path: root/utils/swi-update.c

/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * swi-update -- Command line tool to update QMI firmware
 *
 * 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.
 *
 * 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, see <http://www.gnu.org/licenses/>.
 *
 * Copyright (C) Copyright 2016 Bjørn Mork <bjorn@mork.no>
 *
 * crc16 and hdlc parts:
 *   Copyright (C) 2010 Red Hat, Inc.
 *
 * parts of this is based on gobi-loader, which is
 *
 *  "Copyright 2009 Red Hat <mjg@redhat.com> - heavily based on work done by
 *   Alexander Shumakovitch <shurik@gwu.edu>
 *
 *   Gobi 2000 support provided by Anssi Hannula <anssi.hannula@iki.fi>"
 */

#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <limits.h>
#include <linux/types.h>
#include <malloc.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <termios.h>
#include <unistd.h>

/* FIXME: endianness - this works on LE for now... */

#ifndef VERSION
  #define VERSION "unknown"
#endif
#define DESCRIPTION "swi-update (" VERSION ")"

#ifdef DEBUG
static bool debug;
#define debug(arg...) if (debug) fprintf(stderr, arg)
static void print_packet(const char *pfx, void *buf, int len)
{
	int i;
	unsigned char *p = buf;

	if (!debug)
		return;
	fprintf(stderr, "%s: ", pfx);
	for (i=0; i<len; i++)
		fprintf(stderr, "%02x ", p[i]);
	fprintf(stderr, "\n");
}
#else
#define debug(arg...)
#define print_packet(pfx, buf, len)
#endif /* DEBUG */


#define CHUNK (1024 * 1024)

/** DLOAD protocol **/

/*
 * Most of this is from Josuah Hill's DLOAD tool for iPhone
 * Some spec is also available in document 80-39912-1 Rev. E  DMSS Download Protocol Interface Specification and Operational Description
 * https://github.com/posixninja/DLOADTool/blob/master/dloadtool/dload.h
 *
 * The 0x70 switching command was found by snooping on firmware updates
 */

enum dload_cmd {
	DLOAD_ACK = 0x02, /* Acknowledge receiving a packet */
	DLOAD_NOP = 0x06, /* No operation, useful for debugging */
	DLOAD_SDP = 0x70, /* Switch to Streaming DLOAD */
};

/* 0x02 - __u8 cmd only */
/* 0x06 - __u8 cmd only */

struct dload_sdp {
	__u8 cmd; /* 0x70 */
	__u16 reserved; /* 0x0000 */
} __attribute__ ((packed));

static struct dload_sdp dload_sdp = {
	.cmd = 0x70,
	.reserved = 0,
};

/** Streaming DLOAD protocol **/

/* from GobiAPI_1.0.40/Core/QDLEnum.h and
 * GobiAPI_1.0.40/Core/QDLBuffers.h with additional details from USB
 * snooping
 */
enum qdl_cmd {
	QDL_CMD_HELLO_REQ	    = 0x01,	/* Hello request */
	QDL_CMD_HELLO_RSP,			/* Hello response */
	QDL_CMD_ERROR		    = 0x0d,	/* Error report */
	QDL_CMD_OPEN_UNFRAMED_REQ   = 0x25, /* Open unframed image write request */
	QDL_CMD_OPEN_UNFRAMED_RSP,		/* Open unframed image write response */
	QDL_CMD_WRITE_UNFRAMED_REQ,		/* Unframed image write request */
	QDL_CMD_WRITE_UNFRAMED_RSP,		/* Unframed image write response */
	QDL_CMD_SESSION_DONE_REQ,		/* Unframed session done request */
	QDL_CMD_SESSION_DONE_RSP,		/* Unframed session done response */
	QDL_CMD_DOWNLOAD_REQ,			/* Switch to download protocol request */
	QDL_CMD_SESSION_CLOSE_REQ   = 0x2d,	/* Close unframed session request */
	QDL_CMD_GET_IMAGE_PREF_REQ,		/* Get image preference request */
	QDL_CMD_GET_IMAGE_PREF_RSP,		/* Get image preference response */
};

