summaryrefslogtreecommitdiff
path: root/ot_accesslist.c
blob: e8ff74c01ac79b66a7bc17a934a318f2140b7dae (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
/* This software was written by Dirk Engling <erdgeist@erdgeist.org>
   It is considered beerware. Prost. Skol. Cheers or whatever.

   $id$ */

/* System */
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <signal.h>
#include <unistd.h>

/* Libowfat */
#include "byte.h"
#include "scan.h"
#include "ip6.h"
#include "mmap.h"

/* Opentracker */
#include "trackerlogic.h"
#include "ot_accesslist.h"
#include "ot_vector.h"

/* GLOBAL VARIABLES */
#ifdef WANT_ACCESSLIST
       char    *g_accesslist_filename;
static ot_hash *g_accesslist;
static size_t   g_accesslist_size;

static int vector_compare_hash(const void *hash1, const void *hash2 ) {
  return memcmp( hash1, hash2, OT_HASH_COMPARE_SIZE );
}

void accesslist_deinit( void ) {
  free( g_accesslist );
  g_accesslist = 0;
  g_accesslist_size = 0;
}

/* Read initial access list */
static void accesslist_readfile( int sig ) {
  ot_hash *info_hash, *accesslist_new = NULL, *accesslist_old;
  char    *map, *map_end, *read_offs;
  size_t   maplen;

  if( sig != SIGHUP ) return;

  if( ( map = mmap_read( g_accesslist_filename, &maplen ) ) == NULL ) {
    char *wd = getcwd( NULL, 0 );
    fprintf( stderr, "Warning: Can't open accesslist file: %s (but will try to create it later, if necessary and possible).\nPWD: %s\n", g_accesslist_filename, wd );
    free( wd );
    return;
  }

  /* You need at least 41 bytes to pass an info_hash, make enough room
     for the maximum amount of them */
  info_hash = accesslist_new = malloc( ( maplen / 41 ) * 20 );
  if( !accesslist_new ) {
    fprintf( stderr, "Warning: Not enough memory to allocate %zd bytes for accesslist buffer. May succeed later.\n", ( maplen / 41 ) * 20 );
    return;
  }
  
  /* No use to scan if there's not enough room for another full info_hash */
  map_end = map + maplen - 40;
  read_offs = map;

  /* We do ignore anything that is not of the form "^[:xdigit:]{40}[^:xdigit:].*" */
  while( read_offs < map_end ) {
    int i;
    for( i=0; i<(int)sizeof(ot_hash); ++i ) {
      int eger = 16 * scan_fromhex( read_offs[ 2*i ] ) + scan_fromhex( read_offs[ 1 + 2*i ] );
      if( eger < 0 )
        continue;
      (*info_hash)[i] = eger;
    }

    read_offs += 40;

    /* Append accesslist to accesslist vector */
    if( scan_fromhex( *read_offs ) < 0 )
      ++info_hash;

    /* Find start of next line */
    while( read_offs < map_end && *(read_offs++) != '\n' );
  }
//#ifdef _DEBUG
  fprintf( stderr, "Added %d info_hashes to accesslist\n", info_hash - accesslist_new );
//#endif

  mmap_unmap( map, maplen);

  qsort( accesslist_new, info_hash - accesslist_new, sizeof( *info_hash ), vector_compare_hash );

  /* Now exchange the accesslist vector in the least race condition prone way */
  g_accesslist_size = 0;
  accesslist_old    = g_accesslist;
  g_accesslist      = accesslist_new;
  g_accesslist_size = info_hash - accesslist_new;
  free( accesslist_old );  
}

int accesslist_hashisvalid( ot_hash hash ) {
  void *exactmatch = bsearch( hash, g_accesslist, g_accesslist_size, OT_HASH_COMPARE_SIZE, vector_compare_hash );

#ifdef WANT_ACCESSLIST_BLACK
  return exactmatch == NULL;
#else
  return exactmatch != NULL;
#endif
}

void accesslist_init( ) {
  /* Passing "0" since read_blacklist_file also is SIGHUP handler */
  if( g_accesslist_filename ) {
    accesslist_readfile( SIGHUP );
    signal( SIGHUP, accesslist_readfile );
  }
}
#endif

static ot_ip6         g_adminip_addresses[OT_ADMINIP_MAX];
static ot_permissions g_adminip_permissions[OT_ADMINIP_MAX];
static unsigned int   g_adminip_count = 0;

int accesslist_blessip( ot_ip6 ip, ot_permissions permissions ) {
  if( g_adminip_count >= OT_ADMINIP_MAX )
    return -1;

  memcpy(g_adminip_addresses + g_adminip_count,ip,sizeof(ot_ip6));
  g_adminip_permissions[ g_adminip_count++ ] = permissions;

#ifdef _DEBUG
  {
    char _debug[512];
    int off = snprintf( _debug, sizeof(_debug), "Blessing ip address " );
    off += fmt_ip6c(_debug+off, ip );

    if( permissions & OT_PERMISSION_MAY_STAT       ) off += snprintf( _debug+off, 512-off, " may_fetch_stats" );
    if( permissions & OT_PERMISSION_MAY_LIVESYNC   ) off += snprintf( _debug+off, 512-off, " may_sync_live" );
    if( permissions & OT_PERMISSION_MAY_FULLSCRAPE ) off += snprintf( _debug+off, 512-off, " may_fetch_fullscrapes" );
    if( permissions & OT_PERMISSION_MAY_PROXY      ) off += snprintf( _debug+off, 512-off, " may_proxy" );
    if( !permissions ) off += snprintf( _debug+off, sizeof(_debug)-off, " nothing\n" );
    _debug[off++] = '.';
    write( 2, _debug, off );
  }
#endif

  return 0;
}

int accesslist_isblessed( ot_ip6 ip, ot_permissions permissions ) {
  unsigned int i;
  for( i=0; i<g_adminip_count; ++i )
    if( !memcmp( g_adminip_addresses + i, ip, sizeof(ot_ip6)) && ( g_adminip_permissions[ i ] & permissions ) )
      return 1;
  return 0;
}

const char *g_version_accesslist_c = "$Source$: $Revision$\n";