mirror of
https://github.com/vel21ripn/nDPI.git
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1078 lines
34 KiB
C
1078 lines
34 KiB
C
/*
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* ndpi_util.c
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*
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* Copyright (C) 2011-18 - ntop.org
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*
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* This file is part of nDPI, an open source deep packet inspection
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* library based on the OpenDPI and PACE technology by ipoque GmbH
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*
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* nDPI is free software: you can redistribute it and/or modify
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* it under the terms of the GNU Lesser General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* nDPI is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public License
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* along with nDPI. If not, see <http://www.gnu.org/licenses/>.
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*
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*/
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#ifdef HAVE_CONFIG_H
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#include "ndpi_config.h"
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#endif
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#include <stdlib.h>
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#ifdef WIN32
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#include <winsock2.h> /* winsock.h is included automatically */
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#include <process.h>
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#include <io.h>
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#else
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#include <unistd.h>
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#include <netinet/in.h>
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#endif
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#ifndef ETH_P_IP
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#define ETH_P_IP 0x0800 /* IPv4 */
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#endif
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#ifndef ETH_P_IPv6
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#define ETH_P_IPV6 0x86dd /* IPv6 */
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#endif
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#define SLARP 0x8035 /* Cisco Slarp */
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#define CISCO_D_PROTO 0x2000 /* Cisco Discovery Protocol */
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#define VLAN 0x8100
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#define MPLS_UNI 0x8847
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#define MPLS_MULTI 0x8848
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#define PPPoE 0x8864
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#define SNAP 0xaa
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#define BSTP 0x42 /* Bridge Spanning Tree Protocol */
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/* mask for FCF */
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#define WIFI_DATA 0x2 /* 0000 0010 */
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#define FCF_TYPE(fc) (((fc) >> 2) & 0x3) /* 0000 0011 = 0x3 */
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#define FCF_SUBTYPE(fc) (((fc) >> 4) & 0xF) /* 0000 1111 = 0xF */
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#define FCF_TO_DS(fc) ((fc) & 0x0100)
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#define FCF_FROM_DS(fc) ((fc) & 0x0200)
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/* mask for Bad FCF presence */
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#define BAD_FCS 0x50 /* 0101 0000 */
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#define GTP_U_V1_PORT 2152
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#define TZSP_PORT 37008
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#ifndef DLT_LINUX_SLL
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#define DLT_LINUX_SLL 113
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#endif
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#include "ndpi_main.h"
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#include "ndpi_util.h"
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/* ***************************************************** */
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void ndpi_free_flow_info_half(struct ndpi_flow_info *flow) {
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if(flow->ndpi_flow) { ndpi_flow_free(flow->ndpi_flow); flow->ndpi_flow = NULL; }
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if(flow->src_id) { ndpi_free(flow->src_id); flow->src_id = NULL; }
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if(flow->dst_id) { ndpi_free(flow->dst_id); flow->dst_id = NULL; }
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}
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/* ***************************************************** */
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extern u_int32_t current_ndpi_memory, max_ndpi_memory;
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/**
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* @brief malloc wrapper function
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*/
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static void *malloc_wrapper(size_t size) {
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current_ndpi_memory += size;
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if(current_ndpi_memory > max_ndpi_memory)
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max_ndpi_memory = current_ndpi_memory;
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return malloc(size);
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}
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/* ***************************************************** */
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/**
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* @brief free wrapper function
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*/
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static void free_wrapper(void *freeable) {
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free(freeable);
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}
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/* ***************************************************** */
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static uint16_t ndpi_get_proto_id(struct ndpi_detection_module_struct *ndpi_mod, const char *name) {
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uint16_t proto_id;
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char *e;
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unsigned long p = strtol(name,&e,0);
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ndpi_proto_defaults_t *proto_defaults = ndpi_get_proto_defaults(ndpi_mod);
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if(e && !*e) {
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if(p < NDPI_MAX_SUPPORTED_PROTOCOLS+NDPI_MAX_NUM_CUSTOM_PROTOCOLS &&
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proto_defaults[p].protoName) return (uint16_t)p;
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return NDPI_PROTOCOL_UNKNOWN;
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}
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for(proto_id=NDPI_PROTOCOL_UNKNOWN; proto_id < NDPI_MAX_SUPPORTED_PROTOCOLS+NDPI_MAX_NUM_CUSTOM_PROTOCOLS; proto_id++) {
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if(proto_defaults[proto_id].protoName &&
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!strcasecmp(proto_defaults[proto_id].protoName,name))
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return proto_id;
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}
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return NDPI_PROTOCOL_UNKNOWN;
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}
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/* ***************************************************** */
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static NDPI_PROTOCOL_BITMASK debug_bitmask;
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static char _proto_delim[] = " \t,:;";
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static int parse_debug_proto(struct ndpi_detection_module_struct *ndpi_mod, char *str) {
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char *n;
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uint16_t proto;
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char op=1;
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for(n = strtok(str,_proto_delim); n && *n; n = strtok(NULL,_proto_delim)) {
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if(*n == '-') {
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op = 0;
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n++;
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} else if(*n == '+') {
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op = 1;
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n++;
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}
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if(!strcmp(n,"all")) {
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if(op)
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NDPI_BITMASK_SET_ALL(debug_bitmask);
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else
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NDPI_BITMASK_RESET(debug_bitmask);
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continue;
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}
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proto = ndpi_get_proto_id(ndpi_mod, n);
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if(proto == NDPI_PROTOCOL_UNKNOWN && strcmp(n,"unknown") && strcmp(n,"0")) {
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fprintf(stderr,"Invalid protocol %s\n",n);
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return 1;
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}
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if(op)
