add: base for C99 zygiskd

This commit adds the first base for C99 zygiskd, that is not fully working or code-ready.

zygiskd-new/.gitignore

@@ -0,0 +1,2 @@
+zygiskd64
+zygiskd32

zygiskd-new/Makefile

@@ -0,0 +1,33 @@
+CC := ~/Android/Sdk/ndk/27.0.11902837/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android34-clang
+
+# FILES = root_impl/common.c   \
+#         root_impl/kernelsu.c \
+# 				companion.c          \
+# 				dl.c                 \
+# 				main.c               \
+# 				utils.c              \
+# 				zygiskd.c
+
+FILES = root_impl/*.c \
+        *.c
+
+CFLAGS = -D_GNU_SOURCE -std=c99 -Wpedantic -Wall -Wextra -Werror -Wformat -Wuninitialized -Wshadow -Wno-zero-length-array -Wno-fixed-enum-extension -Iroot_impl -llog
+
+all: CFLAGS += -DDEBUG=0 -O3 -flto=thin -Wl,--strip-all
+all:
+	$(CC) $(CFLAGS) $(FILES) -o zygiskd64
+
+debug: CFLAGS += -DDEBUG=1 -g -O0
+debug:
+	$(CC) $(CFLAGS) $(FILES) -o zygiskd64
+
+32bit: CFLAGS += -m32 -DDEBUG=0 -O3 -flto=thin -Wl,--strip-all
+32bit:
+	$(CC) $(CFLAGS) $(FILES) -o zygiskd32
+
+32bit-debug: CFLAGS += -m32 -DDEBUG=1 -g -O0
+32bit-debug:
+	$(CC) $(CFLAGS) $(FILES) -o zygiskd32
+
+clean:
+	rm -f zygiskd

zygiskd-new/companion.c

@@ -0,0 +1,130 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <dlfcn.h>
+#include <errno.h>
+
+#include <unistd.h>
+#include <linux/limits.h>
+#include <pthread.h>
+
+#include <android/log.h>
+
+#include "companion.h"
+#include "dl.h"
+#include "utils.h"
+
+typedef void (*ZygiskCompanionEntryFn)(int);
+
+ZygiskCompanionEntryFn load_module(int fd) {
+  char path[PATH_MAX];
+  snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);
+
+  void *handle = android_dlopen(path, RTLD_NOW);
+  void *entry = dlsym(handle, "zygisk_companion_entry");
+  if (entry == NULL) return NULL;
+
+  return (ZygiskCompanionEntryFn)entry;
+}
+
+void *ExecuteNew(void *arg) {
+  int fd = *((int *)arg);
+
+  struct stat st0;
+  if (fstat(fd, &st0) == -1) {
+    LOGE("Failed to stat client fd\n");
+
+    free(arg);
+
+    exit(0);
+  }
+  entry(fd);
+
+  // Only close client if it is the same file so we don't
+  // accidentally close a re-used file descriptor.
+  // This check is required because the module companion
+  // handler could've closed the file descriptor already.
+  struct stat st1;
+  if (fstat(fd, &st1) == -1) {
+    LOGE("Failed to stat client fd\n");
+
+    free(arg);
+
+    exit(0);
+  }
+
+  if (st0.st_dev != st1.st_dev || st0.st_ino != st1.st_ino) {
+    close(fd);
+  }
+
+  free(arg);
+
+  return NULL;
+}
+
+
+void entry(int fd) {
+  LOGI("Previous error (2): %s\n", strerror(errno));
+
+  LOGI("companion entry fd: |%d|\n", fd);
+
+  LOGI("Reading name length\n");
+
+  char name[256 + 1];
+  LOGI("Previous error(6): %s\n", strerror(errno));
+
+  /* INFO: Getting stuck here */
+  ssize_t ret = read_string(fd, name, sizeof(name) - 1);
+  if (ret == -1) return;
+
+  name[ret] = '\0';
+
+  LOGI("Companion process requested for `%s`\n", name);
+
+  // int library_fd;
+  // recv_fd(fd, &library_fd);
+
+  // LOGI("Library fd: %d\n", library_fd);
+
+  // ZygiskCompanionEntryFn entry = load_module(library_fd);
+
+  // LOGI("Library loaded\n");
+
+  // close(library_fd);
+
+  // LOGI("Library closed\n");
+
+  // if (entry == NULL) {
+  //   LOGI("No companion entry for: %s\n", name);
+
+  //   write(fd, (void *)0, 1);
+
+  //   return;
+  // }
+
+  // LOGI("Companion process created for: %s\n", name);
+
+  // write(fd, (void *)1, 1);
+
+  // while (1) {
+  //   int client_fd;
+  //   recv_fd(fd, &client_fd);
+
+  //   LOGI("New companion request from module \"%s\" with fd \"%d\"\n", name, client_fd);
+
+  //   int response = 1;
+  //   write(fd, (void *)&response, sizeof(response));
+    
+  //   int *client_fd_ptr = malloc(sizeof(int));
+  //   *client_fd_ptr = client_fd;
+
+  //   LOGI("Creating new thread for companion request\n");
+
+  //   pthread_t thread;
+  //   pthread_create(&thread, NULL, ExecuteNew, (void *)client_fd_ptr);
+  //   pthread_detach(thread);
+  // }
+}

zygiskd-new/companion.h

@@ -0,0 +1,6 @@
+#ifndef COMPANION_H
+#define COMPANION_H
+
+void entry(int fd);
+
+#endif /* COMPANION_H */

zygiskd-new/constants.h

@@ -28,15 +28,14 @@
 #endif
 
 #if (defined(__LP64__) || defined(_LP64))
-  #define lp_select(a, b) a
-#else
   #define lp_select(a, b) b
+#else
+  #define lp_select(a, b) a
 #endif
 
-#define PATH_MODULES_DIR ".."
+#define ZYGOTE_INJECTED lp_select(5, 4)
-#define ZYGOTE_INJECTED (lp_select(5, 4))
+#define DAEMON_SET_INFO lp_select(7, 6)
-#define DAEMON_SET_INFO (lp_select(7, 6))
+#define DAEMON_SET_ERROR_INFO lp_select(9, 8)
-#define DAEMON_SET_ERROR_INFO (lp_select(9, 8))
 #define SYSTEM_SERVER_STARTED 10
 
 enum DaemonSocketAction {
@@ -51,14 +50,15 @@ enum DaemonSocketAction {
   SystemServerStarted
 };
 
-enum ProcessFlags {
+enum ProcessFlags: uint32_t {
-  PROCESS_GRANTED_ROOT = 1 << 0,
+  PROCESS_GRANTED_ROOT = (1u << 0),
-  PROCESS_ON_DENYLIST = 1 << 1,
+  PROCESS_ON_DENYLIST = (1u << 1),
-  PROCESS_IS_MANAGER = 1 << 28,
+  PROCESS_IS_MANAGER = (1u << 28),
-  PROCESS_ROOT_IS_APATCH = 1 << 27,
+  PROCESS_ROOT_IS_APATCH = (1u << 27),
-  PROCESS_ROOT_IS_KSU = 1 << 29,
+  PROCESS_ROOT_IS_KSU = (1u << 29),
-  PROCESS_ROOT_IS_MAGISK = 1 << 30,
+  PROCESS_ROOT_IS_MAGISK = (1u << 30),
-  PROCESS_IS_SYSUI = 1 << 31
+  PROCESS_IS_SYS_UI = (1u << 31),
+  PROCESS_IS_SYSUI = (1u << 31)
 };
 
 enum RootImplState {

zygiskd-new/dl.c

@@ -17,7 +17,7 @@ struct AndroidDlextinfo {
   size_t reserved_size;
   int relro_fd;
   int library_fd;
-  __off64_t library_fd_offset;
+  off64_t library_fd_offset;
   struct AndroidNamespace *library_namespace;
 };
 
@@ -45,7 +45,7 @@ void *android_dlopen(char *path, u_int32_t flags) {
       ANDROID_NAMESPACE_TYPE_SHARED,
       NULL,
       NULL,
-      &android_dlopen
+      (void *)&android_dlopen
     );
 
     if (ns != NULL) {

zygiskd-new/dl.h

@@ -3,4 +3,4 @@
 
 void *android_dlopen(char *path, u_int32_t flags);
 
