Add a platform-specific syscall number iterator.

content/common/sandbox_seccomp_bpf_linux.cc

 // Copyright (c) 2012 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 <asm/unistd.h>
 #include <dlfcn.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <linux/audit.h>
 #include <linux/filter.h>
@@ skipping 1277 matching lines @@
       if (IsSystemVSharedMemory(sysno))
         return ErrorCode(ErrorCode::ERR_ALLOWED);
 #endif
 
       // Default on the baseline policy.
       return BaselinePolicy_x86_64(sysno);
   }
 }
 
 ErrorCode BlacklistDebugAndNumaPolicy(int sysno) {
-  if (sysno < static_cast<int>(MIN_SYSCALL) ||
-      sysno > static_cast<int>(MAX_SYSCALL)) {
+  if (!Sandbox::isValidSyscallNumber(sysno)) {
     // TODO(jln) we should not have to do that in a trivial policy.
     return ErrorCode(ENOSYS);
   }
 
   if (IsDebug(sysno) || IsNuma(sysno))
     return Sandbox::Trap(CrashSIGSYS_Handler, NULL);
 
   return ErrorCode(ErrorCode::ERR_ALLOWED);
 }
 
 // Allow all syscalls.
 // This will still deny x32 or IA32 calls in 64 bits mode or
 // 64 bits system calls in compatibility mode.
 ErrorCode AllowAllPolicy(int sysno) {
-  if (sysno < static_cast<int>(MIN_SYSCALL) ||
-      sysno > static_cast<int>(MAX_SYSCALL)) {
+  if (!Sandbox::isValidSyscallNumber(sysno)) {
     // TODO(jln) we should not have to do that in a trivial policy.
     return ErrorCode(ENOSYS);
   } else {
     return ErrorCode(ErrorCode::ERR_ALLOWED);
   }
 }
 
 // Warms up/preloads resources needed by the policies.
 void WarmupPolicy(Sandbox::EvaluateSyscall policy) {
 #if defined(__x86_64__)
@@ skipping 87 matching lines @@
 #if defined(__arm__)
   // We disable the sandbox on ARM for now until crbug.com/148856 is fixed.
   return false;
 #else
   const CommandLine& command_line = *CommandLine::ForCurrentProcess();
   if (process_type == switches::kGpuProcess)
     return !command_line.HasSwitch(switches::kDisableGpuSandbox);
 
   return true;
 #endif  // __arm__
-#endif  // process_type
+#endif  // SECCOMP_BPF_SANDBOX
   return false;
 }
 
 bool SandboxSeccompBpf::SupportsSandbox() {
 #if defined(SECCOMP_BPF_SANDBOX)
   // TODO(jln): pass the saved proc_fd_ from the LinuxSandbox singleton
   // here.
   if (Sandbox::supportsSeccompSandbox(-1) ==
       Sandbox::STATUS_AVAILABLE) {
     return true;
@@ skipping 10 matching lines @@
       // Process-specific policy.
       ShouldEnableSeccompBpf(process_type) &&
       SupportsSandbox()) {
     return StartBpfSandbox(command_line, process_type);
   }
 #endif
   return false;
 }
 
 }  // namespace content