/* $NetBSD: wire.c,v 1.1.1.3 2015/01/17 16:34:18 christos Exp $ */
/*
* Copyright (c) 1997-2014 Erez Zadok
* Copyright (c) 1990 Jan-Simon Pendry
* Copyright (c) 1990 Imperial College of Science, Technology & Medicine
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Jan-Simon Pendry at Imperial College, London.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*
* File: am-utils/libamu/wire.c
*
*/
/*
* This function returns the subnet (address&netmask) for the primary network
* interface. If the resulting address has an entry in the hosts file, the
* corresponding name is returned, otherwise the address is returned in
* standard internet format.
* As a side-effect, a list of local IP/net address is recorded for use
* by the islocalnet() function.
*
* Derived from original by Paul Anderson (23/4/90)
* Updates from Dirk Grunwald (11/11/91)
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif /* HAVE_CONFIG_H */
#include <am_defs.h>
#include <amu.h>
#ifdef HAVE_IFADDRS_H
#include <ifaddrs.h>
#endif /* HAVE_IFADDRS_H */
#ifdef HAVE_IRS_H
# include <irs.h>
#endif /* HAVE_IRS_H */
/*
* List of locally connected networks
*/
typedef struct addrlist addrlist;
struct addrlist {
addrlist *ip_next;
u_long ip_addr; /* address of network */
u_long ip_mask;
char *ip_net_num; /* number of network */
char *ip_net_name; /* name of network */
};
static addrlist *localnets = NULL;
#if defined(IFF_LOCAL_LOOPBACK) && !defined(IFF_LOOPBACK)
# define IFF_LOOPBACK IFF_LOCAL_LOOPBACK
#endif /* defined(IFF_LOCAL_LOOPBACK) && !defined(IFF_LOOPBACK) */
#define C(x) ((x) & 0xff)
#define GFBUFLEN 1024
#define S2IN(s) (((struct sockaddr_in *)(s))->sin_addr.s_addr)
/* return malloc'ed buffer. caller must free it */
char *
print_wires(void)
{
addrlist *al;
char s[256];
int i;
char *buf;
int bufcount = 0;
int buf_size = 1024;
buf = SALLOC(buf_size); /* initial allocation (may grow!) */
if (!buf)
return NULL;
if (!localnets) {
xstrlcpy(buf, "No networks\n", buf_size);
return buf;
}
/* check if there's more than one network */
if (!localnets->ip_next) {
/* use buf_size for sizeof(buf) because of the realloc() below */
xsnprintf(buf, buf_size,
"Network: wire=\"%s\" (netnumber=%s).\n",
localnets->ip_net_name, localnets->ip_net_num);
return buf;
}
buf[0] = '\0'; /* null out buffer before appending */
for (i = 1, al = localnets; al; al = al->ip_next, i++) {
xsnprintf(s, sizeof(s), "Network %d: wire=\"%s\" (netnumber=%s).\n",
i, al->ip_net_name, al->ip_net_num);
bufcount += strlen(s);
if (bufcount > buf_size) {
buf_size *= 2;
buf = xrealloc(buf, buf_size);
}
xstrlcat(buf, s, buf_size);
}
return buf;
}
static struct addrlist *
getwire_lookup(u_long address, u_long netmask, int ishost)
{
struct addrlist *al;
u_long subnet;
char netNumberBuf[64];
char buf[GFBUFLEN], *s;
#ifdef HAVE_IRS_H
struct nwent *np;
#else /* not HAVE_IRS_H */
struct netent *np;
#endif /* not HAVE_IRS_H */
/*
* Add interface to local network singly linked list
*/
al = ALLOC(struct addrlist);
al->ip_addr = address;
al->ip_mask = netmask;
al->ip_net_name = NO_SUBNET; /* fill in a bit later */
al->ip_net_num = "0.0.0.0"; /* fill in a bit later */
al->ip_next = NULL;
subnet = ntohl(address) & ntohl(netmask);
if (ishost)
np = NULL;
else {
#ifdef HAVE_IRS_H
u_long mask = ntohl(netmask);
static struct irs_acc *irs_gen;
static struct irs_nw *irs_nw;
u_long net;
int maskbits;
u_char addr[4];
if (irs_gen == NULL)
#ifdef irs_irp_acc
/*
* bsdi4 added another argument to this function, without changing
* its name. The irs_irp_acc is the one (hacky) distinguishing
* feature found in <irs.h> that can differentiate between bsdi3 and
* bsdi4.