-#endif /* DL_H */
+#endif /* DL_H */

zygiskd-new/main.c

@@ -0,0 +1,93 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include <android/log.h>
+
+#include "root_impl/common.h"
+#include "companion.h"
+#include "zygiskd.h"
+
+#include "utils.h"
+
+int __android_log_print(int prio, const char *tag,  const char *fmt, ...);
+
+int main(int argc, char *argv[]) {
+  errno = 0;
+  /* Initialize android logger */
+  LOGI("Initializing zygiskd\n");
+
+  LOGI("Argc: %d\n", argc);
+  for (int i = 0; i < argc; i++) {
+    LOGI("argv[%d] = %s\n", i, argv[i]);
+  }
+
+  if (argc > 1) {
+    if (strcmp(argv[1], "companion") == 0) {
+      if (argc < 3) {
+        LOGI("Usage: zygiskd companion <fd>\n");
+
+        return 1;
+      }
+
+        LOGI("Previous error{3}: %s\n", strerror(errno));
+
+      int fd = atoi(argv[2]);
+        LOGI("Previous error(4): %s\n", strerror(errno));
+
+      entry(fd);
+
+      return 0;
+    }
+
+    else if (strcmp(argv[1], "version") == 0) {
+      LOGI("ReZygisk Daemon %s\n", ZKSU_VERSION);
+
+      return 0;
+    }
+
+    else if (strcmp(argv[1], "root") == 0) {
+      root_impls_setup();
+      enum RootImpl impl = get_impl();
+
+      switch (impl) {
+        case None: {
+          LOGI("No root implementation found.\n");
+
+          return 1;
+        }
+
+        case Multiple: {
+          LOGI("Multiple root implementations found.\n");
+
+          return 1;
+        }
+
+        case KernelSU: {
+          LOGI("KernelSU root implementation found.\n");
+
+          return 0;
+        }
+      }
+      
+
+      return 0;
+    }
+
+    else {
+      LOGI("Usage: zygiskd [companion|version|root]\n");
+
+      return 0;
+    }
+  }
+
+  LOGI("Previous error{27}: %s\n", strerror(errno));
+  switch_mount_namespace((pid_t)1);
+  LOGI("Previous error{28}: %s\n", strerror(errno));
+  root_impls_setup();
+  LOGI("Previous error{29}: %s\n", strerror(errno));
+  zygiskd_start();
+
+  return 0;
+}

zygiskd-new/root_impl/common.c

@@ -1,10 +1,12 @@
+#include <sys/types.h>
+
 #include "kernelsu.h"
 
 #include "common.h"
 
 static enum RootImpl ROOT_IMPL = None;
 
-void root_impls_setup() {
+void root_impls_setup(void) {
   enum RootImplState ksu_version = ksu_get_kernel_su();
 
   enum RootImpl impl = None;
@@ -14,11 +16,11 @@ void root_impls_setup() {
   ROOT_IMPL = impl;
 }
 
-enum RootImpl get_impl() {
+enum RootImpl get_impl(void) {
   return ROOT_IMPL;
 }
 
-bool uid_granted_root(int uid) {
+bool uid_granted_root(uid_t uid) {
   switch (get_impl()) {
     case KernelSU: {
       return ksu_uid_granted_root(uid);
@@ -29,7 +31,7 @@ bool uid_granted_root(int uid) {
   }
 }
 
-bool uid_should_umount(int uid) {
+bool uid_should_umount(uid_t uid) {
   switch (get_impl()) {
     case KernelSU: {
       return ksu_uid_should_umount(uid);
@@ -40,7 +42,7 @@ bool uid_should_umount(int uid) {
   }
 }
 
-bool uid_is_manager(int uid) {
+bool uid_is_manager(uid_t uid) {
   switch (get_impl()) {
     case KernelSU: {
       return ksu_uid_is_manager(uid);

zygiskd-new/root_impl/common.h

@@ -9,14 +9,14 @@ enum RootImpl {
   KernelSU
 };
 
-void root_impls_setup();
+void root_impls_setup(void);
 
-enum RootImpl get_impl();
+enum RootImpl get_impl(void);
 
-bool uid_granted_root(int uid);
+bool uid_granted_root(uid_t uid);
 
-bool uid_should_umount(int uid);
+bool uid_should_umount(uid_t uid);
 
-bool uid_is_manager(int uid);
+bool uid_is_manager(uid_t uid);
 
 #endif /* COMMON_H */

zygiskd-new/root_impl/kernelsu.c

@@ -1,9 +1,10 @@
 #include <stdlib.h>
-
 #include <sys/stat.h>
 #include <sys/prctl.h>
+#include <errno.h>
 
 #include "../constants.h"
+#include "../utils.h"
 
 #include "kernelsu.h"
 
@@ -13,11 +14,13 @@
 #define CMD_UID_GRANTED_ROOT 12
 #define CMD_UID_SHOULD_UMOUNT 13
 
-enum RootImplState ksu_get_kernel_su() {
+enum RootImplState ksu_get_kernel_su(void) {
   int version = 0;
   prctl(KERNEL_SU_OPTION, CMD_GET_VERSION, &version, 0, 0);
 
-  if (version == 0) return -1;
+  errno = 0;
+
+  if (version == 0) return Abnormal;
 
   if (version >= MIN_KSU_VERSION && version <= MAX_KSU_VERSION) return Supported;
   
@@ -26,29 +29,40 @@ enum RootImplState ksu_get_kernel_su() {
   return Abnormal;
 }
 
-bool ksu_uid_granted_root(int uid) {
+bool ksu_uid_granted_root(uid_t uid) {
   uint32_t result = 0;
   bool granted = false;
   prctl(KERNEL_SU_OPTION, CMD_UID_GRANTED_ROOT, uid, &granted, &result);
 
+  LOGI("ksu_uid_granted_root: %d", granted);
+
   if (result != KERNEL_SU_OPTION) return false;
 
   return granted;
 }
 
-bool ksu_uid_should_umount(int uid) {
+bool ksu_uid_should_umount(uid_t uid) {
   uint32_t result = 0;
   bool umount = false;
   prctl(KERNEL_SU_OPTION, CMD_UID_SHOULD_UMOUNT, uid, &umount, &result);
 
+  LOGI("ksu_uid_should_umount: %d", umount);
+
   if (result != KERNEL_SU_OPTION) return false;
 
   return umount;
 }
 
-bool ksu_uid_is_manager(int uid) {
+bool ksu_uid_is_manager(uid_t uid) {
+
   struct stat s;
-  if (stat("/data/user_de/0/me.weishu.kernelsu", &s) == 0) return s.st_uid == (uid_t)uid;
+  if (stat("/data/user_de/0/me.weishu.kernelsu", &s) == 0) {
+    LOGI("ksu_uid_is_manager: %d", uid);
+
+    return s.st_uid == uid;
+  }
+
+  LOGI("ksu_uid_is_manager: false");
 
   return false;
 }

zygiskd-new/root_impl/kernelsu.h

@@ -0,0 +1,14 @@
+#ifndef KERNELSU_H
+#define KERNELSU_H
+
+#include "../constants.h"
+
+enum RootImplState ksu_get_kernel_su(void);
+
+bool ksu_uid_granted_root(uid_t uid);
+
+bool ksu_uid_should_umount(uid_t uid);
+
+bool ksu_uid_is_manager(uid_t uid);
+
+#endif

