }