/*
 * reader-openct.c: backend for OpenCT
 *
 * Copyright (C) 2003  Olaf Kirch <okir@suse.de>
 */

#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/un.h>
#include <unistd.h>

#include <openct/openct.h>
#include <openct/logging.h>
#include <openct/error.h>

#include "opensc.h"
#include "internal.h"
#include "log.h"

/* If you set PREALLOCATE to a non-zero value, this backend
 * will allocate that many reader slots. This will allow hot-
 * plugging devices (such as USB tokens) while OpenSC is running.
 *
 * To disable this, set PREALLOCATE to 0.
 *
 * This will most likely become a config file option soon.
 */
#define PREALLOCATE	5

/* function declarations */
static int openct_reader_init(struct sc_context *ctx, void **priv_data);
static int openct_add_reader(struct sc_context *ctx, unsigned int num, ct_info_t *info);
static int openct_reader_finish(struct sc_context *ctx, void *priv_data);
static int openct_reader_release(struct sc_reader *reader);
static int openct_reader_detect_card_presence(struct sc_reader *reader,
			struct sc_slot_info *slot);
static int openct_reader_connect(struct sc_reader *reader,
			struct sc_slot_info *slot);
static int openct_reader_disconnect(struct sc_reader *reader,
			struct sc_slot_info *slot, int action);
static int openct_reader_transmit(struct sc_reader *reader,
			struct sc_slot_info *slot,
			const u8 *sendbuf, size_t sendsize,
			u8 *recvbuf, size_t *recvsize, int control);
static int openct_reader_lock(struct sc_reader *reader,
			struct sc_slot_info *slot);
static int openct_reader_unlock(struct sc_reader *reader,
			struct sc_slot_info *slot);
static int		openct_error(struct sc_reader *, int);

/* the operations struct, already initialized */
static struct sc_reader_operations openct_reader_operations = {
	.init			= openct_reader_init,
	.finish			= openct_reader_finish,
	.release		= openct_reader_release,
	.detect_card_presence	= openct_reader_detect_card_presence,
	.connect		= openct_reader_connect,
	.disconnect		= openct_reader_disconnect,
	.transmit		= openct_reader_transmit,
	.lock			= openct_reader_lock,
	.unlock			= openct_reader_unlock,
};

/* also, the driver struct */
static struct sc_reader_driver openct_reader_driver = {
	.name = "OpenCT Reader",
	.short_name = "openct",
	.ops = &openct_reader_operations
};

/* return our structure */
const struct sc_reader_driver *sc_get_openct_driver() {
	return &openct_reader_driver;
};

/* private data structures */
struct driver_data {
	ct_handle *	h;
	unsigned int	num;
	ct_info_t	info;
};

struct slot_data {
	ct_lock_handle	excl_lock;
	ct_lock_handle	shared_lock;
};

/*
 * Initialize readers
 *
 * Called during sc_establish_context(), when the driver
 * is loaded
 */
static int
openct_reader_init(struct sc_context *ctx, void **priv_data)
{
	unsigned int	i;

	SC_FUNC_CALLED(ctx, 1);
	for (i = 0; i < OPENCT_MAX_READERS; i++) {
		ct_info_t	info;

		if (ct_reader_info(i, &info) >= 0) {
			openct_add_reader(ctx, i, &info);
		} else if (i < PREALLOCATE) {
			openct_add_reader(ctx, i, NULL);
		}
	}

	return SC_NO_ERROR;
}

static int
openct_add_reader(struct sc_context *ctx, unsigned int num, ct_info_t *info)
{
	sc_reader_t	*reader;
	struct driver_data *data;
	int		rc, i;

	if (!(reader = calloc(1, sizeof(*reader)))
	 || !(data = (calloc(1, sizeof(*data))))) {
		if (reader)
			free(reader);
		return SC_ERROR_OUT_OF_MEMORY;
	}

	if (info) {
		data->info = *info;
	} else {
		strcpy(data->info.ct_name, "OpenCT reader (detached)");
		data->info.ct_slots = 1;
	}
	data->num = num;

	reader->driver = &openct_reader_driver;
	reader->ops = &openct_reader_operations;
	reader->drv_data = data;
	reader->name = strdup(data->info.ct_name);
	reader->slot_count = data->info.ct_slots;

	if ((rc = _sc_add_reader(ctx, reader)) < 0) { 
		free(data);
		free(reader->name);
		free(reader);
		return rc;
	}

	for (i = 0; i < SC_MAX_SLOTS; i++) {
		reader->slot[i].drv_data = calloc(1, sizeof(struct slot_data));
		reader->slot[i].id = i;
	}

	return 0;
}

/*
 * Called when the driver is being unloaded.  finish() has to
 * deallocate the private data and any resources.
 */
int
openct_reader_finish(struct sc_context *ctx, void *priv_data)
{
	SC_FUNC_CALLED(ctx, 1);
	return SC_NO_ERROR;
}

/*
 * Called when releasing a reader.  release() has to
 * deallocate the private data.  Other fields will be
 * freed by OpenSC.
 */
int
openct_reader_release(struct sc_reader *reader)
{
	struct driver_data *data = (struct driver_data *) reader->drv_data;