zygiskd-new/utils.c

@@ -0,0 +1,300 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <errno.h>
+
+#include <unistd.h>
+#include <linux/limits.h>
+#include <sched.h>
+#include <pthread.h>
+
+#include <android/log.h>
+
+#include "utils.h"
+
+void switch_mount_namespace(pid_t pid) {
+  char current_path[PATH_MAX];
+  if (getcwd(current_path, PATH_MAX) == NULL) {
+    /* TODO: Improve error messages */
+    LOGE("getcwd: %s\n", strerror(errno));
+
+    return;
+  }
+
+  /* INFO: We will NEVER achieve PATH_MAX value, but this is for ensurance. */
+  char path[PATH_MAX];
+  snprintf(path, PATH_MAX, "/proc/%d/ns/mnt", pid);
+
+  FILE *mnt_ns = fopen(path, "r");
+  if (mnt_ns == NULL) {
+    /* TODO: Improve error messages */
+    LOGE("fopen: %s\n", strerror(errno));
+
+    return;
+  }
+
+  if (setns(fileno(mnt_ns), 0) == -1) {
+    /* TODO: Improve error messages */
+    LOGE("setns: %s\n", strerror(errno));
+
+    return;
+  }
+
+  fclose(mnt_ns);
+
+  if (chdir(current_path) == -1) {
+    /* TODO: Improve error messages */
+    LOGE("chdir: %s\n", strerror(errno));
+
+    return;
+  }
+}
+
+int __system_property_get(const char *, char *);
+
+void get_property(const char *name, char *output) {
+  __system_property_get(name, output);
+}
+
+void set_socket_create_context(const char *context) {
+  char path[PATH_MAX];
+  snprintf(path, PATH_MAX, "/proc/thread-self/attr/sockcreate");
+
+  FILE *sockcreate = fopen(path, "w");
+  if (sockcreate == NULL) {
+    LOGE("fopen: %s\n", strerror(errno));
+
+    return;
+  }
+
+  if (fwrite(context, 1, strlen(context), sockcreate) != strlen(context)) {
+    LOGE("fwrite: %s\n", strerror(errno));
+
+    return;
+  }
+
+  fclose(sockcreate);
+}
+
+static void get_current_attr(char *output) {
+  char path[PATH_MAX];
+  snprintf(path, PATH_MAX, "/proc/self/attr/current");
+
+  FILE *current = fopen(path, "r");
+  if (current == NULL) {
+    LOGE("fopen: %s\n", strerror(errno));
+
+    return;
+  }
+
+  if (fgets(output, PATH_MAX, current) == NULL) {
+    LOGE("fgets: %s\n", strerror(errno));
+
+    return;
+  }
+
+  fclose(current);
+}
+
+void unix_datagram_sendto(const char *path, void *buf, size_t len) {
+  char current_attr[PATH_MAX];
+  get_current_attr(current_attr);
+
+  set_socket_create_context(current_attr);
+
+  struct sockaddr_un addr;
+  addr.sun_family = AF_UNIX;
+
+  strncpy(addr.sun_path, path, sizeof(addr.sun_path) - 1);
+
+  int socket_fd = socket(AF_UNIX, SOCK_DGRAM, 0);
+  if (socket_fd == -1) {
+    LOGE("socket: %s\n", strerror(errno));
+
+    return;
+  }
+
+  if (connect(socket_fd, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
+    LOGE("connect: %s\n", strerror(errno));
+
+    return;
+  }
+
+  if (sendto(socket_fd, buf, len, 0, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
+    LOGE("sendto: %s\n", strerror(errno));
+
+    return;
+  }
+
+  set_socket_create_context("u:r:zygote:s0");
+
+  close(socket_fd);
+}
+
+int chcon(const char *path, const char *context) {
+  char command[PATH_MAX];
+  snprintf(command, PATH_MAX, "chcon %s %s", context, path);
+
+  return system(command);
+}
+
+int unix_listener_from_path(char *path) {
+  if (remove(path) == -1 && errno != ENOENT) {
+    LOGE("remove: %s\n", strerror(errno));
+
+    return -1;
+  }
+
+  int socket_fd = socket(AF_UNIX, SOCK_STREAM, 0);
+  if (socket_fd == -1) {
+    LOGE("socket: %s\n", strerror(errno));
+
+    return -1;
+  }
+
+  struct sockaddr_un addr;
+
+  memset(&addr, 0, sizeof(struct sockaddr_un));
+  addr.sun_family = AF_UNIX;
+  strncpy(addr.sun_path, path, sizeof(addr.sun_path) - 1);
+
+  if (bind(socket_fd, (struct sockaddr *)&addr, sizeof(struct sockaddr_un)) == -1) {
+    LOGE("bind: %s\n", strerror(errno));
+
+    return -1;
+  }
+
+  if (listen(socket_fd, 2) == -1) {
+    LOGE("listen: %s\n", strerror(errno));
+
+    return -1;
+  }
+
+  if (chcon(path, "u:object_r:magisk_file:s0") == -1) {
+    LOGE("chcon: %s\n", strerror(errno));
+
+    return -1;
+  }
+
+  return socket_fd;
+}
+
+ssize_t send_fd(int sockfd, int fd) {
+  char control_buf[CMSG_SPACE(sizeof(int))];
+  memset(control_buf, 0, sizeof(control_buf));
+
+  int cnt = 1;
+  struct iovec iov = {
+    .iov_base = &cnt,
+    .iov_len  = sizeof(cnt)
+  };
+
+  struct msghdr msg = {
+    .msg_iov = &iov,
+    .msg_iovlen = 1,
+    .msg_control = control_buf,
+    .msg_controllen = sizeof(control_buf)
+  };
+
+  struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg);
+  cmsg->cmsg_level = SOL_SOCKET;
+  cmsg->cmsg_type = SCM_RIGHTS;
+  cmsg->cmsg_len = CMSG_LEN(sizeof(int));
+
+  memcpy(CMSG_DATA(cmsg), &fd, sizeof(int));
+
+  ssize_t sent_bytes = sendmsg(sockfd, &msg, 0);
+  if (sent_bytes == -1) {
+    LOGE("Failed to send fd: %s\n", strerror(errno));
+
+    return -1;
+  }
+
+  return sent_bytes;
+}
+
+ssize_t recv_fd(int sockfd, int *fd) {
+  char control_buf[CMSG_SPACE(sizeof(int))];
+  memset(control_buf, 0, sizeof(control_buf));
+
+  int cnt = 1;
+  struct iovec iov = {
+    .iov_base = &cnt,
+    .iov_len  = sizeof(cnt)
+  };
+
+  struct msghdr msg = {
+    .msg_iov = &iov,
+    .msg_iovlen = 1,
+    .msg_control = control_buf,
+    .msg_controllen = sizeof(control_buf)
+  };
+
+  ssize_t received_bytes = recvmsg(sockfd, &msg, 0);
+  if (received_bytes == -1) {
+    LOGE("Failed to read fd: %s\n", strerror(errno));
+
+    return -1;
+  }
+
+  struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg);
+  memcpy(fd, CMSG_DATA(cmsg), sizeof(int));
+
+  return received_bytes;
+}
+
+ssize_t write_string(int fd, const char *str) {
+  size_t len = strlen(str);
+
+  ssize_t written_bytes = write(fd, &len, sizeof(len));
+  if (written_bytes != sizeof(len)) {
+    LOGE("Failed to write string length: %s\n", strerror(errno));
+
+    return -1;
+  }
+
+  written_bytes = write(fd, str, len);
+  if ((size_t)written_bytes != len) {
+    LOGE("Failed to write string: Not all bytes were written.\n");
+
+    return -1;
+  }
+
+  return written_bytes;
+}
+
+ssize_t read_string(int fd, char *str, size_t len) {
+  size_t str_len_buf[1];
+
+  LOGI("Reading string length from fd %d\n", fd);
+  LOGI("Previous error: %s\n", strerror(errno));
+
+  ssize_t read_bytes = read(fd, &str_len_buf, sizeof(str_len_buf));
+
+  LOGI("Read %zd bytes\n", read_bytes);
+  if (read_bytes != (ssize_t)sizeof(str_len_buf)) {
+    LOGE("Failed to read string length: %s\n", strerror(errno));
+
+    return -1;
+  }
+  
+  size_t str_len = str_len_buf[0];
+
+  if (str_len > len) {
+    LOGE("Failed to read string: Buffer is too small (%zu > %zu).\n", str_len, len);
+
+    return -1;
+  }
+
+  read_bytes = read(fd, str, str_len);
+  if (read_bytes != (ssize_t)str_len) {
+    LOGE("Failed to read string: Not all bytes were read (%zd != %zu).\n", read_bytes, str_len);
+
+    return -1;
+  }
+
+  return read_bytes;
+}

zygiskd-new/utils.h

@@ -0,0 +1,36 @@
+#ifndef UTILS_H
+#define UTILS_H
+
+#include <sys/types.h>
+
+#include "constants.h"
+
+#define LOGI(...)                                                                          \
+  __android_log_print(ANDROID_LOG_INFO, lp_select("zygiskd32", "zygiskd64"), __VA_ARGS__); \
+  printf(__VA_ARGS__)
+
+#define LOGE(...)                                                                           \
+  __android_log_print(ANDROID_LOG_INFO , lp_select("zygiskd32", "zygiskd64"), __VA_ARGS__); \
+  printf(__VA_ARGS__)
+
+void switch_mount_namespace(pid_t pid);
+
+void get_property(const char *name, char *output);
+
+void set_socket_create_context(const char *context);
+
+void unix_datagram_sendto(const char *path, void *buf, size_t len);
+
+int chcon(const char *path, const char *context);
+
+int unix_listener_from_path(char *path);
+
+ssize_t send_fd(int sockfd, int fd);
+
+ssize_t recv_fd(int sockfd, int *fd);
+
+ssize_t write_string(int fd, const char *str);
+
+ssize_t read_string(int fd, char *str, size_t len);
+
+#endif /* UTILS_H */

