Warning, file /libraries/qca/src/botantools/botan/big_code.cpp was not indexed or was modified since last indexation (in which case cross-reference links may be missing, inaccurate or erroneous).

 /*
 Copyright (C) 1999-2007 The Botan Project. All rights reserved.
 
 Redistribution and use in source and binary forms, for any use, with or without
 modification, is permitted provided that the following conditions are met:
 
 1. Redistributions of source code must retain the above copyright notice, this
 list of conditions, and the following disclaimer.
 
 2. Redistributions in binary form must reproduce the above copyright notice,
 this list of conditions, and the following disclaimer in the documentation
 and/or other materials provided with the distribution.
 
 THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) "AS IS" AND ANY EXPRESS OR IMPLIED
 WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE DISCLAIMED.
 
 IN NO EVENT SHALL THE AUTHOR(S) OR CONTRIBUTOR(S) BE LIABLE FOR ANY DIRECT,
 INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 // LICENSEHEADER_END
 namespace QCA { // WRAPNS_LINE
 /*************************************************
  * BigInt Encoding/Decoding Source File           *
  * (C) 1999-2007 The Botan Project                *
  *************************************************/
 
 } // WRAPNS_LINE
 #include <botan/bigint.h>
 namespace QCA { // WRAPNS_LINE
 } // WRAPNS_LINE
 #include <botan/numthry.h>
 namespace QCA { // WRAPNS_LINE
 } // WRAPNS_LINE
 #include <botan/charset.h>
 namespace QCA { // WRAPNS_LINE
 #ifndef BOTAN_MINIMAL_BIGINT
 } // WRAPNS_LINE
 #include <botan/hex.h>
 namespace QCA { // WRAPNS_LINE
 #endif
 
 namespace Botan {
 
 /*************************************************
  * Encode a BigInt                                *
  *************************************************/
 void BigInt::encode(byte output[], const BigInt &n, Base base)
 {
     if (base == Binary)
         n.binary_encode(output);
 #ifndef BOTAN_MINIMAL_BIGINT
     else if (base == Hexadecimal) {
         SecureVector<byte> binary(n.encoded_size(Binary));
         n.binary_encode(binary);
         for (u32bit j = 0; j != binary.size(); ++j)
             Hex_Encoder::encode(binary[j], output + 2 * j);
     }
 #endif
     else if (base == Octal) {
         BigInt       copy        = n;
         const u32bit output_size = n.encoded_size(Octal);
         for (u32bit j = 0; j != output_size; ++j) {
             output[output_size - 1 - j] = Charset::digit2char(copy % 8);
             copy /= 8;
         }
     } else if (base == Decimal) {
         BigInt copy = n;
         BigInt remainder;
         copy.set_sign(Positive);
         const u32bit output_size = n.encoded_size(Decimal);
         for (u32bit j = 0; j != output_size; ++j) {
             divide(copy, 10, copy, remainder);
             output[output_size - 1 - j] = Charset::digit2char(remainder.word_at(0));
             if (copy.is_zero()) {
                 if (j < output_size - 1) {
                     int extra = output_size - 1 - j;
                     memmove(output, output + extra, output_size - extra);
                     memset(output + output_size - extra, 0, extra);
                 }
                 break;
             }
         }
     } else
         throw Invalid_Argument("Unknown BigInt encoding method");
 }
 
 /*************************************************
  * Encode a BigInt                                *
  *************************************************/
 SecureVector<byte> BigInt::encode(const BigInt &n, Base base)
 {
     SecureVector<byte> output(n.encoded_size(base));
     encode(output, n, base);
     if (base != Binary)
         for (u32bit j = 0; j != output.size(); ++j)
             if (output[j] == 0)
                 output[j] = '0';
     return output;
 }
 
 /*************************************************
  * Encode a BigInt, with leading 0s if needed     *
  *************************************************/
 SecureVector<byte> BigInt::encode_1363(const BigInt &n, u32bit bytes)
 {
     const u32bit n_bytes = n.bytes();
     if (n_bytes > bytes)
         throw Encoding_Error("encode_1363: n is too large to encode properly");
 
     const u32bit leading_0s = bytes - n_bytes;
 
     SecureVector<byte> output(bytes);
     encode(output + leading_0s, n, Binary);
     return output;
 }
 
 /*************************************************
  * Decode a BigInt                                *
  *************************************************/
 BigInt BigInt::decode(const MemoryRegion<byte> &buf, Base base)
 {
     return BigInt::decode(buf, buf.size(), base);
 }
 
 /*************************************************
  * Decode a BigInt                                *
  *************************************************/
 BigInt BigInt::decode(const byte buf[], u32bit length, Base base)
 {
     BigInt r;
     if (base == Binary)
         r.binary_decode(buf, length);
 #ifndef BOTAN_MINIMAL_BIGINT
     else if (base == Hexadecimal) {
         SecureVector<byte> hex;
         for (u32bit j = 0; j != length; ++j)
             if (Hex_Decoder::is_valid(buf[j]))
                 hex.append(buf[j]);
 
         u32bit             offset = (hex.size() % 2);
         SecureVector<byte> binary(hex.size() / 2 + offset);
 
         if (offset) {
             byte temp[2] = {'0', hex[0]};
             binary[0]    = Hex_Decoder::decode(temp);
         }
 
         for (u32bit j = offset; j != binary.size(); ++j)
             binary[j] = Hex_Decoder::decode(hex + 2 * j - offset);
         r.binary_decode(binary, binary.size());
     }
 #endif
     else if (base == Decimal || base == Octal) {
         const u32bit RADIX = ((base == Decimal) ? 10 : 8);
         for (u32bit j = 0; j != length; ++j) {
             byte x = Charset::char2digit(buf[j]);
             if (x >= RADIX) {
                 if (RADIX == 10)
                     throw Invalid_Argument("BigInt: Invalid decimal string");
                 else
                     throw Invalid_Argument("BigInt: Invalid octal string");
             }
 
             r *= RADIX;
             r += x;
         }
     } else
         throw Invalid_Argument("Unknown BigInt decoding method");
     return r;
 }
 
 }
 } // WRAPNS_LINE