blob: 1a6ea288aa8296607b5ede0c81a5eaaf696ad03e [file] [log] [blame] [raw]
/* SPDX-License-Identifier: LGPL-2.1+ */
/***
This file is part of systemd.
Copyright 2016 Lennart Poettering
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 "alloc-util.h"
#include "escape.h"
#include "ether-addr-util.h"
#include "hexdecoct.h"
#include "in-addr-util.h"
#include "lldp-internal.h"
#include "lldp-neighbor.h"
#include "unaligned.h"
static void lldp_neighbor_id_hash_func(const void *p, struct siphash *state) {
const LLDPNeighborID *id = p;
siphash24_compress(id->chassis_id, id->chassis_id_size, state);
siphash24_compress(&id->chassis_id_size, sizeof(id->chassis_id_size), state);
siphash24_compress(id->port_id, id->port_id_size, state);
siphash24_compress(&id->port_id_size, sizeof(id->port_id_size), state);
}
static int lldp_neighbor_id_compare_func(const void *a, const void *b) {
const LLDPNeighborID *x = a, *y = b;
int r;
r = memcmp(x->chassis_id, y->chassis_id, MIN(x->chassis_id_size, y->chassis_id_size));
if (r != 0)
return r;
if (x->chassis_id_size < y->chassis_id_size)
return -1;
if (x->chassis_id_size > y->chassis_id_size)
return 1;
r = memcmp(x->port_id, y->port_id, MIN(x->port_id_size, y->port_id_size));
if (r != 0)
return r;
if (x->port_id_size < y->port_id_size)
return -1;
if (x->port_id_size > y->port_id_size)
return 1;
return 0;
}
const struct hash_ops lldp_neighbor_id_hash_ops = {
.hash = lldp_neighbor_id_hash_func,
.compare = lldp_neighbor_id_compare_func
};
int lldp_neighbor_prioq_compare_func(const void *a, const void *b) {
const sd_lldp_neighbor *x = a, *y = b;
if (x->until < y->until)
return -1;
if (x->until > y->until)
return 1;
return 0;
}
_public_ sd_lldp_neighbor *sd_lldp_neighbor_ref(sd_lldp_neighbor *n) {
if (!n)
return NULL;
assert(n->n_ref > 0 || n->lldp);
n->n_ref++;
return n;
}
static void lldp_neighbor_free(sd_lldp_neighbor *n) {
assert(n);
free(n->id.port_id);
free(n->id.chassis_id);
free(n->port_description);
free(n->system_name);
free(n->system_description);
free(n->chassis_id_as_string);
free(n->port_id_as_string);
free(n);
}
_public_ sd_lldp_neighbor *sd_lldp_neighbor_unref(sd_lldp_neighbor *n) {
/* Drops one reference from the neighbor. Note that the object is not freed unless it is already unlinked from
* the sd_lldp object. */
if (!n)
return NULL;
assert(n->n_ref > 0);
n->n_ref--;
if (n->n_ref <= 0 && !n->lldp)
lldp_neighbor_free(n);
return NULL;
}
sd_lldp_neighbor *lldp_neighbor_unlink(sd_lldp_neighbor *n) {
/* Removes the neighbor object from the LLDP object, and frees it if it also has no other reference. */
if (!n)
return NULL;
if (!n->lldp)
return NULL;
assert_se(hashmap_remove(n->lldp->neighbor_by_id, &n->id) == n);
assert_se(prioq_remove(n->lldp->neighbor_by_expiry, n, &n->prioq_idx) >= 0);
n->lldp = NULL;
if (n->n_ref <= 0)