zygiskd-new/zygiskd.c

@@ -0,0 +1,722 @@
+#include <stdlib.h>
+#include <string.h>
+#include <dirent.h>
+#include <sys/mman.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <sys/sendfile.h>
+#include <fcntl.h>
+#include <errno.h>
+
+#include <unistd.h>
+#include <linux/limits.h>
+
+#include <pthread.h>
+
+#include "root_impl/common.h"
+#include "constants.h"
+#include "utils.h"
+
+struct Module {
+  char *name;
+  int lib_fd;
+  int companion;
+};
+
+struct Context {
+  struct Module *modules;
+  int len;
+};
+
+enum Architecture {
+  ARM32,
+  ARM64,
+  X86,
+  X86_64,
+};
+
+#define PATH_MODULES_DIR "/data/adb/modules"
+#define TMP_PATH "/data/adb/rezygisk"
+#define CONTROLLER_SOCKET TMP_PATH "/init_monitor"
+#define PATH_CP_NAME TMP_PATH "/" lp_select("cp32.sock", "cp64.sock")
+#define ZYGISKD_FILE "zygiskd" lp_select("32", "64")
+#define ZYGISKD_PATH "/data/adb/modules/zygisksu/bin/zygiskd" lp_select("32", "64")
+
+#define ASSURE_SIZE_WRITE(area_name, subarea_name, sent_size, expected_size)                                    \
+  if (sent_size != (ssize_t)(expected_size)) {                                                                             \
+    LOGE("Failed to sent " subarea_name " in " area_name ": Expected %zu, got %zd\n", expected_size, sent_size); \
+                                                                                                                \
+    return;                                                                                                     \
+  }
+
+#define ASSURE_SIZE_READ(area_name, subarea_name, sent_size, expected_size)                                     \
+  if (sent_size != (ssize_t)(expected_size)) {                                                                             \
+    LOGE("Failed to read " subarea_name " in " area_name ": Expected %zu, got %zd\n", expected_size, sent_size); \
+                                                                                                                \
+    return;                                                                                                     \
+  }
+
+#define ASSURE_SIZE_WRITE_BREAK(area_name, subarea_name, sent_size, expected_size)                               \
+  if (sent_size != (ssize_t)(expected_size)) {                                                                              \
+    LOGE("Failed to sent " subarea_name " in " area_name ": Expected %zu, got %zd\n", expected_size, sent_size); \
+                                                                                                                 \
+    break;                                                                                                       \
+  }
+
+#define ASSURE_SIZE_READ_BREAK(area_name, subarea_name, sent_size, expected_size)                                \
+  if (sent_size != (ssize_t)(expected_size)) {                                                                              \
+    LOGE("Failed to read " subarea_name " in " area_name ": Expected %zu, got %zd\n", expected_size, sent_size); \
+                                                                                                                 \
+    break;                                                                                                       \
+  }
+
+#define ASSURE_SIZE_WRITE_WR(area_name, subarea_name, sent_size, expected_size)                                 \
+  if (sent_size != (ssize_t)(expected_size)) {                                                                             \
+    LOGE("Failed to sent " subarea_name " in " area_name ": Expected %zu, got %zd\n", expected_size, sent_size); \
+                                                                                                                \
+    return -1;                                                                                                  \
+  }
+
+#define ASSURE_SIZE_READ_WR(area_name, subarea_name, sent_size, expected_size)                                  \
+  if (sent_size != (ssize_t)(expected_size)) {                                                                             \
+    LOGE("Failed to read " subarea_name " in " area_name ": Expected %zu, got %zd\n", expected_size, sent_size); \
+                                                                                                                \
+    return -1;                                                                                                  \
+  }
+
+static enum Architecture get_arch(void) {
+  char system_arch[32];
+  get_property("ro.product.cpu.abi", system_arch);
+
+  if (strstr(system_arch, "arm") != NULL) return lp_select(ARM32, ARM64);
+  if (strstr(system_arch, "x86") != NULL) return lp_select(X86, X86_64);
+
+  LOGE("Unsupported system architecture: %s\n", system_arch);
+  exit(1);
+}
+
+int create_library_fd(const char *so_path) {
+  int memfd = memfd_create("jit-cache-zygisk", MFD_ALLOW_SEALING);
+  if (memfd == -1) {
+    perror("memfd_create");
+
+    return -1;
+  }
+
+  int so_fd = open(so_path, O_RDONLY);
+  if (so_fd == -1) {
+    perror("open");
+    close(memfd);
+
+    return -1;
+  }
+
+  struct stat st;
+  if (fstat(so_fd, &st) == -1) {
+    perror("fstat");
+    close(so_fd);
+    close(memfd);
+
+    return -1;
+  }
+
+  if (sendfile(memfd, so_fd, NULL, st.st_size) == -1) {
+    perror("sendfile");
+    close(so_fd);
+    close(memfd);
+
+    return -1;
+  }
+
+  close(so_fd);
+
+  if (fcntl(memfd, F_ADD_SEALS, F_SEAL_SHRINK | F_SEAL_GROW | F_SEAL_WRITE | F_SEAL_SEAL) == -1) {
+    perror("fcntl");
+    close(memfd);
+
+    return -1;
+  }
+
+  return memfd;
+}
+
+
+/* WARNING: Dynamic memory based */
+static void load_modules(enum Architecture arch, struct Context *context) {
+  context->len = 0;
+  context->modules = malloc(1);
+
+  // LOGI("Previous error{25}: %s\n", strerror(errno));
+
+  DIR *dir = opendir(PATH_MODULES_DIR);
+  if (dir == NULL) {
+    LOGE("Failed opening modules directory: %s.", PATH_MODULES_DIR);
+
+    return;
+  }
+
+  // LOGI("Previous error{27}: %s\n", strerror(errno));
+
+  char arch_str[32];
+  switch (arch) {
+    case ARM32: {
+      strcpy(arch_str, "armeabi-v7a");
+
+      break;
+    }
+    case ARM64: {
+      strcpy(arch_str, "arm64-v8a");
+
+      break;
+    }
+    case X86: {
+      strcpy(arch_str, "x86");
+  
+      break;
+    }
+    case X86_64: {
+      strcpy(arch_str, "x86_64");
+
+      break;
+    }
+  }
+
+  LOGI("Loading modules for architecture: %s\n", arch_str);
+  // LOGI("Previous error{28}: %s\n", strerror(errno));
+
+  struct dirent *entry;
+  while ((entry = readdir(dir)) != NULL) {
+    // LOGI("Previous error{29}: %s\n", strerror(errno));
+    if (entry->d_type != DT_DIR) continue; /* INFO: Only directories */
+    if (strcmp(entry->d_name, ".") == 0 || strcmp(entry->d_name, "..") == 0 || strcmp(entry->d_name, "zygisksu") == 0) continue;
+
+    char *name = entry->d_name;
+    char so_path[PATH_MAX];
+    snprintf(so_path, PATH_MAX, "/data/adb/modules/%s/zygisk/%s.so", name, arch_str);
+
+    struct stat st;
+    if (stat(so_path, &st) == -1) {
+      errno = 0;
+
+      continue;
+    }
+
+    char disabled[PATH_MAX];
+    snprintf(disabled, PATH_MAX, "/data/adb/modules/%s/disable", name);
+
+    if (stat(disabled, &st) != -1) {
+      errno = 0;
+
+      continue;
+    }
+
+    LOGI("Loading module `%s`...\n", name);
+    int lib_fd = create_library_fd(so_path);
+    if (lib_fd == -1) {
+      LOGE("Failed loading module `%s`\n", name);
+
+      continue;
+    }
+
+    LOGI("Loaded module lib fd: %d\n", lib_fd);
+
+    context->modules = realloc(context->modules, ((context->len + 1) * sizeof(struct Module)));
+    context->modules[context->len].name = strdup(name);
+    context->modules[context->len].lib_fd = lib_fd;
+    context->modules[context->len].companion = -1;
+    context->len++;
+  }
+}
+
+static void free_modules(struct Context *context) {
+  for (int i = 0; i < context->len; i++) {
+    free(context->modules[i].name);
+    if (context->modules[i].companion != -1) close(context->modules[i].companion);
+  }
+}
+
+static int create_daemon_socket(void) {
+  set_socket_create_context("u:r:zygote:s0");
+  
+  return unix_listener_from_path(PATH_CP_NAME);
+}
+
+static int spawn_companion(char *name, int lib_fd) {
+  // LOGI("Previous error{15}: %s\n", strerror(errno));
+
+  int sockets[2];
+  if (socketpair(AF_UNIX, SOCK_STREAM, 0, sockets) == -1) {
+    LOGE("Failed creating socket pair.\n");
+
+    return -1;
+  }
+
+  int daemon_fd = sockets[0];
+  int companion_fd = sockets[1];
+
+  LOGI("Companion fd: %d\n", companion_fd);
+  LOGI("Daemon fd: %d\n", daemon_fd);
+
+  // LOGI("Previous error{13}: %s\n", strerror(errno));
+
+  pid_t pid = fork();
+  LOGI("Forked: %d\n", pid);
+  if (pid < 0) {
+    LOGE("Failed forking companion: %s\n", strerror(errno));
+
+    close(companion_fd);
+    close(daemon_fd);
+
+    exit(1);
+  } else if (pid > 0) {
+    // LOGI("Previous error{11}: %s\n", strerror(errno));
+
+    close(companion_fd);
+
+    LOGI("Waiting for companion to start (%d)\n", pid);
+    //  LOGI("Previous error{8}: %s\n", strerror(errno));
+
+    int status;
+    waitpid(pid, &status, 0);
+
+    LOGI("Companion exited with status %d\n", status);
+    //  LOGI("Previous error{9}: %s\n", strerror(errno));
+
+    if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
+      if (write_string(daemon_fd, name) == -1) return -1;
+
+      if (send_fd(daemon_fd, lib_fd) == -1) return -1;
+
+      LOGI("Sent module name and lib fd\n");
+      
+      uint8_t response_buf[1];
+      ssize_t ret = read(daemon_fd, &response_buf, sizeof(response_buf));
+      ASSURE_SIZE_READ_WR("companion", "response", ret, sizeof(response_buf));
+
+      uint8_t response = response_buf[0];
+
+      LOGI("Companion response: %hhu\n", response);
+
+      if (response == 0) return -2;
+      else if (response == 1) return daemon_fd;
+      else return -2;
+    } else {
+      LOGE("Exited with status %d\n", status);
+
+      close(daemon_fd);
+
+      return -1;
+    }
+  /* INFO: if pid == 0: */
+  } else {
+    LOGI("Companion started (%d)\n", pid);
+    /* INFO: There is no case where this will fail with a valid fd. */
+    fcntl(companion_fd, F_SETFD, 0);
+  }
+
+  char companion_fd_str[32];
+  snprintf(companion_fd_str, 32, "%d", companion_fd);
+
+  LOGI("Executing companion...\n");
+  //  LOGI("Previous error{10}: %s\n", strerror(errno));
+
+  char *argv[] = { ZYGISKD_FILE, "companion", companion_fd_str, NULL };
+  if (execv(ZYGISKD_PATH, argv) == -1) {
+    LOGE("Failed executing companion: %s\n", strerror(errno));
+
+    close(companion_fd);
+
+    exit(1);
+  }
+
+  exit(0);
+}
+
+/* TODO: Is packed attribute really necessary? */
+struct __attribute__((__packed__)) MsgHead {
+  unsigned int cmd;
+  int length;
+  char data[0];
+};
+
+void zygiskd_start(void) {
+  LOGI("Welcome to ReZygisk %s!", ZKSU_VERSION);
+
+  // LOGI("Previous error{26}: %s\n", strerror(errno));
+
+  enum Architecture arch = get_arch();
+
+  // LOGI("Previous error{25}: %s\n", strerror(errno));
+
+  struct Context context;
