Loading system/gd/packet/parser/Android.bp +1 −0 Original line number Diff line number Diff line Loading @@ -19,6 +19,7 @@ cc_binary_host { "enum_def.cc", "enum_gen.cc", "packet_def.cc", "parent_def.cc", "main.cc", "language_y.yy", "language_l.ll", Loading system/gd/packet/parser/packet_def.cc +9 −202 Original line number Diff line number Diff line Loading @@ -22,177 +22,11 @@ #include "fields/all_fields.h" #include "util.h" PacketDef::PacketDef(std::string name, FieldList fields) : name_(name), fields_(fields), parent_(nullptr){}; PacketDef::PacketDef(std::string name, FieldList fields, PacketDef* parent) : name_(name), fields_(fields), parent_(parent){}; PacketDef::PacketDef(std::string name, FieldList fields) : ParentDef(name, fields, nullptr){}; PacketDef::PacketDef(std::string name, FieldList fields, PacketDef* parent) : ParentDef(name, fields, parent){}; void PacketDef::AddParentConstraint(std::string field_name, std::variant<int64_t, std::string> value) { // NOTE: This could end up being very slow if there are a lot of constraints. const auto& parent_params = parent_->GetParamList(); const auto& constrained_field = parent_params.GetField(field_name); if (constrained_field == nullptr) { ERROR() << "Attempting to constrain field " << field_name << " in parent packet " << parent_->name_ << ", but no such field exists."; } if (constrained_field->GetFieldType() == PacketField::Type::SCALAR) { if (!std::holds_alternative<int64_t>(value)) { ERROR(constrained_field) << "Attemting to constrain a scalar field using an enum value in packet " << parent_->name_ << "."; } } else if (constrained_field->GetFieldType() == PacketField::Type::ENUM) { if (!std::holds_alternative<std::string>(value)) { ERROR(constrained_field) << "Attemting to constrain an enum field using an scalar value in packet " << parent_->name_ << "."; } const auto& enum_def = static_cast<EnumField*>(constrained_field)->GetEnumDef(); if (!enum_def.HasEntry(std::get<std::string>(value))) { ERROR(constrained_field) << "No matching enumeration \"" << std::get<std::string>(value) << "\" for constraint on enum in parent packet " << parent_->name_ << "."; } // For enums, we have to qualify the value using the enum type name. value = enum_def.GetTypeName() + "::" + std::get<std::string>(value); } else { ERROR(constrained_field) << "Field in parent packet " << parent_->name_ << " is not viable for constraining."; } parent_constraints_.insert(std::pair(field_name, value)); } // Assign all size fields to their corresponding variable length fields. // Will crash if // - there aren't any fields that don't match up to a field. // - the size field points to a fixed size field. // - if the size field comes after the variable length field. void PacketDef::AssignSizeFields() { for (const auto& field : fields_) { DEBUG() << "field name: " << field->GetName(); if (field->GetFieldType() != PacketField::Type::SIZE && field->GetFieldType() != PacketField::Type::COUNT) { continue; } const SizeField* size_field = nullptr; size_field = static_cast<SizeField*>(field); // Check to see if a corresponding field can be found. const auto& var_len_field = fields_.GetField(size_field->GetSizedFieldName()); if (var_len_field == nullptr) { ERROR(field) << "Could not find corresponding field for size/count field."; } // Do the ordering check to ensure the size field comes before the // variable length field. for (auto it = fields_.begin(); *it != size_field; it++) { DEBUG() << "field name: " << (*it)->GetName(); if (*it == var_len_field) { ERROR(var_len_field, size_field) << "Size/count field must come before the variable length field it describes."; } } if (var_len_field->GetFieldType() == PacketField::Type::PAYLOAD) { const auto& payload_field = static_cast<PayloadField*>(var_len_field); payload_field->SetSizeField(size_field); continue; } if (var_len_field->GetFieldType() == PacketField::Type::ARRAY) { const auto& array_field = static_cast<ArrayField*>(var_len_field); array_field->SetSizeField(size_field); continue; } // TODO: If there is an array field without a size field, check to see if the // parent has a size(payload) field. Or maybe we can just figure it out based // on the offsets fo the packet. // If we've reached this point then the field wasn't a variable length field. // Check to see if the field is a variable length field std::cerr << "Can not use size/count in reference to a fixed size field.