lldp_neighbor_free(n);
return NULL;
}
sd_lldp_neighbor *lldp_neighbor_new(size_t raw_size) {
sd_lldp_neighbor *n;
n = malloc0(ALIGN(sizeof(sd_lldp_neighbor)) + raw_size);
if (!n)
return NULL;
n->raw_size = raw_size;
n->n_ref = 1;
return n;
}
static int parse_string(char **s, const void *q, size_t n) {
const char *p = q;
char *k;
assert(s);
assert(p || n == 0);
if (*s) {
log_lldp("Found duplicate string, ignoring field.");
return 0;
}
/* Strip trailing NULs, just to be nice */
while (n > 0 && p[n-1] == 0)
n--;
if (n <= 0) /* Ignore empty strings */
return 0;
/* Look for inner NULs */
if (memchr(p, 0, n)) {
log_lldp("Found inner NUL in string, ignoring field.");
return 0;
}
/* Let's escape weird chars, for security reasons */
k = cescape_length(p, n);
if (!k)
return -ENOMEM;
free(*s);
*s = k;
return 1;
}
int lldp_neighbor_parse(sd_lldp_neighbor *n) {
struct ether_header h;
const uint8_t *p;
size_t left;
int r;
assert(n);
if (n->raw_size < sizeof(struct ether_header)) {
log_lldp("Received truncated packet, ignoring.");
return -EBADMSG;
}
memcpy(&h, LLDP_NEIGHBOR_RAW(n), sizeof(h));
if (h.ether_type != htobe16(ETHERTYPE_LLDP)) {
log_lldp("Received packet with wrong type, ignoring.");
return -EBADMSG;
}
if (h.ether_dhost[0] != 0x01 ||
h.ether_dhost[1] != 0x80 ||
h.ether_dhost[2] != 0xc2 ||
h.ether_dhost[3] != 0x00 ||
h.ether_dhost[4] != 0x00 ||
!IN_SET(h.ether_dhost[5], 0x00, 0x03, 0x0e)) {
log_lldp("Received packet with wrong destination address, ignoring.");
return -EBADMSG;
}
memcpy(&n->source_address, h.ether_shost, sizeof(struct ether_addr));
memcpy(&n->destination_address, h.ether_dhost, sizeof(struct ether_addr));
p = (const uint8_t*) LLDP_NEIGHBOR_RAW(n) + sizeof(struct ether_header);
left = n->raw_size - sizeof(struct ether_header);
for (;;) {
uint8_t type;
uint16_t length;
if (left < 2) {
log_lldp("TLV lacks header, ignoring.");
return -EBADMSG;
}
type = p[0] >> 1;
length = p[1] + (((uint16_t) (p[0] & 1)) << 8);
p += 2, left -= 2;
if (left < length) {
log_lldp("TLV truncated, ignoring datagram.");
return -EBADMSG;
}
switch (type) {
case SD_LLDP_TYPE_END:
if (length != 0) {
log_lldp("End marker TLV not zero-sized, ignoring datagram.");
return -EBADMSG;
}
/* Note that after processing the SD_LLDP_TYPE_END left could still be > 0
* as the message may contain padding (see IEEE 802.1AB-2016, sec. 8.5.12) */
goto end_marker;
case SD_LLDP_TYPE_CHASSIS_ID:
if (length < 2 || length > 256) { /* includes the chassis subtype, hence one extra byte */
log_lldp("Chassis ID field size out of range, ignoring datagram.");
return -EBADMSG;
}
if (n->id.chassis_id) {
log_lldp("Duplicate chassis ID field, ignoring datagram.");
return -EBADMSG;
}
n->id.chassis_id = memdup(p, length);
if (!n->id.chassis_id)
return -ENOMEM;
n->id.chassis_id_size = length;
break;
case SD_LLDP_TYPE_PORT_ID:
if (length < 2 || length > 256) { /* includes the port subtype, hence one extra byte */
log_lldp("Port ID field size out of range, ignoring datagram.");
return -EBADMSG;
}
if (n->id.port_id) {
log_lldp("Duplicate port ID field, ignoring datagram.");
return -EBADMSG;
}
n->id.port_id = memdup(p, length);
if (!n->id.port_id)
return -ENOMEM;
n->id.port_id_size = length;
break;
case SD_LLDP_TYPE_TTL:
if (length != 2) {
log_lldp("TTL field has wrong size, ignoring datagram.");
return -EBADMSG;
}
if (n->has_ttl) {
log_lldp("Duplicate TTL field, ignoring datagram.");
return -EBADMSG;
}
n->ttl = unaligned_read_be16(p);
n->has_ttl = true;
break;
case SD_LLDP_TYPE_PORT_DESCRIPTION:
r = parse_string(&n->port_description, p, length);
if (r < 0)
return r;
break;
case SD_LLDP_TYPE_SYSTEM_NAME:
r = parse_string(&n->system_name, p, length);
if (r < 0)
return r;
break;
case SD_LLDP_TYPE_SYSTEM_DESCRIPTION:
r = parse_string(&n->system_description, p, length);
if (r < 0)
return r;
break;
case SD_LLDP_TYPE_SYSTEM_CAPABILITIES:
if (length != 4)
log_lldp("System capabilities field has wrong size, ignoring.");
else {
n->system_capabilities = unaligned_read_be16(p);
n->enabled_capabilities = unaligned_read_be16(p + 2);
n->has_capabilities = true;
}
break;
case SD_LLDP_TYPE_PRIVATE:
if (length < 4)
log_lldp("Found private TLV that is too short, ignoring.");
break;
}
p += length, left -= length;
}
end_marker:
if (!n->id.chassis_id || !n->id.port_id || !n->has_ttl) {
log_lldp("One or more mandatory TLV missing in datagram. Ignoring.");
return -EBADMSG;
}
n->rindex = sizeof(struct ether_header);
return 0;
}
void lldp_neighbor_start_ttl(sd_lldp_neighbor *n) {
assert(n);
if (n->ttl > 0) {
usec_t base;
/* Use the packet's timestamp if there is one known */
base = triple_timestamp_by_clock(&n->timestamp, clock_boottime_or_monotonic());
if (base <= 0 || base == USEC_INFINITY)
base = now(clock_boottime_or_monotonic()); /* Otherwise, take the current time */
n->until = usec_add(base, n->ttl * USEC_PER_SEC);
} else
n->until = 0;
if (n->lldp)
prioq_reshuffle(n->lldp->neighbor_by_expiry, n, &n->prioq_idx);
}
bool lldp_neighbor_equal(const sd_lldp_neighbor *a, const sd_lldp_neighbor *b) {
if (a == b)
return true;
if (!a || !b)
return false;
if (a->raw_size != b->raw_size)
return false;
return memcmp(LLDP_NEIGHBOR_RAW(a), LLDP_NEIGHBOR_RAW(b), a->raw_size) == 0;
}
_public_ int sd_lldp_neighbor_get_source_address(sd_lldp_neighbor *n, struct ether_addr* address) {
assert_return(n, -EINVAL);
assert_return(address, -EINVAL);
*address = n->source_address;
return 0;
}
_public_ int sd_lldp_neighbor_get_destination_address(sd_lldp_neighbor *n, struct ether_addr* address) {
assert_return(n, -EINVAL);
assert_return(address, -EINVAL);
*address = n->destination_address;
return 0;
}
_public_ int sd_lldp_neighbor_get_raw(sd_lldp_neighbor *n, const void **ret, size_t *size) {
