Ari Saha | 79d7c25 | 2015-06-26 10:31:48 -0700 | [diff] [blame] | 1 | /* |
| 2 | * |
| 3 | * Copyright 2015 AT&T Foundry |
| 4 | * |
| 5 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | * you may not use this file except in compliance with the License. |
| 7 | * You may obtain a copy of the License at |
| 8 | * |
| 9 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | * |
| 11 | * Unless required by applicable law or agreed to in writing, software |
| 12 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | * See the License for the specific language governing permissions and |
| 15 | * limitations under the License. |
| 16 | * |
| 17 | */ |
| 18 | |
| 19 | package org.onosproject.aaa; |
| 20 | |
| 21 | import org.onlab.packet.MacAddress; |
| 22 | import org.onosproject.net.ConnectPoint; |
| 23 | import org.onosproject.xosintegration.VoltTenant; |
| 24 | import org.onosproject.xosintegration.VoltTenantService; |
| 25 | import org.slf4j.Logger; |
| 26 | import java.util.BitSet; |
| 27 | |
| 28 | import static org.slf4j.LoggerFactory.getLogger; |
| 29 | |
| 30 | /** |
| 31 | * AAA Finite State Machine. |
| 32 | */ |
| 33 | |
| 34 | class StateMachine { |
| 35 | //INDEX to identify the state in the transition table |
| 36 | static final int STATE_IDLE = 0; |
| 37 | static final int STATE_STARTED = 1; |
| 38 | static final int STATE_PENDING = 2; |
| 39 | static final int STATE_AUTHORIZED = 3; |
| 40 | static final int STATE_UNAUTHORIZED = 4; |
| 41 | |
| 42 | //INDEX to identify the transition in the transition table |
| 43 | static final int TRANSITION_START = 0; // --> started |
| 44 | static final int TRANSITION_REQUEST_ACCESS = 1; |
| 45 | static final int TRANSITION_AUTHORIZE_ACCESS = 2; |
| 46 | static final int TRANSITION_DENY_ACCESS = 3; |
| 47 | static final int TRANSITION_LOGOFF = 4; |
| 48 | |
| 49 | //map of access identifiers (issued at EAPOL START) |
| 50 | static BitSet bitSet = new BitSet(); |
| 51 | private final VoltTenantService voltService; |
| 52 | |
| 53 | private int identifier = -1; |
| 54 | private byte challengeIdentifier; |
| 55 | private byte[] challengeState; |
| 56 | private byte[] username; |
| 57 | private byte[] requestAuthenticator; |
| 58 | |
| 59 | // Supplicant connectivity info |
| 60 | protected ConnectPoint supplicantConnectpoint; |
| 61 | protected MacAddress supplicantAddress; |
| 62 | protected short vlanId; |
| 63 | |
| 64 | private String sessionId = null; |
| 65 | |
| 66 | private final Logger log = getLogger(getClass()); |
| 67 | |
| 68 | |
| 69 | private State[] states = { |
| 70 | new Idle(), new Started(), new Pending(), new Authorized(), new Unauthorized() |
| 71 | }; |
| 72 | |
| 73 | |
| 74 | //State transition table |
| 75 | /* |
| 76 | |
| 77 | state IDLE | STARTED | PENDING | AUTHORIZED | UNAUTHORIZED |
| 78 | //// |
| 79 | input |
| 80 | ---------------------------------------------------------------------------------------------------- |
| 81 | |
| 82 | START STARTED | _ | _ | _ | _ |
| 83 | |
| 84 | REQUEST_ACCESS _ | PENDING | _ | _ | _ |
| 85 | |
| 86 | AUTHORIZE_ACCESS _ | _ | AUTHORIZED | _ | _ |
| 87 | |
| 88 | DENY_ACCESS _ | - | UNAUTHORIZED | _ | _ |
| 89 | |
| 90 | LOGOFF _ | _ | _ | IDLE | IDLE |
| 91 | */ |
| 92 | |
| 93 | private int[] idleTransition = |
