lib/libncp/sap.c

   1 /*
   2  * Copyright (c) 1999, Boris Popov
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *    This product includes software developed by Boris Popov.
  16  * 4. Neither the name of the author nor the names of any co-contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  *
  32  * $FreeBSD: src/lib/libncp/sap.c,v 1.2 1999/10/29 12:59:59 bp Exp $
  33  * $DragonFly: src/lib/libncp/sap.c,v 1.2 2003/06/17 04:26:50 dillon Exp $
  34  *
  35  */
  36 #include <stdlib.h>
  37 #include <string.h>
  38 #include <sys/types.h>
  39 #include <sys/socket.h>
  40 #include <sys/time.h>
  41 #include <netipx/ipx.h>
  42 #include <errno.h>
  43 #include <unistd.h>
  44 #include "ipxsap.h"
  45
  46 /*
  47  * TODO: These should go to ipx headers
  48  */
  49 #define ipx_set_net(x,y) ((x).x_net.s_net[0] = (y).x_net.s_net[0]); \
  50                          ((x).x_net.s_net[1]=(y).x_net.s_net[1])
  51 #define ipx_set_nullnet(x) ((x).x_net.s_net[0]=0); ((x).x_net.s_net[1]=0)
  52 #define ipx_set_nullhost(x) ((x).x_host.s_host[0] = 0); \
  53         ((x).x_host.s_host[1] = 0); ((x).x_host.s_host[2] = 0)
  54 #define ipx_set_wildnet(x)      ((x).x_net.s_net[0] = 0xFFFF); \
  55                                 ((x).x_net.s_net[1]=0xFFFF)
  56 #define ipx_set_wildhost(x) ((x).x_host.s_host[0] = 0xFFFF); \
  57         ((x).x_host.s_host[1] = 0xFFFF); ((x).x_host.s_host[2] = 0xFFFF);
  58
  59
  60 static struct sap_packet* sap_packet_alloc(int entries);
  61 static int sap_size(int entries, u_short operation);
  62 int (*sap_sendto_func)(void*,int,struct sockaddr_ipx*,int sock)=NULL;
  63
  64 static int
  65 sap_sendto(void* buffer, int size, struct sockaddr_ipx* daddr, int sock)
  66 {
  67         if (sap_sendto_func)
  68                 return sap_sendto_func(buffer,size,daddr,sock);
  69         return sendto(sock, (char*)buffer, size, 0,
  70             (struct sockaddr*)daddr, sizeof(*daddr));
  71 }
  72
  73 static struct sap_packet*
  74 sap_packet_alloc(int entries)
  75 {
  76         if (entries > IPX_SAP_MAX_ENTRIES)
  77                 return NULL;
  78         return
  79             (struct sap_packet*)malloc(sap_size(entries, IPX_SAP_GENERAL_RESPONSE));
  80 }
  81
  82 static int
  83 sap_size(int entries, u_short operation)
  84 {
  85         if (entries <= 0)
  86                 return 0;
  87         switch (operation) {
  88             case IPX_SAP_GENERAL_QUERY:
  89                 return entries == 1 ? IPX_SAP_REQUEST_LEN : 0;
  90             case IPX_SAP_GENERAL_RESPONSE:
  91                 if (entries > IPX_SAP_MAX_ENTRIES)
  92                         return 0;
  93                 return sizeof(struct sap_packet) + (entries - 1) * sizeof(struct sap_entry);
  94             case IPX_SAP_NEAREST_QUERY:
  95                 return entries == 1 ? IPX_SAP_REQUEST_LEN : 0;
  96             case IPX_SAP_NEAREST_RESPONSE:
  97                 return entries == 1 ? sizeof(struct sap_packet) : 0;
  98             default:
  99                 return 0;
 100         }
 101 }
 102
 103 void
 104 sap_copyname(char *dest, const char *src)
 105 {
 106         bzero(dest, IPX_SAP_SERVER_NAME_LEN);
 107         strncpy(dest, src, IPX_SAP_SERVER_NAME_LEN - 1);
 108 }
 109
 110 int
