/* * BER Decoder * (C) 1999-2010 Jack Lloyd * * Distributed under the terms of the Botan license */ #ifndef BOTAN_BER_DECODER_H__ #define BOTAN_BER_DECODER_H__ #include #include namespace Botan { /** * BER Decoding Object */ class BOTAN_DLL BER_Decoder { public: BER_Object get_next_object(); void push_back(const BER_Object&); bool more_items() const; BER_Decoder& verify_end(); BER_Decoder& discard_remaining(); BER_Decoder start_cons(ASN1_Tag, ASN1_Tag = UNIVERSAL); BER_Decoder& end_cons(); BER_Decoder& raw_bytes(MemoryRegion&); BER_Decoder& decode_null(); BER_Decoder& decode(bool&); BER_Decoder& decode(u32bit&); BER_Decoder& decode(class BigInt&); BER_Decoder& decode(MemoryRegion&, ASN1_Tag); BER_Decoder& decode(bool&, ASN1_Tag, ASN1_Tag = CONTEXT_SPECIFIC); BER_Decoder& decode(u32bit&, ASN1_Tag, ASN1_Tag = CONTEXT_SPECIFIC); BER_Decoder& decode(class BigInt&, ASN1_Tag, ASN1_Tag = CONTEXT_SPECIFIC); BER_Decoder& decode(MemoryRegion&, ASN1_Tag, ASN1_Tag, ASN1_Tag = CONTEXT_SPECIFIC); BER_Decoder& decode(class ASN1_Object&); BER_Decoder& decode_octet_string_bigint(class BigInt&); template BER_Decoder& decode_optional(T& out, ASN1_Tag type_tag, ASN1_Tag class_tag, const T& default_value = T()); template BER_Decoder& decode_list(std::vector& out, bool clear_out = true); template BER_Decoder& decode_and_check(const T& expected, const std::string& error_msg) { T actual; decode(actual); if(actual != expected) throw Decoding_Error(error_msg); return (*this); } BER_Decoder& decode_optional_string(MemoryRegion&, ASN1_Tag, u16bit); BER_Decoder(DataSource&); BER_Decoder(const byte[], u32bit); BER_Decoder(const MemoryRegion&); BER_Decoder(const BER_Decoder&); ~BER_Decoder(); private: BER_Decoder& operator=(const BER_Decoder&) { return (*this); } BER_Decoder* parent; DataSource* source; BER_Object pushed; mutable bool owns; }; /* * Decode an OPTIONAL or DEFAULT element */ template BER_Decoder& BER_Decoder::decode_optional(T& out, ASN1_Tag type_tag, ASN1_Tag class_tag, const T& default_value) { BER_Object obj = get_next_object(); if(obj.type_tag == type_tag && obj.class_tag == class_tag) { if(class_tag & CONSTRUCTED) BER_Decoder(obj.value).decode(out).verify_end(); else { push_back(obj); decode(out, type_tag, class_tag); } } else { out = default_value; push_back(obj); } return (*this); } /* * Decode a list of homogenously typed values */ template BER_Decoder& BER_Decoder::decode_list(std::vector& vec, bool clear_it) { if(clear_it) vec.clear(); while(more_items()) { T value; decode(value); vec.push_back(value); } return (*this); } } #endif