qosmngr.c

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * qosmngr.c - main qosmngr's code
 *
 * Copyright (C) 2020 iopsys Software Solutions AB. All rights reserved.
 *
 * Author: Oskar Viljasaar <oskar.viljasaar@iopsys.eu>
 *
 * 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
 */

#include <libubox/blobmsg_json.h>
#include <libubus.h>
#include <uci.h>

/* Needed to get the IFNAMSIZ define */
#include <net/if.h>

#include "qosmngr.h"

/* Used as an internal value to query all the queues */
#define QOS_QUEUE_ANY	-1

/* Used for getting interface indexes for global q_stat array */
#define MIN_INDEX 48
#define MAX_INDEX 57

/* Used for fetching keys from ubus json reqest */
#define SEPERATOR 44
#define QUOTE	  34

/* Used to validate requested parameters */
#define PARAM1 "ifname"
#define PARAM2 "qid"

static int init_flag = 1;
static struct qos_stats **q_stat = {0};

/**
 *  get_no_queues function for getting number of queues on device by calling uci qos config
 *  @param ifname input parameter pointer to char for which number of queues needed
 *  retrun integer value 0 on success and -1 on failure
 */
static int get_no_queues(const char *ifname)
{
       int queues = 0;

       struct uci_package *uci_pkg = NULL;
       struct uci_element *uci_elmnt = NULL;
       struct uci_context *uci_ctx = uci_alloc_context();

       uci_load(uci_ctx, "qos", &uci_pkg);
       if (!uci_pkg) {
               syslog(LOG_ERR, "Failed to load configuration\n");
               queues = -1;
               goto done;
       }

       uci_foreach_element(&uci_pkg->sections, uci_elmnt) {
               struct uci_section *uci_sec = uci_to_section(uci_elmnt);
               if (uci_sec && !strcmp(uci_sec->type, "queue")) {
                       struct uci_element *e = NULL;
                       uci_foreach_element(&uci_sec->options, e) {
                               struct uci_option *uci_opn = uci_to_option(e);
                               if (uci_opn && !strcmp(uci_opn->v.string, ifname))
                                       queues++;
                       }
               }
       }

       uci_unload(uci_ctx, uci_pkg);
done:
       uci_free_context(uci_ctx);
       return queues;
}

/**
 *  get_interface_index function for getting interface index i.e., eth0 having index 0
 *  @param ifname input parameter pointer to char for which index needs to be fetched
 *  retrun integer value 0 on success and -1 on failure
 */
static int get_interface_index(const char *ifname)
{
	int i;

	for (i = 0; i < strlen(ifname); i++) {
		if ((ifname[i] >= MIN_INDEX) && (ifname[i] <= MAX_INDEX)) {
			return atoi(ifname + i);
		}
	}

	return -1;
}

/**
 *  get_no_ports function for getting number of ports on device by calling uci port config
 *  @param none
 *  retrun integer value 0 on success and -1 on failure
 */
static int get_no_ports()
{
	int ports = 0;

	struct uci_package *uci_pkg = NULL;
	struct uci_element *uci_elmnt = NULL;
	struct uci_context *uci_ctx = uci_alloc_context();

	uci_load(uci_ctx, "ports", &uci_pkg);
	if (!uci_pkg) {
		syslog(LOG_ERR, "Failed to load configuration\n");
		ports = -1;
		goto done;
	}

	uci_foreach_element(&uci_pkg->sections, uci_elmnt) {
                struct uci_section *uci_sec = uci_to_section(uci_elmnt);
		if (uci_sec)
			ports++;
        }

done:
	uci_unload(uci_ctx, uci_pkg);
	uci_free_context(uci_ctx);
	return ports;
}

/**
 *  init_qstat function for initializing global q_stat structure for sustainable stats
 *  @param none
 *  retrun integer value 0 on success and -1 on failure
 */
static int init_qstat()
{
	int ret = 0;
	int index = 0;

	syslog(LOG_ERR, "Initializing global stat structure.\n");

	int ports = get_no_ports();
	q_stat = (struct qos_stats **)calloc(ports, sizeof(struct qos_stats *));
	if (q_stat == NULL) {
		syslog(LOG_ERR, "Initialization failed during memory allocation.\n");
		ret = -1;
		return ret;
	}

	struct uci_package *uci_pkg = NULL;
	struct uci_element *uci_elmnt = NULL;
	struct uci_context *uci_ctx = uci_alloc_context();

	uci_load(uci_ctx, "ports", &uci_pkg);
	if (!uci_pkg) {
		syslog(LOG_ERR, "Failed to load configuration\n");
		ret = -1;
		goto done;
	}