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NDPI_BITMASK_ADD(debug_bitmask,proto);
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else
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NDPI_BITMASK_DEL(debug_bitmask,proto);
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}
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return 0;
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}
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/* ***************************************************** */
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extern char *_debug_protocols;
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static int _debug_protocols_ok = 0;
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struct ndpi_workflow* ndpi_workflow_init(const struct ndpi_workflow_prefs * prefs,
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pcap_t * pcap_handle) {
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set_ndpi_malloc(malloc_wrapper), set_ndpi_free(free_wrapper);
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set_ndpi_flow_malloc(NULL), set_ndpi_flow_free(NULL);
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/* TODO: just needed here to init ndpi malloc wrapper */
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struct ndpi_detection_module_struct * module = ndpi_init_detection_module();
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struct ndpi_workflow * workflow = ndpi_calloc(1, sizeof(struct ndpi_workflow));
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workflow->pcap_handle = pcap_handle;
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workflow->prefs = *prefs;
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workflow->ndpi_struct = module;
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if(workflow->ndpi_struct == NULL) {
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NDPI_LOG(0, NULL, NDPI_LOG_ERROR, "global structure initialization failed\n");
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exit(-1);
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}
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ndpi_set_log_level(module, nDPI_LogLevel);
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if(_debug_protocols != NULL && ! _debug_protocols_ok) {
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if(parse_debug_proto(module,_debug_protocols))
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exit(-1);
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_debug_protocols_ok = 1;
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}
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#ifdef NDPI_ENABLE_DEBUG_MESSAGES
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NDPI_BITMASK_RESET(module->debug_bitmask);
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if(_debug_protocols_ok)
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module->debug_bitmask = debug_bitmask;
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#endif
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workflow->ndpi_flows_root = ndpi_calloc(workflow->prefs.num_roots, sizeof(void *));
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return workflow;
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}
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/* ***************************************************** */
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void ndpi_flow_info_freer(void *node) {
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struct ndpi_flow_info *flow = (struct ndpi_flow_info*)node;
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ndpi_free_flow_info_half(flow);
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ndpi_free(flow);
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}
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/* ***************************************************** */
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void ndpi_workflow_free(struct ndpi_workflow * workflow) {
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int i;
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for(i=0; i<workflow->prefs.num_roots; i++)
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ndpi_tdestroy(workflow->ndpi_flows_root[i], ndpi_flow_info_freer);
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ndpi_exit_detection_module(workflow->ndpi_struct);
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free(workflow->ndpi_flows_root);
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free(workflow);
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}
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/* ***************************************************** */
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int ndpi_workflow_node_cmp(const void *a, const void *b) {
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struct ndpi_flow_info *fa = (struct ndpi_flow_info*)a;
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struct ndpi_flow_info *fb = (struct ndpi_flow_info*)b;
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if(fa->hashval < fb->hashval) return(-1); else if(fa->hashval > fb->hashval) return(1);
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/* Flows have the same hash */
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if(fa->vlan_id < fb->vlan_id ) return(-1); else { if(fa->vlan_id > fb->vlan_id ) return(1); }
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if(fa->protocol < fb->protocol ) return(-1); else { if(fa->protocol > fb->protocol ) return(1); }
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if(
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(
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(fa->src_ip == fb->src_ip )
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&& (fa->src_port == fb->src_port)
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&& (fa->dst_ip == fb->dst_ip )
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&& (fa->dst_port == fb->dst_port)
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)
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||
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(
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(fa->src_ip == fb->dst_ip )
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&& (fa->src_port == fb->dst_port)
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&& (fa->dst_ip == fb->src_ip )
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&& (fa->dst_port == fb->src_port)
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)
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)
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return(0);
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if(fa->src_ip < fb->src_ip ) return(-1); else { if(fa->src_ip > fb->src_ip ) return(1); }
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if(fa->src_port < fb->src_port) return(-1); else { if(fa->src_port > fb->src_port) return(1); }
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if(fa->dst_ip < fb->dst_ip ) return(-1); else { if(fa->dst_ip > fb->dst_ip ) return(1); }
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if(fa->dst_port < fb->dst_port) return(-1); else { if(fa->dst_port > fb->dst_port) return(1); }
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return(0); /* notreached */
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}
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/* ***************************************************** */
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static void patchIPv6Address(char *str) {
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int i = 0, j = 0;
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while(str[i] != '\0') {
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if((str[i] == ':')
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&& (str[i+1] == '0')
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&& (str[i+2] == ':')) {
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str[j++] = ':';
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str[j++] = ':';
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i += 3;
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} else
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str[j++] = str[i++];
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}
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if(str[j] != '\0') str[j] = '\0';
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}
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/* ***************************************************** */
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static struct ndpi_flow_info *get_ndpi_flow_info(struct ndpi_workflow * workflow,
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const u_int8_t version,
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u_int16_t vlan_id,
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const struct ndpi_iphdr *iph,
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const struct ndpi_ipv6hdr *iph6,
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u_int16_t ip_offset,
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u_int16_t ipsize,
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u_int16_t l4_packet_len,
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struct ndpi_tcphdr **tcph,
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struct ndpi_udphdr **udph,
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u_int16_t *sport, u_int16_t *dport,
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struct ndpi_id_struct **src,
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struct ndpi_id_struct **dst,
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u_int8_t *proto,
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u_int8_t **payload,
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u_int16_t *payload_len,
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u_int8_t *src_to_dst_direction) {
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u_int32_t idx, l4_offset, hashval;
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struct ndpi_flow_info flow;
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void *ret;
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u_int8_t *l3, *l4;
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/*
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Note: to keep things simple (ndpiReader is just a demo app)
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we handle IPv6 a-la-IPv4.
