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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /net/rose/rose_subr.c
Initial import
Diffstat (limited to 'net/rose/rose_subr.c')
-rw-r--r--net/rose/rose_subr.c556
1 files changed, 556 insertions, 0 deletions
diff --git a/net/rose/rose_subr.c b/net/rose/rose_subr.c
new file mode 100644
index 000000000..7ca57741b
--- /dev/null
+++ b/net/rose/rose_subr.c
@@ -0,0 +1,556 @@
+/*
+ * 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
+ * (at your option) any later version.
+ *
+ * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
+ */
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/kernel.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/slab.h>
+#include <net/ax25.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/tcp_states.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <net/rose.h>
+
+static int rose_create_facilities(unsigned char *buffer, struct rose_sock *rose);
+
+/*
+ * This routine purges all of the queues of frames.
+ */
+void rose_clear_queues(struct sock *sk)
+{
+ skb_queue_purge(&sk->sk_write_queue);
+ skb_queue_purge(&rose_sk(sk)->ack_queue);
+}
+
+/*
+ * This routine purges the input queue of those frames that have been
+ * acknowledged. This replaces the boxes labelled "V(a) <- N(r)" on the
+ * SDL diagram.
+ */
+void rose_frames_acked(struct sock *sk, unsigned short nr)
+{
+ struct sk_buff *skb;
+ struct rose_sock *rose = rose_sk(sk);
+
+ /*
+ * Remove all the ack-ed frames from the ack queue.
+ */
+ if (rose->va != nr) {
+ while (skb_peek(&rose->ack_queue) != NULL && rose->va != nr) {
+ skb = skb_dequeue(&rose->ack_queue);
+ kfree_skb(skb);
+ rose->va = (rose->va + 1) % ROSE_MODULUS;
+ }
+ }
+}
+
+void rose_requeue_frames(struct sock *sk)
+{
+ struct sk_buff *skb, *skb_prev = NULL;
+
+ /*
+ * Requeue all the un-ack-ed frames on the output queue to be picked
+ * up by rose_kick. This arrangement handles the possibility of an
+ * empty output queue.
+ */
+ while ((skb = skb_dequeue(&rose_sk(sk)->ack_queue)) != NULL) {
+ if (skb_prev == NULL)
+ skb_queue_head(&sk->sk_write_queue, skb);
+ else
+ skb_append(skb_prev, skb, &sk->sk_write_queue);
+ skb_prev = skb;
+ }
+}
+
+/*
+ * Validate that the value of nr is between va and vs. Return true or
+ * false for testing.
+ */
+int rose_validate_nr(struct sock *sk, unsigned short nr)
+{
+ struct rose_sock *rose = rose_sk(sk);
+ unsigned short vc = rose->va;
+
+ while (vc != rose->vs) {
+ if (nr == vc) return 1;
+ vc = (vc + 1) % ROSE_MODULUS;
+ }
+
+ return nr == rose->vs;
+}
+
+/*
+ * This routine is called when the packet layer internally generates a
+ * control frame.
+ */
+void rose_write_internal(struct sock *sk, int frametype)
+{
+ struct rose_sock *rose = rose_sk(sk);
+ struct sk_buff *skb;
+ unsigned char *dptr;
+ unsigned char lci1, lci2;
+ char buffer[100];
+ int len, faclen = 0;
+
+ len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 1;
+
+ switch (frametype) {
+ case ROSE_CALL_REQUEST:
+ len += 1 + ROSE_ADDR_LEN + ROSE_ADDR_LEN;
+ faclen = rose_create_facilities(buffer, rose);
+ len += faclen;
+ break;
+ case ROSE_CALL_ACCEPTED:
+ case ROSE_CLEAR_REQUEST:
+ case ROSE_RESET_REQUEST:
+ len += 2;
+ break;
+ }
+
+ if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
+ return;
+
+ /*
+ * Space for AX.25 header and PID.
