Esempio n. 1
0
static int proto_dns_process(struct proto *proto, struct packet *p, struct proto_process_stack *stack, unsigned int stack_index) {

	struct proto_process_stack *s = &stack[stack_index];
	struct proto_process_stack *s_next = &stack[stack_index + 1];

	if (s->plen < sizeof(struct dns_header))
		return PROTO_INVALID;

	struct dns_header *dhdr = s->pload;

	uint16_t qdcount = 0, ancount = 0, nscount = 0, arcount = 0;
	qdcount = ntohs(dhdr->qdcount);
	ancount = ntohs(dhdr->ancount);
	nscount = ntohs(dhdr->nscount);
	arcount = ntohs(dhdr->arcount);

	PTYPE_UINT16_SETVAL(s->pkt_info->fields_value[proto_dns_field_id], ntohs(dhdr->id));
	PTYPE_BOOL_SETVAL(s->pkt_info->fields_value[proto_dns_field_response], dhdr->qr);
	PTYPE_UINT8_SETVAL(s->pkt_info->fields_value[proto_dns_field_rcode], dhdr->rcode);
	PTYPE_UINT16_SETVAL(s->pkt_info->fields_value[proto_dns_field_qdcount], qdcount);
	PTYPE_UINT16_SETVAL(s->pkt_info->fields_value[proto_dns_field_ancount], ancount);
	PTYPE_UINT16_SETVAL(s->pkt_info->fields_value[proto_dns_field_nscount], nscount);
	PTYPE_UINT16_SETVAL(s->pkt_info->fields_value[proto_dns_field_arcount], arcount);


	if (qdcount != 1)
		return PROTO_INVALID;

	s_next->plen = s->plen - sizeof(struct dns_header);
	s_next->pload = s->pload + sizeof(struct dns_header);

	return PROTO_OK;

}
Esempio n. 2
0
static int proto_vlan_process(void *proto_priv, struct packet *p, struct proto_process_stack *stack, unsigned int stack_index) {

	struct proto_process_stack *s = &stack[stack_index];

	if (s->plen < PROTO_VLAN_HEADER_SIZE)
		return PROTO_INVALID;

	uint16_t tci = ntohs(*(uint16_t*)s->pload);
	uint16_t *ether_type = s->pload + sizeof(uint16_t);


	uint16_t de = (tci & PROTO_VLAN_DE_MASK) >> PROTO_VLAN_DE_SHIFT;
	uint16_t pcp = (tci & PROTO_VLAN_PCP_MASK) >> PROTO_VLAN_PCP_SHIFT;
	uint16_t vid = tci & PROTO_VLAN_VID_MASK;

	
	PTYPE_UINT16_SETVAL(s->pkt_info->fields_value[proto_vlan_field_vid], vid);
	PTYPE_BOOL_SETVAL(s->pkt_info->fields_value[proto_vlan_field_de], de);
	PTYPE_UINT8_SETVAL(s->pkt_info->fields_value[proto_vlan_field_pcp], pcp);

	struct proto_process_stack *s_next = &stack[stack_index + 1];

	s_next->pload = s->pload + PROTO_VLAN_HEADER_SIZE;
	s_next->plen = s->plen - PROTO_VLAN_HEADER_SIZE;

	s_next->proto = proto_get_by_number(s->proto, ntohs(*ether_type));

	return PROTO_OK;

}
Esempio n. 3
0
static int analyzer_smtp_event_process_begin(struct event *evt, void *obj, struct proto_process_stack *stack, unsigned int stack_index) {

	struct analyzer *analyzer = obj;
	struct analyzer_smtp_priv *apriv = analyzer->priv;
	struct proto_process_stack *s = &stack[stack_index];
	if (!s->ce)
		return POM_ERR;

	// Only process stuff if we have the DATA event or if we already have an event
	struct event_reg *evt_reg = event_get_reg(evt);
	struct data *evt_data = event_get_data(evt);

	struct analyzer_smtp_ce_priv *cpriv = conntrack_get_priv(s->ce, analyzer);
	
