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/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright (C) 2014 Tom Gundersen
Copyright (C) 2014 Susant Sahani
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <stdio.h>
#include <string.h>
#include <net/ethernet.h>
#include <arpa/inet.h>
#include "macro.h"
#include "lldp.h"
#include "lldp-tlv.h"
#define TEST_LLDP_PORT "em1"
#define TEST_LLDP_TYPE_SYSTEM_NAME "systemd-lldp"
#define TEST_LLDP_TYPE_SYSTEM_DESC "systemd-lldp-desc"
static struct ether_addr mac_addr = {
.ether_addr_octet = {'A', 'B', 'C', '1', '2', '3'}
};
static int lldp_build_tlv_packet(tlv_packet **ret) {
_cleanup_tlv_packet_free_ tlv_packet *m = NULL;
const uint8_t lldp_dst[] = LLDP_MULTICAST_ADDR;
struct ether_header ether = {
.ether_type = htons(ETHERTYPE_LLDP),
};
/* Append ethernet header */
memcpy(ðer.ether_dhost, lldp_dst, ETHER_ADDR_LEN);
memcpy(ðer.ether_shost, &mac_addr, ETHER_ADDR_LEN);
assert_se(tlv_packet_new(&m) >= 0);
assert_se(tlv_packet_append_bytes(m, ðer, sizeof(struct ether_header)) >= 0);
assert_se(lldp_tlv_packet_open_container(m, LLDP_TYPE_CHASSIS_ID) >= 0);
assert_se(tlv_packet_append_u8(m, LLDP_CHASSIS_SUBTYPE_MAC_ADDRESS) >= 0);
assert_se(tlv_packet_append_bytes(m, &mac_addr, ETHER_ADDR_LEN) >= 0);
assert_se(lldp_tlv_packet_close_container(m) >= 0);
/* port name */
assert_se(lldp_tlv_packet_open_container(m, LLDP_TYPE_PORT_ID) >= 0);
assert_se(tlv_packet_append_u8(m, LLDP_PORT_SUBTYPE_INTERFACE_NAME) >= 0);
assert_se(tlv_packet_append_bytes(m, TEST_LLDP_PORT, strlen(TEST_LLDP_PORT) + 1) >= 0);
assert_se(lldp_tlv_packet_close_container(m) >= 0);
/* ttl */
assert_se(lldp_tlv_packet_open_container(m, LLDP_TYPE_TTL) >= 0);
assert_se(tlv_packet_append_u16(m, 170) >= 0);
assert_se(lldp_tlv_packet_close_container(m) >= 0);
/* system name */
assert_se(lldp_tlv_packet_open_container(m, LLDP_TYPE_SYSTEM_NAME) >= 0);
assert_se(tlv_packet_append_bytes(m, TEST_LLDP_TYPE_SYSTEM_NAME,
strlen(TEST_LLDP_TYPE_SYSTEM_NAME)) >= 0);
assert_se(lldp_tlv_packet_close_container(m) >= 0);
/* system descrition */
assert_se(lldp_tlv_packet_open_container(m, LLDP_TYPE_SYSTEM_DESCRIPTION) >= 0);
assert_se(tlv_packet_append_bytes(m, TEST_LLDP_TYPE_SYSTEM_DESC,
strlen(TEST_LLDP_TYPE_SYSTEM_DESC)) >= 0);
assert_se(lldp_tlv_packet_close_container(m) >= 0);
/* Mark end of packet */
assert_se(lldp_tlv_packet_open_container(m, LLDP_TYPE_END) >= 0);
assert_se(lldp_tlv_packet_close_container(m) >= 0);
*ret = m;
m = NULL;
return 0;
}
static int lldp_parse_chassis_tlv(tlv_packet *m, uint8_t *type) {
uint8_t *p, subtype;
uint16_t length;
assert_se(lldp_tlv_packet_enter_container(m, LLDP_TYPE_CHASSIS_ID) >= 0);
assert_se(tlv_packet_read_u8(m, &subtype) >= 0);
