Index: sandbox/linux/bpf_dsl/policy_compiler.cc |
diff --git a/sandbox/linux/bpf_dsl/policy_compiler.cc b/sandbox/linux/bpf_dsl/policy_compiler.cc |
index bcfd21b77658d9abc8bb1abd4260b66b7f12fd23..9d94968b0af22073d1540332e4fb24d772421639 100644 |
--- a/sandbox/linux/bpf_dsl/policy_compiler.cc |
+++ b/sandbox/linux/bpf_dsl/policy_compiler.cc |
@@ -18,7 +18,6 @@ |
#include "sandbox/linux/bpf_dsl/policy.h" |
#include "sandbox/linux/bpf_dsl/seccomp_macros.h" |
#include "sandbox/linux/bpf_dsl/syscall_set.h" |
-#include "sandbox/linux/seccomp-bpf/die.h" |
#include "sandbox/linux/seccomp-bpf/errorcode.h" |
#include "sandbox/linux/system_headers/linux_seccomp.h" |
@@ -96,35 +95,21 @@ PolicyCompiler::~PolicyCompiler() { |
} |
scoped_ptr<CodeGen::Program> PolicyCompiler::Compile() { |
- if (!policy_->InvalidSyscall()->IsDeny()) { |
- SANDBOX_DIE("Policies should deny invalid system calls."); |
- } |
+ CHECK(policy_->InvalidSyscall()->IsDeny()) |
+ << "Policies should deny invalid system calls"; |
// If our BPF program has unsafe traps, enable support for them. |
if (has_unsafe_traps_) { |
- // As support for unsafe jumps essentially defeats all the security |
- // measures that the sandbox provides, we print a big warning message -- |
- // and of course, we make sure to only ever enable this feature if it |
- // is actually requested by the sandbox policy. |
- |
CHECK_NE(0U, escapepc_) << "UnsafeTrap() requires a valid escape PC"; |
for (int sysnum : kSyscallsRequiredForUnsafeTraps) { |
- if (!policy_->EvaluateSyscall(sysnum)->IsAllow()) { |
- SANDBOX_DIE( |
- "Policies that use UnsafeTrap() must unconditionally allow all " |
- "required system calls"); |
- } |
+ CHECK(policy_->EvaluateSyscall(sysnum)->IsAllow()) |
+ << "Policies that use UnsafeTrap() must unconditionally allow all " |
+ "required system calls"; |
} |
- if (!registry_->EnableUnsafeTraps()) { |
- // We should never be able to get here, as UnsafeTrap() should never |
- // actually return a valid ErrorCode object unless the user set the |
- // CHROME_SANDBOX_DEBUGGING environment variable; and therefore, |
- // "has_unsafe_traps" would always be false. But better double-check |
- // than enabling dangerous code. |
- SANDBOX_DIE("We'd rather die than enable unsafe traps"); |
- } |
+ CHECK(registry_->EnableUnsafeTraps()) |
+ << "We'd rather die than enable unsafe traps"; |
} |
// Assemble the BPF filter program. |
@@ -261,9 +246,9 @@ CodeGen::Node PolicyCompiler::AssembleJumpTable(Ranges::const_iterator start, |
// a binary search over the ranges. |
// As a sanity check, we need to have at least one distinct ranges for us |
// to be able to build a jump table. |
- if (stop - start <= 0) { |
- SANDBOX_DIE("Invalid set of system call ranges"); |
- } else if (stop - start == 1) { |
+ CHECK(start < stop) << "Invalid iterator range"; |
+ const auto n = stop - start; |
+ if (n == 1) { |
// If we have narrowed things down to a single range object, we can |
// return from the BPF filter program. |
return start->node; |
@@ -273,7 +258,7 @@ CodeGen::Node PolicyCompiler::AssembleJumpTable(Ranges::const_iterator start, |
// We compare our system call number against the lowest valid system call |
// number in this range object. If our number is lower, it is outside of |
// this range object. If it is greater or equal, it might be inside. |
- Ranges::const_iterator mid = start + (stop - start) / 2; |
+ Ranges::const_iterator mid = start + n / 2; |
// Sub-divide the list of ranges and continue recursively. |
CodeGen::Node jf = AssembleJumpTable(start, mid); |
@@ -293,31 +278,30 @@ CodeGen::Node PolicyCompiler::RetExpression(const ErrorCode& err) { |
case ErrorCode::ET_TRAP: |
return gen_.MakeInstruction(BPF_RET + BPF_K, err.err()); |
default: |
- SANDBOX_DIE("ErrorCode is not suitable for returning from a BPF program"); |
+ LOG(FATAL) |
+ << "ErrorCode is not suitable for returning from a BPF program"; |
+ return CodeGen::kNullNode; |
} |
} |
CodeGen::Node PolicyCompiler::CondExpression(const ErrorCode& cond) { |
// Sanity check that |cond| makes sense. |
- if (cond.argno_ < 0 || cond.argno_ >= 6) { |
- SANDBOX_DIE("sandbox_bpf: invalid argument number"); |
- } |
- if (cond.width_ != ErrorCode::TP_32BIT && |
- cond.width_ != ErrorCode::TP_64BIT) { |
- SANDBOX_DIE("sandbox_bpf: invalid argument width"); |
- } |
- if (cond.mask_ == 0) { |
- SANDBOX_DIE("sandbox_bpf: zero mask is invalid"); |
- } |
- if ((cond.value_ & cond.mask_) != cond.value_) { |
- SANDBOX_DIE("sandbox_bpf: value contains masked out bits"); |
+ CHECK(cond.argno_ >= 0 && cond.argno_ < 6) << "Invalid argument number " |
+ << cond.argno_; |
+ CHECK(cond.width_ == ErrorCode::TP_32BIT || |
+ cond.width_ == ErrorCode::TP_64BIT) |
+ << "Invalid argument width " << cond.width_; |
+ CHECK_NE(0U, cond.mask_) << "Zero mask is invalid"; |
+ CHECK_EQ(cond.value_, cond.value_ & cond.mask_) |
+ << "Value contains masked out bits"; |
+ if (sizeof(void*) == 4) { |
+ CHECK_EQ(ErrorCode::TP_32BIT, cond.width_) |
+ << "Invalid width on 32-bit platform"; |
} |
- if (cond.width_ == ErrorCode::TP_32BIT && |
- ((cond.mask_ >> 32) != 0 || (cond.value_ >> 32) != 0)) { |
- SANDBOX_DIE("sandbox_bpf: test exceeds argument size"); |
+ if (cond.width_ == ErrorCode::TP_32BIT) { |
+ CHECK_EQ(0U, cond.mask_ >> 32) << "Mask exceeds argument size"; |
+ CHECK_EQ(0U, cond.value_ >> 32) << "Value exceeds argument size"; |
} |
- // TODO(mdempsky): Reject TP_64BIT on 32-bit platforms. For now we allow it |
- // because some SandboxBPF unit tests exercise it. |
jln (very slow on Chromium)
2015/02/20 07:00:44
So these disappeared? Cool, but I don't remember :
|
CodeGen::Node passed = RetExpression(*cond.passed_); |
CodeGen::Node failed = RetExpression(*cond.failed_); |