+ */
+ skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + 1);
+
+ dptr = skb_put(skb, skb_tailroom(skb));
+
+ lci1 = (rose->lci >> 8) & 0x0F;
+ lci2 = (rose->lci >> 0) & 0xFF;
+
+ switch (frametype) {
+ case ROSE_CALL_REQUEST:
+ *dptr++ = ROSE_GFI | lci1;
+ *dptr++ = lci2;
+ *dptr++ = frametype;
+ *dptr++ = ROSE_CALL_REQ_ADDR_LEN_VAL;
+ memcpy(dptr, &rose->dest_addr, ROSE_ADDR_LEN);
+ dptr += ROSE_ADDR_LEN;
+ memcpy(dptr, &rose->source_addr, ROSE_ADDR_LEN);
+ dptr += ROSE_ADDR_LEN;
+ memcpy(dptr, buffer, faclen);
+ dptr += faclen;
+ break;
+
+ case ROSE_CALL_ACCEPTED:
+ *dptr++ = ROSE_GFI | lci1;
+ *dptr++ = lci2;
+ *dptr++ = frametype;
+ *dptr++ = 0x00; /* Address length */
+ *dptr++ = 0; /* Facilities length */
+ break;
+
+ case ROSE_CLEAR_REQUEST:
+ *dptr++ = ROSE_GFI | lci1;
+ *dptr++ = lci2;
+ *dptr++ = frametype;
+ *dptr++ = rose->cause;
+ *dptr++ = rose->diagnostic;
+ break;
+
+ case ROSE_RESET_REQUEST:
+ *dptr++ = ROSE_GFI | lci1;
+ *dptr++ = lci2;
+ *dptr++ = frametype;
+ *dptr++ = ROSE_DTE_ORIGINATED;
+ *dptr++ = 0;
+ break;
+
+ case ROSE_RR:
+ case ROSE_RNR:
+ *dptr++ = ROSE_GFI | lci1;
+ *dptr++ = lci2;
+ *dptr = frametype;
+ *dptr++ |= (rose->vr << 5) & 0xE0;
+ break;
+
+ case ROSE_CLEAR_CONFIRMATION:
+ case ROSE_RESET_CONFIRMATION:
+ *dptr++ = ROSE_GFI | lci1;
+ *dptr++ = lci2;
+ *dptr++ = frametype;
+ break;
+
+ default:
+ printk(KERN_ERR "ROSE: rose_write_internal - invalid frametype %02X\n", frametype);
+ kfree_skb(skb);
+ return;
+ }
+
+ rose_transmit_link(skb, rose->neighbour);
+}
+
+int rose_decode(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 ROSE_CALL_REQUEST:
+ case ROSE_CALL_ACCEPTED:
+ case ROSE_CLEAR_REQUEST:
+ case ROSE_CLEAR_CONFIRMATION:
+ case ROSE_RESET_REQUEST:
+ case ROSE_RESET_CONFIRMATION:
+ return frame[2];
+ default:
+ break;
+ }
+
+ if ((frame[2] & 0x1F) == ROSE_RR ||
+ (frame[2] & 0x1F) == ROSE_RNR) {
+ *nr = (frame[2] >> 5) & 0x07;
+ return frame[2] & 0x1F;
+ }
+
+ if ((frame[2] & 0x01) == ROSE_DATA) {
+ *q = (frame[0] & ROSE_Q_BIT) == ROSE_Q_BIT;
+ *d = (frame[0] & ROSE_D_BIT) == ROSE_D_BIT;
+ *m = (frame[2] & ROSE_M_BIT) == ROSE_M_BIT;
+ *nr = (frame[2] >> 5) & 0x07;
+ *ns = (frame[2] >> 1) & 0x07;
+ return ROSE_DATA;
+ }
+
+ return ROSE_ILLEGAL;
+}
+
+static int rose_parse_national(unsigned char *p, struct rose_facilities_struct *facilities, int len)
+{
+ unsigned char *pt;
+ unsigned char l, lg, n = 0;
+ int fac_national_digis_received = 0;
+
+ do {
+ switch (*p & 0xC0) {
+ case 0x00:
+ if (len < 2)
+ return -1;
+ p += 2;
+ n += 2;
+ len -= 2;
+ break;
+
+ case 0x40:
+ if (len < 3)
+ return -1;
+ if (*p == FAC_NATIONAL_RAND)
+ facilities->rand = ((p[1] << 8) & 0xFF00) + ((p[2] << 0) & 0x00FF);
+ p += 3;
+ n += 3;
+ len -= 3;
+ break;
+
+ case 0x80:
+ if (len < 4)
+ return -1;
+ p += 4;
+ n += 4;
+ len -= 4;
+ break;
+
+ case 0xC0:
+ if (len < 2)
+ return -1;
+ l = p[1];
+ if (len < 2 + l)
+ return -1;
+ if (*p == FAC_NATIONAL_DEST_DIGI) {
+ if (!fac_national_digis_received) {
+ if (l < AX25_ADDR_LEN)
+ return -1;
