1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef SANDBOX_LINUX_SECCOMP_BPF_SYSCALL_ITERATOR_H__ 6 #define SANDBOX_LINUX_SECCOMP_BPF_SYSCALL_ITERATOR_H__ 7 8 #include <stdint.h> 9 10 #include "base/basictypes.h" 11 12 namespace sandbox { 13 14 // Iterates over the entire system call range from 0..0xFFFFFFFFu. This 15 // iterator is aware of how system calls look like and will skip quickly 16 // over ranges that can't contain system calls. It iterates more slowly 17 // whenever it reaches a range that is potentially problematic, returning 18 // the last invalid value before a valid range of system calls, and the 19 // first invalid value after a valid range of syscalls. It iterates over 20 // individual values whenever it is in the normal range for system calls 21 // (typically MIN_SYSCALL..MAX_SYSCALL). 22 // If |invalid_only| is true, this iterator will only return invalid 23 // syscall numbers, but will still skip quickly over invalid ranges, 24 // returning the first invalid value in the range and then skipping 25 // to the last invalid value in the range. 26 // 27 // Example usage: 28 // for (SyscallIterator iter(false); !iter.Done(); ) { 29 // uint32_t sysnum = iter.Next(); 30 // // Do something with sysnum. 31 // } 32 // 33 // TODO(markus): Make this a classic C++ iterator. 34 class SyscallIterator { 35 public: SyscallIterator(bool invalid_only)36 explicit SyscallIterator(bool invalid_only) 37 : invalid_only_(invalid_only), done_(false), num_(0) {} 38 Done()39 bool Done() const { return done_; } 40 uint32_t Next(); 41 static bool IsValid(uint32_t num); 42 43 private: 44 static bool IsArmPrivate(uint32_t num); 45 46 bool invalid_only_; 47 bool done_; 48 uint32_t num_; 49 50 DISALLOW_IMPLICIT_CONSTRUCTORS(SyscallIterator); 51 }; 52 53 } // namespace sandbox 54 55 #endif // SANDBOX_LINUX_SECCOMP_BPF_SYSCALL_ITERATOR_H__ 56