Digest-Hashcash/Hashcash.xs

#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

#include <time.h>
#include <stdlib.h>
#include <stdint.h>

/* NIST Secure Hash Algorithm */
/* heavily modified by Uwe Hollerbach <uh@alumni.caltech edu> */
/* from Peter C. Gutmann's implementation as found in */
/* Applied Cryptography by Bruce Schneier */
/* Further modifications to include the "UNRAVEL" stuff, below */

/* This code is in the public domain */

/* pcg: I was tempted to just rip this code off, after all, if you don't
 * demand anything I am inclined not to give anything. *Sigh* something
 * kept me from doing it, so here's the truth: I took this code from the
 * SHA1 perl module, since it looked reasonably well-crafted. I modified
 * it here and there, though.
 */

/*
 * we have lots of micro-optimizations here, this is just for toying
 * around...
 */

/* don't expect _too_ much from compilers for now. */
#if __GNUC__ > 2
#  define restrict __restrict__
#  define inline __inline__
#  ifdef __i386
#     define GCCX86ASM 1
#  endif
#elif __STDC_VERSION__ < 199900
#  define restrict
#  define inline
#endif

#if __GNUC__ < 2
#  define __attribute__(x)
#endif

#ifdef __i386
#  define a_regparm(n) __attribute__((__regparm__(n)))
#else
#  define a_regparm(n)
#endif

#define a_const __attribute__((__const__))

/* Useful defines & typedefs */

#if defined(U64TYPE) && (defined(USE_64_BIT_INT) || ((BYTEORDER != 0x1234) && (BYTEORDER != 0x4321)))
typedef U64TYPE ULONG;
#  if BYTEORDER == 0x1234
#    undef BYTEORDER
#    define BYTEORDER 0x12345678
#  elif BYTEORDER == 0x4321
#    undef BYTEORDER
#    define BYTEORDER 0x87654321   
#  endif
#else
typedef uint_fast32_t ULONG;     /* 32-or-more-bit quantity */
#endif

#if GCCX86ASM
#  define zprefix(n) ({ int _r; __asm__ ("bsrl %1, %0" : "=r" (_r) : "r" (n)); 31 - _r ; })
#elif __GNUC__ > 2 && __GNUC_MINOR__ > 3
#  define zprefix(n) (__extension__ ({ uint32_t n__ = (n); n ? __builtin_clz (n) : 32; }))
#else
static int a_const zprefix (ULONG n)
{
  static char zp[256] =
    {
      8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4,
      3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
      2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
      2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
      1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
      1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
      1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
      1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    };

  return
    n > 0xffffff ?      zp[n >> 24]
    : n > 0xffff ?  8 + zp[n >> 16]
    : n >   0xff ? 16 + zp[n >>  8]
    :              24 + zp[n];
}
#endif

#define SHA_BLOCKSIZE           64
#define SHA_DIGESTSIZE          20

typedef struct {
    ULONG digest[5];            /* message digest */
    ULONG count;                /* 32-bit bit count */
    int local;                  /* unprocessed amount in data */
    U8 data[SHA_BLOCKSIZE];     /* SHA data buffer */
} SHA_INFO;


/* SHA f()-functions */
#define f1(x,y,z)       ((x & y) | (~x & z))
#define f2(x,y,z)       (x ^ y ^ z)
#define f3(x,y,z)       ((x & y) | (x & z) | (y & z))
#define f4(x,y,z)       (x ^ y ^ z)

/* SHA constants */
#define CONST1          0x5a827999L
#define CONST2          0x6ed9eba1L
#define CONST3          0x8f1bbcdcL
#define CONST4          0xca62c1d6L

/* truncate to 32 bits -- should be a null op on 32-bit machines */
#define T32(x)  ((x) & 0xffffffffL)

/* 32-bit rotate */
#define R32(x,n)        T32(((x << n) | (x >> (32 - n))))

/* specific cases, for when the overall rotation is unraveled */
#define FA(n)   \
    T = T32(R32(A,5) + f##n(B,C,D) + E + *WP++ + CONST##n); B = R32(B,30)

