int
ctl_msg_recv(int fd, enum hmsg_type *type, void **t)
{
int n, flags = -1;
struct hmsg_header hdr;
*type = NONE; *t = NULL;
/* First, we read the header to know the size of the message */
if ((n = read(fd, &hdr, sizeof(struct hmsg_header))) == -1) {
LLOG_WARN("unable to read message header");
return -1;
}
if (n == 0)
/* Remote closed the connection. */
return -1;
if (n < sizeof(struct hmsg_header)) {
LLOG_WARNX("message received too short (%d)", n);
goto recv_error;
}
if (hdr.len > (1<<15)) {
LLOG_WARNX("message received is too large");
goto recv_error;
}
if (hdr.len == 0) {
/* No answer */
*type = hdr.type;
return 0;
}
/* Now, we read the remaining message. We need to use non-blocking stuff
* just in case the message was truncated. */
if ((*t = malloc(hdr.len)) == NULL) {
LLOG_WARNX("not enough space available for incoming message");
goto recv_error;
}
if ((flags = fcntl(fd, F_GETFL, 0)) == -1 ||
fcntl(fd, F_SETFL, flags | O_NONBLOCK) == -1) {
LLOG_WARN("unable to set socket access mode to non blocking");
goto recv_error;
}
if ((n = read(fd, *t, hdr.len)) == -1) {
if (errno == EAGAIN || errno == EWOULDBLOCK) {
LLOG_WARNX("message seems truncated");
goto recv_error;
}
LLOG_WARN("unable to read incoming request");
goto recv_error;
}
if (n != hdr.len) {
LLOG_WARNX("received message is too short (%d < %zu)",
n, hdr.len);
goto recv_error;
}
fcntl(fd, F_SETFL, flags); /* No error check */
*type = hdr.type;
return hdr.len;
recv_error:
free(*t); *t = NULL;
if (flags != -1) fcntl(fd, F_SETFL, flags);
return -1;
}
void xml_start(struct writer * w , const char * tag, const char * descr ) {
struct xml_writer_private * p = w->priv;
if (xmlTextWriterStartElement(p->xw, BAD_CAST tag) < 0)
LLOG_WARNX("cannot start '%s' element", tag);
if ( descr && (strlen(descr) > 0) ) {
if (xmlTextWriterWriteFormatAttribute(p->xw, BAD_CAST "label", "%s", descr) < 0)
LLOG_WARNX("cannot add attribute 'label' to element %s", tag);
}
}
int
ctl_msg_send_recv(int fd,
enum hmsg_type type,
void *input, struct marshal_info *input_mi,
void **output, struct marshal_info *output_mi)
{
int n, input_len = 0;
void *input_buffer = NULL;
void *serialized = NULL;
enum hmsg_type received_type;
/* Serialize */
if (input) {
input_len = marshal_serialize_(input_mi, input, &input_buffer, 0, NULL, 0);
if (input_len <= 0) {
LLOG_WARNX("unable to serialize input data");
return -1;
}
}
/* Send request */
if (ctl_msg_send(fd, type, input_buffer, input_len) == -1) {
LLOG_WARN("unable to send request");
goto send_recv_error;
}
free(input_buffer); input_buffer = NULL;
/* Receive answer */
if ((n = ctl_msg_recv(fd, &received_type, &serialized)) == -1)
goto send_recv_error;
/* Check type */
if (received_type != type) {
LLOG_WARNX("incorrect received message type (expected: %d, received: %d)",
type, received_type);
goto send_recv_error;
}
/* Unserialize */
if (output == NULL) {
free(serialized);
return 0;
}
if (n == 0) {
LLOG_WARNX("no payload available in answer");
goto send_recv_error;
}
if (marshal_unserialize_(output_mi, serialized, n, output, NULL, 0, 0) <= 0) {
LLOG_WARNX("unable to deserialize received data");
goto send_recv_error;
}
/* All done. */
return 0;
send_recv_error:
free(serialized);
free(input_buffer);