assert_return(n, -EINVAL);
assert_return(ret, -EINVAL);
assert_return(size, -EINVAL);
*ret = LLDP_NEIGHBOR_RAW(n);
*size = n->raw_size;
return 0;
}
_public_ int sd_lldp_neighbor_get_chassis_id(sd_lldp_neighbor *n, uint8_t *type, const void **ret, size_t *size) {
assert_return(n, -EINVAL);
assert_return(type, -EINVAL);
assert_return(ret, -EINVAL);
assert_return(size, -EINVAL);
assert(n->id.chassis_id_size > 0);
*type = *(uint8_t*) n->id.chassis_id;
*ret = (uint8_t*) n->id.chassis_id + 1;
*size = n->id.chassis_id_size - 1;
return 0;
}
static int format_mac_address(const void *data, size_t sz, char **ret) {
struct ether_addr a;
char *k;
assert(data || sz <= 0);
if (sz != 7)
return 0;
memcpy(&a, (uint8_t*) data + 1, sizeof(a));
k = new(char, ETHER_ADDR_TO_STRING_MAX);
if (!k)
return -ENOMEM;
*ret = ether_addr_to_string(&a, k);
return 1;
}
static int format_network_address(const void *data, size_t sz, char **ret) {
union in_addr_union a;
int family, r;
if (sz == 6 && ((uint8_t*) data)[1] == 1) {
memcpy(&a.in, (uint8_t*) data + 2, sizeof(a.in));
family = AF_INET;
} else if (sz == 18 && ((uint8_t*) data)[1] == 2) {
memcpy(&a.in6, (uint8_t*) data + 2, sizeof(a.in6));
family = AF_INET6;
} else
return 0;
r = in_addr_to_string(family, &a, ret);
if (r < 0)
return r;
return 1;
}
_public_ int sd_lldp_neighbor_get_chassis_id_as_string(sd_lldp_neighbor *n, const char **ret) {
char *k;
int r;
assert_return(n, -EINVAL);
assert_return(ret, -EINVAL);
if (n->chassis_id_as_string) {
*ret = n->chassis_id_as_string;
return 0;
}
assert(n->id.chassis_id_size > 0);
switch (*(uint8_t*) n->id.chassis_id) {
case SD_LLDP_CHASSIS_SUBTYPE_CHASSIS_COMPONENT:
case SD_LLDP_CHASSIS_SUBTYPE_INTERFACE_ALIAS:
case SD_LLDP_CHASSIS_SUBTYPE_PORT_COMPONENT:
case SD_LLDP_CHASSIS_SUBTYPE_INTERFACE_NAME:
case SD_LLDP_CHASSIS_SUBTYPE_LOCALLY_ASSIGNED:
k = cescape_length((char*) n->id.chassis_id + 1, n->id.chassis_id_size - 1);
if (!k)
return -ENOMEM;
goto done;
case SD_LLDP_CHASSIS_SUBTYPE_MAC_ADDRESS:
r = format_mac_address(n->id.chassis_id, n->id.chassis_id_size, &k);
if (r < 0)
return r;
if (r > 0)
goto done;
break;
case SD_LLDP_CHASSIS_SUBTYPE_NETWORK_ADDRESS:
r = format_network_address(n->id.chassis_id, n->id.chassis_id_size, &k);
if (r < 0)
return r;
if (r > 0)
goto done;
break;
}
/* Generic fallback */
k = hexmem(n->id.chassis_id, n->id.chassis_id_size);
if (!k)
return -ENOMEM;
done:
*ret = n->chassis_id_as_string = k;
return 0;
}
_public_ int sd_lldp_neighbor_get_port_id(sd_lldp_neighbor *n, uint8_t *type, const void **ret, size_t *size) {
assert_return(n, -EINVAL);
assert_return(type, -EINVAL);
assert_return(ret, -EINVAL);
assert_return(size, -EINVAL);
assert(n->id.port_id_size > 0);
*type = *(uint8_t*) n->id.port_id;
*ret = (uint8_t*) n->id.port_id + 1;
