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authorRalf Baechle <ralf@linux-mips.org>1999-06-17 14:08:29 +0000
committerRalf Baechle <ralf@linux-mips.org>1999-06-17 14:08:29 +0000
commit57d569635c05dc4ea9b9f1f8dcec69b9ddc989b2 (patch)
tree1f703abf7d95dcd50ee52da3b96eb1b4b2b4ea53 /net/decnet/dn_nsp_in.c
parent59223edaa18759982db0a8aced0e77457d10c68e (diff)
The rest of 2.3.6.
Diffstat (limited to 'net/decnet/dn_nsp_in.c')
-rw-r--r--net/decnet/dn_nsp_in.c703
1 files changed, 703 insertions, 0 deletions
diff --git a/net/decnet/dn_nsp_in.c b/net/decnet/dn_nsp_in.c
new file mode 100644
index 000000000..6d10df045
--- /dev/null
+++ b/net/decnet/dn_nsp_in.c
@@ -0,0 +1,703 @@
+
+/*
+ * DECnet An implementation of the DECnet protocol suite for the LINUX
+ * operating system. DECnet is implemented using the BSD Socket
+ * interface as the means of communication with the user level.
+ *
+ * DECnet Network Services Protocol (Input)
+ *
+ * Author: Eduardo Marcelo Serrat <emserrat@geocities.com>
+ *
+ * Changes:
+ *
+ * Steve Whitehouse: Split into dn_nsp_in.c and dn_nsp_out.c from
+ * original dn_nsp.c.
+ * Steve Whitehouse: Updated to work with my new routing architecture.
+ * Steve Whitehouse: Add changes from Eduardo Serrat's patches.
+ * Steve Whitehouse: Put all ack handling code in a common routine.
+ * Steve Whitehouse: Put other common bits into dn_nsp_rx()
+ * Steve Whitehouse: More checks on skb->len to catch bogus packets
+ * Fixed various race conditions and possible nasties.
+ * Steve Whitehouse: Now handles returned conninit frames.
+ */
+
+/******************************************************************************
+ (c) 1995-1998 E.M. Serrat emserrat@geocities.com
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+*******************************************************************************/
+
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/inet.h>
+#include <linux/route.h>
+#include <net/sock.h>
+#include <asm/segment.h>
+#include <asm/system.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/termios.h>
+#include <linux/interrupt.h>
+#include <linux/proc_fs.h>
+#include <linux/stat.h>
+#include <linux/init.h>
+#include <linux/poll.h>
+#include <net/neighbour.h>
+#include <net/dst.h>
+#include <net/dn_nsp.h>
+#include <net/dn_dev.h>
+#include <net/dn_route.h>
+#include <net/dn_raw.h>
+
+
+/*
+ * For this function we've flipped the cross-subchannel bit
+ * if the message is an otherdata or linkservice message. Thus
+ * we can use it to work out what to update.
+ */
+static void dn_ack(struct sock *sk, struct sk_buff *skb, unsigned short ack)
+{
+ struct dn_scp *scp = &sk->protinfo.dn;
+ unsigned short type = ((ack >> 12) & 0x0003);
+ int wakeup = 0;
+
+ /* printk(KERN_DEBUG "dn_ack: %hd 0x%04hx\n", type, ack); */
+
+ switch(type) {
+ case 0: /* ACK - Data */
+ if (after(ack, scp->ackrcv_dat)) {
+ scp->ackrcv_dat = ack & 0x0fff;
+ wakeup |= dn_nsp_check_xmit_queue(sk, skb, &scp->data_xmit_queue, ack);
+ }
+ break;
+ case 1: /* NAK - Data */
+ break;
+ case 2: /* ACK - OtherData */
+ if (after(ack, scp->ackrcv_oth)) {
+ scp->ackrcv_oth = ack & 0x0fff;
+ wakeup |= dn_nsp_check_xmit_queue(sk, skb, &scp->other_xmit_queue, ack);
+ }
+ break;
+ case 3: /* NAK - OtherData */
+ break;
+ }
+
+ if (wakeup && !sk->dead)
+ sk->state_change(sk);
+}
+
+/*
+ * This function is a universal ack processor.