*/
irs_gen = irs_gen_acc("", NULL);
#else /* not irs_irp_acc */
irs_gen = irs_gen_acc("");
#endif /* not irs_irp_acc */
if (irs_gen && irs_nw == NULL)
irs_nw = (*irs_gen->nw_map)(irs_gen);
net = ntohl(address) & (mask = ntohl(netmask));
addr[0] = (0xFF000000 & net) >> 24;
addr[1] = (0x00FF0000 & net) >> 16;
addr[2] = (0x0000FF00 & net) >> 8;
addr[3] = (0x000000FF & net);
for (maskbits = 32; !(mask & 1); mask >>= 1)
maskbits--;
np = (*irs_nw->byaddr)(irs_nw, addr, maskbits, AF_INET);
#else /* not HAVE_IRS_H */
np = getnetbyaddr(subnet, AF_INET);
/*
* Some systems (IRIX 6.4) cannot getnetbyaddr on networks such as
* "128.59.16.0". Instead, they need to look for the short form of
* the network, "128.59.16". So if the first getnetbyaddr failed, we
* shift the subnet way from zeros and try again.
*/
if (!np) {
u_long short_subnet = subnet;
while (short_subnet && (short_subnet & 0x000000ff) == 0)
short_subnet >>= 8;
np = getnetbyaddr(short_subnet, AF_INET);
if (np)
plog(XLOG_WARNING, "getnetbyaddr failed on 0x%x, succeeded on 0x%x",
(u_int) subnet, (u_int) short_subnet);
}
#endif /* not HAVE_IRS_H */
}
if ((subnet & 0xffffff) == 0) {
xsnprintf(netNumberBuf, sizeof(netNumberBuf), "%lu", C(subnet >> 24));
} else if ((subnet & 0xffff) == 0) {
xsnprintf(netNumberBuf, sizeof(netNumberBuf), "%lu.%lu",
C(subnet >> 24), C(subnet >> 16));
} else if ((subnet & 0xff) == 0) {
xsnprintf(netNumberBuf, sizeof(netNumberBuf), "%lu.%lu.%lu",
C(subnet >> 24), C(subnet >> 16),
C(subnet >> 8));
} else {
xsnprintf(netNumberBuf, sizeof(netNumberBuf), "%lu.%lu.%lu.%lu",
C(subnet >> 24), C(subnet >> 16),
C(subnet >> 8), C(subnet));
}
/* fill in network number (string) */
al->ip_net_num = xstrdup(netNumberBuf);
if (np != NULL)
s = np->n_name;
else {
struct hostent *hp;
subnet = address & netmask;
hp = gethostbyaddr((char *) &subnet, 4, AF_INET);
if (hp != NULL)
s = (char *) hp->h_name;
else
s = inet_dquad(buf, sizeof(buf), subnet);
}
/* fill in network name (string) */
al->ip_net_name = xstrdup(s);
/* Let's be cautious here about buffer overflows -Ion */
if (strlen(s) > MAXHOSTNAMELEN) {
al->ip_net_name[MAXHOSTNAMELEN] = '\0';
plog(XLOG_WARNING, "Long hostname %s truncated to %d characters",
s, MAXHOSTNAMELEN);
}
return (al);
}
/*
* Make a dotted quad from a 32bit IP address
* addr is in network byte order.
* sizeof(buf) needs to be at least 16.
*/
char *
inet_dquad(char *buf, size_t l, u_long addr)
{
addr = ntohl(addr);
xsnprintf(buf, l, "%ld.%ld.%ld.%ld",
((addr >> 24) & 0xff),
((addr >> 16) & 0xff),
((addr >> 8) & 0xff),
((addr >> 0) & 0xff));
return buf;
}
/*
* Determine whether a network is on a local network
* (addr) is in network byte order.
*/
int
islocalnet(u_long addr)
{
addrlist *al;
for (al = localnets; al; al = al->ip_next)
if (((addr ^ al->ip_addr) & al->ip_mask) == 0)
return TRUE;
#ifdef DEBUG
{
char buf[16];
plog(XLOG_INFO, "%s is on a remote network",
inet_dquad(buf, sizeof(buf), addr));
}
#endif /* DEBUG */
return FALSE;
}
/*
* Determine whether a network name is one of the local networks
* of a host.