#define FB(n)   \
    E = T32(R32(T,5) + f##n(A,B,C) + D + *WP++ + CONST##n); A = R32(A,30)

#define FC(n)   \
    D = T32(R32(E,5) + f##n(T,A,B) + C + *WP++ + CONST##n); T = R32(T,30)

#define FD(n)   \
    C = T32(R32(D,5) + f##n(E,T,A) + B + *WP++ + CONST##n); E = R32(E,30)

#define FE(n)   \
    B = T32(R32(C,5) + f##n(D,E,T) + A + *WP++ + CONST##n); D = R32(D,30)

#define FT(n)   \
    A = T32(R32(B,5) + f##n(C,D,E) + T + *WP++ + CONST##n); C = R32(C,30)

static void a_regparm(1) sha_transform(SHA_INFO *restrict sha_info)
{
    int i;
    U8 *restrict dp;
    ULONG T, A, B, C, D, E, W[80], *restrict WP;

    dp = sha_info->data;

#if BYTEORDER == 0x1234
    assert(sizeof(ULONG) == 4);
#  ifdef HAS_NTOHL
    for (i = 0; i < 16; ++i) {
        T = *((ULONG *) dp);
        dp += 4;
        W[i] = ntohl (T);
    }
#  else
    for (i = 0; i < 16; ++i) {
        T = *((ULONG *) dp);
        dp += 4;
        W[i] =  ((T << 24) & 0xff000000) | ((T <<  8) & 0x00ff0000) |
                ((T >>  8) & 0x0000ff00) | ((T >> 24) & 0x000000ff);
    }
#  endif
#elif BYTEORDER == 0x4321
    assert(sizeof(ULONG) == 4);
    for (i = 0; i < 16; ++i) {
        T = *((ULONG *) dp);
        dp += 4;
        W[i] = T32(T);
    }
#elif BYTEORDER == 0x12345678
    assert(sizeof(ULONG) == 8);
    for (i = 0; i < 16; i += 2) {
        T = *((ULONG *) dp);
        dp += 8;
        W[i] =  ((T << 24) & 0xff000000) | ((T <<  8) & 0x00ff0000) |
                ((T >>  8) & 0x0000ff00) | ((T >> 24) & 0x000000ff);
        T >>= 32;
        W[i+1] = ((T << 24) & 0xff000000) | ((T <<  8) & 0x00ff0000) |
                 ((T >>  8) & 0x0000ff00) | ((T >> 24) & 0x000000ff);
    }
#elif BYTEORDER == 0x87654321
    assert(sizeof(ULONG) == 8);
    for (i = 0; i < 16; i += 2) {
        T = *((ULONG *) dp);
        dp += 8;
        W[i] = T32(T >> 32);
        W[i+1] = T32(T);
    }
#else
#error Unknown byte order -- you need to add code here
#endif

    for (i = 16; i < 80; ++i)
      {
        T = W[i-3] ^ W[i-8] ^ W[i-14] ^ W[i-16];
        W[i] = R32(T,1);
      }

    A = sha_info->digest[0];
    B = sha_info->digest[1];
    C = sha_info->digest[2];
    D = sha_info->digest[3];
    E = sha_info->digest[4];

    WP = W;
    FA(1); FB(1); FC(1); FD(1); FE(1); FT(1); FA(1); FB(1); FC(1); FD(1);
    FE(1); FT(1); FA(1); FB(1); FC(1); FD(1); FE(1); FT(1); FA(1); FB(1);
    FC(2); FD(2); FE(2); FT(2); FA(2); FB(2); FC(2); FD(2); FE(2); FT(2);
    FA(2); FB(2); FC(2); FD(2); FE(2); FT(2); FA(2); FB(2); FC(2); FD(2);
    FE(3); FT(3); FA(3); FB(3); FC(3); FD(3); FE(3); FT(3); FA(3); FB(3);
    FC(3); FD(3); FE(3); FT(3); FA(3); FB(3); FC(3); FD(3); FE(3); FT(3);
    FA(4); FB(4); FC(4); FD(4); FE(4); FT(4); FA(4); FB(4); FC(4); FD(4);
    FE(4); FT(4); FA(4); FB(4); FC(4); FD(4); FE(4); FT(4); FA(4); FB(4);

    sha_info->digest[0] = T32(sha_info->digest[0] + E);
    sha_info->digest[1] = T32(sha_info->digest[1] + T);
    sha_info->digest[2] = T32(sha_info->digest[2] + A);
    sha_info->digest[3] = T32(sha_info->digest[3] + B);
    sha_info->digest[4] = T32(sha_info->digest[4] + C);
}

