int dhcp_identifier_set_duid_en(struct duid *duid, size_t *len) {
sd_id128_t machine_id;
int r;
assert(duid);
assert(len);
r = sd_id128_get_machine(&machine_id);
if (r < 0)
return r;
unaligned_write_be16(&duid->type, DHCP6_DUID_EN);
unaligned_write_be32(&duid->en.pen, SYSTEMD_PEN);
*len = sizeof(duid->type) + sizeof(duid->en);
/* a bit of snake-oil perhaps, but no need to expose the machine-id
directly */
siphash24(duid->en.id, &machine_id, sizeof(machine_id), HASH_KEY.bytes);
return 0;
}
int dhcp_identifier_set_duid_en(struct duid *duid, size_t *len) {
sd_id128_t machine_id;
uint64_t hash;
int r;
assert(duid);
assert(len);
r = sd_id128_get_machine(&machine_id);
if (r < 0)
return r;
unaligned_write_be16(&duid->type, DUID_TYPE_EN);
unaligned_write_be32(&duid->en.pen, SYSTEMD_PEN);
*len = sizeof(duid->type) + sizeof(duid->en);
/* a bit of snake-oil perhaps, but no need to expose the machine-id
directly; duid->en.id might not be aligned, so we need to copy */
hash = htole64(siphash24(&machine_id, sizeof(machine_id), HASH_KEY.bytes));
memcpy(duid->en.id, &hash, sizeof(duid->en.id));
return 0;
}
static void test_be(void) {
uint8_t scratch[16];
assert_se(unaligned_read_be16(&data[0]) == 0x0001);
assert_se(unaligned_read_be16(&data[1]) == 0x0102);
assert_se(unaligned_read_be32(&data[0]) == 0x00010203);
assert_se(unaligned_read_be32(&data[1]) == 0x01020304);
assert_se(unaligned_read_be32(&data[2]) == 0x02030405);
assert_se(unaligned_read_be32(&data[3]) == 0x03040506);
assert_se(unaligned_read_be64(&data[0]) == 0x0001020304050607);
assert_se(unaligned_read_be64(&data[1]) == 0x0102030405060708);
assert_se(unaligned_read_be64(&data[2]) == 0x0203040506070809);
assert_se(unaligned_read_be64(&data[3]) == 0x030405060708090a);
assert_se(unaligned_read_be64(&data[4]) == 0x0405060708090a0b);
assert_se(unaligned_read_be64(&data[5]) == 0x05060708090a0b0c);
assert_se(unaligned_read_be64(&data[6]) == 0x060708090a0b0c0d);
assert_se(unaligned_read_be64(&data[7]) == 0x0708090a0b0c0d0e);
zero(scratch);
unaligned_write_be16(&scratch[0], 0x0001);
assert_se(memcmp(&scratch[0], &data[0], sizeof(uint16_t)) == 0);
zero(scratch);
unaligned_write_be16(&scratch[1], 0x0102);
assert_se(memcmp(&scratch[1], &data[1], sizeof(uint16_t)) == 0);
zero(scratch);
unaligned_write_be32(&scratch[0], 0x00010203);
assert_se(memcmp(&scratch[0], &data[0], sizeof(uint32_t)) == 0);
zero(scratch);
unaligned_write_be32(&scratch[1], 0x01020304);
assert_se(memcmp(&scratch[1], &data[1], sizeof(uint32_t)) == 0);
zero(scratch);
unaligned_write_be32(&scratch[2], 0x02030405);
assert_se(memcmp(&scratch[2], &data[2], sizeof(uint32_t)) == 0);
zero(scratch);
unaligned_write_be32(&scratch[3], 0x03040506);
assert_se(memcmp(&scratch[3], &data[3], sizeof(uint32_t)) == 0);
zero(scratch);
unaligned_write_be64(&scratch[0], 0x0001020304050607);
assert_se(memcmp(&scratch[0], &data[0], sizeof(uint64_t)) == 0);
zero(scratch);
unaligned_write_be64(&scratch[1], 0x0102030405060708);
assert_se(memcmp(&scratch[1], &data[1], sizeof(uint64_t)) == 0);
zero(scratch);
unaligned_write_be64(&scratch[2], 0x0203040506070809);
assert_se(memcmp(&scratch[2], &data[2], sizeof(uint64_t)) == 0);
zero(scratch);
unaligned_write_be64(&scratch[3], 0x030405060708090a);
assert_se(memcmp(&scratch[3], &data[3], sizeof(uint64_t)) == 0);
zero(scratch);
unaligned_write_be64(&scratch[4], 0x0405060708090a0b);
assert_se(memcmp(&scratch[4], &data[4], sizeof(uint64_t)) == 0);