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*/
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if(version == IPVERSION) {
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if(ipsize < 20)
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return NULL;
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if((iph->ihl * 4) > ipsize || ipsize < ntohs(iph->tot_len)
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/* || (iph->frag_off & htons(0x1FFF)) != 0 */)
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return NULL;
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l4_offset = iph->ihl * 4;
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l3 = (u_int8_t*)iph;
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} else {
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l4_offset = sizeof(struct ndpi_ipv6hdr);
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l3 = (u_int8_t*)iph6;
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}
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if(l4_packet_len < 64)
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workflow->stats.packet_len[0]++;
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else if(l4_packet_len >= 64 && l4_packet_len < 128)
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workflow->stats.packet_len[1]++;
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else if(l4_packet_len >= 128 && l4_packet_len < 256)
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workflow->stats.packet_len[2]++;
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else if(l4_packet_len >= 256 && l4_packet_len < 1024)
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workflow->stats.packet_len[3]++;
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else if(l4_packet_len >= 1024 && l4_packet_len < 1500)
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workflow->stats.packet_len[4]++;
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else if(l4_packet_len >= 1500)
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workflow->stats.packet_len[5]++;
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if(l4_packet_len > workflow->stats.max_packet_len)
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workflow->stats.max_packet_len = l4_packet_len;
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*proto = iph->protocol;
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l4 = ((u_int8_t *) l3 + l4_offset);
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if(iph->protocol == IPPROTO_TCP && l4_packet_len >= 20) {
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u_int tcp_len;
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// tcp
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workflow->stats.tcp_count++;
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*tcph = (struct ndpi_tcphdr *)l4;
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*sport = ntohs((*tcph)->source), *dport = ntohs((*tcph)->dest);
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tcp_len = ndpi_min(4*(*tcph)->doff, l4_packet_len);
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*payload = &l4[tcp_len];
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*payload_len = ndpi_max(0, l4_packet_len-4*(*tcph)->doff);
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} else if(iph->protocol == IPPROTO_UDP && l4_packet_len >= 8) {
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// udp
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workflow->stats.udp_count++;
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*udph = (struct ndpi_udphdr *)l4;
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*sport = ntohs((*udph)->source), *dport = ntohs((*udph)->dest);
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*payload = &l4[sizeof(struct ndpi_udphdr)];
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*payload_len = ndpi_max(0, l4_packet_len-sizeof(struct ndpi_udphdr));
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} else {
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// non tcp/udp protocols
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*sport = *dport = 0;
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}
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flow.protocol = iph->protocol, flow.vlan_id = vlan_id;
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flow.src_ip = iph->saddr, flow.dst_ip = iph->daddr;
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flow.src_port = htons(*sport), flow.dst_port = htons(*dport);
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flow.hashval = hashval = flow.protocol + flow.vlan_id + flow.src_ip + flow.dst_ip + flow.src_port + flow.dst_port;
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idx = hashval % workflow->prefs.num_roots;
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ret = ndpi_tfind(&flow, &workflow->ndpi_flows_root[idx], ndpi_workflow_node_cmp);
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/* to avoid two nodes in one binary tree for a flow */
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int is_changed = 0;
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if(ret == NULL) {
