src/uuid.c

   1 /**
   2  * @file uuid.c
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  17  */
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20 #include <string.h>
  21
  22 #include <fcntl.h>
  23 #include <unistd.h>
  24
  25
  26 #ifndef _WIN32
  27 #include <sys/ioctl.h>
  28 #include <sys/types.h>
  29 #include <sys/socket.h>
  30 #include <netinet/in.h>
  31 #include <net/if.h>
  32 #else
  33 #ifdef _DLL
  34 #define _WS2TCPIP_H_
  35 #define _WINSOCK2API_
  36 #define _LIBC_INTERNAL_
  37 #endif /* _DLL */
  38 #include "internal.h"
  39 #endif /* _WIN32 */
  40
  41 #include <cipher.h>
  42 #include <glib.h>
  43 #include <glib/gprintf.h>
  44 #include "uuid.h"
  45
  46 static const char *epid_ns_uuid = "fcacfb03-8a73-46ef-91b1-e5ebeeaba4fe";
  47
  48 #define UUID_OFFSET_TO_LAST_SEGMENT 24
  49
  50 void readUUID(const char *string, sipe_uuid_t *uuid)
  51 {
  52         int i;
  53         sscanf(string, "%08x-%04hx-%04hx-%02hhx%02hhx-", &uuid->time_low
  54                         , &uuid->time_mid, &uuid->time_hi_and_version
  55                         , &uuid->clock_seq_hi_and_reserved
  56                         , &uuid->clock_seq_low );
  57
  58         for(i=0;i<6;i++)
  59         {
  60                 sscanf(&string[UUID_OFFSET_TO_LAST_SEGMENT+i*2], "%02hhx", &uuid->node[i]);
  61         }
  62 }
  63
  64 void printUUID(sipe_uuid_t *uuid, char *string)
  65 {
  66         int i;
  67         size_t pos;
  68         sprintf(string, "%08x-%04x-%04x-%02x%02x-", uuid->time_low
  69                         , uuid->time_mid, uuid->time_hi_and_version
  70                         , uuid->clock_seq_hi_and_reserved
  71                         , uuid->clock_seq_low
  72                         );
  73         pos = strlen(string);
  74         for(i=0;i<6;i++)
  75         {
  76                 pos += sprintf(&string[pos], "%02x", uuid->node[i]);
  77         }
  78 }
  79
  80 void createUUIDfromHash(sipe_uuid_t *uuid, const unsigned char *hash)
  81 {
  82         memcpy(uuid, hash, sizeof(sipe_uuid_t));
  83         uuid->time_hi_and_version &= 0x0FFF;
  84         uuid->time_hi_and_version |= 0x5000;
  85         uuid->clock_seq_hi_and_reserved &= 0x3F;
  86         uuid->clock_seq_hi_and_reserved |= 0x80;
  87 }
  88
  89 char *generateUUIDfromEPID(const gchar *epid)
  90 {
  91         sipe_uuid_t result;
  92         PurpleCipherContext *ctx;
  93         unsigned char hash[20];
  94         char buf[512];
  95
  96         readUUID(epid_ns_uuid, &result);
  97         memcpy(buf, &result, sizeof(sipe_uuid_t));
  98         strcpy(&buf[sizeof(sipe_uuid_t)], epid);
  99
 100         ctx = purple_cipher_context_new_by_name("sha1", NULL);
 101         purple_cipher_context_append(ctx, (guchar *) buf, strlen(buf));
 102         purple_cipher_context_digest(ctx, sizeof(hash), hash, NULL);
 103         purple_cipher_context_destroy(ctx);
 104
 105         createUUIDfromHash(&result, hash);
 106         printUUID(&result, buf);
 107         return g_strdup(buf);
 108 }
 109
 110 /**
 111  * Generates epid from user SIP URI, hostname and IP address.
 112  * Thus epid will be the same each start and
 113  * not needed to be persistent.
 114  *
 115  * Using MAC address proved to be poorly portable solution.
 116  */
 117 char *sipe_get_epid(const char *self_sip_uri,
 118                            const char *hostname,
 119                            const char *ip_address)
 120 {
 121 #define SIPE_EPID_HASH_START 15
 122 #define SIPE_EPID_HASH_END   20
 123 #define SIPE_EPID_LENGTH     (2 * (SIPE_EPID_HASH_END - SIPE_EPID_HASH_START + 1))
 124
 125         int i,j;
 126         PurpleCipherContext *ctx;
 127         unsigned char hash[SIPE_EPID_HASH_END];
 128         char out[SIPE_EPID_LENGTH + 1];
 129         char *buf = g_strdup_printf("%s:%s:%s", self_sip_uri, hostname, ip_address);
 130
 131         ctx = purple_cipher_context_new_by_name("sha1", NULL);
 132         purple_cipher_context_append(ctx, (guchar *)buf, strlen(buf));
 133         purple_cipher_context_digest(ctx, sizeof(hash), hash, NULL);
 134         purple_cipher_context_destroy(ctx);
 135
 136         for (i = SIPE_EPID_HASH_START, j = 0;
 137              i <= SIPE_EPID_HASH_END;
 138              i++, j += 2) {
 139                 g_sprintf(&out[j], "%02x", hash[i]);
 140         }
 141         out[SIPE_EPID_LENGTH] = 0;
 142
 143         g_free(buf);
 144         return g_strdup(out);
 145 }
 146
 147 /*
 148   Local Variables:
 149   mode: c
 150   c-file-style: "bsd"
 151   indent-tabs-mode: t
 152   tab-width: 8
 153   End:
 154 */