1 /*****************************************************************************
2 * netutils.c: various network functions
4 *****************************************************************************
6 *****************************************************************************/
8 /*****************************************************************************
10 *****************************************************************************/
11 #include <netdb.h> /* gethostbyname() */
12 #include <stdlib.h> /* free(), realloc(), atoi() */
13 #include <errno.h> /* errno() */
14 #include <string.h> /* bzero(), bcopy() */
15 #include <sys/ioctl.h> /* ioctl() */
16 #include <arpa/inet.h> /* htons(), htonl() */
19 #include <net/if.h> /* interface (arch-dependent) */
31 /*****************************************************************************
32 * BuildInetAddr: build an Internet address descriptor
33 *****************************************************************************
34 * Build an internet socket descriptor from a host name, or an ip, and a port.
35 * If the address is NULL, then INADDR_ANY will be used, allowing to receive
36 * on any address for a local socket. Usually, in this case, 'port' is also null
37 * and the function always succeeds.
38 *****************************************************************************/
39 int BuildInetAddr( struct sockaddr_in *p_sa_in, char *psz_in_addr, int i_port )
41 struct hostent *p_hostent; /* host descriptor */
43 bzero( p_sa_in, sizeof( struct sockaddr_in ) );
44 p_sa_in->sin_family = AF_INET; /* family */
45 p_sa_in->sin_port = htons( i_port ); /* port */
47 /* Use INADDR_ANY if psz_in_addr is NULL */
48 if( psz_in_addr == NULL )
50 p_sa_in->sin_addr.s_addr = htonl(INADDR_ANY);
52 /* Try to convert address directly from in_addr - this will work if
53 * psz_in_addr is dotted decimal. */
54 else if( !inet_aton( psz_in_addr, &p_sa_in->sin_addr) )
56 /* The convertion failed: the address is an host name, which needs
58 intf_DbgMsg("debug: resolving internet address %s...\n", psz_in_addr);
59 if ( (p_hostent = gethostbyname(psz_in_addr)) == NULL)
61 intf_ErrMsg("error: unknown host %s\n", psz_in_addr);
65 /* Copy the first address of the host in the socket address */
66 bcopy( p_hostent->h_addr_list[0], &p_sa_in->sin_addr, p_hostent->h_length);
72 /*****************************************************************************
73 * ServerPort: extract port from a "server:port" adress
74 *****************************************************************************
75 * Returns the port number in a "server:port" address and replace the ":" by
76 * a NUL character, or returns -1.
77 *****************************************************************************/
78 int ServerPort( char *psz_addr )
82 /* Scan string for ':' */
83 for( psz_index = psz_addr; *psz_index && (*psz_index != ':'); psz_index++ )
88 /* If a port number has been found, convert it and return it */
89 if( *psz_index == ':' )
92 return( atoi( psz_index + 1 ) );
99 /*****************************************************************************
100 * ReadIfConf: Read the configuration of an interface
101 *****************************************************************************
102 * i_sockfd must reference a socket open as follow: AF_INET, DOCK_DGRAM, 0
103 *****************************************************************************/
104 int ReadIfConf(int i_sockfd, if_descr_t* p_ifdescr, char* psz_name)
108 struct ifreq ifr_config;
113 /* Which interface are we interested in ? */
114 strcpy(ifr_config.ifr_name, psz_name);
116 /* Read the flags for that interface */
117 i_rc = ioctl(i_sockfd, SIOCGIFFLAGS, (byte_t *)&ifr_config);
120 p_ifdescr->i_flags = ifr_config.ifr_flags;
121 intf_DbgMsg("%s flags: 0x%x\n", psz_name, p_ifdescr->i_flags);
125 intf_ErrMsg("Cannot read flags for interface %s: %s\n", psz_name,
130 /* Read physical address of the interface and store it in our description */
131 i_rc = ioctl(i_sockfd, SIOCGIFHWADDR, (byte_t *)&ifr_config);
134 memcpy(&p_ifdescr->sa_phys_addr, &ifr_config.ifr_addr, sizeof(struct sockaddr));
135 intf_DbgMsg("%s MAC address: %2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x\n", psz_name,