	// It's expected that an SMTP connection will always contain at least one message
	// So we always create the cpriv and event, no matter what
	if (!cpriv) {
		cpriv = malloc(sizeof(struct analyzer_smtp_ce_priv));
		if (!cpriv) {
			pom_oom(sizeof(struct analyzer_smtp_ce_priv));
			return POM_ERR;
		}
		memset(cpriv, 0, sizeof(struct analyzer_smtp_ce_priv));

		if (conntrack_add_priv(s->ce, analyzer, cpriv, analyzer_smtp_ce_priv_cleanup) != POM_OK) {
			free(cpriv);
			return POM_ERR;
		}
	}

	if (!cpriv->evt_msg) {
		cpriv->evt_msg = event_alloc(apriv->evt_msg);
		if (!cpriv->evt_msg)
			return POM_ERR;

	}


	struct data *msg_data = event_get_data(cpriv->evt_msg);
	
	if (evt_reg == apriv->evt_cmd) {

		if (!cpriv->common_data_fetched)
			analyzer_smtp_event_fetch_common_data(cpriv, stack, stack_index, POM_DIR_REVERSE(s->direction));


		// Process commands


		// A message was being transmitted and we recevied a new command
		if (event_is_started(cpriv->evt_msg)) {
			event_process_end(cpriv->evt_msg);
			cpriv->evt_msg = NULL;
		}

		char *cmd = PTYPE_STRING_GETVAL(evt_data[proto_smtp_cmd_name].value);
		if (!cmd)
			return POM_OK;

		char *arg = PTYPE_STRING_GETVAL(evt_data[proto_smtp_cmd_arg].value);
		if (arg) {
			while (*arg == ' ')
				arg++;
		}

		if (!strcasecmp(cmd, "MAIL")) {
			if (strncasecmp(arg, "FROM:", strlen("FROM:"))) {
				pomlog(POMLOG_DEBUG "Unparseable MAIL command");
				return POM_OK;
			}
			arg += strlen("FROM:");
			while (*arg == ' ')
				arg++;

			if (*arg == '<')
				arg++;

			size_t len;
			char *end = strchr(arg, '>');
			if (end)
				len = end - arg;
			else
				len = strlen(arg);

			PTYPE_STRING_SETVAL_N(msg_data[analyzer_smtp_msg_from].value, arg, len);
			data_set(msg_data[analyzer_smtp_msg_from]);
			cpriv->last_cmd = analyzer_smtp_last_cmd_mail_from;
			
		} else if (!strcasecmp(cmd, "RCPT")) {
			if (strncasecmp(arg, "TO:", strlen("TO:"))) {
				pomlog(POMLOG_DEBUG "Unparseable RCPT command");
				return POM_OK;
			}
			arg += strlen("TO:");
			while (*arg == ' ')
				arg++;

			if (*arg == '<')
				arg++;

			size_t len;
			char *end = strchr(arg, '>');
			if (end)
				len = end - arg;
			else
				len = strlen(arg);

			struct ptype *to = ptype_alloc("string");
			if (!to)
				return POM_ERR;

			PTYPE_STRING_SETVAL_N(to, arg, len);
			if (data_item_add_ptype(msg_data, analyzer_smtp_msg_to, strdup("to"), to) != POM_OK) {
				ptype_cleanup(to);
				return POM_ERR;
			}
			cpriv->last_cmd = analyzer_smtp_last_cmd_rcpt_to;

		} else if (!strcasecmp(cmd, "DATA")) {
			cpriv->last_cmd = analyzer_smtp_last_cmd_data;

			if (!event_is_started(cpriv->evt_msg)) {
				analyzer_smtp_event_fill_common_data(cpriv, msg_data);
				event_process_begin(cpriv->evt_msg, stack, stack_index, event_get_timestamp(evt));
			} else {
				pomlog(POMLOG_DEBUG "Message event already started !");
			}

