/* * Copyright (C) 2012 by egnite GmbH * Copyright (C) 2008 by Szemzo András * Copyright (C) 2003-2004 by egnite Software GmbH * Copyright (c) 1996 - 2001 Brian Somers * based on work by Toshiharu OHNO * Internet Initiative Japan, Inc (IIJ) * * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * For additional information see http://www.ethernut.de/ */ /*! * \file dev/ppp_hdlc.c * \brief Generic AHDLC driver for PPP. * * \verbatim * $Id$ * \endverbatim */ #include #include #include #include #include #include #include #include #include #include #include #include /*! * \brief AHDLC receiver thread stack size. */ #ifndef NUT_THREAD_AHDLCRXSTACK #define NUT_THREAD_AHDLCRXSTACK 1024 #endif #define RXTHREADSTACK ((NUT_THREAD_AHDLCRXSTACK) * (NUT_THREAD_STACK_MULT) + (NUT_THREAD_STACK_ADD)) /*! * \brief Check character against Async-Control-Character-Map. * * Checks the 32-bit ACCM to see if the byte needs un-escaping */ #define IN_ACC_MAP(c, m) (( ((uint8_t) (c)) < 0x20) && ((m) & (1UL << (c))) != 0) /* * FCS lookup table. */ static const uint16_t 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 }; typedef struct _PPPHDLC_DCB PPPHDLC_DCB; struct _PPPHDLC_DCB { /* ! \brief Downlink device. */ int dcb_fd; /*! \brief HDLC mode change event queue. */ HANDLE dcb_mode_evt; /*! \brief Peer's Async-Control-Character-Map. */ uint32_t dcb_rx_accm; /*! \brief Our Async-Control-Character-Map. */ uint32_t dcb_tx_accm; /*! \brief Maximum receive and transmit MRU. */ uint_fast16_t dcb_mru; }; static PPPHDLC_DCB dcb_ppp0; static PPPHDLC_DCB dcb_ppp1; /*! * \brief Send byte to physical device. * * \return 0 on success, -1 in case of any errors. */ static int INLINE PppHdlcSendByte(int fd, uint8_t ch, uint8_t flush) { if (_write(fd, &ch, 1) != 1) return -1; return 0; } /* * Characters are properly escaped and checksum is updated. * * \return 0 on success, -1 in case of any errors. */ static int PppHdlcSend(PPPHDLC_DCB *dcb, const uint8_t *data, uint16_t len, uint16_t *txfcs) { uint16_t tbx; register uint16_t fcs; uint8_t ch; if (txfcs) fcs = *txfcs; else fcs = 0; while (len) { tbx = (uint16_t) ((uint8_t) fcs ^ *data); fcs >>= 8; fcs ^= fcstab[tbx]; if (IN_ACC_MAP(*data, dcb->dcb_tx_accm) || *data == AHDLC_FLAG || *data == AHDLC_ESCAPE) { ch = AHDLC_ESCAPE; if (PppHdlcSendByte(dcb->dcb_fd, AHDLC_ESCAPE, 0)) return -1; if (PppHdlcSendByte(dcb->dcb_fd, *data ^ AHDLC_TRANS, 0)) if (_write(dcb->dcb_fd, &ch, 1) != 1) return -1; } else if (PppHdlcSendByte(dcb->dcb_fd, *data, 0)) return -1; data++; len--; } if (txfcs) *txfcs = fcs; return 0; } /*! * \brief Send HDLC frame. * * \param dev Identifies the device to use. * \param nb Network buffer structure containing the packet to be sent. * The structure must have been allocated by a previous * call NutNetBufAlloc(). * * \return 0 on success, -1 in case of any errors. */ static int PppHdlcOutput(NUTDEVICE *dev, NETBUF *nb) { uint16_t txfcs; PPPHDLC_DCB *dcb = dev->dev_dcb; uint_fast16_t sz; /* * Calculate the number of bytes to be send. Do not * send packets larger than transmit mru. */ sz = nb->nb_dl.sz + nb->nb_nw.sz + nb->nb_tp.sz + nb->nb_ap.sz; if (sz > dcb->dcb_mru) { return -1; } /* Send the starting flag. */ PppHdlcSendByte(dcb->dcb_fd, AHDLC_FLAG, 0); /* Initialize the checksum and send the NETBUF. */ txfcs = AHDLC_INITFCS; if (PppHdlcSend(dcb, nb->nb_dl.vp, nb->nb_dl.sz, &txfcs)) return -1; if (PppHdlcSend(dcb, nb->nb_nw.vp, nb->nb_nw.sz, &txfcs)) return -1; if (PppHdlcSend(dcb, nb->nb_tp.vp, nb->nb_tp.sz, &txfcs)) return -1; if (PppHdlcSend(dcb, nb->nb_ap.vp, nb->nb_ap.sz, &txfcs)) return -1; /* Send the checksum and the final flag. */ txfcs ^= 0xffff; if (PppHdlcSend(dcb, (uint8_t *) & txfcs, 2, 0)) return -1; PppHdlcSendByte(dcb->dcb_fd, AHDLC_FLAG, 1); return 0; } /*! \fn PppHdlcReceive(void *arg) * \brief Asynchronous HDLC receiver thread. * * Running at high priority. */ THREAD(PppHdlcReceive, arg) { NUTDEVICE *dev = (NUTDEVICE *) arg; PPPHDLC_DCB *dcb = (PPPHDLC_DCB *) dev->dev_dcb; NUTDEVICE *netdev = (NUTDEVICE *) dev->dev_icb; IFNET *ifn = (IFNET *) netdev->dev_icb; uint_fast8_t ch; uint8_t *rd_buf; uint8_t *rd_ptr; uint8_t *rx_buf; uint8_t *rx_ptr; static const int rd_siz = 64; int rd_len = 0; uint16_t rx_fcs = AHDLC_INITFCS; int rx_cnt = 0; uint_fast8_t inframe = 0; uint_fast8_t escaped = 0; uint32_t tmo = 1000; rd_buf = malloc(rd_siz); rd_ptr = rd_buf; _ioctl(dcb->dcb_fd, UART_SETREADTIMEOUT, &tmo); dev->dev_type = IFTYP_NET; dcb->dcb_mru = ifn->if_mtu; rx_buf = malloc(dcb->dcb_mru + 2); rx_ptr = rx_buf; /* Signal the link driver that we are up. */ ifn->if_send = PppHdlcOutput; netdev->dev_ioctl(netdev, LCP_LOWERUP, 0); NutEventPost(&dcb->dcb_mode_evt); for (;;) { /* Read next character from downlink. */ while (rd_len == 0) { rd_ptr = rd_buf; rd_len = _read(dcb->dcb_fd, rd_buf, rd_siz); /* Check, if the net interface is still attached. */ if (dev->dev_icb == NULL) { rd_len = -1; } } if (rd_len < 0) { /* Device error. */ break; } ch = *rd_ptr++; rd_len--; if (inframe) { if (ch != AHDLC_FLAG) { if (ch == AHDLC_ESCAPE) { /* Escape next character. */ escaped = 1; /* Jump to get next character. */ continue; } if (escaped) { /* Last character was escape. */ ch ^= AHDLC_TRANS; escaped = 0; } if (rx_cnt++ < dcb->dcb_mru + 2) { /* Update calculated checksum and store character in buffer. */ uint16_t tbx = (uint16_t) ((uint8_t) rx_fcs ^ ch); rx_fcs >>= 8; rx_fcs ^= fcstab[tbx]; *rx_ptr++ = ch; } else { /* Size overflow, skip this frame. */ inframe = 0; } /* Jump to get next character. */ continue; } /* Frame flag received, check length and checksum. */ if (rx_cnt >= 2 && rx_fcs == AHDLC_GOODFCS) { NETBUF *nb; /* Frame is valid. Create a NETBUF and pass it to the network specific receive handler. */ rx_cnt -= 2; nb = NutNetBufAlloc(NULL, NBAF_DATALINK, rx_cnt); if (nb) { memcpy(nb->nb_dl.vp, rx_buf, rx_cnt); (*ifn->if_recv) (netdev, nb); } } } /* If frame flag is received, re-sync frame processing. */ if (ch == AHDLC_FLAG) { inframe = 1; escaped = 0; rx_ptr = rx_buf; rx_cnt = 0; rx_fcs = AHDLC_INITFCS; } } /* Signal the link driver that we are down. */ netdev->dev_ioctl(netdev, LCP_LOWERDOWN, 0); dev->dev_type = IFTYP_CHAR; NutEventPost(&dcb->dcb_mode_evt); NutThreadExit(); for (;;); } /* * \brief Attach or detach the network interface. * * \param dev PPP device. * \param netdev Network device. * * \return 0 on success, -1 otherwise. */ static int PppHdlcAttach(NUTDEVICE *dev, NUTDEVICE *netdev) { PPPHDLC_DCB *dcb = (PPPHDLC_DCB *) dev->dev_dcb; if (netdev) { if (dev->dev_icb) { return -1; } dev->dev_icb = netdev; if (NutThreadCreate("ppphdlc", PppHdlcReceive, dev, RXTHREADSTACK) == NULL) { return -1; } } else if (dev->dev_icb == NULL) { return 0; } else { dev->dev_icb = NULL; } return NutEventWait(&dcb->dcb_mode_evt, 2000); } /*! * \brief Perform device specific control functions. * * \param dev Identifies the device that receives the device-control * function. * \param req Requested control function. The following functions are * handled by this device: * - \ref HDLC_SETIFNET * - \ref HDLC_GETIFNET * All other functions will be passed to the UART driver. * \param conf Points to a buffer that contains any data required for * the given control function or receives data from that * function. * * \return 0 on success, -1 otherwise. */ static int PppHdlcIoCtl(NUTDEVICE *dev, int req, void *conf) { int rc = 0; PPPHDLC_DCB *dcb; dcb = (PPPHDLC_DCB *) dev->dev_dcb; switch (req) { case HDLC_SETIFNET: rc = PppHdlcAttach(dev, *(NUTDEVICE **) conf); break; case HDLC_GETIFNET: *(NUTDEVICE **)conf = (NUTDEVICE *) dev->dev_icb; break; case HDLC_SETTXACCM: dcb->dcb_tx_accm = *((uint32_t *) conf); break; case HDLC_GETTXACCM: *((uint32_t *) conf) = dcb->dcb_tx_accm; break; default: rc = _ioctl(((PPPHDLC_DCB *) (dev->dev_dcb))->dcb_fd, req, conf); break; } return rc; } /*! * \brief Initialize asynchronous HDLC device. * * This function will be called during device registration. * * \param dev Identifies the device to initialize. * * \return 0 on success, -1 otherwise. */ static int PppHdlcInit(NUTDEVICE * dev) { return 0; } /*! * \brief Open the asynchronous HDLC device. * * This function is called internally when opening the PPP driver and * will in turn open the physical UART device. Therefore it is required, * that the UART driver has been registered before opening the PPP device. * * \param dev Pointer to the \ref NUTDEVICE structure. * \param name Ignored, should point to an empty string. * \param mode Operation mode, should be set to \ref _O_RDWR or-ed with * \ref _O_BINARY. * \param acc Ignored, should be zero. * * \return Pointer to a NUTFILE structure if successful or NUTFILE_EOF otherwise. */ static NUTFILE *PppHdlcOpen(NUTDEVICE * dev, const char *name, int mode, int acc) { PPPHDLC_DCB *dcb; NUTFILE *nfp; dcb = (PPPHDLC_DCB *) dev->dev_dcb; /* Open the physical device. */ dcb->dcb_fd = _open(dev->dev_name + 1, mode); if (dcb->dcb_fd == -1) { return NUTFILE_EOF; } /* Set transmit ACCM prior to negotiation. */ dcb->dcb_tx_accm = 0xffffffff; /* Allocate a file structure to return. */ nfp = calloc(1, sizeof(*nfp)); if (nfp == NULL) { return NUTFILE_EOF; } nfp->nf_dev = dev; return nfp; } /*! * \brief Close the asynchronous HDLC device. * * This function is called internally when closing the PPP driver. It * will detach the network interface and close the UART device driver. * * \param nfp Pointer to a _NUTFILE structure, obtained by a previous call * to PppHdlcOpen(). * * \return 0 on success or -1 otherwise. */ static int PppHdlcClose(NUTFILE * nfp) { int rc; PppHdlcAttach(nfp->nf_dev, NULL); rc = _close(((PPPHDLC_DCB *) (nfp->nf_dev->dev_dcb))->dcb_fd); free(nfp); return rc; } /*! * \brief Read raw data from the asynchronous HDLC device. * * This call is simply passed to the UART driver. * * \param nfp Pointer to a \ref _NUTFILE structure, obtained by a * previous call to PppHdlcOpen(). * \param buffer Pointer to the buffer that receives the data. * \param size Maximum number of bytes to read. * * \return The number of bytes read, which may be less than the number * of bytes specified. A return value of -1 indicates an error, * while zero is returned in case of a timeout. */ static int PppHdlcRead(NUTFILE *nfp, void *buffer, int size) { return _read(((PPPHDLC_DCB *) (nfp->nf_dev->dev_dcb))->dcb_fd, buffer, size); } /*! * \brief Write raw data to the asynchronous HDLC device. * * This call is simply passed to the UART driver. * * \param nfp Pointer to a \ref _NUTFILE structure, obtained by a * previous call to PppHdlcOpen(). * \param buffer Pointer the data to write. * \param len Number of data bytes to write. * * \return The number of bytes written, which may be less than the number * of bytes specified if a timeout occured. A return value of -1 * indicates an error. */ static int PppHdlcWrite(NUTFILE *nfp, const void *buffer, int len) { return _write(((PPPHDLC_DCB *) (nfp->nf_dev->dev_dcb))->dcb_fd, buffer, len); } NUTDEVICE devPppHdlc0 = { NULL, /* Pointer to next device, dev_next. */ { 'l', 'u', 'a', 'r', 't', '0', 0, 0, 0 }, /* Hardware device name, dev_name. */ IFTYP_CHAR, /* Type of device, dev_type. */ 0, /* Base address, dev_base (not used). */ 0, /* First interrupt number, dev_irq (not used). */ NULL, /* Interface control block, dev_icb. */ &dcb_ppp0, /* Driver control block, dev_dcb. */ PppHdlcInit, /* Driver initialization routine, dev_init. */ PppHdlcIoCtl, /* Driver specific control function, dev_ioctl. */ PppHdlcRead, /* Read from device, dev_read. */ PppHdlcWrite, /* Write to device, dev_write. */ #ifdef __HARVARD_ARCH__ NULL, /* Write data from program space to device, dev_write_P. */ #endif PppHdlcOpen, /* Open a device or file, dev_open. */ PppHdlcClose, /* Close a device or file, dev_close. */ NULL, /* Request file size, dev_size. */ NULL, /* Select function, optional, not yet implemented */ }; NUTDEVICE devPppHdlc1 = { NULL, /* Pointer to next device, dev_next. */ { 'l', 'u', 'a', 'r', 't', '1', 0, 0, 0 }, /* Hardware device name, dev_name. */ IFTYP_CHAR, /* Type of device, dev_type. */ 0, /* Base address, dev_base (not used). */ 0, /* First interrupt number, dev_irq (not used). */ NULL, /* Interface control block, dev_icb. */ &dcb_ppp1, /* Driver control block, dev_dcb. */ PppHdlcInit, /* Driver initialization routine, dev_init. */ PppHdlcIoCtl, /* Driver specific control function, dev_ioctl. */ PppHdlcRead, /* Read from device, dev_read. */ PppHdlcWrite, /* Write to device, dev_write. */ #ifdef __HARVARD_ARCH__ NULL, /* Write data from program space to device, dev_write_P. */ #endif PppHdlcOpen, /* Open a device or file, dev_open. */ PppHdlcClose, /* Close a device or file, dev_close. */ NULL, /* Request file size, dev_size. */ NULL, /* Select function, optional, not yet implemented */ };