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u_int32_t orig_src_ip = flow.src_ip;
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u_int16_t orig_src_port = flow.src_port;
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u_int32_t orig_dst_ip = flow.dst_ip;
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u_int16_t orig_dst_port = flow.dst_port;
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flow.src_ip = orig_dst_ip;
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flow.src_port = orig_dst_port;
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flow.dst_ip = orig_src_ip;
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flow.dst_port = orig_src_port;
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is_changed = 1;
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ret = ndpi_tfind(&flow, &workflow->ndpi_flows_root[idx], ndpi_workflow_node_cmp);
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}
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if(ret == NULL) {
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if(workflow->stats.ndpi_flow_count == workflow->prefs.max_ndpi_flows) {
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NDPI_LOG(0, workflow->ndpi_struct, NDPI_LOG_ERROR,
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"maximum flow count (%u) has been exceeded\n",
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workflow->prefs.max_ndpi_flows);
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exit(-1);
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} else {
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struct ndpi_flow_info *newflow = (struct ndpi_flow_info*)malloc(sizeof(struct ndpi_flow_info));
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if(newflow == NULL) {
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NDPI_LOG(0, workflow->ndpi_struct, NDPI_LOG_ERROR, "[NDPI] %s(1): not enough memory\n", __FUNCTION__);
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return(NULL);
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} else
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workflow->num_allocated_flows++;
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memset(newflow, 0, sizeof(struct ndpi_flow_info));
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newflow->hashval = hashval;
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newflow->protocol = iph->protocol, newflow->vlan_id = vlan_id;
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newflow->src_ip = iph->saddr, newflow->dst_ip = iph->daddr;
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newflow->src_port = htons(*sport), newflow->dst_port = htons(*dport);
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newflow->ip_version = version;
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if(version == IPVERSION) {
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inet_ntop(AF_INET, &newflow->src_ip, newflow->src_name, sizeof(newflow->src_name));
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inet_ntop(AF_INET, &newflow->dst_ip, newflow->dst_name, sizeof(newflow->dst_name));
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} else {
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inet_ntop(AF_INET6, &iph6->ip6_src, newflow->src_name, sizeof(newflow->src_name));
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inet_ntop(AF_INET6, &iph6->ip6_dst, newflow->dst_name, sizeof(newflow->dst_name));
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/* For consistency across platforms replace :0: with :: */
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patchIPv6Address(newflow->src_name), patchIPv6Address(newflow->dst_name);
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}
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if((newflow->ndpi_flow = ndpi_flow_malloc(SIZEOF_FLOW_STRUCT)) == NULL) {
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NDPI_LOG(0, workflow->ndpi_struct, NDPI_LOG_ERROR, "[NDPI] %s(2): not enough memory\n", __FUNCTION__);
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free(newflow);
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return(NULL);
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} else
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memset(newflow->ndpi_flow, 0, SIZEOF_FLOW_STRUCT);
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if((newflow->src_id = ndpi_malloc(SIZEOF_ID_STRUCT)) == NULL) {
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NDPI_LOG(0, workflow->ndpi_struct, NDPI_LOG_ERROR, "[NDPI] %s(3): not enough memory\n", __FUNCTION__);
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free(newflow);
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return(NULL);
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} else
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memset(newflow->src_id, 0, SIZEOF_ID_STRUCT);
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if((newflow->dst_id = ndpi_malloc(SIZEOF_ID_STRUCT)) == NULL) {
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NDPI_LOG(0, workflow->ndpi_struct, NDPI_LOG_ERROR, "[NDPI] %s(4): not enough memory\n", __FUNCTION__);
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free(newflow);
