--- /dev/null
+/*
+ *
+ * PPP library with GLib integration
+ *
+ * Copyright (C) 2009-2010 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+#include <termios.h>
+#include <arpa/inet.h>
+
+#include <glib.h>
+
+#include "gatutil.h"
+#include "gatppp.h"
+#include "ppp.h"
+
+#define PPPINITFCS16 0xffff /* Initial FCS value */
+#define PPPGOODFCS16 0xf0b8 /* Good final FCS value */
+
+static GList *packet_handlers = NULL;
+
+void ppp_register_packet_handler(struct ppp_packet_handler *handler)
+{
+ packet_handlers = g_list_append(packet_handlers, handler);
+}
+
+/*
+ * FCS lookup table copied from rfc1662.
+ */
+static guint16 fcstab[256] = {
+ 0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
+ 0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
+ 0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
+ 0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
+ 0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
+ 0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
+ 0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
+ 0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
+ 0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
+ 0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
+ 0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
+ 0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
+ 0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
+ 0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
+ 0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
+ 0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
+ 0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
+ 0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
+ 0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
+ 0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
+ 0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
+ 0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
+ 0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
+ 0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
+ 0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
+ 0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
+ 0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
+ 0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
+ 0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
+ 0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
+ 0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
+ 0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78
+};
+
+/*
+ * Calculate a new fcs given the current fcs and the new data.
+ * copied from rfc1662
+ *
+ * The FCS field is calculated over all bits of the Address, Control,
+ * Protocol, Information and Padding fields, not including any start
+ * and stop bits (asynchronous) nor any bits (synchronous) or octets
+ * (asynchronous or synchronous) inserted for transparency. This
+ * also does not include the Flag Sequences nor the FCS field itself.
+ */
+static guint16 ppp_fcs(guint16 fcs, guint8 c)
+{
+ guint16 new_fcs;
+
+ new_fcs = (fcs >> 8) ^ fcstab[(fcs ^ c) & 0xff];
+ return new_fcs;
+}
+
+/*
+ * escape any chars less than 0x20, and check the transmit accm table to
+ * see if this character should be escaped.
+ */
+static gboolean ppp_escape(GAtPPP *ppp, guint8 c, gboolean lcp)
+{
+ if ((lcp && c < 0x20) || (ppp->xmit_accm[c >> 5] & (1 << (c & 0x1f))))
+ return TRUE;
+ return FALSE;
+}
+
+static void ppp_put(GAtPPP *ppp, guint8 *buf, int *pos,
+ guint8 c, gboolean lcp)
+{
+ int i = *pos;
+
+ /* escape characters if needed, copy into buf, increment pos */
+ if (ppp_escape(ppp, c, lcp)) {
+ buf[i++] = PPP_ESC;
+ buf[i++] = c ^ 0x20;
+ } else
+ buf[i++] = c;
+ *pos = i;
+}
+
+/* XXX implement PFC and ACFC */
+static guint8 *ppp_encode(GAtPPP *ppp, guint8 *data, int len,
+ guint *newlen)
+{
+ int pos = 0;
+ int i = 0;
+ guint16 fcs = PPPINITFCS16;
+ guint16 proto = get_host_short(data);
+ gboolean lcp = (proto == LCP_PROTOCOL);
+ guint8 *frame = g_try_malloc0(BUFFERSZ);
