100 TInet6HeaderIP ip6; |
101 TInet6HeaderIP ip6; |
101 }; |
102 }; |
102 }; |
103 }; |
103 |
104 |
104 |
105 |
105 // RMBufPacketPeek |
|
106 // *************** |
|
107 class RMBufPacketPeek : public RMBufChain |
|
108 /** |
|
109 Extends RMBufChain to add functions to read packet data as a descriptor |
|
110 and as an IP header. |
|
111 |
|
112 The RMBufChain is assumed to contain the raw packet, without |
|
113 the info block prepended (e.g. if this class is used for RMBufPacketBase |
|
114 derived handle, it must be in "unpacked" state). |
|
115 |
|
116 @since v7.0 |
|
117 @publishedAll |
|
118 @released |
|
119 */ |
|
120 { |
|
121 public: |
|
122 IMPORT_C TPtr8 Access(TInt aSize, TUint aOffset = 0); |
|
123 IMPORT_C TIpHeader *GetIpHeader(); |
|
124 }; |
|
125 |
|
126 // TPacketHead |
|
127 // *********** |
|
128 class TPacketHead |
|
129 /** |
|
130 Storage for some precomputed information for an outbound packet flow. |
|
131 |
|
132 The outbound TPacketHead is part of the flow context (CFlowContext). |
|
133 |
|
134 The CFlowContext::Connect initializes the content from the parameters |
|
135 of the flow (TFlowInfo) and runs the connection process.. The connection |
|
136 process (MIp6Hook::OpenL and MFlowHook::ReadyL phases) completes the |
|
137 information. After this, as long as the flow is connected, the content |
|
138 is mostly frozen and <b>must not be modified by anyone</b>. |
|
139 |
|
140 When there is a need to change any flow information, the changes must |
|
141 be done to the flow parameters (and not to TPacketHead). The change of |
|
142 flow parameters also sets the CFlowContext::iChanged flag, and this |
|
143 eventually causes a new CFlowContext::Connect, which re-initializes |
|
144 the TPacketHead with the new information. |
|
145 |
|
146 For each field in the TPacketHead, the hook writer must follow the |
|
147 basic rule (only for fields that it intends to change): |
|
148 |
|
149 - if some field is changed in MIp6Hook::OpenL, then the previous |
|
150 value should be restored in the MFlowHook::ReadyL. |
|
151 - an exeception: the hook must omit the restore, if the |
|
152 previous value was unspecified value (for example, the source |
|
153 address). |
|
154 - the content of #iPacket (and #iOffset) are special: they cannot |
|
155 be modified in the MIp6Hook::OpenL phase. A hook can |
|
156 modify them only in the MFlowHook::ReadyL phase. And, if the hook |
|
157 is adding an IP header for tunneling, it must save the current content |
|
158 of these fields in the ReadyL function, and then clear out the fields |
|
159 (it must make the iPacket empty and zero iOffset). The hook must add |
|
160 the saved iPacket content below the added tunnel header in |
|
161 MFlowHook::ApplyL . |
|
162 |
|
163 @since v7.0 |
|
164 @publishedAll |
|
165 @released |
|
166 */ |
|
167 { |
|
168 public: |
|
169 IMPORT_C TBool ExtHdrGet(TInt aType, TInt& aOfs, TInt& aLen); |
|
170 IMPORT_C TBool ExtHdrGetOrPrependL(TInt aType, TInt& aOfs, TInt& aLen); |
|
171 IMPORT_C TBool ExtHdrGetOrAppendL(TInt aType, TInt& aOfs, TInt& aLen); |
|
172 IMPORT_C void AddDestinationOptionL(const TPtrC8& aOption, TUint8 aAlign=0, TUint8 aModulo=4); |
|
173 IMPORT_C void AddDestinationOptionL(const TUint8* aOption, TUint8 aLen, TUint8 aAlign=0, TUint8 aModulo=4); |
|
174 |
|
175 public: |
|
176 /** |
|
177 "Virtual" IP header. The IPv6 header stucture is used, but the same |
|
178 format is <b>also</b> used for the IPv4 destinations (Version() == 4, |
|
179 even though the header format is still IPv6!) |
|
180 |
|
181 This header is initialized in the beginning of the OpenL phase |
|
182 as follows: |
|
183 @li Version = 0 |
|
184 @li Traffic Class, copied from the flow iOptions.iTrafficClass |
|
185 @li Flow Label = 0 |
|
186 @li Payload Length = 0 (dummy field, not used) |
|