/* initialize the SHA digest */

static void sha_init(SHA_INFO *restrict sha_info)
{
    sha_info->digest[0] = 0x67452301L;
    sha_info->digest[1] = 0xefcdab89L;
    sha_info->digest[2] = 0x98badcfeL;
    sha_info->digest[3] = 0x10325476L;
    sha_info->digest[4] = 0xc3d2e1f0L;
    sha_info->count = 0L;
    sha_info->local = 0;
}

/* update the SHA digest */

static void sha_update(SHA_INFO *restrict sha_info, U8 *restrict buffer, int count)
{
    int i;

    sha_info->count += count;
    if (sha_info->local) {
        i = SHA_BLOCKSIZE - sha_info->local;
        if (i > count) {
            i = count;
        }
        memcpy(((U8 *) sha_info->data) + sha_info->local, buffer, i);
        count -= i;
        buffer += i;
        sha_info->local += i;
        if (sha_info->local == SHA_BLOCKSIZE) {
            sha_transform(sha_info);
        } else {
            return;
        }
    }
    while (count >= SHA_BLOCKSIZE) {
        memcpy(sha_info->data, buffer, SHA_BLOCKSIZE);
        buffer += SHA_BLOCKSIZE;
        count -= SHA_BLOCKSIZE;
        sha_transform(sha_info);
    }
    memcpy(sha_info->data, buffer, count);
    sha_info->local = count;
}

/* finish computing the SHA digest */
static int sha_final(SHA_INFO *sha_info)
{
  int count = sha_info->count;
  int local = sha_info->local;

  sha_info->data[local] = 0x80;

  if (sha_info->local >= SHA_BLOCKSIZE - 8) {
    memset(sha_info->data + local + 1, 0, SHA_BLOCKSIZE - 1 - local);
    sha_transform(sha_info);
    memset(sha_info->data, 0, SHA_BLOCKSIZE - 2);
  } else {
    memset(sha_info->data + local + 1, 0, SHA_BLOCKSIZE - 3 - local);
  }

  sha_info->data[62] = count >> 5;
  sha_info->data[63] = count << 3;

  sha_transform (sha_info);

  return sha_info->digest[0]
           ? zprefix (sha_info->digest[0])
           : zprefix (sha_info->digest[1]) + 32;
}

#define TRIALCHAR "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!#$%&()*+,-./;<=>?@[]{}^_|"

static char       nextenc[256];

static char rand_char ()
{
  return TRIALCHAR[rand () % sizeof (TRIALCHAR)];
}

typedef double (*NVTime)(void);

static double simple_nvtime (void)
{
  return time (0);
}

static NVTime get_nvtime (void)
{
  SV **svp = hv_fetch (PL_modglobal, "Time::NVtime", 12, 0);

  if (svp && SvIOK(*svp))
    return INT2PTR(NVTime, SvIV(*svp));
  else
    return simple_nvtime;

}

MODULE = Digest::Hashcash               PACKAGE = Digest::Hashcash

BOOT:
{
   int i;

   for (i = 0; i < sizeof (TRIALCHAR); i++)
     nextenc[TRIALCHAR[i]] = TRIALCHAR[(i + 1) % sizeof (TRIALCHAR)];
}

PROTOTYPES: ENABLE

# could be improved quite a bit in accuracy
NV
_estimate_rounds ()
        CODE:
{
        char data[40];
        NVTime nvtime = get_nvtime ();
        NV t1, t2, t;
        int count = 0;
        SHA_INFO ctx;

        t = nvtime ();
        do {
          t1 = nvtime ();
        } while (t == t1);

        t = t2 = nvtime ();
        do {
          volatile int i;
          sha_init (&ctx);
          sha_update (&ctx, data, sizeof (data));
          i = sha_final (&ctx);

          if (!(++count & 1023))
            t2 = nvtime ();