return -1;
}
static int
get_port(int s, struct lldpd_port *port, char *interface, int nb)
{
struct hmsg *h;
void *p;
if ((h = (struct hmsg *)malloc(MAX_HMSGSIZE)) == NULL)
fatal(NULL);
ctl_msg_init(h, HMSG_GET_PORT);
strlcpy((char *)&h->data, interface, IFNAMSIZ);
memcpy((char*)&h->data + IFNAMSIZ, &nb, sizeof(int));
h->hdr.len += IFNAMSIZ + sizeof(int);
if (ctl_msg_send(s, h) == -1)
fatalx("get_port: unable to send request to get port");
if (ctl_msg_recv(s, h) == -1)
fatalx("get_port: unable to receive answer to get port");
if (h->hdr.type == HMSG_NONE)
/* No port */
return -1;
p = &h->data;
if (ctl_msg_unpack_structure(STRUCT_LLDPD_PORT,
port, sizeof(struct lldpd_port), h, &p) == -1) {
LLOG_WARNX("unable to retrieve port information for %s",
interface);
fatalx("get_chassis: abort");
}
return 1;
}
void xml_finish(struct writer * w) {
struct xml_writer_private * p = w->priv;
int failed = 0;
if (xmlTextWriterEndDocument(p->xw) < 0 ) {
LLOG_WARNX("cannot finish document");
failed = 1;
}
xmlFreeTextWriter(p->xw);
if ( ! failed )
xmlSaveFileEnc("-", p->doc, MY_ENCODING);
xmlFreeDoc(p->doc);
free( w->priv );
free( w );
}
void xml_end(struct writer * w) {
struct xml_writer_private * p = w->priv;
if (xmlTextWriterEndElement(p->xw) < 0 )
LLOG_WARNX("cannot end element\n");
}
void xml_data(struct writer * w, const char * data) {
struct xml_writer_private * p = w->priv;
if (xmlTextWriterWriteString(p->xw, BAD_CAST data) < 0 )
LLOG_WARNX("cannot add '%s' as data to element", data);
}
void xml_attr(struct writer * w, const char * tag, const char * descr, const char * value ) {
struct xml_writer_private * p = w->priv;
if (xmlTextWriterWriteFormatAttribute(p->xw, BAD_CAST tag, "%s", value) < 0)
LLOG_WARNX("cannot add attribute %s with value %s", tag, value);
}
/* cdp_decode also decodes FDP */
int
cdp_decode(struct lldpd *cfg, char *frame, int s,
struct lldpd_hardware *hardware,
struct lldpd_chassis **newchassis, struct lldpd_port **newport)
{
struct lldpd_chassis *chassis;
struct lldpd_port *port;
#if 0
u_int16_t cksum;
#endif
u_int8_t *software = NULL, *platform = NULL;
int software_len = 0, platform_len = 0, proto, version, nb, caps;
const unsigned char cdpaddr[] = CDP_MULTICAST_ADDR;
#ifdef ENABLE_FDP
const unsigned char fdpaddr[] = CDP_MULTICAST_ADDR;
int fdp = 0;
#endif
u_int8_t *pos, *tlv, *pos_address, *pos_next_address;
int length, len_eth, tlv_type, tlv_len, addresses_len, address_len;
if ((chassis = calloc(1, sizeof(struct lldpd_chassis))) == NULL) {
LLOG_WARN("failed to allocate remote chassis");
return -1;
}
if ((port = calloc(1, sizeof(struct lldpd_port))) == NULL) {
LLOG_WARN("failed to allocate remote port");
free(chassis);
return -1;
}
#ifdef ENABLE_DOT1
TAILQ_INIT(&port->p_vlans);
#endif
length = s;
pos = (u_int8_t*)frame;
if (length < 2*ETH_ALEN + sizeof(u_int16_t) /* Ethernet */ +
8 /* LLC */ + 4 /* CDP header */) {
LLOG_WARNX("too short CDP/FDP frame received on %s", hardware->h_ifname);
goto malformed;
}
if (PEEK_CMP(cdpaddr, sizeof(cdpaddr)) != 0) {
#ifdef ENABLE_FDP
PEEK_RESTORE((u_int8_t*)frame);
if (PEEK_CMP(fdpaddr, sizeof(fdpaddr)) != 0)
fdp = 1;
else {
#endif
LLOG_INFO("frame not targeted at CDP/FDP multicast address received on %s",