187 @li Next Header, copied from the flow iProtocol |
|
188 @li Hop Limit, copied from the flow iOptions.iHopLimit |
|
189 @li Src Address, copied from the flow Local Address (usually unspecified) |
|
190 @li Dst Address, copied from the flow Remote Address |
|
191 |
|
192 At beginning of the ReadyL phase (= at end of OpenL), the destination |
|
193 address (and iDstId) are used to find a route on the interface. Depending |
|
194 on whether this address is IPv4 (mapped) or IPv6, the Version field is set |
|
195 accordingly to either 4 or 6. |
|
196 |
|
197 After succesfull completion of the ReadyL, this used for *each* packet |
|
198 which needs an IP header to be generated on send. The Version() determines |
|
199 whether IPv4 or IPv6 frame is to be generated (this is the initial |
|
200 header in the packet, *before* running outbound ApplyL hooks): |
|
201 |
|
202 @verbatim |
|
203 IPv6 IPv4 |
|
204 Version == 6 ==4 |
|
205 Traffic Class used as is used as TOS |
|
206 Flow Label used as is ignored |
|
207 Payload Length ignored ignored |
|
208 Next Header used as is used as Protocol |
|
209 Hop Limit used as is used as TTL |
|
210 Src Address used as is used as IPv4 mapped |
|
211 Dst Address used as is used as IPv4 mapped |
|
212 @endverbatim |
|
213 */ |
|
214 TInet6HeaderIP ip6; |
|
215 /** |
|
216 Contains the scope id associated with the destination address |
|
217 which is stored in #ip6 Dst Address. This id and address must |
|
218 always be considered as a unit. Logically, any change changes |
|
219 both values. |
|
220 |
|
221 iDstId is initialized from the flow context TFlowInfo::iRemote.Scope() at |
|
222 beginning of the flow connect phase. If application does not define |
|
223 this scope id, then the system will attempt to choose a default value |
|
224 at beginning of the connect phase. If the default cannot be determined, |
|
225 the flow is put into pending state (and no connect happens). |
|
226 |
|
227 @par MIp6Hook::OpenL |
|
228 On entry to the OpenL, the iDstId is always non-zero and destination |
|
229 address is specified. If a hook changes the destination address in |
|
230 OpenL method, it must provide the correct id value |
|
231 which goes with the new destination. If it cannot do this, it |
|
232 must either abort the connect by leaving with an error state, or it |
|
233 can leave with PENDING (> 0) status to signal there is no route |
|
234 for the new destination. |
|
235 If the stack cannot find suitable interface for the destination, then |
|
236 it aborts the connect phase, and the flow is placed into holding state. |
|
237 |
|
238 @note |
|
239 Only a tunneling hook can safely change the destination |
|
240 address (a use of routing header can also be a kind of |
|
241 tunneling). |
|
242 |
|
243 @par MFlowHook::ReadyL |
|
244 If the hook changed the destination address (or id) in the OpenL, |
|
245 the ReadyL must restore the original values back. |
|
246 |
|
247 */ |
|
248 TUint32 iDstId; |
|
249 /** |
|
250 Contains the scope id associated with the source address |
|
251 which is stored in #ip6 Src address. This is defined when the source |
|
252 address is defined, and otherwise undefined. |
|
253 |
|
254 iSrcId is initialized from TFlowInfo::iLocal.Scope() at beginning of the |
|
255 flow connect phase. If application defines the source address, |
|
256 but does not specify this scope id, then the system chooses |
|
257 the id based on the interface defined by the source address. |
|
258 If scope and address are both specified, they must match the |
|
259 selected interface. |
|
260 |
|
261 @par MIp6Hook::OpenL |
|
262 On entry to the OpenL, the iSrcId (and source address) may be |
|
263 undefined (#iSourceSet = 0). If defined (iSourceSet = 1), then |
|
264 both address and iSrcId are defined (iSrcId != 0). A hook may |
|
265 force a reselection of the source just by zeroing the |