*size = n->id.port_id_size - 1;
return 0;
}
_public_ int sd_lldp_neighbor_get_port_id_as_string(sd_lldp_neighbor *n, const char **ret) {
char *k;
int r;
assert_return(n, -EINVAL);
assert_return(ret, -EINVAL);
if (n->port_id_as_string) {
*ret = n->port_id_as_string;
return 0;
}
assert(n->id.port_id_size > 0);
switch (*(uint8_t*) n->id.port_id) {
case SD_LLDP_PORT_SUBTYPE_INTERFACE_ALIAS:
case SD_LLDP_PORT_SUBTYPE_PORT_COMPONENT:
case SD_LLDP_PORT_SUBTYPE_INTERFACE_NAME:
case SD_LLDP_PORT_SUBTYPE_LOCALLY_ASSIGNED:
k = cescape_length((char*) n->id.port_id + 1, n->id.port_id_size - 1);
if (!k)
return -ENOMEM;
goto done;
case SD_LLDP_PORT_SUBTYPE_MAC_ADDRESS:
r = format_mac_address(n->id.port_id, n->id.port_id_size, &k);
if (r < 0)
return r;
if (r > 0)
goto done;
break;
case SD_LLDP_PORT_SUBTYPE_NETWORK_ADDRESS:
r = format_network_address(n->id.port_id, n->id.port_id_size, &k);
if (r < 0)
return r;
if (r > 0)
goto done;
break;
}
/* Generic fallback */
k = hexmem(n->id.port_id, n->id.port_id_size);
if (!k)
return -ENOMEM;
done:
*ret = n->port_id_as_string = k;
return 0;
}
_public_ int sd_lldp_neighbor_get_ttl(sd_lldp_neighbor *n, uint16_t *ret_sec) {
assert_return(n, -EINVAL);
assert_return(ret_sec, -EINVAL);
*ret_sec = n->ttl;
return 0;
}
_public_ int sd_lldp_neighbor_get_system_name(sd_lldp_neighbor *n, const char **ret) {
assert_return(n, -EINVAL);
assert_return(ret, -EINVAL);
if (!n->system_name)
return -ENODATA;
*ret = n->system_name;
return 0;
}
_public_ int sd_lldp_neighbor_get_system_description(sd_lldp_neighbor *n, const char **ret) {
assert_return(n, -EINVAL);
assert_return(ret, -EINVAL);
if (!n->system_description)
return -ENODATA;
*ret = n->system_description;
return 0;
}
_public_ int sd_lldp_neighbor_get_port_description(sd_lldp_neighbor *n, const char **ret) {
assert_return(n, -EINVAL);
assert_return(ret, -EINVAL);
if (!n->port_description)
return -ENODATA;
*ret = n->port_description;
return 0;
}
_public_ int sd_lldp_neighbor_get_system_capabilities(sd_lldp_neighbor *n, uint16_t *ret) {
assert_return(n, -EINVAL);
assert_return(ret, -EINVAL);
if (!n->has_capabilities)
return -ENODATA;
*ret = n->system_capabilities;
return 0;
}
_public_ int sd_lldp_neighbor_get_enabled_capabilities(sd_lldp_neighbor *n, uint16_t *ret) {
assert_return(n, -EINVAL);
assert_return(ret, -EINVAL);
if (!n->has_capabilities)
return -ENODATA;
*ret = n->enabled_capabilities;
return 0;
}
_public_ int sd_lldp_neighbor_from_raw(sd_lldp_neighbor **ret, const void *raw, size_t raw_size) {
_cleanup_(sd_lldp_neighbor_unrefp) sd_lldp_neighbor *n = NULL;
int r;
assert_return(ret, -EINVAL);
assert_return(raw || raw_size <= 0, -EINVAL);
n = lldp_neighbor_new(raw_size);
if (!n)
return -ENOMEM;
memcpy(LLDP_NEIGHBOR_RAW(n), raw, raw_size);
r = lldp_neighbor_parse(n);
if (r < 0)
return r;
*ret = n;
n = NULL;
return r;
