]>
git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - net/decnet/dn_nsp_in.c
2 * DECnet An implementation of the DECnet protocol suite for the LINUX
3 * operating system. DECnet is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
6 * DECnet Network Services Protocol (Input)
8 * Author: Eduardo Marcelo Serrat <emserrat@geocities.com>
12 * Steve Whitehouse: Split into dn_nsp_in.c and dn_nsp_out.c from
14 * Steve Whitehouse: Updated to work with my new routing architecture.
15 * Steve Whitehouse: Add changes from Eduardo Serrat's patches.
16 * Steve Whitehouse: Put all ack handling code in a common routine.
17 * Steve Whitehouse: Put other common bits into dn_nsp_rx()
18 * Steve Whitehouse: More checks on skb->len to catch bogus packets
19 * Fixed various race conditions and possible nasties.
20 * Steve Whitehouse: Now handles returned conninit frames.
21 * David S. Miller: New socket locking
22 * Steve Whitehouse: Fixed lockup when socket filtering was enabled.
23 * Paul Koning: Fix to push CC sockets into RUN when acks are
26 * Patrick Caulfield: Checking conninits for correctness & sending of error
28 * Steve Whitehouse: Added backlog congestion level return codes.
30 * Steve Whitehouse: Added flow control support (outbound)
31 * Steve Whitehouse: Prepare for nonlinear skbs
34 /******************************************************************************
35 (c) 1995-1998 E.M. Serrat emserrat@geocities.com
37 This program is free software; you can redistribute it and/or modify
38 it under the terms of the GNU General Public License as published by
39 the Free Software Foundation; either version 2 of the License, or
42 This program is distributed in the hope that it will be useful,
43 but WITHOUT ANY WARRANTY; without even the implied warranty of
44 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
45 GNU General Public License for more details.
46 *******************************************************************************/
48 #include <linux/errno.h>
49 #include <linux/types.h>
50 #include <linux/socket.h>
52 #include <linux/kernel.h>
53 #include <linux/timer.h>
54 #include <linux/string.h>
55 #include <linux/sockios.h>
56 #include <linux/net.h>
57 #include <linux/netdevice.h>
58 #include <linux/inet.h>
59 #include <linux/route.h>
60 #include <linux/slab.h>
62 #include <net/tcp_states.h>
63 #include <asm/system.h>
64 #include <linux/fcntl.h>
66 #include <linux/termios.h>
67 #include <linux/interrupt.h>
68 #include <linux/proc_fs.h>
69 #include <linux/stat.h>
70 #include <linux/init.h>
71 #include <linux/poll.h>
72 #include <linux/netfilter_decnet.h>
73 #include <net/neighbour.h>
76 #include <net/dn_nsp.h>
77 #include <net/dn_dev.h>
78 #include <net/dn_route.h>
80 extern int decnet_log_martians
;
82 static void dn_log_martian(struct sk_buff
*skb
, const char *msg
)
84 if (decnet_log_martians
&& net_ratelimit()) {
85 char *devname
= skb
->dev
? skb
->dev
->name
: "???";
86 struct dn_skb_cb
*cb
= DN_SKB_CB(skb
);
87 printk(KERN_INFO
"DECnet: Martian packet (%s) dev=%s src=0x%04hx dst=0x%04hx srcport=0x%04hx dstport=0x%04hx\n",
88 msg
, devname
, le16_to_cpu(cb
->src
), le16_to_cpu(cb
->dst
),
89 le16_to_cpu(cb
->src_port
), le16_to_cpu(cb
->dst_port
));
94 * For this function we've flipped the cross-subchannel bit
95 * if the message is an otherdata or linkservice message. Thus
96 * we can use it to work out what to update.
