mdw@git.distorted.org.uk Git - userv-utils/blob - ipif/forwarder.h

   1 /*
   2  * Encrypting tunnel for userv-ipif tunnels, header file
   3  */
   4 /*
   5  * Copyright (C) 2000,2003 Ian Jackson
   6  * This file is part of ipif, part of userv-utils
   7  *
   8  * This is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with userv-utils; if not, write to the Free Software
  20  * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  21  */
  22
  23 #ifndef MECHS_H
  24 #define MECHS_H
  25
  26 #include <stdio.h>
  27 #include <time.h>
  28 #include <string.h>
  29 #include <sys/utsname.h>
  30
  31 #include "automech.h"
  32
  33 struct buffer {
  34   unsigned char *base;
  35   unsigned char *start;
  36   size_t size;
  37 };
  38
  39 struct mechdata;
  40
  41 typedef void mes_functype(struct mechdata **md_r, int *maxprefix_io, int *maxsuffix_io);
  42 typedef void mds_functype(struct mechdata **md_r);
  43
  44 typedef void menc_functype(struct mechdata *md, struct buffer*);
  45 typedef const char *mdec_functype(struct mechdata *md, struct buffer*);
  46
  47 struct mechanism {
  48   const char *name;
  49   mes_functype *encsetup;
  50   mds_functype *decsetup;
  51   menc_functype *encode;
  52   mdec_functype *decode;
  53 };
  54
  55 extern const struct mechanism *const mechanismlists[];
  56
  57 /* setup function may call getarg_xxx functions and then
  58  * reads/writes key material to/from fd
  59  *
  60  * setup_in function may increase maxprefix and maxsuffix
  61  * code functions modify buffer in place
  62  * decode function returns 0 meaning packet decoded ok,
  63  *  "" meaning discard it quietly, or message to print for verbose discard
  64  */
  65
  66 const char *getarg_string(void);
  67 unsigned long getarg_ulong(void);
  68
  69 #define PROGRAM "udptunnel-forwarder"
  70 extern char programid[];
  71
  72 void *buf_append(struct buffer *buf, size_t amount);
  73 void *buf_prepend(struct buffer *buf, size_t amount);
  74 void *buf_unappend(struct buffer *buf, size_t amount); /* may give 0 */
  75 void *buf_unprepend(struct buffer *buf, size_t amount); /* may give 0 */
  76
  77 void sysfail(const char *msg);
  78 void fail(const char *msg);
  79 void sysdiag(const char *msg);
  80 void diag(const char *msg);
  81
  82 extern const char *const *argv;
  83
  84 time_t now(void);
  85 void *xmalloc(size_t sz);
  86 void get_random(void *ptr, size_t sz);
  87 void random_key(void *ptr, size_t sz);
  88 void write_must(int fd, const void *p_in, int sz, const char *what);
  89 void read_must(int fd, void *p_in, int sz, const char *what);
  90
  91 void arg_assert_fail(const char *msg);
  92 #define arg_assert(v)  (v ? (void)0 : arg_assert_fail(#v))
  93
  94 #define XMALLOC(variable) ((variable)= xmalloc(sizeof(*(variable))))
  95
  96 #define BUF_UNSOMEEND(var,buf,sz,whichend) \
  97  do { var= whichend(buf,sz); if (!var) return "message truncated"; } while(0)
  98 #define BUF_UNAPPEND(var,buf,sz) BUF_UNSOMEEND(var,buf,sz,buf_unappend)
  99 #define BUF_UNPREPEND(var,buf,sz) BUF_UNSOMEEND(var,buf,sz,buf_unprepend)
 100
 101 #define STANDARD_MECHANISMLIST(mechstring,filename) \
 102  const struct mechanism mechlist_##filename []= {    \
 103    STANDARD_MECHANISM(mechstring,filename)          \
 104    { 0 }                                            \
 105  };
 106
 107 #define STANDARD_MECHANISM(mechstring,mechname) \
 108  { mechstring, mes_##mechname, mds_##mechname, menc_##mechname, mdec_##mechname },
 109
 110 #endif