+  load_modules(arch, &context);
+
+  struct MsgHead *msg = NULL;
+  size_t msg_sz = 0;
+
+  // LOGI("Previous error{24}: %s\n", strerror(errno));
+
+  switch (get_impl()) {
+    case None: {
+      /* INFO: Stop, compiler. */
+
+      break;
+    }
+    case Multiple: {
+      /* INFO: Stop, compiler. */
+
+      break;
+    }
+
+    case KernelSU: {
+      if (context.len == 0) {
+        msg_sz = sizeof(struct MsgHead) + strlen("Root: KernelSU, Modules: None") + 1;
+        msg = malloc(msg_sz);
+
+        msg->cmd = DAEMON_SET_INFO;
+        msg->length = strlen("Root: KernelSU, Modules: None") + 1;
+        memcpy(msg->data, "Root: KernelSU, Modules: None", strlen("Root: KernelSU, Modules: None"));
+      } else {
+        char *module_list = malloc(1);
+        size_t module_list_len = 0;
+
+        for (int i = 0; i < context.len; i++) {
+          if (i != context.len - 1) {
+            module_list = realloc(module_list, module_list_len + strlen(context.modules[i].name) + strlen(", ") + 1);
+            memcpy(module_list + module_list_len, context.modules[i].name, strlen(context.modules[i].name));
+
+            module_list_len += strlen(context.modules[i].name);
+
+            memcpy(module_list + module_list_len, ", ", strlen(", "));
+
+            module_list_len += strlen(", ");
+          } else {
+            module_list = realloc(module_list, module_list_len + strlen(context.modules[i].name) + 1);
+            memcpy(module_list + module_list_len, context.modules[i].name, strlen(context.modules[i].name));
+
+            module_list_len += strlen(context.modules[i].name);
+          }
+        }
+
+        msg_sz = sizeof(struct MsgHead) + strlen("Root: KernelSU, Modules: ") + module_list_len + 1;
+        msg = malloc(msg_sz);
+
+        msg->cmd = DAEMON_SET_INFO;
+        msg->length = strlen("Root: KernelSU, Modules: ") + module_list_len + 1;
+        memcpy(msg->data, "Root: KernelSU, Modules: ", strlen("Root: KernelSU, Modules: "));
+        memcpy(msg->data + strlen("Root: KernelSU, Modules: "), module_list, module_list_len);
+
+        free(module_list);
+      }
+
+      break;
+    }
+    default: {
+      msg_sz = sizeof(struct MsgHead) + strlen("Invalid root implementation") + 1;
+      msg = malloc(msg_sz);
+
+      msg->cmd = DAEMON_SET_ERROR_INFO;
+      msg->length = strlen("Invalid root implementation") + 1;
+      memcpy(msg->data, "Invalid root implementation", strlen("Invalid root implementation"));
+
+      break;
+    }
+  }
+
+  // LOGI("Previous error{22}: %s\n", strerror(errno));
+
+  unix_datagram_sendto(CONTROLLER_SOCKET, (void *)msg, msg_sz);
+
+  free(msg);
+
+  // LOGI("Previous error{21}: %s\n", strerror(errno));
+
+  int socket_fd = create_daemon_socket();
+  if (socket_fd == -1) {
+    LOGE("Failed creating daemon socket\n");
+
+    return;
+  }
+
+  while (1) {
+    // LOGI("Previous error{20}: %s\n", strerror(errno));
+    int client_fd = accept(socket_fd, NULL, NULL);
+    if (client_fd == -1) {
+      LOGE("accept: %s\n", strerror(errno));
+
+      return;
+    }
+
+    LOGI("Accepted client: %d\n", client_fd);
+
+    // LOGI("Previous error{19}: %s\n", strerror(errno));
+
+    unsigned char buf[1];
+    ssize_t len = read(client_fd, buf, sizeof(buf));
+    if (len == -1) {
+      LOGE("read: %s\n", strerror(errno));
+
+      return;
+    } else if (len == 0) {
+      LOGI("Client disconnected\n");
+
+      return;
+    }
+
+    LOGI("Action: %hhu\n", (uint8_t)buf[0]);
+    enum DaemonSocketAction action = (enum DaemonSocketAction)buf[0];
+
+    switch (action) {
+      case PingHeartbeat: {
+        enum DaemonSocketAction msgr = ZYGOTE_INJECTED;
+        unix_datagram_sendto(CONTROLLER_SOCKET, &msgr, sizeof(enum DaemonSocketAction));
+
+        break;
+      }
+      case ZygoteRestart: {
+        LOGI("Zygote restart\n");
+
+        for (int i = 0; i < context.len; i++) {
+          if (context.modules[i].companion != -1) {
+            close(context.modules[i].companion);
+            context.modules[i].companion = -1;
+          }
+        }
+
+        break;
+      }
+      case SystemServerStarted: {
+        enum DaemonSocketAction msgr = SYSTEM_SERVER_STARTED;
+        unix_datagram_sendto(CONTROLLER_SOCKET, &msgr, sizeof(enum DaemonSocketAction));
+
+        break;
+      }
+      case RequestLogcatFd: {
+        char level_buf[1];
+        ssize_t ret = read(client_fd, &level_buf, sizeof(level_buf));
+        ASSURE_SIZE_READ_BREAK("RequestLogcatFd", "level", ret, sizeof(level_buf));
+
+        char level = level_buf[0];
+
+        char tag[128 + 1];
+        ret = read_string(client_fd, tag, sizeof(tag) - 1);
+        if (ret == -1) break;
+
+        tag[ret] = '\0';
+
+        char message[1024];
+        ret = read_string(client_fd, message, sizeof(message));
+        if (ret == -1) break;
+
+        __android_log_print(level, tag, "%.*s", (int)ret, message);
+
+        break;
+      }
+      case GetProcessFlags: {
+        LOGI("Getting process flags\n");
+
+        uid_t uid_buf[1];
+        ssize_t ret = read(client_fd, &uid_buf, sizeof(uid_buf));
+        ASSURE_SIZE_READ_BREAK("GetProcessFlags", "uid", ret, sizeof(uid_buf));
+
+        uid_t uid = uid_buf[0];
+
+        LOGI("Checking flags for uid: %d\n", uid);
+
+        uint32_t flags = 0;
+        if (uid_is_manager(uid)) {
+          flags |= PROCESS_IS_MANAGER;
+        } else {
+          if (uid_granted_root(uid)) {
+            flags |= PROCESS_GRANTED_ROOT;
+          }
+          if (uid_should_umount(uid)) {
+            flags |= PROCESS_ON_DENYLIST;
+          }
+        }
+
+        LOGI("Flags for uid %d: %d\n", uid, flags);
+
+        switch (get_impl()) {
+          case None: {
+            break;
+          }
+          case Multiple: {
+            break;
+          }
+          case KernelSU: {
+            flags |= PROCESS_ROOT_IS_KSU;
+          }
+        }
+
+        // LOGI("Flags for uid %d: %d\n", uid, flags);
+
+        LOGI("Sending flags\n");
+
+        ret = write(client_fd, &flags, sizeof(flags));
+        // ASSURE_SIZE_WRITE_BREAK("GetProcessFlags", "flags", ret, sizeof(flags));
+
+        LOGI("Sent flags\n");
+
+        break;
+      }
+      case GetInfo: {
+        uint32_t flags = 0;
+
+        LOGI("Getting info\n");
+
+        switch (get_impl()) {
+          case None: {
+            break;
+          }
+          case Multiple: {
+            break;
+          }
+          case KernelSU: {
+            flags |= PROCESS_ROOT_IS_KSU;
+          }
+        }
+
+        LOGI("Flags: %d\n", flags);
+
+        ssize_t ret = write(client_fd, &flags, sizeof(flags));
+        ASSURE_SIZE_WRITE_BREAK("GetInfo", "flags", ret, sizeof(flags));
+
+        pid_t pid = getpid();
+
+        LOGI("Getting pid: %d\n", pid);
+    
+        ret = write(client_fd, &pid, sizeof(pid));
+        ASSURE_SIZE_WRITE_BREAK("GetInfo", "pid", ret, sizeof(pid));
+
+        LOGI("Sent pid\n");
+
+        break;
+      }
+      case ReadModules: {
+        LOGI("Reading modules to stream\n");
+
+        size_t clen = context.len;
+        ssize_t ret = write(client_fd, &clen, sizeof(clen));
+        ASSURE_SIZE_WRITE_BREAK("ReadModules", "len", ret, sizeof(clen));
+
+        for (int i = 0; i < (int)clen; i++) {
+          LOGI("Hey, we're talking about: %d\n", i);
+          LOGI("Writing module `%s` to stream\n", context.modules[i].name);
+          LOGI("Lib fd: %d\n", context.modules[i].lib_fd);
+
+          size_t name_len = strlen(context.modules[i].name);
+
+          LOGI("Name length: %zu\n", name_len);
+          ret = write(client_fd, &name_len, sizeof(name_len));
+          ASSURE_SIZE_WRITE_BREAK("ReadModules", "name length", ret, sizeof(name_len));
+
+          LOGI("Writing name: %s\n", context.modules[i].name);
+          ret = write(client_fd, context.modules[i].name, name_len);
+          ASSURE_SIZE_WRITE_BREAK("ReadModules", "name", ret, name_len);
+
+          LOGI("Writing lib fd: %d\n", context.modules[i].lib_fd);
+          if (send_fd(client_fd, context.modules[i].lib_fd) == -1) break;
+        }
+
+        LOGI("Finished reading modules to stream\n");
+
+        break;
+      }
+      case RequestCompanionSocket: {
+        LOGI("Requesting companion socket\n");
+
+        // LOGI("Previous error{17}: %s\n", strerror(errno));
+      
+        size_t index_buf[1];
+        ssize_t ret = read(client_fd, &index_buf, sizeof(index_buf));
+        ASSURE_SIZE_READ_BREAK("RequestCompanionSocket", "index", ret, sizeof(index_buf));
+
+        // LOGI("Previous error{16}: %s\n", strerror(errno));
+
+        size_t index = index_buf[0];
+
+        struct Module *module = &context.modules[index];
+        int companion_fd = module->companion;
+
+        if (companion_fd != -1) {
+          LOGI("Companion for module `%s` already exists\n", module->name);
+
+          if (fcntl(companion_fd, F_GETFD) == -1) {
+            LOGE("Poll companion for module `%s` crashed\n", module->name);
+            close(companion_fd);
+
+            module->companion = -1;
+          }
+        }
+
+        if (companion_fd == -1) {
+          LOGI("Spawning companion for `%s`\n", module->name);
+
+          companion_fd = spawn_companion(module->name, module->lib_fd);
+
+          if (companion_fd != -1) {
+            LOGI("Spawned companion for `%s`\n", module->name);
+
+            module->companion = companion_fd;
+
+            if (send_fd(client_fd, companion_fd) == -1) break;
+          } else if (companion_fd == -2) {
+            LOGI("Could not spawn companion for `%s` as it has no entry\n", module->name);
+
+            /* TODO: Avoid duplicated code -- Merge this and the one below. */
+            uint8_t response = 0;
+            ret = write(client_fd, &response, sizeof(response));
+            ASSURE_SIZE_WRITE_BREAK("RequestCompanionSocket", "response", ret, sizeof(response));
+          } else {
+            LOGE("Failed to spawn companion for `%s`\n", module->name);
+
+            uint8_t response = 0;
+            ret = write(client_fd, &response, sizeof(response));
+            ASSURE_SIZE_WRITE_BREAK("RequestCompanionSocket", "response", ret, sizeof(response));
+          }
+
+          LOGI("Companion fd: %d\n", companion_fd);
+        }
+
+        break;
+      }
+      case GetModuleDir: {
+        LOGI("Getting module directory\n");
+
+        size_t index_buf[1];
+        ssize_t ret = read(client_fd, &index_buf, sizeof(index_buf));
+        ASSURE_SIZE_READ_BREAK("GetModuleDir", "index", ret, sizeof(index_buf));
+
+        size_t index = index_buf[0];
+
+        LOGI("Index: %zu\n", index);
+
+        char dir[PATH_MAX];
+        snprintf(dir, PATH_MAX, "%s/%s", PATH_MODULES_DIR, context.modules[index].name);
+
+        LOGI("Module directory: %s\n", dir);
+        int dir_fd = open(dir, O_RDONLY);
+
+        LOGI("Module directory fd: %d\n", dir_fd);
+
+        if (send_fd(client_fd, dir_fd) == -1) break;
+
+        LOGI("Sent module directory fd\n");
+
+        break;
+      }
+
+
+
+      close(client_fd);
+    }
+
+    continue;
+  }
+
+  close(socket_fd);
+  free_modules(&context);
+}

