1 /*****************************************************************************
2 * netutils.c: various network functions
3 *****************************************************************************
4 * Copyright (C) 1999, 2000 VideoLAN
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
18 * You should have received a copy of the GNU General Public
19 * License along with this program; if not, write to the
20 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
21 * Boston, MA 02111-1307, USA.
22 *****************************************************************************/
24 /*****************************************************************************
26 *****************************************************************************/
27 #include <netdb.h> /* gethostbyname() */
28 #include <stdlib.h> /* free(), realloc(), atoi() */
29 #include <errno.h> /* errno() */
30 #include <string.h> /* bzero(), bcopy() */
33 #include <netinet/in.h> /* struct in_addr */
34 #include <sys/socket.h> /* struct sockaddr */
37 #include <arpa/inet.h> /* htons(), htonl() */
40 #include <sys/ioctl.h> /* ioctl() */
41 #include <net/if.h> /* interface (arch-dependent) */
53 /*****************************************************************************
54 * BuildInetAddr: build an Internet address descriptor
55 *****************************************************************************
56 * Build an internet socket descriptor from a host name, or an ip, and a port.
57 * If the address is NULL, then INADDR_ANY will be used, allowing to receive
58 * on any address for a local socket. Usually, in this case, 'port' is also null
59 * and the function always succeeds.
60 *****************************************************************************/
61 int BuildInetAddr( struct sockaddr_in *p_sa_in, char *psz_in_addr, int i_port )
63 struct hostent *p_hostent; /* host descriptor */
65 bzero( p_sa_in, sizeof( struct sockaddr_in ) );
66 p_sa_in->sin_family = AF_INET; /* family */
67 p_sa_in->sin_port = htons( i_port ); /* port */
69 /* Use INADDR_ANY if psz_in_addr is NULL */
70 if( psz_in_addr == NULL )
72 p_sa_in->sin_addr.s_addr = htonl(INADDR_ANY);
74 /* Try to convert address directly from in_addr - this will work if
75 * psz_in_addr is dotted decimal. */
76 else if( !inet_aton( psz_in_addr, &p_sa_in->sin_addr) )
78 /* The convertion failed: the address is an host name, which needs
80 intf_DbgMsg("debug: resolving internet address %s...\n", psz_in_addr);
81 if ( (p_hostent = gethostbyname(psz_in_addr)) == NULL)
83 intf_ErrMsg("error: unknown host %s\n", psz_in_addr);
87 /* Copy the first address of the host in the socket address */
88 bcopy( p_hostent->h_addr_list[0], &p_sa_in->sin_addr, p_hostent->h_length);
94 /*****************************************************************************
95 * ServerPort: extract port from a "server:port" adress
96 *****************************************************************************
97 * Returns the port number in a "server:port" address and replace the ":" by
98 * a NUL character, or returns -1.
99 *****************************************************************************/
100 int ServerPort( char *psz_addr )
104 /* Scan string for ':' */
105 for( psz_index = psz_addr; *psz_index && (*psz_index != ':'); psz_index++ )
110 /* If a port number has been found, convert it and return it */
111 if( *psz_index == ':' )
114 return( atoi( psz_index + 1 ) );
121 /*****************************************************************************
122 * ReadIfConf: Read the configuration of an interface
123 *****************************************************************************
124 * i_sockfd must reference a socket open as follow: AF_INET, DOCK_DGRAM, 0
125 *****************************************************************************/
126 int ReadIfConf(int i_sockfd, if_descr_t* p_ifdescr, char* psz_name)
130 struct ifreq ifr_config;
135 /* Which interface are we interested in ? */
136 strcpy(ifr_config.ifr_name, psz_name);
138 /* Read the flags for that interface */
139 i_rc = ioctl(i_sockfd, SIOCGIFFLAGS, (byte_t *)&ifr_config);
142 p_ifdescr->i_flags = ifr_config.ifr_flags;
143 intf_DbgMsg("%s flags: 0x%x\n", psz_name, p_ifdescr->i_flags);
147 intf_ErrMsg("Cannot read flags for interface %s: %s\n", psz_name,
152 /* Read physical address of the interface and store it in our description */
153 i_rc = ioctl(i_sockfd, SIOCGIFHWADDR, (byte_t *)&ifr_config);