98 static void dn_ack(struct sock
*sk
, struct sk_buff
*skb
, unsigned short ack
)
100 struct dn_scp
*scp
= DN_SK(sk
);
101 unsigned short type
= ((ack
>> 12) & 0x0003);
105 case 0: /* ACK - Data */
106 if (dn_after(ack
, scp
->ackrcv_dat
)) {
107 scp
->ackrcv_dat
= ack
& 0x0fff;
108 wakeup
|= dn_nsp_check_xmit_queue(sk
, skb
, &scp
->data_xmit_queue
, ack
);
111 case 1: /* NAK - Data */
113 case 2: /* ACK - OtherData */
114 if (dn_after(ack
, scp
->ackrcv_oth
)) {
115 scp
->ackrcv_oth
= ack
& 0x0fff;
116 wakeup
|= dn_nsp_check_xmit_queue(sk
, skb
, &scp
->other_xmit_queue
, ack
);
119 case 3: /* NAK - OtherData */
123 if (wakeup
&& !sock_flag(sk
, SOCK_DEAD
))
124 sk
->sk_state_change(sk
);
128 * This function is a universal ack processor.
130 static int dn_process_ack(struct sock
*sk
, struct sk_buff
*skb
, int oth
)
132 __le16
*ptr
= (__le16
*)skb
->data
;
139 if ((ack
= le16_to_cpu(*ptr
)) & 0x8000) {
143 if ((ack
& 0x4000) == 0) {
146 dn_ack(sk
, skb
, ack
);
153 if ((ack
= le16_to_cpu(*ptr
)) & 0x8000) {
156 if ((ack
& 0x4000) == 0) {
159 dn_ack(sk
, skb
, ack
);
168 * dn_check_idf - Check an image data field format is correct.
169 * @pptr: Pointer to pointer to image data
170 * @len: Pointer to length of image data
171 * @max: The maximum allowed length of the data in the image data field
172 * @follow_on: Check that this many bytes exist beyond the end of the image data
174 * Returns: 0 if ok, -1 on error
176 static inline int dn_check_idf(unsigned char **pptr
, int *len
, unsigned char max
, unsigned char follow_on
)
178 unsigned char *ptr
= *pptr
;
179 unsigned char flen
= *ptr
++;
184 if ((flen
+ follow_on
) > *len
)
193 * Table of reason codes to pass back to node which sent us a badly
194 * formed message, plus text messages for the log. A zero entry in
195 * the reason field means "don't reply" otherwise a disc init is sent with
196 * the specified reason code.
199 unsigned short reason
;
202 { 0, "CI: Truncated message" },
203 { NSP_REASON_ID
, "CI: Destination username error" },
204 { NSP_REASON_ID
, "CI: Destination username type" },
205 { NSP_REASON_US
, "CI: Source username error" },
206 { 0, "CI: Truncated at menuver" },
207 { 0, "CI: Truncated before access or user data" },
208 { NSP_REASON_IO
, "CI: Access data format error" },
209 { NSP_REASON_IO
, "CI: User data format error" }
213 * This function uses a slightly different lookup method
214 * to find its sockets, since it searches on object name/number
215 * rather than port numbers. Various tests are done to ensure that
216 * the incoming data is in the correct format before it is queued to
219 static struct sock
*dn_find_listener(struct sk_buff
*skb
, unsigned short *reason
)
221 struct dn_skb_cb
*cb
= DN_SKB_CB(skb
);
222 struct nsp_conn_init_msg
*msg
= (struct nsp_conn_init_msg
*)skb
->data
;
223 struct sockaddr_dn dstaddr
;
224 struct sockaddr_dn srcaddr
;
225 unsigned char type
= 0;
231 unsigned char menuver
;
233 memset(&dstaddr
, 0, sizeof(struct sockaddr_dn
));
234 memset(&srcaddr
, 0, sizeof(struct sockaddr_dn
));
237 * 1. Decode & remove message header
239 cb
->src_port
= msg
->srcaddr
;
240 cb
->dst_port
= msg
->dstaddr
;
241 cb
->services
= msg
->services
;
242 cb
->info
= msg
->info
;
243 cb
->segsize
= le16_to_cpu(msg
->segsize
);
245 if (!pskb_may_pull(skb
, sizeof(*msg
)))
248 skb_pull(skb
, sizeof(*msg
));