		} else if (!strcasecmp(cmd, "RSET")) {
			// Cleanup the event
			event_cleanup(cpriv->evt_msg);
			cpriv->evt_msg = NULL;
			cpriv->last_cmd = analyzer_smtp_last_cmd_other;
		} else if (!strcasecmp(cmd, "HELO") || !strcasecmp(cmd, "EHLO")) {
			if (cpriv->client_hello) {
				pomlog(POMLOG_DEBUG "We already have a client hello !");
				free(cpriv->client_hello);
			}

			cpriv->client_hello = strdup(arg);
			if (!cpriv->client_hello) {
				pom_oom(strlen(arg) + 1);
				return POM_ERR;
			}
			cpriv->last_cmd = analyzer_smtp_last_cmd_other;

		} else if (!strcasecmp(cmd, "AUTH")) {
			if (!strncasecmp(arg, "PLAIN", strlen("PLAIN"))) {
				arg += strlen("PLAIN");
				while (*arg == ' ')
					arg++;


				if (cpriv->evt_auth) {
					event_process_end(cpriv->evt_auth);
					cpriv->evt_auth = NULL;
				}

				if (strlen(arg)) {
					if (analyzer_smtp_parse_auth_plain(apriv, cpriv, arg) == POM_OK) {
						event_process_begin(cpriv->evt_auth, stack, stack_index, event_get_timestamp(evt));
						cpriv->last_cmd = analyzer_smtp_last_cmd_auth_plain_creds;
					}
				} else {
					cpriv->last_cmd = analyzer_smtp_last_cmd_auth_plain;
					
				}

			} else if (!strncasecmp(arg, "LOGIN", strlen("LOGIN"))) {
				arg += strlen("LOGIN");
				while (*arg == ' ')
					arg++;

				if (cpriv->evt_auth) {
					event_process_end(cpriv->evt_auth);
					cpriv->evt_auth = NULL;
				}

				cpriv->evt_auth = event_alloc(apriv->evt_auth);
				if (!cpriv->evt_auth)
					return POM_ERR;

				struct data *auth_data = event_get_data(cpriv->evt_auth);

				analyzer_smtp_event_fill_common_data(cpriv, auth_data);

				// Set the authentication type
				PTYPE_STRING_SETVAL(auth_data[analyzer_smtp_auth_type].value, "LOGIN");
				data_set(auth_data[analyzer_smtp_auth_type]);

				if (strlen(arg)) {
					char *username = NULL;
					size_t out_len = 0;
					struct ptype *username_pt = NULL;
					if (decoder_decode_simple("base64", arg, strlen(arg), &username, &out_len) == POM_OK) {
						username_pt = ptype_alloc("string");
						if (username_pt) {
							PTYPE_STRING_SETVAL_P(username_pt, username);
							if (data_item_add_ptype(auth_data, analyzer_smtp_auth_params, strdup("username"), username_pt) != POM_OK) {
								ptype_cleanup(username_pt);
								event_cleanup(cpriv->evt_auth);
								cpriv->evt_auth = NULL;
								username_pt = NULL;
							}
						} else {
							free(username);
						}
					}

					if (!username_pt) {
						cpriv->last_cmd = analyzer_smtp_last_cmd_other;
						event_process_begin(cpriv->evt_auth, stack, stack_index, event_get_timestamp(evt));
					}
				} else {
					cpriv->last_cmd = analyzer_smtp_last_cmd_auth_login;
				}
			}

		} else if (cpriv->last_cmd == analyzer_smtp_last_cmd_auth_plain) {
			// We are expecting the credentials right now
			if (analyzer_smtp_parse_auth_plain(apriv, cpriv, cmd) == POM_OK) {
				event_process_begin(cpriv->evt_auth, stack, stack_index, event_get_timestamp(evt));
				cpriv->last_cmd = analyzer_smtp_last_cmd_auth_plain_creds;
			} else {
				cpriv->last_cmd = analyzer_smtp_last_cmd_other;
			}
		} else if (cpriv->last_cmd == analyzer_smtp_last_cmd_auth_login) {
			char *username = NULL;
			size_t out_len = 0;
			struct ptype *username_pt = NULL;
			if (decoder_decode_simple("base64", cmd, strlen(cmd), &username, &out_len) == POM_OK) {
				username_pt = ptype_alloc("string");
				if (username_pt) {
					PTYPE_STRING_SETVAL_P(username_pt, username);
					struct data *auth_data = event_get_data(cpriv->evt_auth);
					if (data_item_add_ptype(auth_data, analyzer_smtp_auth_params, strdup("username"), username_pt) != POM_OK) {
						ptype_cleanup(username_pt);
						event_process_end(cpriv->evt_auth);
						cpriv->evt_auth = NULL;
						username_pt = NULL;
					}
				} else {
					free(username);
				}
			}

