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authorRalf Baechle <ralf@linux-mips.org>1997-04-29 21:13:14 +0000
committer <ralf@linux-mips.org>1997-04-29 21:13:14 +0000
commit19c9bba94152148523ba0f7ef7cffe3d45656b11 (patch)
tree40b1cb534496a7f1ca0f5c314a523c69f1fee464 /net/x25/x25_subr.c
parent7206675c40394c78a90e74812bbdbf8cf3cca1be (diff)
Import of Linux/MIPS 2.1.36
Diffstat (limited to 'net/x25/x25_subr.c')
-rw-r--r--net/x25/x25_subr.c386
1 files changed, 386 insertions, 0 deletions
diff --git a/net/x25/x25_subr.c b/net/x25/x25_subr.c
new file mode 100644
index 000000000..245109ee9
--- /dev/null
+++ b/net/x25/x25_subr.c
@@ -0,0 +1,386 @@
+/*
+ * X.25 Packet Layer release 001
+ *
+ * This is ALPHA test software. This code may break your machine, randomly fail to work with new
+ * releases, misbehave and/or generally screw up. It might even work.
+ *
+ * This code REQUIRES 2.1.15 or higher
+ *
+ * This module:
+ * This module 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 (at your option) any later version.
+ *
+ * History
+ * X.25 001 Jonathan Naylor Started coding.
+ */
+
+#include <linux/config.h>
+#if defined(CONFIG_X25) || defined(CONFIG_X25_MODULE)
+#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/inet.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <asm/segment.h>
+#include <asm/system.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <net/x25.h>
+
+/*
+ * This routine purges all of the queues of frames.
+ */
+void x25_clear_queues(struct sock *sk)
+{
+ struct sk_buff *skb;
+
+ while ((skb = skb_dequeue(&sk->write_queue)) != NULL)
+ kfree_skb(skb, FREE_WRITE);
+
+ while ((skb = skb_dequeue(&sk->protinfo.x25->interrupt_in_queue)) != NULL)
+ kfree_skb(skb, FREE_READ);
+
+ while ((skb = skb_dequeue(&sk->protinfo.x25->interrupt_out_queue)) != NULL)
+ kfree_skb(skb, FREE_WRITE);
+
+ while ((skb = skb_dequeue(&sk->protinfo.x25->fragment_queue)) != NULL)
+ kfree_skb(skb, FREE_READ);
+}
+
+/*
+ * Validate that the value of nr is between va and vs. Return true or
+ * false for testing.
+ */
+int x25_validate_nr(struct sock *sk, unsigned short nr)
+{
+ unsigned short vc = sk->protinfo.x25->va;
+ int modulus;
+
+ modulus = (sk->protinfo.x25->neighbour->extended) ? X25_EMODULUS : X25_SMODULUS;
+
+ while (vc != sk->protinfo.x25->vs) {
+ if (nr == vc) return 1;
+ vc = (vc + 1) % modulus;
+ }
+
+ if (nr == sk->protinfo.x25->vs) return 1;
+
+ return 0;
+}
+
+/*
+ * This routine is called when the packet layer internally generates a
+ * control frame.
+ */
+void x25_write_internal(struct sock *sk, int frametype)
+{
+ struct sk_buff *skb;
+ unsigned char *dptr;
+ unsigned char facilities[X25_MAX_FAC_LEN];
+ unsigned char addresses[1 + X25_ADDR_LEN];
+ unsigned char lci1, lci2;
+ int len;
+
+ /*
+ * Default safe frame size.
+ */
+ len = X25_MAX_L2_LEN + X25_EXT_MIN_LEN;
+
+ /*
+ * Adjust frame size.
+ */
+ switch (frametype) {
+ case X25_CALL_REQUEST:
+ len += 1 + X25_ADDR_LEN + X25_MAX_FAC_LEN + X25_MAX_CUD_LEN;
+ break;
+ case X25_CALL_ACCEPTED:
+ len += 1 + X25_MAX_FAC_LEN + X25_MAX_CUD_LEN;
+ break;
+ case X25_CLEAR_REQUEST:
+ case X25_RESET_REQUEST:
+ len += 2;
+ break;
+ case X25_RR:
+ case X25_RNR:
+ case X25_REJ:
+ case X25_CLEAR_CONFIRMATION:
+ case X25_INTERRUPT_CONFIRMATION:
+ case X25_RESET_CONFIRMATION:
+ break;
+ default:
+ printk(KERN_ERR "X.25: invalid frame type %02X\n", frametype);
+ return;
+ }
+
+ if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
+ return;
+
+ /*
+ * Space for Ethernet and 802.2 LLC headers.
+ */
+ skb_reserve(skb, X25_MAX_L2_LEN);
+
+ /*
+ * Make space for the GFI and LCI, and fill them in.