+ if (!frame)
+ return NULL;
+
+ /* copy in the HDLC framing */
+ frame[pos++] = PPP_FLAG_SEQ;
+
+ /* from here till end flag, calculate FCS over each character */
+ fcs = ppp_fcs(fcs, PPP_ADDR_FIELD);
+ ppp_put(ppp, frame, &pos, PPP_ADDR_FIELD, lcp);
+ fcs = ppp_fcs(fcs, PPP_CTRL);
+ ppp_put(ppp, frame, &pos, PPP_CTRL, lcp);
+
+ /*
+ * for each byte, first calculate FCS, then do escaping if
+ * neccessary
+ */
+ while (len--) {
+ fcs = ppp_fcs(fcs, data[i]);
+ ppp_put(ppp, frame, &pos, data[i++], lcp);
+ }
+
+ /* add FCS */
+ fcs ^= 0xffff; /* complement */
+ ppp_put(ppp, frame, &pos, (guint8)(fcs & 0x00ff), lcp);
+ ppp_put(ppp, frame, &pos, (guint8)((fcs >> 8) & 0x00ff), lcp);
+
+ /* add flag */
+ frame[pos++] = PPP_FLAG_SEQ;
+
+ *newlen = pos;
+ return frame;
+}
+
+static gint is_proto_handler(gconstpointer a, gconstpointer b)
+{
+ const struct ppp_packet_handler *h = a;
+ const guint16 proto = (guint16) GPOINTER_TO_UINT(b);
+
+ if (h->proto == proto)
+ return 0;
+ else
+ return -1;
+}
+
+/* called when we have received a complete ppp frame */
+static void ppp_recv(GAtPPP *ppp)
+{
+ guint16 protocol;
+ guint8 *frame, *packet;
+ GList *list;
+ struct ppp_packet_handler *h;
+
+ /* pop frames off of receive queue */
+ while ((frame = g_queue_pop_head(ppp->recv_queue))) {
+ protocol = ppp_proto(frame);
+ packet = ppp_info(frame);
+
+ /*
+ * check to see if we have a protocol handler
+ * registered for this packet
+ */
+ list = g_list_find_custom(packet_handlers,
+ GUINT_TO_POINTER(protocol),
+ is_proto_handler);
+ if (list) {
+ h = list->data;
+ h->handler(h->priv, packet);
+ }
+ g_free(frame);
+ }
+}
+
+/* XXX - Implement PFC and ACFC */
+static guint8 *ppp_decode(GAtPPP *ppp, guint8 *frame)
+{
+ guint8 *data;
+ guint pos = 0;
+ int i = 0;
+ int len;
+ guint16 fcs;
+
+ data = g_try_malloc0(ppp->mru + 10);
+ if (!data)
+ return NULL;
+
+ /* skip the first flag char */
+ pos++;
+
+ /* TBD - how to deal with recv_accm */
+ while (frame[pos] != PPP_FLAG_SEQ) {
+ /* scan for escape character */
+ if (frame[pos] == PPP_ESC) {
+ /* skip that char */
+ pos++;
+ data[i] = frame[pos] ^ 0x20;
+ } else
+ data[i] = frame[pos];
+ i++; pos++;
+ }
+
+ len = i;
+
+ /* see if we have a good FCS */
+ fcs = PPPINITFCS16;
+ for (i = 0; i < len; i++)
+ fcs = ppp_fcs(fcs, data[i]);
+
+ if (fcs != PPPGOODFCS16) {
+ g_free(data);
+ return NULL;
+ }
+ return data;
+}
+
+static void ppp_feed(GAtPPP *ppp, guint8 *data, gsize len)
+{
+ guint pos = 0;
+ guint8 *frame;
+
+ /* collect bytes until we detect we have received a complete frame */
+ /* examine the data. If we are at the beginning of a new frame,
+ * allocate memory to buffer the frame.
+ */
+
+ for (pos = 0; pos < len; pos++) {
+ if (data[pos] == PPP_FLAG_SEQ) {
+ if (ppp->index != 0) {
+ /* store last flag character & decode */
+ ppp->buffer[ppp->index++] = data[pos];
+ frame = ppp_decode(ppp, ppp->buffer);
+
+ /* push decoded frame onto receive queue */
+ if (frame)
+ g_queue_push_tail(ppp->recv_queue,
+ frame);
+
+ /* zero buffer */
+ memset(ppp->buffer, 0, BUFFERSZ);
+ ppp->index = 0;
+ continue;
+ }
+ }
+ /* copy byte to buffer */
+ if (ppp->index < BUFFERSZ)
+ ppp->buffer[ppp->index++] = data[pos];
+ }
+ /* process receive queue */
+ ppp_recv(ppp);
+}
+
+/*
+ * transmit out through the lower layer interface
+ *
+ * infolen - length of the information part of the packet
+ */
+void ppp_transmit(GAtPPP *ppp, guint8 *packet, guint infolen)
+{
+ guint8 *frame;
+ guint framelen;
+ GError *error = NULL;
+ GIOStatus status;
+ gsize bytes_written;
+
+ /*
+ * do the octet stuffing. Add 2 bytes to the infolen to
+ * include the protocol field.
+ */
+ frame = ppp_encode(ppp, packet, infolen + 2, &framelen);
+ if (!frame) {
+ g_printerr("Failed to encode packet to transmit\n");
+ return;
+ }
+
+ /* transmit through the lower layer interface */
+ /*
+ * TBD - should we just put this on a queue and transmit when
+ * we won't block, or allow ourselves to block here?