			if (!username_pt) {
				cpriv->last_cmd = analyzer_smtp_last_cmd_other;
			} else {
				event_process_begin(cpriv->evt_auth, stack, stack_index, event_get_timestamp(evt));
				cpriv->last_cmd = analyzer_smtp_last_cmd_auth_login_user;
			}

		} else if (cpriv->last_cmd == analyzer_smtp_last_cmd_auth_login_user) {
			char *password = NULL;
			size_t out_len = 0;
			struct ptype *password_pt = NULL;
			if (decoder_decode_simple("base64", cmd, strlen(cmd), &password, &out_len) == POM_OK) {
				password_pt = ptype_alloc("string");
				if (password_pt) {
					PTYPE_STRING_SETVAL_P(password_pt, password);
					struct data *auth_data = event_get_data(cpriv->evt_auth);
					if (data_item_add_ptype(auth_data, analyzer_smtp_auth_params, strdup("password"), password_pt) != POM_OK) {
						ptype_cleanup(password_pt);
						event_process_end(cpriv->evt_auth);
						cpriv->evt_auth = NULL;
						password_pt = NULL;
					}
				} else {
					free(password);
				}
			}

			if (!password_pt) {
				cpriv->last_cmd = analyzer_smtp_last_cmd_other;
			} else {
				cpriv->last_cmd = analyzer_smtp_last_cmd_auth_login_pass;
			}
		} else {
			cpriv->last_cmd = analyzer_smtp_last_cmd_other;
		}

	} else if (evt_reg == apriv->evt_reply) {

		if (!cpriv->common_data_fetched)
			analyzer_smtp_event_fetch_common_data(cpriv, stack, stack_index, s->direction);

		// Process replies
		uint16_t code = *PTYPE_UINT16_GETVAL(evt_data[proto_smtp_reply_code].value);

		switch (cpriv->last_cmd) {

			default:
			case analyzer_smtp_last_cmd_other:
				if (code == 220 && evt_data[proto_smtp_reply_text].items && evt_data[proto_smtp_reply_text].items->value) {
					// STARTTLS returns 220 as well so ignore extra code 220
					if (!cpriv->server_hello) {
						char *helo = PTYPE_STRING_GETVAL(evt_data[proto_smtp_reply_text].items->value);
						cpriv->server_hello = strdup(helo);
						if (!cpriv->server_hello) {
							pom_oom(strlen(helo) + 1);
							return POM_ERR;
						}
					}
				}
				break;

			case analyzer_smtp_last_cmd_mail_from:
				if (code != 250) {
					// FROM is invalid
					data_unset(msg_data[analyzer_smtp_msg_from]);
				}
				break;
			case analyzer_smtp_last_cmd_rcpt_to:
				// For now just don't do anything
				// It's best to keep a destination in there even if it's invalid or denied
				break;
			
			case analyzer_smtp_last_cmd_data:
				if (code == 354) {
					// The message is starting, keep last_cmd intact
					return POM_OK;
				}

				// Message is over (if ever transmited)
				if (event_is_started(cpriv->evt_msg)) {
					struct data *msg_data = event_get_data(cpriv->evt_msg);
					PTYPE_UINT16_SETVAL(msg_data[analyzer_smtp_msg_result].value, code);
					data_set(msg_data[analyzer_smtp_msg_result]);
					event_process_end(cpriv->evt_msg);
					cpriv->evt_msg = NULL;
				}
				break;