}
_public_ int sd_lldp_neighbor_tlv_rewind(sd_lldp_neighbor *n) {
assert_return(n, -EINVAL);
assert(n->raw_size >= sizeof(struct ether_header));
n->rindex = sizeof(struct ether_header);
return n->rindex < n->raw_size;
}
_public_ int sd_lldp_neighbor_tlv_next(sd_lldp_neighbor *n) {
size_t length;
assert_return(n, -EINVAL);
if (n->rindex == n->raw_size) /* EOF */
return -ESPIPE;
if (n->rindex + 2 > n->raw_size) /* Truncated message */
return -EBADMSG;
length = LLDP_NEIGHBOR_TLV_LENGTH(n);
if (n->rindex + 2 + length > n->raw_size)
return -EBADMSG;
n->rindex += 2 + length;
return n->rindex < n->raw_size;
}
_public_ int sd_lldp_neighbor_tlv_get_type(sd_lldp_neighbor *n, uint8_t *type) {
assert_return(n, -EINVAL);
assert_return(type, -EINVAL);
if (n->rindex == n->raw_size) /* EOF */
return -ESPIPE;
if (n->rindex + 2 > n->raw_size)
return -EBADMSG;
*type = LLDP_NEIGHBOR_TLV_TYPE(n);
return 0;
}
_public_ int sd_lldp_neighbor_tlv_is_type(sd_lldp_neighbor *n, uint8_t type) {
uint8_t k;
int r;
assert_return(n, -EINVAL);
r = sd_lldp_neighbor_tlv_get_type(n, &k);
if (r < 0)
return r;
return type == k;
}
_public_ int sd_lldp_neighbor_tlv_get_oui(sd_lldp_neighbor *n, uint8_t oui[3], uint8_t *subtype) {
const uint8_t *d;
size_t length;
int r;
assert_return(n, -EINVAL);
assert_return(oui, -EINVAL);
assert_return(subtype, -EINVAL);
r = sd_lldp_neighbor_tlv_is_type(n, SD_LLDP_TYPE_PRIVATE);
if (r < 0)
return r;
if (r == 0)
return -ENXIO;
length = LLDP_NEIGHBOR_TLV_LENGTH(n);
if (length < 4)
return -EBADMSG;
if (n->rindex + 2 + length > n->raw_size)
return -EBADMSG;
d = LLDP_NEIGHBOR_TLV_DATA(n);
memcpy(oui, d, 3);
*subtype = d[3];
return 0;
}
_public_ int sd_lldp_neighbor_tlv_is_oui(sd_lldp_neighbor *n, const uint8_t oui[3], uint8_t subtype) {
uint8_t k[3], st;
int r;
r = sd_lldp_neighbor_tlv_get_oui(n, k, &st);
if (r == -ENXIO)
return 0;
if (r < 0)
return r;
return memcmp(k, oui, 3) == 0 && st == subtype;
}
_public_ int sd_lldp_neighbor_tlv_get_raw(sd_lldp_neighbor *n, const void **ret, size_t *size) {
size_t length;
assert_return(n, -EINVAL);
assert_return(ret, -EINVAL);
assert_return(size, -EINVAL);
/* Note that this returns the full TLV, including the TLV header */
if (n->rindex + 2 > n->raw_size)
return -EBADMSG;
length = LLDP_NEIGHBOR_TLV_LENGTH(n);
if (n->rindex + 2 + length > n->raw_size)
return -EBADMSG;
*ret = (uint8_t*) LLDP_NEIGHBOR_RAW(n) + n->rindex;
*size = length + 2;
return 0;
}
_public_ int sd_lldp_neighbor_get_timestamp(sd_lldp_neighbor *n, clockid_t clock, uint64_t *ret) {
assert_return(n, -EINVAL);
assert_return(TRIPLE_TIMESTAMP_HAS_CLOCK(clock), -EOPNOTSUPP);
assert_return(clock_supported(clock), -EOPNOTSUPP);
assert_return(ret, -EINVAL);
if (!triple_timestamp_is_set(&n->timestamp))
return -ENODATA;
*ret = triple_timestamp_by_clock(&n->timestamp, clock);
return 0;
}