        } while (t == t2);

        RETVAL = (NV)count / (t2 - t1);
}
        OUTPUT:
        RETVAL

SV *
_gentoken (int size, IV timestamp, char *resource, char *trial = "", int extrarand = 0)
        CODE:
{
        SHA_INFO ctx1, ctx;
        char *token, *seq, *s;
        int toklen, i;
        time_t tstamp = timestamp ? timestamp : time (0);
        struct tm *tm = gmtime (&tstamp);

        New (0, token,
             1 + 1                    // version
             + 12 + 1                 // time field sans century
             + strlen (resource) + 1  // ressource
             + strlen (trial) + extrarand + 8 + 1 // trial
             + 1,
             char);

        if (!token)
          croak ("out of memory");

        if (size > 64)
          croak ("size must be <= 64 in this implementation\n");

        toklen = sprintf (token, "%d:%02d%02d%02d%02d%02d%02d:%s:%s",
                          0, tm->tm_year % 100, tm->tm_mon + 1, tm->tm_mday,
                          tm->tm_hour, tm->tm_min, tm->tm_sec,
                          resource, trial);

        if (toklen > 8000)
          croak ("token length must be <= 8000 in this implementation\n");

        i = toklen + extrarand;
        while (toklen < i)
          token[toklen++] = rand_char ();

        sha_init (&ctx1);
        sha_update (&ctx1, token, toklen);

        seq = token + toklen;
        i +=  8;
        while (toklen < i)
          token[toklen++] = rand_char ();

        for (;;)
          {
            ctx = ctx1; // this "optimization" can help a lot for longer resource strings
            sha_update (&ctx, seq, 8);
            i = sha_final (&ctx);

            if (i >= size)
              break;

            s = seq;
            do {
              *s = nextenc [*s];
            } while (*s++ == 'a');
          }

        RETVAL = newSVpvn (token, toklen);
}
        OUTPUT:
        RETVAL

int
_prefixlen (SV *tok)
        CODE:
{
        STRLEN toklen;
        char *token = SvPV (tok, toklen);
        SHA_INFO ctx;

        sha_init (&ctx);
        sha_update (&ctx, token, toklen);
        RETVAL = sha_final (&ctx);
}
        OUTPUT:
        RETVAL