enum qdl_error {
	QDL_ERROR_01 = 1,            // 01 Reserved
	QDL_ERROR_BAD_ADDR,          // 02 Invalid destination address
	QDL_ERROR_BAD_LEN,           // 03 Invalid length
	QDL_ERROR_BAD_PACKET,        // 04 Unexpected end of packet
	QDL_ERROR_BAD_CMD,           // 05 Invalid command
	QDL_ERROR_06,                // 06 Reserved
	QDL_ERROR_OP_FAILED,         // 07 Operation failed
	QDL_ERROR_BAD_FLASH_ID,      // 08 Invalid flash intelligent ID
	QDL_ERROR_BAD_VOLTAGE,       // 09 Invalid programming voltage
	QDL_ERROR_WRITE_FAILED,      // 10 Write verify failed
	QDL_ERROR_11,                // 11 Reserved
	QDL_ERROR_BAD_SPC,           // 12 Invalid security code
	QDL_ERROR_POWERDOWN,         // 13 Power-down failed
	QDL_ERROR_UNSUPPORTED,       // 14 NAND flash programming not supported
	QDL_ERROR_CMD_SEQ,           // 15 Command out of sequence
	QDL_ERROR_CLOSE,             // 16 Close failed
	QDL_ERROR_BAD_FEATURES,      // 17 Invalid feature bits
	QDL_ERROR_SPACE,             // 18 Out of space
	QDL_ERROR_BAD_SECURITY,      // 19 Invalid security mode
	QDL_ERROR_MULTI_UNSUPPORTED, // 20 Multi-image NAND not supported
	QDL_ERROR_POWEROFF,          // 21 Power-off command not supported
	QDL_ERROR_CMD_UNSUPPORTED,   // 22 Command not supported
	QDL_ERROR_BAD_CRC,           // 23 Invalid CRC
	QDL_ERROR_STATE,             // 24 Command received in invalid state
	QDL_ERROR_TIMEOUT,           // 25 Receive timeout
	QDL_ERROR_IMAGE_AUTH,        // 26 Image authentication error
};

/* most of these origin from GobiAPI_1.0.40/Core/QDLEnum.h
 *
 * The gobi-loader's snooped magic strings use types
 *   0x05 => "amss.mbn"
 *   0x06 => "apps.mbn"
 *   0x0d => "uqcn.mbn" (Gobi 2000 only)
 *  with no file header data
 *
 * The 0x80 type is snooped from the Sierra Wireless firmware
 * uploaders, using 400 bytes file header data
 */

enum qdl_type {
	QDL_IMAGE_AMSS_MODEM		= 0x05,		// 05 AMSS modem image
	QDL_IMAGE_AMSS_APPLICATION,			// 06 AMSS application image
	QDL_IMAGE_AMSS_UQCN		= 0x0d,		// 13 Provisioning information
	QDL_IMAGE_DBL			= 0x0f,		// 15 DBL image
	QDL_IMAGE_OSBL,					// 16 OSBL image
	QDL_IMAGE_CWE			= 0x80,		// 128 CWE image
};

static const char *qdl_type2str(__u8 type)
{
	switch (type) {
	case QDL_IMAGE_AMSS_MODEM:
		return "AMSS_MODEM";
	case QDL_IMAGE_AMSS_APPLICATION:
		return "AMSS_APPLICATION";
	case QDL_IMAGE_AMSS_UQCN:
		return "AMSS_UQCN";
	case QDL_IMAGE_DBL:
		return "DBL";
	case QDL_IMAGE_OSBL:
		return "OSBL";
	case QDL_IMAGE_CWE:
		return "CWE";
	default:
		return "UNKNOWN";
	}
}