254 * 2. Check destination end username format
256 dstlen
= dn_username2sockaddr(ptr
, len
, &dstaddr
, &type
);
269 * 3. Check source end username format
271 srclen
= dn_username2sockaddr(ptr
, len
, &srcaddr
, &type
);
287 * 4. Check that optional data actually exists if menuver says it does
290 if ((menuver
& (DN_MENUVER_ACC
| DN_MENUVER_USR
)) && (len
< 1))
294 * 5. Check optional access data format
297 if (menuver
& DN_MENUVER_ACC
) {
298 if (dn_check_idf(&ptr
, &len
, 39, 1))
300 if (dn_check_idf(&ptr
, &len
, 39, 1))
302 if (dn_check_idf(&ptr
, &len
, 39, (menuver
& DN_MENUVER_USR
) ? 1 : 0))
307 * 6. Check optional user data format
310 if (menuver
& DN_MENUVER_USR
) {
311 if (dn_check_idf(&ptr
, &len
, 16, 0))
316 * 7. Look up socket based on destination end username
318 return dn_sklist_find_listener(&dstaddr
);
320 dn_log_martian(skb
, ci_err_table
[err
].text
);
321 *reason
= ci_err_table
[err
].reason
;
326 static void dn_nsp_conn_init(struct sock
*sk
, struct sk_buff
*skb
)
328 if (sk_acceptq_is_full(sk
)) {
333 sk
->sk_ack_backlog
++;
334 skb_queue_tail(&sk
->sk_receive_queue
, skb
);
335 sk
->sk_state_change(sk
);
338 static void dn_nsp_conn_conf(struct sock
*sk
, struct sk_buff
*skb
)
340 struct dn_skb_cb
*cb
= DN_SKB_CB(skb
);
341 struct dn_scp
*scp
= DN_SK(sk
);
348 cb
->services
= *ptr
++;
350 cb
->segsize
= le16_to_cpu(*(__le16
*)ptr
);
352 if ((scp
->state
== DN_CI
) || (scp
->state
== DN_CD
)) {
354 scp
->addrrem
= cb
->src_port
;
355 sk
->sk_state
= TCP_ESTABLISHED
;
357 scp
->services_rem
= cb
->services
;
358 scp
->info_rem
= cb
->info
;
359 scp
->segsize_rem
= cb
->segsize
;
361 if ((scp
->services_rem
& NSP_FC_MASK
) == NSP_FC_NONE
)
362 scp
->max_window
= decnet_no_fc_max_cwnd
;
365 u16 dlen
= *skb
->data
;
366 if ((dlen
<= 16) && (dlen
<= skb
->len
)) {
367 scp
->conndata_in
.opt_optl
= cpu_to_le16(dlen
);
368 skb_copy_from_linear_data_offset(skb
, 1,
369 scp
->conndata_in
.opt_data
, dlen
);
372 dn_nsp_send_link(sk
, DN_NOCHANGE
, 0);
373 if (!sock_flag(sk
, SOCK_DEAD
))
374 sk
->sk_state_change(sk
);
381 static void dn_nsp_conn_ack(struct sock
*sk
, struct sk_buff
*skb
)
383 struct dn_scp
*scp
= DN_SK(sk
);
385 if (scp
->state
== DN_CI
) {
393 static void dn_nsp_disc_init(struct sock
*sk
, struct sk_buff
*skb
)
395 struct dn_scp
*scp
= DN_SK(sk
);
396 struct dn_skb_cb
*cb
= DN_SKB_CB(skb
);
397 unsigned short reason
;
402 reason
= le16_to_cpu(*(__le16
*)skb
->data
);
405 scp
->discdata_in
.opt_status
= cpu_to_le16(reason
);
406 scp
->discdata_in
.opt_optl
= 0;
407 memset(scp
->discdata_in
.opt_data
, 0, 16);
410 u16 dlen
= *skb
->data
;
411 if ((dlen
<= 16) && (dlen
<= skb
->len
)) {
412 scp
->discdata_in
.opt_optl
= cpu_to_le16(dlen
);
413 skb_copy_from_linear_data_offset(skb
, 1, scp
->discdata_in
.opt_data
, dlen
);
417 scp
->addrrem
= cb
->src_port
;
418 sk
->sk_state
= TCP_CLOSE
;
424 sk
->sk_err
= ECONNREFUSED
;
427 sk
->sk_shutdown
|= SHUTDOWN_MASK
;
435 if (!sock_flag(sk
, SOCK_DEAD
)) {
436 if (sk
->sk_socket
->state
!= SS_UNCONNECTED
)
437 sk
->sk_socket
->state
= SS_DISCONNECTING
;
438 sk
->sk_state_change(sk
);
442 * It appears that its possible for remote machines to send disc
443 * init messages with no port identifier if we are in the CI and
444 * possibly also the CD state. Obviously we shouldn't reply with
445 * a message if we don't know what the end point is.