| 94 | {STATE_STARTED, STATE_IDLE, STATE_IDLE, STATE_IDLE, STATE_IDLE}; |
| 95 | private int[] startedTransition = |
| 96 | {STATE_STARTED, STATE_PENDING, STATE_STARTED, STATE_STARTED, STATE_STARTED}; |
| 97 | private int[] pendingTransition = |
| 98 | {STATE_PENDING, STATE_PENDING, STATE_AUTHORIZED, STATE_UNAUTHORIZED, STATE_PENDING}; |
| 99 | private int[] authorizedTransition = |
| 100 | {STATE_AUTHORIZED, STATE_AUTHORIZED, STATE_AUTHORIZED, STATE_AUTHORIZED, STATE_IDLE}; |
| 101 | private int[] unauthorizedTransition = |
| 102 | {STATE_UNAUTHORIZED, STATE_UNAUTHORIZED, STATE_UNAUTHORIZED, STATE_UNAUTHORIZED, STATE_IDLE}; |
| 103 | |
| 104 | //THE TRANSITION TABLE |
| 105 | private int[][] transition = |
| 106 | {idleTransition, startedTransition, pendingTransition, authorizedTransition, |
| 107 | unauthorizedTransition}; |
| 108 | |
| 109 | private int currentState = STATE_IDLE; |
| 110 | |
| 111 | |
| 112 | /** |
| 113 | * State Machine Constructor. |
| 114 | * @param sessionId Session Id represented by the switch dpid + port number |
| 115 | */ |
| 116 | public StateMachine(String sessionId, VoltTenantService voltService) { |
| 117 | log.info("Creating a new state machine for {}", sessionId); |
| 118 | this.sessionId = sessionId; |
| 119 | this.voltService = voltService; |
| 120 | |
| 121 | } |
| 122 | |
| 123 | /** |
| 124 | * Get the client id that is requesting for access. |
| 125 | * @return The client id. |
| 126 | */ |
| 127 | public String getSessionId() { |
| 128 | return this.sessionId; |
| 129 | } |
| 130 | |
| 131 | /** |
| 132 | * Create the identifier for the state machine (happens when goes to STARTED state). |
| 133 | */ |
| 134 | private void createIdentifier() throws StateMachineException { |
| 135 | log.debug("Creating Identifier."); |
| 136 | int index = -1; |
| 137 | |
| 138 | try { |
| 139 | //find the first available spot for identifier assignment |
| 140 | index = StateMachine.bitSet.nextClearBit(0); |
| 141 | |
| 142 | //there is a limit of 256 identifiers |
| 143 | if (index == 256) { |
| 144 | throw new StateMachineException("Cannot handle any new identifier. Limit is 256."); |
| 145 | } |
| 146 | } catch (IndexOutOfBoundsException e) { |
| 147 | throw new StateMachineException(e.getMessage()); |
| 148 | } |
| 149 | |
| 150 | log.info("Assigning identifier {}", index); |
| 151 | StateMachine.bitSet.set(index); |
| 152 | this.identifier = index; |
| 153 | } |
| 154 | |
| 155 | /** |
| 156 | * Set the challenge identifier and the state issued by the RADIUS. |
| 157 | * @param challengeIdentifier The challenge identifier set into the EAP packet from the RADIUS message. |
| 158 | * @param challengeState The challenge state from the RADIUS. |
| 159 | */ |
| 160 | protected void setChallengeInfo(byte challengeIdentifier, byte[] challengeState) { |
| 161 | this.challengeIdentifier = challengeIdentifier; |
| 162 | this.challengeState = challengeState; |
| 163 | } |
| 164 | /** |
| 165 | * Set the challenge identifier issued by the RADIUS on the access challenge request. |
| 166 | * @param challengeIdentifier The challenge identifier set into the EAP packet from the RADIUS message. |
| 167 | */ |
| 168 | protected void setChallengeIdentifier(byte challengeIdentifier) { |
| 169 | log.info("Set Challenge Identifier to {}", challengeIdentifier); |