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return(NULL);
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} else
|
|
memset(newflow->dst_id, 0, SIZEOF_ID_STRUCT);
|
|
|
|
ndpi_tsearch(newflow, &workflow->ndpi_flows_root[idx], ndpi_workflow_node_cmp); /* Add */
|
|
workflow->stats.ndpi_flow_count++;
|
|
|
|
*src = newflow->src_id, *dst = newflow->dst_id;
|
|
|
|
return newflow;
|
|
}
|
|
} else {
|
|
struct ndpi_flow_info *flow = *(struct ndpi_flow_info**)ret;
|
|
|
|
if(is_changed) {
|
|
if(flow->src_ip == iph->saddr
|
|
&& flow->dst_ip == iph->daddr
|
|
&& flow->src_port == htons(*sport)
|
|
&& flow->dst_port == htons(*dport)
|
|
)
|
|
*src = flow->dst_id, *dst = flow->src_id, *src_to_dst_direction = 0, flow->bidirectional = 1;
|
|
else
|
|
*src = flow->src_id, *dst = flow->dst_id, *src_to_dst_direction = 1;
|
|
}
|
|
else {
|
|
if(flow->src_ip == iph->saddr
|
|
&& flow->dst_ip == iph->daddr
|
|
&& flow->src_port == htons(*sport)
|
|
&& flow->dst_port == htons(*dport)
|
|
)
|
|
*src = flow->src_id, *dst = flow->dst_id, *src_to_dst_direction = 1;
|
|
else
|
|
*src = flow->dst_id, *dst = flow->src_id, *src_to_dst_direction = 0, flow->bidirectional = 1;
|
|
}
|
|
return flow;
|
|
}
|
|
}
|
|
|
|
/* ****************************************************** */
|
|
|
|
static struct ndpi_flow_info *get_ndpi_flow_info6(struct ndpi_workflow * workflow,
|
|
u_int16_t vlan_id,
|
|
const struct ndpi_ipv6hdr *iph6,
|
|
u_int16_t ip_offset,
|
|
struct ndpi_tcphdr **tcph,
|
|
struct ndpi_udphdr **udph,
|
|
u_int16_t *sport, u_int16_t *dport,
|
|
struct ndpi_id_struct **src,
|
|
struct ndpi_id_struct **dst,
|
|
u_int8_t *proto,
|
|
u_int8_t **payload,
|
|
u_int16_t *payload_len,
|
|
u_int8_t *src_to_dst_direction) {
|
|
struct ndpi_iphdr iph;
|
|
|
|
memset(&iph, 0, sizeof(iph));
|
|
iph.version = IPVERSION;
|
|
iph.saddr = iph6->ip6_src.u6_addr.u6_addr32[2] + iph6->ip6_src.u6_addr.u6_addr32[3];
|
|
iph.daddr = iph6->ip6_dst.u6_addr.u6_addr32[2] + iph6->ip6_dst.u6_addr.u6_addr32[3];
|
|
iph.protocol = iph6->ip6_hdr.ip6_un1_nxt;
|
|
|
|
if(iph.protocol == IPPROTO_DSTOPTS /* IPv6 destination option */) {
|
|
u_int8_t *options = (u_int8_t*)iph6 + sizeof(const struct ndpi_ipv6hdr);
|
|
|
|
iph.protocol = options[0];
|
|
}
|
|
|
|
return(get_ndpi_flow_info(workflow, 6, vlan_id, &iph, iph6, ip_offset,
|
|
sizeof(struct ndpi_ipv6hdr),
|
|
ntohs(iph6->ip6_hdr.ip6_un1_plen),
|
|
tcph, udph, sport, dport,
|
|
src, dst, proto, payload,
|
|
payload_len, src_to_dst_direction));
|
|
}
|
|
|
|
/* ****************************************************** */
|
|
|
|
void process_ndpi_collected_info(struct ndpi_workflow * workflow, struct ndpi_flow_info *flow) {
|
|
if(!flow->ndpi_flow) return;
|
|
|
|
snprintf(flow->host_server_name, sizeof(flow->host_server_name), "%s",
|
|
flow->ndpi_flow->host_server_name);
|
|
|
|
/* BITTORRENT */
|
|
if(flow->detected_protocol.app_protocol == NDPI_PROTOCOL_BITTORRENT) {
|
|
int i, j, n = 0;
|
|
|
|
for(i=0, j = 0; j < sizeof(flow->bittorent_hash)-1; i++) {
|
|
sprintf(&flow->bittorent_hash[j], "%02x",
|
|
flow->ndpi_flow->protos.bittorrent.hash[i]);
|
|
|
|
j += 2, n += flow->ndpi_flow->protos.bittorrent.hash[i];
|
|
}
|
|
|
|
if(n == 0) flow->bittorent_hash[0] = '\0';
|
|
}
|
|
/* MDNS */
|
|
else if(flow->detected_protocol.app_protocol == NDPI_PROTOCOL_MDNS) {
|
|
snprintf(flow->info, sizeof(flow->info), "%s", flow->ndpi_flow->protos.mdns.answer);
|
|
}
|
|
/* UBNTAC2 */
|
|
else if(flow->detected_protocol.app_protocol == NDPI_PROTOCOL_UBNTAC2) {
|
|
snprintf(flow->info, sizeof(flow->info), "%s", flow->ndpi_flow->protos.ubntac2.version);
|
|
}
|
|
if(flow->detected_protocol.app_protocol != NDPI_PROTOCOL_DNS) {
|
|
/* SSH */
|
|
if(flow->detected_protocol.app_protocol == NDPI_PROTOCOL_SSH) {
|
|
snprintf(flow->ssh_ssl.client_info, sizeof(flow->ssh_ssl.client_info), "%s",
|
|
flow->ndpi_flow->protos.ssh.client_signature);
|
|
snprintf(flow->ssh_ssl.server_info, sizeof(flow->ssh_ssl.server_info), "%s",
|
|
flow->ndpi_flow->protos.ssh.server_signature);
|
|
}
|
|
/* SSL */
|
|
else if((flow->detected_protocol.app_protocol == NDPI_PROTOCOL_SSL)
|
|
|| (flow->detected_protocol.master_protocol == NDPI_PROTOCOL_SSL)) {
|
|
snprintf(flow->ssh_ssl.client_info, sizeof(flow->ssh_ssl.client_info), "%s",
|
|
flow->ndpi_flow->protos.stun_ssl.ssl.client_certificate);
|
|
snprintf(flow->ssh_ssl.server_info, sizeof(flow->ssh_ssl.server_info), "%s",
|
|
flow->ndpi_flow->protos.stun_ssl.ssl.server_certificate);
|
|
}
|
|
}
|
|
|
|
if(flow->detection_completed && !flow->check_extra_packets) {
|
|
if(flow->detected_protocol.app_protocol == NDPI_PROTOCOL_UNKNOWN) {
|
|
if(workflow->__flow_giveup_callback != NULL)
|
|
workflow->__flow_giveup_callback(workflow, flow, workflow->__flow_giveup_udata);
|
|
} else {
|
|
if(workflow->__flow_detected_callback != NULL)
|
|
workflow->__flow_detected_callback(workflow, flow, workflow->__flow_detected_udata);
|
|
}
|
|
|
|
ndpi_free_flow_info_half(flow);
|
|
}
|
|
}
|
|
|
|
/* ****************************************************** */
|
|
|
|
/**
|
|
Function to process the packet:
|
|
determine the flow of a packet and try to decode it
|
|
@return: 0 if success; else != 0
|
|
|
|