\n"; abort(); } } void PacketDef::SetEndianness(bool is_little_endian) { is_little_endian_ = is_little_endian; } // Get the size for the packet. You scan specify without_payload in order // to exclude payload fields as child packets will be overriding it. Size PacketDef::GetSize(bool without_payload) const { auto size = Size(); for (const auto& field : fields_) { if (without_payload && field->GetFieldType() == PacketField::Type::PAYLOAD) { continue; } size += field->GetSize(); } if (parent_ != nullptr) { size += parent_->GetSize(true); } return size; } // Get the offset until the field is reached, if there is no field // returns an empty Size. from_end requests the offset to the field // starting from the end() iterator. If there is a field with an unknown // size along the traversal, then an empty size is returned. Size PacketDef::GetOffsetForField(std::string field_name, bool from_end) const { // Check first if the field exists. if (fields_.GetField(field_name) == nullptr) { if (field_name != "payload" && field_name != "body") { ERROR() << "Can't find a field offset for nonexistent field named: " << field_name; } else { return Size(); } } // We have to use a generic lambda to conditionally change iteration direction // due to iterator and reverse_iterator being different types. auto size_lambda = [&](auto from, auto to) -> Size { auto size = Size(0); for (auto it = from; it != to; it++) { // We've reached the field, end the loop. if ((*it)->GetName() == field_name) break; const auto& field = *it; // If there was a field that wasn't the payload with an unknown size, // return an empty Size. if (field->GetSize().empty()) { return Size(); } size += field->GetSize(); } return size; }; // Change iteration direction based on from_end. auto size = Size(); if (from_end) size = size_lambda(fields_.rbegin(), fields_.rend()); else size = size_lambda(fields_.begin(), fields_.end()); if (size.empty()) return Size(); // For parent packets we need the offset until a payload or body field. if (parent_ != nullptr) { auto parent_payload_offset = parent_->GetOffsetForField("payload", from_end); if (!parent_payload_offset.empty()) { size += parent_payload_offset; } else { parent_payload_offset = parent_->GetOffsetForField("body", from_end); if (!parent_payload_offset.empty()) { size += parent_payload_offset; } else { return Size(); } } } return size; PacketField* PacketDef::GetNewField(const std::string&, ParseLocation) const { return nullptr; // Packets can't be fields } void PacketDef::GenParserDefinition(std::ostream& s) const { Loading Loading @@ -410,6 +244,10 @@ void PacketDef::GenBuilderSize(std::ostream& s) const { s << "}\n"; } TypeDef::Type PacketDef::GetDefinitionType() const { return TypeDef::Type::PACKET; } void PacketDef::GenValidator(std::ostream& s) const { // Get the static offset for all of our fields. int bits_size = 0; Loading Loading @@ -589,32 +427,10 @@ void PacketDef::GenBuilderDefinition(std::ostream& s) const { GenBuilderParameterChecker(s); s << "\n"; GenBuilderMembers(s); GenMembers(s); s << "};\n"; } FieldList PacketDef::GetParamList() const { FieldList params; std::set<PacketField::Type> param_types = { PacketField::Type::SCALAR, PacketField::Type::ENUM, PacketField::Type::ARRAY, PacketField::Type::CUSTOM, PacketField::Type::BODY, PacketField::Type::PAYLOAD, }; if (parent_ != nullptr) { auto parent_params = parent_->GetParamList().GetFieldsWithTypes(param_types); // Do not include constrained fields in the params for (const auto& field : parent_params) { if (parent_constraints_.find(field->GetName()) == parent_constraints_.end()) { params.AppendField(field); } } } // Add the parameters for this packet. return params.Merge(fields_.GetFieldsWithTypes(param_types)); } FieldList PacketDef::GetParametersToValidate() const { FieldList params_to_validate; for (const auto& field : GetParamList()) { Loading Loading @@ -771,12 +587,3 @@ void PacketDef::GenBuilderConstructor(std::ostream& s) const { s << "}\n"; } void PacketDef::GenBuilderMembers(std::ostream& s) const { // Add the parameter list. for (int i = 0; i < fields_.size(); i++) { if (fields_[i]->GenBuilderParameter(s)) { s << "_;"; } } } system/gd/packet/parser/packet_def.h +5 −36 Original line number Diff line number Diff line Loading @@ -22,32 +22,14 @@ #include "enum_def.h" #include "field_list.h" #include "fields/packet_field.h" #include "parent_def.h" class PacketDef { class PacketDef : public ParentDef { public: PacketDef(std::string name, FieldList fields); PacketDef(std::string name, FieldList fields, PacketDef* parent); void AddParentConstraint(std::string field_name, std::variant<int64_t, std::string> value); // Assign all size fields to their corresponding variable length fields. // Will crash if // - there aren't any fields that don't match up to a field. // - the size field points to a fixed size field. // - if the size field comes after the variable length field. void AssignSizeFields(); void SetEndianness(bool is_little_endian); // Get the size for the packet. You scan specify without_payload in order // to exclude payload fields as child packets will be overriding it. Size GetSize(bool without_payload = false) const; // Get the offset until the field is reached, if there is no field // returns an empty Size. from_end requests the offset to the field // starting from the end() iterator. If there is a field with an unknown // size along the traversal, then an empty size is returned. Size GetOffsetForField(std::string field_name, bool from_end = false) const; PacketField* GetNewField(const std::string& name, ParseLocation loc) const; void GenParserDefinition(std::ostream& s) const; Loading @@ -59,9 +41,9 @@ class PacketDef { void GenValidator(std::ostream& s) const; void GenBuilderDefinition(std::ostream& s) const; TypeDef::Type GetDefinitionType() const; FieldList GetParamList() const; void