/* feature bits */
#define QDL_FEATURE_GENERIC_UNFRAMED	0x10
#define QDL_FEATURE_QDL_UNFRAMED	0x20
#define QDL_FEATURE_BAR_MODE		0x40

struct qdl_hello_req {
	__u8 cmd; /* 0x01 */
	char magic[32];
	__u8 maxver;
	__u8 minver;
	__u8 features;
}  __attribute__ ((packed));

static struct qdl_hello_req qdl_hello_req = {
	.cmd = QDL_CMD_HELLO_REQ,
	.magic = { 'Q', 'C', 'O', 'M', ' ', 'h', 'i', 'g', 'h', ' ', 's', 'p', 'e', 'e', 'd', ' ', 'p', 'r', 'o', 't', 'o', 'c', 'o', 'l', ' ', 'h', 's', 't', },
	.maxver = 0,
	.minver = 0,
	.features = QDL_FEATURE_QDL_UNFRAMED | QDL_FEATURE_GENERIC_UNFRAMED,
};

struct qdl_hello_rsp {
	__u8 cmd; /* 0x02 */
	char magic[32];
	__u8 maxver;
	__u8 minver;
	__u32 reserved1;
	__u32 reserved2;
	__u8 reserved3;
	__u16 reserved4;
	__u16 reserved5;
	__u8 features;
}  __attribute__ ((packed));

struct qdl_err_rsp {
	__u8 cmd; /* 0x0d */
	__u32 error;
	__u8 errortxt;
}  __attribute__ ((packed));

struct qdl_ufopen_req {
	__u8 cmd; /* 0x25 */
	__u8 type;
	__u32 length;
	__u8 windowsize;
	__u32 chunksize;
	__u16 reserved;
	/* The first 400 bytes of the image is appended to the "open
	 * unframed" request on Sierra Wireless modems.  This chunk is
	 * not included here as it is not a part of the request.
	 *
	 * The file header inclusion here seems to depend on the file
	 * type
	 */
}  __attribute__ ((packed));

struct qdl_ufopen_rsp {
	__u8 cmd; /* 0x26 */
	__u16 status;
	__u8 windowsize;
	__u32 chunksize;
}  __attribute__ ((packed));

/* This request is not HDLC framed, so this "header" includes the crc */
struct qdl_ufwrite_req {
	__u8 cmd; /* 0x27 */
	__u16 sequence;
	__u32 reserved;
	__u32 chunksize;
	__u16 crc;
}  __attribute__ ((packed));

/* the buffer most hold a file chunk + this header */
#define BUFSIZE (CHUNK + sizeof(struct qdl_ufwrite_req))

/* The response is HDLC framed, so the crc is part of the framing */
struct qdl_ufwrite_rsp {
	__u8 cmd; /* 0x28 */
	__u16 sequence;
	__u32 reserved;
	__u16 status;
}  __attribute__ ((packed));

/* __u8 0x29 - cmd only */

struct qdl_ufclose_rsp {
	__u8 cmd; /* 0x2a */
	__u16 status;
	__u8 type;
	__u8 errortxt;
}  __attribute__ ((packed));

/* __u8 0x2d - cmd only */
/* __u8 0x2e - cmd only */

struct qdl_imagepref_rsp {
	__u8 cmd; /* 0x2f */
	__u8 entries;
	struct {
		__u8 type;
		char id[16];
	} image[];
}  __attribute__ ((packed));

/*
 * crc16 and HDLC escape code borrowed from modemmanager/libqcdm
 * Copyright (C) 2010 Red Hat, Inc.
 */

/* Table of CRCs for each possible byte, with a generator polynomial of 0x8408 */
static const __u16 crc_table[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 the CRC for a buffer using a seed of 0xffff */
static __u16 crc16(const char *buffer, size_t len)
{
    __u16 crc = 0xffff;

    while (len--)
            crc = crc_table[(crc ^ *buffer++) & 0xff] ^ (crc >> 8);
    return ~crc;
}

#define CONTROL 0x7e
#define ESCAPE  0x7d
#define MASK    0x20

static size_t escape(const char *in, size_t inlen, char *out, size_t outlen)
{
	size_t i, j;

	for (i = 0, j = 0; i < inlen; i++) {
		if (in[i] == CONTROL || in[i] == ESCAPE) {
			out[j++] = ESCAPE;
			if (j < outlen)
				out[j++] = in[i] ^ MASK;
		} else {
			out[j++] = in[i];
		}
		if (j >= outlen)
			return 0; /* failed to enscape -  buffer too small */
	}
	return j;
}

static size_t unescape(const char *in, size_t inlen, char *out, size_t outlen)
{
	size_t i, j = 0;
	bool escaping = false;

	for (i = 0; i < inlen; i++) {
		if (j >= outlen) {
			debug("i=%zu, j=%zu, inlen=%zu, outlen=%zu\n", i, j, inlen, outlen);
			return 0;
		}
		if (escaping) {
			out[j++] = in[i] ^ MASK;
			escaping = false;
		} else if (in[i] == ESCAPE) {
			escaping = true;
		} else {
			out[j++] = in[i];
		}
	}
	return j;
}