+ */
+static int dn_process_ack(struct sock *sk, struct sk_buff *skb, int oth)
+{
+ unsigned short *ptr = (unsigned short *)skb->data;
+ int len = 0;
+ unsigned short ack;
+
+ if (skb->len < 2)
+ return len;
+
+ if ((ack = dn_ntohs(*ptr)) & 0x8000) {
+ skb_pull(skb, 2);
+ ptr++;
+ len += 2;
+ if ((ack & 0x4000) == 0) {
+ if (oth)
+ ack ^= 0x2000;
+ dn_ack(sk, skb, ack);
+ }
+ }
+
+ if (skb->len < 2)
+ return len;
+
+ if ((ack = dn_ntohs(*ptr)) & 0x8000) {
+ skb_pull(skb, 2);
+ len += 2;
+ if ((ack & 0x4000) == 0) {
+ if (oth)
+ ack ^= 0x2000;
+ dn_ack(sk, skb, ack);
+ }
+ }
+
+ return len;
+}
+
+
+/*
+ * This function uses a slightly different lookup method
+ * to find its sockets, since it searches on object name/number
+ * rather than port numbers
+ */
+static int dn_conninit_rx(struct sk_buff *skb)
+{
+ struct sock *sk;
+ struct dn_skb_cb *cb = (struct dn_skb_cb *)skb->cb;
+ struct nsp_conn_init_msg *msg = (struct nsp_conn_init_msg *)skb->data;
+ struct sockaddr_dn addr;
+ unsigned char type = 0;
+
+ memset(&addr, 0, sizeof(struct sockaddr_dn));
+
+ cb->src_port = msg->srcaddr;
+ cb->dst_port = msg->dstaddr;
+ cb->services = msg->services;
+ cb->info = msg->info;
+ cb->segsize = dn_ntohs(msg->segsize);
+
+ skb_pull(skb, sizeof(*msg));
+
+ /* printk(KERN_DEBUG "username2sockaddr 1\n"); */
+ if (dn_username2sockaddr(skb->data, skb->len, &addr, &type) < 0)
+ goto free_out;
+
+ if (type > 1)
+ goto free_out;
+
+ /* printk(KERN_DEBUG "looking for listener...\n"); */
+ if ((sk = dn_sklist_find_listener(&addr)) == NULL)
+ return 1;
+
+ /* printk(KERN_DEBUG "checking backlog...\n"); */
+ if (sk->ack_backlog >= sk->max_ack_backlog)
+ goto free_out;
+
+ /* printk(KERN_DEBUG "waking up socket...\n"); */
+ sk->ack_backlog++;
+ skb_queue_tail(&sk->receive_queue, skb);
+ sk->state_change(sk);
+
+ return 0;
+
+free_out:
+ kfree_skb(skb);
+ return 0;
+}
+
+static void dn_nsp_conn_conf(struct sock *sk, struct sk_buff *skb)
+{
+ struct dn_skb_cb *cb = (struct dn_skb_cb *)skb->cb;
+ struct dn_scp *scp = &sk->protinfo.dn;
+
+ if (skb->len < 3)
+ goto out;
+
+ cb->services = *skb->data;
+ cb->info = *(skb->data+1);
+ skb_pull(skb, 2);
+ cb->segsize = dn_ntohs(*(__u16 *)skb->data);
+ skb_pull(skb, 2);
+
+ /*
+ * FIXME: Check out services and info fields to check that
+ * we can talk to this kind of node.
+ */
+
+ if ((scp->state == DN_CI) || (scp->state == DN_CD)) {
+ scp->persist = 0;
+ scp->addrrem = cb->src_port;
+ sk->state = TCP_ESTABLISHED;
+ scp->state = DN_RUN;
+
+ if (scp->mss > cb->segsize)
+ scp->mss = cb->segsize;
+ if (scp->mss < 230)
+ scp->mss = 230;
+
+ if (skb->len > 0) {
+ unsigned char dlen = *skb->data;
+ if ((dlen <= 16) && (dlen <= skb->len)) {
+ scp->conndata_in.opt_optl = dlen;
+ memcpy(scp->conndata_in.opt_data, skb->data + 1, dlen);
+ }
+ }
+ dn_nsp_send_lnk(sk, DN_NOCHANGE);
+ if (!sk->dead)
+ sk->state_change(sk);
+ }
+
+out:
+ kfree_skb(skb);
+}
+
+static void dn_nsp_conn_ack(struct sock *sk, struct sk_buff *skb)
+{
+ struct dn_scp *scp = &sk->protinfo.dn;
