ifiter_ioctl.c revision 15a44745412679c30a6d022733925af70a38b715
8462dfb880040cde3a60f047ec18808737fd7e85Mark Andrews/*
8462dfb880040cde3a60f047ec18808737fd7e85Mark Andrews * Copyright (C) 1999, 2000 Internet Software Consortium.
0c27b3fe77ac1d5094ba3521e8142d9e7973133fMark Andrews *
8462dfb880040cde3a60f047ec18808737fd7e85Mark Andrews * Permission to use, copy, modify, and distribute this software for any
0c27b3fe77ac1d5094ba3521e8142d9e7973133fMark Andrews * purpose with or without fee is hereby granted, provided that the above
0c27b3fe77ac1d5094ba3521e8142d9e7973133fMark Andrews * copyright notice and this permission notice appear in all copies.
0c27b3fe77ac1d5094ba3521e8142d9e7973133fMark Andrews *
8462dfb880040cde3a60f047ec18808737fd7e85Mark Andrews * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM
d58e33bfabfee19a035031dac633d36659738d56Evan Hunt * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
d58e33bfabfee19a035031dac633d36659738d56Evan Hunt * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
8462dfb880040cde3a60f047ec18808737fd7e85Mark Andrews * INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
92fe6db3e46016f4ce0d6e372c745469bba10b5eEvan Hunt * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
8462dfb880040cde3a60f047ec18808737fd7e85Mark Andrews * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
60988462e5d6db53205851d056e3482a29239be9Evan Hunt * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
* WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/* $Id: ifiter_ioctl.c,v 1.12 2000/07/27 09:52:44 tale Exp $ */
/*
* Obtain the list of network interfaces using the SIOCGLIFCONF ioctl.
* See netintro(4).
*/
#ifndef SIOCGLIFCONF
#define SIOCGLIFCONF SIOCGIFCONF
#define lifc_len ifc_len
#define lifc_buf ifc_buf
#define lifc_req ifc_req
#define lifconf ifconf
#else
#define ISC_HAVE_LIFC_FAMILY 1
#define ISC_HAVE_LIFC_FLAGS 1
#endif
#ifndef SIOCGLIFADDR
#define SIOCGLIFADDR SIOCGIFADDR
#define SIOCGLIFFLAGS SIOCGIFFLAGS
#define SIOCGLIFDSTADDR SIOCGIFDSTADDR
#define SIOCGLIFNETMASK SIOCGIFNETMASK
#define lifr_addr ifr_addr
#define lifr_name ifr_name
#define lifr_dstaddr ifr_dstaddr
#define lifr_flags ifr_flags
#define ss_family sa_family
#define lifreq ifreq
#endif
#define IFITER_MAGIC 0x49464954U /* IFIT. */
#define VALID_IFITER(t) ((t) != NULL && (t)->magic == IFITER_MAGIC)
struct isc_interfaceiter {
unsigned int magic; /* Magic number. */
isc_mem_t *mctx;
int socket;
struct lifconf ifc;
void *buf; /* Buffer for sysctl data. */
unsigned int bufsize; /* Bytes allocated. */
unsigned int pos; /* Current offset in
SIOCGLIFCONF data */
isc_interface_t current; /* Current interface data. */
isc_result_t result; /* Last result code. */
};
/*
* Size of buffer for SIOCGLIFCONF, in bytes. We assume no sane system
* will have more than a megabyte of interface configuration data.
*/
#define IFCONF_BUFSIZE_INITIAL 4096
#define IFCONF_BUFSIZE_MAX 1048576
isc_result_t
isc_interfaceiter_create(isc_mem_t *mctx, isc_interfaceiter_t **iterp) {
isc_interfaceiter_t *iter;
isc_result_t result;
REQUIRE(mctx != NULL);
REQUIRE(iterp != NULL);
REQUIRE(*iterp == NULL);
iter = isc_mem_get(mctx, sizeof(*iter));
if (iter == NULL)
return (ISC_R_NOMEMORY);
iter->mctx = mctx;
iter->buf = NULL;
/*
* Create an unbound datagram socket to do the SIOCGLIFADDR ioctl on.