|
266 iSourceSet. |
|
267 |
|
268 @par MFlowHook::ReadyL |
|
269 If the hook changed the source address (or id) in the OpenL, |
|
270 the ReadyL must restore the original values back, but only |
|
271 if the original value was defined (#iSourceSet = 1 in OpenL). |
|
272 */ |
|
273 TUint32 iSrcId; |
|
274 /** |
|
275 The source address has been set. |
|
276 |
|
277 This bit indicates whether the value stored in #ip6 src field |
|
278 and #iSrcId is to be used as a source address as is. |
|
279 |
|
280 Initialized from TFlowInfo::iLocalSet, which tells whether user |
|
281 specified tbe source address or not (e.g used RSocket Bind method). |
|
282 The stack checks the value after each MIp6Hook::OpenL call, and |
|
283 if the flag is set, the source in ip6 is used as is. If the flag |
|
284 is zero, then the stack performs the normal source address selection |
|
285 based on the current destination address (#iSrcId and destination |
|
286 address). |
|
287 |
|
288 @par MIp6Hook::OpenL |
|
289 On entry, this flag is always set and source address is defined. |
|
290 A hook may clear this flag, if it wants the |
|
291 stack choose the source address based on current destination. |
|
292 The clearing operation is normally needed only by a tunneling |
|
293 hook. |
|
294 |
|
295 @note |
|
296 If the hook specifies the source address, it must be either |
|
297 a valid source address for the interface or unspecified |
|
298 address. |
|
299 |
|
300 @par MFlowHook::ReadyL |
|
301 Upon entry to the ReadyL, the source address is always fully |
|
302 known (the hook can assume that #iSrcId and the #ip6 source |
|
303 addresses are valid). |
|
304 If the source address was set before the OpenL, then this |
|
305 must restore the original value (along with the #iSrcId |
|
306 and source address). |
|
307 */ |
|
308 TUint iSourceSet:1; |
|
309 #ifdef TPACKETHEAD_FRAGMENT |
|
310 /** |
|
311 The fragment processing alredy done. |
|
312 |
|
313 This bit is meaningful only in OpenL phase. If already set, |
|
314 then some ealier hook has requested that the packet must |
|
315 be fragmented to fit the mtu. |
|
316 |
|
317 A tunneling hook can set this bit in OpenL, if it needs |
|
318 the fragmenting to happen before the ApplyL is called (e.g. |
|
319 the fragments are tunneled instead of fragmenting the |
|
320 tunneling). |
|
321 |
|
322 This bit can only be set or left as is. It cannot be cleared |
|
323 once set. |
|
324 */ |
|
325 TUint iFragment:1; |
|
326 #endif |
|
327 /** |
|
328 Selector info, the upper layer protocol. |
|
329 |
|
330 iProtocol has the same value as ip6.NextHeader() when iPacket is empty, |
|
331 and otherwise it is the same as NextHeader() of the last extension |
|
332 header in the iPacket. |
|
333 |
|
334 The values of the other selector fields: #iIcmpType, #iIcmpCode |
|
335 #iSrcPort and #iDstPort depend on iProtocol. Whenever iProtocol |
|
336 is changed, the other fields must be updated accordingly. |
|
337 |
|
338 @par MIp6Hook::OpenL |
|
339 Because iPacket cannot be modified during the OpenL phase, the |
|
340 content of this field and the Next Header (protocol) field in |
|
341 the #ip6 pseudoheader must always be the same. This field should |
|
342 be considered as <b>read-only</b>, unless the hook intends to |
|
343 apply IP-in-IP tunneling, in which case the hook <b>must</b> |
|
344 change the value to the appropriate tunneling protocol |
|
345 (#KProtocolInet6Ipip or #KProtocolInetIpip). |
|
346 |
|
347 @par MFlowHook::ReadyL |
|
348 Only a tunneling hook needs to restore the value here to match |
|
349 the original upper layer protocol. See #iPacket for |
|
350 more detailed information. |
|
351 */ |
|
352 TUint8 iProtocol; |
|
353 /** |
|
354 Selector field whose value depends on #iProtocol. |
|
355 |
|
356 If this field does not have meaning with the protocol, |