136 p_ifdescr->sa_phys_addr.sa_data[0]&0xff,
137 p_ifdescr->sa_phys_addr.sa_data[1]&0xff,
138 p_ifdescr->sa_phys_addr.sa_data[2]&0xff,
139 p_ifdescr->sa_phys_addr.sa_data[3]&0xff,
140 p_ifdescr->sa_phys_addr.sa_data[4]&0xff,
141 p_ifdescr->sa_phys_addr.sa_data[5]&0xff);
145 intf_ErrMsg("Cannot read hardware address for interface %s: %s\n",
146 psz_name, strerror(errno));
150 /* Read IP address of the interface and store it in our description */
151 i_rc = ioctl(i_sockfd, SIOCGIFADDR, (byte_t *)&ifr_config);
154 memcpy(&p_ifdescr->sa_net_addr, &ifr_config.ifr_addr, sizeof(struct sockaddr));
155 intf_DbgMsg("%s IP address: %s\n", psz_name,
156 inet_ntoa(p_ifdescr->sa_net_addr.sin_addr));
160 intf_ErrMsg("Cannot read network address for interface %s: %s\n",
161 psz_name, strerror(errno));
165 /* Read broadcast address of the interface and store it in our description */
166 if(p_ifdescr->i_flags & IFF_POINTOPOINT)
168 intf_DbgMsg("%s doen't not support broadcast\n", psz_name);
169 i_rc = ioctl(i_sockfd, SIOCGIFDSTADDR, (byte_t *)&ifr_config);
173 intf_DbgMsg("%s supports broadcast\n", psz_name);
174 i_rc = ioctl(i_sockfd, SIOCGIFBRDADDR, (byte_t *)&ifr_config);
178 memcpy(&p_ifdescr->sa_bcast_addr, &ifr_config.ifr_addr, sizeof(struct sockaddr));
179 intf_DbgMsg("%s broadcast address: %s\n", psz_name,
180 inet_ntoa(p_ifdescr->sa_bcast_addr.sin_addr));
184 intf_ErrMsg("Cannot read broadcast address for interface %s: %s\n",
185 psz_name, strerror(errno));
188 #endif /* SYS_LINUX */
195 /*****************************************************************************
196 * ReadNetConf: Retrieve the network configuration of the host
197 *****************************************************************************
198 * Only IP interfaces are listed, and only if they are up
199 * i_sockfd must reference a socket open as follow: AF_INET, DOCK_DGRAM, 0
200 *****************************************************************************/
201 int ReadNetConf(int i_sockfd, net_descr_t* p_net_descr)
204 struct ifreq* a_ifr_ifconf = NULL;
205 struct ifreq* p_ifr_current_if;
206 struct ifconf ifc_netconf;
210 #endif /* SYS_LINUX */
216 /* Start by assuming we have few than 3 interfaces (i_if_number will
217 be incremented by 1 when entering the loop) */
220 /* Retrieve network configuration for that host */
224 a_ifr_ifconf = realloc(a_ifr_ifconf, i_if_number*sizeof(struct ifreq));
225 ifc_netconf.ifc_len = i_if_number*sizeof(struct ifreq);
226 ifc_netconf.ifc_req = a_ifr_ifconf;
228 i_rc = ioctl(i_sockfd, SIOCGIFCONF, (byte_t*)&ifc_netconf);
231 intf_ErrMsg("Cannot read network configuration: %s\n",
236 /* If we detected ifc_len interfaces, this may mean that others have
237 been missed because the a_ifr_ifconf was to little, so increase
238 it's size and retry */
239 while( ifc_netconf.ifc_len >= i_if_number*sizeof(struct ifreq) );
241 /* No see what we detected */
244 /* Init the given net_descr_t struct */
245 p_net_descr->i_if_number = 0;
246 p_net_descr->a_if = NULL;
248 /* Iterate through the entries of the a_ifr_ifconf table */
249 p_ifr_current_if = ifc_netconf.ifc_req;
250 for( i_remaining = ifc_netconf.ifc_len / sizeof (struct ifreq);
251 i_remaining-- > 0; p_ifr_current_if++ )
253 intf_DbgMsg("Found interface %s\n", p_ifr_current_if->ifr_name);
255 /* Don't use an interface devoted to an address family other than IP */
256 if(p_ifr_current_if->ifr_addr.sa_family != AF_INET)
259 /* Read the status of this interface */
260 if( ioctl(i_sockfd, SIOCGIFFLAGS, (byte_t *)p_ifr_current_if) < 0 )
262 intf_ErrMsg("Cannot access interface %s: %s\n",
263 p_ifr_current_if->ifr_name, strerror(errno));
269 /* Skip this interface if it is not up or if this is a loopback one */
270 if( !p_ifr_current_if->ifr_flags & IFF_UP ||
271 p_ifr_current_if->ifr_flags & IFF_LOOPBACK )
274 /* Add an entry to the net_descr struct to store the description of
276 p_net_descr->i_if_number++;
277 p_net_descr->a_if = realloc(p_net_descr->a_if,
278 p_net_descr->i_if_number*sizeof(if_descr_t));
279 /* FIXME: Read the info ?? */
280 i_rc = ReadIfConf(i_sockfd, &p_net_descr->a_if[p_net_descr->i_if_number-1],
281 p_ifr_current_if->ifr_name);
286 /* Don't need the a_ifr_ifconf anymore */
287 free( a_ifr_ifconf );
288 #endif /* SYS_LINUX */