*/
if ((iter->socket = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
UNEXPECTED_ERROR(__FILE__, __LINE__,
"making interface scan socket: %s",
strerror(errno));
result = ISC_R_UNEXPECTED;
goto socket_failure;
}
/*
* Get the interface configuration, allocating more memory if
* necessary.
*/
iter->bufsize = IFCONF_BUFSIZE_INITIAL;
for (;;) {
iter->buf = isc_mem_get(mctx, iter->bufsize);
if (iter->buf == NULL) {
result = ISC_R_NOMEMORY;
goto alloc_failure;
}
memset(&iter->ifc.lifc_len, 0, sizeof(iter->ifc.lifc_len));
#ifdef ISC_HAVE_LIFC_FAMILY
iter->ifc.lifc_family = AF_UNSPEC;
#endif
#ifdef ISC_HAVE_LIFC_FLAGS
iter->ifc.lifc_flags = 0;
#endif
iter->ifc.lifc_len = iter->bufsize;
iter->ifc.lifc_buf = iter->buf;
/*
* Ignore the HP/UX warning about "interger overflow during
* conversion. It comes from its own macro definition,
* and is really hard to shut up.
*/
if (ioctl(iter->socket, SIOCGLIFCONF, (char *)&iter->ifc)
== -1) {
if (errno != EINVAL) {
UNEXPECTED_ERROR(__FILE__, __LINE__,
"get interface configuration: %s",
strerror(errno));
result = ISC_R_UNEXPECTED;
goto ioctl_failure;
}
/*
* EINVAL. Retry with a bigger buffer.
*/
} else {
/*
* The ioctl succeeded.
* Some OS's just return what will fit rather
* than set EINVAL if the buffer is too small
* to fit all the interfaces in. If
* ifc.lifc_len is too near to the end of the
* buffer we will grow it just in case and
* retry.
*/
if (iter->ifc.lifc_len + 2 * sizeof(struct lifreq)
< iter->bufsize)
break;
}
if (iter->bufsize >= IFCONF_BUFSIZE_MAX) {
UNEXPECTED_ERROR(__FILE__, __LINE__,
"get interface configuration: "
"maximum buffer size exceeded");
result = ISC_R_UNEXPECTED;
goto ioctl_failure;
}
isc_mem_put(mctx, iter->buf, iter->bufsize);
iter->bufsize *= 2;
}
/*
* A newly created iterator has an undefined position
* until isc_interfaceiter_first() is called.
*/
iter->pos = (unsigned int) -1;
iter->result = ISC_R_FAILURE;
iter->magic = IFITER_MAGIC;
*iterp = iter;
return (ISC_R_SUCCESS);
ioctl_failure:
isc_mem_put(mctx, iter->buf, iter->bufsize);
alloc_failure:
(void) close(iter->socket);
socket_failure:
isc_mem_put(mctx, iter, sizeof *iter);
return (result);
}
/*
* Get information about the current interface to iter->current.
* If successful, return ISC_R_SUCCESS.
* If the interface has an unsupported address family, or if
* some operation on it fails, return ISC_R_IGNORE to make
* the higher-level iterator code ignore it.
*/
static isc_result_t
internal_current(isc_interfaceiter_t *iter) {
struct lifreq *ifrp;
struct lifreq lifreq;
int family;
REQUIRE(VALID_IFITER(iter));
REQUIRE (iter->pos < (unsigned int) iter->ifc.lifc_len);
ifrp = (struct lifreq *)((char *) iter->ifc.lifc_req + iter->pos);
memset(&lifreq, 0, sizeof lifreq);
memcpy(&lifreq, ifrp, sizeof lifreq);
family = lifreq.lifr_addr.ss_family;
if (family != AF_INET)
return (ISC_R_IGNORE);
memset(&iter->current, 0, sizeof(iter->current));
iter->current.af = family;
INSIST(sizeof(lifreq.lifr_name) <= sizeof(iter->current.name));
memcpy(iter->current.name, lifreq.lifr_name, sizeof(lifreq.lifr_name));
get_addr(family, &iter->current.address,
(struct sockaddr *)&lifreq.lifr_addr);
/*
* Get interface flags.
