makehash.c

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#include "stralloc.h"
#include "byte.h"
#include "surf.h"
#include "uint_t.h"
#include "makehash.h"
#include "idx.h"
#include "errtxt.h"
#include "logmsg.h"
 
#define WHO "makehash"

 
typedef struct {
  uint32 seed[32];
  uint32 sum[8];
  uint32 out[8];
  uint32 in[12];
  int todo;
} surfpcs;
 
#define SURFPCS_LEN 32
 
static void die_nomem() { logmsg(WHO,111,FATAL,ERR_NOMEM); }
 
static void surfpcs_init(surfpcs *s,const uint32 k[32])
{
  int i;
  for (i = 0;i < 32;++i) s->seed[i] = k[i];
  for (i = 0;i < 8;++i) s->sum[i] = 0;
  for (i = 0;i < 12;++i) s->in[i] = 0;
  s->todo = 0;
}
 
static uint32 littleendian[8] = {
  50462976, 117835012, 185207048, 252579084,
  319951120, 387323156, 454695192, 522067228
} ;
#define end ((unsigned char *) littleendian)
 
#define data ((unsigned char *) s->in)
#define outdata ((unsigned char *) s->out)

 
static void surfpcs_addlc(surfpcs *s,const unsigned char *x,unsigned int n)
{
  unsigned char ch;
  int i;
  while (n--) {
    ch = *x++;
    if (ch == ' ' || ch == '\t') continue;
    if (ch >= 'A' && ch <= 'Z')
      data[end[s->todo++]] = ch - 'A' + 'a';
    else
      data[end[s->todo++]] = ch;
    if (s->todo == 32) {
      s->todo = 0;
      if (!++s->in[8])
        if (!++s->in[9])
          if (!++s->in[10])
            ++s->in[11];
      surf(s->out,s->in,s->seed);
 
      for (i = 0; i < 8; ++i)
        s->sum[i] += s->out[i];
    }
  }
}
 
static void surfpcs_out(surfpcs *s,unsigned char h[32])
{
  int i;
  surfpcs_addlc(s,".",1);
 
  while (s->todo) 
    surfpcs_addlc(s,"",1);
 
  for (i = 0; i < 8; ++i) s->in[i] = s->sum[i];
  for (; i < 12; ++i) s->in[i] = 0;
  surf(s->out,s->in,s->seed);
  for (i = 0; i < 32; ++i) h[i] = outdata[end[i]];
}

 
void makehash(const char *indata,unsigned int inlen,char *hash)
{
  unsigned char h[32];
  surfpcs s;
  uint32 seed[32];
  int i;
 
  for (i = 0; i < 32; ++i) seed[i] = 0;
  surfpcs_init(&s,seed);
  surfpcs_addlc(&s,indata,inlen);
  surfpcs_out(&s,h);
  for (i = 0; i < 20; ++i)
    hash[i] = 'a' + (h[i] & 15);
}
 
static stralloc dummy = {0};

 
void mkauthhash(const char *s,unsigned int len,char *h)
{
  unsigned int i,j,k,l;
  char ch;
 
  j = k = l = 0;
  i = byte_rchr(s,len,'@');
  if (i < len) {             /* if not then i=sa->len, j=k=l=0 */
    j = i;
    while (++j < len) {      /* if not found, then j=sa->len */
      ch = s[j];
      if (ch == '>' || ch == ' ' || ch == ';') break;
    }
    k = i;
    while (k > 0) {          /* k <= i */
      ch = s[--k];
      if (ch == '<' || ch == ' ' || ch == ';') break;
    }
    l = k;                   /* k <= l <= i; */
    while (l < i && s[l] != '-') 
      ++l;
    if (!stralloc_copyb(&dummy,s + k, l - k)) die_nomem();
    if (!stralloc_catb(&dummy,s + i, j - i)) die_nomem();
    makehash(dummy.s,dummy.len,h);
  } else                     /* use entire line if no '@' found */
    makehash(s,len,h);
}