			case analyzer_smtp_last_cmd_auth_plain:
			case analyzer_smtp_last_cmd_auth_login:
			case analyzer_smtp_last_cmd_auth_login_user:
				// Check if authentication phase can continue
				if (code == 334) {
					// Don't reset cpriv->last_cmd
					return POM_OK;
				} else {
					struct data *evt_data = event_get_data(cpriv->evt_auth);
					PTYPE_BOOL_SETVAL(evt_data[analyzer_smtp_auth_success].value, 0);
					data_set(evt_data[analyzer_smtp_auth_success]);
					event_process_end(cpriv->evt_auth);
					cpriv->evt_auth = NULL;
				}
				break;

			case analyzer_smtp_last_cmd_auth_plain_creds:
			case analyzer_smtp_last_cmd_auth_login_pass: {
				// We just processed the credentials
				struct data *auth_data = event_get_data(cpriv->evt_auth);
				char success = 0;
				if (code == 235)
					success = 1;
				PTYPE_BOOL_SETVAL(auth_data[analyzer_smtp_auth_success].value, success);
				data_set(auth_data[analyzer_smtp_auth_success]);
				event_process_end(cpriv->evt_auth);
				cpriv->evt_auth = NULL;
				break;
			}

		}

		cpriv->last_cmd = analyzer_smtp_last_cmd_other;

	}


	return POM_OK;
}
Esempio n. 4
0
int analyzer_ppp_pap_finalize(struct analyzer_ppp_pap_priv *apriv, struct analyzer_ppp_pap_ce_priv *cpriv) {

    if (!cpriv->evt_request)
        return POM_OK;

    struct event *evt = NULL;
    struct data *evt_data = NULL;

    struct data *evt_req_data = event_get_data(cpriv->evt_request);

    evt = event_alloc(apriv->evt_auth);
    if (!evt)
        return POM_ERR;

    evt_data = event_get_data(evt);

    if (ptype_copy(evt_data[analyzer_ppp_pap_auth_peer_id].value, evt_req_data[evt_ppp_pap_request_peer_id].value) != POM_OK) {
        event_cleanup(evt);
        return POM_ERR;
    }
    data_set(evt_data[analyzer_ppp_pap_auth_peer_id]);

    if (ptype_copy(evt_data[analyzer_ppp_pap_auth_password].value, evt_req_data[evt_ppp_pap_request_password].value) != POM_OK) {
        event_cleanup(evt);
        return POM_ERR;
    }
    data_set(evt_data[analyzer_ppp_pap_auth_password]);


    if (cpriv->client) {
        evt_data[analyzer_ppp_pap_auth_client].value = cpriv->client;
        data_set(evt_data[analyzer_ppp_pap_auth_client]);
        data_do_clean(evt_data[analyzer_ppp_pap_auth_client]);
        cpriv->client = NULL;
    }

    if (cpriv->server) {
        evt_data[analyzer_ppp_pap_auth_server].value = cpriv->server;
        data_set(evt_data[analyzer_ppp_pap_auth_server]);
        data_do_clean(evt_data[analyzer_ppp_pap_auth_server]);
        cpriv->server = NULL;
    }

    if (cpriv->vlan) {
        evt_data[analyzer_ppp_pap_auth_vlan].value = cpriv->vlan;
        data_set(evt_data[analyzer_ppp_pap_auth_vlan]);
        data_do_clean(evt_data[analyzer_ppp_pap_auth_vlan]);
        cpriv->vlan = NULL;
    }

    if (cpriv->top_proto) {
        PTYPE_STRING_SETVAL(evt_data[analyzer_ppp_pap_auth_top_proto].value, cpriv->top_proto);
        data_set(evt_data[analyzer_ppp_pap_auth_top_proto]);
    }

    if (ptype_copy(evt_data[analyzer_ppp_pap_auth_identifier].value, evt_req_data[evt_ppp_pap_request_identifier].value) != POM_OK) {
        event_cleanup(evt);
        return POM_ERR;
    }
    data_set(evt_data[analyzer_ppp_pap_auth_identifier]);

    if (cpriv->evt_ack_nack) {
        struct data *evt_ack_data = event_get_data(cpriv->evt_ack_nack);
        uint8_t code = *PTYPE_UINT8_GETVAL(evt_ack_data[evt_ppp_pap_ack_nack_code].value);