448 dn_nsp_send_disc(sk
, NSP_DISCCONF
, NSP_REASON_DC
, GFP_ATOMIC
);
450 scp
->persist_fxn
= dn_destroy_timer
;
451 scp
->persist
= dn_nsp_persist(sk
);
458 * disc_conf messages are also called no_resources or no_link
459 * messages depending upon the "reason" field.
461 static void dn_nsp_disc_conf(struct sock
*sk
, struct sk_buff
*skb
)
463 struct dn_scp
*scp
= DN_SK(sk
);
464 unsigned short reason
;
469 reason
= le16_to_cpu(*(__le16
*)skb
->data
);
471 sk
->sk_state
= TCP_CLOSE
;
478 if (reason
== NSP_REASON_DC
)
480 if (reason
== NSP_REASON_NL
)
487 sk
->sk_shutdown
|= SHUTDOWN_MASK
;
492 if (!sock_flag(sk
, SOCK_DEAD
)) {
493 if (sk
->sk_socket
->state
!= SS_UNCONNECTED
)
494 sk
->sk_socket
->state
= SS_DISCONNECTING
;
495 sk
->sk_state_change(sk
);
498 scp
->persist_fxn
= dn_destroy_timer
;
499 scp
->persist
= dn_nsp_persist(sk
);
505 static void dn_nsp_linkservice(struct sock
*sk
, struct sk_buff
*skb
)
507 struct dn_scp
*scp
= DN_SK(sk
);
508 unsigned short segnum
;
509 unsigned char lsflags
;
512 char *ptr
= skb
->data
;
513 unsigned char fctype
= scp
->services_rem
& NSP_FC_MASK
;
518 segnum
= le16_to_cpu(*(__le16
*)ptr
);
520 lsflags
= *(unsigned char *)ptr
++;
524 * Here we ignore erronous packets which should really
525 * should cause a connection abort. It is not critical
531 if (seq_next(scp
->numoth_rcv
, segnum
)) {
532 seq_add(&scp
->numoth_rcv
, 1);
533 switch(lsflags
& 0x04) { /* FCVAL INT */
534 case 0x00: /* Normal Request */
535 switch(lsflags
& 0x03) { /* FCVAL MOD */
536 case 0x00: /* Request count */
538 unsigned char p_fcval
= -fcval
;
539 if ((scp
->flowrem_dat
> p_fcval
) &&
540 (fctype
== NSP_FC_SCMC
)) {
541 scp
->flowrem_dat
-= p_fcval
;
543 } else if (fcval
> 0) {
544 scp
->flowrem_dat
+= fcval
;
548 case 0x01: /* Stop outgoing data */
549 scp
->flowrem_sw
= DN_DONTSEND
;
551 case 0x02: /* Ok to start again */
552 scp
->flowrem_sw
= DN_SEND
;
557 case 0x04: /* Interrupt Request */
559 scp
->flowrem_oth
+= fcval
;
564 if (wake_up
&& !sock_flag(sk
, SOCK_DEAD
))
565 sk
->sk_state_change(sk
);
568 dn_nsp_send_oth_ack(sk
);
575 * Copy of sock_queue_rcv_skb (from sock.h) without
576 * bh_lock_sock() (its already held when this is called) which
577 * also allows data and other data to be queued to a socket.