	uci_foreach_element(&uci_pkg->sections, uci_elmnt) {
                struct uci_section *uci_sec = uci_to_section(uci_elmnt);
		if (uci_sec) {
			struct uci_option *uci_opn = uci_lookup_option(uci_ctx, uci_sec, "ifname");
			index = get_interface_index(uci_opn->v.string);
			int queues = get_no_queues(uci_opn->v.string);
			q_stat[index] = (struct qos_stats *)calloc(queues, sizeof(struct qos_stats));
			if (q_stat[index] == NULL) {
				syslog(LOG_ERR, "Initialization failed during memory allocation.\n");
				ret = -1;
				uci_unload(uci_ctx, uci_pkg);
				goto done;
			}
		}
        }

	uci_unload(uci_ctx, uci_pkg);
done:
	uci_free_context(uci_ctx);
	return ret;
}

/**
 *  prapare_stats_blob function for getting stats by calling libqos function prepare_stats_blob
 *  @param b output parameter pointer to blob_buf
 *  @param stats output parameter pointer to qos_stats actually queue stats container
 *  @param dd output parameter pointer to void used for blob buffer array elements
 *  @param ifname input parameter pointer to char for which to get stats
 *  @param qid input parameter integer queue identifier for which to get stats
 *  retrun integer value 0 on success and -1 on failure
 */
static int prepare_stats_blob(struct blob_buf *b, struct qos_stats *stats, void *dd,
				char *ifname, int qid)
{
	int index;
	int ret = 0;

	// Initialize global q_stat global struct
	if (init_flag) {
		ret = init_qstat();
		if (ret) {
			syslog(LOG_ERR, "Failed to initialize gobal q_stat.\n");
		}
		syslog(LOG_ERR, "Initialized gobal q_stat successfully.\n");
		init_flag = 0;
	}

	ret = qos_get_stats(ifname, qid, stats);
	if (ret != 0) {
		syslog(LOG_ERR, "blob_get_status: ret %d\n", ret);
		return ret;
	}

	index = get_interface_index(ifname);

	q_stat[index][qid].tx_packets += stats->tx_packets;
	q_stat[index][qid].tx_bytes += stats->tx_bytes;
	q_stat[index][qid].tx_dropped_packets += stats->tx_dropped_packets;
	q_stat[index][qid].tx_dropped_bytes += stats->tx_dropped_bytes;

	dd = blobmsg_open_table(b, "");

	blobmsg_add_string(b, "iface", ifname);
	blobmsg_add_u32(b, "qid", qid);
	blobmsg_add_u32(b, "tx_packets", q_stat[index][qid].tx_packets);
	blobmsg_add_u32(b, "tx_bytes", q_stat[index][qid].tx_bytes);
	blobmsg_add_u32(b, "tx_dropped_packets", q_stat[index][qid].tx_dropped_packets);
	blobmsg_add_u32(b, "tx_dropped_bytes", q_stat[index][qid].tx_dropped_bytes);

	blobmsg_close_table(b, dd);

	return ret;
}

/**
 *  get_stats_by_ifname function for getting specific interface stats
 *  @param b output parameter pointer to blob_buf
 *  @param stats output parameter pointer to qos_stats actually queue stats container
 *  @param dd output parameter pointer to void used for blob buffer array elements
 *  @param ifname input parameter pointer to char for which to get stats
 *  @param qid input parameter integer queue identifier for which to get stats
 *  retrun integer value 0 on success and -1 on failure
 */
static int get_stats_by_ifname(struct blob_buf *b, struct qos_stats *stats, void *dd,
				char *ifname, int qid)
{
	int queues = 0;
	int i, ret = 0;

	if (qid >= 0) {
		ret = prepare_stats_blob(b, stats, dd, ifname, qid);
	} else {
		queues = get_no_queues(ifname);
		for (i = 0; i < queues; i++) {
			ret = prepare_stats_blob(b, stats, dd, ifname, i);
			if (ret != 0)
				return ret;
		}
	}

	return ret;
}

/**
 *  get_stats_for_all_intf function for getting all interface stats
 *  @param b output parameter pointer to blob_buf
 *  @param stats output parameter pointer to qos_stats actually queue stats container
 *  @param dd output parameter pointer to void used for blob buffer array elements
 *  retrun integer value 0 on success and -1 on failure
 */
static int get_stats_for_all_intf(struct blob_buf *b, struct qos_stats *stats, void *dd)
{
	int ret = 0;
	char ifname[IFNAMSIZ] = {0};

	struct uci_package *uci_pkg = NULL;
        struct uci_element *uci_elmnt = NULL;
        struct uci_context *uci_ctx = uci_alloc_context();

        uci_load(uci_ctx, "ports", &uci_pkg);
        if (!uci_pkg) {
                syslog(LOG_ERR, "Failed to load configuration\n");
                ret = -1;
		return ret;
        }