zygiskd-new/zygiskd.h

@@ -0,0 +1,6 @@
+#ifndef ZYGISKD_H
+#define ZYGISKD_H
+
+void zygiskd_start(void);
+
+#endif /* ZYGISKD_H */

zygiskd/Makefile

@@ -1,19 +0,0 @@
-CC := ~/Android/Sdk/ndk/27.0.11902837/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android34-clang
-
-FILES = root_impl/common.c   \
-        root_impl/kernelsu.c \
-				main.c               \
-				utils.c              \
-
-CFLAGS = -D_GNU_SOURCE -Wall -Wextra -Werror -O3 -Iroot_impl -llog
-
-all: CFLAGS += -DDEBUG=0
-all:
-	$(CC) $(CFLAGS) $(FILES) -o zygiskd
-
-debug: CFLAGS += -DDEBUG=1
-debug:
-	$(CC) $(CFLAGS) $(FILES) -o zygiskd
-
-clean:
-	rm -f zygiskd

zygiskd/companion.c

@@ -1,96 +0,0 @@
-#include <stdio.h>
-#include <stdlib.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <sys/stat.h>
-#include <dlfcn.h>
-
-#include <unistd.h>
-#include <linux/limits.h>
-#include <pthread.h>
-
-#include "dl.h"
-#include "utils.h"
-
-typedef void (*ZygiskCompanionEntryFn)(u_int32_t);
-
-ZygiskCompanionEntryFn load_module(u_int32_t fd) {
-  char path[PATH_MAX];
-  snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);
-
-  void *handle = android_dlopen(path, RTLD_NOW);
-  void *entry = dlsym(handle, "zygisk_companion_entry");
-  if (entry == NULL) return NULL;
-
-  return (ZygiskCompanionEntryFn)entry;
-}
-
-void *ExecuteNew(void *arg) {
-  u_int32_t fd = (u_int32_t)arg;
-
-  struct stat st0;
-  if (fstat(fd) == -1) {
-    printf("Failed to stat client fd\n");
-
-    exit(0);
-  }
-  entry(fd);
-
-  // Only close client if it is the same file so we don't
-  // accidentally close a re-used file descriptor.
-  // This check is required because the module companion
-  // handler could've closed the file descriptor already.
-  struct stat st1;
-  if (fstat(fd) == -1) {
-    printf("Failed to stat client fd\n");
-
-    exit(0);
-  }
-
-  if (st0.st_dev != st1.st_dev || st0.st_ino != st1.st_ino) {
-    close(fd);
-  }
-
-  return NULL;
-}
-
-void entry(u_int32_t fd) {
-  printf("companion entry fd=%d\n", fd);
-
-  char name[256];
-  read(fd, name, 256);
-
-  int library_fd;
-  read(fd, &library_fd, sizeof(library_fd));
-
-  ZygiskCompanionEntryFn entry = load_module(library_fd);
-
-  close(library_fd);
-
-  if (entry == NULL) {
-    printf("No companion entry for `%s`\n", name);
-
-    write(fd, (void *)0, 1);
-
-    exit(0);
-  }
-
-  printf("Companion process created for `%s`\n", name);
-
-  write(fd, (void *)1, 1);
-
-  while (1) {
-    int client_fd;
-    read(fd, &client_fd, sizeof(client_fd));
-
-    printf("New companion request from module `%s` fd=`%d`\n", name, client_fd);
-
-    write(fd, (void *)1, 1);
-
-    pthread_t thread;
-    pthread_create(&thread, NULL, ExecuteNew, (void *)client_fd);
-    pthread_detach(thread);
-
-
-  }
-}