| 170 | this.challengeIdentifier = challengeIdentifier; |
| 171 | } |
| 172 | |
| 173 | /** |
| 174 | * Get the challenge EAP identifier set by the RADIUS. |
| 175 | * @return The challenge EAP identifier. |
| 176 | */ |
| 177 | protected byte getChallengeIdentifier() { |
| 178 | return this.challengeIdentifier; |
| 179 | } |
| 180 | |
| 181 | |
| 182 | /** |
| 183 | * Set the challenge state info issued by the RADIUS. |
| 184 | * @param challengeState The challenge state from the RADIUS. |
| 185 | */ |
| 186 | protected void setChallengeState(byte[] challengeState) { |
| 187 | log.info("Set Challenge State"); |
| 188 | this.challengeState = challengeState; |
| 189 | } |
| 190 | |
| 191 | /** |
| 192 | * Get the challenge state set by the RADIUS. |
| 193 | * @return The challenge state. |
| 194 | */ |
| 195 | protected byte[] getChallengeState() { |
| 196 | return this.challengeState; |
| 197 | } |
| 198 | |
| 199 | /** |
| 200 | * Set the username. |
| 201 | * @param username The username sent to the RADIUS upon access request. |
| 202 | */ |
| 203 | protected void setUsername(byte[] username) { |
| 204 | this.username = username; |
| 205 | } |
| 206 | |
| 207 | |
| 208 | /** |
| 209 | * Get the username. |
| 210 | * @return The requestAuthenticator. |
| 211 | */ |
| 212 | protected byte[] getReqeustAuthenticator() { |
| 213 | return this.requestAuthenticator; |
| 214 | } |
| 215 | |
| 216 | /** |
| 217 | * Set the username. |
| 218 | * @param authenticator The username sent to the RADIUS upon access request. |
| 219 | */ |
| 220 | protected void setRequestAuthenticator(byte[] authenticator) { |
| 221 | this.requestAuthenticator = authenticator; |
| 222 | } |
| 223 | |
| 224 | |
| 225 | /** |
| 226 | * Get the username. |
| 227 | * @return The username. |
| 228 | */ |
| 229 | protected byte[] getUsername() { |
| 230 | return this.username; |
| 231 | } |
| 232 | |
| 233 | /** |
| 234 | * Return the identifier of the state machine. |
| 235 | * @return The state machine identifier. |
| 236 | */ |
| 237 | public byte getIdentifier() { |
| 238 | return (byte) this.identifier; |
| 239 | } |
| 240 | |
| 241 | |
| 242 | protected void deleteIdentifier() { |
| 243 | if (this.identifier != -1) { |
| 244 | log.info("Freeing up " + this.identifier); |
| 245 | //this state machine should be deleted and free up the identifier |
| 246 | StateMachine.bitSet.clear(this.identifier); |
| 247 | this.identifier = -1; |
| 248 | } |
| 249 | } |
| 250 | |
| 251 | |
| 252 | /** |
| 253 | * Move to the next state. |
| 254 | * @param msg |
| 255 | */ |
| 256 | private void next(int msg) { |
| 257 | currentState = transition[currentState][msg]; |
| 258 | log.info("Current State " + currentState); |
| 259 | } |
| 260 | |
| 261 | /** |
| 262 | * Client has requested the start action to allow network access. |
| 263 | */ |
| 264 | public void start() throws StateMachineException { |
| 265 | try { |
| 266 | states[currentState].start(); |
| 267 | //move to the next state |
| 268 | next(TRANSITION_START); |
| 269 | createIdentifier(); |
| 270 | } catch (StateMachineInvalidTransitionException e) { |
| 271 | e.printStackTrace(); |
| 272 | } |
| 273 | } |
| 274 | |
| 275 | /** |
| 276 | * An Identification information has been sent by the supplicant. |