zero(scratch);
unaligned_write_be64(&scratch[5], 0x05060708090a0b0c);
assert_se(memcmp(&scratch[5], &data[5], sizeof(uint64_t)) == 0);
zero(scratch);
unaligned_write_be64(&scratch[6], 0x060708090a0b0c0d);
assert_se(memcmp(&scratch[6], &data[6], sizeof(uint64_t)) == 0);
zero(scratch);
unaligned_write_be64(&scratch[7], 0x0708090a0b0c0d0e);
assert_se(memcmp(&scratch[7], &data[7], sizeof(uint64_t)) == 0);
}
static int lldp_make_packet(
LLDPEmit mode,
const struct ether_addr *hwaddr,
const char *machine_id,
const char *ifname,
uint16_t ttl,
const char *port_description,
const char *hostname,
const char *pretty_hostname,
uint16_t system_capabilities,
uint16_t enabled_capabilities,
void **ret, size_t *sz) {
size_t machine_id_length, ifname_length, port_description_length = 0, hostname_length = 0, pretty_hostname_length = 0;
_cleanup_free_ void *packet = NULL;
struct ether_header *h;
uint8_t *p;
size_t l;
int r;
assert(mode > LLDP_EMIT_NO);
assert(mode < _LLDP_EMIT_MAX);
assert(hwaddr);
assert(machine_id);
assert(ifname);
assert(ret);
assert(sz);
machine_id_length = strlen(machine_id);
ifname_length = strlen(ifname);
if (port_description)
port_description_length = strlen(port_description);
if (hostname)
hostname_length = strlen(hostname);
if (pretty_hostname)
pretty_hostname_length = strlen(pretty_hostname);
l = sizeof(struct ether_header) +
/* Chassis ID */
2 + 1 + machine_id_length +
/* Port ID */
2 + 1 + ifname_length +
/* TTL */
2 + 2 +
/* System Capabilities */
2 + 4 +
/* End */
2;
/* Port Description */
if (port_description)
l += 2 + port_description_length;
/* System Name */
if (hostname)
l += 2 + hostname_length;
/* System Description */
if (pretty_hostname)
l += 2 + pretty_hostname_length;
packet = malloc(l);
if (!packet)
return -ENOMEM;
h = (struct ether_header*) packet;
h->ether_type = htobe16(ETHERTYPE_LLDP);
memcpy(h->ether_dhost, lldp_multicast_addr + mode, ETH_ALEN);
memcpy(h->ether_shost, hwaddr, ETH_ALEN);
p = (uint8_t*) packet + sizeof(struct ether_header);
r = lldp_write_tlv_header(&p, SD_LLDP_TYPE_CHASSIS_ID, 1 + machine_id_length);
if (r < 0)
return r;
*(p++) = SD_LLDP_CHASSIS_SUBTYPE_LOCALLY_ASSIGNED;
p = mempcpy(p, machine_id, machine_id_length);
r = lldp_write_tlv_header(&p, SD_LLDP_TYPE_PORT_ID, 1 + ifname_length);
if (r < 0)
return r;
*(p++) = SD_LLDP_PORT_SUBTYPE_INTERFACE_NAME;
p = mempcpy(p, ifname, ifname_length);
r = lldp_write_tlv_header(&p, SD_LLDP_TYPE_TTL, 2);
if (r < 0)
return r;
unaligned_write_be16(p, ttl);
p += 2;
if (port_description) {
r = lldp_write_tlv_header(&p, SD_LLDP_TYPE_PORT_DESCRIPTION, port_description_length);
if (r < 0)
return r;
p = mempcpy(p, port_description, port_description_length);
}
if (hostname) {
r = lldp_write_tlv_header(&p, SD_LLDP_TYPE_SYSTEM_NAME, hostname_length);
if (r < 0)
return r;
p = mempcpy(p, hostname, hostname_length);
}
if (pretty_hostname) {
r = lldp_write_tlv_header(&p, SD_LLDP_TYPE_SYSTEM_DESCRIPTION, pretty_hostname_length);
if (r < 0)
return r;
p = mempcpy(p, pretty_hostname, pretty_hostname_length);
}
r = lldp_write_tlv_header(&p, SD_LLDP_TYPE_SYSTEM_CAPABILITIES, 4);
if (r < 0)
return r;
unaligned_write_be16(p, system_capabilities);
p += 2;
unaligned_write_be16(p, enabled_capabilities);
p += 2;
r = lldp_write_tlv_header(&p, SD_LLDP_TYPE_END, 0);
if (r < 0)
return r;
assert(p == (uint8_t*) packet + l);
*ret = packet;
*sz = l;
packet = NULL;
return 0;
}