        if (code == 2) {
            PTYPE_BOOL_SETVAL(evt_data[analyzer_ppp_pap_auth_success].value, 1);
        } else {
            PTYPE_BOOL_SETVAL(evt_data[analyzer_ppp_pap_auth_success].value, 0);
        }
        data_set(evt_data[analyzer_ppp_pap_auth_success]);

        event_refcount_dec(cpriv->evt_ack_nack);
        cpriv->evt_ack_nack = NULL;
    }

    ptime ts = event_get_timestamp(cpriv->evt_request);

    event_refcount_dec(cpriv->evt_request);
    cpriv->evt_request = NULL;

    return event_process(evt, NULL, 0, ts);
}
Esempio n. 5
0
static int proto_eap_process(void *proto_priv, struct packet *p, struct proto_process_stack *stack, unsigned int stack_index) {

	struct proto_process_stack *s = &stack[stack_index];

	if (sizeof(struct eap_header) > s->plen)
		return PROTO_INVALID;

	struct proto_eap_priv *priv = proto_priv;

	struct eap_header *hdr = s->pload;

	PTYPE_UINT8_SETVAL(s->pkt_info->fields_value[proto_eap_field_code], hdr->code);
	PTYPE_UINT8_SETVAL(s->pkt_info->fields_value[proto_eap_field_identifier], hdr->identifier);

	
	if (hdr->code < 1 || hdr->code > 4)
		return PROTO_INVALID;

	uint16_t len = ntohs(hdr->length);

	if (len > s->plen)
		return PROTO_INVALID;

	// Keep only the payload lenght
	len -= sizeof(struct eap_header);
	
	if (conntrack_get(stack, stack_index) != POM_OK)
		return PROTO_ERR;

	if (conntrack_delayed_cleanup(s->ce, *PTYPE_UINT32_GETVAL(priv->p_timeout), p->ts) != POM_OK) {
		conntrack_unlock(s->ce);
		return PROTO_ERR;
	}
	conntrack_unlock(s->ce);

	if (hdr->code == 3 || hdr->code == 4) {
		// Content length is 0 for success and failure
		if (len != 4)
			return PROTO_INVALID;
		len = 0;

		if (!event_has_listener(priv->evt_success_failure))
			return PROTO_OK;

		struct event *evt = event_alloc(priv->evt_success_failure);
		if (!evt)
			return PROTO_ERR;
		struct data *evt_data = event_get_data(evt);
		PTYPE_UINT8_SETVAL(evt_data[evt_eap_common_identifier].value, hdr->identifier);
		data_set(evt_data[evt_eap_common_identifier]);
		PTYPE_BOOL_SETVAL(evt_data[evt_eap_success_failure_success].value, (hdr->code == 3 ? 1 : 0));
		data_set(evt_data[evt_eap_success_failure_success]);

		return event_process(evt, stack, stack_index, p->ts);
	}

	// At this point, code is either 1 or 2 (request/response)

	void *pload = s->pload + sizeof(struct eap_header);

	uint8_t type = 0;

	// There is at least 1 byte of data for request/response
	if (len < 1)
		return PROTO_INVALID;
	len--;

	type = *(uint8_t*)pload;
	pload++;

	struct event *evt = NULL;
	struct data *evt_data = NULL;
	
	switch (type) {
		case 1: // Identity
			
			if (!event_has_listener(priv->evt_identity))
				break;

			evt = event_alloc(priv->evt_identity);
			if (!evt)
				return PROTO_ERR;
			if (len) {
				evt_data = event_get_data(evt);
				PTYPE_STRING_SETVAL_N(evt_data[evt_eap_identity_identity].value, pload, len);
				data_set(evt_data[evt_eap_identity_identity]);
			}

			break;

		case 4: // MD5-Challenge
		
			if (!event_has_listener(priv->evt_md5_challenge))
				break;

			if (len < 17)
				return PROTO_INVALID;

			uint8_t value_size = *(uint8_t*)pload;
			if (value_size != 16)
				return PROTO_INVALID;

			pload++;
			len--;

			evt = event_alloc(priv->evt_md5_challenge);
			if (!evt)
				return PROTO_ERR;
			evt_data = event_get_data(evt);