+ */
+ dptr = skb_put(skb, 2);
+
+ lci1 = (sk->protinfo.x25->lci >> 8) & 0x0F;
+ lci2 = (sk->protinfo.x25->lci >> 0) & 0xFF;
+
+ if (sk->protinfo.x25->neighbour->extended) {
+ *dptr++ = lci1 | X25_GFI_EXTSEQ;
+ *dptr++ = lci2;
+ } else {
+ *dptr++ = lci1 | X25_GFI_STDSEQ;
+ *dptr++ = lci2;
+ }
+
+ /*
+ * Now fill in the frame type specific information.
+ */
+ switch (frametype) {
+
+ case X25_CALL_REQUEST:
+ dptr = skb_put(skb, 1);
+ *dptr++ = X25_CALL_REQUEST;
+ len = x25_addr_aton(addresses, &sk->protinfo.x25->dest_addr, &sk->protinfo.x25->source_addr);
+ dptr = skb_put(skb, len);
+ memcpy(dptr, addresses, len);
+ len = x25_create_facilities(facilities, &sk->protinfo.x25->facilities);
+ dptr = skb_put(skb, len);
+ memcpy(dptr, facilities, len);
+ dptr = skb_put(skb, sk->protinfo.x25->calluserdata.cudlength);
+ memcpy(dptr, sk->protinfo.x25->calluserdata.cuddata, sk->protinfo.x25->calluserdata.cudlength);
+ sk->protinfo.x25->calluserdata.cudlength = 0;
+ break;
+
+ case X25_CALL_ACCEPTED:
+ dptr = skb_put(skb, 2);
+ *dptr++ = X25_CALL_ACCEPTED;
+ *dptr++ = 0x00; /* Address lengths */
+ len = x25_create_facilities(facilities, &sk->protinfo.x25->facilities);
+ dptr = skb_put(skb, len);
+ memcpy(dptr, facilities, len);
+ dptr = skb_put(skb, sk->protinfo.x25->calluserdata.cudlength);
+ memcpy(dptr, sk->protinfo.x25->calluserdata.cuddata, sk->protinfo.x25->calluserdata.cudlength);
+ sk->protinfo.x25->calluserdata.cudlength = 0;
+ break;
+
+ case X25_CLEAR_REQUEST:
+ case X25_RESET_REQUEST:
+ dptr = skb_put(skb, 3);
+ *dptr++ = frametype;
+ *dptr++ = 0x00; /* XXX */
+ *dptr++ = 0x00; /* XXX */
+ break;
+
+ case X25_RR:
+ case X25_RNR:
+ case X25_REJ:
+ if (sk->protinfo.x25->neighbour->extended) {
+ dptr = skb_put(skb, 2);
+ *dptr++ = frametype;
+ *dptr++ = (sk->protinfo.x25->vr << 1) & 0xFE;
+ } else {
+ dptr = skb_put(skb, 1);
+ *dptr = frametype;
+ *dptr++ |= (sk->protinfo.x25->vr << 5) & 0xE0;
+ }
+ break;
+
+ case X25_CLEAR_CONFIRMATION:
+ case X25_INTERRUPT_CONFIRMATION:
+ case X25_RESET_CONFIRMATION:
+ dptr = skb_put(skb, 1);
+ *dptr = frametype;
+ break;
+ }
+
+ x25_transmit_link(skb, sk->protinfo.x25->neighbour);
+}
+
+/*
+ * Unpick the contents of the passed X.25 Packet Layer frame.
+ */
+int x25_decode(struct sock *sk, struct sk_buff *skb, int *ns, int *nr, int *q, int *d, int *m)
+{
+ unsigned char *frame;
+
+ frame = skb->data;
+
+ *ns = *nr = *q = *d = *m = 0;
+
+ switch (frame[2]) {
+ case X25_CALL_REQUEST:
+ case X25_CALL_ACCEPTED:
+ case X25_CLEAR_REQUEST:
+ case X25_CLEAR_CONFIRMATION:
+ case X25_INTERRUPT:
+ case X25_INTERRUPT_CONFIRMATION:
+ case X25_RESET_REQUEST:
+ case X25_RESET_CONFIRMATION:
+ case X25_RESTART_REQUEST:
+ case X25_RESTART_CONFIRMATION:
+ case X25_REGISTRATION_REQUEST:
+ case X25_REGISTRATION_CONFIRMATION:
+ case X25_DIAGNOSTIC:
+ return frame[2];
+ }
+
+ if (sk->protinfo.x25->neighbour->extended) {
+ if (frame[2] == X25_RR ||
+ frame[2] == X25_RNR ||
+ frame[2] == X25_REJ) {
+ *nr = (frame[3] >> 1) & 0x7F;
+ return frame[2];
+ }
+ } else {
+ if ((frame[2] & 0x1F) == X25_RR ||
+ (frame[2] & 0x1F) == X25_RNR ||
+ (frame[2] & 0x1F) == X25_REJ) {
+ *nr = (frame[2] >> 5) & 0x07;
+ return frame[2] & 0x1F;
+ }
+ }
+
+ if (sk->protinfo.x25->neighbour->extended) {
+ if ((frame[2] & 0x01) == X25_DATA) {
+ *q = (frame[0] & X25_Q_BIT) == X25_Q_BIT;
+ *d = (frame[0] & X25_D_BIT) == X25_D_BIT;
+ *m = (frame[3] & X25_EXT_M_BIT) == X25_EXT_M_BIT;
+ *nr = (frame[3] >> 1) & 0x7F;
+ *ns = (frame[2] >> 1) & 0x7F;
+ return X25_DATA;
+ }
+ } else {
+ if ((frame[2] & 0x01) == X25_DATA) {
+ *q = (frame[0] & X25_Q_BIT) == X25_Q_BIT;
+ *d = (frame[0] & X25_D_BIT) == X25_D_BIT;
+ *m = (frame[2] & X25_STD_M_BIT) == X25_STD_M_BIT;
+ *nr = (frame[2] >> 5) & 0x07;
+ *ns = (frame[2] >> 1) & 0x07;
+ return X25_DATA;
+ }
+ }
+
+ printk(KERN_DEBUG "X.25: invalid PLP frame %02X %02X %02X\n", frame[0], frame[1], frame[2]);
+
+ return X25_ILLEGAL;
+}
+
+/*
+ * Parse a set of facilities into the facilities structure. Unrecognised
+ * facilities are written to the debug log file.
