esp-firewall/ESPFirewall/lib/Firewall/src/Firewall.cpp

#include "Firewall.hpp"

namespace fw
{
    Firewall::Firewall()
    {
        this->amount_of_rules = retrieve_settings_value("amount_of_rules");
        for (uint8_t i = 1; i <= this->amount_of_rules; i++)
        {
            firewall_rule_t *rule_ptr = retrieve_firewall_rule(i);
            this->add_rule_to_firewall(rule_ptr, false);
        }
    }

    Firewall::~Firewall()
    {
    }

    firewall_rule_t *Firewall::get_rule_head()
    {
        return this->rule_head;
    }

    void Firewall::add_rule_to_firewall(firewall_rule_t *rule_ptr, const bool save_in_eeprom)
    {
        store_settings_value("amount_of_rules", this->amount_of_rules);
        if (save_in_eeprom)
            Storage::store_firewall_rule(rule_ptr);
        if (this->rule_head == NULL)
        {
            this->rule_head = rule_ptr;
            rule_ptr->next = NULL;
            return;
        }
        firewall_rule_t *current_rule;
        current_rule = this->rule_head;
        while (current_rule->next != NULL)
            current_rule = current_rule->next;
        current_rule->next = rule_ptr;
        rule_ptr->next = NULL;
    }

    firewall_rule_t *Firewall::add_rule_to_firewall(String source, String destination, String port_from, String port_to, String protocol, String target)
    {
        firewall_rule_t *rule_ptr = (firewall_rule_t *)malloc(sizeof(firewall_rule_t));
        rule_ptr->key = ++this->amount_of_rules;

        strncpy(rule_ptr->source, source.c_str(), sizeof(rule_ptr->source));
        strncpy(rule_ptr->destination, destination.c_str(), sizeof(rule_ptr->destination));
        rule_ptr->port_from = port_from.toInt();
        rule_ptr->port_to = port_to.toInt();
        rule_ptr->protocol = string_to_protocol(protocol);
        rule_ptr->target = string_to_target(target);

        add_rule_to_firewall(rule_ptr);
        return rule_ptr;
    }

    firewall_rule_t *Firewall::get_rule_from_firewall(const uint8_t key)
    {
        firewall_rule_t *rule_ptr = this->rule_head;
        if (this->rule_head == NULL)
            return NULL;
        while (rule_ptr->key != key)
        {
            if (rule_ptr->next == NULL)
                return NULL;
            else
                rule_ptr = rule_ptr->next;
        }
        return rule_ptr;
    }

    ok_t Firewall::delete_rule_from_firewall(const uint8_t key)
    {
        if (this->rule_head == NULL)
            return NO_ACTION;
        firewall_rule_t *current_rule = this->rule_head;
        firewall_rule_t *previous_rule = NULL;
        firewall_rule_t *temp = NULL;
        while (current_rule->key != key)
        {
            if (current_rule->next == NULL)
                return NO_ACTION;
            else
            {
                previous_rule = current_rule;
                current_rule = current_rule->next;
            }
        }
        if (current_rule == this->rule_head)
        {
            this->rule_head = rule_head->next;
            temp = this->rule_head;
        }
        else
        {
            previous_rule->next = current_rule->next;
            temp = previous_rule->next;
        }
        while (temp != NULL)
        {
            temp->key--;
            temp = temp->next;
        }
        free(current_rule);
        this->amount_of_rules--;
        Storage::store_settings_value("amount_of_rules", this->amount_of_rules);
        if (this->amount_of_rules != 0)
            Storage::store_all_firewall_rules(rule_head);
        return SUCCESS;
    }

    bool Firewall::is_included_in_firewall(const char *ip, const uint16_t port)
    {
        firewall_rule_t *rule_ptr = this->rule_head;
        while (rule_ptr != NULL)
        {
            if (strncmp(ip, rule_ptr->source, IPV4ADDRESS_LENGTH) == 0)
            {
                if (rule_ptr->port_from <= port && port <= rule_ptr->port_to)
                    return true;
            }
            rule_ptr = rule_ptr->next;
        }
        return false;
    }

    bool Firewall::is_client_allowed(WiFiClient client)
    {
        const char *ip = client.remoteIP().toString().c_str();
        const uint16_t port = client.remotePort();

        Serial.print(client.remoteIP());
        Serial.print(":");
        Serial.println(client.remotePort());
        return !is_included_in_firewall(ip, port);
    }
}