zygiskd/main.c

@@ -1,83 +0,0 @@
-#include <stdio.h>
-#include <string.h>
-
-#include <android/log.h>
-
-#include "root_impl/common.h"
-
-#include "utils.h"
-
-// extern "C" {
-//     fn __android_log_print(prio: i32, tag: *const c_char, fmt: *const c_char, ...) -> i32;
-//     fn __system_property_get(name: *const c_char, value: *mut c_char) -> u32;
-//     fn __system_property_set(name: *const c_char, value: *const c_char) -> u32;
-//     fn __system_property_find(name: *const c_char) -> *const c_void;
-//     fn __system_property_wait(
-//         info: *const c_void,
-//         old_serial: u32,
-//         new_serial: *mut u32,
-//         timeout: *const libc::timespec,
-//     ) -> bool;
-//     fn __system_property_serial(info: *const c_void) -> u32;
-// }
-
-int __android_log_print(int prio, const char *tag,  const char *fmt, ...);
-
-int main(int argc, char *argv[]) {
-  /* Initialize android logger */
-  __android_log_print(ANDROID_LOG_INFO, "zygiskd", "Hello, world! :3");
-
-  if (argc > 1) {
-    if (strcmp(argv[0], "companion") == 0) {
-      /* WIP */
-
-      return 0;
-    }
-
-    else if (strcmp(argv[1], "version") == 0) {
-      printf("ReZygisk Daemon %s\n", ZKSU_VERSION);
-
-      return 0;
-    }
-
-    else if (strcmp(argv[1], "root") == 0) {
-      root_impls_setup();
-      enum RootImpl impl = get_impl();
-
-      switch (impl) {
-        case None: {
-          printf("No root implementation found.\n");
-
-          return 1;
-        }
-
-        case Multiple: {
-          printf("Multiple root implementations found.\n");
-
-          return 1;
-        }
-
-        case KernelSU: {
-          printf("KernelSU root implementation found.\n");
-
-          return 0;
-        }
-      }
-      
-
-      return 0;
-    }
-
-    else {
-      printf("Usage: zygiskd [companion|version|root]\n");
-
-      return 0;
-    }
-  }
-
-  switch_mount_namespace((pid_t)1);
-  root_impls_setup();
-  __android_log_print(ANDROID_LOG_INFO, "zygiskd", "Root implementation: %d", get_impl());
-
-  return 0;
-}

zygiskd/root_impl/kernelsu.h

@@ -1,14 +0,0 @@
-#ifndef KERNELSU_H
-#define KERNELSU_H
-
-#include "../constants.h"
-
-enum RootImplState ksu_get_kernel_su();
-
-bool ksu_uid_granted_root(int uid);
-
-bool ksu_uid_should_umount(int uid);
-
-bool ksu_uid_is_manager(int uid);
-
-#endif

zygiskd/utils.c

@@ -1,172 +0,0 @@
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <sys/un.h>
-
-#include <unistd.h>
-#include <linux/limits.h>
-#include <sched.h>
-
-#include <pthread.h>
-
-void switch_mount_namespace(pid_t pid) {
-  char current_path[PATH_MAX];
-  if (getcwd(current_path, PATH_MAX) == NULL) {
-    /* TODO: Improve error messages */
-    perror("getcwd");
-
-    return;
-  }
-
-  /* INFO: We will NEVER achieve PATH_MAX value, but this is for ensurance. */
-  char path[PATH_MAX];
-  snprintf(path, PATH_MAX, "/proc/%d/ns/mnt", pid);
-
-  FILE *mnt_ns = fopen(path, "r");
-  if (mnt_ns == NULL) {
-    /* TODO: Improve error messages */
-    perror("fopen");
-
-    return;
-  }
-
-  if (setns(fileno(mnt_ns), 0) == -1) {
-    /* TODO: Improve error messages */
-    perror("setns");
-
-    return;
-  }
-
-  fclose(mnt_ns);
-
-  if (chdir(current_path) == -1) {
-    /* TODO: Improve error messages */
-    perror("chdir");
-
-    return;
-  }
-}
-
-int __system_property_get(const char *, char *);
-
-void get_property(const char *name, char *output) {
-  __system_property_get(name, output);
-}
-
-void set_socket_create_context(const char *context) {
-  char path[PATH_MAX];
-  snprintf(path, PATH_MAX, "/proc/thread-self/attr/sockcreate");
-
-  FILE *sockcreate = fopen(path, "w");
-  if (sockcreate == NULL) {
-    perror("fopen");
-
-    return;
-  }
-
-  if (fwrite(context, 1, strlen(context), sockcreate) != strlen(context)) {
-    perror("fwrite");
-
-    return;
-  }
-
-  fclose(sockcreate);
-}
-
-void get_current_attr(char *output) {
-  char path[PATH_MAX];
-  snprintf(path, PATH_MAX, "/proc/self/attr/current");
-
-  FILE *current = fopen(path, "r");
-  if (current == NULL) {
-    perror("fopen");
-
-    return;
-  }
-
-  if (fgets(output, PATH_MAX, current) == NULL) {
-    perror("fgets");
-
-    return;
-  }
-
-  fclose(current);
-}
-
-void unix_datagram_sendto(const char *path, const char *buf) {
-  char current_attr[PATH_MAX];
-  get_current_attr(current_attr);
-
-  set_socket_create_context(current_attr);
-
-  struct sockaddr_un addr;
-  addr.sun_family = AF_UNIX;
-  strncpy(addr.sun_path, path, sizeof(addr.sun_path) - 1);
-
-  int socket_fd = socket(AF_UNIX, SOCK_DGRAM, 0);
-  if (socket_fd == -1) {
-    perror("socket");
-
-    return;
-  }
-
-  if (connect(socket_fd, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
-    perror("connect");
-
-    return;
-  }
-
-  if (sendto(socket_fd, buf, strlen(buf), 0, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
-    perror("sendto");
-
-    return;
-  }
-
-  set_socket_create_context("u:r:zygote:s0");
-
-  close(socket_fd);
-}
-
-int chcon(const char *path, const char *context) {
-  char command[PATH_MAX];
-  snprintf(command, PATH_MAX, "chcon %s %s", context, path);
-
-  return system(command);
-}
-
-int unix_listener_from_path(char *path) {
-  remove(path);
-
-  struct sockaddr_un addr;
-  addr.sun_family = AF_UNIX;
-  strncpy(addr.sun_path, path, sizeof(addr.sun_path) - 1);
-
-  int socket_fd = socket(AF_UNIX, SOCK_STREAM, 0);
-  if (socket_fd == -1) {
-    perror("socket");
-
-    return -1;
-  }
-
-  if (bind(socket_fd, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
-    perror("bind");
-
-    return -1;
-  }
-
-  if (listen(socket_fd, 2) == -1) {
-    perror("listen");
-
-    return -1;
-  }
-
-  if (chcon(path, "u:object_r:magisk_file:s0") == -1) {
-    perror("chcon");
-
-    return -1;
-  }
-
-  return socket_fd;
-}

zygiskd/utils.h

@@ -1,16 +0,0 @@
-#ifndef UTILS_H
-#define UTILS_H
-
-#include <sys/types.h>
-
-void switch_mount_namespace(pid_t pid);
-
-void get_property(const char *name, char *output);
-
-void set_socket_create_context(const char *context);
-
-void unix_datagram_sendto(const char *path, const char *buf);
-
-int unix_listener_from_path(char *path);
-
-#endif /* UTILS_H */