	SC_FUNC_CALLED(reader->ctx, 1);
	if (data) {
		if (data->h)
			ct_reader_disconnect(data->h);
		memset(data, 0, sizeof(*data));
		reader->drv_data = NULL;
		free(data);
	}
	
	return SC_NO_ERROR;
}

/*
 * Check whether a card was added/removed
 */
int
openct_reader_detect_card_presence(struct sc_reader *reader,
			struct sc_slot_info *slot)
{
	struct driver_data *data = (struct driver_data *) reader->drv_data;
	int rc, status;

	SC_FUNC_CALLED(reader->ctx, 1);

	if (!data->h && !(data->h = ct_reader_connect(data->num)))
		return SC_ERROR_CARD_NOT_PRESENT;

	if ((rc = ct_card_status(data->h, slot->id, &status)) < 0)
		return SC_ERROR_TRANSMIT_FAILED;

	if (status & IFD_CARD_PRESENT) {
		slot->flags = SC_SLOT_CARD_PRESENT;
		if (status & IFD_CARD_STATUS_CHANGED)
			slot->flags = SC_SLOT_CARD_PRESENT;
	}
	return slot->flags;
}

static int
openct_reader_connect(struct sc_reader *reader,
			struct sc_slot_info *slot)
{
	struct driver_data *data = (struct driver_data *) reader->drv_data;
	int rc;

	SC_FUNC_CALLED(reader->ctx, 1);

	if (data->h)
		ct_reader_disconnect(data->h);

	if (!(data->h = ct_reader_connect(data->num))) {
		error(reader->ctx, "ct_reader_connect socket failed\n");
		return SC_ERROR_CARD_NOT_PRESENT;
	}

	rc = ct_card_request(data->h, slot->id, 0, NULL,
				slot->atr, sizeof(slot->atr));
	if (rc < 0) {
		error(reader->ctx,
				"openct_reader_connect read failed: %s\n",
				ct_strerror(rc));
		return SC_ERROR_CARD_NOT_PRESENT;
	}

	if (rc == 0) {
		error(reader->ctx, "openct_reader_connect recved no data\n");
		return SC_ERROR_READER;
	}

	slot->atr_len = rc;
	return SC_NO_ERROR;
}

static int
openct_reader_reconnect(struct sc_reader *reader,
			struct sc_slot_info *slot)
{
	struct driver_data *data = (struct driver_data *) reader->drv_data;
	int	rc;

	if (data->h != NULL)
		return 0;

	if ((rc = openct_reader_connect(reader, slot)) < 0)
		return SC_ERROR_READER_DETACHED;
	return SC_ERROR_READER_REATTACHED;
}

int
openct_reader_disconnect(struct sc_reader *reader,
			struct sc_slot_info *slot, int action)
{
	struct driver_data *data = (struct driver_data *) reader->drv_data;

	SC_FUNC_CALLED(reader->ctx, 1);
	if (data->h)
		ct_reader_disconnect(data->h);
	data->h = NULL;
	return SC_NO_ERROR;
}

int
openct_reader_transmit(struct sc_reader *reader,
		struct sc_slot_info *slot,
		const u8 *sendbuf, size_t sendsize,
		u8 *recvbuf, size_t *recvsize, int control)
{
	struct driver_data *data = (struct driver_data *) reader->drv_data;
	int rc;

	SC_FUNC_CALLED(reader->ctx, 1);

	/* Hotplug check */
	if ((rc = openct_reader_reconnect(reader, slot)) < 0)
		return rc;

	rc = ct_card_transact(data->h, slot->id,
			sendbuf, sendsize,
			recvbuf, *recvsize);

	if (rc == IFD_ERROR_NOT_CONNECTED) {
		ct_reader_disconnect(data->h);
		data->h = NULL;
		return SC_ERROR_READER_DETACHED;
	}

	if (rc >= 0)
		*recvsize = rc;

	return openct_error(reader, rc);
}

int
openct_reader_lock(struct sc_reader *reader,
			struct sc_slot_info *slot)
{
	struct driver_data *data = (struct driver_data *) reader->drv_data;
	struct slot_data *slot_data = (struct slot_data *) slot->drv_data;
	int rc, retry = 1;

	SC_FUNC_CALLED(reader->ctx, 1);

	/* Hotplug check */
	if ((rc = openct_reader_reconnect(reader, slot)) < 0)
		return rc;

	rc = ct_card_lock(data->h, slot->id,
				IFD_LOCK_EXCLUSIVE,
				&slot_data->excl_lock);

	if (rc == IFD_ERROR_NOT_CONNECTED) {
		ct_reader_disconnect(data->h);
		data->h = NULL;
		return SC_ERROR_READER_DETACHED;
	}

	return openct_error(reader, rc);
}

int
openct_reader_unlock(struct sc_reader *reader,
			struct sc_slot_info *slot)
{
	struct driver_data *data = (struct driver_data *) reader->drv_data;
	struct slot_data *slot_data = (struct slot_data *) slot->drv_data;
	int rc;

	SC_FUNC_CALLED(reader->ctx, 1);

	rc = ct_card_unlock(data->h, slot->id, slot_data->excl_lock);

	/* We couldn't care less */
	if (rc == IFD_ERROR_NOT_CONNECTED)
		return 0;

	return openct_error(reader, rc);
}

/*
 * Handle an error code returned by OpenCT
 */
int
openct_error(struct sc_reader *reader, int code)
{
	if (code >= 0)
		return code;

	/* Fixme: translate error code */
	return SC_ERROR_READER;
}