dhcp/patches/0024-dhcp-duid_uuid.patch

   1 diff -up dhcp-4.3.4/client/dhclient.c.duid_uuid dhcp-4.3.4/client/dhclient.c
   2 --- dhcp-4.3.4/client/dhclient.c.duid_uuid      2016-04-29 12:58:14.846150838 +0200
   3 +++ dhcp-4.3.4/client/dhclient.c        2016-04-29 12:58:14.851150839 +0200
   4 @@ -3868,6 +3868,59 @@ write_options(struct client_state *clien
   5         }
   6  }
   7
   8 +int unhexchar(char c) {
   9 +
  10 +       if (c >= '0' && c <= '9')
  11 +               return c - '0';
  12 +
  13 +       if (c >= 'a' && c <= 'f')
  14 +               return c - 'a' + 10;
  15 +
  16 +       if (c >= 'A' && c <= 'F')
  17 +               return c - 'A' + 10;
  18 +
  19 +       return -1;
  20 +}
  21 +
  22 +isc_result_t
  23 +read_uuid(u_int8_t* uuid) {
  24 +       const char *id_fname = "/etc/machine-id";
  25 +       char id[32];
  26 +       size_t nread;
  27 +       FILE * file = fopen( id_fname , "r");
  28 +       if (!file) {
  29 +               log_debug("Cannot open %s", id_fname);
  30 +               return ISC_R_IOERROR;
  31 +       }
  32 +       nread = fread(id, 1, sizeof id, file);
  33 +       fclose(file);
  34 +
  35 +       if (nread < 32) {
  36 +               log_debug("Not enough data in %s", id_fname);
  37 +               return ISC_R_IOERROR;
  38 +       }
  39 +
  40 +       for (int j = 0; j < 16; j++) {
  41 +               int a, b;
  42 +
  43 +               a = unhexchar(id[j*2]);
  44 +               b = unhexchar(id[j*2+1]);
  45 +
  46 +               if (a < 0 || b < 0) {
  47 +                       log_debug("Wrong data in %s", id_fname);
  48 +                        return ISC_R_IOERROR;
  49 +               }
  50 +               uuid[j] = a << 4 | b;
  51 +       }
  52 +
  53 +       /* Set UUID version to 4 --- truly random generation */
  54 +       uuid[6] = (uuid[6] & 0x0F) | 0x40;
  55 +       /* Set the UUID variant to DCE */
  56 +       uuid[8] = (uuid[8] & 0x3F) | 0x80;
  57 +
  58 +       return ISC_R_SUCCESS;
  59 +}
  60 +
  61  /*
  62   * The "best" default DUID, since we cannot predict any information
  63   * about the system (such as whether or not the hardware addresses are
  64 @@ -3888,6 +3941,7 @@ form_duid(struct data_string *duid, cons
  65         struct interface_info *ip;
  66         int len;
  67         char *str;
  68 +       u_int8_t uuid[16];
  69
  70         /* For now, just use the first interface on the list. */
  71         ip = interfaces;
  72 @@ -3908,9 +3962,16 @@ form_duid(struct data_string *duid, cons
  73             (ip->hw_address.hlen > sizeof(ip->hw_address.hbuf)))
  74                 log_fatal("Impossible hardware address length at %s:%d.", MDL);
  75
  76 -       if (duid_type == 0)
  77 -               duid_type = stateless ? DUID_LL : DUID_LLT;
  78 -
  79 +       if (duid_type == 0) {
  80 +               if (read_uuid(uuid) == ISC_R_SUCCESS)
  81 +                   duid_type = DUID_UUID;
  82 +               else
  83 +                   duid_type = stateless ? DUID_LL : DUID_LLT;
  84 +       }
  85 +
  86 +       if (duid_type == DUID_UUID)
  87 +               len = 2 + sizeof (uuid);
  88 +       else {
  89         /*
  90          * 2 bytes for the 'duid type' field.
  91          * 2 bytes for the 'htype' field.
  92 @@ -3921,13 +3982,18 @@ form_duid(struct data_string *duid, cons
  93         len = 4 + (ip->hw_address.hlen - 1);
  94         if (duid_type == DUID_LLT)
  95                 len += 4;
  96 +       }
  97         if (!buffer_allocate(&duid->buffer, len, MDL))
  98                 log_fatal("no memory for default DUID!");
  99         duid->data = duid->buffer->data;
 100         duid->len = len;
 101
 102 +       if (duid_type == DUID_UUID) {
 103 +               putUShort(duid->buffer->data, DUID_UUID);
 104 +               memcpy(duid->buffer->data + 2, uuid, sizeof(uuid));
 105 +       }
 106         /* Basic Link Local Address type of DUID. */
 107 -       if (duid_type == DUID_LLT) {
 108 +       else if (duid_type == DUID_LLT) {
 109                 putUShort(duid->buffer->data, DUID_LLT);
 110                 putUShort(duid->buffer->data + 2, ip->hw_address.hbuf[0]);
 111                 putULong(duid->buffer->data + 4, cur_time - DUID_TIME_EPOCH);