@Note: ipsize = header->len - ip_offset ; rawsize = header->len
|
|
*/
|
|
static struct ndpi_proto packet_processing(struct ndpi_workflow * workflow,
|
|
const u_int64_t time,
|
|
u_int16_t vlan_id,
|
|
const struct ndpi_iphdr *iph,
|
|
struct ndpi_ipv6hdr *iph6,
|
|
u_int16_t ip_offset,
|
|
u_int16_t ipsize, u_int16_t rawsize) {
|
|
struct ndpi_id_struct *src, *dst;
|
|
struct ndpi_flow_info *flow = NULL;
|
|
struct ndpi_flow_struct *ndpi_flow = NULL;
|
|
u_int8_t proto;
|
|
struct ndpi_tcphdr *tcph = NULL;
|
|
struct ndpi_udphdr *udph = NULL;
|
|
u_int16_t sport, dport, payload_len;
|
|
u_int8_t *payload;
|
|
u_int8_t src_to_dst_direction = 1;
|
|
struct ndpi_proto nproto = { NDPI_PROTOCOL_UNKNOWN, NDPI_PROTOCOL_UNKNOWN };
|
|
|
|
if(iph)
|
|
flow = get_ndpi_flow_info(workflow, IPVERSION, vlan_id, iph, NULL,
|
|
ip_offset, ipsize,
|
|
ntohs(iph->tot_len) - (iph->ihl * 4),
|
|
&tcph, &udph, &sport, &dport,
|
|
&src, &dst, &proto,
|
|
&payload, &payload_len, &src_to_dst_direction);
|
|
else
|
|
flow = get_ndpi_flow_info6(workflow, vlan_id, iph6, ip_offset,
|
|
&tcph, &udph, &sport, &dport,
|
|
&src, &dst, &proto,
|
|
&payload, &payload_len, &src_to_dst_direction);
|
|
|
|
if(flow != NULL) {
|
|
workflow->stats.ip_packet_count++;
|
|
workflow->stats.total_wire_bytes += rawsize + 24 /* CRC etc */,
|
|
workflow->stats.total_ip_bytes += rawsize;
|
|
ndpi_flow = flow->ndpi_flow;
|
|
|
|
if(src_to_dst_direction)
|
|
flow->src2dst_packets++, flow->src2dst_bytes += rawsize;
|
|
else
|
|
flow->dst2src_packets++, flow->dst2src_bytes += rawsize;
|
|
|
|
flow->last_seen = time;
|
|
} else { // flow is NULL
|
|
workflow->stats.total_discarded_bytes++;
|
|
return(nproto);
|
|
}
|
|
|
|
/* Protocol already detected */
|
|
if(flow->detection_completed) {
|
|
if(flow->check_extra_packets && ndpi_flow != NULL && ndpi_flow->check_extra_packets) {
|
|
if(ndpi_flow->num_extra_packets_checked == 0 && ndpi_flow->max_extra_packets_to_check == 0) {
|
|
/* Protocols can set this, but we set it here in case they didn't */
|
|
ndpi_flow->max_extra_packets_to_check = MAX_EXTRA_PACKETS_TO_CHECK;
|
|
}
|
|
if(ndpi_flow->num_extra_packets_checked < ndpi_flow->max_extra_packets_to_check) {
|
|
ndpi_process_extra_packet(workflow->ndpi_struct, ndpi_flow,
|
|
iph ? (uint8_t *)iph : (uint8_t *)iph6,
|
|
ipsize, time, src, dst);
|
|
if(ndpi_flow->check_extra_packets == 0) {
|
|
flow->check_extra_packets = 0;
|
|
process_ndpi_collected_info(workflow, flow);
|
|
}
|
|
}
|
|
} else if(ndpi_flow != NULL) {
|
|
/* If this wasn't NULL we should do the half free */
|
|
/* TODO: When half_free is deprecated, get rid of this */
|
|
ndpi_free_flow_info_half(flow);
|
|
}
|
|
|
|
return(flow->detected_protocol);
|
|
}
|
|
|
|
flow->detected_protocol =
|
|
ndpi_detection_process_packet(workflow->ndpi_struct, ndpi_flow,
|
|
iph ? (uint8_t *)iph : (uint8_t *)iph6,
|
|
ipsize, time, src, dst);
|
|
|
|
if((flow->detected_protocol.app_protocol != NDPI_PROTOCOL_UNKNOWN)
|
|
|| ((proto == IPPROTO_UDP) && ((flow->src2dst_packets + flow->dst2src_packets) > 8))
|
|
|| ((proto == IPPROTO_TCP) && ((flow->src2dst_packets + flow->dst2src_packets) > 10))) {
|
|
/* New protocol detected or give up */
|
|
flow->detection_completed = 1;
|
|
/* Check if we should keep checking extra packets */
|
|
if(ndpi_flow->check_extra_packets)
|
|
flow->check_extra_packets = 1;
|
|
|
|
if(flow->detected_protocol.app_protocol == NDPI_PROTOCOL_UNKNOWN)
|
|
flow->detected_protocol = ndpi_detection_giveup(workflow->ndpi_struct,
|
|
flow->ndpi_flow);
|
|
process_ndpi_collected_info(workflow, flow);
|
|
}
|
|
|
|
return(flow->detected_protocol);
|
|
}
|
|
|
|
/* ****************************************************** */
|
|
|
|
struct ndpi_proto ndpi_workflow_process_packet (struct ndpi_workflow * workflow,
|
|
const struct pcap_pkthdr *header,
|
|
const u_char *packet) {
|
|
/*
|
|
* Declare pointers to packet headers
|
|
*/
|
|
/* --- Ethernet header --- */
|
|
const struct ndpi_ethhdr *ethernet;
|
|
/* --- LLC header --- */
|
|
const struct ndpi_llc_header_snap *llc;
|
|
|
|
/* --- Cisco HDLC header --- */
|
|
const struct ndpi_chdlc *chdlc;
|
|
|
|
/* --- Radio Tap header --- */
|
|
const struct ndpi_radiotap_header *radiotap;
|
|
/* --- Wifi header --- */
|
|
const struct ndpi_wifi_header *wifi;
|
|
|
|
/* --- MPLS header --- */
|
|
union mpls {
|
|
uint32_t u32;
|
|
struct ndpi_mpls_header mpls;
|
|
} mpls;
|
|
|
|
/** --- IP header --- **/
|
|
struct ndpi_iphdr *iph;
|
|
/** --- IPv6 header --- **/
|
|
struct ndpi_ipv6hdr *iph6;
|
|
|
|
struct ndpi_proto nproto = { NDPI_PROTOCOL_UNKNOWN, NDPI_PROTOCOL_UNKNOWN };
|
|
|
|
/* lengths and offsets */
|
|
u_int16_t eth_offset = 0;
|
|
u_int16_t radio_len;
|
|
u_int16_t fc;
|
|
u_int16_t type = 0;
|
|
int wifi_len = 0;
|
|
int pyld_eth_len = 0;
|
|
int check;
|
|
u_int64_t time;
|
|
u_int16_t ip_offset = 0, ip_len;
|
|
u_int16_t frag_off = 0, vlan_id = 0;
|
|
u_int8_t proto = 0;
|
|
u_int32_t label;
|
|
|
|
/* counters */
|
|
u_int8_t vlan_packet = 0;
|
|
|
|
/* Increment raw packet counter */
|
|
workflow->stats.raw_packet_count++;
|
|
|
|
/* setting time */
|
|
time = ((uint64_t) header->ts.tv_sec) * TICK_RESOLUTION + header->ts.tv_usec / (1000000 / TICK_RESOLUTION);
|
|
|
|