        uci_foreach_element(&uci_pkg->sections, uci_elmnt) {
                struct uci_section *uci_sec = uci_to_section(uci_elmnt);
		if (uci_sec) {
			struct uci_option *uci_opn = uci_lookup_option(uci_ctx, uci_sec, "ifname");
			strncpy(ifname, uci_opn->v.string, sizeof(ifname) - 1);
			ret = get_stats_by_ifname(b, stats, dd, ifname, QOS_QUEUE_ANY);
			if (ret != 0) {
				syslog(LOG_ERR, "get_stats_by_ifname : ret %d\n", ret);
				return ret;
			}
		}
        }

	return ret;
}

/**
 *  validate_keys function to validate requested json keys
 *  @param rea_json parameter pointer to char string containing json request
 *  retrun integer value 0 on success and -1 on failure
 */
static int validate_keys(char *req_json)
{
	int i;
	int ret = 0;

	int len = strlen(req_json);

	for (i = 0; i < len; i++) {
		char key[IFNAMSIZ] = {0};
		if (req_json[i] == QUOTE) {
			int j = 0;
			i++;
			while (req_json[i] != QUOTE) {
				key[j] = req_json[i];
				j++;
				i++;
			}
			i++;
			while ((req_json[i] != SEPERATOR) && (i < len))
				i++;

			if (!(!strncmp(key, PARAM1, strlen(PARAM1)) ||
					!strncmp(key, PARAM2, strlen(PARAM2)))) {
				syslog(LOG_ERR, "ERROR :: unknown parameter : %s\n", key);
				return -1;
			}
		}
	}

	return ret;
}

/**
 *  validate_request function to validate requested blob message
 *  @param msg parameter pointer to blob_attr containing blob request
 *  retrun integer value 0 on success and -1 on failure
 */
static int validate_request(struct blob_attr *msg)
{
	int ret = 0;
	char *json_blob = NULL;

	if (msg) {
		json_blob = blobmsg_format_json(msg, true);
		ret = validate_keys(json_blob);
	}

	return ret;
}

/**
 *  qosmngr_get_stats function callback on ubus method queue_stats
 *  @param ctx input parameter pointer to ubus context
 *  @param obj input parameter pointer to ubus object in out case qos
 *  @param req input parameter pointer to ubus requested data
 *  @param method input parameter pointer to char method i.e., queue_stats
 *  @param msg input parameter pointer containing qid and ifname
 *  retrun integer value 0 on success and -1 on failure
 */
int qosmngr_get_stats(struct ubus_context *ctx, struct ubus_object *obj,
	       struct ubus_request_data *req, const char *method,
	       struct blob_attr *msg)
{
	int ret = 0;
	int qid = QOS_QUEUE_ANY;
	char ifname[IFNAMSIZ] = {0};

	struct blob_attr *tb[NUM_QOS_POLICY];
	struct blob_buf b = {0};
	struct qos_stats stats = {0};

	/* Validate requested parameters, i.e., ifname and qid */
	ret = validate_request(msg);
	if (ret) {
		syslog(LOG_ERR, "validate_request failed : ret %d\n", ret);
		return UBUS_STATUS_INVALID_ARGUMENT;
	}

	/* These are for the blobbuf array elements */
	void *d = NULL, *dd = NULL;

	blobmsg_parse(get_status_policy, QOS_POLICY_MAX, tb, blob_data(msg),
							blob_len(msg));

	if (tb[QOS_POLICY_IFNAME])
		strncpy(ifname, blobmsg_data(tb[QOS_POLICY_IFNAME]), sizeof(ifname)-1);

	/* Parse optional arguments */
	if (tb[QOS_POLICY_QID])
		qid = blobmsg_get_u32(tb[QOS_POLICY_QID]);

	/* Can't have a queue id specified without an interface */
	if (tb[QOS_POLICY_QID] && !tb[QOS_POLICY_IFNAME])
		return UBUS_STATUS_INVALID_ARGUMENT;

	blob_buf_init(&b, 0);

	d = blobmsg_open_array(&b, "queues");

	if (tb[QOS_POLICY_IFNAME]) {
		ret = get_stats_by_ifname(&b, &stats, &dd, ifname, qid);
		if (ret != 0) {
			syslog(LOG_ERR, "get_stats_by_ifname : ret %d\n", ret);
			goto fail_get_status;
		}
	} else {
		ret = get_stats_for_all_intf(&b, &stats, &dd);
		if (ret != 0) {
			syslog(LOG_ERR, "get_stats_for_all_intf : ret %d\n", ret);
			goto fail_get_status;
		}
	}

	blobmsg_close_array(&b, d);

	ubus_send_reply(ctx, req, b.head);

 fail_get_status:
	blob_buf_free(&b);
	return ret;
}