GenBuilderDefinition(std::ostream& s) const; FieldList GetParametersToValidate() const; Loading @@ -70,17 +52,4 @@ class PacketDef { void GenBuilderParameterChecker(std::ostream& s) const; void GenBuilderConstructor(std::ostream& s) const; void GenBuilderMembers(std::ostream& s) const; std::string name_; FieldList fields_; std::variant<std::monostate, std::string, EnumDef*> specialize_on_; std::variant<std::monostate, int, std::string> specialization_value_; PacketDef* parent_; // Parent packet type std::map<std::string, std::variant<int64_t, std::string>> parent_constraints_; bool is_little_endian_; }; system/gd/packet/parser/parent_def.cc 0 → 100644 +243 −0 Original line number Diff line number Diff line /* * Copyright 2019 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "parent_def.h" #include "fields/all_fields.h" #include "util.h" ParentDef::ParentDef(std::string name, FieldList fields) : TypeDef(name), fields_(fields), parent_(nullptr){}; ParentDef::ParentDef(std::string name, FieldList fields, ParentDef* parent) : TypeDef(name), fields_(fields), parent_(parent){}; void ParentDef::AddParentConstraint(std::string field_name, std::variant<int64_t, std::string> value) { // NOTE: This could end up being very slow if there are a lot of constraints. const auto& parent_params = parent_->GetParamList(); const auto& constrained_field = parent_params.GetField(field_name); if (constrained_field == nullptr) { ERROR() << "Attempting to constrain field " << field_name << " in parent " << parent_->name_ << ", but no such field exists."; } if (constrained_field->GetFieldType() == PacketField::Type::SCALAR) { if (!std::holds_alternative<int64_t>(value)) { ERROR(constrained_field) << "Attemting to constrain a scalar field to an enum value in " << parent_->name_; } } else if (constrained_field->GetFieldType() == PacketField::Type::ENUM) { if (!std::holds_alternative<std::string>(value)) { ERROR(constrained_field) << "Attemting to constrain an enum field to a scalar value in " << parent_->name_; } const auto& enum_def = static_cast<EnumField*>(constrained_field)->GetEnumDef(); if (!enum_def.HasEntry(std::get<std::string>(value))) { ERROR(constrained_field) << "No matching enumeration \"" << std::get<std::string>(value) << "for constraint on enum in parent " << parent_->name_ << "."; } // For enums, we have to qualify the value using the enum type name. value = enum_def.GetTypeName() + "::" + std::get<std::string>(value); } else { ERROR(constrained_field) << "Field in parent " << parent_->name_ << " is not viable for constraining."; } parent_constraints_.insert(std::pair(field_name, value)); } // Assign all size fields to their corresponding variable length fields. // Will crash if // - there aren't any fields that don't match up to a field. // - the size field points to a fixed size field. // - if the size field comes after the variable length field. void ParentDef::AssignSizeFields() { for (const auto& field : fields_) { DEBUG() << "field name: " << field->GetName(); if (field->GetFieldType() != PacketField::Type::SIZE && field->GetFieldType() != PacketField::Type::COUNT) { continue; } const SizeField* size_field = static_cast<SizeField*>(field); // Check to see if a corresponding field can be found. const auto& var_len_field = fields_.GetField(size_field->GetSizedFieldName()); if (var_len_field == nullptr) { ERROR(field) << "Could not find corresponding field for size/count field."; } // Do the ordering check to ensure the size field comes before the // variable length field. for (auto it = fields_.begin(); *it != size_field; it++) { DEBUG() << "field name: " << (*it)->GetName(); if (*it == var_len_field) { ERROR(var_len_field, size_field) << "Size/count field must come before the variable length field it describes."; } } if (var_len_field->GetFieldType() == PacketField::Type::PAYLOAD) { const auto& payload_field = static_cast<PayloadField*>(var_len_field); payload_field->SetSizeField(size_field); continue; } if (var_len_field->GetFieldType() == PacketField::Type::ARRAY) { const auto& array_field = static_cast<ArrayField*>(var_len_field); array_field->SetSizeField(size_field); continue; } // If we've reached this point then the field wasn't a variable length field. // Check to see if the field is a variable length field std::cerr << "Can not use size/count in reference to a fixed size field.\n"; abort(); } } void ParentDef::SetEndianness(bool is_little_endian) { is_little_endian_ = is_little_endian; } // Get the size. You scan specify without_payload in order to exclude payload fields as children will be overriding it. Size ParentDef::GetSize(bool without_payload) const { auto size = Size(); for (const auto& field : fields_) { if (without_payload && (field->GetFieldType() == PacketField::Type::PAYLOAD || field->GetFieldType() == PacketField::Type::BODY)) { continue; } // The offset to the field must be passed in as an argument for dynamically sized custom fields. if (field->GetFieldType() == PacketField::Type::CUSTOM && field->GetSize().has_dynamic()) { std::stringstream custom_field_size; // Custom fields are special as their size field takes an argument. custom_field_size << field->GetSize().dynamic_string() << "(begin()"; // Check if we can determine offset from begin(), otherwise error because by this point, // the size of the custom field is unknown and can't be subtracted from end() to get the // offset. auto offset = GetOffsetForField(field->GetName(), false); if (offset.empty()) { ERROR(field) << "Custom Field offset can not be determined from begin()."; } if (offset.bits() % 8 != 0) { ERROR(field) << "Custom fields must be byte aligned."; } if (offset.has_bits()) custom_field_size << " + " << offset.bits() / 8; if (offset.has_dynamic()) custom_field_size << " + " << offset.dynamic_string(); custom_field_size << ")"; size += custom_field_size.str(); continue; } size += field->GetSize(); } if (parent_ != nullptr) { size += parent_->GetSize(true); } return size; } // Get the offset until the field is reached, if there is no field // returns an empty Size. from_end requests the offset to the field // starting from the end() iterator. If there is a field with an unknown // size along the traversal, then an empty size is returned. Size ParentDef::GetOffsetForField(std::string field_name, bool from_end) const { // Check first if the field exists. if (fields_.GetField(field_name) == nullptr) { if (field_name != "payload" && field_name != "body") { ERROR() << "Can't find a field offset for nonexistent field named: " << field_name; } else { return Size(); } } // We have to use a generic lambda to conditionally change iteration direction // due to iterator and reverse_iterator being different types. auto size_lambda = [&](auto from, auto to) -> Size { auto size = Size(0); for (auto it = from; it != to; it++) { // We've reached the field, end the loop. if ((*it)->GetName() == field_name) break; const auto& field = *it; // If there was a field that wasn't the payload with an unknown size, // return an empty Size. if (field->GetSize().empty()) { return Size(); } size += field->GetSize(); } return size; }; // Change iteration direction based on from_end. auto size = Size(); if (from_end) size = size_lambda(fields_.rbegin(), fields_.rend()); else size = size_lambda(fields_.begin(), fields_.end()); if (size.empty()) return Size(); // We need the offset until a payload or body field. if (parent_ != nullptr) { auto parent_payload_offset = parent_->GetOffsetForField("payload", from_end); if (!parent_payload_offset.empty()) { size += parent_payload_offset; } else { parent_payload_offset = parent_->GetOffsetForField("body", from_end); if (!parent_payload_offset.empty()) { size += parent_payload_offset; } else { return Size(); } } } return size; } FieldList ParentDef::GetParamList() const { FieldList params; std::set<PacketField::Type> param_types = { PacketField::Type::SCALAR, PacketField::Type::ENUM, PacketField::Type::ARRAY, PacketField::Type::CUSTOM, PacketField::Type::BODY, PacketField::Type::PAYLOAD, }; if (parent_ != nullptr) { auto parent_params = parent_->GetParamList().GetFieldsWithTypes(param_types); // Do not include constrained fields in the params for (const auto& field : parent_params) { if (parent_constraints_.find(field->GetName()) == parent_constraints_.end()) { params.AppendField(field); } } } // Add our parameters. return params.Merge(fields_.GetFieldsWithTypes(param_types)); } void ParentDef::GenMembers(std::ostream& s) const { // Add the parameter list. for (int i = 0; i < fields_.size(); i++) { if (fields_[i]->GenBuilderParameter(s)) { s << "_;"; } } } system/gd/packet/parser/parent_def.h 0 → 100644 +64 −0 Original line number Diff line number Diff line /* * Copyright 2019 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #pragma once #include <map> #include <variant> #include "enum_def.h" #include "field_list.h" #include "fields/all_fields.h" #include "fields/packet_field.h" #include "parse_location.h" #include "type_def.h" class ParentDef : public TypeDef { public: ParentDef(std::string name, FieldList fields); ParentDef(std::string name, FieldList fields, ParentDef* parent); void AddParentConstraint(std::string field_name, std::variant<int64_t, std::string> value); // Assign all size fields to their corresponding variable length fields. // Will crash if // - there aren't any fields that don't match up to a field. // - the size field points to a fixed size field. // - if the size field comes after the variable length field. void AssignSizeFields(); void SetEndianness(bool is_little_endian); // Get the size. You scan specify without_payload to exclude payload and body fields as children override them. Size GetSize(bool without_payload = false) const; // Get the offset until the field is reached, if there is no field // returns an empty Size. from_end requests the offset to the field // starting from the end() iterator. If there is a field with an unknown // size along the traversal, then an empty size is returned. Size GetOffsetForField(std::string field_name, bool from_end = false) const; FieldList GetParamList() const; void GenMembers(std::ostream& s) const; FieldList fields_; ParentDef* parent_{nullptr}; std::map<std::string, std::variant<int64_t, std::string>> parent_constraints_; bool is_little_endian_; }; Loading