*/
int
is_network_member(const char *net)
{
addrlist *al;
/*
* If the network name string does not contain a '/', use old behavior.
* If it does contain a '/' then interpret the string as a network/netmask
* pair. If "netmask" doesn't exist, use the interface's own netmask.
* Also support fully explicit netmasks such as 255.255.255.0 as well as
* bit-length netmask such as /24 (hex formats such 0xffffff00 work too).
*/
if (strchr(net, '/') == NULL) {
for (al = localnets; al; al = al->ip_next)
if (STREQ(net, al->ip_net_name) || STREQ(net, al->ip_net_num))
return TRUE;
} else {
char *netstr = xstrdup(net), *maskstr;
u_long netnum, masknum = 0;
maskstr = strchr(netstr, '/');
if (maskstr == NULL) {
plog(XLOG_ERROR, "%s: netstr %s does not have a `/'", __func__, netstr);
XFREE(netstr);
return FALSE;
}
maskstr[0] = '\0'; /* null terminate netstr */
maskstr++;
if (*maskstr == '\0') /* if empty string, make it NULL */
maskstr = NULL;
/* check if netmask uses a dotted-quad or bit-length, or not defined at all */
if (maskstr) {
if (strchr(maskstr, '.')) {
/* XXX: inet_addr is obsolste, convert to inet_aton() */
masknum = inet_addr(maskstr);
if (masknum == INADDR_NONE) /* can be invalid (-1) or all-1s */
masknum = 0xffffffff;
} else if (NSTRCEQ(maskstr, "0x", 2)) {
masknum = strtoul(maskstr, NULL, 16);
} else {
int bits = atoi(maskstr);
if (bits < 0)
bits = 0;
if (bits > 32)
bits = 32;
masknum = 0xffffffff << (32-bits);
}
}
netnum = inet_addr(netstr); /* not checking return value, b/c -1 (0xffffffff) is valid */
XFREE(netstr); /* netstr not needed any longer */
/* now check against each local interface */
for (al = localnets; al; al = al->ip_next) {
if ((al->ip_addr & (maskstr ? masknum : al->ip_mask)) == netnum)
return TRUE;
}
}
return FALSE;
}
/*
* Determine whether a IP address (netnum) is one of the local interfaces,
* returns TRUE/FALSE.
* Does not include the loopback interface: caller needs to check that.
*/
int
is_interface_local(u_long netnum)
{
addrlist *al;
for (al = localnets; al; al = al->ip_next) {
if (al->ip_addr == netnum)
return TRUE;
}
return FALSE;
}
#ifdef HAVE_GETIFADDRS
void
getwire(char **name1, char **number1)
{
addrlist *al = NULL, *tail = NULL;
struct ifaddrs *ifaddrs, *ifap;
#ifndef HAVE_STRUCT_IFADDRS_IFA_NEXT
int count = 0, i;
#endif /* not HAVE_STRUCT_IFADDRS_IFA_NEXT */
ifaddrs = NULL;
#ifdef HAVE_STRUCT_IFADDRS_IFA_NEXT
if (getifaddrs(&ifaddrs) < 0)
goto out;
for (ifap = ifaddrs; ifap != NULL; ifap = ifap->ifa_next) {
#else /* not HAVE_STRUCT_IFADDRS_IFA_NEXT */
if (getifaddrs(&ifaddrs, &count) < 0)
goto out;
for (i = 0,ifap = ifaddrs; i < count; ifap++, i++) {
#endif /* HAVE_STRUCT_IFADDRS_IFA_NEXT */
if (!ifap || !ifap->ifa_addr || ifap->ifa_addr->sa_family != AF_INET)
continue;
/*
* If the interface is the loopback, or it's not running,
* then ignore it.
