885 lines
25 KiB
C
885 lines
25 KiB
C
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/* -*- Mode: c; tab-width: 8; indent-tabs-mode: 1; c-basic-offset: 8; -*- */
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/*
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* Copyright (c) 1994, 1995, 1996, 1997, 1998
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* The Regents of the University of California. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the Computer Systems
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* Engineering Group at Lawrence Berkeley Laboratory.
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* 4. Neither the name of the University nor of the Laboratory may be used
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* to endorse or promote products derived from this software without
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* specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#ifdef HAVE_CONFIG_H
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#include "config.h"
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#endif
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#ifdef _WIN32
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#include <pcap-stdinc.h>
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#else /* _WIN32 */
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#include <sys/param.h>
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#ifndef MSDOS
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#include <sys/file.h>
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#endif
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#include <sys/ioctl.h>
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#include <sys/socket.h>
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#ifdef HAVE_SYS_SOCKIO_H
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#include <sys/sockio.h>
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#endif
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struct mbuf; /* Squelch compiler warnings on some platforms for */
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struct rtentry; /* declarations in <net/if.h> */
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#include <net/if.h>
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#include <netinet/in.h>
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#endif /* _WIN32 */
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#include <ctype.h>
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#include <errno.h>
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#include <memory.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#if !defined(_WIN32) && !defined(__BORLANDC__)
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#include <unistd.h>
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#endif /* !_WIN32 && !__BORLANDC__ */
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#ifdef HAVE_LIMITS_H
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#include <limits.h>
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#else
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#define INT_MAX 2147483647
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#endif
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#include "pcap-int.h"
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#ifdef HAVE_OS_PROTO_H
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#include "os-proto.h"
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#endif
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#ifndef _WIN32
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/* Not all systems have IFF_LOOPBACK */
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#ifdef IFF_LOOPBACK
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#define ISLOOPBACK(name, flags) ((flags) & IFF_LOOPBACK)
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#else
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#define ISLOOPBACK(name, flags) ((name)[0] == 'l' && (name)[1] == 'o' && \
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(isdigit((unsigned char)((name)[2])) || (name)[2] == '\0'))
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#endif
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#ifdef IFF_UP
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#define ISUP(flags) ((flags) & IFF_UP)
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#else
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#define ISUP(flags) 0
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#endif
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#ifdef IFF_RUNNING
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#define ISRUNNING(flags) ((flags) & IFF_RUNNING)
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#else
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#define ISRUNNING(flags) 0
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#endif
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/*
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* Map UN*X-style interface flags to libpcap flags.
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*/
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bpf_u_int32
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if_flags_to_pcap_flags(const char *name _U_, u_int if_flags)
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{
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bpf_u_int32 pcap_flags;
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pcap_flags = 0;
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if (ISLOOPBACK(name, if_flags))
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pcap_flags |= PCAP_IF_LOOPBACK;
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if (ISUP(if_flags))
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pcap_flags |= PCAP_IF_UP;
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if (ISRUNNING(if_flags))
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pcap_flags |= PCAP_IF_RUNNING;
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return (pcap_flags);
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}
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#endif
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static struct sockaddr *
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dup_sockaddr(struct sockaddr *sa, size_t sa_length)
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{
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struct sockaddr *newsa;
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if ((newsa = malloc(sa_length)) == NULL)
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return (NULL);
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return (memcpy(newsa, sa, sa_length));
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}
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/*
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* Construct a "figure of merit" for an interface, for use when sorting
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* the list of interfaces, in which interfaces that are up are superior
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* to interfaces that aren't up, interfaces that are up and running are
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* superior to interfaces that are up but not running, and non-loopback
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* interfaces that are up and running are superior to loopback interfaces,
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* and interfaces with the same flags have a figure of merit that's higher
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* the lower the instance number.
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*
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* The goal is to try to put the interfaces most likely to be useful for
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* capture at the beginning of the list.