system/gd/packet/parser/Android.bp +1 −0 Original line number Diff line number Diff line Loading @@ -19,6 +19,7 @@ cc_binary_host { "enum_def.cc", "enum_gen.cc", "packet_def.cc", "parent_def.cc", "main.cc", "language_y.yy", "language_l.ll", Loading
system/gd/packet/parser/packet_def.cc +9 −202 Original line number Diff line number Diff line Loading @@ -22,177 +22,11 @@ #include "fields/all_fields.h" #include "util.h" PacketDef::PacketDef(std::string name, FieldList fields) : name_(name), fields_(fields), parent_(nullptr){}; PacketDef::PacketDef(std::string name, FieldList fields, PacketDef* parent) : name_(name), fields_(fields), parent_(parent){}; PacketDef::PacketDef(std::string name, FieldList fields) : ParentDef(name, fields, nullptr){}; PacketDef::PacketDef(std::string name, FieldList fields, PacketDef* parent) : ParentDef(name, fields, parent){}; void PacketDef::AddParentConstraint(std::string field_name, std::variant<int64_t, std::string> value) { // NOTE: This could end up being very slow if there are a lot of constraints. const auto& parent_params = parent_->GetParamList(); const auto& constrained_field = parent_params.GetField(field_name); if (constrained_field == nullptr) { ERROR() << "Attempting to constrain field " << field_name << " in parent packet " << parent_->name_ << ", but no such field exists."; } if (constrained_field->GetFieldType() == PacketField::Type::SCALAR) { if (!std::holds_alternative<int64_t>(value)) { ERROR(constrained_field) << "Attemting to constrain a scalar field using an enum value in packet " << parent_->name_ << "."; } } else if (constrained_field->GetFieldType() == PacketField::Type::ENUM) { if (!std::holds_alternative<std::string>(value)) { ERROR(constrained_field) << "Attemting to constrain an enum field using an scalar value in packet " << parent_->name_ << "."; } const auto& enum_def = static_cast<EnumField*>(constrained_field)->GetEnumDef(); if (!enum_def.HasEntry(std::get<std::string>(value))) { ERROR(constrained_field) << "No matching enumeration \"" << std::get<std::string>(value) << "\" for constraint on enum in parent packet " << parent_->name_ << "."; } // For enums, we have to qualify the value using the enum type name. value = enum_def.GetTypeName() + "::" + std::get<std::string>(value); } else { ERROR(constrained_field) << "Field in parent packet " << parent_->name_ << " is not viable for constraining."; } parent_constraints_.insert(std::pair(field_name, value)); } // Assign all size fields to their corresponding variable length fields. // Will crash if // - there aren't any fields that don't match up to a field. // - the size field points to a fixed size field. // - if the size field comes after the variable length field. void PacketDef::AssignSizeFields() { for (const auto& field : fields_) { DEBUG() << "field name: " << field->GetName(); if (field->GetFieldType() != PacketField::Type::SIZE && field->GetFieldType() != PacketField::Type::COUNT) { continue; } const SizeField* size_field = nullptr; size_field = static_cast<SizeField*>(field); // Check to see if a corresponding field can be found. const auto& var_len_field = fields_.GetField(size_field->GetSizedFieldName()); if (var_len_field == nullptr) { ERROR(field) << "Could not find corresponding field for size/count field."; } // Do the ordering check to ensure the size field comes before the // variable length field. for (auto it = fields_.begin(); *it != size_field; it++) { DEBUG() << "field name: " << (*it)->GetName(); if (*it == var_len_field) { ERROR(var_len_field, size_field) << "Size/count field must come before the variable length field it describes."; } } if (var_len_field->GetFieldType() == PacketField::Type::PAYLOAD) { const auto& payload_field = static_cast<PayloadField*>(var_len_field); payload_field->SetSizeField(size_field); continue; } if (var_len_field->GetFieldType() == PacketField::Type::ARRAY) { const auto& array_field = static_cast<ArrayField*>(var_len_field); array_field->SetSizeField(size_field); continue; } // TODO: If there is an array field without a size field, check to see if the // parent has a size(payload) field. Or maybe we can just figure it out based // on the offsets fo the packet. // If we've reached this point then the field wasn't a variable length field. // Check to see if the field is a variable length field std::cerr << "Can not use size/count in reference to a fixed size field.