[MIPS] Implementation of sel_ldr for MIPS architecture.

src/trusted/validator_mips/ncvalidate.cc

+/*
+ * Copyright (c) 2012 The Native Client 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 "native_client/src/trusted/validator_mips/ncvalidate.h"
+
+#include <vector>
+
+#include "native_client/src/include/nacl_string.h"
+#include "native_client/src/include/portability.h"
+#include "native_client/src/trusted/validator_mips/validator.h"
+#include "native_client/src/trusted/validator_mips/model.h"
+#include "native_client/src/trusted/validator/ncvalidate.h"
+

[Mark Seaborn, 2012/09/18 03:24:34]

Nit: remove empty line here to keep native_client #includes together

FYI, I have only skimmed this file because I'm less familiar with the ARM and
MIPS validators.  You might want to get whoever did the MIPS validator review
before to take a look if you want a more thorough review of this file.

+#include "native_client/src/trusted/service_runtime/arch/mips/sel_ldr_mips.h"
+
+using nacl_mips_val::SfiValidator;
+using nacl_mips_val::CodeSegment;
+using nacl_mips_dec::Register;
+using nacl_mips_dec::kRegisterStack;
+using nacl_mips_dec::kRegListReserved;
+using std::vector;
+
+
+class EarlyExitProblemSink : public nacl_mips_val::ProblemSink {
+ private:
+  bool problems_;
+
+ public:
+  EarlyExitProblemSink() : nacl_mips_val::ProblemSink(), problems_(false) {}
+
+  virtual void ReportProblem(uint32_t vaddr,
+                              nacl_mips_dec::SafetyLevel safety,
+                              const nacl::string &problem_code,
+                              uint32_t ref_vaddr) {
+    UNREFERENCED_PARAMETER(vaddr);
+    UNREFERENCED_PARAMETER(safety);
+    UNREFERENCED_PARAMETER(problem_code);
+    UNREFERENCED_PARAMETER(ref_vaddr);
+
+    problems_ = true;
+  }
+  virtual bool ShouldContinue() {
+    return !problems_;
+  }
+};
+
+
+class StuboutProblemSink : public nacl_mips_val::ProblemSink {
+ private:
+  bool problems_;
+  uint32_t const kNaClFullStop;
+
+ public:
+  StuboutProblemSink() : nacl_mips_val::ProblemSink(), problems_(false),
+                                             kNaClFullStop(NACL_HALT_OPCODE) {}
+
+  virtual void ReportProblem(uint32_t vaddr,
+                              nacl_mips_dec::SafetyLevel safety,
+                              const nacl::string &problem_code,
+                              uint32_t ref_vaddr) {
+    UNREFERENCED_PARAMETER(safety);
+    UNREFERENCED_PARAMETER(problem_code);
+    UNREFERENCED_PARAMETER(ref_vaddr);
+    stub_out_instr(vaddr);
+
+    problems_ = true;
+  }
+  virtual bool ShouldContinue() {
+    return true;
+  }
+
+ private:
+  void stub_out_instr(uint32_t vaddr) {
+#ifdef __BIG_ENDIAN__
+    assert(0);

[Mark Seaborn, 2012/09/18 03:24:34]

Nit: we generally don't use assert() in trusted code.  Use CHECK() or
NaClLog(LOG_FATAL,...) instead

[petarj, 2012/09/19 17:27:51]

Done.

+#endif
+    *reinterpret_cast<uint32_t *>(vaddr) = kNaClFullStop;
+  }
+};
+
+EXTERN_C_BEGIN
+
+int NCValidateSegment(uint8_t *mbase, uint32_t vbase, size_t size,
+                      bool stubout_mode) {
+  SfiValidator validator(
+      16,                            // 64,  // bytes per bundle
+      1U * NACL_DATA_SEGMENT_START,  // bytes of code space
+      1U * (1<<NACL_MAX_ADDR_BITS),  // bytes of data space // keep in sync w/
+                                     // SConstruct: irt_compatible_rodata_addr
+      kRegListReserved,              // read only register(s)
+      kRegisterStack);               // data addressing register(s)
+  bool success = false;
+
+  vector<CodeSegment> segments;
+  segments.push_back(CodeSegment(mbase, vbase, size));
+
+  if (stubout_mode) {
+    StuboutProblemSink sink;
+    success = validator.Validate(segments, &sink);
+  } else {
+    EarlyExitProblemSink sink;
+    success = validator.Validate(segments, &sink);
+  }
+  if (!success) return 2;
+
+  return 0;
+}
+
+static NaClValidationStatus ApplyValidatorMips(
+    uintptr_t guest_addr,
+    uint8_t *data,
+    size_t size,
+    int stubout_mode,
+    int readonly_text,
+    const NaClCPUFeaturesMips *cpu_features,
+    struct NaClValidationCache *cache) {
+  NaClValidationStatus status = NaClValidationFailedNotImplemented;
+  UNREFERENCED_PARAMETER(cpu_features);
+  UNREFERENCED_PARAMETER(cache);
+  if (stubout_mode) {
+    NCValidateSegment(data, guest_addr, size, true);
+    status = NaClValidationSucceeded;
+  } else if (readonly_text) {
+    status = NaClValidationFailedNotImplemented;
+  } else {
+    status = ((0 == NCValidateSegment(data, guest_addr, size, false))
+                  ? NaClValidationSucceeded : NaClValidationFailed);
+  }
+  return status;
+}
+
+static NaClValidationStatus ValidatorCodeReplacementNotImplemented(
+     uintptr_t guest_addr,
+     uint8_t *data_old,
+     uint8_t *data_new,
+     size_t size,
+     const NaClCPUFeatures *cpu_features) {
+  UNREFERENCED_PARAMETER(guest_addr);
+  UNREFERENCED_PARAMETER(data_old);
+  UNREFERENCED_PARAMETER(data_new);
+  UNREFERENCED_PARAMETER(size);
+  UNREFERENCED_PARAMETER(cpu_features);
+  return NaClValidationFailedNotImplemented;
+}
+
+static NaClValidationStatus ValidatorCopyNotImplemented(
+     uintptr_t guest_addr,
+     uint8_t *data_old,
+     uint8_t *data_new,
+     size_t size,
+     const NaClCPUFeatures *cpu_features,
+     NaClCopyInstructionFunc copy_func) {
+  UNREFERENCED_PARAMETER(guest_addr);
+  UNREFERENCED_PARAMETER(data_old);
+  UNREFERENCED_PARAMETER(data_new);
+  UNREFERENCED_PARAMETER(size);
+  UNREFERENCED_PARAMETER(cpu_features);
+  UNREFERENCED_PARAMETER(copy_func);
+  return NaClValidationFailedNotImplemented;
+}
+
+static struct NaClValidatorInterface validator = {
+  ApplyValidatorMips,
+  ValidatorCopyNotImplemented,
+  ValidatorCodeReplacementNotImplemented,
+};
+
+const struct NaClValidatorInterface *NaClValidatorCreateMips() {
+  return &validator;
+}
+
+/*
+ * When safe instruction copying gets implemented for MIPS, it should be moved to

[Mark Seaborn, 2012/09/18 03:24:34]

Nit: this line is >80 chars long, please re-wrap

[petarj, 2012/09/19 17:27:51]

Done.

+ * be part of sel_ldr, not the validator.
+ */
+int NaClCopyInstruction(uint8_t *dst, uint8_t *src, uint8_t sz) {
+  UNREFERENCED_PARAMETER(dst);
+  UNREFERENCED_PARAMETER(src);
+  UNREFERENCED_PARAMETER(sz);
+
+  return 0;
+}
+
+EXTERN_C_END