mdw@git.distorted.org.uk Git - tripe/blob - server/servutil.c

   1 /* -*-c-*-
   2  *
   3  * Various handy server-only utilities
   4  *
   5  * (c) 2001 Straylight/Edgeware
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of Trivial IP Encryption (TrIPE).
  11  *
  12  * TrIPE is free software: you can redistribute it and/or modify it under
  13  * the terms of the GNU General Public License as published by the Free
  14  * Software Foundation; either version 3 of the License, or (at your
  15  * option) any later version.
  16  *
  17  * TrIPE is distributed in the hope that it will be useful, but WITHOUT
  18  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  19  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  20  * for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with TrIPE.  If not, see <https://www.gnu.org/licenses/>.
  24  */
  25
  26 /*----- Header files ------------------------------------------------------*/
  27
  28 #include "tripe.h"
  29
  30 /*----- Global variables --------------------------------------------------*/
  31
  32 octet buf_i[PKBUFSZ], buf_o[PKBUFSZ], buf_t[PKBUFSZ], buf_u[PKBUFSZ];
  33
  34 /*----- Main code ---------------------------------------------------------*/
  35
  36 /* --- @timestr@ --- *
  37  *
  38  * Arguments:   @time_t t@ = a time to convert
  39  *
  40  * Returns:     A pointer to a textual representation of the time.
  41  *
  42  * Use:         Converts a time to a textual representation.  Corrupts
  43  *              @buf_u@.
  44  */
  45
  46 const char *timestr(time_t t)
  47 {
  48   struct tm *tm;
  49   if (!t)
  50     return ("NEVER");
  51   tm = localtime(&t);
  52   strftime((char *)buf_u, sizeof(buf_u), "%Y-%m-%dT%H:%M:%S", tm);
  53   return ((const char *)buf_u);
  54 }
  55
  56 /* --- @mystrieq@ --- *
  57  *
  58  * Arguments:   @const char *x, *y@ = two strings
  59  *
  60  * Returns:     True if @x@ and @y are equal, up to case.
  61  */
  62
  63 int mystrieq(const char *x, const char *y)
  64 {
  65   for (;;) {
  66     if (!*x && !*y) return (1);
  67     if (tolower((unsigned char)*x) != tolower((unsigned char)*y))
  68       return (0);
  69     x++; y++;
  70   }
  71 }
  72
  73 /* --- @seq_reset@ --- *
  74  *
  75  * Arguments:   @seqwin *s@ = sequence-checking window
  76  *
  77  * Returns:     ---
  78  *
  79  * Use:         Resets a sequence number window.
  80  */
  81
  82 void seq_reset(seqwin *s) { s->seq = 0; s->win = 0; }
  83
  84 /* --- @seq_check@ --- *
  85  *
  86  * Arguments:   @seqwin *s@ = sequence-checking window
  87  *              @uint32 q@ = sequence number to check
  88  *              @const char *service@ = service to report message from
  89  *
  90  * Returns:     Zero on success, nonzero if the sequence number was bad.
  91  *
  92  * Use:         Checks a sequence number against the window, updating things
  93  *              as necessary.
  94  */
  95
  96 int seq_check(seqwin *s, uint32 q, const char *service)
  97 {
  98   uint32 qbit;
  99   uint32 n;
 100
 101   if (q < s->seq) {
 102     a_warn(service, "replay", "old-sequence", A_END);
 103     return (-1);
 104   }
 105   if (q >= s->seq + SEQ_WINSZ) {
 106     n = q - (s->seq + SEQ_WINSZ - 1);
 107     if (n < SEQ_WINSZ)
 108       s->win >>= n;
 109     else
 110       s->win = 0;
 111     s->seq += n;
 112   }
 113   qbit = 1 << (q - s->seq);
 114   if (s->win & qbit) {
 115     a_warn(service, "replay", "duplicated-sequence", A_END);
 116     return (-1);
 117   }
 118   s->win |= qbit;
 119   return (0);
 120 }
 121
 122 /*----- That's all, folks -------------------------------------------------*/