+ memcpy(&facilities->source_digis[0], p + 2, AX25_ADDR_LEN);
+ facilities->source_ndigis = 1;
+ }
+ }
+ else if (*p == FAC_NATIONAL_SRC_DIGI) {
+ if (!fac_national_digis_received) {
+ if (l < AX25_ADDR_LEN)
+ return -1;
+ memcpy(&facilities->dest_digis[0], p + 2, AX25_ADDR_LEN);
+ facilities->dest_ndigis = 1;
+ }
+ }
+ else if (*p == FAC_NATIONAL_FAIL_CALL) {
+ if (l < AX25_ADDR_LEN)
+ return -1;
+ memcpy(&facilities->fail_call, p + 2, AX25_ADDR_LEN);
+ }
+ else if (*p == FAC_NATIONAL_FAIL_ADD) {
+ if (l < 1 + ROSE_ADDR_LEN)
+ return -1;
+ memcpy(&facilities->fail_addr, p + 3, ROSE_ADDR_LEN);
+ }
+ else if (*p == FAC_NATIONAL_DIGIS) {
+ if (l % AX25_ADDR_LEN)
+ return -1;
+ fac_national_digis_received = 1;
+ facilities->source_ndigis = 0;
+ facilities->dest_ndigis = 0;
+ for (pt = p + 2, lg = 0 ; lg < l ; pt += AX25_ADDR_LEN, lg += AX25_ADDR_LEN) {
+ if (pt[6] & AX25_HBIT) {
+ if (facilities->dest_ndigis >= ROSE_MAX_DIGIS)
+ return -1;
+ memcpy(&facilities->dest_digis[facilities->dest_ndigis++], pt, AX25_ADDR_LEN);
+ } else {
+ if (facilities->source_ndigis >= ROSE_MAX_DIGIS)
+ return -1;
+ memcpy(&facilities->source_digis[facilities->source_ndigis++], pt, AX25_ADDR_LEN);
+ }
+ }
+ }
+ p += l + 2;
+ n += l + 2;
+ len -= l + 2;
+ break;
+ }
+ } while (*p != 0x00 && len > 0);
+
+ return n;
+}
+
+static int rose_parse_ccitt(unsigned char *p, struct rose_facilities_struct *facilities, int len)
+{
+ unsigned char l, n = 0;
+ char callsign[11];
+
+ do {
+ switch (*p & 0xC0) {
+ case 0x00:
+ if (len < 2)
+ return -1;
+ p += 2;
+ n += 2;
+ len -= 2;
+ break;
+
+ case 0x40:
+ if (len < 3)
+ return -1;
+ p += 3;
+ n += 3;
+ len -= 3;
+ break;
+
+ case 0x80:
+ if (len < 4)
+ return -1;
+ p += 4;
+ n += 4;
+ len -= 4;
+ break;
+
+ case 0xC0:
+ if (len < 2)
+ return -1;
+ l = p[1];
+
+ /* Prevent overflows*/
+ if (l < 10 || l > 20)
+ return -1;
+
+ if (*p == FAC_CCITT_DEST_NSAP) {
+ memcpy(&facilities->source_addr, p + 7, ROSE_ADDR_LEN);
+ memcpy(callsign, p + 12, l - 10);
+ callsign[l - 10] = '\0';
+ asc2ax(&facilities->source_call, callsign);
+ }
+ if (*p == FAC_CCITT_SRC_NSAP) {
+ memcpy(&facilities->dest_addr, p + 7, ROSE_ADDR_LEN);
+ memcpy(callsign, p + 12, l - 10);
+ callsign[l - 10] = '\0';
+ asc2ax(&facilities->dest_call, callsign);
+ }
+ p += l + 2;
+ n += l + 2;
+ len -= l + 2;
+ break;
+ }
+ } while (*p != 0x00 && len > 0);
+
+ return n;
+}
+
+int rose_parse_facilities(unsigned char *p, unsigned packet_len,
+ struct rose_facilities_struct *facilities)
+{
+ int facilities_len, len;
+
+ facilities_len = *p++;
+
+ if (facilities_len == 0 || (unsigned int)facilities_len > packet_len)
+ return 0;
+
+ while (facilities_len >= 3 && *p == 0x00) {
+ facilities_len--;
+ p++;
+
+ switch (*p) {
+ case FAC_NATIONAL: /* National */
+ len = rose_parse_national(p + 1, facilities, facilities_len - 1);
+ break;
+
+ case FAC_CCITT: /* CCITT */
+ len = rose_parse_ccitt(p + 1, facilities, facilities_len - 1);
+ break;
+
+ default:
+ printk(KERN_DEBUG "ROSE: rose_parse_facilities - unknown facilities family %02X\n", *p);