/* copy a possibly escaped single byte to out */
static size_t escape_byte(__u8 byte, char *out, size_t outlen)
{
	size_t j = 0;

	if (byte == CONTROL || byte == ESCAPE) {
		out[j++] = ESCAPE;
		byte ^= MASK;
	}
	out[j++] = byte;
	return j;
}

static size_t hdlc_frame(const char *in, size_t inlen, char *out, size_t outlen)
{
    __u16 crc;
    size_t j = 0;

    out[j++] = CONTROL;
    j += escape(in, inlen, &out[j], outlen - j);
    crc = crc16(in, inlen);
    j += escape_byte(crc & 0xff, &out[j], outlen - j);
    j += escape_byte(crc >> 8 & 0xff, &out[j], outlen - j);
    out[j++] = CONTROL;

    if (j < inlen)
	    return 0;    /* FIXME */

    return j;
}

static size_t hdlc_unframe(const char *in, size_t inlen, char *out, size_t outlen)
{
    __u16 crc;
    size_t j, i = inlen;

    /* the first control char is optional */
    if (*in == CONTROL) {
	    in++;
	    i--;
    }
    if (in[i - 1] == CONTROL)
	    i--;

    j = unescape(in, i, out, outlen);
    if (j < 2) {
	    debug("unescape failed: j = %zu\n", j);
	    return 0;
    }
    j -= 2; /* remove the crc */

    /* verify the crc */
    crc = crc16(out, j);
    if (crc != ((unsigned char)out[j] | (unsigned char)out[j + 1] << 8)) {
	    debug("crc failed: 0x%04x != 0x%04x\n", crc, out[j] | out[j + 1] << 8);
	    return 0;
    }
    return j;
}

/* should the unframed open request include a file header? */
static inline size_t hdrlen(__u8 type)
{
	switch (type) {
	case QDL_IMAGE_CWE:
		return 400;
	default:
		return 0;
	}
}

/* some image types contain trailing garbage - from gobi-loader */
static inline size_t imglen(__u8 type, size_t len)
{
	switch (type) {
	case QDL_IMAGE_AMSS_MODEM:
		return len - 8;
	default:
		return len;
	}
}

static size_t create_ufopen_req(char *in, size_t filelen, __u8 type)
{
	struct qdl_ufopen_req *req = (void *)in;

	req->cmd = QDL_CMD_OPEN_UNFRAMED_REQ;
	req->type = type;
	req ->windowsize = 1; /* snooped */
	req->length = imglen(type, filelen);
	req->chunksize = imglen(type, filelen) - hdrlen(type);
	return sizeof(struct qdl_ufopen_req);
}

static size_t create_ufwrite_req(char *out, size_t chunksize, int sequence)
{
	struct qdl_ufwrite_req *req = (void *)out;

	req->cmd = QDL_CMD_WRITE_UNFRAMED_REQ;
	req->sequence = sequence;
	req->reserved = 0;
	req->chunksize = chunksize;
	req->crc = crc16(out, sizeof(*req) - 2);
	return sizeof(*req);
}

static int parse_sdp_hello(const char *in, size_t inlen)
{
	struct qdl_hello_rsp *r;
	char buf[sizeof(*r) + sizeof(__u16)];
	char magicbuf[33] = {0};
	size_t ret;

	r = (struct qdl_hello_rsp *)buf;
	ret = hdlc_unframe(in, inlen, buf, sizeof(buf));
	if (ret == sizeof(*r) && r->cmd == QDL_CMD_HELLO_RSP) {
		memcpy(magicbuf, r->magic, r->maxver <= 5 ? 24 : 32);
		debug("magic: '%s'\nmaxver: %u\nminver: %u\nfeatures: 0x%02x\n", magicbuf, r->maxver, r->minver, r->features);
		return 0;
	}
	return -1; /* unexpected error */
}