+ */
+ status = g_io_channel_write_chars(ppp->modem, (gchar *) frame,
+ framelen, &bytes_written, &error);
+
+ g_free(frame);
+}
+
+gboolean ppp_cb(GIOChannel *channel, GIOCondition cond, gpointer data)
+{
+ GAtPPP *ppp = data;
+ GIOStatus status;
+ gchar buf[256];
+ gsize bytes_read;
+ GError *error = NULL;
+
+ if (cond & (G_IO_NVAL | G_IO_ERR | G_IO_HUP)) {
+ g_print("G_IO_NVAL | G_IO_ERR");
+ return FALSE;
+ }
+
+ if (cond & G_IO_IN) {
+ status = g_io_channel_read_chars(channel, buf, 256,
+ &bytes_read, &error);
+ if (bytes_read > 0)
+ ppp_feed(ppp, (guint8 *)buf, bytes_read);
+ if (status != G_IO_STATUS_NORMAL && status != G_IO_STATUS_AGAIN)
+ return FALSE;
+ }
+
+ return TRUE;
+}
+
+/* Administrative Close */
+void ppp_close(GAtPPP *ppp)
+{
+ /* send a CLOSE event to the lcp layer */
+}
+
+static void ppp_link_establishment(GAtPPP *ppp)
+{
+ /* signal UP event to LCP */
+}
+
+static void ppp_terminate(GAtPPP *ppp)
+{
+ /* signal DOWN event to LCP */
+}
+
+static void ppp_authenticate(GAtPPP *ppp)
+{
+ /* we don't do authentication right now, so send NONE */
+ if (!ppp->auth_proto)
+ ppp_generate_event(ppp, PPP_NONE);
+ /* otherwise we need to wait for the peer to send us a challenge */
+}
+
+static void ppp_dead(GAtPPP *ppp)
+{
+ /* re-initialize everything */
+}
+
+static void ppp_network(GAtPPP *ppp)
+{
+ /* bring network phase up */
+}
+
+static void ppp_transition_phase(GAtPPP *ppp, enum ppp_phase phase)
+{
+ /* don't do anything if we're already there */
+ if (ppp->phase == phase)
+ return;
+
+ /* set new phase */
+ ppp->phase = phase;
+
+ switch (phase) {
+ case PPP_ESTABLISHMENT:
+ ppp_link_establishment(ppp);
+ break;
+ case PPP_AUTHENTICATION:
+ ppp_authenticate(ppp);
+ break;
+ case PPP_TERMINATION:
+ ppp_terminate(ppp);
+ break;
+ case PPP_DEAD:
+ ppp_dead(ppp);
+ break;
+ case PPP_NETWORK:
+ ppp_network(ppp);
+ break;
+ }
+
+}
+
+static void ppp_handle_event(GAtPPP *ppp)
+{
+ enum ppp_event event;
+
+ while ((event = GPOINTER_TO_UINT(g_queue_pop_head(ppp->event_queue)))){
+ switch (event) {
+ case PPP_UP:
+ /* causes transition to ppp establishment */
+ ppp_transition_phase(ppp, PPP_ESTABLISHMENT);
+ break;
+ case PPP_OPENED:
+ ppp_transition_phase(ppp, PPP_AUTHENTICATION);
+ break;
+ case PPP_CLOSING:
+ /* causes transition to termination phase */
+ ppp_transition_phase(ppp, PPP_TERMINATION);
+ break;
+ case PPP_DOWN:
+ /* cases transition to dead phase */
+ ppp_transition_phase(ppp, PPP_DEAD);
+ break;
+ case PPP_NONE:
+ case PPP_SUCCESS:
+ /* causes transition to network phase */
+ ppp_transition_phase(ppp, PPP_NETWORK);
+ break;
+ case PPP_FAIL:
+ if (ppp->phase == PPP_ESTABLISHMENT)
+ ppp_transition_phase(ppp, PPP_DEAD);
+ else if (ppp->phase == PPP_AUTHENTICATION)
+ ppp_transition_phase(ppp, PPP_TERMINATION);
+ }
+ }
+}
+
+/*
+ * send the event handler a new event to process
+ */
+void ppp_generate_event(GAtPPP *ppp, enum ppp_event event)
+{
+ g_queue_push_tail(ppp->event_queue, GUINT_TO_POINTER(event));
+ ppp_handle_event(ppp);
+}
projects / platform / upstream / ofono.git / commitdiff