HelenOS sources

root/uspace/lib/pcap/src/pcapdump_client.c

DEFINITIONS

1. pcapctl_dump_exchange_end
2. pcapctl_cat_get_svc
3. pcapctl_is_valid_device
4. pcapctl_is_valid_ops_number
5. pcapctl_list
6. pcapctl_dump_open
7. pcapctl_dump_close
8. pcapctl_dump_start
9. pcapctl_dump_stop

/*
 * Copyright (c) 2023 Nataliia Korop
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - 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.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */

/** @addtogroup libpcap
 * @{
 */
/** @file Client side of the pcapctl. Functions are called from the app pcapctl.
 */

#include <errno.h>
#include <async.h>
#include <str.h>
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
#include "pcapdump_client.h"
#include "pcapdump_ipc.h"

/** Finish an async exchange on the pcapctl session
 *
 * @param exch  Exchange to be finished
 */
static void pcapctl_dump_exchange_end(async_exch_t *exch)
{
        async_exchange_end(exch);
}

/** Get service based on the index of the device.
 *  @param index of the device.
 *  @param svc placeholder for service ide.
 *  @return EOK if successful, error code otherwise.
 */
static errno_t pcapctl_cat_get_svc(int *index, service_id_t *svc)
{
        errno_t rc;
        category_id_t pcap_cat;
        size_t count;
        service_id_t *pcap_svcs = NULL;

        rc = loc_category_get_id("pcap", &pcap_cat, 0);
        if (rc != EOK) {
                fprintf(stderr, "Error resolving category 'pcap'.\n");
                return rc;
        }

        rc = loc_category_get_svcs(pcap_cat, &pcap_svcs, &count);
        if (rc != EOK) {
                fprintf(stderr, "Error resolving list of pcap services.\n");
                free(pcap_svcs);
                return rc;
        }
        if (*index < (int)count) {
                *svc =  pcap_svcs[*index];
                free(pcap_svcs);
                return EOK;
        }

        return ENOENT;
}

/** Check if the index is an index of valid device.
 *  @param index to check.
 *  @return EOK if device is valid, error code otherwise.
 */
errno_t pcapctl_is_valid_device(int *index)
{
        errno_t rc;
        category_id_t pcap_cat;
        size_t count;
        service_id_t *pcap_svcs = NULL;

        rc = loc_category_get_id("pcap", &pcap_cat, 0);
        if (rc != EOK) {
                fprintf(stderr, "Error resolving category pcap.\n");
                return rc;
        }

        rc = loc_category_get_svcs(pcap_cat, &pcap_svcs, &count);
        if (rc != EOK) {
                fprintf(stderr, "Error resolving list of pcap services.\n");
                free(pcap_svcs);
                return rc;
        }
        if (*index + 1 > (int)count || *index < 0) {
                return EINVAL;
        }
        return EOK;
}

/** Check if the index is an index of valid writer operations.
 * @param index to check.
 * @param sess  pcapctl session for IPC communictaion.
 */
errno_t pcapctl_is_valid_ops_number(int *index, pcapctl_sess_t *sess)
{
        async_exch_t *exch = async_exchange_begin(sess->sess);
        ipc_call_t answer;
        aid_t req = async_send_0(exch, PCAP_CONTROL_GET_OPS_NUM, &answer);

        async_exchange_end(exch);

        errno_t retval;
        async_wait_for(req, &retval);

        if (retval != EOK) {
                return retval;
        }

        int ops_count = (int)ipc_get_arg1(&answer);
        if (*index + 1 > ops_count || *index < 0) {
                return EINVAL;
        }
        return EOK;
}

/** Get all devices that can dump packets. */
errno_t pcapctl_list(void)
{
        errno_t rc;
        category_id_t pcap_cat;
        size_t count;
        service_id_t *pcap_svcs = NULL;

        rc = loc_category_get_id("pcap", &pcap_cat, 0);
        if (rc != EOK) {
                fprintf(stderr, "Error resolving category pcap.\n");
                return rc;
        }

        rc = loc_category_get_svcs(pcap_cat, &pcap_svcs, &count);
        if (rc != EOK) {
                fprintf(stderr, "Error resolving list of pcap services.\n");
                free(pcap_svcs);
                return rc;
        }

        fprintf(stdout, "Devices:\n");
        for (unsigned i = 0; i < count; ++i) {
                char *name = NULL;
                loc_service_get_name(pcap_svcs[i], &name);
                fprintf(stdout, "%d. %s\n", i, name);
        }
        free(pcap_svcs);
        return EOK;
}

/** Start pcapctl IPC session.
 *  @param index        index of the device which can dump packets.
 *  @param rsess        placeholder for the session.
 *  @return                     EOK if successful, error code otherwise.
 */
errno_t pcapctl_dump_open(int *index, pcapctl_sess_t **rsess)
{
        errno_t rc;
        service_id_t svc;
        pcapctl_sess_t *sess = calloc(1, sizeof(pcapctl_sess_t));
        if (sess == NULL)
                return ENOMEM;

        if (*index == -1) {
                *index = 0;
        }

        rc  = pcapctl_cat_get_svc(index, &svc);
        if (rc != EOK) {
                fprintf(stderr, "Error finding the device with index: %d\n", *index);
                goto error;
        }

        async_sess_t *new_session = loc_service_connect(svc, INTERFACE_PCAP_CONTROL, 0);
        if (new_session == NULL) {
                fprintf(stderr, "Error connecting to service.\n");
                rc =  EREFUSED;
                goto error;
        }

        sess->sess = new_session;
        *rsess = sess;
        return EOK;
error:
        pcapctl_dump_close(sess);
        return rc;
}

/** Close pcapctl IPC session.
 *  @param sess Session to close.
 *  @return EOK if successful, error code otherwise.
 */
errno_t pcapctl_dump_close(pcapctl_sess_t *sess)
{
        free(sess);
        return EOK;
}

/** Send start request via IPC to start dumping.
 *
 * @param name  Name of the destination buffer to dump packets to.
 * @param sess  Session that is used for communication.
 * @return              EOK on success or an error code.
 */
errno_t pcapctl_dump_start(const char *name, int *ops_index, pcapctl_sess_t *sess)
{
        errno_t rc;
        async_exch_t *exch = async_exchange_begin(sess->sess);

        size_t size = str_size(name);
        aid_t req = async_send_1(exch, PCAP_CONTROL_SET_START, *ops_index, NULL);

        rc = async_data_write_start(exch, name, size);

        pcapctl_dump_exchange_end(exch);

        if (rc != EOK) {
                async_forget(req);
                return rc;
        }

        errno_t retval;
        async_wait_for(req, &retval);
        return retval;
}

/** Send stop request via IPC to start dumping.
 *
 * @param sess  Session that is used for communication.
 * @return              EOK on success or an error code.
 */
errno_t pcapctl_dump_stop(pcapctl_sess_t *sess)
{
        errno_t rc;
        async_exch_t *exch = async_exchange_begin(sess->sess);
        rc = async_req_0_0(exch, PCAP_CONTROL_SET_STOP);

        pcapctl_dump_exchange_end(exch);
        return rc;
}

/** @}
 */