static const char *sdperr2str(__u32 err)
{
	switch (err) {
	case QDL_ERROR_01:
		return "Reserved";
	case QDL_ERROR_BAD_ADDR:
		return "Invalid destination address";
	case QDL_ERROR_BAD_LEN:
		return "Invalid length";
	case QDL_ERROR_BAD_PACKET:
		return "Unexpected end of packet";
	case QDL_ERROR_BAD_CMD:
		return "Invalid command";
	case QDL_ERROR_06:
		return "Reserved";
	case QDL_ERROR_OP_FAILED:
		return "Operation failed";
	case QDL_ERROR_BAD_FLASH_ID:
		return "Invalid flash intelligent ID";
	case QDL_ERROR_BAD_VOLTAGE:
		return "Invalid programming voltage";
	case QDL_ERROR_WRITE_FAILED:
		return "Write verify failed";
	case QDL_ERROR_11:
		return "Reserved";
	case QDL_ERROR_BAD_SPC:
		return "Invalid security code";
	case QDL_ERROR_POWERDOWN:
		return "Power-down failed";
	case QDL_ERROR_UNSUPPORTED:
		return "NAND flash programming not supported";
	case QDL_ERROR_CMD_SEQ:
		return "Command out of sequence";
	case QDL_ERROR_CLOSE:
		return "Close failed";
	case QDL_ERROR_BAD_FEATURES:
		return "Invalid feature bits";
	case QDL_ERROR_SPACE:
		return "Out of space";
	case QDL_ERROR_BAD_SECURITY:
		return "Invalid security mode";
	case QDL_ERROR_MULTI_UNSUPPORTED:
		return "Multi-image NAND not supported";
	case QDL_ERROR_POWEROFF:
		return "Power-off command not supported";
	case QDL_ERROR_CMD_UNSUPPORTED:
		return "Command not supported";
	case QDL_ERROR_BAD_CRC:
		return "Invalid CRC";
	case QDL_ERROR_STATE:
		return "Command received in invalid state";
	case QDL_ERROR_TIMEOUT:
		return "Receive timeout";
	case QDL_ERROR_IMAGE_AUTH:
		return "Image authentication error";
	default:
		return "Unknown error";
	}
}

static int parse_sdp_err(const char *in, size_t inlen, bool silent)
{
	struct qdl_err_rsp *r;
	char buf[sizeof(*r) + sizeof(__u16)];
	size_t ret;

	r = (struct qdl_err_rsp *)buf;
	ret = hdlc_unframe(in, inlen, buf, sizeof(buf));
	if (ret == sizeof(*r) && r->cmd == QDL_CMD_ERROR) {
		if (!silent)
			fprintf(stderr, "SDP error %d (%d): %s\n", r->error, r->errortxt, sdperr2str(r->error));
		return -r->error;
	}
	return -1; /* not an proper error frame */
}

static int parse_ufopen(const char *in, size_t inlen)
{
	struct qdl_ufopen_rsp *r;
	char buf[sizeof(*r) + sizeof(__u16)];
	size_t ret;

	r = (struct qdl_ufopen_rsp *)buf;
	ret = hdlc_unframe(in, inlen, buf, sizeof(buf));
	if (ret != sizeof(*r) || r->cmd != QDL_CMD_OPEN_UNFRAMED_RSP)
		return -1;
	debug("status=%d, windowsize=%d, chunksize=%d\n", r->status, r->windowsize, r->chunksize);
	return -r->status;
}

static int parse_ufwrite(const char *in, size_t inlen)
{
	struct qdl_ufwrite_rsp *r;
	char buf[sizeof(*r) + sizeof(__u16)];
	size_t ret;

