src/patches/dhcp-4.2.0-UseMulticast.patch

   1 diff -up dhcp-4.2.0/server/dhcpv6.c.UseMulticast dhcp-4.2.0/server/dhcpv6.c
   2 --- dhcp-4.2.0/server/dhcpv6.c.UseMulticast     2010-06-01 19:30:00.000000000 +0200
   3 +++ dhcp-4.2.0/server/dhcpv6.c  2010-07-21 16:17:30.000000000 +0200
   4 @@ -346,6 +346,48 @@ generate_new_server_duid(void) {
   5  }
   6
   7  /*
   8 + * Is the D6O_UNICAST option defined in dhcpd.conf ?
   9 + */
  10 +static isc_boolean_t unicast_option_defined;
  11 +
  12 +/*
  13 + * Did we already search dhcpd.conf for D6O_UNICAST option ?
  14 + * We need to store it here to not parse dhcpd.conf repeatedly.
  15 + */
  16 +static isc_boolean_t unicast_option_parsed = ISC_FALSE;
  17 +
  18 +
  19 +/*
  20 + * Is the D6O_UNICAST option defined in dhcpd.conf ?
  21 + */
  22 +isc_boolean_t
  23 +is_unicast_option_defined(void) {
  24 +       struct option_state *opt_state;
  25 +       struct option_cache *oc;
  26 +
  27 +       /*
  28 +        * If we are looking for the unicast option for the first time
  29 +        */
  30 +       if (unicast_option_parsed == ISC_FALSE) {
  31 +               unicast_option_parsed = ISC_TRUE;
  32 +               opt_state = NULL;
  33 +               if (!option_state_allocate(&opt_state, MDL)) {
  34 +                       log_fatal("No memory for option state.");
  35 +               }
  36 +
  37 +               execute_statements_in_scope(NULL, NULL, NULL, NULL, NULL,
  38 +                               opt_state, &global_scope, root_group, NULL);
  39 +
  40 +               oc = lookup_option(&dhcpv6_universe, opt_state, D6O_UNICAST);
  41 +               unicast_option_defined = (oc != NULL);
  42 +
  43 +               option_state_dereference(&opt_state, MDL);
  44 +       }
  45 +
  46 +       return (unicast_option_defined);
  47 +}
  48 +
  49 +/*
  50   * Get the client identifier from the packet.
  51   */
  52  isc_result_t
  53 @@ -1405,6 +1447,56 @@ lease_to_client(struct data_string *repl
  54                                                     reply.shared->group);
  55         }
  56
  57 +       /* reject unicast message, unless we set unicast option */
  58 +       if ((packet->unicast == ISC_TRUE) && !is_unicast_option_defined())
  59 +       /*
  60 +        * RFC3315 section 18.2.1 (Request):
  61 +        *
  62 +        * When the server receives a Request message via unicast from a client
  63 +        * to which the server has not sent a unicast option, the server
  64 +        * discards the Request message and responds with a Reply message
  65 +        * containing a Status Code option with the value UseMulticast, a Server
  66 +        * Identifier option containing the server's DUID, the Client Identifier
  67 +        * option from the client message, and no other options.
  68 +        *
  69 +        * Section 18.2.3 (Renew):
  70 +        *
  71 +        * When the server receives a Renew message via unicast from a client to
  72 +        * which the server has not sent a unicast option, the server discards
  73 +        * the Renew message and responds with a Reply message containing a
  74 +        * Status Code option with the value UseMulticast, a Server Identifier
  75 +        * option containing the server's DUID, the Client Identifier option
  76 +        * from the client message, and no other options.
  77 +        */
  78 +       {
  79 +               /* Set the UseMulticast status code. */
  80 +               if (!set_status_code(STATUS_UseMulticast,
  81 +                                       "Unicast not allowed by server.",
  82 +                                       reply.opt_state)) {
  83 +                       log_error("lease_to_client: Unable to set "
  84 +                                       "UseMulticast status code.");
  85 +                       goto exit;
  86 +               }
  87 +
  88 +               /* Rewind the cursor to the start. */
  89 +               reply.cursor = REPLY_OPTIONS_INDEX;
  90 +
  91 +               /*
  92 +                * Produce an reply that includes only:
  93 +                *
  94 +                * Status code.
  95 +                * Server DUID.
  96 +                * Client DUID.
  97 +                */
  98 +               reply.cursor += store_options6((char *)reply.buf.data +
  99 +                                       reply.cursor,
 100 +                                       sizeof(reply.buf) -
 101 +                                       reply.cursor,
 102 +                                       reply.opt_state, reply.packet,
 103 +                                       required_opts_NAA,
 104 +                                       NULL);
 105 +       } else if (no_resources_avail && (reply.ia_count != 0) &&
 106 +           (reply.packet->dhcpv6_msg_type == DHCPV6_SOLICIT))
 107         /*
 108          * RFC3315 section 17.2.2 (Solicit):
 109          *
 110 @@ -1429,8 +1521,6 @@ lease_to_client(struct data_string *repl
 111          * the server.
 112          * Sends a Renew/Rebind if the IA is not in the Reply message.