hardware->h_ifname);
goto malformed;
#ifdef ENABLE_FDP
}
#endif
}
PEEK_DISCARD(ETH_ALEN); /* Don't care of source address */
len_eth = PEEK_UINT16;
if (len_eth > length) {
LLOG_WARNX("incorrect 802.3 frame size reported on %s",
hardware->h_ifname);
goto malformed;
}
PEEK_DISCARD(6); /* Skip beginning of LLC */
proto = PEEK_UINT16;
if (proto != LLC_PID_CDP) {
if ((proto != LLC_PID_DRIP) &&
(proto != LLC_PID_PAGP) &&
(proto != LLC_PID_PVSTP) &&
(proto != LLC_PID_UDLD) &&
(proto != LLC_PID_VTP) &&
(proto != LLC_PID_DTP) &&
(proto != LLC_PID_STP))
LLOG_DEBUG("incorrect LLC protocol ID received on %s",
hardware->h_ifname);
goto malformed;
}
#if 0
/* Check checksum */
cksum = frame_checksum(pos, len_eth - 8,
#ifdef ENABLE_FDP
!fdp /* fdp = 0 -> cisco checksum */
#else
1 /* cisco checksum */
#endif
);
/* An off-by-one error may happen. Just ignore it */
if ((cksum != 0) && (cksum != 0xfffe)) {
LLOG_INFO("incorrect CDP/FDP checksum for frame received on %s (%d)",
hardware->h_ifname, cksum);
goto malformed;
}
#endif
/* Check version */
version = PEEK_UINT8;
if ((version != 1) && (version != 2)) {
LLOG_WARNX("incorrect CDP/FDP version (%d) for frame received on %s",
version, hardware->h_ifname);
goto malformed;
}
chassis->c_ttl = PEEK_UINT8; /* TTL */
PEEK_DISCARD_UINT16; /* Checksum, already checked */
while (length) {
if (length < 4) {
LLOG_WARNX("CDP/FDP TLV header is too large for "
"frame received on %s",
hardware->h_ifname);
goto malformed;
}
tlv_type = PEEK_UINT16;
tlv_len = PEEK_UINT16 - 4;
PEEK_SAVE(tlv);
if ((tlv_len < 0) || (length < tlv_len)) {
LLOG_WARNX("incorrect size in CDP/FDP TLV header for frame "
"received on %s",
hardware->h_ifname);
goto malformed;
}
switch (tlv_type) {
case CDP_TLV_CHASSIS:
if ((chassis->c_name = (char *)calloc(1, tlv_len + 1)) == NULL) {
LLOG_WARN("unable to allocate memory for chassis name");
goto malformed;
}
PEEK_BYTES(chassis->c_name, tlv_len);
chassis->c_id_subtype = LLDP_CHASSISID_SUBTYPE_LOCAL;
if ((chassis->c_id = (char *)malloc(tlv_len)) == NULL) {
LLOG_WARN("unable to allocate memory for chassis ID");
goto malformed;
}
memcpy(chassis->c_id, chassis->c_name, tlv_len);
chassis->c_id_len = tlv_len;
break;
case CDP_TLV_ADDRESSES:
CHECK_TLV_SIZE(4, "Address");
addresses_len = tlv_len - 4;
for (nb = PEEK_UINT32; nb > 0; nb--) {
PEEK_SAVE(pos_address);
/* We first try to get the real length of the packet */
if (addresses_len < 2) {
LLOG_WARN("too short address subframe "
"received on %s",
hardware->h_ifname);
goto malformed;
}
PEEK_DISCARD_UINT8; addresses_len--;
address_len = PEEK_UINT8; addresses_len--;
if (addresses_len < address_len + 2) {
LLOG_WARN("too short address subframe "
"received on %s",
hardware->h_ifname);
goto malformed;
}
PEEK_DISCARD(address_len);
addresses_len -= address_len;
address_len = PEEK_UINT16; addresses_len -= 2;
if (addresses_len < address_len) {
LLOG_WARN("too short address subframe "
"received on %s",
hardware->h_ifname);
goto malformed;
}
PEEK_DISCARD(address_len);
PEEK_SAVE(pos_next_address);
/* Next, we go back and try to extract
IPv4 address */
PEEK_RESTORE(pos_address);
if ((PEEK_UINT8 == 1) && (PEEK_UINT8 == 1) &&
(PEEK_UINT8 == CDP_ADDRESS_PROTO_IP) &&
(PEEK_UINT16 == sizeof(struct in_addr)) &&
