apt-pkg/contrib/sha512.cc

   1 /*
   2  * Cryptographic API.                                                   {{{
   3  *
   4  * SHA-512, as specified in
   5  * http://csrc.nist.gov/cryptval/shs/sha256-384-512.pdf
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the Free
   9  * Software Foundation; either version 2 of the License, or (at your option)
  10  * any later version.
  11  *
  12  */                                                                     /*}}}*/
  13
  14 #ifdef __GNUG__
  15 #pragma implementation "apt-pkg/sha512.h"
  16 #endif
  17
  18 #include <apt-pkg/sha512.h>
  19 #include <apt-pkg/sha2.h>
  20 #include <apt-pkg/strutl.h>
  21
  22 SHA512Summation::SHA512Summation()                                      /*{{{*/
  23 {
  24    SHA512_Init(&ctx);
  25    Done = false;
  26 }
  27                                                                         /*}}}*/
  28 bool SHA512Summation::Add(const unsigned char *inbuf,unsigned long len) /*{{{*/
  29 {
  30    if (Done)
  31       return false;
  32    SHA512_Update(&ctx, inbuf, len);
  33    return true;
  34 }
  35                                                                         /*}}}*/
  36 SHA512SumValue SHA512Summation::Result()                                /*{{{*/
  37 {
  38    if (!Done) {
  39       SHA512_Final(Sum, &ctx);
  40       Done = true;
  41    }
  42
  43    SHA512SumValue res;
  44    res.Set(Sum);
  45    return res;
  46 }
  47                                                                         /*}}}*/
  48 // SHA512SumValue::SHA512SumValue - Constructs the sum from a string   /*{{{*/
  49 // ---------------------------------------------------------------------
  50 /* The string form of a SHA512 is a 64 character hex number */
  51 SHA512SumValue::SHA512SumValue(string Str)
  52 {
  53    memset(Sum,0,sizeof(Sum));
  54    Set(Str);
  55 }
  56                                                                        /*}}}*/
  57 // SHA512SumValue::SHA512SumValue - Default constructor                /*{{{*/
  58 // ---------------------------------------------------------------------
  59 /* Sets the value to 0 */
  60 SHA512SumValue::SHA512SumValue()
  61 {
  62    memset(Sum,0,sizeof(Sum));
  63 }
  64                                                                        /*}}}*/
  65 // SHA512SumValue::Set - Set the sum from a string                     /*{{{*/
  66 // ---------------------------------------------------------------------
  67 /* Converts the hex string into a set of chars */
  68 bool SHA512SumValue::Set(string Str)
  69 {
  70    return Hex2Num(Str,Sum,sizeof(Sum));
  71 }
  72                                                                        /*}}}*/
  73 // SHA512SumValue::Value - Convert the number into a string            /*{{{*/
  74 // ---------------------------------------------------------------------
  75 /* Converts the set of chars into a hex string in lower case */
  76 string SHA512SumValue::Value() const
  77 {
  78    char Conv[16] =
  79       { '0','1','2','3','4','5','6','7','8','9','a','b',
  80       'c','d','e','f'
  81    };
  82    char Result[129];
  83    Result[128] = 0;
  84
  85    // Convert each char into two letters
  86    int J = 0;
  87    int I = 0;
  88    for (; I != 128; J++,I += 2)
  89    {
  90       Result[I] = Conv[Sum[J] >> 4];
  91       Result[I + 1] = Conv[Sum[J] & 0xF];
  92    }
  93
  94    return string(Result);
  95 }
  96                                                                         /*}}}*/
  97 // SHA512SumValue::operator == - Comparator                            /*{{{*/
  98 // ---------------------------------------------------------------------
  99 /* Call memcmp on the buffer */
 100 bool SHA512SumValue::operator == (const SHA512SumValue & rhs) const
 101 {
 102    return memcmp(Sum,rhs.Sum,sizeof(Sum)) == 0;
 103 }
 104                                                                        /*}}}*/
 105 // SHA512Summation::AddFD - Add content of file into the checksum      /*{{{*/
 106 // ---------------------------------------------------------------------
 107 /* */
 108 bool SHA512Summation::AddFD(int Fd,unsigned long Size)
 109 {
 110    unsigned char Buf[64 * 64];
 111    int Res = 0;
 112    int ToEOF = (Size == 0);
 113    while (Size != 0 || ToEOF)
 114    {
 115       unsigned n = sizeof(Buf);
 116       if (!ToEOF) n = min(Size,(unsigned long)n);
 117       Res = read(Fd,Buf,n);
 118       if (Res < 0 || (!ToEOF && (unsigned) Res != n)) // error, or short read
 119          return false;
 120       if (ToEOF && Res == 0) // EOF
 121          break;
 122       Size -= Res;
 123       Add(Buf,Res);
 124    }
 125    return true;
 126 }
 127                                                                        /*}}}*/
 128