 113          */
 114 -       if (no_resources_avail && (reply.ia_count != 0) &&
 115 -           (reply.packet->dhcpv6_msg_type == DHCPV6_SOLICIT))
 116         {
 117                 /* Set the NoAddrsAvail status code. */
 118                 if (!set_status_code(STATUS_NoAddrsAvail,
 119 @@ -4128,7 +4218,6 @@ dhcpv6_solicit(struct data_string *reply
 120   * Very similar to Solicit handling, except the server DUID is required.
 121   */
 122
 123 -/* TODO: reject unicast messages, unless we set unicast option */
 124  static void
 125  dhcpv6_request(struct data_string *reply_ret, struct packet *packet) {
 126         struct data_string client_id;
 127 @@ -4443,7 +4532,6 @@ exit:
 128   * except for the error code of when addresses don't match.
 129   */
 130
 131 -/* TODO: reject unicast messages, unless we set unicast option */
 132  static void
 133  dhcpv6_renew(struct data_string *reply, struct packet *packet) {
 134         struct data_string client_id;
 135 @@ -4688,18 +4776,60 @@ iterate_over_ia_na(struct data_string *r
 136                 goto exit;
 137         }
 138
 139 -       snprintf(status_msg, sizeof(status_msg), "%s received.", packet_type);
 140 -       if (!set_status_code(STATUS_Success, status_msg, opt_state)) {
 141 -               goto exit;
 142 -       }
 143 +       /* reject unicast message, unless we set unicast option */
 144 +       if ((packet->unicast == ISC_TRUE) && !is_unicast_option_defined()) {
 145 +               /*
 146 +                * RFC3315 section 18.2.6 (Release):
 147 +                *
 148 +                * When the server receives a Release message via unicast from a client
 149 +                * to which the server has not sent a unicast option, the server
 150 +                * discards the Release message and responds with a Reply message
 151 +                * containing a Status Code option with value UseMulticast, a Server
 152 +                * Identifier option containing the server's DUID, the Client Identifier
 153 +                * option from the client message, and no other options.
 154 +                *
 155 +                * Section 18.2.7 (Decline):
 156 +                *
 157 +                * When the server receives a Decline message via unicast from a client
 158 +                * to which the server has not sent a unicast option, the server
 159 +                * discards the Decline message and responds with a Reply message
 160 +                * containing a Status Code option with the value UseMulticast, a Server
 161 +                * Identifier option containing the server's DUID, the Client Identifier
 162 +                * option from the client message, and no other options.
 163 +                */
 164 +               snprintf(status_msg, sizeof(status_msg),
 165 +                                "%s received unicast.", packet_type);
 166 +               if (!set_status_code(STATUS_UseMulticast, status_msg, opt_state)) {
 167 +                       goto exit;
 168 +               }
 169
 170 -       /*
 171 -        * Add our options that are not associated with any IA_NA or IA_TA.
 172 -        */
 173 -       reply_ofs += store_options6(reply_data+reply_ofs,
 174 -                                   sizeof(reply_data)-reply_ofs,
 175 +               /*
 176 +                * Produce an reply that includes only:
 177 +                *
 178 +                * Status code.
 179 +                * Server DUID.
 180 +                * Client DUID.
 181 +                */
 182 +               reply_ofs += store_options6(reply_data+reply_ofs,
 183 +                                   sizeof(reply_data)-reply_ofs,
 184                                     opt_state, packet,
 185 -                                   required_opts, NULL);
 186 +                                   required_opts_NAA, NULL);
 187 +
 188 +               goto return_reply;
 189 +       } else {
 190 +               snprintf(status_msg, sizeof(status_msg), "%s received.", packet_type);
 191 +               if (!set_status_code(STATUS_Success, status_msg, opt_state)) {
 192 +                       goto exit;
 193 +               }
 194 +
 195 +               /*
 196 +                * Add our options that are not associated with any IA_NA or IA_TA.
 197 +                */
 198 +               reply_ofs += store_options6(reply_data+reply_ofs,
 199 +                                           sizeof(reply_data)-reply_ofs,
 200 +                                           opt_state, packet,
 201 +                                           required_opts, NULL);
 202 +       }
 203
 204         /*
 205          * Loop through the IA_NA reported by the client, and deal with
 206 @@ -4838,6 +4968,7 @@ iterate_over_ia_na(struct data_string *r
 207         /*
 208          * Return our reply to the caller.
 209          */
 210 +return_reply:
 211         reply_ret->len = reply_ofs;
 212         reply_ret->buffer = NULL;
 213         if (!buffer_allocate(&reply_ret->buffer, reply_ofs, MDL)) {
 214 @@ -4883,7 +5014,6 @@ exit:
 215   * we still need to be aware of this possibility.
 216   */
 217
 218 -/* TODO: reject unicast messages, unless we set unicast option */
 219  /* TODO: IA_TA */
 220  static void
 221  dhcpv6_decline(struct data_string *reply, struct packet *packet) {
 222 @@ -5355,7 +5485,6 @@ exit:
 223   * Release means a client is done with the leases.
 224   */
 225
 226 -/* TODO: reject unicast messages, unless we set unicast option */
 227  static void
 228  dhcpv6_release(struct data_string *reply, struct packet *packet) {
 229         struct data_string client_id;