 111 sap_rq_init(struct sap_rq* rq, int sock)
 112 {
 113         rq->buffer = sap_packet_alloc(IPX_SAP_MAX_ENTRIES);
 114         if (rq->buffer == NULL)
 115                 return 0;
 116         rq->entries = 0;
 117         rq->buffer->operation = htons(IPX_SAP_GENERAL_QUERY);
 118         rq->dest_addr.sipx_family = AF_IPX;
 119         rq->dest_addr.sipx_len = sizeof(struct sockaddr_ipx);
 120         rq->sock = sock;
 121         return 1;
 122 }
 123
 124 int
 125 sap_rq_flush(struct sap_rq* rq)
 126 {
 127         int result;
 128
 129         if (rq->entries == 0)
 130                 return 0;
 131         result = sap_sendto(rq->buffer,
 132                 sap_size(rq->entries, ntohs(rq->buffer->operation)),
 133                 &rq->dest_addr, rq->sock);
 134         rq->entries = 0;
 135         return result;
 136 }
 137
 138 void
 139 sap_rq_general_query(struct sap_rq* rq, u_short ser_type)
 140 {
 141         struct sap_entry* sep;
 142
 143         sap_rq_flush(rq);
 144         rq->buffer->operation = htons(IPX_SAP_GENERAL_QUERY);
 145         sep = rq->buffer->sap_entries + rq->entries++;
 146         sep->server_type = htons(ser_type);
 147 }
 148
 149 void
 150 sap_rq_gns_request(struct sap_rq* rq, u_short ser_type)
 151 {
 152         struct sap_entry* sep;
 153
 154         sap_rq_flush(rq);
 155         rq->buffer->operation = htons(IPX_SAP_NEAREST_QUERY);
 156         sep = rq->buffer->sap_entries + rq->entries++;
 157         sep->server_type = htons(ser_type);
 158 }
 159
 160 void
 161 sap_rq_general_response(struct sap_rq* rq,u_short type,char *name,struct sockaddr_ipx* addr, u_short hops,int down_allow)
 162 {
 163         struct sap_entry* sep;
 164
 165         if (hops >= IPX_SAP_SERVER_DOWN && !down_allow) return;
 166         if (rq->entries >= IPX_SAP_MAX_ENTRIES)
 167                 sap_rq_flush(rq);
 168         if (rq->buffer->operation != htons(IPX_SAP_GENERAL_RESPONSE)){
 169                 sap_rq_flush(rq);
 170                 rq->buffer->operation = htons(IPX_SAP_GENERAL_RESPONSE);
 171         }
 172         sep = rq->buffer->sap_entries + rq->entries;
 173         sep->server_type = htons(type);
 174         sap_copyname(sep->server_name, name);
 175         memcpy(&sep->ipx, &addr->sipx_addr, sizeof(struct ipx_addr));
 176         sep->hops = htons(hops);
 177         rq->entries++;
 178 }
 179
 180 void
 181 sap_rq_gns_response(struct sap_rq* rq,u_short type,char *name,struct sockaddr_ipx* addr,u_short hops)
 182 {
 183         struct sap_entry* sep;
 184
 185         if (hops >= IPX_SAP_SERVER_DOWN) return;
 186         sap_rq_flush(rq);
 187         rq->buffer->operation = htons(IPX_SAP_NEAREST_RESPONSE);
 188         sep = rq->buffer->sap_entries + rq->entries;
 189         sep->server_type = htons(type);
 190         sap_copyname(sep->server_name, name);
 191         memcpy(&sep->ipx, &addr->sipx_addr, sizeof(struct ipx_addr));
 192         sep->hops = htons(hops);
 193         rq->entries++;
 194 }
 195
 196 void
 197 sap_rq_set_destination(struct sap_rq* rq,struct ipx_addr *dest)
 198 {
 199         sap_rq_flush(rq);
 200         memcpy(&rq->dest_addr.sipx_addr,dest,sizeof(struct ipx_addr));
 201 }
 202
 203 int
 204 sap_getsock(int *rsock) {
 205         struct sockaddr_ipx sap_addr;