/* safety check */
|
|
if(workflow->last_time > time) {
|
|
/* printf("\nWARNING: timestamp bug in the pcap file (ts delta: %llu, repairing)\n", ndpi_thread_info[thread_id].last_time - time); */
|
|
time = workflow->last_time;
|
|
}
|
|
/* update last time value */
|
|
workflow->last_time = time;
|
|
|
|
/*** check Data Link type ***/
|
|
const int datalink_type = pcap_datalink(workflow->pcap_handle);
|
|
|
|
datalink_check:
|
|
switch(datalink_type) {
|
|
case DLT_NULL:
|
|
if(ntohl(*((u_int32_t*)&packet[eth_offset])) == 2)
|
|
type = ETH_P_IP;
|
|
else
|
|
type = ETH_P_IPV6;
|
|
|
|
ip_offset = 4 + eth_offset;
|
|
break;
|
|
|
|
/* Cisco PPP in HDLC-like framing - 50 */
|
|
case DLT_PPP_SERIAL:
|
|
chdlc = (struct ndpi_chdlc *) &packet[eth_offset];
|
|
ip_offset = sizeof(struct ndpi_chdlc); /* CHDLC_OFF = 4 */
|
|
type = ntohs(chdlc->proto_code);
|
|
break;
|
|
|
|
/* Cisco PPP - 9 or 104 */
|
|
case DLT_C_HDLC:
|
|
case DLT_PPP:
|
|
chdlc = (struct ndpi_chdlc *) &packet[eth_offset];
|
|
ip_offset = sizeof(struct ndpi_chdlc); /* CHDLC_OFF = 4 */
|
|
type = ntohs(chdlc->proto_code);
|
|
break;
|
|
|
|
/* IEEE 802.3 Ethernet - 1 */
|
|
case DLT_EN10MB:
|
|
ethernet = (struct ndpi_ethhdr *) &packet[eth_offset];
|
|
ip_offset = sizeof(struct ndpi_ethhdr) + eth_offset;
|
|
check = ntohs(ethernet->h_proto);
|
|
|
|
if(check <= 1500)
|
|
pyld_eth_len = check;
|
|
else if(check >= 1536)
|
|
type = check;
|
|
|
|
if(pyld_eth_len != 0) {
|
|
llc = (struct ndpi_llc_header_snap *)(&packet[ip_offset]);
|
|
/* check for LLC layer with SNAP extension */
|
|
if(llc->dsap == SNAP || llc->ssap == SNAP) {
|
|
type = llc->snap.proto_ID;
|
|
ip_offset += + 8;
|
|
}
|
|
/* No SNAP extension - Spanning Tree pkt must be discarted */
|
|
else if(llc->dsap == BSTP || llc->ssap == BSTP) {
|
|
goto v4_warning;
|
|
}
|
|
}
|
|
break;
|
|
|
|
/* Linux Cooked Capture - 113 */
|
|
case DLT_LINUX_SLL:
|
|
type = (packet[eth_offset+14] << 8) + packet[eth_offset+15];
|
|
ip_offset = 16 + eth_offset;
|
|
break;
|
|
|
|
/* Radiotap link-layer - 127 */
|
|
case DLT_IEEE802_11_RADIO:
|
|
radiotap = (struct ndpi_radiotap_header *) &packet[eth_offset];
|
|
radio_len = radiotap->len;
|
|
|
|
/* Check Bad FCS presence */
|
|
if((radiotap->flags & BAD_FCS) == BAD_FCS) {
|
|
workflow->stats.total_discarded_bytes += header->len;
|
|
return(nproto);
|
|
}
|
|
|
|
/* Calculate 802.11 header length (variable) */
|
|
wifi = (struct ndpi_wifi_header*)( packet + eth_offset + radio_len);
|
|
fc = wifi->fc;
|
|
|
|
/* check wifi data presence */
|
|
if(FCF_TYPE(fc) == WIFI_DATA) {
|
|
if((FCF_TO_DS(fc) && FCF_FROM_DS(fc) == 0x0) ||
|
|
(FCF_TO_DS(fc) == 0x0 && FCF_FROM_DS(fc)))
|
|
wifi_len = 26; /* + 4 byte fcs */
|
|
} else /* no data frames */
|
|
break;
|
|
|
|
/* Check ether_type from LLC */
|
|
llc = (struct ndpi_llc_header_snap*)(packet + eth_offset + wifi_len + radio_len);
|
|
if(llc->dsap == SNAP)
|
|
type = ntohs(llc->snap.proto_ID);
|
|
|
|
/* Set IP header offset */
|
|
ip_offset = wifi_len + radio_len + sizeof(struct ndpi_llc_header_snap) + eth_offset;
|
|
break;
|
|
|
|
case DLT_RAW:
|
|
ip_offset = eth_offset = 0;
|
|
break;
|
|
|
|
default:
|
|
/* printf("Unknown datalink %d\n", datalink_type); */
|
|
return(nproto);
|
|
}
|
|
|
|
/* check ether type */
|
|
switch(type) {
|
|
case VLAN:
|
|
vlan_id = ((packet[ip_offset] << 8) + packet[ip_offset+1]) & 0xFFF;
|
|
type = (packet[ip_offset+2] << 8) + packet[ip_offset+3];
|
|
ip_offset += 4;
|
|
vlan_packet = 1;
|
|
// double tagging for 802.1Q
|
|
if(type == 0x8100) {
|
|
vlan_id = ((packet[ip_offset] << 8) + packet[ip_offset+1]) & 0xFFF;
|
|
type = (packet[ip_offset+2] << 8) + packet[ip_offset+3];
|
|
ip_offset += 4;
|
|
}
|
|
break;
|
|
case MPLS_UNI:
|
|
case MPLS_MULTI:
|
|
mpls.u32 = *((uint32_t *) &packet[ip_offset]);
|
|
mpls.u32 = ntohl(mpls.u32);
|
|
workflow->stats.mpls_count++;
|
|
type = ETH_P_IP, ip_offset += 4;
|
|
|
|
while(!mpls.mpls.s) {
|
|
mpls.u32 = *((uint32_t *) &packet[ip_offset]);
|
|
mpls.u32 = ntohl(mpls.u32);
|
|
ip_offset += 4;
|
|
}
|
|
break;
|
|
case PPPoE:
|
|
workflow->stats.pppoe_count++;
|
|
type = ETH_P_IP;
|
|
ip_offset += 8;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
workflow->stats.vlan_count += vlan_packet;
|
|
|
|
iph_check:
|
|
/* Check and set IP header size and total packet length */
|
|
iph = (struct ndpi_iphdr *) &packet[ip_offset];
|
|
|
|
/* just work on Ethernet packets that contain IP */
|
|
if(type == ETH_P_IP && header->caplen >= ip_offset) {
|
|
frag_off = ntohs(iph->frag_off);
|
|
|
|
proto = iph->protocol;
|
|
if(header->caplen < header->len) {
|
|
static u_int8_t cap_warning_used = 0;
|
|
|
|
if(cap_warning_used == 0) {
|
|
if(!workflow->prefs.quiet_mode)
|
|
NDPI_LOG(0, workflow->ndpi_struct, NDPI_LOG_DEBUG, "\n\nWARNING: packet capture size is smaller than packet size, DETECTION MIGHT NOT WORK CORRECTLY\n\n");
|
|
cap_warning_used = 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
if(iph->version == IPVERSION) {
|
|
ip_len = ((u_int16_t)iph->ihl * 4);
|
|
iph6 = NULL;
|
|
|
|
if(iph->protocol == IPPROTO_IPV6) {
|
|
ip_offset += ip_len;
|
|
goto iph_check;
|
|
}
|
|
|
|
if((frag_off & 0x1FFF) != 0) {
|
|
static u_int8_t ipv4_frags_warning_used = 0;
|
