/************************************************* * OpenPGP Source File * * (C) 1999-2007 Jack Lloyd * *************************************************/ #include <botan/openpgp.h> #include <botan/filters.h> #include <botan/charset.h> namespace Botan { namespace OpenPGP { /************************************************* * OpenPGP Base64 encoding * *************************************************/ std::string encode(const byte input[], u32bit length, const std::string& label, const std::map<std::string, std::string>& headers) { const std::string PGP_HEADER = "-----BEGIN PGP " + label + "-----\n"; const std::string PGP_TRAILER = "-----END PGP " + label + "-----\n"; const u32bit PGP_WIDTH = 64; std::string pgp_encoded = PGP_HEADER; if(headers.find("Version") != headers.end()) pgp_encoded += "Version: " + headers.find("Version")->second + '\n'; std::map<std::string, std::string>::const_iterator i = headers.begin(); while(i != headers.end()) { if(i->first != "Version") pgp_encoded += i->first + ": " + i->second + '\n'; ++i; } pgp_encoded += '\n'; Pipe pipe(new Fork( new Base64_Encoder(true, PGP_WIDTH), new Chain(new Hash_Filter("CRC24"), new Base64_Encoder) ) ); pipe.process_msg(input, length); pgp_encoded += pipe.read_all_as_string(0); pgp_encoded += '=' + pipe.read_all_as_string(1) + '\n'; pgp_encoded += PGP_TRAILER; return pgp_encoded; } /************************************************* * OpenPGP Base64 encoding * *************************************************/ std::string encode(const byte input[], u32bit length, const std::string& type) { std::map<std::string, std::string> empty; return encode(input, length, type, empty); } /************************************************* * OpenPGP Base64 decoding * *************************************************/ SecureVector<byte> decode(DataSource& source, std::string& label, std::map<std::string, std::string>& headers) { const u32bit RANDOM_CHAR_LIMIT = 5; const std::string PGP_HEADER1 = "-----BEGIN PGP "; const std::string PGP_HEADER2 = "-----"; u32bit position = 0; while(position != PGP_HEADER1.length()) { byte b; if(!source.read_byte(b)) throw Decoding_Error("PGP: No PGP header found"); if(b == PGP_HEADER1[position]) ++position; else if(position >= RANDOM_CHAR_LIMIT) throw Decoding_Error("PGP: Malformed PGP header"); else position = 0; } position = 0; while(position != PGP_HEADER2.length()) { byte b; if(!source.read_byte(b)) throw Decoding_Error("PGP: No PGP header found"); if(b == PGP_HEADER2[position]) ++position; else if(position) throw Decoding_Error("PGP: Malformed PGP header"); if(position == 0) label += static_cast<char>(b); } headers.clear(); bool end_of_headers = false; while(!end_of_headers) { std::string this_header; byte b = 0; while(b != '\n') { if(!source.read_byte(b)) throw Decoding_Error("PGP: Bad armor header"); if(b != '\n') this_header += static_cast<char>(b); } end_of_headers = true; for(u32bit j = 0; j != this_header.length(); ++j) if(!Charset::is_space(this_header[j])) end_of_headers = false; if(!end_of_headers) { std::string::size_type pos = this_header.find(": "); if(pos == std::string::npos) throw Decoding_Error("OpenPGP: Bad headers"); std::string key = this_header.substr(0, pos); std::string value = this_header.substr(pos + 2, std::string::npos); headers[key] = value; } } Pipe base64(new Base64_Decoder, new Fork(0, new Chain(new Hash_Filter("CRC24"), new Base64_Encoder) ) ); base64.start_msg(); const std::string PGP_TRAILER = "-----END PGP " + label + "-----"; position = 0; bool newline_seen = 0; std::string crc; while(position != PGP_TRAILER.length()) { byte b; if(!source.read_byte(b)) throw Decoding_Error("PGP: No PGP trailer found"); if(b == PGP_TRAILER[position]) ++position; else if(position) throw Decoding_Error("PGP: Malformed PGP trailer"); if(b == '=' && newline_seen) { while(b != '\n') { if(!source.read_byte(b)) throw Decoding_Error("PGP: Bad CRC tail"); if(b != '\n') crc += static_cast<char>(b); } } else if(b == '\n') newline_seen = true; else if(position == 0) { base64.write(b); newline_seen = false; } } base64.end_msg(); if(crc != "" && crc != base64.read_all_as_string(1)) throw Decoding_Error("PGP: Corrupt CRC"); return base64.read_all(); } /************************************************* * OpenPGP Base64 decoding * *************************************************/ SecureVector<byte> decode(DataSource& source, std::string& label) { std::map<std::string, std::string> ignored; return decode(source, label, ignored); } } }