[MIPS] Add seccomp bpf support

sandbox/linux/seccomp-bpf/syscall_iterator_unittest.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 "sandbox/linux/seccomp-bpf/sandbox_bpf.h"
 #include "sandbox/linux/seccomp-bpf/syscall_iterator.h"
 #include "sandbox/linux/tests/unit_tests.h"
 
 namespace sandbox {
 
 namespace {
 
 SANDBOX_TEST(SyscallIterator, Monotonous) {
   for (int i = 0; i < 2; ++i) {
     bool invalid_only = !i;  // Testing both |invalid_only| cases.
     SyscallIterator iter(invalid_only);
     uint32_t next = iter.Next();
 
     if (!invalid_only) {
+#if defined(__mips__) && (_MIPS_SIM == _MIPS_SIM_ABI32)
+      // The iterator should start at 4000 for MIPS O32 ABI
+      SANDBOX_ASSERT(next == 4000);

[jln (very slow on Chromium), 2014/05/02 20:42:04]

This adds no value, we need to re-work these tests to make them compatible with
MIN_SYSCALL > 0.

[nedeljko, 2014/05/07 15:40:05]

Done.

+#else
       // The iterator should start at 0.
       SANDBOX_ASSERT(next == 0);

[jln (very slow on Chromium), 2014/05/02 20:42:04]

This should still hold on MIPS.

[nedeljko, 2014/05/07 15:40:05]

Done.

+#endif
     }
     for (uint32_t last = next; !iter.Done(); last = next) {
       next = iter.Next();
       SANDBOX_ASSERT(last < next);
     }
     // The iterator should always return 0xFFFFFFFFu as the last value.
     SANDBOX_ASSERT(next == 0xFFFFFFFFu);
   }
 }
 
 SANDBOX_TEST(SyscallIterator, PublicSyscallRange) {
   SyscallIterator iter(false);
   uint32_t next = iter.Next();
 
   // The iterator should cover the public syscall range
   // MIN_SYSCALL..MAX_PUBLIC_SYSCALL, without skipping syscalls.
-  // We're assuming MIN_SYSCALL == 0 for all architectures,
-  // this is currently valid for Intel and ARM EABI.
+  // We're assuming MIN_SYSCALL == 0 for all architectures
+  // (this is currently valid for Intel and ARM EABI), except for
+  // Mips O32 ABI for which MIN_SYSCALL == 4000 .
+#if defined(__mips__) && (_MIPS_SIM == _MIPS_SIM_ABI32)
+  SANDBOX_ASSERT(MIN_SYSCALL == 4000);
+#else
   SANDBOX_ASSERT(MIN_SYSCALL == 0);
+#endif
   SANDBOX_ASSERT(next == MIN_SYSCALL);
   for (uint32_t last = next; next < MAX_PUBLIC_SYSCALL + 1; last = next) {
     SANDBOX_ASSERT((next = iter.Next()) == last + 1);
   }
   SANDBOX_ASSERT(next == MAX_PUBLIC_SYSCALL + 1);
 }
 
 #if defined(__arm__)
 SANDBOX_TEST(SyscallIterator, ARMPrivateSyscallRange) {
   SyscallIterator iter(false);
@@ skipping 49 matching lines @@
     next = iter.Next();
     SANDBOX_ASSERT(iter.Done());
     SANDBOX_ASSERT(next == 0xFFFFFFFFu);
   }
 }
 
 SANDBOX_TEST(SyscallIterator, InvalidOnly) {
   bool invalid_only = true;
   SyscallIterator iter(invalid_only);
   uint32_t next = iter.Next();
-  // We're assuming MIN_SYSCALL == 0 for all architectures,
-  // this is currently valid for Intel and ARM EABI.
+  // We're assuming MIN_SYSCALL == 0 for all architectures
+  // (this is currently valid for Intel and ARM EABI), except
+  // for Mips O32 ABI for which MIN_SYSCALL == 4000.
   // First invalid syscall should then be |MAX_PUBLIC_SYSCALL + 1|.
+#if defined(__mips__) && (_MIPS_SIM == _MIPS_SIM_ABI32)
+  SANDBOX_ASSERT(MIN_SYSCALL == 4000);
+#else
   SANDBOX_ASSERT(MIN_SYSCALL == 0);
+#endif
   SANDBOX_ASSERT(next == MAX_PUBLIC_SYSCALL + 1);
 
 #if defined(__arm__)
   next = iter.Next();
   // The iterator should skip until the last invalid syscall in this range.
   SANDBOX_ASSERT(next == MIN_PRIVATE_SYSCALL - 1);
   while (next <= MAX_PRIVATE_SYSCALL) {
     next = iter.Next();
   }
 
   next = iter.Next();
   // The iterator should skip until the last invalid syscall in this range.
   SANDBOX_ASSERT(next == MIN_GHOST_SYSCALL - 1);
   while (next <= MAX_SYSCALL) {
     next = iter.Next();
   }
   SANDBOX_ASSERT(next == MAX_SYSCALL + 1);
 #endif
 }
 
 }  // namespace
 
 }  // namespace sandbox