Revision:	1.6
Committed:	Sun Jun 27 13:30:43 2004 UTC (19 years, 10 months ago) by root
Branch:	MAIN
Changes since 1.5:	+6 -6 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	#include "EXTERN.h"
2			#include "perl.h"
3			#include "XSUB.h"
4
5			#include <time.h>
6			#include <stdlib.h>
7			#include <stdint.h>
8
9			/* NIST Secure Hash Algorithm */
10			/* heavily modified by Uwe Hollerbach <uh@alumni.caltech edu> */
11			/* from Peter C. Gutmann's implementation as found in */
12			/* Applied Cryptography by Bruce Schneier */
13			/* Further modifications to include the "UNRAVEL" stuff, below */
14
15			/* This code is in the public domain */
16
17			/* pcg: I was tempted to just rip this code off, after all, if you don't
18			* demand anything I am inclined not to give anything. Sigh something
19			* kept me from doing it, so here's the truth: I took this code from the
20			* SHA1 perl module, since it looked reasonably well-crafted. I modified
21			* it here and there, though.
22			*/
23
24	root	1.5	/*
25			* we have lots of micro-optimizations here, this is just for toying
26			* around...
27			*/
28
29	root	1.1	/* don't expect _too_ much from compilers for now. */
30	root	1.2	#if __GNUC__ > 2
31	root	1.1	# define restrict __restrict__
32	root	1.2	# define inline __inline__
33			# ifdef __i386
34			# define GCCX86ASM 1
35			# endif
36	root	1.1	#elif __STDC_VERSION__ < 199900
37			# define restrict
38	root	1.2	# define inline
39	root	1.1	#endif
40
41	root	1.5	#if __GNUC__ < 2
42			# define __attribute__(x)
43			#endif
44
45			#ifdef __i386
46			# define a_regparm(n) __attribute__((__regparm__(n)))
47			#else
48			# define a_regparm(n)
49			#endif
50
51			#define a_const __attribute__((__const__))
52
53	root	1.1	/* Useful defines & typedefs */
54
55			#if defined(U64TYPE) && (defined(USE_64_BIT_INT) \|\| ((BYTEORDER != 0x1234) && (BYTEORDER != 0x4321)))
56			typedef U64TYPE ULONG;
57	root	1.4	# if BYTEORDER == 0x1234
58			# undef BYTEORDER
59			# define BYTEORDER 0x12345678
60			# elif BYTEORDER == 0x4321
61			# undef BYTEORDER
62			# define BYTEORDER 0x87654321
63			# endif
64	root	1.1	#else
65			typedef uint_fast32_t ULONG; /* 32-or-more-bit quantity */
66			#endif
67
68	root	1.2	#if GCCX86ASM
69			# define zprefix(n) ({ int _r; __asm__ ("bsrl %1, %0" : "=r" (_r) : "r" (n)); 31 - _r ; })
70	root	1.4	#elif __GNUC__ > 2 && __GNUC_MINOR__ > 3
71			# define zprefix(n) (__extension__ ({ uint32_t n__ = (n); n ? __builtin_clz (n) : 32; }))
72	root	1.2	#else
73	root	1.5	static int a_const zprefix (ULONG n)
74	root	1.2	{
75			static char zp[256] =
76			{
77			8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4,
78			3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
79			2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
80			2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
81			1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
82			1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
83			1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
84			1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
85			0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
86			0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
87			0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
88			0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
89			0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
90			0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
91			0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