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*
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* The figure of merit, which is lower the "better" the interface is,
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* has the uppermost bit set if the interface isn't running, the bit
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* below that set if the interface isn't up, the bit below that set
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* if the interface is a loopback interface, and the interface index
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* in the 29 bits below that. (Yes, we assume u_int is 32 bits.)
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*/
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static u_int
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get_figure_of_merit(pcap_if_t *dev)
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{
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const char *cp;
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u_int n;
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if (strcmp(dev->name, "any") == 0) {
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/*
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* Give the "any" device an artificially high instance
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* number, so it shows up after all other non-loopback
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* interfaces.
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*/
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n = 0x1FFFFFFF; /* 29 all-1 bits */
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} else {
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/*
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* A number at the end of the device name string is
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* assumed to be a unit number.
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*/
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cp = dev->name + strlen(dev->name) - 1;
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while (cp-1 >= dev->name && *(cp-1) >= '0' && *(cp-1) <= '9')
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cp--;
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if (*cp >= '0' && *cp <= '9')
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n = atoi(cp);
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else
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n = 0;
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}
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if (!(dev->flags & PCAP_IF_RUNNING))
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n |= 0x80000000;
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if (!(dev->flags & PCAP_IF_UP))
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n |= 0x40000000;
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if (dev->flags & PCAP_IF_LOOPBACK)
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n |= 0x20000000;
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return (n);
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}
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/*
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* Try to get a description for a given device.
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* Returns a mallocated description if it could and NULL if it couldn't.
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*
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* XXX - on FreeBSDs that support it, should it get the sysctl named
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* "dev.{adapter family name}.{adapter unit}.%desc" to get a description
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* of the adapter? Note that "dev.an.0.%desc" is "Aironet PC4500/PC4800"
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* with my Cisco 350 card, so the name isn't entirely descriptive. The
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* "dev.an.0.%pnpinfo" has a better description, although one might argue
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* that the problem is really a driver bug - if it can find out that it's
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* a Cisco 340 or 350, rather than an old Aironet card, it should use
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* that in the description.
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*
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* Do NetBSD, DragonflyBSD, or OpenBSD support this as well? FreeBSD
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* and OpenBSD let you get a description, but it's not generated by the OS,
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* it's set with another ioctl that ifconfig supports; we use that to get
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* a description in FreeBSD and OpenBSD, but if there is no such
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* description available, it still might be nice to get some description
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* string based on the device type or something such as that.
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*
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* In OS X, the System Configuration framework can apparently return
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* names in 10.4 and later.
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*
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* It also appears that freedesktop.org's HAL offers an "info.product"
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* string, but the HAL specification says it "should not be used in any
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* UI" and "subsystem/capability specific properties" should be used
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* instead and, in any case, I think HAL is being deprecated in
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* favor of other stuff such as DeviceKit. DeviceKit doesn't appear
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* to have any obvious product information for devices, but maybe
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* I haven't looked hard enough.
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*
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* Using the System Configuration framework, or HAL, or DeviceKit, or
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* whatever, would require that libpcap applications be linked with
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* the frameworks/libraries in question. That shouldn't be a problem
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* for programs linking with the shared version of libpcap (unless
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* you're running on AIX - which I think is the only UN*X that doesn't
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* support linking a shared library with other libraries on which it
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* depends, and having an executable linked only with the first shared
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* library automatically pick up the other libraries when started -
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* and using HAL or whatever). Programs linked with the static
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* version of libpcap would have to use pcap-config with the --static
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* flag in order to get the right linker flags in order to pick up
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* the additional libraries/frameworks; those programs need that anyway
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* for libpcap 1.1 and beyond on Linux, as, by default, it requires
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* -lnl.
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*
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* Do any other UN*Xes, or desktop environments support getting a
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* description?