	r = (struct qdl_ufwrite_rsp *)buf;
	ret = hdlc_unframe(in, inlen, buf, sizeof(buf));
	if (ret != sizeof(*r) || r->cmd != QDL_CMD_WRITE_UNFRAMED_RSP)
		return -1;
	if (r->status) {
		fprintf(stderr, "seq 0x%04x status=%d\n", r->sequence, r->status);
		return -r->status;
	}
	debug("ack: %d\n", r->sequence);
	return r->sequence;
}

static int parse_ufdone(const char *in, size_t inlen)
{
	struct qdl_ufclose_rsp *r;
	char buf[sizeof(*r) + sizeof(__u16)];
	size_t ret;

	r = (struct qdl_ufclose_rsp *)buf;
	ret = hdlc_unframe(in, inlen, buf, sizeof(buf));
	if (ret != sizeof(*r) || r->cmd != QDL_CMD_SESSION_DONE_RSP)
		return -1;
	debug("UF close: status=%d, type=%d, errortxt=%d\n", r->status, r->type, r->errortxt);
	return -r->status;
}

/* read and parse QDL if available.  Will return unless data is
 * available withing 5 ms
 */
static int read_and_parse(int fd, bool silent)
{
	char *end, *p, rbuf[512];
	int rlen, framelen, ret = 0;
	fd_set rd;
	struct timeval tv = { .tv_sec = 1, .tv_usec = 0, };

	FD_ZERO(&rd);
	FD_SET(fd, &rd);
	if (select(fd + 1, &rd, NULL, NULL, &tv) <= 0) {
		debug("timeout: no data read\n");
		return 0;
	}

	rlen = read(fd, rbuf, sizeof(rbuf));
	if (rlen <= 0)
		return rlen;
	print_packet("read", rbuf, rlen);

	p = rbuf;
	while (rlen > 0 && (end = memchr(p + 1, CONTROL, rlen - 1)) != NULL) {
		end++;
		framelen = end - p;
		switch (p[1]) {
		case QDL_CMD_ERROR:
			ret = parse_sdp_err(p, framelen, silent);
			break;
		case QDL_CMD_HELLO_RSP: /* == DLOAD_ACK */
			if (framelen != 5)
				ret = parse_sdp_hello(p, framelen);
			else
				debug("Got DLOAD_ACK\n");
			break;
		case QDL_CMD_OPEN_UNFRAMED_RSP:
			ret = parse_ufopen(p, framelen);
			break;
		case QDL_CMD_WRITE_UNFRAMED_RSP:
			ret = parse_ufwrite(p, framelen);
			break;
		case QDL_CMD_SESSION_DONE_RSP:
			ret = parse_ufdone(p, framelen);
			break;
		default:
			fprintf(stderr, "Unsupported response code: 0x%02x\n", p[1]);
		}
		if (ret < 0)
			return ret;
		p = end;
		rlen -= framelen;
	}
	return ret;
}

static int write_hdlc(int fd, const char *in, size_t inlen)
{
	char wbuf[512];
	int wlen;

	wlen = hdlc_frame(in, inlen, wbuf, sizeof(wbuf));
	if (wlen > 0) {
		write(fd,  wbuf, wlen);
		print_packet("write", wbuf, wlen);
	} else {
		debug("hdlc_frame() returned %d\n", wlen);
	}
	return wlen;
}

static int serial_open(const char *dev)
{
	struct termios terminal_data;
	int fd;

	/* FIXME: verify that the serial device is a Sierra Wireless device in QDL mode */
	fd = open(dev,  O_RDWR | O_NOCTTY);
	if (fd > 0) {
		tcgetattr(fd, &terminal_data);
		cfmakeraw(&terminal_data);
		tcsetattr(fd, TCSANOW, &terminal_data);
	}
	debug("opened %s\n", dev);
	return fd;
}