zygiskd/zygiskd.c

@@ -1,353 +0,0 @@
-#include <unistd.h>
-#include <linux/limits.h>
-#include <sys/mman.h>
-#include <sys/socket.h>
-
-#include "root_impl/common.h"
-#include "constants.h"
-#include "utils.h"
-
-struct Module {
-  char *name;
-  int lib_fd;
-}
-
-struct Context {
-  struct Module *modules;
-}
-
-enum Architecture {
-  ARM32,
-  ARM64,
-  X86,
-  X86_64,
-}
-
-static char TMP_PATH[] = "/data/adb/rezygisk";
-static char CONTROLLER_SOCKET[PATH_MAX];
-static char PATH_CP_NAME[PATH_MAX];
-
-enum Architecture get_arch() {
-  char system_arch[PROP_VALUE_MAX];
-  get_property("ro.product.cpu.abi", system_arch);
-
-  if (strstr(system_arch, "arm") != NULL) return lp_select(ARM32, ARM64);
-  if (strstr(system_arch, "x86") != NULL) return lp_select(ARM64, X86_64);
-
-  printf("Unsupported system architecture: %s\n", system_arch);
-  exit(1);
-}
-
-int create_library_fd(char *so_path) {
-  int memfd = memfd_create("jit-cache-zygisk", MFD_ALLOW_SEALING);
-  if (memfd == -1) {
-    printf("Failed creating memfd: %s\n", strerror(errno));
-    return -1;
-  }
-
-  int file = open(so_path, O_RDONLY);
-  if (file == -1) {
-    printf("Failed opening file: %s\n", strerror(errno));
-    return -1;
-  }
-
-  struct stat st;
-  fstat(file, &st);
-  ftruncate(memfd, st.st_size);
-
-  void *addr = mmap(NULL, st.st_size, PROT_READ | PROT_WRITE, MAP_SHARED, memfd, 0);
-  if (addr == MAP_FAILED) {
-    printf("Failed mapping memory: %s\n", strerror(errno));
-    return -1;
-  }
-
-  read(file, addr, st.st_size);
-  munmap(addr, st.st_size);
-  close(file);
-
-  unsigned int seals = F_SEAL_SHRINK | F_SEAL_GROW | F_SEAL_WRITE | F_SEAL_SEAL;
-  if (fcntl(memfd, F_ADD_SEALS, seals) == -1) {
-    printf("Failed adding seals: %s\n", strerror(errno));
-    return -1;
-  }
-
-  return memfd;
-}
-
-/* WARNING: Dynamic memory based */
-struct Module **load_modules(enum Architecture arch) {
-  struct Module **modules = malloc(sizeof(struct Module *));
-  DIR *dir = opendir(PATH_MODULES_DIR);
-
-  struct dirent *entry;
-  while ((entry = readdir(dir)) != NULL) {
-    char *name = entry->d_name;
-    char so_path[PATH_MAX];
-    snprintf(so_path, PATH_MAX, "%s/zygisk/%s.so", PATH_MODULES_DIR, name);
-
-    struct stat st;
-    if (stat(so_path, &st) == -1) continue;
-
-    char disabled[PATH_MAX];
-    snprintf(disabled, PATH_MAX, "%s/disable", PATH_MODULES_DIR);
-    if (stat(disabled, &st) != -1) continue;
-
-    printf("Loading module `%s`...\n", name);
-    int lib_fd = create_library_fd(so_path);
-    if (lib_fd == -1) continue;
-
-    struct Module *module = malloc(sizeof(struct Module));
-    module->name = name;
-    module->lib_fd = lib_fd;
-    modules = realloc(modules, sizeof(modules) + sizeof(module));
-    modules[sizeof(modules)] = module;
-  }
-
-  return modules;
-}
-
-void free_modules(struct Module **modules) {
-  for (int i = 0; i < sizeof(modules); i++) {
-    free(modules[i]);
-  }
-
-  free(modules);
-}
-
-int create_daemon_socket() {
-  set_socket_create_context("u:r:zygote:s0");
-  int socket_fd = unix_listener_from_path(PATH_CP_NAME);
-
-  return socket_fd;
-}
-
-void zygiskd_start() {
-  printf("Welcome to ReZygisk %s!\n", ZKSU_VERSION);
-
-  snprintf(CONTROLLER_SOCKET, PATH_MAX, "%s/init_monitor", TMP_PATH);
-  snprintf(PATH_CP_NAME, PATH_MAX, "%s/%s", TMP_PATH, lp_select("/cp32.sock", "/cp64.sock"));
-
-  Architecture arch = get_arch();
-  printf("Daemon architecture: %s\n", arch);
-
-  struct Module **modules = load_modules(arch);
-
-  char *msg = malloc(1);
-  size_t msg_len = 1;
-
-  switch (get_impl()) {
-    case KernelSU: {
-      msg[0] = DAEMON_SET_INFO;
-
-      msg = realloc(msg, strlen("Root: KernelSU, Modules: ") + 1);
-      memcpy(msg + 1, "Root: KernelSU, Modules: ", strlen("Root: KernelSU, Modules: "));
-      msg_len += strlen("Root: KernelSU, Modules: ");
-
-      for (int i = 0; i < sizeof(modules); i++) {
-        msg = realloc(msg, strlen(modules[i]->name) + strlen(", ") + 1);
-        memcpy(msg + msg_len, modules[i]->name, strlen(modules[i]->name));
-        msg_len += strlen(modules[i]->name);
-        memcpy(msg + msg_len, ", ", strlen(", "));
-        msg_len += strlen(", ");
-
-        free(modules[i]);
-      }
-    }
-    default: {
-      msg[0] = DAEMON_SET_ERROR_INFO;
-
-      msg = realloc(msg, strlen("Invalid root implementation") + 1);
-      memcpy(msg + 1, "Invalid root implementation", strlen("Invalid root implementation"));
-    }
-  }
-
-  msg = realloc(msg, msg_len + 1);
-  msg[msg_len] = '\0';
-
-  unix_datagram_sendto(CONTROLLER_SOCKET, msg);
-
-  int socket_fd = create_daemon_socket();
-  if (socket_fd == -1) {
-    printf("Failed creating daemon socket: %s\n", strerror(errno));
-
-    return;
-  }
-
-  while (1) {
-    struct sockaddr_un addr;
-    socklen_t addr_len = sizeof(addr);
-    int client_fd = accept(socket_fd, (struct sockaddr *) &addr, &addr_len);
-    if (client_fd == -1) {
-      printf("Failed accepting client: %s\n", strerror(errno));
-
-      return;
-    }
-
-    char action;
-    read(client_fd, &action, 1);
-
-    switch (action) {
-      case DAEMON_PING_HEARTBEAT: {
-        char value = ZYGOTE_INJECTED;
-        unix_datagram_sendto(CONTROLLER_SOCKET, &value);
-      }
-      case DAEMON_ZYGOTE_RESTART: {
-        printf("Zygote restarted, clean up companions\n");
-
-        free_modules(modules);
-
-        /* companion code */
-      }
-      case DAEMON_SYSTEM_SERVER_STARTED: {
-        char value = SYSTEM_SERVER_STARTED;
-        unix_datagram_sendto(CONTROLLER_SOCKET, &value);
-      }
-      default: {
-        // WIP
-      }
-    }
-  }
-}
-
-void spawn_companion(char *name, int lib_fd) {
-  /* Creates 2 connected unix streams */
-  int sockets[2];
-  socketpair(AF_UNIX, SOCK_STREAM, 0, sockets);
-
-  int daemon_fd = sockets[0];
-  int companion_fd = sockets[1];
-
-  pid_t pid = fork();
-  if (pid == -1) {
-    printf("Failed forking: %s\n", strerror(errno));
-
-    return;
-  } else if (pid > 0) {
-    close(companion_fd);
-  
-    int status;
-    waitpid(pid, &status, 0);
-
-    if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
-      write(daemon_fd, name, strlen(name));
-      write(daemon_fd, &lib_fd, sizeof(lib_fd));
-
-      int response;
-      read(daemon_fd, &response, 1);
-
-      if (response == 0) {
-        printf("No companion spawned for %s because it has no entry\n", name);
-      } else if (response == 1) {
-        printf("Spawned companion for %s\n", name);
-      } else {
-        printf("Invalid companion response\n");
-      }
-    } else {
-      printf("Exited with status %d\n", status);
-    }
-  } else {
-    fcntl(companion_fd, F_SETFD, 0);
-  }
-
-  char *args[] = { "zygiskd", "companion", companion_fd, NULL };
-  execv("/system/bin/zygiskd", args);
-
-  exit(0);
-}
-
-void handle_daemon_action(enum DaemonSocketAction action, int stream_fd, struct Context *context) {
-  switch (action) {
-    case RequestLogcatFd: {
-      while (1) {
-        char level;
-        read(stream_fd, &level, 1);
-
-        char tag[PATH_MAX];
-        read(stream_fd, tag, PATH_MAX);
-
-        char message[PATH_MAX];
-        read(stream_fd, message, PATH_MAX);
-
-        __android_log_print(level, tag, message);
-      }
-    }
-    case GetProcessFlags: {
-      int uid;
-      read(stream_fd, &uid, sizeof(uid));
-
-      int flags = 0;
-      if (uid_is_manager(uid)) {
-        flags |= PROCESS_IS_MANAGER;
-      } else {
-        if (uid_granted_root(uid)) {
-          flags |= PROCESS_GRANTED_ROOT;
-        }
-        if (uid_should_umount(uid)) {
-          flags |= PROCESS_ON_DENYLIST;
-        }
-      }
-
-      switch (get_impl()) {
-        case KernelSU: {
-          flags |= PROCESS_ROOT_IS_KSU;
-        }
-        // case Magisk: {
-        //   flags |= PROCESS_ROOT_IS_MAGISK;
-        // }
-        // case APatch: {
-        //   flags |= PROCESS_ROOT_IS_APATCH;
-        // }
-      }
-
-      write(stream_fd, &flags, sizeof(flags));
-    }
-    case GetInfo: {
-      int flags = 0;
-
-      switch (get_impl()) {
-        case KernelSU: {
-          flags |= PROCESS_ROOT_IS_KSU;
-        }
-        // case Magisk: {
-        //   flags |= PROCESS_ROOT_IS_MAGISK;
-        // }
-        // case APatch: {
-        //   flags |= PROCESS_ROOT_IS_APATCH;
-        // }
-      }
-
-      write(stream_fd, &flags, sizeof(flags));
-
-      int pid = getpid();
-      write(stream_fd, &pid, sizeof(pid));
-    }
-    case ReadModules: {
-      int len = sizeof(context->modules);
-      write(stream_fd, &len, sizeof(len));
-
-      for (int i = 0; i < len; i++) {
-        write(stream_fd, context->modules[i]->name, strlen(context->modules[i]->name));
-        send_fd(stream_fd, context->modules[i]->lib_fd);
-      }
-    }
-    case RequestCompanionSocket: {
-      /* WIP */
-
-      break;
-    }
-    case GetModuleDir: {
-      int index;
-      read(stream_fd, &index, sizeof(index));
-
-      char dir[PATH_MAX];
-      snprintf(dir, PATH_MAX, "%s/%s", PATH_MODULES_DIR, context->modules[index]->name);
-      int dir_fd = open(dir, O_RDONLY);
-
-      send_fd(stream_fd, dir_fd);
-    }
-    default: {
-      // WIP
-    }
-  }
-}
-