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*/
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static char *
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get_if_description(const char *name)
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{
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#ifdef SIOCGIFDESCR
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char *description = NULL;
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int s;
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struct ifreq ifrdesc;
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#ifndef IFDESCRSIZE
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size_t descrlen = 64;
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#else
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size_t descrlen = IFDESCRSIZE;
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#endif /* IFDESCRSIZE */
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/*
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* Get the description for the interface.
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*/
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memset(&ifrdesc, 0, sizeof ifrdesc);
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strlcpy(ifrdesc.ifr_name, name, sizeof ifrdesc.ifr_name);
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s = socket(AF_INET, SOCK_DGRAM, 0);
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if (s >= 0) {
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#ifdef __FreeBSD__
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/*
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* On FreeBSD, if the buffer isn't big enough for the
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* description, the ioctl succeeds, but the description
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* isn't copied, ifr_buffer.length is set to the description
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* length, and ifr_buffer.buffer is set to NULL.
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*/
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for (;;) {
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free(description);
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if ((description = malloc(descrlen)) != NULL) {
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ifrdesc.ifr_buffer.buffer = description;
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ifrdesc.ifr_buffer.length = descrlen;
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if (ioctl(s, SIOCGIFDESCR, &ifrdesc) == 0) {
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if (ifrdesc.ifr_buffer.buffer ==
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description)
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break;
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else
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descrlen = ifrdesc.ifr_buffer.length;
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} else {
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/*
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* Failed to get interface description.
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*/
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free(description);
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description = NULL;
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break;
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}
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} else
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break;
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}
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#else /* __FreeBSD__ */
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/*
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* The only other OS that currently supports
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* SIOCGIFDESCR is OpenBSD, and it has no way
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* to get the description length - it's clamped
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* to a maximum of IFDESCRSIZE.
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*/
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if ((description = malloc(descrlen)) != NULL) {
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ifrdesc.ifr_data = (caddr_t)description;
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if (ioctl(s, SIOCGIFDESCR, &ifrdesc) != 0) {
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/*
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* Failed to get interface description.
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*/
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free(description);
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description = NULL;
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}
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}
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#endif /* __FreeBSD__ */
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close(s);
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if (description != NULL && strlen(description) == 0) {
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/*
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* Description is empty, so discard it.
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*/
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free(description);
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description = NULL;
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}
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}
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#ifdef __FreeBSD__
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/*
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* For FreeBSD, if we didn't get a description, and this is
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* a device with a name of the form usbusN, label it as a USB
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* bus.
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*/
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if (description == NULL) {
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if (strncmp(name, "usbus", 5) == 0) {
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/*
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* OK, it begins with "usbus".
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*/
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long busnum;
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char *p;
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errno = 0;
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busnum = strtol(name + 5, &p, 10);
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if (errno == 0 && p != name + 5 && *p == '\0' &&
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busnum >= 0 && busnum <= INT_MAX) {
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/*
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* OK, it's a valid number that's not
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* bigger than INT_MAX. Construct
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* a description from it.
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*/
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static const char descr_prefix[] = "USB bus number ";
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size_t descr_size;
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/*
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* Allow enough room for a 32-bit bus number.
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* sizeof (descr_prefix) includes the
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* terminating NUL.
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*/
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descr_size = sizeof (descr_prefix) + 10;
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description = malloc(descr_size);
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if (description != NULL) {
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pcap_snprintf(description, descr_size,
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"%s%ld", descr_prefix, busnum);
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}
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}
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}
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}
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#endif
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return (description);
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#else /* SIOCGIFDESCR */
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return (NULL);
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#endif /* SIOCGIFDESCR */
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}
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/*
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* Look for a given device in the specified list of devices.
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*
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* If we find it, return 0 and set *curdev_ret to point to it.
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*
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* If we don't find it, check whether we can open it:
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*
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* If that fails with PCAP_ERROR_NO_SUCH_DEVICE or
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* PCAP_ERROR_IFACE_NOT_UP, don't attempt to add an entry for
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* it, as that probably means it exists but doesn't support
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* packet capture.
