diff --git a/Makefile.am b/Makefile.am index 50be3fd5..03902584 100644 --- a/Makefile.am +++ b/Makefile.am @@ -57,7 +57,7 @@ gatchat_sources = gatchat/gatchat.h gatchat/gatchat.c \ gatchat/gat.h \ gatchat/gatserver.h gatchat/gatserver.c \ gatchat/gatppp.c gatchat/gatppp.h \ - gatchat/ppp.c gatchat/ppp.h gatchat/ppp_cp.h \ + gatchat/ppp.h gatchat/ppp_cp.h \ gatchat/ppp_cp.c gatchat/ppp_lcp.c \ gatchat/ppp_auth.c gatchat/ppp_net.c diff --git a/gatchat/gatppp.c b/gatchat/gatppp.c index 8cac7195..1a6562a8 100644 --- a/gatchat/gatppp.c +++ b/gatchat/gatppp.c @@ -29,6 +29,7 @@ #include #include #include +#include #include #include @@ -37,6 +38,506 @@ #include "gatppp.h" #include "ppp.h" +#define PPPINITFCS16 0xffff /* Initial FCS value */ +#define PPPGOODFCS16 0xf0b8 /* Good final FCS value */ + +struct frame_buffer { + gsize len; + guint8 bytes[0]; +}; + +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, struct frame_buffer *frame) +{ + guint protocol = ppp_proto(frame->bytes); + guint8 *packet = ppp_info(frame->bytes); + struct ppp_packet_handler *h; + GList *list; + + if (!frame) + return; + + /* + * 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); + } else + lcp_protocol_reject(ppp->lcp, frame->bytes, frame->len); + + g_free(frame); +} + +/* XXX - Implement PFC and ACFC */ +static struct frame_buffer *ppp_decode(GAtPPP *ppp, guint8 *frame) +{ + guint8 *data; + guint pos; + int i; + guint16 fcs; + struct frame_buffer *fb; + + fb = g_try_malloc0(sizeof(struct frame_buffer) + ppp->mru + 10); + if (!fb) + return NULL; + data = fb->bytes; + + /* skip the first flag char */ + pos = 1; + + fcs = PPPINITFCS16; + i = 0; + + /* 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]; + + fcs = ppp_fcs(fcs, data[i]); + + i++; pos++; + } + + fb->len = i; + + /* see if we have a good FCS */ + if (fcs != PPPGOODFCS16) { + g_free(fb); + return NULL; + } + + return fb; +} + +static void ppp_feed(GAtPPP *ppp, guint8 *data, gsize len) +{ + guint pos = 0; + struct frame_buffer *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); + + /* process receive frame */ + ppp_recv(ppp, 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]; + } +} + +static void ppp_record(GAtPPP *ppp, gboolean in, guint8 *data, guint16 length) +{ + guint16 len = htons(length); + guint32 ts; + struct timeval now; + unsigned char id; + int err; + + if (ppp->record_fd < 0) + return; + + gettimeofday(&now, NULL); + ts = htonl(now.tv_sec & 0xffffffff); + + id = 0x07; + err = write(ppp->record_fd, &id, 1); + err = write(ppp->record_fd, &ts, 4); + + id = in ? 0x02 : 0x01; + err = write(ppp->record_fd, &id, 1); + err = write(ppp->record_fd, &len, 2); + err = write(ppp->record_fd, data, length); +} + +/* + * 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); + ppp_record(ppp, FALSE, frame, bytes_written); + + 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)) + return FALSE; + + if (cond & G_IO_IN) { + status = g_io_channel_read_chars(channel, buf, 256, + &bytes_read, &error); + if (bytes_read > 0) { + ppp_record(ppp, TRUE, (guint8 *) buf, bytes_read); + 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 */ + lcp_close(ppp->lcp); +} + +static void ppp_link_establishment(GAtPPP *ppp) +{ + /* signal UP event to LCP */ + lcp_establish(ppp->lcp); +} + +static void ppp_terminate(GAtPPP *ppp) +{ + /* signal DOWN event to LCP */ + lcp_terminate(ppp->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) +{ + /* notify interested parties */ + if (ppp->disconnect_cb) + ppp->disconnect_cb(ppp->disconnect_data); + + if (g_atomic_int_get(&ppp->ref_count)) + return; + + /* cleanup modem channel */ + g_source_remove(ppp->modem_watch); + g_io_channel_unref(ppp->modem); + + /* remove lcp */ + lcp_free(ppp->lcp); + + /* remove auth */ + auth_free(ppp->auth); + + g_free(ppp); +} + +static void ppp_network(GAtPPP *ppp) +{ + /* bring network phase up */ + ppp_net_open(ppp->net); +} + +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; + } +} + +/* + * send the event handler a new event to process + */ +void ppp_generate_event(GAtPPP *ppp, enum ppp_event event) +{ + 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); + } +} + +void ppp_set_auth(GAtPPP *ppp, guint8* auth_data) +{ + guint16 proto = get_host_short(auth_data); + + switch (proto) { + case CHAP_PROTOCOL: + /* get the algorithm */ + auth_set_proto(ppp->auth, proto, auth_data[2]); + break; + default: + g_printerr("unknown authentication proto\n"); + break; + } +} + +void ppp_set_recv_accm(GAtPPP *ppp, guint32 accm) +{ + ppp->recv_accm = accm; +} + +guint32 ppp_get_xmit_accm(GAtPPP *ppp) +{ + return ppp->xmit_accm[0]; +} + +void ppp_set_pfc(GAtPPP *ppp, gboolean pfc) +{ + ppp->pfc = pfc; +} + +gboolean ppp_get_pfc(GAtPPP *ppp) +{ + return ppp->pfc; +} + +void ppp_set_acfc(GAtPPP *ppp, gboolean acfc) +{ + ppp->acfc = acfc; +} + +gboolean ppp_get_acfc(GAtPPP *ppp) +{ + return ppp->acfc; +} + /* Administrative Open */ void g_at_ppp_open(GAtPPP *ppp) { diff --git a/gatchat/gatppp.h b/gatchat/gatppp.h index f22ee7aa..11495435 100644 --- a/gatchat/gatppp.h +++ b/gatchat/gatppp.h @@ -29,6 +29,7 @@ extern "C" { #include "gat.h" struct _GAtPPP; + typedef struct _GAtPPP GAtPPP; typedef enum _GAtPPPConnectStatus { diff --git a/gatchat/ppp.c b/gatchat/ppp.c deleted file mode 100644 index 0e4e8354..00000000 --- a/gatchat/ppp.c +++ /dev/null @@ -1,538 +0,0 @@ -/* - * - * 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 -#endif - -#include -#include -#include -#include -#include -#include -#include - -#include - -#include "gatutil.h" -#include "gatppp.h" -#include "ppp.h" - -#define PPPINITFCS16 0xffff /* Initial FCS value */ -#define PPPGOODFCS16 0xf0b8 /* Good final FCS value */ - -struct frame_buffer { - gsize len; - guint8 bytes[0]; -}; - -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, struct frame_buffer *frame) -{ - guint protocol = ppp_proto(frame->bytes); - guint8 *packet = ppp_info(frame->bytes); - struct ppp_packet_handler *h; - GList *list; - - if (!frame) - return; - - /* - * 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); - } else - lcp_protocol_reject(ppp->lcp, frame->bytes, frame->len); - - g_free(frame); -} - -/* XXX - Implement PFC and ACFC */ -static struct frame_buffer *ppp_decode(GAtPPP *ppp, guint8 *frame) -{ - guint8 *data; - guint pos; - int i; - guint16 fcs; - struct frame_buffer *fb; - - fb = g_try_malloc0(sizeof(struct frame_buffer) + ppp->mru + 10); - if (!fb) - return NULL; - data = fb->bytes; - - /* skip the first flag char */ - pos = 1; - - fcs = PPPINITFCS16; - i = 0; - - /* 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]; - - fcs = ppp_fcs(fcs, data[i]); - - i++; pos++; - } - - fb->len = i; - - /* see if we have a good FCS */ - if (fcs != PPPGOODFCS16) { - g_free(fb); - return NULL; - } - - return fb; -} - -static void ppp_feed(GAtPPP *ppp, guint8 *data, gsize len) -{ - guint pos = 0; - struct frame_buffer *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); - - /* process receive frame */ - ppp_recv(ppp, 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]; - } -} - -static void ppp_record(GAtPPP *ppp, gboolean in, guint8 *data, guint16 length) -{ - guint16 len = htons(length); - guint32 ts; - struct timeval now; - unsigned char id; - int err; - - if (ppp->record_fd < 0) - return; - - gettimeofday(&now, NULL); - ts = htonl(now.tv_sec & 0xffffffff); - - id = 0x07; - err = write(ppp->record_fd, &id, 1); - err = write(ppp->record_fd, &ts, 4); - - id = in ? 0x02 : 0x01; - err = write(ppp->record_fd, &id, 1); - err = write(ppp->record_fd, &len, 2); - err = write(ppp->record_fd, data, length); -} - -/* - * 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); - ppp_record(ppp, FALSE, frame, bytes_written); - - 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)) - return FALSE; - - if (cond & G_IO_IN) { - status = g_io_channel_read_chars(channel, buf, 256, - &bytes_read, &error); - if (bytes_read > 0) { - ppp_record(ppp, TRUE, (guint8 *) buf, bytes_read); - 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 */ - lcp_close(ppp->lcp); -} - -static void ppp_link_establishment(GAtPPP *ppp) -{ - /* signal UP event to LCP */ - lcp_establish(ppp->lcp); -} - -static void ppp_terminate(GAtPPP *ppp) -{ - /* signal DOWN event to LCP */ - lcp_terminate(ppp->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) -{ - /* notify interested parties */ - if (ppp->disconnect_cb) - ppp->disconnect_cb(ppp->disconnect_data); - - if (g_atomic_int_get(&ppp->ref_count)) - return; - - /* cleanup modem channel */ - g_source_remove(ppp->modem_watch); - g_io_channel_unref(ppp->modem); - - /* remove lcp */ - lcp_free(ppp->lcp); - - /* remove auth */ - auth_free(ppp->auth); - - g_free(ppp); -} - -static void ppp_network(GAtPPP *ppp) -{ - /* bring network phase up */ - ppp_net_open(ppp->net); -} - -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; - } -} - -/* - * send the event handler a new event to process - */ -void ppp_generate_event(GAtPPP *ppp, enum ppp_event event) -{ - 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); - } -} - -void ppp_set_auth(GAtPPP *ppp, guint8* auth_data) -{ - guint16 proto = get_host_short(auth_data); - - switch (proto) { - case CHAP_PROTOCOL: - /* get the algorithm */ - auth_set_proto(ppp->auth, proto, auth_data[2]); - break; - default: - g_printerr("unknown authentication proto\n"); - break; - } -} - -void ppp_set_recv_accm(GAtPPP *ppp, guint32 accm) -{ - ppp->recv_accm = accm; -} - -guint32 ppp_get_xmit_accm(GAtPPP *ppp) -{ - return ppp->xmit_accm[0]; -} - -void ppp_set_pfc(GAtPPP *ppp, gboolean pfc) -{ - ppp->pfc = pfc; -} - -gboolean ppp_get_pfc(GAtPPP *ppp) -{ - return ppp->pfc; -} - -void ppp_set_acfc(GAtPPP *ppp, gboolean acfc) -{ - ppp->acfc = acfc; -} - -gboolean ppp_get_acfc(GAtPPP *ppp) -{ - return ppp->acfc; -}