ntopng/src/FlowHash.cpp

103 lines
3.2 KiB
C++

/*
*
* (C) 2013-22 - ntop.org
*
*
* 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 3 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, write to the Free Software Foundation,
* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
*/
#include "ntop_includes.h"
/* ************************************ */
FlowHash::FlowHash(NetworkInterface *_iface, u_int _num_hashes, u_int _max_hash_size)
: GenericHash(_iface, _num_hashes, _max_hash_size, "FlowHash") {
;
};
/* ************************************ */
static u_int16_t max_num_loops = 0;
Flow* FlowHash::find(IpAddress *src_ip, IpAddress *dst_ip,
u_int16_t src_port, u_int16_t dst_port,
VLANid vlanId, u_int16_t observation_point_id,
u_int32_t private_flow_id, u_int8_t protocol,
const ICMPinfo * const icmp_info,
bool *src2dst_direction,
bool is_inline_call) {
u_int32_t hash = ((src_ip->key() + dst_ip->key()
+ (icmp_info ? icmp_info->key() : 0)
+ private_flow_id
+ src_port + dst_port + vlanId + protocol) % num_hashes);
Flow *head = (Flow*)table[hash];
u_int16_t num_loops = 0;
// ntop->getTrace()->traceEvent(TRACE_NORMAL, "%u:%u / %u:%u [icmp: %u][key: %u][icmp info key: %u][head: 0x%x]", src_ip->key(), src_port, dst_ip->key(), dst_port, icmp_info ? 1 : 0, hash, icmp_info ? icmp_info->key() : 0, head);
if(!head)
return(NULL);
if(!is_inline_call)
locks[hash]->rdlock(__FILE__, __LINE__);
while(head) {
if(!head->idle()
&& !head->is_swap_done() /* Do NOT return flows for which swap has been done. Leave them so they will be marked as idle and disappear */
&& head->equal(src_ip, dst_ip, src_port, dst_port, vlanId, observation_point_id, private_flow_id, protocol, icmp_info, src2dst_direction)) {
if(num_loops > max_num_loops) {
ntop->getTrace()->traceEvent(TRACE_INFO, "DEBUG: [Num loops: %u][hashId: %u]", num_loops, hash);
max_num_loops = num_loops;
}
break;
} else
head = (Flow*)head->next(), num_loops++;
}
if(num_loops > max_num_loops) {
ntop->getTrace()->traceEvent(TRACE_INFO, "DEBUG: [Num loops: %u][hashId: %u]", num_loops, hash);
max_num_loops = num_loops;
}
if(!is_inline_call)
locks[hash]->unlock(__FILE__, __LINE__);
return(head);
}
/* ************************************ */
Flow* FlowHash::findByKeyAndHashId(u_int32_t key, u_int32_t hash_id) {
u_int32_t hash = key % num_hashes;
Flow *head = (Flow*)table[hash];
if(head == NULL) return(NULL);
locks[hash]->rdlock(__FILE__, __LINE__);
while(head) {
if((!head->idle()) && (head->get_hash_entry_id() == hash_id))
break;
else
head = (Flow*)head->next();
}
locks[hash]->unlock(__FILE__, __LINE__);
return((Flow*)head);
}