\n"; abort(); } } void PacketDef::SetEndianness(bool is_little_endian) { is_little_endian_ = is_little_endian; } // Get the size for the packet. You scan specify without_payload in order // to exclude payload fields as child packets will be overriding it. Size PacketDef::GetSize(bool without_payload) const { auto size = Size(); for (const auto& field : fields_) { if (without_payload && field->GetFieldType() == PacketField::Type::PAYLOAD) { continue; } size += field->GetSize(); } if (parent_ != nullptr) { size += parent_->GetSize(true); } return size; } // Get the offset until the field is reached, if there is no field // returns an empty Size. from_end requests the offset to the field // starting from the end() iterator. If there is a field with an unknown // size along the traversal, then an empty size is returned. Size PacketDef::GetOffsetForField(std::string field_name, bool from_end) const { // Check first if the field exists. if (fields_.GetField(field_name) == nullptr) { if (field_name != "payload" && field_name != "body") { ERROR() << "Can't find a field offset for nonexistent field named: " << field_name; } else { return Size(); } } // We have to use a generic lambda to conditionally change iteration direction // due to iterator and reverse_iterator being different types. auto size_lambda = [&](auto from, auto to) -> Size { auto size = Size(0); for (auto it = from; it != to; it++) { // We've reached the field, end the loop. if ((*it)->GetName() == field_name) break; const auto& field = *it; // If there was a field that wasn't the payload with an unknown size, // return an empty Size. if (field->GetSize().empty()) { return Size(); } size += field->GetSize(); } return size; }; // Change iteration direction based on from_end. auto size = Size(); if (from_end) size = size_lambda(fields_.rbegin(), fields_.rend()); else size = size_lambda(fields_.begin(), fields_.end()); if (size.empty()) return Size(); // For parent packets we need the offset until a payload or body field. if (parent_ != nullptr) { auto parent_payload_offset = parent_->GetOffsetForField("payload", from_end); if (!parent_payload_offset.empty()) { size += parent_payload_offset; } else { parent_payload_offset = parent_->GetOffsetForField("body", from_end); if (!parent_payload_offset.empty()) { size += parent_payload_offset; } else { return Size(); } } } return size; PacketField* PacketDef::GetNewField(const std::string&, ParseLocation) const { return nullptr; // Packets can't be fields } void PacketDef::GenParserDefinition(std::ostream& s) const { Loading Loading @@ -410,6 +244,10 @@ void PacketDef::GenBuilderSize(std::ostream& s) const { s << "}\n"; } TypeDef::Type PacketDef::GetDefinitionType() const { return TypeDef::Type::PACKET; } void PacketDef::GenValidator(std::ostream& s) const { // Get the static offset for all of our fields. int bits_size = 0; Loading Loading @@ -589,32 +427,10 @@ void PacketDef::GenBuilderDefinition(std::ostream& s) const { GenBuilderParameterChecker(s); s << "\n"; GenBuilderMembers(s); GenMembers(s); s << "};\n"; } FieldList PacketDef::GetParamList() const { FieldList params; std::set<PacketField::Type> param_types = { PacketField::Type::SCALAR, PacketField::Type::ENUM, PacketField::Type::ARRAY, PacketField::Type::CUSTOM, PacketField::Type::BODY, PacketField::Type::PAYLOAD, }; if (parent_ != nullptr) { auto parent_params = parent_->GetParamList().GetFieldsWithTypes(param_types); // Do not include constrained fields in the params for (const auto& field : parent_params) { if (parent_constraints_.find(field->GetName()) == parent_constraints_.end()) { params.AppendField(field); } } } // Add the parameters for this packet. return params.Merge(fields_.GetFieldsWithTypes(param_types)); } FieldList PacketDef::GetParametersToValidate() const { FieldList params_to_validate; for (const auto& field : GetParamList()) { Loading Loading @@ -771,12 +587,3 @@ void PacketDef::GenBuilderConstructor(std::ostream& s) const { s << "}\n"; } void PacketDef::GenBuilderMembers(std::ostream& s) const { // Add the parameter list. for (int i = 0; i < fields_.size(); i++) { if (fields_[i]->GenBuilderParameter(s)) { s << "_;"; } } }
system/gd/packet/parser/packet_def.h +5 −36 Original line number Diff line number Diff line Loading @@ -22,32 +22,14 @@ #include "enum_def.h" #include "field_list.h" #include "fields/packet_field.h" #include "parent_def.h" class PacketDef { class PacketDef : public ParentDef { public: PacketDef(std::string name, FieldList fields); PacketDef(std::string name, FieldList fields, PacketDef* parent); void AddParentConstraint(std::string field_name, std::variant<int64_t, std::string> value); // Assign all size fields to their corresponding variable length fields. // Will crash if // - there aren't any fields that don't match up to a field. // - the size field points to a fixed size field. // - if the size field comes after the variable length field. void AssignSizeFields(); void SetEndianness(bool is_little_endian); // Get the size for the packet. You scan specify without_payload in order // to exclude payload fields as child packets will be overriding it. Size GetSize(bool without_payload = false) const; // Get the offset until the field is reached, if there is no field // returns an empty Size. from_end requests the offset to the field // starting from the end() iterator. If there is a field with an unknown // size along the traversal, then an empty size is returned. Size GetOffsetForField(std::string field_name, bool from_end = false) const; PacketField* GetNewField(const std::string& name, ParseLocation loc) const; void GenParserDefinition(std::ostream& s) const; Loading @@ -59,9 +41,9 @@ class PacketDef { void GenValidator(std::ostream& s) const; void GenBuilderDefinition(std::ostream& s) const; TypeDef::Type GetDefinitionType() const; FieldList GetParamList() const; void GenBuilderDefinition(std::ostream& s) const; FieldList GetParametersToValidate() const; Loading @@ -70,17 +52,4 @@ class PacketDef { void GenBuilderParameterChecker(std::ostream& s) const; void GenBuilderConstructor(std::ostream& s) const; void GenBuilderMembers(std::ostream& s) const; std::string name_; FieldList fields_; std::variant<std::monostate, std::string, EnumDef*> specialize_on_; std::variant<std::monostate, int, std::string> specialization_value_; PacketDef* parent_; // Parent packet type std::map<std::string, std::variant<int64_t, std::string>> parent_constraints_; bool is_little_endian_; };