+
+ if (scp->state == DN_CI) {
+ scp->state = DN_CD;
+ scp->persist = 0;
+ }
+
+ kfree_skb(skb);
+}
+
+static void dn_nsp_disc_init(struct sock *sk, struct sk_buff *skb)
+{
+ struct dn_scp *scp = &sk->protinfo.dn;
+ struct dn_skb_cb *cb = (struct dn_skb_cb *)skb->cb;
+ unsigned short reason;
+
+ /* printk(KERN_DEBUG "DECnet: discinit %d\n", skb->len); */
+
+ if (skb->len < 2)
+ goto out;
+
+ reason = dn_ntohs(*(__u16 *)skb->data);
+ skb_pull(skb, 2);
+
+ scp->discdata_in.opt_status = reason;
+ scp->discdata_in.opt_optl = 0;
+ memset(scp->discdata_in.opt_data, 0, 16);
+
+ if (skb->len > 0) {
+ unsigned char dlen = *skb->data;
+ if ((dlen <= 16) && (dlen <= skb->len)) {
+ scp->discdata_in.opt_optl = dlen;
+ memcpy(scp->discdata_in.opt_data, skb->data + 1, dlen);
+ }
+ }
+
+ scp->addrrem = cb->src_port;
+ sk->state = TCP_CLOSE;
+
+ /* printk(KERN_DEBUG "DECnet: discinit\n"); */
+
+ switch(scp->state) {
+ case DN_CI:
+ case DN_CD:
+ scp->state = DN_RJ;
+ break;
+ case DN_RUN:
+ sk->shutdown |= SHUTDOWN_MASK;
+ scp->state = DN_DN;
+ break;
+ case DN_DI:
+ scp->state = DN_DIC;
+ break;
+ }
+
+ if (!sk->dead)
+ sk->state_change(sk);
+
+ dn_destroy_sock(sk);
+
+out:
+ kfree_skb(skb);
+}
+
+/*
+ * disc_conf messages are also called no_resources or no_link
+ * messages depending upon the "reason" field.
+ */
+static void dn_nsp_disc_conf(struct sock *sk, struct sk_buff *skb)
+{
+ struct dn_scp *scp = &sk->protinfo.dn;
+ unsigned short reason;
+
+ if (skb->len != 2)
+ goto out;
+
+ reason = dn_ntohs(*(__u16 *)skb->data);
+
+ sk->state = TCP_CLOSE;
+
+ switch(scp->state) {
+ case DN_CI:
+ scp->state = DN_NR;
+ break;
+ case DN_DR:
+ if (reason == NSP_REASON_DC)
+ scp->state = DN_DRC;
+ if (reason == NSP_REASON_NL)
+ scp->state = DN_CN;
+ break;
+ case DN_DI:
+ scp->state = DN_DIC;
+ break;
+ case DN_RUN:
+ sk->shutdown |= SHUTDOWN_MASK;
+ case DN_CC:
+ scp->state = DN_CN;
+ }
+
+ if (!sk->dead)
+ sk->state_change(sk);
+
+ dn_destroy_sock(sk);
+
+out:
+ kfree_skb(skb);
+}
+
+static void dn_nsp_linkservice(struct sock *sk, struct sk_buff *skb)
+{
+ struct dn_skb_cb *cb = (struct dn_skb_cb *)skb->cb;
+ unsigned short segnum;
+ unsigned char lsflags;
+ char fcval;
+
+ if (skb->len != 4)
+ goto out;
+
+ cb->segnum = segnum = dn_ntohs(*(__u16 *)skb->data);
+ skb_pull(skb, 2);
+ lsflags = *(unsigned char *)skb->data;
+ skb_pull(skb, 1);
+ fcval = *(char *)skb->data;
+
+ if (lsflags & 0xf0)
+ goto out;
+
+ if (((sk->protinfo.dn.numoth_rcv + 1) & 0x0FFF) == (segnum & 0x0FFF)) {
+ sk->protinfo.dn.numoth_rcv += 1;
+ switch(lsflags & 0x03) {
+ case 0x00:
+ break;
+ case 0x01:
+ sk->protinfo.dn.flowrem_sw = DN_DONTSEND;
+ break;
+ case 0x02:
+ sk->protinfo.dn.flowrem_sw = DN_SEND;
+ dn_nsp_output(sk);
+ if (!sk->dead)
+ sk->state_change(sk);
+ }
+
+ }
+
+ dn_nsp_send_oth_ack(sk);
+
+out:
+ kfree_skb(skb);
+}
+
+/*
+ * Copy of sock_queue_rcv_skb (from net/core/datagram.c) to
+ * queue other data segments. Also we send SIGURG here instead
+ * of the normal SIGIO, 'cos its out of band data.