/* Sierra Wireless CWE file header
 *   Note: 32bit numbers are big endian
 */
struct cwehdr {
	char reserved1[256];
	__u32 crc;		/* 32bit CRC of "reserved1" field */
	__u32 rev;		/* header revision */
	__u32 val;		/* CRC validity indicator */
	char type[4];		/* ASCII - not null terminated */
	char product[4];	/* ASCII - not null terminated */
	__u32 imgsize;		/* image size */
	__u32 imgcrc;		/* 32bit CRC of the image */
	char version[84];	/* ASCII - null terminated */
	char date[8];		/* ASCII - null terminated */
	__u32 compat;		/* backward compatibility */
	char reserved2[20];
};

static int verify_cwehdr(char *buf)
{
	struct cwehdr *h = (void *)buf;
	char tmp[5];

	fprintf(stderr, "  CWE revision: %d\n", be32toh(h->rev));
	memcpy(tmp, h->type, 4);
	tmp[4] = 0;
	fprintf(stderr, "  type: %s\n", tmp);
	memcpy(tmp, h->product, 4);
	tmp[4] = 0;
	fprintf(stderr, "  product: %s\n", tmp);
	fprintf(stderr, "  image size: %d\n", be32toh(h->imgsize));
	fprintf(stderr, "  version: %s\n", h->version);
	fprintf(stderr, "  date: %s\n", h->date);
	return 0;
}

/* guessing image type based on the well known Gobi 1k and 2k
 * filenames, and assumes anything else is a CWE image
 *
 * This is based on the types in gobi-loader's snooped magic strings:
 *   0x05 => "amss.mbn"
 *   0x06 => "apps.mbn"
 *   0x0d => "uqcn.mbn" (Gobi 2000 only)
 */
static __u8 filename2type(const char *filename)
{
	char *base = strrchr(filename, '/');

	if (!base)
		base = (char *)filename;
	if (!strcasecmp(base, "amss.mbn"))
		return QDL_IMAGE_AMSS_MODEM;
	if (!strcasecmp(base, "apps.mbn"))
		return QDL_IMAGE_AMSS_APPLICATION;
	if (!strcasecmp(base, "uqcn.mbn"))
		return QDL_IMAGE_AMSS_UQCN;
	return QDL_IMAGE_CWE;
}

static int download_image(int serfd, char *buf, const char *image)
{
	int imgfd = -1, ret = 0, seq = 0;
	size_t chunksize, rlen, filelen;
	struct stat img_data;
	__u8 type = filename2type(image);

	/* FIXME: verify that this image matches the modem */
	imgfd = open(image, O_RDONLY);
	if (imgfd < 0) {
		fprintf(stderr, "Cannot open %s: %d\n", image, imgfd);
		ret = imgfd;
		goto out;
	}
	fstat(imgfd, &img_data);
	filelen = imglen(type, img_data.st_size) - hdrlen(type);
	if (filelen < 0) {
		fprintf(stderr, "%s is too short\n", image);
		ret = -1;
		goto out;
	}

	fprintf(stderr, "Downloading %s image '%s'\n", qdl_type2str(type), image);

	/* send open request */
	rlen = create_ufopen_req(buf, img_data.st_size, type);
	if (hdrlen(type) > 0) {
		ret = -1;
		if (hdrlen(type) + rlen > BUFSIZE)
			goto out;
		if (read(imgfd, buf + rlen, hdrlen(type)) != hdrlen(type))
			goto out;
		if (type == QDL_IMAGE_CWE)
			verify_cwehdr(buf + rlen);
	}
	write_hdlc(serfd, buf, rlen + hdrlen(type));

	/* read ufopen response - FIXME: act on errors! */
	if (read_and_parse(serfd, false) < 0)
		goto out;

	/* remaining data to send */
	while (filelen > 0) {
		fd_set wr;
		struct timeval tv = { .tv_sec = 2, .tv_usec = 0, };

		chunksize = CHUNK;
		if (chunksize > filelen)
			chunksize = filelen;

		debug("write #%d (%zu)...", seq, chunksize);
		if (!debug)
			fprintf(stderr, ".");
		rlen = create_ufwrite_req(buf, chunksize, seq++);
		rlen += read(imgfd, buf + rlen, CHUNK);
		filelen -= chunksize;

		FD_ZERO(&wr);
		FD_SET(serfd, &wr);
		if (select(serfd + 1, NULL, &wr, NULL, &tv) <= 0)
			goto out;
		write(serfd,  buf, rlen);
		ret = read_and_parse(serfd, false);
		if (ret < 0)
			goto out;
	}

	debug("finished writing\n");