579 static __inline__
int dn_queue_skb(struct sock
*sk
, struct sk_buff
*skb
, int sig
, struct sk_buff_head
*queue
)
584 /* Cast skb->rcvbuf to unsigned... It's pointless, but reduces
585 number of warnings when compiling with -W --ANK
587 if (atomic_read(&sk
->sk_rmem_alloc
) + skb
->truesize
>=
588 (unsigned)sk
->sk_rcvbuf
) {
593 err
= sk_filter(sk
, skb
);
598 skb_set_owner_r(skb
, sk
);
599 skb_queue_tail(queue
, skb
);
601 if (!sock_flag(sk
, SOCK_DEAD
))
602 sk
->sk_data_ready(sk
, skb_len
);
607 static void dn_nsp_otherdata(struct sock
*sk
, struct sk_buff
*skb
)
609 struct dn_scp
*scp
= DN_SK(sk
);
610 unsigned short segnum
;
611 struct dn_skb_cb
*cb
= DN_SKB_CB(skb
);
617 cb
->segnum
= segnum
= le16_to_cpu(*(__le16
*)skb
->data
);
620 if (seq_next(scp
->numoth_rcv
, segnum
)) {
622 if (dn_queue_skb(sk
, skb
, SIGURG
, &scp
->other_receive_queue
) == 0) {
623 seq_add(&scp
->numoth_rcv
, 1);
624 scp
->other_report
= 0;
629 dn_nsp_send_oth_ack(sk
);
635 static void dn_nsp_data(struct sock
*sk
, struct sk_buff
*skb
)
638 unsigned short segnum
;
639 struct dn_skb_cb
*cb
= DN_SKB_CB(skb
);
640 struct dn_scp
*scp
= DN_SK(sk
);
645 cb
->segnum
= segnum
= le16_to_cpu(*(__le16
*)skb
->data
);
648 if (seq_next(scp
->numdat_rcv
, segnum
)) {
649 if (dn_queue_skb(sk
, skb
, SIGIO
, &sk
->sk_receive_queue
) == 0) {
650 seq_add(&scp
->numdat_rcv
, 1);
654 if ((scp
->flowloc_sw
== DN_SEND
) && dn_congested(sk
)) {
655 scp
->flowloc_sw
= DN_DONTSEND
;
656 dn_nsp_send_link(sk
, DN_DONTSEND
, 0);
660 dn_nsp_send_data_ack(sk
);
667 * If one of our conninit messages is returned, this function
668 * deals with it. It puts the socket into the NO_COMMUNICATION
671 static void dn_returned_conn_init(struct sock
*sk
, struct sk_buff
*skb
)
673 struct dn_scp
*scp
= DN_SK(sk
);
675 if (scp
->state
== DN_CI
) {
677 sk
->sk_state
= TCP_CLOSE
;
678 if (!sock_flag(sk
, SOCK_DEAD
))
679 sk
->sk_state_change(sk
);
685 static int dn_nsp_no_socket(struct sk_buff
*skb
, unsigned short reason
)
687 struct dn_skb_cb
*cb
= DN_SKB_CB(skb
);
688 int ret
= NET_RX_DROP
;
690 /* Must not reply to returned packets */
691 if (cb
->rt_flags
& DN_RT_F_RTS
)
694 if ((reason
!= NSP_REASON_OK
) && ((cb
->nsp_flags
& 0x0c) == 0x08)) {
695 switch(cb
->nsp_flags
& 0x70) {
697 case 0x60: /* (Retransmitted) Connect Init */
698 dn_nsp_return_disc(skb
, NSP_DISCINIT
, reason
);
699 ret
= NET_RX_SUCCESS
;
701 case 0x20: /* Connect Confirm */
702 dn_nsp_return_disc(skb
, NSP_DISCCONF
, reason
);
703 ret
= NET_RX_SUCCESS
;
713 static int dn_nsp_rx_packet(struct sk_buff
*skb
)
715 struct dn_skb_cb
*cb
= DN_SKB_CB(skb
);
716 struct sock
*sk
= NULL
;
717 unsigned char *ptr
= (unsigned char *)skb
->data
;
718 unsigned short reason
= NSP_REASON_NL
;
720 if (!pskb_may_pull(skb
, 2))
723 skb_reset_transport_header(skb
);
724 cb
->nsp_flags
= *ptr
++;
726 if (decnet_debug_level
& 2)
727 printk(KERN_DEBUG
"dn_nsp_rx: Message type 0x%02x\n", (int)cb
->nsp_flags
);
729 if (cb
->nsp_flags
& 0x83)
733 * Filter out conninits and useless packet types
735 if ((cb
->nsp_flags
& 0x0c) == 0x08) {
736 switch(cb
->nsp_flags
& 0x70) {
738 case 0x70: /* Reserved */
739 case 0x50: /* Reserved, Phase II node init */
743 if (unlikely(cb
->rt_flags
& DN_RT_F_RTS
))
745 sk
= dn_find_listener(skb
, &reason
);
750 if (!pskb_may_pull(skb
, 3))
754 * Grab the destination address.