+ */
+static __inline__ int dn_queue_other_skb(struct sock *sk, struct sk_buff *skb)
+{
+ struct dn_scp *scp = &sk->protinfo.dn;
+
+ /* Cast skb->rcvbuf to unsigned... It's pointless, but reduces
+ number of warnings when compiling with -W --ANK
+ */
+ if (atomic_read(&sk->rmem_alloc) + skb->truesize >= (unsigned)sk->rcvbuf
+)
+ return -ENOMEM;
+
+#ifdef CONFIG_FILTER
+ if (sk->filter)
+ {
+ if (sk_filter(skb, sk->filter))
+ return -EPERM; /* Toss packet */
+ }
+#endif /* CONFIG_FILTER */
+
+ skb_set_owner_r(skb, sk);
+ skb_queue_tail(&scp->other_receive_queue, skb);
+
+ if (!sk->dead) {
+ struct socket *sock = sk->socket;
+ wake_up_interruptible(sk->sleep);
+ if (!(sock->flags & SO_WAITDATA) && sock->fasync_list)
+ kill_fasync(sock->fasync_list, SIGURG);
+ }
+
+ return 0;
+}
+
+static void dn_nsp_otherdata(struct sock *sk, struct sk_buff *skb)
+{
+ struct dn_scp *scp = &sk->protinfo.dn;
+ unsigned short segnum;
+ struct dn_skb_cb *cb = (struct dn_skb_cb *)skb->cb;
+ int queued = 0;
+
+ if (skb->len < 2)
+ goto out;
+
+ cb->segnum = segnum = dn_ntohs(*(__u16 *)skb->data);
+ skb_pull(skb, 2);
+
+ if (((sk->protinfo.dn.numoth_rcv + 1) & 0x0fff) == (segnum & 0x0fff)) {
+
+ if (dn_queue_other_skb(sk, skb) == 0) {
+ sk->protinfo.dn.numoth_rcv++;
+ scp->other_report = 0;
+ queued = 1;
+ }
+ }
+
+ dn_nsp_send_oth_ack(sk);
+out:
+ if (!queued)
+ kfree_skb(skb);
+}
+
+static void dn_nsp_data(struct sock *sk, struct sk_buff *skb)
+{
+ int queued = 0;
+ unsigned short segnum;
+ struct dn_skb_cb *cb = (struct dn_skb_cb *)skb->cb;
+ struct dn_scp *scp = &sk->protinfo.dn;
+
+ if (skb->len < 2)
+ goto out;
+
+ cb->segnum = segnum = dn_ntohs(*(__u16 *)skb->data);
+ skb_pull(skb, 2);
+
+ if (((sk->protinfo.dn.numdat_rcv + 1) & 0x0FFF) ==
+ (segnum & 0x0FFF)) {
+
+ if (sock_queue_rcv_skb(sk, skb) == 0) {
+ sk->protinfo.dn.numdat_rcv++;
+ queued = 1;
+ }
+
+ if ((scp->flowloc_sw == DN_SEND) && dn_congested(sk)) {
+ scp->flowloc_sw = DN_DONTSEND;
+ dn_nsp_send_lnk(sk, DN_DONTSEND);
+ }
+ }
+
+ dn_nsp_send_data_ack(sk);
+out:
+ if (!queued)
+ kfree_skb(skb);
+}
+
+/*
+ * If one of our conninit messages is returned, this function
+ * deals with it. It puts the socket into the NO_COMMUNICATION
+ * state.
+ */
+static void dn_returned_conninit(struct sk_buff *skb)
+{
+ struct dn_skb_cb *cb = (struct dn_skb_cb *)skb->cb;
+ struct sock *sk;
+
+ cb->dst_port = cb->src_port;
+ cb->src_port = 0;
+
+ if ((sk = dn_find_by_skb(skb)) != NULL) {
+ struct dn_scp *scp = &sk->protinfo.dn;
+ if (scp->state == DN_CI) {
+ scp->state = DN_NC;
+ sk->state = TCP_CLOSE;
+ if (!sk->dead)
+ sk->state_change(sk);
+ }
+ }
+
+ kfree_skb(skb);
+}
+
+int dn_nsp_rx(struct sk_buff *skb)
+{
+ struct dn_skb_cb *cb = (struct dn_skb_cb *)skb->cb;
+ struct sock *sk = NULL;
+ unsigned char *ptr = (unsigned char *)skb->data;
+
+ skb->h.raw = skb->data;
+ cb->nsp_flags = *ptr++;
+
+ if (decnet_debug_level & 1)
+ printk(KERN_DEBUG "dn_nsp_rx: Message type 0x%02x\n", (int)cb->nsp_flags);
+
+#ifdef CONFIG_DECNET_RAW
+ dn_raw_rx_nsp(skb);
+#endif /* CONFIG_DECNET_RAW */
+
+ if (skb->len < 2)
+ goto free_out;
+
+ if (cb->nsp_flags & 0x83)
+ goto free_out;
+
+ /*
+ * Returned packets...