*/
iter->current.flags = 0;
/*
* Ignore the HP/UX warning about "interger overflow during
* conversion. It comes from its own macro definition,
* and is really hard to shut up.
*/
if (ioctl(iter->socket, SIOCGLIFFLAGS, (char *) &lifreq) < 0) {
UNEXPECTED_ERROR(__FILE__, __LINE__,
"%s: getting interface flags: %s",
lifreq.lifr_name,
strerror(errno));
return (ISC_R_IGNORE);
}
if ((lifreq.lifr_flags & IFF_UP) != 0)
iter->current.flags |= INTERFACE_F_UP;
if ((lifreq.lifr_flags & IFF_POINTOPOINT) != 0)
iter->current.flags |= INTERFACE_F_POINTTOPOINT;
if ((lifreq.lifr_flags & IFF_LOOPBACK) != 0)
iter->current.flags |= INTERFACE_F_LOOPBACK;
/*
* If the interface is point-to-point, get the destination address.
*/
if ((iter->current.flags & INTERFACE_F_POINTTOPOINT) != 0) {
/*
* Ignore the HP/UX warning about "interger overflow during
* conversion. It comes from its own macro definition,
* and is really hard to shut up.
*/
if (ioctl(iter->socket, SIOCGLIFDSTADDR, (char *)&lifreq)
< 0) {
UNEXPECTED_ERROR(__FILE__, __LINE__,
"%s: getting destination address: %s",
lifreq.lifr_name,
strerror(errno));
return (ISC_R_IGNORE);
}
get_addr(family, &iter->current.dstaddress,
(struct sockaddr *)&lifreq.lifr_dstaddr);
}
/*
* Get the network mask.
*/
memset(&lifreq, 0, sizeof lifreq);
memcpy(&lifreq, ifrp, sizeof lifreq);
switch (family) {
case AF_INET:
/*
* Ignore the HP/UX warning about "interger overflow during
* conversion. It comes from its own macro definition,
* and is really hard to shut up.
*/
if (ioctl(iter->socket, SIOCGLIFNETMASK, (char *)&lifreq)
< 0) {
UNEXPECTED_ERROR(__FILE__, __LINE__,
"%s: getting netmask: %s",
lifreq.lifr_name,
strerror(errno));
return (ISC_R_IGNORE);
}
get_addr(family, &iter->current.netmask,
(struct sockaddr *)&lifreq.lifr_addr);
break;
case AF_INET6: {
#ifdef lifr_addrlen
int i, bits;
/*
* Netmask already zeroed.
*/
iter->current.netmask.family = family;
for (i = 0 ; i < lifreq.lifr_addrlen; i += 8) {
bits = lifreq.lifr_addrlen - i;
bits = (bits < 8 ) ? (8-bits) : 0;
iter->current.netmask.type.in6.s6_addr[i/8] =
(~0 << bits) &0xff;
}
#endif
break;
}
}
return (ISC_R_SUCCESS);
}
/*
* Step the iterator to the next interface. Unlike
* isc_interfaceiter_next(), this may leave the iterator
* positioned on an interface that will ultimately
* be ignored. Return ISC_R_NOMORE if there are no more
* interfaces, otherwise ISC_R_SUCCESS.
*/
static isc_result_t
internal_next(isc_interfaceiter_t *iter) {
struct lifreq *ifrp;
REQUIRE (iter->pos < (unsigned int) iter->ifc.lifc_len);
ifrp = (struct lifreq *)((char *) iter->ifc.lifc_req + iter->pos);
#ifdef ISC_PLATFORM_HAVESALEN
if (ifrp->lifr_addr.sa_len > sizeof(struct sockaddr))
iter->pos += sizeof(ifrp->lifr_name) + ifrp->lifr_addr.sa_len;
else
#endif
iter->pos += sizeof *ifrp;
if (iter->pos >= (unsigned int) iter->ifc.lifc_len)
return (ISC_R_NOMORE);
return (ISC_R_SUCCESS);
}
static void
internal_destroy(isc_interfaceiter_t *iter) {
(void) close(iter->socket);
}