	/* This may take a considerable amount of time */
	fprintf(stderr, "\nWaiting for ack");
	while (ret != seq - 1) {
		fprintf(stderr, ".");
		sleep(3);
		ret = read_and_parse(serfd, false);
	}
	fprintf(stderr, "\n");

out:
	if (imgfd > 0)
		close(imgfd);
	return ret;
}

static struct option main_options[] = {
	{ "help",	0, 0, 'h' },
	{ "serial",     1, 0, 's' },
	{ "debug",      0, 0, 'd' },
	{ 0, 0, 0, 0 }
};

static void usage(const char *prog)
{
	fprintf(stderr,
		"\n%s: %s [ --help ]"
#ifdef DEBUG
		" [--debug] "
#endif
		"--serial <device> <image> [image2] [image3]\n",
		__func__, prog);
}

int main(int argc, char *argv[])
{
	int opt, serfd = -1, ret = 0, version;
	char *buffer = NULL;

	fprintf(stderr, "%s\n", DESCRIPTION);
	while ((opt = getopt_long(argc, argv, "i:s:m:dvh", main_options, NULL)) != -1) {
		switch(opt) {
		case 's':
			serfd = serial_open(optarg);
			break;
#ifdef DEBUG
		case 'd':
			debug = true;
			break;
#endif
		case 'h':
			usage(argv[0]);
			return 0;
		}
	}

	buffer = malloc(BUFSIZE);
	if (!buffer) {
		ret = -ENOMEM;
		goto err;
	}


/* FIXME: should do the following for a complete image upload*
 *
 *  For CWE images:
 *    - verify image sanity and retrive model/version data for next step if applicable
 *    - if application mode:
 *       + verify qmi model/version matching image
 *       + check usb sysfs (serial++) to match against bootloader mode
 *       + switch to bootloader mode
 *       + wait for QDL device to appear
 *
 * For all images:
 *    - verify that the QDL device is the correct one (check serial etc)
 *
 * NON WORKING:
 *    - allow multiple images to be uploaded in one run
 * How do we do this properly?
 */

	/* need at least one firmware filename */
	if (optind == argc) {
		usage(argv[0]);
		return -1;
	}

	if (serfd < 0)
		return serfd;

	/* switch to SDP - this is required for some modems like MC7710 */
	write_hdlc(serfd, (const char *)&dload_sdp, sizeof(dload_sdp));
	ret = read_and_parse(serfd, true);

	/* the modem could already be in SDP mode, so ignore "unsupported" errors */
	if (ret < 0 && ret != -QDL_ERROR_CMD_UNSUPPORTED)
		goto err;

	/* attempt to probe supported protocol version
	 *  Newer modems like Sierra Wireless MC7710 must use '6' for both fields
	 *  Gobi2000 modems like HP un2420 must use '5' for both fields
	 *  Gobi1000 modems  must use '4' for both fields
	 */
	for (version = 4; version < 7; version++) {
		qdl_hello_req.minver = version;
		qdl_hello_req.maxver = version;
		write_hdlc(serfd, (const char *)&qdl_hello_req, sizeof(qdl_hello_req));
		ret = read_and_parse(serfd, true);
		if (!ret)
			break;
	}
	if (ret < 0) {
		fprintf(stderr, "Unable to detect QDL version\n");
		goto err;
	}
	fprintf(stderr, "Got QDL version: %u\n", version);

	/* download all images */
	while (optind < argc && ret >= 0)
		ret = download_image(serfd, buffer, argv[optind++]);

	/* close unframed session */
	buffer[0] = QDL_CMD_SESSION_DONE_REQ;
	write_hdlc(serfd, buffer, 1);

	/* read close response  */
	if (!read_and_parse(serfd, false))
		fprintf(stderr, "Success!\n");

	/* terminate SDP session */
	fprintf(stderr, "Terminating session - rebooting modem...\n");
	buffer[0] = QDL_CMD_SESSION_CLOSE_REQ;
	write_hdlc(serfd, buffer, 1);

	/* no response? */
	read_and_parse(serfd, false);

err:
	if (serfd > 0)
		close(serfd);
	free(buffer);
	return ret;
}