| 277 | * Move to the next state if possible. |
| 278 | */ |
| 279 | public void requestAccess() throws StateMachineException { |
| 280 | try { |
| 281 | states[currentState].requestAccess(); |
| 282 | //move to the next state |
| 283 | next(TRANSITION_REQUEST_ACCESS); |
| 284 | } catch (StateMachineInvalidTransitionException e) { |
| 285 | e.printStackTrace(); |
| 286 | } |
| 287 | } |
| 288 | |
| 289 | /** |
| 290 | * RADIUS has accepted the identification. |
| 291 | * Move to the next state if possible. |
| 292 | */ |
| 293 | public void authorizeAccess() throws StateMachineException { |
| 294 | try { |
| 295 | states[currentState].radiusAccepted(); |
| 296 | //move to the next state |
| 297 | next(TRANSITION_AUTHORIZE_ACCESS); |
| 298 | |
| 299 | if (voltService != null) { |
| 300 | voltService.addTenant( |
| 301 | VoltTenant.builder() |
| 302 | .withHumanReadableName("VCPE-" + this.identifier) |
| 303 | .withId(this.identifier) |
| 304 | .withProviderService(1) |
| 305 | .withServiceSpecificId(String.valueOf(this.identifier)) |
| 306 | .withPort(this.supplicantConnectpoint) |
| 307 | .withVlanId(String.valueOf(this.vlanId)).build()); |
| 308 | } |
| 309 | |
| 310 | deleteIdentifier(); |
| 311 | } catch (StateMachineInvalidTransitionException e) { |
| 312 | e.printStackTrace(); |
| 313 | } |
| 314 | |
| 315 | } |
| 316 | |
| 317 | /** |
| 318 | * RADIUS has denied the identification. |
| 319 | * Move to the next state if possible. |
| 320 | */ |
| 321 | public void denyAccess() throws StateMachineException { |
| 322 | try { |
| 323 | states[currentState].radiusDenied(); |
| 324 | //move to the next state |
| 325 | next(TRANSITION_DENY_ACCESS); |
| 326 | deleteIdentifier(); |
| 327 | } catch (StateMachineInvalidTransitionException e) { |
| 328 | e.printStackTrace(); |
| 329 | } |
| 330 | } |
| 331 | |
| 332 | /** |
| 333 | * Logoff request has been requested. |
| 334 | * Move to the next state if possible. |
| 335 | */ |
| 336 | public void logoff() throws StateMachineException { |
| 337 | try { |
| 338 | states[currentState].logoff(); |
| 339 | //move to the next state |
| 340 | next(TRANSITION_LOGOFF); |
| 341 | } catch (StateMachineInvalidTransitionException e) { |
| 342 | e.printStackTrace(); |
| 343 | } |
| 344 | } |
| 345 | |
| 346 | /** |
| 347 | * Get the current state. |
| 348 | * @return The current state. Could be STATE_IDLE, STATE_STARTED, STATE_PENDING, STATE_AUTHORIZED, |
| 349 | * STATE_UNAUTHORIZED. |
| 350 | */ |
| 351 | public int getState() { |
| 352 | return currentState; |
| 353 | } |
| 354 | |
| 355 | |
| 356 | |
| 357 | public String toString() { |
| 358 | return ("sessionId: " + this.sessionId) + "\t" + ("identifier: " + this.identifier) + "\t" + |
| 359 | ("state: " + this.currentState); |
| 360 | } |
| 361 | } |
| 362 | |
| 363 | abstract class State { |
| 364 | private final Logger log = getLogger(getClass()); |
| 365 | |
| 366 | private String name = "State"; |
| 367 | |
| 368 | public void start() throws StateMachineInvalidTransitionException { |
| 369 | log.warn("START transition from this state is not allowed."); |
| 370 | } |
| 371 | public void requestAccess() throws StateMachineInvalidTransitionException { |
| 372 | log.warn("REQUEST ACCESS transition from this state is not allowed."); |
| 373 | } |
