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 #include <config.h> 35 36 #include <string.h> /* for strlen(), ... */ 37 #include <stdlib.h> /* for malloc(), free(), ... */ 38 #include <stdarg.h> /* for functions with variable number of arguments */ 39 #include <errno.h> /* for the errno variable */ 40 #include "sockutils.h" 41 #include "rpcap-protocol.h" 42 #include <pcap/pcap.h> 43 44 #include "portability.h" 45 46 /* 47 * This file contains functions used both by the rpcap client and the 48 * rpcap daemon. 49 */ 50 51 /* 52 * This function sends a RPCAP error to our peer. 53 * 54 * It has to be called when the main program detects an error. 55 * It will send to our peer the 'buffer' specified by the user. 56 * This function *does not* request a RPCAP CLOSE connection. A CLOSE 57 * command must be sent explicitly by the program, since we do not know 58 * whether the error can be recovered in some way or if it is a 59 * non-recoverable one. 60 * 61 * \param sock: the socket we are currently using. 62 * 63 * \param ssl: if compiled with openssl, the optional ssl handler to use with the above socket. 64 * 65 * \param ver: the protocol version we want to put in the reply. 66 * 67 * \param errcode: a integer which tells the other party the type of error 68 * we had. 69 * 70 * \param error: an user-allocated (and '0' terminated) buffer that contains 71 * the error description that has to be transmitted to our peer. The 72 * error message cannot be longer than PCAP_ERRBUF_SIZE. 73 * 74 * \param errbuf: a pointer to a user-allocated buffer (of size 75 * PCAP_ERRBUF_SIZE) that will contain the error message (in case there 76 * is one). It could be network problem. 77 * 78 * \return '0' if everything is fine, '-1' if some errors occurred. The 79 * error message is returned in the 'errbuf' variable. 80 */ 81 int 82 rpcap_senderror(PCAP_SOCKET sock, SSL *ssl, uint8 ver, unsigned short errcode, const char *error, char *errbuf) 83 { 84 char sendbuf[RPCAP_NETBUF_SIZE]; /* temporary buffer in which data to be sent is buffered */ 85 int sendbufidx = 0; /* index which keeps the number of bytes currently buffered */ 86 uint16 length; 87 88 length = (uint16)strlen(error); 89 90 if (length > PCAP_ERRBUF_SIZE) 91 length = PCAP_ERRBUF_SIZE; 92 93 rpcap_createhdr((struct rpcap_header *) sendbuf, ver, RPCAP_MSG_ERROR, errcode, length); 94 95 if (sock_bufferize(NULL, sizeof(struct rpcap_header), NULL, &sendbufidx, 96 RPCAP_NETBUF_SIZE, SOCKBUF_CHECKONLY, errbuf, PCAP_ERRBUF_SIZE)) 97 return -1; 98 99 if (sock_bufferize(error, length, sendbuf, &sendbufidx, 100 RPCAP_NETBUF_SIZE, SOCKBUF_BUFFERIZE, errbuf, PCAP_ERRBUF_SIZE)) 101 return -1; 102 103 if (sock_send(sock, ssl, sendbuf, sendbufidx, errbuf, PCAP_ERRBUF_SIZE) < 0) 104 return -1; 105 106 return 0; 107 } 108 109 /* 110 * This function fills in a structure of type rpcap_header. 111 * 112 * It is provided just because the creation of an rpcap header is a common 113 * task. It accepts all the values that appears into an rpcap_header, and 114 * it puts them in place using the proper hton() calls. 115 * 116 * \param header: a pointer to a user-allocated buffer which will contain 117 * the serialized header, ready to be sent on the network. 118 * 119 * \param ver: a value (in the host byte order) which will be placed into the 120 * header.ver field and that represents the protocol version number of the 121 * current message. 122 * 123 * \param type: a value (in the host byte order) which will be placed into the 124 * header.type field and that represents the type of the current message. 125 * 126 * \param value: a value (in the host byte order) which will be placed into 127 * the header.value field and that has a message-dependent meaning. 128 * 129 * \param length: a value (in the host by order) which will be placed into 130 * the header.length field, representing the payload length of the message. 131 * 132 * \return Nothing. The serialized header is returned into the 'header' 133 * variable. 134 */ 135 void 136 rpcap_createhdr(struct rpcap_header *header, uint8 ver, uint8 type, uint16 value, uint32 length) 137 { 138 memset(header, 0, sizeof(struct rpcap_header)); 139 140 header->ver = ver; 141 header->type = type; 142 header->value = htons(value); 143 header->plen = htonl(length); 144 } 145 146 /* 147 * Convert a message type to a string containing the type name. 148 */ 149 static const char *requests[] = 150 { 151 NULL, /* not a valid message type */ 152 "RPCAP_MSG_ERROR", 153 "RPCAP_MSG_FINDALLIF_REQ", 154 "RPCAP_MSG_OPEN_REQ", 155 "RPCAP_MSG_STARTCAP_REQ", 156 "RPCAP_MSG_UPDATEFILTER_REQ", 157 "RPCAP_MSG_CLOSE", 158 "RPCAP_MSG_PACKET", 159 "RPCAP_MSG_AUTH_REQ", 160 "RPCAP_MSG_STATS_REQ", 161 "RPCAP_MSG_ENDCAP_REQ", 162 "RPCAP_MSG_SETSAMPLING_REQ", 163 }; 164 #define NUM_REQ_TYPES (sizeof requests / sizeof requests[0]) 165 166 static const char *replies[] = 167 { 168 NULL, 169 NULL, /* this would be a reply to RPCAP_MSG_ERROR */ 170 "RPCAP_MSG_FINDALLIF_REPLY", 171 "RPCAP_MSG_OPEN_REPLY", 172 "RPCAP_MSG_STARTCAP_REPLY", 173 "RPCAP_MSG_UPDATEFILTER_REPLY", 174 NULL, /* this would be a reply to RPCAP_MSG_CLOSE */ 175 NULL, /* this would be a reply to RPCAP_MSG_PACKET */ 176 "RPCAP_MSG_AUTH_REPLY", 177 "RPCAP_MSG_STATS_REPLY", 178 "RPCAP_MSG_ENDCAP_REPLY", 179 "RPCAP_MSG_SETSAMPLING_REPLY", 180 }; 181 #define NUM_REPLY_TYPES (sizeof replies / sizeof replies[0]) 182 183 const char * 184 rpcap_msg_type_string(uint8 type) 185 { 186 if (type & RPCAP_MSG_IS_REPLY) { 187 type &= ~RPCAP_MSG_IS_REPLY; 188 if (type >= NUM_REPLY_TYPES) 189 return NULL; 190 return replies[type]; 191 } else { 192 if (type >= NUM_REQ_TYPES) 193 return NULL; 194 return requests[type]; 195 } 196 } 197