+ */
+int x25_parse_facilities(struct sk_buff *skb, struct x25_facilities *facilities)
+{
+ unsigned int len;
+ unsigned char *p = skb->data;
+
+ memset(facilities, 0x00, sizeof(struct x25_facilities));
+
+ len = *p++;
+
+ while (len > 0) {
+ switch (*p & X25_FAC_CLASS_MASK) {
+ case X25_FAC_CLASS_A:
+ switch (*p) {
+ case X25_FAC_REVERSE:
+ facilities->reverse = (p[1] & 0x01);
+ break;
+ case X25_FAC_THROUGHPUT:
+ facilities->throughput = p[1];
+ break;
+ default:
+ printk(KERN_DEBUG "X.25: unknown facility %02X, value %02X\n", p[0], p[1]);
+ break;
+ }
+ p += 2;
+ len -= 2;
+ break;
+
+ case X25_FAC_CLASS_B:
+ switch (*p) {
+ case X25_FAC_PACKET_SIZE:
+ facilities->pacsize_in = p[1];
+ facilities->pacsize_out = p[2];
+ break;
+ case X25_FAC_WINDOW_SIZE:
+ facilities->winsize_in = p[1];
+ facilities->winsize_out = p[2];
+ break;
+ default:
+ printk(KERN_DEBUG "X.25: unknown facility %02X, values %02X, %02X\n", p[0], p[1], p[2]);
+ break;
+ }
+ p += 3;
+ len -= 3;
+ break;
+
+ case X25_FAC_CLASS_C:
+ printk(KERN_DEBUG "X.25: unknown facility %02X, values %02X, %02X, %02X\n", p[0], p[1], p[2], p[3]);
+ p += 4;
+ len -= 4;
+ break;
+
+ case X25_FAC_CLASS_D:
+ printk(KERN_DEBUG "X.25: unknown facility %02X, length %d, values %02X, %02X, %02X, %02X\n", p[0], p[1], p[2], p[3], p[4], p[5]);
+ p += p[1] + 2;
+ len -= p[1] + 2;
+ break;
+ }
+ }
+
+ return p - skb->data;
+}
+
+/*
+ * Create a set of facilities.
+ */
+int x25_create_facilities(unsigned char *buffer, struct x25_facilities *facilities)
+{
+ unsigned char *p = buffer + 1;
+ int len;
+
+ if (facilities->reverse != 0) {
+ *p++ = X25_FAC_REVERSE;
+ *p++ = (facilities->reverse) ? 0x01 : 0x00;
+ }
+
+ if (facilities->throughput != 0) {
+ *p++ = X25_FAC_THROUGHPUT;
+ *p++ = facilities->throughput;
+ }
+
+ if (facilities->pacsize_in != 0 || facilities->pacsize_out != 0) {
+ *p++ = X25_FAC_PACKET_SIZE;
+ *p++ = (facilities->pacsize_in == 0) ? facilities->pacsize_out : facilities->pacsize_in;
+ *p++ = (facilities->pacsize_out == 0) ? facilities->pacsize_in : facilities->pacsize_out;
+ }
+
+ if (facilities->winsize_in != 0 || facilities->winsize_out != 0) {
+ *p++ = X25_FAC_WINDOW_SIZE;
+ *p++ = (facilities->winsize_in == 0) ? facilities->winsize_out : facilities->winsize_in;
+ *p++ = (facilities->winsize_out == 0) ? facilities->winsize_in : facilities->winsize_out;
+ }
+
+ len = p - buffer;
+ buffer[0] = len - 1;
+
+ return len;
+}
+
+#endif