| 374 | public void radiusAccepted() throws StateMachineInvalidTransitionException { |
| 375 | log.warn("AUTHORIZE ACCESS transition from this state is not allowed."); |
| 376 | } |
| 377 | public void radiusDenied() throws StateMachineInvalidTransitionException { |
| 378 | log.warn("DENY ACCESS transition from this state is not allowed."); |
| 379 | } |
| 380 | public void logoff() throws StateMachineInvalidTransitionException { |
| 381 | log.warn("LOGOFF transition from this state is not allowed."); |
| 382 | } |
| 383 | } |
| 384 | |
| 385 | /** |
| 386 | * Idle state: supplicant is logged of from the network. |
| 387 | */ |
| 388 | class Idle extends State { |
| 389 | private final Logger log = getLogger(getClass()); |
| 390 | private String name = "IDLE_STATE"; |
| 391 | |
| 392 | public void start() { |
| 393 | log.info("Moving from IDLE state to STARTED state."); |
| 394 | } |
| 395 | } |
| 396 | |
| 397 | /** |
| 398 | * Started state: supplicant has entered the network and informed the authenticator. |
| 399 | */ |
| 400 | class Started extends State { |
| 401 | private final Logger log = getLogger(getClass()); |
| 402 | private String name = "STARTED_STATE"; |
| 403 | |
| 404 | public void requestAccess() { |
| 405 | log.info("Moving from STARTED state to PENDING state."); |
| 406 | } |
| 407 | } |
| 408 | |
| 409 | /** |
| 410 | * Pending state: supplicant has been identified by the authenticator but has not access yet. |
| 411 | */ |
| 412 | class Pending extends State { |
| 413 | private final Logger log = getLogger(getClass()); |
| 414 | private String name = "PENDING_STATE"; |
| 415 | |
| 416 | public void radiusAccepted() { |
| 417 | log.info("Moving from PENDING state to AUTHORIZED state."); |
| 418 | } |
| 419 | |
| 420 | public void radiusDenied() { |
| 421 | log.info("Moving from PENDING state to UNAUTHORIZED state."); |
| 422 | } |
| 423 | } |
| 424 | |
| 425 | /** |
| 426 | * Authorized state: supplicant port has been accepted, access is granted. |
| 427 | */ |
| 428 | class Authorized extends State { |
| 429 | private final Logger log = getLogger(getClass()); |
| 430 | private String name = "AUTHORIZED_STATE"; |
| 431 | |
| 432 | public void logoff() { |
| 433 | |
| 434 | log.info("Moving from AUTHORIZED state to IDLE state."); |
| 435 | } |
| 436 | } |
| 437 | |
| 438 | /** |
| 439 | * Unauthorized state: supplicant port has been rejected, access is denied. |
| 440 | */ |
| 441 | class Unauthorized extends State { |
| 442 | private final Logger log = getLogger(getClass()); |
| 443 | private String name = "UNAUTHORIZED_STATE"; |
| 444 | |
| 445 | public void logoff() { |
| 446 | log.info("Moving from UNAUTHORIZED state to IDLE state."); |
| 447 | } |
| 448 | } |
| 449 | |
| 450 | |
| 451 | /** |
| 452 | * Exception for the State Machine. |
| 453 | */ |
| 454 | class StateMachineException extends Exception { |
| 455 | public StateMachineException(String message) { |
| 456 | super(message); |
| 457 | |
| 458 | } |
| 459 | } |
| 460 | /** |
| 461 | * Exception raised when the transition from one state to another is invalid. |
| 462 | */ |
| 463 | class StateMachineInvalidTransitionException extends StateMachineException { |
| 464 | public StateMachineInvalidTransitionException(String message) { |
| 465 | super(message); |
| 466 | } |
| 467 | } |