Fork of the Android NDK crazy linker.

third_party/android_crazy_linker/src/tests/test_shared_relro.cpp

+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// A crazy linker test to:
+// - Load a library (libfoo.so) with the linker.
+// - Find the address of the "Foo" function in it.
+// - Call the function.
+// - Close the library.
+
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/socket.h>
+#include <sys/uio.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include <crazy_linker.h>
+
+#include "test_util.h"
+
+typedef void (*FunctionPtr)();
+
+int main() {
+
+  if (!crazy_system_can_share_relro()) {
+    fprintf(stderr, "WARNING: Test ignored due to broken kernel!!\n");
+    return 0;
+  }
+
+  crazy_context_t* context = crazy_context_create();
+
+  RelroLibrary foo;
+
+  // Load at fixed address to simplify testing.
+  crazy_context_set_load_address(context, 0x20000000);
+  foo.Init("libfoo_with_relro.so", context);
+
+  printf("Library loaded\n");
+
+  int pipes[2];
+  if (socketpair(AF_UNIX, SOCK_STREAM, 0, pipes) < 0)
+    Panic("Could not create socket pair: %s", strerror(errno));
+
+  pid_t child = fork();
+  if (child < 0)
+    Panic("Could not fork test program!");
+
+  if (child == 0) {
+    // In the child.
+    printf("Child waiting for foo relro fd\n");
+
+    foo.ReceiveRelroInfo(pipes[0]);
+    foo.UseSharedRelro(context);
+
+    printf("RELRO used in child process\n");
+
+    CheckRelroMaps(1);
+
+    FunctionPtr foo_func;
+    if (!crazy_library_find_symbol(
+             foo.library, "Foo", reinterpret_cast<void**>(&foo_func)))
+      Panic("Could not find 'Foo' in library");
+
+    printf("Calling Foo()\n");
+    (*foo_func)();
+
+    printf("Foo called, exiting\n");
+
+    exit(0);
+
+  } else {
+    // In the parent.
+
+    printf("Parent enabling foo RELRO sharing\n");
+
+    foo.EnableSharedRelro(context);
+    foo.SendRelroInfo(pipes[1]);
+
+    printf("RELRO enabled and sent to child\n");
+
+    CheckRelroMaps(1);
+
+    printf("Parent waiting for child\n");
+
+    // Wait for child to complete.
+    int status;
+    waitpid(child, &status, 0);
+
+    if (WIFSIGNALED(status))
+      Panic("Child terminated by signal!!\n");
+    else if (WIFEXITED(status)) {
+      int child_status = WEXITSTATUS(status);
+      if (child_status != 0)
+        Panic("Child terminated with status=%d\n", child_status);
+    } else
+      Panic("Child exited for unknown reason!!\n");
+  }
+
+  crazy_context_destroy(context);
+  return 0;
+}