*/
if (S2IN(ifap->ifa_addr) == htonl(INADDR_LOOPBACK))
continue;
if ((ifap->ifa_flags & IFF_RUNNING) == 0)
continue;
if ((ifap->ifa_flags & IFF_POINTOPOINT) == 0)
al = getwire_lookup(S2IN(ifap->ifa_addr), S2IN(ifap->ifa_netmask), 0);
else
al = getwire_lookup(S2IN(ifap->ifa_dstaddr), 0xffffffff, 1);
/* append to the end of the list */
if (!localnets || tail == NULL) {
localnets = tail = al;
tail->ip_next = NULL;
} else {
tail->ip_next = al;
tail = al;
}
}
out:
if (ifaddrs)
XFREE(ifaddrs);
if (localnets) {
*name1 = localnets->ip_net_name;
*number1 = localnets->ip_net_num;
} else {
*name1 = NO_SUBNET;
*number1 = "0.0.0.0";
}
}
#else /* not HAVE_GETIFADDRS */
#if defined(HAVE_STRUCT_IFREQ_IFR_ADDR) && defined(HAVE_STRUCT_SOCKADDR_SA_LEN)
# define SIZE(ifr) (MAX((ifr)->ifr_addr.sa_len, sizeof((ifr)->ifr_addr)) + sizeof(ifr->ifr_name))
#else /* not defined(HAVE_STRUCT_IFREQ_IFR_ADDR) && defined(HAVE_STRUCT_SOCKADDR_SA_LEN) */
# define SIZE(ifr) sizeof(struct ifreq)
#endif /* not defined(HAVE_STRUCT_IFREQ_IFR_ADDR) && defined(HAVE_STRUCT_SOCKADDR_SA_LEN) */
#define clist (ifc.ifc_ifcu.ifcu_req)
#define count (ifc.ifc_len/sizeof(struct ifreq))
void
getwire(char **name1, char **number1)
{
struct ifconf ifc;
struct ifreq *ifr, ifrpool;
caddr_t cp, cplim;
int fd = -1;
u_long address;
addrlist *al = NULL, *tail = NULL;
char buf[GFBUFLEN];
#ifndef SIOCGIFFLAGS
/* if cannot get interface flags, return nothing */
plog(XLOG_ERROR, "getwire unable to get interface flags");
localnets = NULL;
return;
#endif /* not SIOCGIFFLAGS */
/*
* Get suitable socket
*/
if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
goto out;
/*
* Fill in ifconf details
*/
memset(&buf[0], 0, GFBUFLEN);
ifc.ifc_len = sizeof(buf);
ifc.ifc_buf = buf;
/*
* Get network interface configurations
*/
if (ioctl(fd, SIOCGIFCONF, (caddr_t) & ifc) < 0)
goto out;
/*
* Upper bound on array
*/
cplim = buf + ifc.ifc_len;
/*
* This is some magic to cope with both "traditional" and the
* new 4.4BSD-style struct sockaddrs. The new structure has
* variable length and a size field to support longer addresses.
* AF_LINK is a new definition for 4.4BSD.
*/
/*
* Scan the list looking for a suitable interface
*/
for (cp = buf; cp < cplim; /* increment in the loop body */) {
memcpy(&ifrpool, cp, sizeof(ifrpool));
ifr = &ifrpool;
cp += SIZE(ifr);
if (ifr->ifr_addr.sa_family != AF_INET)
continue;
address = ((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr.s_addr;
/*
* Get interface flags
*/
if (ioctl(fd, SIOCGIFFLAGS, (caddr_t) ifr) < 0)
continue;
/*
* If the interface is the loopback, or it's not running,
* then ignore it.
*/
if (address == htonl(INADDR_LOOPBACK))
continue;
/*
* Fix for 0.0.0.0 loopback on SunOS 3.X which defines IFF_ROUTE
* instead of IFF_LOOPBACK.
*/
#ifdef IFF_ROUTE
if (ifr->ifr_flags == (IFF_UP|IFF_RUNNING))
continue;
#endif /* IFF_ROUTE */
/* if the interface is not UP or not RUNNING, skip it */
if ((ifr->ifr_flags & IFF_RUNNING) == 0 ||
(ifr->ifr_flags & IFF_UP) == 0)
continue;
if ((ifr->ifr_flags & IFF_POINTOPOINT) == 0) {
/*
* Get the netmask of this interface
*/
if (ioctl(fd, SIOCGIFNETMASK, (caddr_t) ifr) < 0)
continue;
al = getwire_lookup(address, S2IN(&ifr->ifr_addr), 0);
} else
al = getwire_lookup(address, 0xffffffff, 1);
/* append to the end of the list */
if (!localnets) {
localnets = tail = al;
tail->ip_next = NULL;
} else {
tail->ip_next = al;
tail = al;
}
}
out:
if (fd >= 0)
close(fd);
if (localnets) {
*name1 = localnets->ip_net_name;
*number1 = localnets->ip_net_num;
} else {
*name1 = NO_SUBNET;
*number1 = "0.0.0.0";
}
}
#endif /* not HAVE_GETIFADDRS */