|
357 the field content should be set to ZERO. |
|
358 */ |
|
359 TUint8 iIcmpType; |
|
360 /** |
|
361 Selector field whose value depends on #iProtocol. |
|
362 |
|
363 If this field does not have meaning with the protocol, |
|
364 the field content should be set to ZERO. |
|
365 */ |
|
366 TUint8 iIcmpCode; |
|
367 /** |
|
368 Selector field whose value depends on #iProtocol. |
|
369 |
|
370 If this field does not have meaning with the protocol, |
|
371 the field content should be set to ZERO. |
|
372 */ |
|
373 TUint16 iSrcPort; |
|
374 /** |
|
375 Selector field whose value depends on #iProtocol. |
|
376 |
|
377 If this field does not have meaning with the protocol, |
|
378 the field content should be set to ZERO. |
|
379 */ |
|
380 TUint16 iDstPort; |
|
381 /** |
|
382 The amount of pre-computed IPv6 extension headers in iPacket which |
|
383 are copied to the beginning of each outgoing packet |
|
384 |
|
385 If iOffset > 0, then #iPacket includes that much of extension |
|
386 headers that are copied in front of each packet. |
|
387 */ |
|
388 TInt iOffset; |
|
389 /** |
|
390 Pre-computed extension headers for all packets in this flow. |
|
391 |
|
392 These can only be added in the ReadyL phase. If any of the |
|
393 ReadyL's adds extension headers into this, it must take care |
|
394 of maintaining the correct Next Header in the virtual IP header |
|
395 (and the original upper layer protocol must be placed in the |
|
396 next header of the last extension header added. |
|
397 |
|
398 Stack copies the content of this to each outgoing packet, just below |
|
399 the IP header, before running the ApplyL functions of the outbound |
|
400 flow hooks. |
|
401 |
|
402 @par MIp6Hook::OpenL |
|
403 The iPacket <b>must not</b> be modified during the OpenL phase. |
|
404 |
|
405 @par MFlowHook::ReadyL |
|
406 A non-tunneling hook may add extension headers into the current |
|
407 iPacket. A tunneling hook has more complex requirements: |
|
408 it must save the current iPacket and #iOffset and initialize |
|
409 iOffset = 0, and iPacket as empty. |
|
410 |
|
411 @par MFlowHook::ApplyL |
|
412 When a tunneling hook adds the tunneling IP header, it |
|
413 must also copy the saved iPacket below the added IP header. |
|
414 */ |
|
415 RMBufPacketPeek iPacket; |
|
416 /** |
|
417 The received packet which caused an ICMP error reply to be sent. |
|
418 |
|
419 This is only used for ICMP error repply flows, and should be |
|
420 ignored by others -- mainly for IPSEC hook. The packet, if |
|
421 present, is in unpacked state. |
|
422 */ |
|
423 RMBufPacketBase iIcmp; |
|
424 /** |
|
425 The current destination interface. |
|
426 |
|
427 This is ONLY used during connect/OpenL phase. |
|
428 |
|
429 The value is maintained by the stack, and is intended as |
|
430 read-only information for the hooks that have a use for |
|
431 it (for example, IPSEC implementing VPN specific policies). |
|
432 |
|
433 A hook must not modify this value (the stack will recompute |
|
434 the value after each OpenL, based on the possibly changed |
|
435 address parameters in the TPacketHead) |
|
436 |
|
437 @par MIp6Hook::OpenL |
|
438 <b>read-only</b> |
|
439 @par MFlowHook::ReadyL |
|
440 <b>read-only</b> |
|
441 */ |
|
442 TUint32 iInterfaceIndex; |
|
443 }; |
|
444 |
106 |
445 class TInet6PacketBase |
107 class TInet6PacketBase |
446 /** |
108 /** |
447 * Thin base class for the TInet6Packet. |
109 * Thin base class for the TInet6Packet. |
448 */ |
110 */ |
591 */ |
253 */ |
592 T *iHdr; |
254 T *iHdr; |
593 }; |
255 }; |
594 |
256 |
595 |
257 |
596 // TPacketPoker |
|
597 // ************ |
|
598 class TPacketPoker |
|
599 /** |
|
600 Provides a utility for linear scanning of a chain of RMBuf objects (an RMBufChain). |
|
601 |
|
602 An object of this type maintains a current point in the RMBufChain. This point |
|