92			0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
93			};
94
95			return
96			n > 0xffffff ? zp[n >> 24]
97			: n > 0xffff ? 8 + zp[n >> 16]
98			: n > 0xff ? 16 + zp[n >> 8]
99			: 24 + zp[n];
100			}
101			#endif
102
103	root	1.1	#define SHA_BLOCKSIZE 64
104			#define SHA_DIGESTSIZE 20
105
106			typedef struct {
107			ULONG digest[5]; /* message digest */
108			ULONG count; /* 32-bit bit count */
109	root	1.2	int local; /* unprocessed amount in data */
110	root	1.1	U8 data[SHA_BLOCKSIZE]; /* SHA data buffer */
111			} SHA_INFO;
112
113
114			/* SHA f()-functions */
115			#define f1(x,y,z) ((x & y) \| (~x & z))
116			#define f2(x,y,z) (x ^ y ^ z)
117			#define f3(x,y,z) ((x & y) \| (x & z) \| (y & z))
118			#define f4(x,y,z) (x ^ y ^ z)
119
120			/* SHA constants */
121			#define CONST1 0x5a827999L
122			#define CONST2 0x6ed9eba1L
123			#define CONST3 0x8f1bbcdcL
124			#define CONST4 0xca62c1d6L
125
126			/* truncate to 32 bits -- should be a null op on 32-bit machines */
127			#define T32(x) ((x) & 0xffffffffL)
128
129			/* 32-bit rotate */
130			#define R32(x,n) T32(((x << n) \| (x >> (32 - n))))
131
132			/* specific cases, for when the overall rotation is unraveled */
133			#define FA(n) \
134			T = T32(R32(A,5) + f##n(B,C,D) + E + *WP++ + CONST##n); B = R32(B,30)
135
136			#define FB(n) \
137			E = T32(R32(T,5) + f##n(A,B,C) + D + *WP++ + CONST##n); A = R32(A,30)
138
139			#define FC(n) \
140			D = T32(R32(E,5) + f##n(T,A,B) + C + *WP++ + CONST##n); T = R32(T,30)
141
142			#define FD(n) \
143			C = T32(R32(D,5) + f##n(E,T,A) + B + *WP++ + CONST##n); E = R32(E,30)
144
145			#define FE(n) \
146			B = T32(R32(C,5) + f##n(D,E,T) + A + *WP++ + CONST##n); D = R32(D,30)
147
148			#define FT(n) \
149			A = T32(R32(B,5) + f##n(C,D,E) + T + *WP++ + CONST##n); C = R32(C,30)
150
151	root	1.5	static void a_regparm(1) sha_transform(SHA_INFO *restrict sha_info)
152	root	1.1	{
153			int i;
154	root	1.5	U8 *restrict dp;
155	root	1.2	ULONG T, A, B, C, D, E, W[80], *restrict WP;
156	root	1.1
157			dp = sha_info->data;
158
159			#if BYTEORDER == 0x1234
160			assert(sizeof(ULONG) == 4);
161	root	1.2	# ifdef HAS_NTOHL
162			for (i = 0; i < 16; ++i) {
163			T = ((ULONG ) dp);
164			dp += 4;
165			W[i] = ntohl (T);
166			}
167			# else
168	root	1.1	for (i = 0; i < 16; ++i) {
169			T = ((ULONG ) dp);
170			dp += 4;
171			W[i] = ((T << 24) & 0xff000000) \| ((T << 8) & 0x00ff0000) \|
172			((T >> 8) & 0x0000ff00) \| ((T >> 24) & 0x000000ff);
173			}
174	root	1.2	# endif
175			#elif BYTEORDER == 0x4321
176	root	1.1	assert(sizeof(ULONG) == 4);
177			for (i = 0; i < 16; ++i) {
178			T = ((ULONG ) dp);
179			dp += 4;
180			W[i] = T32(T);
181			}
182	root	1.2	#elif BYTEORDER == 0x12345678
183	root	1.1	assert(sizeof(ULONG) == 8);
184			for (i = 0; i < 16; i += 2) {
185			T = ((ULONG ) dp);
186			dp += 8;
187			W[i] = ((T << 24) & 0xff000000) \| ((T << 8) & 0x00ff0000) \|
188			((T >> 8) & 0x0000ff00) \| ((T >> 24) & 0x000000ff);
189			T >>= 32;
190			W[i+1] = ((T << 24) & 0xff000000) \| ((T << 8) & 0x00ff0000) \|
191			((T >> 8) & 0x0000ff00) \| ((T >> 24) & 0x000000ff);
192			}
193	root	1.2	#elif BYTEORDER == 0x87654321
194	root	1.1	assert(sizeof(ULONG) == 8);
195			for (i = 0; i < 16; i += 2) {
196			T = ((ULONG ) dp);
197			dp += 8;
198			W[i] = T32(T >> 32);
199			W[i+1] = T32(T);
200			}
201	root	1.2	#else
202			#error Unknown byte order -- you need to add code here
203	root	1.1	#endif
204
