1 /* 2 * Copyright (c) 2002 - 2005 NetGroup, Politecnico di Torino (Italy) 3 * Copyright (c) 2005 - 2008 CACE Technologies, Davis (California) 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the Politecnico di Torino, CACE Technologies 16 * nor the names of its contributors may be used to endorse or promote 17 * products derived from this software without specific prior written 18 * permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 23 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 24 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 25 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 26 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 30 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 * 32 */ 33 34 #ifdef HAVE_CONFIG_H 35 #include <config.h> 36 #endif 37 38 #include <string.h> /* for strlen(), ... */ 39 #include <stdlib.h> /* for malloc(), free(), ... */ 40 #include <stdarg.h> /* for functions with variable number of arguments */ 41 #include <errno.h> /* for the errno variable */ 42 #include "sockutils.h" 43 #include "portability.h" 44 #include "rpcap-protocol.h" 45 #include <pcap/pcap.h> 46 47 /* 48 * This file contains functions used both by the rpcap client and the 49 * rpcap daemon. 50 */ 51 52 /* 53 * This function sends a RPCAP error to our peer. 54 * 55 * It has to be called when the main program detects an error. 56 * It will send to our peer the 'buffer' specified by the user. 57 * This function *does not* request a RPCAP CLOSE connection. A CLOSE 58 * command must be sent explicitly by the program, since we do not know 59 * whether the error can be recovered in some way or if it is a 60 * non-recoverable one. 61 * 62 * \param sock: the socket we are currently using. 63 * 64 * \param ver: the protocol version we want to put in the reply. 65 * 66 * \param errcode: a integer which tells the other party the type of error 67 * we had. 68 * 69 * \param error: an user-allocated (and '0' terminated) buffer that contains 70 * the error description that has to be transmitted to our peer. The 71 * error message cannot be longer than PCAP_ERRBUF_SIZE. 72 * 73 * \param errbuf: a pointer to a user-allocated buffer (of size 74 * PCAP_ERRBUF_SIZE) that will contain the error message (in case there 75 * is one). It could be network problem. 76 * 77 * \return '0' if everything is fine, '-1' if some errors occurred. The 78 * error message is returned in the 'errbuf' variable. 79 */ 80 int 81 rpcap_senderror(SOCKET sock, uint8 ver, unsigned short errcode, const char *error, char *errbuf) 82 { 83 char sendbuf[RPCAP_NETBUF_SIZE]; /* temporary buffer in which data to be sent is buffered */ 84 int sendbufidx = 0; /* index which keeps the number of bytes currently buffered */ 85 uint16 length; 86 87 length = (uint16)strlen(error); 88 89 if (length > PCAP_ERRBUF_SIZE) 90 length = PCAP_ERRBUF_SIZE; 91 92 rpcap_createhdr((struct rpcap_header *) sendbuf, ver, RPCAP_MSG_ERROR, errcode, length); 93 94 if (sock_bufferize(NULL, sizeof(struct rpcap_header), NULL, &sendbufidx, 95 RPCAP_NETBUF_SIZE, SOCKBUF_CHECKONLY, errbuf, PCAP_ERRBUF_SIZE)) 96 return -1; 97 98 if (sock_bufferize(error, length, sendbuf, &sendbufidx, 99 RPCAP_NETBUF_SIZE, SOCKBUF_BUFFERIZE, errbuf, PCAP_ERRBUF_SIZE)) 100 return -1; 101 102 if (sock_send(sock, sendbuf, sendbufidx, errbuf, PCAP_ERRBUF_SIZE) < 0) 103 return -1; 104 105 return 0; 106 } 107 108 /* 109 * This function fills in a structure of type rpcap_header. 110 * 111 * It is provided just because the creation of an rpcap header is a common 112 * task. It accepts all the values that appears into an rpcap_header, and 113 * it puts them in place using the proper hton() calls. 114 * 115 * \param header: a pointer to a user-allocated buffer which will contain 116 * the serialized header, ready to be sent on the network. 117 * 118 * \param ver: a value (in the host byte order) which will be placed into the 119 * header.ver field and that represents the protocol version number of the 120 * current message. 121 * 122 * \param type: a value (in the host byte order) which will be placed into the 123 * header.type field and that represents the type of the current message. 124 * 125 * \param value: a value (in the host byte order) which will be placed into 126 * the header.value field and that has a message-dependent meaning. 127 * 128 * \param length: a value (in the host by order) which will be placed into 129 * the header.length field, representing the payload length of the message. 130 * 131 * \return Nothing. The serialized header is returned into the 'header' 132 * variable. 133 */ 134 void 135 rpcap_createhdr(struct rpcap_header *header, uint8 ver, uint8 type, uint16 value, uint32 length) 136 { 137 memset(header, 0, sizeof(struct rpcap_header)); 138 139 header->ver = ver; 140 header->type = type; 141 header->value = htons(value); 142 header->plen = htonl(length); 143 } 144 145 /* 146 * Convert a message type to a string containing the type name. 147 */ 148 static const char *requests[] = 149 { 150 NULL, /* not a valid message type */ 151 "RPCAP_MSG_ERROR", 152 "RPCAP_MSG_FINDALLIF_REQ", 153 "RPCAP_MSG_OPEN_REQ", 154 "RPCAP_MSG_STARTCAP_REQ", 155 "RPCAP_MSG_UPDATEFILTER_REQ", 156 "RPCAP_MSG_CLOSE", 157 "RPCAP_MSG_PACKET", 158 "RPCAP_MSG_AUTH_REQ", 159 "RPCAP_MSG_STATS_REQ", 160 "RPCAP_MSG_ENDCAP_REQ", 161 "RPCAP_MSG_SETSAMPLING_REQ", 162 }; 163 #define NUM_REQ_TYPES (sizeof requests / sizeof requests[0]) 164 165 static const char *replies[] = 166 { 167 NULL, 168 NULL, /* this would be a reply to RPCAP_MSG_ERROR */ 169 "RPCAP_MSG_FINDALLIF_REPLY", 170 "RPCAP_MSG_OPEN_REPLY", 171 "RPCAP_MSG_STARTCAP_REPLY", 172 "RPCAP_MSG_UPDATEFILTER_REPLY", 173 NULL, /* this would be a reply to RPCAP_MSG_CLOSE */ 174 NULL, /* this would be a reply to RPCAP_MSG_PACKET */ 175 "RPCAP_MSG_AUTH_REPLY", 176 "RPCAP_MSG_STATS_REPLY", 177 "RPCAP_MSG_ENDCAP_REPLY", 178 "RPCAP_MSG_SETSAMPLING_REPLY", 179 }; 180 #define NUM_REPLY_TYPES (sizeof replies / sizeof replies[0]) 181 182 const char * 183 rpcap_msg_type_string(uint8 type) 184 { 185 if (type & RPCAP_MSG_IS_REPLY) { 186 type &= ~RPCAP_MSG_IS_REPLY; 187 if (type >= NUM_REPLY_TYPES) 188 return NULL; 189 return replies[type]; 190 } else { 191 if (type >= NUM_REQ_TYPES) 192 return NULL; 193 return requests[type]; 194 } 195 } 196