+ len = 1;
+ break;
+ }
+
+ if (len < 0)
+ return 0;
+ if (WARN_ON(len >= facilities_len))
+ return 0;
+ facilities_len -= len + 1;
+ p += len + 1;
+ }
+
+ return facilities_len == 0;
+}
+
+static int rose_create_facilities(unsigned char *buffer, struct rose_sock *rose)
+{
+ unsigned char *p = buffer + 1;
+ char *callsign;
+ char buf[11];
+ int len, nb;
+
+ /* National Facilities */
+ if (rose->rand != 0 || rose->source_ndigis == 1 || rose->dest_ndigis == 1) {
+ *p++ = 0x00;
+ *p++ = FAC_NATIONAL;
+
+ if (rose->rand != 0) {
+ *p++ = FAC_NATIONAL_RAND;
+ *p++ = (rose->rand >> 8) & 0xFF;
+ *p++ = (rose->rand >> 0) & 0xFF;
+ }
+
+ /* Sent before older facilities */
+ if ((rose->source_ndigis > 0) || (rose->dest_ndigis > 0)) {
+ int maxdigi = 0;
+ *p++ = FAC_NATIONAL_DIGIS;
+ *p++ = AX25_ADDR_LEN * (rose->source_ndigis + rose->dest_ndigis);
+ for (nb = 0 ; nb < rose->source_ndigis ; nb++) {
+ if (++maxdigi >= ROSE_MAX_DIGIS)
+ break;
+ memcpy(p, &rose->source_digis[nb], AX25_ADDR_LEN);
+ p[6] |= AX25_HBIT;
+ p += AX25_ADDR_LEN;
+ }
+ for (nb = 0 ; nb < rose->dest_ndigis ; nb++) {
+ if (++maxdigi >= ROSE_MAX_DIGIS)
+ break;
+ memcpy(p, &rose->dest_digis[nb], AX25_ADDR_LEN);
+ p[6] &= ~AX25_HBIT;
+ p += AX25_ADDR_LEN;
+ }
+ }
+
+ /* For compatibility */
+ if (rose->source_ndigis > 0) {
+ *p++ = FAC_NATIONAL_SRC_DIGI;
+ *p++ = AX25_ADDR_LEN;
+ memcpy(p, &rose->source_digis[0], AX25_ADDR_LEN);
+ p += AX25_ADDR_LEN;
+ }
+
+ /* For compatibility */
+ if (rose->dest_ndigis > 0) {
+ *p++ = FAC_NATIONAL_DEST_DIGI;
+ *p++ = AX25_ADDR_LEN;
+ memcpy(p, &rose->dest_digis[0], AX25_ADDR_LEN);
+ p += AX25_ADDR_LEN;
+ }
+ }
+
+ *p++ = 0x00;
+ *p++ = FAC_CCITT;
+
+ *p++ = FAC_CCITT_DEST_NSAP;
+
+ callsign = ax2asc(buf, &rose->dest_call);
+
+ *p++ = strlen(callsign) + 10;
+ *p++ = (strlen(callsign) + 9) * 2; /* ??? */
+
+ *p++ = 0x47; *p++ = 0x00; *p++ = 0x11;
+ *p++ = ROSE_ADDR_LEN * 2;
+ memcpy(p, &rose->dest_addr, ROSE_ADDR_LEN);
+ p += ROSE_ADDR_LEN;
+
+ memcpy(p, callsign, strlen(callsign));
+ p += strlen(callsign);
+
+ *p++ = FAC_CCITT_SRC_NSAP;
+
+ callsign = ax2asc(buf, &rose->source_call);
+
+ *p++ = strlen(callsign) + 10;
+ *p++ = (strlen(callsign) + 9) * 2; /* ??? */
+
+ *p++ = 0x47; *p++ = 0x00; *p++ = 0x11;
+ *p++ = ROSE_ADDR_LEN * 2;
+ memcpy(p, &rose->source_addr, ROSE_ADDR_LEN);
+ p += ROSE_ADDR_LEN;
+
+ memcpy(p, callsign, strlen(callsign));
+ p += strlen(callsign);
+
+ len = p - buffer;
+ buffer[0] = len - 1;
+
+ return len;
+}
+
+void rose_disconnect(struct sock *sk, int reason, int cause, int diagnostic)
+{
+ struct rose_sock *rose = rose_sk(sk);
+
+ rose_stop_timer(sk);
+ rose_stop_idletimer(sk);
+
+ rose_clear_queues(sk);
+
+ rose->lci = 0;
+ rose->state = ROSE_STATE_0;
+
+ if (cause != -1)
+ rose->cause = cause;
+
+ if (diagnostic != -1)
+ rose->diagnostic = diagnostic;
+
+ sk->sk_state = TCP_CLOSE;
+ sk->sk_err = reason;
+ sk->sk_shutdown |= SEND_SHUTDOWN;
+
+ if (!sock_flag(sk, SOCK_DEAD)) {
+ sk->sk_state_change(sk);
+ sock_set_flag(sk, SOCK_DEAD);
+ }
+}