603 can only move forward, and a leave occurs if the point advances beyond the |
|
604 end of the chain. |
|
605 |
|
606 Any pointers and aligns arranged before the current point, remain valid: for |
|
607 example, you can save a reference and advance the pointer, and the reference |
|
608 remains usable. |
|
609 |
|
610 If instead you need to go to a single specified offset, then use |
|
611 RMBufChain::Goto() or RMBufPacketPeek::Access(). |
|
612 |
|
613 @post |
|
614 A Generic implementation assert: |
|
615 after construct, iTail == 0 iff iCurrent == 0 (all scanned), or |
|
616 in other words: as long as there are bytes after current point, |
|
617 iTail will be non-zero (and More() returns ETrue). |
|
618 All methods maintain this invariant or leave, if impossible. |
|
619 |
|
620 Some other utility methods, not directly related to scanning, are also included. |
|
621 @since v7.0 |
|
622 @publishedAll |
|
623 @released |
|
624 */ |
|
625 { |
|
626 public: |
|
627 IMPORT_C TPacketPoker(RMBufChain &aChain); |
|
628 |
|
629 inline void SkipL(TInt aSize) |
|
630 /** |
|
631 Moves the current point forward a specified number of bytes. |
|
632 |
|
633 @param aSize Number of bytes to move forward |
|
634 @leave KErrEof |
|
635 if the request cannot be satisfied. |
|
636 */ |
|
637 { if (aSize < iTail) { iTail -= aSize; iOffset += aSize; } else OverL(aSize); } |
|
638 |
|
639 inline TUint8 *Ptr() const |
|
640 /** |
|
641 Raw pointer to the current point (can be invalid, if iTail = 0). |
|
642 |
|
643 @note Internal "unsafe" method |
|
644 */ |
|
645 {return iCurrent->Ptr() + iOffset; } |
|
646 |
|
647 inline TUint8 *ReferenceL(TInt aSize = 1) |
|
648 /** |
|
649 Gets a pointer to the current point, such that |
|
650 at least the specified minimum number of bytes can be read. |
|
651 |
|
652 @param aSize |
|
653 Specified minimum number of bytes to be read through |
|
654 the returned pointer. |
|
655 @return Raw data pointer |
|
656 @leave KErrEof |
|
657 if the request cannot be satisfied. |
|
658 */ |
|
659 { if (iTail >= aSize) return Ptr(); else return AdjustL(aSize); } |
|
660 |
|
661 inline TUint8 *ReferenceAndSkipL(TInt aSize) |
|
662 /** |
|
663 Gets a pointer to the current point, such that at least the |
|
664 specified minimum number of bytes can be read, |
|
665 and moves the point the specified number of bytes forward. |
|
666 |
|
667 @param aSize |
|
668 Specified minimum number of bytes to be read through the returned |
|
669 pointer, and the number of bytes to move forward |
|
670 @return |
|
671 Raw data pointer |
|
672 @leave KErrEof |
|
673 if the request cannot be satisfied. |
|
674 */ |
|
675 { TUint8 *x = ReferenceL(aSize); SkipL(aSize); return x; } |
|
676 |
|
677 inline TInt Remainder() const |
|
678 /** |
|
679 Gets the length of the contiguous space after the current point. |
|
680 |
|
681 @return Length after the current point |
|
682 */ |
|
683 { return iTail; } |
|
684 |
|
685 inline TBool AtBegin() const |
|
686 /** |
|
687 Tests whether the current point is at the beginning of an RMBuf. |
|
688 |
|
689 @return ETrue if current point is at the beginning |
|
690 */ |
|
691 { return iOffset == 0; } |
|
692 |
|
693 inline TBool More() const |
|
694 /** |
|
695 Tests whether there is more data to scan. |
|
696 |
|
697 @return ETrue if there is more data to scan |
|
698 */ |
|
699 { return iTail > 0; } |
|
700 |
|
701 IMPORT_C static TBool IsExtensionHeader(TInt aProtocolId); |
|
702 private: |
|
703 IMPORT_C void OverL(TInt aSize); |
|
704 IMPORT_C TUint8 *AdjustL(TInt aSize); |
|
705 /** The RMBuf of the current point. */ |
|
706 RMBuf *iCurrent; |
|
707 /** The offset of the current point in the RMBuf. */ |
|
708 TInt iOffset; |
|
709 /** Remaining bytes starting from the current point in the RMBuf. */ |
|
710 TInt iTail; |
|
711 }; |
|
712 |
|
713 #endif |
258 #endif |