NetBSD/external/bsd/libpcap/dist/rpcap-protocol.c

199 lines
6.8 KiB
C

/*
* Copyright (c) 2002 - 2005 NetGroup, Politecnico di Torino (Italy)
* Copyright (c) 2005 - 2008 CACE Technologies, Davis (California)
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Politecnico di Torino, CACE Technologies
* nor the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <string.h> /* for strlen(), ... */
#include <stdlib.h> /* for malloc(), free(), ... */
#include <stdarg.h> /* for functions with variable number of arguments */
#include <errno.h> /* for the errno variable */
#include "sockutils.h"
#include "rpcap-protocol.h"
#include <pcap/pcap.h>
#include "portability.h"
/*
* This file contains functions used both by the rpcap client and the
* rpcap daemon.
*/
/*
* This function sends a RPCAP error to our peer.
*
* It has to be called when the main program detects an error.
* It will send to our peer the 'buffer' specified by the user.
* This function *does not* request a RPCAP CLOSE connection. A CLOSE
* command must be sent explicitly by the program, since we do not know
* whether the error can be recovered in some way or if it is a
* non-recoverable one.
*
* \param sock: the socket we are currently using.
*
* \param ssl: if compiled with openssl, the optional ssl handler to use with the above socket.
*
* \param ver: the protocol version we want to put in the reply.
*
* \param errcode: a integer which tells the other party the type of error
* we had.
*
* \param error: an user-allocated (and '0' terminated) buffer that contains
* the error description that has to be transmitted to our peer. The
* error message cannot be longer than PCAP_ERRBUF_SIZE.
*
* \param errbuf: a pointer to a user-allocated buffer (of size
* PCAP_ERRBUF_SIZE) that will contain the error message (in case there
* is one). It could be network problem.
*
* \return '0' if everything is fine, '-1' if some errors occurred. The
* error message is returned in the 'errbuf' variable.
*/
int
rpcap_senderror(SOCKET sock, SSL *ssl, uint8 ver, unsigned short errcode, const char *error, char *errbuf)
{
char sendbuf[RPCAP_NETBUF_SIZE]; /* temporary buffer in which data to be sent is buffered */
int sendbufidx = 0; /* index which keeps the number of bytes currently buffered */
uint16 length;
length = (uint16)strlen(error);
if (length > PCAP_ERRBUF_SIZE)
length = PCAP_ERRBUF_SIZE;
rpcap_createhdr((struct rpcap_header *) sendbuf, ver, RPCAP_MSG_ERROR, errcode, length);
if (sock_bufferize(NULL, sizeof(struct rpcap_header), NULL, &sendbufidx,
RPCAP_NETBUF_SIZE, SOCKBUF_CHECKONLY, errbuf, PCAP_ERRBUF_SIZE))
return -1;
if (sock_bufferize(error, length, sendbuf, &sendbufidx,
RPCAP_NETBUF_SIZE, SOCKBUF_BUFFERIZE, errbuf, PCAP_ERRBUF_SIZE))
return -1;
if (sock_send(sock, ssl, sendbuf, sendbufidx, errbuf, PCAP_ERRBUF_SIZE) < 0)
return -1;
return 0;
}
/*
* This function fills in a structure of type rpcap_header.
*
* It is provided just because the creation of an rpcap header is a common
* task. It accepts all the values that appears into an rpcap_header, and
* it puts them in place using the proper hton() calls.
*
* \param header: a pointer to a user-allocated buffer which will contain
* the serialized header, ready to be sent on the network.
*
* \param ver: a value (in the host byte order) which will be placed into the
* header.ver field and that represents the protocol version number of the
* current message.
*
* \param type: a value (in the host byte order) which will be placed into the
* header.type field and that represents the type of the current message.
*
* \param value: a value (in the host byte order) which will be placed into
* the header.value field and that has a message-dependent meaning.
*
* \param length: a value (in the host by order) which will be placed into
* the header.length field, representing the payload length of the message.
*
* \return Nothing. The serialized header is returned into the 'header'
* variable.
*/
void
rpcap_createhdr(struct rpcap_header *header, uint8 ver, uint8 type, uint16 value, uint32 length)
{
memset(header, 0, sizeof(struct rpcap_header));
header->ver = ver;
header->type = type;
header->value = htons(value);
header->plen = htonl(length);
}
/*
* Convert a message type to a string containing the type name.
*/
static const char *requests[] =
{
NULL, /* not a valid message type */
"RPCAP_MSG_ERROR",
"RPCAP_MSG_FINDALLIF_REQ",
"RPCAP_MSG_OPEN_REQ",
"RPCAP_MSG_STARTCAP_REQ",
"RPCAP_MSG_UPDATEFILTER_REQ",
"RPCAP_MSG_CLOSE",
"RPCAP_MSG_PACKET",
"RPCAP_MSG_AUTH_REQ",
"RPCAP_MSG_STATS_REQ",
"RPCAP_MSG_ENDCAP_REQ",
"RPCAP_MSG_SETSAMPLING_REQ",
};
#define NUM_REQ_TYPES (sizeof requests / sizeof requests[0])
static const char *replies[] =
{
NULL,
NULL, /* this would be a reply to RPCAP_MSG_ERROR */
"RPCAP_MSG_FINDALLIF_REPLY",
"RPCAP_MSG_OPEN_REPLY",
"RPCAP_MSG_STARTCAP_REPLY",
"RPCAP_MSG_UPDATEFILTER_REPLY",
NULL, /* this would be a reply to RPCAP_MSG_CLOSE */
NULL, /* this would be a reply to RPCAP_MSG_PACKET */
"RPCAP_MSG_AUTH_REPLY",
"RPCAP_MSG_STATS_REPLY",
"RPCAP_MSG_ENDCAP_REPLY",
"RPCAP_MSG_SETSAMPLING_REPLY",
};
#define NUM_REPLY_TYPES (sizeof replies / sizeof replies[0])
const char *
rpcap_msg_type_string(uint8 type)
{
if (type & RPCAP_MSG_IS_REPLY) {
type &= ~RPCAP_MSG_IS_REPLY;
if (type >= NUM_REPLY_TYPES)
return NULL;
return replies[type];
} else {
if (type >= NUM_REQ_TYPES)
return NULL;
return requests[type];
}
}