mdw@git.distorted.org.uk Git - ezmlm/blob - makehash.c

   1 /*Id:$*/
   2 /*Name:$*/
   3
   4 #include "stralloc.h"
   5 #include "surf.h"
   6 #include "uint32.h"
   7 #include "makehash.h"
   8
   9 typedef struct {
  10   uint32 seed[32];
  11   uint32 sum[8];
  12   uint32 out[8];
  13   uint32 in[12];
  14   int todo;
  15 } surfpcs;
  16
  17 #define SURFPCS_LEN 32
  18
  19 static void surfpcs_init(s,k)
  20 surfpcs *s;
  21 uint32 k[32];
  22 {
  23   int i;
  24   for (i = 0;i < 32;++i) s->seed[i] = k[i];
  25   for (i = 0;i < 8;++i) s->sum[i] = 0;
  26   for (i = 0;i < 12;++i) s->in[i] = 0;
  27   s->todo = 0;
  28 }
  29
  30 static uint32 littleendian[8] = {
  31   50462976, 117835012, 185207048, 252579084,
  32   319951120, 387323156, 454695192, 522067228
  33 } ;
  34 #define end ((unsigned char *) littleendian)
  35
  36 #define data ((unsigned char *) s->in)
  37 #define outdata ((unsigned char *) s->out)
  38
  39 static void surfpcs_addlc(s,x,n)
  40         /* modified from Dan's surfpcs_add by skipping ' ' & '\t' and */
  41         /* case-independence */
  42 surfpcs *s;
  43 unsigned char *x;
  44 unsigned int n;
  45 {
  46   register unsigned char ch;
  47   int i;
  48   while (n--) {
  49     ch = *x++;
  50     if (ch == ' ' || ch == '\t') continue;
  51     if (ch >= 'A' && ch <= 'Z')
  52       data[end[s->todo++]] = ch - 'A' + 'a';
  53     else
  54       data[end[s->todo++]] = ch;
  55     if (s->todo == 32) {
  56       s->todo = 0;
  57       if (!++s->in[8])
  58         if (!++s->in[9])
  59           if (!++s->in[10])
  60             ++s->in[11];
  61       surf(s->out,s->in,s->seed);
  62       for (i = 0;i < 8;++i)
  63         s->sum[i] += s->out[i];
  64     }
  65   }
  66 }
  67
  68 static void surfpcs_out(s,h)
  69 surfpcs *s;
  70 unsigned char h[32];
  71 {
  72   int i;
  73   surfpcs_addlc(s,".",1);
  74   while (s->todo) surfpcs_addlc(s,"",1);
  75   for (i = 0;i < 8;++i) s->in[i] = s->sum[i];
  76   for (;i < 12;++i) s->in[i] = 0;
  77   surf(s->out,s->in,s->seed);
  78   for (i = 0;i < 32;++i) h[i] = outdata[end[i]];
  79 }
  80
  81 void makehash(indata,inlen,hash)
  82 char *indata;
  83 unsigned int inlen;
  84 char *hash;
  85         /* makes hash[COOKIE=20] from stralloc *indata, ignoring case and */
  86         /* SPACE/TAB */
  87 {
  88   unsigned char h[32];
  89   surfpcs s;
  90   uint32 seed[32];
  91   int i;
  92
  93   for (i = 0;i < 32;++i) seed[i] = 0;
  94   surfpcs_init(&s,seed);
  95   surfpcs_addlc(&s,indata,inlen);
  96   surfpcs_out(&s,h);
  97   for (i = 0;i < 20;++i)
  98     hash[i] = 'a' + (h[i] & 15);
  99 }
 100
 101 static stralloc dummy = {0};
 102
 103 void mkauthhash(s,len,h)
 104 char *s; unsigned int len; char *h;
 105 /* This is a string that should be the same for all messages from a given   */
 106 /* author. Doesn't have to be the real rfc822 address. We look for a '@'    */
 107 /* and grab everything up to the next '>', ' ', or ';'. We go back the same */
 108 /* way, then take everything up to the '@' or the first '-'. The latter     */
 109 /* avoids problems with posters that band their addresses.                  */
 110 {
 111   unsigned int i,j,k,l;
 112   register char ch;
 113
 114   j = k = l = 0;
 115   i = byte_rchr(s,len,'@');
 116   if (i < len) {                /* if not then i=sa->len, j=k=l=0 */
 117     j = i;
 118     while (++j < len) {         /* if not found, then j=sa->len */
 119       ch = s[j];
 120       if (ch == '>' || ch == ' ' || ch == ';') break;
 121     }
 122     k = i;
 123     while (k > 0) {             /* k <= i */
 124       ch = s[--k];
 125       if (ch == '<' || ch == ' ' || ch == ';') break;
 126     }
 127     l = k;                      /* k <= l <= i; */
 128     while (l < i && s[l] != '-') ++l;
 129     if (!stralloc_copyb(&dummy,s + k, l - k)) die_nomem();
 130     if (!stralloc_catb(&dummy,s + i, j - i)) die_nomem();
 131     makehash(dummy.s,dummy.len,h);
 132   } else                        /* use entire line if no '@' found */
 133     makehash(s,len,h);
 134 }
 135
 136