			PTYPE_BYTES_SETLEN(evt_data[evt_eap_md5_challenge_value].value, 16);
			PTYPE_BYTES_SETVAL(evt_data[evt_eap_md5_challenge_value].value, pload);
			data_set(evt_data[evt_eap_md5_challenge_value]);
			
			if (len > 16) {
				PTYPE_STRING_SETVAL_N(evt_data[evt_eap_md5_challenge_name].value, pload + 16, len - 16);
				data_set(evt_data[evt_eap_md5_challenge_name]);
			}
			break;
	}
	
	if (evt) {
		if (!evt_data)
			evt_data = event_get_data(evt);
		PTYPE_UINT8_SETVAL(evt_data[evt_eap_common_identifier].value, hdr->identifier);
		data_set(evt_data[evt_eap_common_identifier]);
		PTYPE_UINT8_SETVAL(evt_data[evt_eap_common_code].value, hdr->code);
		data_set(evt_data[evt_eap_common_code]);

		if (event_process(evt, stack, stack_index, p->ts) != POM_OK)
			return PROTO_ERR;
	}


	return PROTO_OK;

}
Esempio n. 6
0
static int analyzer_tftp_pkt_process(void *obj, struct packet *p, struct proto_process_stack *stack, unsigned int stack_index) {

	struct analyzer_tftp_priv *priv = obj;

	struct proto_process_stack *s = &stack[stack_index];
	struct proto_process_stack *s_prev = &stack[stack_index - 1];

	uint16_t opcode = *PTYPE_UINT16_GETVAL(s_prev->pkt_info->fields_value[proto_tftp_field_opcode]);

	// Get the session
	struct conntrack_session *session = conntrack_session_get(s_prev->ce);
	if (!session)
		return POM_ERR;

	struct analyzer_tftp_session_priv *spriv = conntrack_session_get_priv(session, obj);

	if (!spriv) {
		// Add session priv if it is not done yet
		spriv = malloc(sizeof(struct analyzer_tftp_session_priv));
		if (!spriv) {
			pom_oom(sizeof(struct analyzer_tftp_session_priv));
			goto err;
		}
		memset(spriv, 0, sizeof(struct analyzer_tftp_session_priv));

		if (conntrack_session_add_priv(session, obj, spriv, analyzer_tftp_session_priv_cleanup) != POM_OK) {
			free(spriv);
			goto err;
		}
	}

	void *pload = s->pload;
	uint32_t plen = s->plen;

	switch (opcode) {
		case tftp_rrq:
		case tftp_wrq: {

			if (plen < 3)
				return POM_OK; // Invalid packet

			// Find the filename
			// The below should always be valid as proto_tftp already checked this
			char *filename = pload; 
			char *mode = memchr(filename, 0, plen - 1) + 1;

			struct analyzer_tftp_file *fq = malloc(sizeof(struct analyzer_tftp_file));
			if (!fq) {
				pom_oom(sizeof(struct analyzer_tftp_file));
				goto err;
			}
			memset(fq, 0, sizeof(struct analyzer_tftp_file));

			// Get the port on which we expect this file
			// No need to check the IP as we got the session biding
			struct proto_process_stack *s_l4 = &stack[stack_index - 2];
			unsigned int i;
			for (i = 0; !fq->port ; i++) {
				struct proto_reg_info *pinfo = proto_get_info(s_l4->proto);
				char *name = pinfo->pkt_fields[i].name;
				if (!name) {
					pomlog(POMLOG_ERR "Source port not found in RRQ/WRQ packets");
					goto err;
				}
				if (!strcmp(name, "sport")) {
					fq->port = *PTYPE_UINT16_GETVAL(s_l4->pkt_info->fields_value[i]);
					break;
				}
			}

			fq->evt = event_alloc(priv->evt_file);
			if (!fq->evt) {
				free(fq);
				goto err;
			}
			struct data *evt_data = event_get_data(fq->evt);