756 cb
->dst_port
= *(__le16
*)ptr
;
761 * If not a connack, grab the source address too.
763 if (pskb_may_pull(skb
, 5)) {
764 cb
->src_port
= *(__le16
*)ptr
;
770 * Returned packets...
771 * Swap src & dst and look up in the normal way.
773 if (unlikely(cb
->rt_flags
& DN_RT_F_RTS
)) {
774 __le16 tmp
= cb
->dst_port
;
775 cb
->dst_port
= cb
->src_port
;
783 * Find the socket to which this skb is destined.
785 sk
= dn_find_by_skb(skb
);
788 struct dn_scp
*scp
= DN_SK(sk
);
791 scp
->nsp_rxtshift
= 0;
794 * We linearize everything except data segments here.
796 if (cb
->nsp_flags
& ~0x60) {
797 if (unlikely(skb_linearize(skb
)))
801 return sk_receive_skb(sk
, skb
, 0);
804 return dn_nsp_no_socket(skb
, reason
);
811 int dn_nsp_rx(struct sk_buff
*skb
)
813 return NF_HOOK(NFPROTO_DECNET
, NF_DN_LOCAL_IN
, skb
, skb
->dev
, NULL
,
818 * This is the main receive routine for sockets. It is called
819 * from the above when the socket is not busy, and also from
820 * sock_release() when there is a backlog queued up.
822 int dn_nsp_backlog_rcv(struct sock
*sk
, struct sk_buff
*skb
)
824 struct dn_scp
*scp
= DN_SK(sk
);
825 struct dn_skb_cb
*cb
= DN_SKB_CB(skb
);
827 if (cb
->rt_flags
& DN_RT_F_RTS
) {
828 if (cb
->nsp_flags
== 0x18 || cb
->nsp_flags
== 0x68)
829 dn_returned_conn_init(sk
, skb
);
832 return NET_RX_SUCCESS
;
838 if ((cb
->nsp_flags
& 0x0c) == 0x08) {
839 switch(cb
->nsp_flags
& 0x70) {
842 dn_nsp_conn_init(sk
, skb
);
845 dn_nsp_conn_conf(sk
, skb
);
848 dn_nsp_disc_init(sk
, skb
);
851 dn_nsp_disc_conf(sk
, skb
);
855 } else if (cb
->nsp_flags
== 0x24) {
857 * Special for connacks, 'cos they don't have
858 * ack data or ack otherdata info.
860 dn_nsp_conn_ack(sk
, skb
);
864 /* both data and ack frames can kick a CC socket into RUN */
865 if ((scp
->state
== DN_CC
) && !sock_flag(sk
, SOCK_DEAD
)) {
867 sk
->sk_state
= TCP_ESTABLISHED
;
868 sk
->sk_state_change(sk
);
871 if ((cb
->nsp_flags
& 0x1c) == 0)
873 if (cb
->nsp_flags
== 0x04)
877 * Read out ack data here, this applies equally
878 * to data, other data, link serivce and both
879 * ack data and ack otherdata.
881 dn_process_ack(sk
, skb
, other
);
884 * If we've some sort of data here then call a
885 * suitable routine for dealing with it, otherwise
886 * the packet is an ack and can be discarded.
888 if ((cb
->nsp_flags
& 0x0c) == 0) {
890 if (scp
->state
!= DN_RUN
)
893 switch(cb
->nsp_flags
) {
895 dn_nsp_linkservice(sk
, skb
);
898 dn_nsp_otherdata(sk
, skb
);
901 dn_nsp_data(sk
, skb
);
904 } else { /* Ack, chuck it out here */
910 return NET_RX_SUCCESS
;