|
workflow->stats.fragmented_count++;
|
|
|
|
if(ipv4_frags_warning_used == 0) {
|
|
if(!workflow->prefs.quiet_mode)
|
|
NDPI_LOG(0, workflow->ndpi_struct, NDPI_LOG_DEBUG, "\n\nWARNING: IPv4 fragments are not handled by this demo (nDPI supports them)\n");
|
|
ipv4_frags_warning_used = 1;
|
|
}
|
|
|
|
workflow->stats.total_discarded_bytes += header->len;
|
|
return(nproto);
|
|
}
|
|
} else if(iph->version == 6) {
|
|
iph6 = (struct ndpi_ipv6hdr *)&packet[ip_offset];
|
|
proto = iph6->ip6_hdr.ip6_un1_nxt;
|
|
ip_len = sizeof(struct ndpi_ipv6hdr);
|
|
|
|
if(proto == IPPROTO_DSTOPTS /* IPv6 destination option */) {
|
|
|
|
u_int8_t *options = (u_int8_t*)&packet[ip_offset+ip_len];
|
|
proto = options[0];
|
|
ip_len += 8 * (options[1] + 1);
|
|
}
|
|
iph = NULL;
|
|
|
|
} else {
|
|
static u_int8_t ipv4_warning_used = 0;
|
|
|
|
v4_warning:
|
|
if(ipv4_warning_used == 0) {
|
|
if(!workflow->prefs.quiet_mode)
|
|
NDPI_LOG(0, workflow->ndpi_struct, NDPI_LOG_DEBUG, "\n\nWARNING: only IPv4/IPv6 packets are supported in this demo (nDPI supports both IPv4 and IPv6), all other packets will be discarded\n\n");
|
|
ipv4_warning_used = 1;
|
|
}
|
|
workflow->stats.total_discarded_bytes += header->len;
|
|
return(nproto);
|
|
}
|
|
|
|
if(workflow->prefs.decode_tunnels && (proto == IPPROTO_UDP)) {
|
|
struct ndpi_udphdr *udp = (struct ndpi_udphdr *)&packet[ip_offset+ip_len];
|
|
u_int16_t sport = ntohs(udp->source), dport = ntohs(udp->dest);
|
|
|
|
if((sport == GTP_U_V1_PORT) || (dport == GTP_U_V1_PORT)) {
|
|
/* Check if it's GTPv1 */
|
|
u_int offset = ip_offset+ip_len+sizeof(struct ndpi_udphdr);
|
|
u_int8_t flags = packet[offset];
|
|
u_int8_t message_type = packet[offset+1];
|
|
|
|
if((((flags & 0xE0) >> 5) == 1 /* GTPv1 */) &&
|
|
(message_type == 0xFF /* T-PDU */)) {
|
|
|
|
ip_offset = ip_offset+ip_len+sizeof(struct ndpi_udphdr)+8; /* GTPv1 header len */
|
|
if(flags & 0x04) ip_offset += 1; /* next_ext_header is present */
|
|
if(flags & 0x02) ip_offset += 4; /* sequence_number is present (it also includes next_ext_header and pdu_number) */
|
|
if(flags & 0x01) ip_offset += 1; /* pdu_number is present */
|
|
|
|
iph = (struct ndpi_iphdr *) &packet[ip_offset];
|
|
|
|
if(iph->version != IPVERSION) {
|
|
// printf("WARNING: not good (packet_id=%u)!\n", (unsigned int)workflow->stats.raw_packet_count);
|
|
goto v4_warning;
|
|
}
|
|
}
|
|
} else if((sport == TZSP_PORT) || (dport == TZSP_PORT)) {
|
|
/* https://en.wikipedia.org/wiki/TZSP */
|
|
u_int offset = ip_offset+ip_len+sizeof(struct ndpi_udphdr);
|
|
u_int8_t version = packet[offset];
|
|
u_int8_t type = packet[offset+1];
|
|
u_int16_t encapsulates = ntohs(*((u_int16_t*)&packet[offset+2]));
|
|
|
|
if((version == 1) && (type == 0) && (encapsulates == 1)) {
|
|
u_int8_t stop = 0;
|
|
|
|
offset += 4;
|
|
|
|
while((!stop) && (offset < header->caplen)) {
|
|
u_int8_t tag_type = packet[offset];
|
|
u_int8_t tag_len;
|
|
|
|
switch(tag_type) {
|
|
case 0: /* PADDING Tag */
|
|
tag_len = 1;
|
|
break;
|
|
case 1: /* END Tag */
|
|
tag_len = 1, stop = 1;
|
|
break;
|
|
default:
|
|
tag_len = packet[offset+1];
|
|
break;
|
|
}
|
|
|
|
offset += tag_len;
|
|
|
|
if(offset >= header->caplen)
|
|
return(nproto); /* Invalid packet */
|
|
else {
|
|
eth_offset = offset;
|
|
goto datalink_check;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/* process the packet */
|
|
return(packet_processing(workflow, time, vlan_id, iph, iph6,
|
|
ip_offset, header->caplen - ip_offset, header->caplen));
|
|
}
|
|
|
|
/* ********************************************************** */
|
|
/* http://home.thep.lu.se/~bjorn/crc/crc32_fast.c */
|
|
/* ********************************************************** */
|
|
|
|
static uint32_t crc32_for_byte(uint32_t r) {
|
|
int j;
|
|
for(j = 0; j < 8; ++j)
|
|
r = (r & 1? 0: (uint32_t)0xEDB88320L) ^ r >> 1;
|
|
return r ^ (uint32_t)0xFF000000L;
|
|
}
|
|
|
|
/* Any unsigned integer type with at least 32 bits may be used as
|
|
* accumulator type for fast crc32-calulation, but unsigned long is
|
|
* probably the optimal choice for most systems. */
|
|
typedef unsigned long accum_t;
|
|
|
|
static void init_tables(uint32_t* table, uint32_t* wtable) {
|
|
size_t i, j, k, w;
|
|
for(i = 0; i < 0x100; ++i)
|
|
table[i] = crc32_for_byte(i);
|
|
for(k = 0; k < sizeof(accum_t); ++k)
|
|
for(i = 0; i < 0x100; ++i) {
|
|
for(j = w = 0; j < sizeof(accum_t); ++j)
|
|
w = table[(uint8_t)(j == k? w ^ i: w)] ^ w >> 8;
|
|
wtable[(k << 8) + i] = w ^ (k? wtable[0]: 0);
|
|
}
|
|
}
|
|
|
|
static void __crc32(const void* data, size_t n_bytes, uint32_t* crc) {
|
|
static uint32_t table[0x100], wtable[0x100*sizeof(accum_t)];
|
|
size_t n_accum = n_bytes/sizeof(accum_t);
|
|
size_t i, j;
|
|
if(!*table)
|
|
init_tables(table, wtable);
|
|
for(i = 0; i < n_accum; ++i) {
|
|
accum_t a = *crc ^ ((accum_t*)data)[i];
|
|
for(j = *crc = 0; j < sizeof(accum_t); ++j)
|
|
*crc ^= wtable[(j << 8) + (uint8_t)(a >> 8*j)];
|
|
}
|
|
for(i = n_accum*sizeof(accum_t); i < n_bytes; ++i)
|
|
*crc = table[(uint8_t)*crc ^ ((uint8_t*)data)[i]] ^ *crc >> 8;
|
|
}
|
|
|
|
u_int32_t ethernet_crc32(const void* data, size_t n_bytes) {
|
|
u_int32_t crc = 0;
|
|
__crc32(data, n_bytes, &crc);
|
|
return crc;
|
|
}
|