156 memcpy(&p_ifdescr->sa_phys_addr, &ifr_config.ifr_addr, sizeof(struct sockaddr));
157 intf_DbgMsg("%s MAC address: %2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x\n", psz_name,
158 p_ifdescr->sa_phys_addr.sa_data[0]&0xff,
159 p_ifdescr->sa_phys_addr.sa_data[1]&0xff,
160 p_ifdescr->sa_phys_addr.sa_data[2]&0xff,
161 p_ifdescr->sa_phys_addr.sa_data[3]&0xff,
162 p_ifdescr->sa_phys_addr.sa_data[4]&0xff,
163 p_ifdescr->sa_phys_addr.sa_data[5]&0xff);
167 intf_ErrMsg("Cannot read hardware address for interface %s: %s\n",
168 psz_name, strerror(errno));
172 /* Read IP address of the interface and store it in our description */
173 i_rc = ioctl(i_sockfd, SIOCGIFADDR, (byte_t *)&ifr_config);
176 memcpy(&p_ifdescr->sa_net_addr, &ifr_config.ifr_addr, sizeof(struct sockaddr));
177 intf_DbgMsg("%s IP address: %s\n", psz_name,
178 inet_ntoa(p_ifdescr->sa_net_addr.sin_addr));
182 intf_ErrMsg("Cannot read network address for interface %s: %s\n",
183 psz_name, strerror(errno));
187 /* Read broadcast address of the interface and store it in our description */
188 if(p_ifdescr->i_flags & IFF_POINTOPOINT)
190 intf_DbgMsg("%s doen't not support broadcast\n", psz_name);
191 i_rc = ioctl(i_sockfd, SIOCGIFDSTADDR, (byte_t *)&ifr_config);
195 intf_DbgMsg("%s supports broadcast\n", psz_name);
196 i_rc = ioctl(i_sockfd, SIOCGIFBRDADDR, (byte_t *)&ifr_config);
200 memcpy(&p_ifdescr->sa_bcast_addr, &ifr_config.ifr_addr, sizeof(struct sockaddr));
201 intf_DbgMsg("%s broadcast address: %s\n", psz_name,
202 inet_ntoa(p_ifdescr->sa_bcast_addr.sin_addr));
206 intf_ErrMsg("Cannot read broadcast address for interface %s: %s\n",
207 psz_name, strerror(errno));
210 #endif /* SYS_LINUX */
217 /*****************************************************************************
218 * ReadNetConf: Retrieve the network configuration of the host
219 *****************************************************************************
220 * Only IP interfaces are listed, and only if they are up
221 * i_sockfd must reference a socket open as follow: AF_INET, DOCK_DGRAM, 0
222 *****************************************************************************/
223 int ReadNetConf(int i_sockfd, net_descr_t* p_net_descr)
226 struct ifreq* a_ifr_ifconf = NULL;
227 struct ifreq* p_ifr_current_if;
228 struct ifconf ifc_netconf;
232 #endif /* SYS_LINUX */
238 /* Start by assuming we have few than 3 interfaces (i_if_number will
239 be incremented by 1 when entering the loop) */
242 /* Retrieve network configuration for that host */
246 a_ifr_ifconf = realloc(a_ifr_ifconf, i_if_number*sizeof(struct ifreq));
247 ifc_netconf.ifc_len = i_if_number*sizeof(struct ifreq);
248 ifc_netconf.ifc_req = a_ifr_ifconf;
250 i_rc = ioctl(i_sockfd, SIOCGIFCONF, (byte_t*)&ifc_netconf);
253 intf_ErrMsg("Cannot read network configuration: %s\n",
258 /* If we detected ifc_len interfaces, this may mean that others have
259 been missed because the a_ifr_ifconf was to little, so increase
260 it's size and retry */
261 while( ifc_netconf.ifc_len >= i_if_number*sizeof(struct ifreq) );
263 /* No see what we detected */
266 /* Init the given net_descr_t struct */
267 p_net_descr->i_if_number = 0;
268 p_net_descr->a_if = NULL;
270 /* Iterate through the entries of the a_ifr_ifconf table */
271 p_ifr_current_if = ifc_netconf.ifc_req;
272 for( i_remaining = ifc_netconf.ifc_len / sizeof (struct ifreq);
273 i_remaining-- > 0; p_ifr_current_if++ )
275 intf_DbgMsg("Found interface %s\n", p_ifr_current_if->ifr_name);
277 /* Don't use an interface devoted to an address family other than IP */
278 if(p_ifr_current_if->ifr_addr.sa_family != AF_INET)
281 /* Read the status of this interface */
282 if( ioctl(i_sockfd, SIOCGIFFLAGS, (byte_t *)p_ifr_current_if) < 0 )
284 intf_ErrMsg("Cannot access interface %s: %s\n",
285 p_ifr_current_if->ifr_name, strerror(errno));
291 /* Skip this interface if it is not up or if this is a loopback one */
292 if( !p_ifr_current_if->ifr_flags & IFF_UP ||
293 p_ifr_current_if->ifr_flags & IFF_LOOPBACK )
296 /* Add an entry to the net_descr struct to store the description of
298 p_net_descr->i_if_number++;
299 p_net_descr->a_if = realloc(p_net_descr->a_if,
300 p_net_descr->i_if_number*sizeof(if_descr_t));
301 /* FIXME: Read the info ?? */
302 i_rc = ReadIfConf(i_sockfd, &p_net_descr->a_if[p_net_descr->i_if_number-1],
303 p_ifr_current_if->ifr_name);
308 /* Don't need the a_ifr_ifconf anymore */
309 free( a_ifr_ifconf );
310 #endif /* SYS_LINUX */