+ */
+ if (cb->rt_flags & DN_RT_F_RTS) {
+ if ((cb->nsp_flags & 0x0c) == 0x08) {
+ switch(cb->nsp_flags & 0x70) {
+ case 0x10:
+ case 0x60:
+ dn_returned_conninit(skb);
+ goto out;
+ }
+ }
+ goto free_out;
+ }
+
+ /*
+ * Filter out conninits and useless packet types
+ */
+ if ((cb->nsp_flags & 0x0c) == 0x08) {
+ switch(cb->nsp_flags & 0x70) {
+ case 0x00: /* NOP */
+ case 0x70: /* Reserved */
+ case 0x50: /* Reserved, Phase II node init */
+ goto free_out;
+ case 0x10:
+ case 0x60:
+ return dn_conninit_rx(skb);
+ }
+ }
+
+ if (skb->len < 3)
+ goto free_out;
+
+ /*
+ * Grab the destination address.
+ */
+ cb->dst_port = *(unsigned short *)ptr;
+ cb->src_port = 0;
+ ptr += 2;
+
+ /*
+ * If not a connack, grab the source address too.
+ */
+ if (skb->len >= 5) {
+ cb->src_port = *(unsigned short *)ptr;
+ ptr += 2;
+ skb_pull(skb, 5);
+ }
+
+ /*
+ * Find the socket to which this skb is destined.
+ */
+ if ((sk = dn_find_by_skb(skb)) != NULL) {
+ struct dn_scp *scp = &sk->protinfo.dn;
+ int ret;
+ /* printk(KERN_DEBUG "dn_nsp_rx: Found a socket\n"); */
+
+ /* Reset backoff */
+ scp->nsp_rxtshift = 0;
+
+ bh_lock_sock(sk);
+ ret = 0;
+ if (sk->lock.users == 0)
+ ret = dn_nsp_backlog_rcv(sk, skb);
+ else
+ sk_add_backlog(sk, skb);
+ bh_unlock_sock(sk);
+
+ return ret;
+ }
+ return 1;
+
+free_out:
+ kfree_skb(skb);
+out:
+ return 0;
+}
+
+/*
+ * This is the main receive routine for sockets. It is called
+ * from the above when the socket is not busy, and also from
+ * sock_release() when there is a backlog queued up.
+ */
+int dn_nsp_backlog_rcv(struct sock *sk, struct sk_buff *skb)
+{
+ struct dn_scp *scp = &sk->protinfo.dn;
+ struct dn_skb_cb *cb = (struct dn_skb_cb *)skb->cb;
+
+ /*
+ * Control packet.
+ */
+ if ((cb->nsp_flags & 0x0c) == 0x08) {
+ /* printk(KERN_DEBUG "control type\n"); */
+ switch(cb->nsp_flags & 0x70) {
+ case 0x20:
+ dn_nsp_conn_conf(sk, skb);
+ break;
+ case 0x30:
+ dn_nsp_disc_init(sk, skb);
+ break;
+ case 0x40:
+ dn_nsp_disc_conf(sk, skb);
+ break;
+ }
+
+ } else if (cb->nsp_flags == 0x24) {
+ /*
+ * Special for connacks, 'cos they don't have
+ * ack data or ack otherdata info.
+ */
+ dn_nsp_conn_ack(sk, skb);
+ } else {
+ int other = 1;
+
+ if ((cb->nsp_flags & 0x1c) == 0)
+ other = 0;
+ if (cb->nsp_flags == 0x04)
+ other = 0;
+
+ /*
+ * Read out ack data here, this applies equally
+ * to data, other data, link serivce and both
+ * ack data and ack otherdata.
+ */
+ dn_process_ack(sk, skb, other);
+
+ /*
+ * If we've some sort of data here then call a
+ * suitable routine for dealing with it, otherwise
+ * the packet is an ack and can be discarded. All
+ * data frames can also kick a CC socket into RUN.
+ */
+ if ((cb->nsp_flags & 0x0c) == 0) {
+
+ if ((scp->state == DN_CC) && !sk->dead) {
+ scp->state = DN_RUN;
+ sk->state = TCP_ESTABLISHED;
+ sk->state_change(sk);
+ }
+
+ if (scp->state != DN_RUN)
+ goto free_out;
+
+ switch(cb->nsp_flags) {
+ case 0x10: /* LS */
+ dn_nsp_linkservice(sk, skb);
+ break;
+ case 0x30: /* OD */
+ dn_nsp_otherdata(sk, skb);
+ break;
+ default:
+ dn_nsp_data(sk, skb);
+ }
+
+ } else { /* Ack, chuck it out here */
+free_out:
+ kfree_skb(skb);
+ }
+ }
+
+ return 0;
+}
+