Initial implementation of the Mac Bootstrap Sandbox.

sandbox/mac/os_compatibility.cc

+// Copyright 2014 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.
+
+#include "sandbox/mac/os_compatibility.h"
+
+#include <servers/bootstrap.h>
+#include <unistd.h>
+
+#include "base/mac/mac_util.h"
+
+namespace sandbox {
+
+namespace {
+
+// Verified from launchd-329.3.3 (10.6.8).
+struct look_up2_request_10_6 {
+  mach_msg_header_t Head;
+  NDR_record_t NDR;
+  name_t servicename;
+  pid_t targetpid;
+  uint64_t flags;
+};
+
+struct look_up2_reply_10_6 {
+  mach_msg_header_t Head;
+  mach_msg_body_t msgh_body;
+  mach_msg_port_descriptor_t service_port;
+};
+
+// Verified from:
+//   launchd-392.39 (10.7.5)
+//   launchd-442.26.2 (10.8.5)
+//   launchd-842.1.4 (10.9.0)
+struct look_up2_request_10_7 {
+  mach_msg_header_t Head;
+  NDR_record_t NDR;
+  name_t servicename;
+  pid_t targetpid;
+  uuid_t instanceid;
+  uint64_t flags;
+};
+
+// look_up2_reply_10_7 is the same as the 10_6 version.
+
+// TODO(rsesek): Libc provides strnlen() starting in 10.7.
+size_t strnlen(const char* str, size_t maxlen) {
+  size_t len = 0;
+  for (; len < maxlen; ++len, ++str) {
+    if (*str == '\0')
+      break;
+  }
+  return len;
+}
+
+template <typename R>
+std::string LaunchdLookUp2GetRequestName(const mach_msg_header_t* header) {
+  DCHECK_EQ(sizeof(R), header->msgh_size);
+  const R* request = reinterpret_cast<const R*>(header);
+  // Make sure the name is properly NUL-terminated.
+  const size_t name_length =
+      strnlen(request->servicename, BOOTSTRAP_MAX_NAME_LEN);
+  std::string name = std::string(request->servicename, name_length);
+  return name;
+}
+
+template <typename R>
+void LaunchdLookUp2FillReply(mach_msg_header_t* header, mach_port_t port) {
+  R* reply = reinterpret_cast<R*>(header);
+  reply->Head.msgh_size = sizeof(R);
+  reply->Head.msgh_bits =
+      MACH_MSGH_BITS_REMOTE(MACH_MSG_TYPE_MOVE_SEND_ONCE) |
+      MACH_MSGH_BITS_COMPLEX;
+  reply->msgh_body.msgh_descriptor_count = 1;
+  reply->service_port.name = port;
+  reply->service_port.disposition = MACH_MSG_TYPE_PORT_SEND;
+  reply->service_port.type = MACH_MSG_PORT_DESCRIPTOR;
+}
+
+}  // namespace
+
+const LaunchdCompatibilityShim GetLaunchdCompatibilityShim() {
+  LaunchdCompatibilityShim shim = {
+    .msg_id_look_up2 = 404,
+    .msg_id_swap_integer = 416,
+    .look_up2_fill_reply = &LaunchdLookUp2FillReply<look_up2_reply_10_6>
+  };
+
+  if (base::mac::IsOSSnowLeopard()) {
+    shim.look_up2_get_request_name =
+        &LaunchdLookUp2GetRequestName<look_up2_request_10_6>;
+  } else if (base::mac::IsOSLionOrLater() &&
+             !base::mac::IsOSLaterThanMavericks_DontCallThis()) {
+    shim.look_up2_get_request_name =
+        &LaunchdLookUp2GetRequestName<look_up2_request_10_7>;
+  } else {
+    DLOG(ERROR) << "Unknown OS, using launchd compatibility shim from 10.7.";
+    shim.look_up2_get_request_name =
+        &LaunchdLookUp2GetRequestName<look_up2_request_10_7>;
+  }
+
+  return shim;
+}
+
+}  // namespace sandbox