Restructure project files

native/src/core/zygisk/entry.cpp

@@ -0,0 +1,205 @@
+#include <libgen.h>
+#include <dlfcn.h>
+#include <sys/prctl.h>
+#include <sys/mount.h>
+#include <android/log.h>
+#include <android/dlext.h>
+
+#include <base.hpp>
+#include <consts.hpp>
+
+#include "zygisk.hpp"
+#include "module.hpp"
+
+using namespace std;
+
+void *self_handle = nullptr;
+
+extern "C" [[maybe_unused]] void zygisk_inject_entry(void *handle) {
+    self_handle = handle;
+    zygisk_logging();
+    hook_functions();
+    ZLOGD("load success\n");
+}
+
+// The following code runs in zygote/app process
+
+static inline bool should_load_modules(uint32_t flags) {
+    return (flags & UNMOUNT_MASK) != UNMOUNT_MASK &&
+           (flags & PROCESS_IS_MAGISK_APP) != PROCESS_IS_MAGISK_APP;
+}
+
+int remote_get_info(int uid, const char *process, uint32_t *flags, vector<int> &fds) {
+    if (int fd = zygisk_request(ZygiskRequest::GET_INFO); fd >= 0) {
+        write_int(fd, uid);
+        write_string(fd, process);
+        xxread(fd, flags, sizeof(*flags));
+        if (should_load_modules(*flags)) {
+            fds = recv_fds(fd);
+        }
+        return fd;
+    }
+    return -1;
+}
+
+// The following code runs in magiskd
+
+static vector<int> get_module_fds(bool is_64_bit) {
+    vector<int> fds;
+    // All fds passed to send_fds have to be valid file descriptors.
+    // To workaround this issue, send over STDOUT_FILENO as an indicator of an
+    // invalid fd as it will always be /dev/null in magiskd
+    if (is_64_bit) {
+#if defined(__LP64__)
+        std::transform(module_list->begin(), module_list->end(), std::back_inserter(fds),
+            [](const module_info &info) { return info.z64 < 0 ? STDOUT_FILENO : info.z64; });
+#endif
+    } else {
+        std::transform(module_list->begin(), module_list->end(), std::back_inserter(fds),
+            [](const module_info &info) { return info.z32 < 0 ? STDOUT_FILENO : info.z32; });
+    }
+    return fds;
+}
+
+static bool get_exe(int pid, char *buf, size_t sz) {
+    char exe[128];
+    if (ssprintf(exe, sizeof(exe), "/proc/%d/exe", pid) < 0)
+        return false;
+    return xreadlink(exe, buf, sz) > 0;
+}
+
+static pthread_mutex_t zygiskd_lock = PTHREAD_MUTEX_INITIALIZER;
+static int zygiskd_sockets[] = { -1, -1 };
+#define zygiskd_socket zygiskd_sockets[is_64_bit]
+
+static void connect_companion(int client, bool is_64_bit) {
+    mutex_guard g(zygiskd_lock);
+
+    if (zygiskd_socket >= 0) {
+        // Make sure the socket is still valid
+        pollfd pfd = { zygiskd_socket, 0, 0 };
+        poll(&pfd, 1, 0);
+        if (pfd.revents) {
+            // Any revent means error
+            close(zygiskd_socket);
+            zygiskd_socket = -1;
+        }
+    }
+    if (zygiskd_socket < 0) {
+        int fds[2];
+        socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0, fds);
+        zygiskd_socket = fds[0];
+        if (fork_dont_care() == 0) {
+            char exe[64];
+            ssprintf(exe, sizeof(exe), "%s/magisk%s", get_magisk_tmp(), (is_64_bit ? "64" : "32"));
+            // This fd has to survive exec
+            fcntl(fds[1], F_SETFD, 0);
+            char buf[16];
+            ssprintf(buf, sizeof(buf), "%d", fds[1]);
+            execl(exe, "", "zygisk", "companion", buf, (char *) nullptr);
+            exit(-1);
+        }
+        close(fds[1]);
+        vector<int> module_fds = get_module_fds(is_64_bit);
+        send_fds(zygiskd_socket, module_fds.data(), module_fds.size());
+        // Wait for ack
+        if (read_int(zygiskd_socket) != 0) {
+            LOGE("zygiskd startup error\n");
+            return;
+        }
+    }
+    send_fd(zygiskd_socket, client);
+}
+
+extern bool uid_granted_root(int uid);
+static void get_process_info(int client, const sock_cred *cred) {
+    int uid = read_int(client);
+    string process = read_string(client);
+
+    uint32_t flags = 0;
+
+    check_pkg_refresh();
+    if (is_deny_target(uid, process)) {
+        flags |= PROCESS_ON_DENYLIST;
+    }
+    int manager_app_id = get_manager();
+    if (to_app_id(uid) == manager_app_id) {
+        flags |= PROCESS_IS_MAGISK_APP;
+    }
+    if (denylist_enforced) {
+        flags |= DENYLIST_ENFORCING;
+    }
+    if (uid_granted_root(uid)) {
+        flags |= PROCESS_GRANTED_ROOT;
+    }
+
+    xwrite(client, &flags, sizeof(flags));
+
+    if (should_load_modules(flags)) {
+        char buf[256];
+        if (!get_exe(cred->pid, buf, sizeof(buf))) {
+            LOGW("zygisk: remote process %d probably died, abort\n", cred->pid);
+            send_fd(client, -1);
+            return;
+        }
+        vector<int> fds = get_module_fds(str_ends(buf, "64"));
+        send_fds(client, fds.data(), fds.size());
+    }
+
+    if (uid != 1000 || process != "system_server")
+        return;
+
+    // Collect module status from system_server
+    int slots = read_int(client);
+    dynamic_bitset bits;
+    for (int i = 0; i < slots; ++i) {
+        dynamic_bitset::slot_type l = 0;
+        xxread(client, &l, sizeof(l));
+        bits.emplace_back(l);
+    }
+    for (int id = 0; id < module_list->size(); ++id) {
+        if (!as_const(bits)[id]) {
+            // Either not a zygisk module, or incompatible
+            char buf[4096];
+            ssprintf(buf, sizeof(buf), MODULEROOT "/%s/zygisk",
+                module_list->operator[](id).name.data());
+            if (int dirfd = open(buf, O_RDONLY | O_CLOEXEC); dirfd >= 0) {
+                close(xopenat(dirfd, "unloaded", O_CREAT | O_RDONLY, 0644));
+                close(dirfd);
+            }
+        }
+    }
+}
+
+static void get_moddir(int client) {
+    int id = read_int(client);
+    char buf[4096];
+    ssprintf(buf, sizeof(buf), MODULEROOT "/%s", module_list->operator[](id).name.data());
+    int dfd = xopen(buf, O_RDONLY | O_CLOEXEC);
+    send_fd(client, dfd);
+    close(dfd);
+}
+
+void zygisk_handler(int client, const sock_cred *cred) {
+    int code = read_int(client);
+    char buf[256];
+    switch (code) {
+    case ZygiskRequest::GET_INFO:
+        get_process_info(client, cred);
+        break;
+    case ZygiskRequest::CONNECT_COMPANION:
+        if (get_exe(cred->pid, buf, sizeof(buf))) {
+            connect_companion(client, str_ends(buf, "64"));
+        } else {
+            LOGW("zygisk: remote process %d probably died, abort\n", cred->pid);
+        }
+        break;
+    case ZygiskRequest::GET_MODDIR:
+        get_moddir(client);
+        break;
+    default:
+        // Unknown code
+        break;
+    }
+    close(client);
+}