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*
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* Otherwise, attempt to add an entry for it, with the specified
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* ifnet flags and description, and, if that succeeds, return 0
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* and set *curdev_ret to point to the new entry, otherwise
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* return PCAP_ERROR and set errbuf to an error message. If we
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* weren't given a description, try to get one.
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*/
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int
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add_or_find_if(pcap_if_t **curdev_ret, pcap_if_t **alldevs, const char *name,
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bpf_u_int32 flags, const char *description, char *errbuf)
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{
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pcap_t *p;
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pcap_if_t *curdev, *prevdev, *nextdev;
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u_int this_figure_of_merit, nextdev_figure_of_merit;
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char open_errbuf[PCAP_ERRBUF_SIZE];
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int ret;
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/*
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* Is there already an entry in the list for this interface?
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*/
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for (curdev = *alldevs; curdev != NULL; curdev = curdev->next) {
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if (strcmp(name, curdev->name) == 0)
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break; /* yes, we found it */
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}
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if (curdev == NULL) {
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/*
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* No, we didn't find it.
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*
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* Can we open this interface for live capture?
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*
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* We do this check so that interfaces that are
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* supplied by the interface enumeration mechanism
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* we're using but that don't support packet capture
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* aren't included in the list. Loopback interfaces
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* on Solaris are an example of this; we don't just
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* omit loopback interfaces on all platforms because
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* you *can* capture on loopback interfaces on some
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* OSes.
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*
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* On OS X, we don't do this check if the device
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* name begins with "wlt"; at least some versions
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* of OS X offer monitor mode capturing by having
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* a separate "monitor mode" device for each wireless
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* adapter, rather than by implementing the ioctls
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* that {Free,Net,Open,DragonFly}BSD provide.
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* Opening that device puts the adapter into monitor
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* mode, which, at least for some adapters, causes
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* them to deassociate from the network with which
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* they're associated.
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*
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* Instead, we try to open the corresponding "en"
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||
|
* device (so that we don't end up with, for users
|
||
|
* without sufficient privilege to open capture
|
||
|
* devices, a list of adapters that only includes
|
||
|
* the wlt devices).
|
||
|
*/
|
||
|
#ifdef __APPLE__
|
||
|
if (strncmp(name, "wlt", 3) == 0) {
|
||
|
char *en_name;
|
||
|
size_t en_name_len;
|
||
|
|
||
|
/*
|
||
|
* Try to allocate a buffer for the "en"
|
||
|
* device's name.
|
||
|
*/
|
||
|
en_name_len = strlen(name) - 1;
|
||
|
en_name = malloc(en_name_len + 1);
|
||
|
if (en_name == NULL) {
|
||
|
(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
||
|
"malloc: %s", pcap_strerror(errno));
|
||
|
return (-1);
|
||
|
}
|
||
|
strcpy(en_name, "en");
|
||
|
strcat(en_name, name + 3);
|
||
|
p = pcap_create(en_name, open_errbuf);
|
||
|
free(en_name);
|
||
|
} else
|
||
|
#endif /* __APPLE */
|
||
|
p = pcap_create(name, open_errbuf);
|
||
|
if (p == NULL) {
|
||
|
/*
|
||
|
* The attempt to create the pcap_t failed;
|
||
|
* that's probably an indication that we're
|
||
|
* out of memory.
|
||
|
*
|
||
|
* Don't bother including this interface,
|
||
|
* but don't treat it as an error.
|
||
|
*/
|
||
|
*curdev_ret = NULL;
|
||
|
return (0);
|
||
|
}
|
||
|
/* Small snaplen, so we don't try to allocate much memory. */
|
||
|
pcap_set_snaplen(p, 68);
|
||
|
ret = pcap_activate(p);
|
||
|
pcap_close(p);
|
||
|
switch (ret) {
|
||
|
|
||
|
case PCAP_ERROR_NO_SUCH_DEVICE:
|
||
|
case PCAP_ERROR_IFACE_NOT_UP:
|
||
|
/*
|
||
|
* We expect these two errors - they're the
|
||
|
* reason we try to open the device.
