Merge remote-tracking branch 'cern/multiuser-regression-v1' into cm-11.0

[android-x86/external-koush-Superuser.git] / Superuser / jni / su / su.c

diff --git a/Superuser/jni/su/su.c b/Superuser/jni/su/su.c
index 6cbe724..55e54a6 100644 (file)
--- a/Superuser/jni/su/su.c
+++ b/Superuser/jni/su/su.c
@@ -17,6 +17,7 @@
 
 #include <sys/types.h>
 #include <sys/socket.h>
+#include <sys/uio.h>
 #include <sys/un.h>
 #include <sys/wait.h>
 #include <sys/select.h>
@@ -81,48 +82,31 @@ int fork_zero_fucks() {
     }
 }
 
-void exec_log(char *priority, char* logline) {
-  int pid;
-  if ((pid = fork()) == 0) {
-      int null = open("/dev/null", O_WRONLY | O_CLOEXEC);
-      dup2(null, STDIN_FILENO);
-      dup2(null, STDOUT_FILENO);
-      dup2(null, STDERR_FILENO);
-      execl("/system/bin/log", "/system/bin/log", "-p", priority, "-t", LOG_TAG, logline, NULL);
-      _exit(0);
-  }
-  int status;
-  waitpid(pid, &status, 0);
-}
-
-void exec_loge(const char* fmt, ...) {
+void exec_log(int priority, const char* fmt, ...) {
+    static int log_fd = -1;
+    struct iovec vec[3];
     va_list args;
+    char msg[PATH_MAX];
 
-    char logline[PATH_MAX];
-    va_start(args, fmt);
-    vsnprintf(logline, PATH_MAX, fmt, args);
-    va_end(args);
-    exec_log("e", logline);
-}
-
-void exec_logw(const char* fmt, ...) {
-    va_list args;
+    if (log_fd < 0) {
+        log_fd = open("/dev/log/main", O_WRONLY);
+        if (log_fd < 0) {
+            return;
+        }
+    }
 
-    char logline[PATH_MAX];
     va_start(args, fmt);
-    vsnprintf(logline, PATH_MAX, fmt, args);
+    vsnprintf(msg, PATH_MAX, fmt, args);
     va_end(args);
-    exec_log("w", logline);
-}
 
-void exec_logd(const char* fmt, ...) {
-    va_list args;
+    vec[0].iov_base   = (unsigned char *) &priority;
+    vec[0].iov_len    = 1;
+    vec[1].iov_base   = (void *) LOG_TAG;
+    vec[1].iov_len    = strlen(LOG_TAG) + 1;
+    vec[2].iov_base   = (void *) msg;
+    vec[2].iov_len    = strlen(msg) + 1;
 
-    char logline[PATH_MAX];
-    va_start(args, fmt);
-    vsnprintf(logline, PATH_MAX, fmt, args);
-    va_end(args);
-    exec_log("d", logline);
+    writev(log_fd, vec, 3);
 }
 
 static int from_init(struct su_initiator *from) {
@@ -427,7 +411,7 @@ do {                                        \
 static int socket_receive_result(int fd, char *result, ssize_t result_len) {
     ssize_t len;
 
-    LOGD("waiting for user");
+    LOGV("waiting for user");
     len = read(fd, result, result_len-1);
     if (len < 0) {
         PLOGE("read(result)");
@@ -559,6 +543,9 @@ static __attribute__ ((noreturn)) void allow(struct su_context *ctx) {
  * Find the properties ourselves.
  */
 int access_disabled(const struct su_initiator *from) {
+#ifndef SUPERUSER_EMBEDDED
+    return 0;
+#else
     char *data;
     char build_type[PROPERTY_VALUE_MAX];
     char debuggable[PROPERTY_VALUE_MAX], enabled[PROPERTY_VALUE_MAX];
@@ -608,30 +595,51 @@ int access_disabled(const struct su_initiator *from) {
 
     }
     return 0;
+#endif
 }
 
-static int is_api_18() {
+static int get_api_version() {
   char sdk_ver[PROPERTY_VALUE_MAX];
   char *data = read_file("/system/build.prop");
   get_property(data, sdk_ver, "ro.build.version.sdk", "0");
   int ver = atoi(sdk_ver);
   free(data);
-  return ver >= 18;
+  return ver;
+}
+
+static void fork_for_samsung(void)
+{
+    // Samsung CONFIG_SEC_RESTRICT_SETUID wants the parent process to have
+    // EUID 0, or else our setresuid() calls will be denied.  So make sure
+    // all such syscalls are executed by a child process.
+    int rv;
+
+    switch (fork()) {
+    case 0:
+        return;
+    case -1:
+        PLOGE("fork");
+        exit(1);
+    default:
+        if (wait(&rv) < 0) {
+            exit(1);
+        } else {
+            exit(WEXITSTATUS(rv));
+        }
+    }
 }
 
 int main(int argc, char *argv[]) {
+    return su_main(argc, argv, 1);
+}
+
+int su_main(int argc, char *argv[], int need_client) {
     // start up in daemon mode if prompted
     if (argc == 2 && strcmp(argv[1], "--daemon") == 0) {
         return run_daemon();
     }
 
-    // attempt to use the daemon client if not root,
-    // or this is api 18 and adb shell (/data is not readable even as root)
-    if ((geteuid() != AID_ROOT && getuid() != AID_ROOT) || (is_api_18() && getuid() == AID_SHELL)) {
-        // attempt to connect to daemon...
-        LOGD("starting daemon client %d %d", getuid(), geteuid());
-        return connect_daemon(argc, argv);
-    }
+    fork_for_samsung();
 
     // Sanitize all secure environment variables (from linker_environ.c in AOSP linker).
     /* The same list than GLibc at this point */
@@ -766,6 +774,20 @@ int main(int argc, char *argv[]) {
             usage(2);
         }
     }
+
+    if (need_client) {
+        // attempt to use the daemon client if not root,
+        // or this is api 18 and adb shell (/data is not readable even as root)
+        // or just always use it on API 19+ (ART)
+        if ((geteuid() != AID_ROOT && getuid() != AID_ROOT) ||
+            (get_api_version() >= 18 && getuid() == AID_SHELL) ||
+            get_api_version() >= 19) {
+            // attempt to connect to daemon...
+            LOGD("starting daemon client %d %d", getuid(), geteuid());
+            return connect_daemon(argc, argv);
+        }
+    }
+
     if (optind < argc && !strcmp(argv[optind], "-")) {
         ctx.to.login = 1;
         optind++;