205	root	1.2	for (i = 16; i < 80; ++i)
206			{
207			T = W[i-3] ^ W[i-8] ^ W[i-14] ^ W[i-16];
208			W[i] = R32(T,1);
209			}
210	root	1.1
211			A = sha_info->digest[0];
212			B = sha_info->digest[1];
213			C = sha_info->digest[2];
214			D = sha_info->digest[3];
215			E = sha_info->digest[4];
216	root	1.2
217	root	1.1	WP = W;
218			FA(1); FB(1); FC(1); FD(1); FE(1); FT(1); FA(1); FB(1); FC(1); FD(1);
219			FE(1); FT(1); FA(1); FB(1); FC(1); FD(1); FE(1); FT(1); FA(1); FB(1);
220			FC(2); FD(2); FE(2); FT(2); FA(2); FB(2); FC(2); FD(2); FE(2); FT(2);
221			FA(2); FB(2); FC(2); FD(2); FE(2); FT(2); FA(2); FB(2); FC(2); FD(2);
222			FE(3); FT(3); FA(3); FB(3); FC(3); FD(3); FE(3); FT(3); FA(3); FB(3);
223			FC(3); FD(3); FE(3); FT(3); FA(3); FB(3); FC(3); FD(3); FE(3); FT(3);
224			FA(4); FB(4); FC(4); FD(4); FE(4); FT(4); FA(4); FB(4); FC(4); FD(4);
225			FE(4); FT(4); FA(4); FB(4); FC(4); FD(4); FE(4); FT(4); FA(4); FB(4);
226	root	1.2
227	root	1.1	sha_info->digest[0] = T32(sha_info->digest[0] + E);
228			sha_info->digest[1] = T32(sha_info->digest[1] + T);
229			sha_info->digest[2] = T32(sha_info->digest[2] + A);
230			sha_info->digest[3] = T32(sha_info->digest[3] + B);
231			sha_info->digest[4] = T32(sha_info->digest[4] + C);
232			}
233
234			/* initialize the SHA digest */
235
236	root	1.2	static void sha_init(SHA_INFO *restrict sha_info)
237	root	1.1	{
238			sha_info->digest[0] = 0x67452301L;
239			sha_info->digest[1] = 0xefcdab89L;
240			sha_info->digest[2] = 0x98badcfeL;
241			sha_info->digest[3] = 0x10325476L;
242			sha_info->digest[4] = 0xc3d2e1f0L;
243			sha_info->count = 0L;
244			sha_info->local = 0;
245			}
246
247			/* update the SHA digest */
248
249	root	1.2	static void sha_update(SHA_INFO restrict sha_info, U8 restrict buffer, int count)
250	root	1.1	{
251			int i;
252
253	root	1.2	sha_info->count += count;
254	root	1.1	if (sha_info->local) {
255			i = SHA_BLOCKSIZE - sha_info->local;
256			if (i > count) {
257			i = count;
258			}
259			memcpy(((U8 *) sha_info->data) + sha_info->local, buffer, i);
260			count -= i;
261			buffer += i;
262			sha_info->local += i;
263			if (sha_info->local == SHA_BLOCKSIZE) {
264			sha_transform(sha_info);
265			} else {
266			return;
267			}
268			}
269			while (count >= SHA_BLOCKSIZE) {
270			memcpy(sha_info->data, buffer, SHA_BLOCKSIZE);
271			buffer += SHA_BLOCKSIZE;
272			count -= SHA_BLOCKSIZE;
273			sha_transform(sha_info);
274			}
275			memcpy(sha_info->data, buffer, count);
276			sha_info->local = count;
277			}
278
279			/* finish computing the SHA digest */
280	root	1.2	static int sha_final(SHA_INFO *sha_info)
281	root	1.1	{
282	root	1.2	int count = sha_info->count;
283			int local = sha_info->local;
284	root	1.1
285	root	1.2	sha_info->data[local] = 0x80;
286	root	1.1
287	root	1.2	if (sha_info->local >= SHA_BLOCKSIZE - 8) {
288			memset(sha_info->data + local + 1, 0, SHA_BLOCKSIZE - 1 - local);
289			sha_transform(sha_info);
290			memset(sha_info->data, 0, SHA_BLOCKSIZE - 2);
291			} else {
292			memset(sha_info->data + local + 1, 0, SHA_BLOCKSIZE - 3 - local);
293			}
294
295			sha_info->data[62] = count >> 5;
296			sha_info->data[63] = count << 3;
297
298			sha_transform (sha_info);
299
300			return sha_info->digest[0]
301			? zprefix (sha_info->digest[0])
302			: zprefix (sha_info->digest[1]) + 32;
303	root	1.1	}
304
305			#define TRIALCHAR "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!#$%&()*+,-./;<=>?@[]{}^_\|"
306
307			static char nextenc[256];