system/gd/packet/parser/parent_def.cc 0 → 100644 +243 −0 Original line number Diff line number Diff line /* * Copyright 2019 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "parent_def.h" #include "fields/all_fields.h" #include "util.h" ParentDef::ParentDef(std::string name, FieldList fields) : TypeDef(name), fields_(fields), parent_(nullptr){}; ParentDef::ParentDef(std::string name, FieldList fields, ParentDef* parent) : TypeDef(name), fields_(fields), parent_(parent){}; void ParentDef::AddParentConstraint(std::string field_name, std::variant<int64_t, std::string> value) { // NOTE: This could end up being very slow if there are a lot of constraints. const auto& parent_params = parent_->GetParamList(); const auto& constrained_field = parent_params.GetField(field_name); if (constrained_field == nullptr) { ERROR() << "Attempting to constrain field " << field_name << " in parent " << parent_->name_ << ", but no such field exists."; } if (constrained_field->GetFieldType() == PacketField::Type::SCALAR) { if (!std::holds_alternative<int64_t>(value)) { ERROR(constrained_field) << "Attemting to constrain a scalar field to an enum value in " << parent_->name_; } } else if (constrained_field->GetFieldType() == PacketField::Type::ENUM) { if (!std::holds_alternative<std::string>(value)) { ERROR(constrained_field) << "Attemting to constrain an enum field to a scalar value in " << parent_->name_; } const auto& enum_def = static_cast<EnumField*>(constrained_field)->GetEnumDef(); if (!enum_def.HasEntry(std::get<std::string>(value))) { ERROR(constrained_field) << "No matching enumeration \"" << std::get<std::string>(value) << "for constraint on enum in parent " << parent_->name_ << "."; } // For enums, we have to qualify the value using the enum type name. value = enum_def.GetTypeName() + "::" + std::get<std::string>(value); } else { ERROR(constrained_field) << "Field in parent " << parent_->name_ << " is not viable for constraining."; } parent_constraints_.insert(std::pair(field_name, value)); } // Assign all size fields to their corresponding variable length fields. // Will crash if // - there aren't any fields that don't match up to a field. // - the size field points to a fixed size field. // - if the size field comes after the variable length field. void ParentDef::AssignSizeFields() { for (const auto& field : fields_) { DEBUG() << "field name: " << field->GetName(); if (field->GetFieldType() != PacketField::Type::SIZE && field->GetFieldType() != PacketField::Type::COUNT) { continue; } const SizeField* size_field = static_cast<SizeField*>(field); // Check to see if a corresponding field can be found. const auto& var_len_field = fields_.GetField(size_field->GetSizedFieldName()); if (var_len_field == nullptr) { ERROR(field) << "Could not find corresponding field for size/count field."; } // Do the ordering check to ensure the size field comes before the // variable length field. for (auto it = fields_.begin(); *it != size_field; it++) { DEBUG() << "field name: " << (*it)->GetName(); if (*it == var_len_field) { ERROR(var_len_field, size_field) << "Size/count field must come before the variable length field it describes."; } } if (var_len_field->GetFieldType() == PacketField::Type::PAYLOAD) { const auto& payload_field = static_cast<PayloadField*>(var_len_field); payload_field->SetSizeField(size_field); continue; } if (var_len_field->GetFieldType() == PacketField::Type::ARRAY) { const auto& array_field = static_cast<ArrayField*>(var_len_field); array_field->SetSizeField(size_field); continue; } // If we've reached this point then the field wasn't a variable length field. // Check to see if the field is a variable length field std::cerr << "Can not use size/count in reference to a fixed size field.\n"; abort(); } } void ParentDef::SetEndianness(bool is_little_endian) { is_little_endian_ = is_little_endian; } // Get the size. You scan specify without_payload in order to exclude payload fields as children will be overriding it. Size ParentDef::GetSize(bool without_payload) const { auto size = Size(); for (const auto& field : fields_) { if (without_payload && (field->GetFieldType() == PacketField::Type::PAYLOAD || field->GetFieldType() == PacketField::Type::BODY)) { continue; } // The offset to the field must be passed in as an argument for dynamically sized custom fields. if (field->GetFieldType() == PacketField::Type::CUSTOM && field->GetSize().has_dynamic()) { std::stringstream custom_field_size; // Custom fields are special as their size field takes an argument. custom_field_size << field->GetSize().dynamic_string() << "(begin()"; // Check if we can determine offset from begin(), otherwise error because by this point, // the size of the custom field is unknown and can't be subtracted from end() to get the // offset. auto offset = GetOffsetForField(field->GetName(), false); if (offset.empty()) { ERROR(field) << "Custom Field offset can not be determined from begin()."; } if (offset.bits() % 8 != 0) { ERROR(field) << "Custom fields must be byte aligned."; } if (offset.has_bits()) custom_field_size << " + " << offset.bits() / 8; if (offset.has_dynamic()) custom_field_size << " + " << offset.dynamic_string(); custom_field_size << ")"; size += custom_field_size.str(); continue; } size += field->GetSize(); } if (parent_ != nullptr) { size += parent_->GetSize(true); } return size; } // Get the offset until the field is reached, if there is no field // returns an empty Size. from_end requests the offset to the field // starting from the end() iterator. If there is a field with an unknown // size along the traversal, then an empty size is returned. Size ParentDef::GetOffsetForField(std::string field_name, bool from_end) const { // Check first if the field exists. if (fields_.GetField(field_name) == nullptr) { if (field_name != "payload" && field_name != "body") { ERROR() << "Can't find a field offset for nonexistent field named: " << field_name; } else { return Size(); } } // We have to use a generic lambda to conditionally change iteration direction // due to iterator and reverse_iterator being different types. auto size_lambda = [&](auto from, auto to) -> Size { auto size = Size(0); for (auto it = from; it != to; it++) { // We've reached the field, end the loop. if ((*it)->GetName() == field_name) break; const auto& field = *it; // If there was a field that wasn't the payload with an unknown size, // return an empty Size. if (field->GetSize().empty()) { return Size(); } size += field->GetSize(); } return size; }; // Change iteration direction based on from_end. auto size = Size(); if (from_end) size = size_lambda(fields_.rbegin(), fields_.rend()); else size = size_lambda(fields_.begin(), fields_.end()); if (size.empty()) return Size(); // We need the offset until a payload or body field. if (parent_ != nullptr) { auto parent_payload_offset = parent_->GetOffsetForField("payload", from_end); if (!parent_payload_offset.empty()) { size += parent_payload_offset; } else { parent_payload_offset = parent_->GetOffsetForField("body", from_end); if (!parent_payload_offset.empty()) { size += parent_payload_offset; } else { return Size(); } } } return size; } FieldList ParentDef::GetParamList() const { FieldList params; std::set<PacketField::Type> param_types = { PacketField::Type::SCALAR, PacketField::Type::ENUM, PacketField::Type::ARRAY, PacketField::Type::CUSTOM, PacketField::Type::BODY, PacketField::Type::PAYLOAD, }; if (parent_ != nullptr) { auto parent_params = parent_->GetParamList().GetFieldsWithTypes(param_types); // Do not include constrained fields in the params for (const auto& field : parent_params) { if (parent_constraints_.find(field->GetName()) == parent_constraints_.end()) { params.AppendField(field); } } } // Add our parameters. return params.Merge(fields_.GetFieldsWithTypes(param_types)); } void ParentDef::GenMembers(std::ostream& s) const { // Add the parameter list. for (int i = 0; i < fields_.size(); i++) { if (fields_[i]->GenBuilderParameter(s)) { s << "_;"; } } }
system/gd/packet/parser/parent_def.h 0 → 100644 +64 −0 Original line number Diff line number Diff line /* * Copyright 2019 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #pragma once #include <map> #include <variant> #include "enum_def.h" #include "field_list.h" #include "fields/all_fields.h" #include "fields/packet_field.h" #include "parse_location.h" #include "type_def.h" class ParentDef : public TypeDef { public: ParentDef(std::string name, FieldList fields); ParentDef(std::string name, FieldList fields, ParentDef* parent); void AddParentConstraint(std::string field_name, std::variant<int64_t, std::string> value); // Assign all size fields to their corresponding variable length fields. // Will crash if // - there aren't any fields that don't match up to a field. // - the size field points to a fixed size field. // - if the size field comes after the variable length field. void AssignSizeFields(); void SetEndianness(bool is_little_endian); // Get the size. You scan specify without_payload to exclude payload and body fields as children override them. Size GetSize(bool without_payload = false) const; // Get the offset until the field is reached, if there is no field // returns an empty Size. from_end requests the offset to the field // starting from the end() iterator. If there is a field with an unknown // size along the traversal, then an empty size is returned. Size GetOffsetForField(std::string field_name, bool from_end = false) const; FieldList GetParamList() const; void GenMembers(std::ostream& s) const; FieldList fields_; ParentDef* parent_{nullptr}; std::map<std::string, std::variant<int64_t, std::string>> parent_constraints_; bool is_little_endian_; };