 206         int opt, sock, slen;
 207
 208         sock = socket(AF_IPX, SOCK_DGRAM, 0);
 209         if (sock < 0)
 210                 return (errno);
 211         slen = sizeof(sap_addr);
 212         bzero(&sap_addr, slen);
 213         sap_addr.sipx_family = AF_IPX;
 214         sap_addr.sipx_len = slen;
 215         if (bind(sock, (struct sockaddr*)&sap_addr, slen) == -1) {
 216                 close(sock);
 217                 return(errno);
 218         }
 219         opt = 1;
 220         if (setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &opt, sizeof(opt)) != 0){
 221                 close(sock);
 222                 return(errno);
 223         }
 224         *rsock = sock;
 225         return(0);
 226 }
 227
 228 static int
 229 sap_recv(int sock,void *buf,int len,int flags, int timeout){
 230         fd_set rd, wr, ex;
 231         struct timeval tv;
 232         int result;
 233
 234         FD_ZERO(&rd);
 235         FD_ZERO(&wr);
 236         FD_ZERO(&ex);
 237         FD_SET(sock, &rd);
 238
 239         tv.tv_sec = timeout;
 240         tv.tv_usec = 0;
 241
 242         if ((result = select(sock + 1, &rd, &wr, &ex, &tv)) == -1) {
 243                 return result;
 244         }
 245         if (FD_ISSET(sock, &rd)) {
 246                 result = recv(sock, buf, len, flags);
 247         } else {
 248                 errno = ETIMEDOUT;
 249                 result = -1;
 250         }
 251         return result;
 252 }
 253
 254 int
 255 sap_find_nearest(int server_type, struct sockaddr_ipx *daddr, char *server_name)
 256 {
 257         struct ipx_addr addr;
 258         char data[1024];
 259         int sock, error, packets, len;
 260         struct sap_packet *reply = (struct sap_packet*)&data;
 261         struct sap_rq sap_rq;
 262
 263         error = sap_getsock(&sock);
 264         if (error)
 265                 return error;
 266         bzero(&addr, sizeof(addr));
 267         /* BAD: we should enum all ifs (and nets ?) */
 268         if (ipx_iffind(NULL, &addr) != 0) {
 269                 return (EPROTONOSUPPORT);
 270         }
 271         ipx_set_wildhost(addr);
 272         addr.x_port = htons(IPXPORT_SAP);
 273
 274         if (!sap_rq_init(&sap_rq, sock)) {
 275                 close(sock);
 276                 return(ENOMEM);
 277         }
 278         sap_rq_set_destination(&sap_rq, &addr);
 279         sap_rq_gns_request(&sap_rq, server_type);
 280         sap_rq_flush(&sap_rq);
 281         packets = 5;
 282         do {
 283                 len = sap_recv(sock, data, sizeof(data), 0, 1);
 284                 if (len >= 66 &&
 285                     ntohs(reply->operation) == IPX_SAP_NEAREST_RESPONSE)
 286                         break;
 287                 if (len < 0)
 288                         packets--;
 289         } while (packets > 0);
 290
 291         if (packets == 0) {
 292                 close(sock);
 293                 return ENETDOWN;
 294         }
 295
 296         daddr->sipx_addr = reply->sap_entries[0].ipx;
 297         daddr->sipx_family = AF_IPX;
 298         daddr->sipx_len = sizeof(struct sockaddr_ipx);
 299         sap_copyname(server_name, reply->sap_entries[0].server_name);
 300         errno = 0;
 301         close(sock);
 302         return 0;
 303 }