308
309			static char rand_char ()
310			{
311			return TRIALCHAR[rand () % sizeof (TRIALCHAR)];
312			}
313
314	root	1.2	typedef double (*NVTime)(void);
315
316			static double simple_nvtime (void)
317			{
318			return time (0);
319			}
320
321			static NVTime get_nvtime (void)
322	root	1.1	{
323	root	1.2	SV **svp = hv_fetch (PL_modglobal, "Time::NVtime", 12, 0);
324
325			if (svp && SvIOK(*svp))
326			return INT2PTR(NVTime, SvIV(*svp));
327			else
328			return simple_nvtime;
329	root	1.1
330			}
331
332			MODULE = Digest::Hashcash PACKAGE = Digest::Hashcash
333
334			BOOT:
335			{
336			int i;
337
338			for (i = 0; i < sizeof (TRIALCHAR); i++)
339			nextenc[TRIALCHAR[i]] = TRIALCHAR[(i + 1) % sizeof (TRIALCHAR)];
340			}
341
342			PROTOTYPES: ENABLE
343
344	root	1.2	# could be improved quite a bit in accuracy
345			NV
346			_estimate_rounds ()
347	root	1.1	CODE:
348	root	1.3	{
349	root	1.2	char data[40];
350			NVTime nvtime = get_nvtime ();
351			NV t1, t2, t;
352			int count = 0;
353			SHA_INFO ctx;
354
355			t = nvtime ();
356			do {
357			t1 = nvtime ();
358			} while (t == t1);
359
360			t = t2 = nvtime ();
361			do {
362			volatile int i;
363			sha_init (&ctx);
364			sha_update (&ctx, data, sizeof (data));
365			i = sha_final (&ctx);
366
367			if (!(++count & 1023))
368			t2 = nvtime ();
369
370			} while (t == t2);
371
372			RETVAL = (NV)count / (t2 - t1);
373	root	1.3	}
374	root	1.1	OUTPUT:
375			RETVAL
376
377			SV *
378	root	1.2	_gentoken (int size, IV timestamp, char resource, char trial = "", int extrarand = 0)
379	root	1.1	CODE:
380	root	1.3	{
381	root	1.1	SHA_INFO ctx1, ctx;
382			char token, seq, *s;
383			int toklen, i;
384			time_t tstamp = timestamp ? timestamp : time (0);
385			struct tm *tm = gmtime (&tstamp);
386
387			New (0, token,
388	root	1.6	1 + 1 // version
389			+ 12 + 1 // time field sans century
390			+ strlen (resource) + 1 // ressource
391			+ strlen (trial) + extrarand + 8 + 1 // trial
392			+ 1,
393			char);
394	root	1.1
395			if (!token)
396			croak ("out of memory");
397
398	root	1.2	if (size > 64)
399			croak ("size must be <= 64 in this implementation\n");
400	root	1.1
401			toklen = sprintf (token, "%d:%02d%02d%02d%02d%02d%02d:%s:%s",
402			0, tm->tm_year % 100, tm->tm_mon + 1, tm->tm_mday,
403			tm->tm_hour, tm->tm_min, tm->tm_sec,
404			resource, trial);
405
406	root	1.2	if (toklen > 8000)
407			croak ("token length must be <= 8000 in this implementation\n");
408
409	root	1.1	i = toklen + extrarand;
410			while (toklen < i)
411			token[toklen++] = rand_char ();
412
413			sha_init (&ctx1);
414			sha_update (&ctx1, token, toklen);
415
416			seq = token + toklen;
417			i += 8;
418			while (toklen < i)
419			token[toklen++] = rand_char ();
420
421			for (;;)
422			{
423			ctx = ctx1; // this "optimization" can help a lot for longer resource strings
424			sha_update (&ctx, seq, 8);
425	root	1.2	i = sha_final (&ctx);
426	root	1.1
427	root	1.2	if (i >= size)
428	root	1.1	break;
429
430			s = seq;
431			do {
432			s = nextenc [s];
433			} while (*s++ == 'a');
434			}
435
436			RETVAL = newSVpvn (token, toklen);
437	root	1.3	}
438	root	1.1	OUTPUT:
439			RETVAL
440
441			int
442			_prefixlen (SV *tok)
443			CODE:
444	root	1.3	{
445	root	1.1	STRLEN toklen;
446			char *token = SvPV (tok, toklen);
447			SHA_INFO ctx;
448
449			sha_init (&ctx);
450			sha_update (&ctx, token, toklen);
451	root	1.2	RETVAL = sha_final (&ctx);
452	root	1.3	}
453	root	1.1	OUTPUT:
454			RETVAL
455
456