(chassis->c_mgmt.s_addr == INADDR_ANY))
PEEK_BYTES(&chassis->c_mgmt,
sizeof(struct in_addr));
/* Go to the end of the address */
PEEK_RESTORE(pos_next_address);
}
break;
case CDP_TLV_PORT:
if ((port->p_descr = (char *)calloc(1, tlv_len + 1)) == NULL) {
LLOG_WARN("unable to allocate memory for port description");
goto malformed;
}
PEEK_BYTES(port->p_descr, tlv_len);
port->p_id_subtype = LLDP_PORTID_SUBTYPE_IFNAME;
if ((port->p_id = (char *)calloc(1, tlv_len)) == NULL) {
LLOG_WARN("unable to allocate memory for port ID");
goto malformed;
}
memcpy(port->p_id, port->p_descr, tlv_len);
port->p_id_len = tlv_len;
break;
case CDP_TLV_CAPABILITIES:
#ifdef ENABLE_FDP
if (fdp) {
/* Capabilities are string with FDP */
if (!strncmp("Router", (char*)pos, tlv_len))
chassis->c_cap_enabled = LLDP_CAP_ROUTER;
else if (!strncmp("Switch", (char*)pos, tlv_len))
chassis->c_cap_enabled = LLDP_CAP_BRIDGE;
else if (!strncmp("Bridge", (char*)pos, tlv_len))
chassis->c_cap_enabled = LLDP_CAP_REPEATER;
else
chassis->c_cap_enabled = LLDP_CAP_STATION;
chassis->c_cap_available = chassis->c_cap_enabled;
break;
}
#endif
CHECK_TLV_SIZE(4, "Capabilities");
caps = PEEK_UINT32;
if (caps & CDP_CAP_ROUTER)
chassis->c_cap_enabled |= LLDP_CAP_ROUTER;
if (caps & 0x0e)
chassis->c_cap_enabled |= LLDP_CAP_BRIDGE;
if (chassis->c_cap_enabled == 0)
chassis->c_cap_enabled = LLDP_CAP_STATION;
chassis->c_cap_available = chassis->c_cap_enabled;
break;
case CDP_TLV_SOFTWARE:
software_len = tlv_len;
PEEK_SAVE(software);
break;
case CDP_TLV_PLATFORM:
platform_len = tlv_len;
PEEK_SAVE(platform);
break;
default:
LLOG_DEBUG("unknown CDP/FDP TLV type (%d) received on %s",
ntohs(tlv_type), hardware->h_ifname);
hardware->h_rx_unrecognized_cnt++;
}
PEEK_DISCARD(tlv + tlv_len - pos);
}
if (!software && platform) {
if ((chassis->c_descr = (char *)calloc(1,
platform_len + 1)) == NULL) {
LLOG_WARN("unable to allocate memory for chassis description");
goto malformed;
}
memcpy(chassis->c_descr, platform, platform_len);
} else if (software && !platform) {
if ((chassis->c_descr = (char *)calloc(1,
software_len + 1)) == NULL) {
LLOG_WARN("unable to allocate memory for chassis description");
goto malformed;
}
memcpy(chassis->c_descr, software, software_len);
} else if (software && platform) {
#define CONCAT_PLATFORM " running on\n"
if ((chassis->c_descr = (char *)calloc(1,
software_len + platform_len +
strlen(CONCAT_PLATFORM) + 1)) == NULL) {
LLOG_WARN("unable to allocate memory for chassis description");
goto malformed;
}
memcpy(chassis->c_descr, platform, platform_len);
memcpy(chassis->c_descr + platform_len,
CONCAT_PLATFORM, strlen(CONCAT_PLATFORM));
memcpy(chassis->c_descr + platform_len + strlen(CONCAT_PLATFORM),
software, software_len);
}
if ((chassis->c_id == NULL) ||
(port->p_id == NULL) ||
(chassis->c_name == NULL) ||
(chassis->c_descr == NULL) ||
(port->p_descr == NULL) ||
(chassis->c_ttl == 0) ||
(chassis->c_cap_enabled == 0)) {
LLOG_WARNX("some mandatory CDP/FDP tlv are missing for frame received on %s",
hardware->h_ifname);
goto malformed;
}
*newchassis = chassis;
*newport = port;
return 1;
malformed:
lldpd_chassis_cleanup(chassis, 1);
lldpd_port_cleanup(cfg, port, 1);
free(port);
return -1;
}