			PTYPE_STRING_SETVAL(evt_data[analyzer_tftp_file_filename].value, filename);
			data_set(evt_data[analyzer_tftp_file_filename]);
			PTYPE_STRING_SETVAL(evt_data[analyzer_tftp_file_mode].value, mode);
			data_set(evt_data[analyzer_tftp_file_mode]);
			PTYPE_BOOL_SETVAL(evt_data[analyzer_tftp_file_write].value, opcode == tftp_wrq);
			data_set(evt_data[analyzer_tftp_file_write]);



			fq->next = spriv->files;
			if (fq->next)
				fq->next->prev = fq;
			spriv->files = fq;
			conntrack_session_unlock(session);

			event_process_begin(fq->evt, stack, stack_index, p->ts);

			break;
		}

		case tftp_data: {

			if (plen < sizeof(uint16_t))
				return POM_OK; // Invalid packet

			struct analyzer_tftp_file *f = conntrack_get_priv(s_prev->ce, obj);
			struct data *evt_data = NULL;

			if (!f) {
				// The file is not yet associated to this connection
				// Find it in the queue
				
				struct proto_process_stack *s_l4 = &stack[stack_index - 2];
				unsigned int i;
				uint16_t sport = 0, dport = 0;
				for (i = 0; !sport || !dport ; i++) {
					struct proto_reg_info *pinfo = proto_get_info(s_l4->proto);
					char *name = pinfo->pkt_fields[i].name;
					if (!name) {
						pomlog(POMLOG_ERR "Source port not found in data packets");
						goto err;
					}
					if (!strcmp(name, "sport"))
						sport = *PTYPE_UINT16_GETVAL(s_l4->pkt_info->fields_value[i]);

					if (!strcmp(name, "dport"))
						dport = *PTYPE_UINT16_GETVAL(s_l4->pkt_info->fields_value[i]);
				}

				// Find the file in the session list
				for (f = spriv->files; ; f = f->next) {
					evt_data = event_get_data(f->evt);
					if (*PTYPE_BOOL_GETVAL(evt_data[analyzer_tftp_file_write].value)) {
						if (f->port == sport)
							break;
					} else {
						if (f->port == dport)
							break;
					}
				}

				if (!f) {
					pomlog(POMLOG_DEBUG "File not found in queued file request.");
					conntrack_session_unlock(session);
					return POM_OK;
				}
				
				// Remove the file from the queue and assign it to the conntrack
				if (f->prev)
					f->prev->next = f->next;
				else
					spriv->files = f->next;
				if (f->next)
					f->next->prev = f->prev;
				
				f->prev = NULL;
				f->next = NULL;

				// Create the payload buffer
				f->pload = pload_alloc(f->evt, PLOAD_FLAG_NEED_MAGIC);
				if (!f->pload)
					goto err;

				conntrack_add_priv(s_prev->ce, obj, f, analyzer_tftp_conntrack_priv_cleanup);
			} else {
				evt_data = event_get_data(f->evt);
			}
			conntrack_session_unlock(session);
		
			if (!f->pload) {
				pomlog(POMLOG_DEBUG "Ignoring extra packet");
				return POM_OK;
			}

			// Discard the block ID
			pload += sizeof(uint16_t);
			plen -= sizeof(uint16_t);

			if (pload_append(f->pload, pload, plen) != POM_OK)
				goto err;

			uint32_t *size = PTYPE_UINT32_GETVAL(evt_data[analyzer_tftp_file_size].value);
			*size += plen;

			if (plen < ANALYZER_TFTP_BLK_SIZE) {
				// Got last packet !
				data_set(evt_data[analyzer_tftp_file_size]);
				
				int res = pload_end(f->pload);
				res += event_process_end(f->evt);
				f->evt = NULL;	
				f->pload = NULL;
				if (res)
					goto err;
			}

			break;
		}

		case tftp_error: {
			conntrack_session_unlock(session);

			struct analyzer_tftp_file *f = conntrack_get_priv(s_prev->ce, obj);
			if (f && f->pload) {
				int res = pload_end(f->pload);
				res += event_process_end(f->evt);
				f->pload = NULL;
				f->evt = NULL;
				if (res)
					goto err;
			}
			break;
		}

		default:
			conntrack_session_unlock(session);
			break;
	}
	
	return POM_OK;

err:
	conntrack_session_unlock(session);
	return POM_ERR;
}