switch (subtype) {
case LLDP_CHASSIS_SUBTYPE_MAC_ADDRESS:
*type = LLDP_CHASSIS_SUBTYPE_MAC_ADDRESS;
assert_se(tlv_packet_read_bytes(m, &p, &length) >= 0);
assert_se(memcmp(p, &mac_addr.ether_addr_octet, ETHER_ADDR_LEN) == 0);
break;
default:
assert_not_reached("Unhandled option");
}
assert_se(lldp_tlv_packet_exit_container(m) >= 0);
return 0;
}
static int lldp_parse_port_id_tlv(tlv_packet *m) {
_cleanup_free_ char *p = NULL;
char *str = NULL;
uint16_t length;
uint8_t subtype;
assert_se(lldp_tlv_packet_enter_container(m, LLDP_TYPE_PORT_ID) >= 0);
assert_se(tlv_packet_read_u8(m, &subtype) >= 0);
switch (subtype) {
case LLDP_PORT_SUBTYPE_INTERFACE_NAME:
assert_se(tlv_packet_read_string(m, &str, &length) >= 0);
p = strndup(str, length-1);
assert_se(p);
assert_se(streq(p, TEST_LLDP_PORT) == 1);
break;
default:
assert_not_reached("Unhandled option");
}
assert_se(lldp_tlv_packet_exit_container(m) >= 0);
return 0;
}
static int lldp_parse_system_name_tlv(tlv_packet *m) {
_cleanup_free_ char *p = NULL;
char *str = NULL;
uint16_t length;
assert_se(lldp_tlv_packet_enter_container(m, LLDP_TYPE_SYSTEM_NAME) >= 0);
assert_se(tlv_packet_read_string(m, &str, &length) >= 0);
p = strndup(str, length);
assert_se(p);
assert_se(streq(p, TEST_LLDP_TYPE_SYSTEM_NAME) == 1);
assert_se(lldp_tlv_packet_exit_container(m) >= 0);
return 1;
}
static int lldp_parse_system_desc_tlv(tlv_packet *m) {
_cleanup_free_ char *p = NULL;
char *str = NULL;
uint16_t length;
assert_se(lldp_tlv_packet_enter_container(m, LLDP_TYPE_SYSTEM_DESCRIPTION) >= 0);
assert_se(tlv_packet_read_string(m, &str, &length) >= 0);
p = strndup(str, length);
assert_se(p);
assert_se(streq(p, TEST_LLDP_TYPE_SYSTEM_DESC) == 1);
assert_se(lldp_tlv_packet_exit_container(m) >= 0);
return 0;
}
static int lldp_parse_ttl_tlv(tlv_packet *m) {
uint16_t ttl;
assert_se(lldp_tlv_packet_enter_container(m, LLDP_TYPE_TTL) >= 0);
assert_se(tlv_packet_read_u16(m, &ttl) >= 0);
assert_se(ttl == 170);
assert_se(lldp_tlv_packet_exit_container(m) >= 0);
return 0;
}
static int lldp_parse_tlv_packet(tlv_packet *m, int len) {
uint8_t subtype;
assert_se(tlv_packet_parse_pdu(m, len) >= 0);
assert_se(lldp_parse_chassis_tlv(m, &subtype) >= 0);
assert_se(lldp_parse_port_id_tlv(m) >= 0);
assert_se(lldp_parse_system_name_tlv(m) >= 0);
assert_se(lldp_parse_ttl_tlv(m) >= 0);
assert_se(lldp_parse_system_desc_tlv(m) >= 0);
return 0;
}
int main(int argc, char *argv[]) {
_cleanup_tlv_packet_free_ tlv_packet *tlv = NULL;
/* form a packet */
lldp_build_tlv_packet(&tlv);
/* parse the packet */
tlv_packet_parse_pdu(tlv, tlv->length);
/* verify */
lldp_parse_tlv_packet(tlv, tlv->length);
return 0;
}
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