|
||
|
*
|
||
|
* PCAP_ERROR_NO_SUCH_DEVICE typically means
|
||
|
* "there's no such device *known to the
|
||
|
* OS's capture mechanism*", so, even though
|
||
|
* it might be a valid network interface, you
|
||
|
* can't capture on it (e.g., the loopback
|
||
|
* device in Solaris up to Solaris 10, or
|
||
|
* the vmnet devices in OS X with VMware
|
||
|
* Fusion). We don't include those devices
|
||
|
* in our list of devices, as there's no
|
||
|
* point in doing so - they're not available
|
||
|
* for capture.
|
||
|
*
|
||
|
* PCAP_ERROR_IFACE_NOT_UP means that the
|
||
|
* OS's capture mechanism doesn't work on
|
||
|
* interfaces not marked as up; some capture
|
||
|
* mechanisms *do* support that, so we no
|
||
|
* longer reject those interfaces out of hand,
|
||
|
* but we *do* want to reject them if they
|
||
|
* can't be opened for capture.
|
||
|
*/
|
||
|
*curdev_ret = NULL;
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Yes, we can open it, or we can't, for some other
|
||
|
* reason.
|
||
|
*
|
||
|
* If we can open it, we want to offer it for
|
||
|
* capture, as you can capture on it. If we can't,
|
||
|
* we want to offer it for capture, so that, if
|
||
|
* the user tries to capture on it, they'll get
|
||
|
* an error and they'll know why they can't
|
||
|
* capture on it (e.g., insufficient permissions)
|
||
|
* or they'll report it as a problem (and then
|
||
|
* have the error message to provide as information).
|
||
|
*
|
||
|
* Allocate a new entry.
|
||
|
*/
|
||
|
curdev = malloc(sizeof(pcap_if_t));
|
||
|
if (curdev == NULL) {
|
||
|
(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
||
|
"malloc: %s", pcap_strerror(errno));
|
||
|
return (-1);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Fill in the entry.
|
||
|
*/
|
||
|
curdev->next = NULL;
|
||
|
curdev->name = strdup(name);
|
||
|
if (curdev->name == NULL) {
|
||
|
(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
||
|
"malloc: %s", pcap_strerror(errno));
|
||
|
free(curdev);
|
||
|
return (-1);
|
||
|
}
|
||
|
if (description == NULL) {
|
||
|
/*
|
||
|
* We weren't handed a description for the
|
||
|
* interface, so see if we can generate one
|
||
|
* ourselves.
|
||
|
*/
|
||
|
curdev->description = get_if_description(name);
|
||
|
} else {
|
||
|
/*
|
||
|
* We were handed a description; make a copy.
|
||
|
*/
|
||
|
curdev->description = strdup(description);
|
||
|
if (curdev->description == NULL) {
|
||
|
(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
||
|
"malloc: %s", pcap_strerror(errno));
|
||
|
free(curdev->name);
|
||
|
free(curdev);
|
||
|
return (-1);
|
||
|
}
|
||
|
}
|
||
|
curdev->addresses = NULL; /* list starts out as empty */
|
||
|
curdev->flags = flags;
|
||
|
|
||
|
/*
|
||
|
* Add it to the list, in the appropriate location.
|
||
|
* First, get the "figure of merit" for this
|
||
|
* interface.
|
||
|
*/
|
||
|
this_figure_of_merit = get_figure_of_merit(curdev);
|
||
|
|
||
|
/*
|
||
|
* Now look for the last interface with an figure of merit
|
||
|
* less than or equal to the new interface's figure of
|
||
|
* merit.
|
||
|
*
|
||
|
* We start with "prevdev" being NULL, meaning we're before
|
||
|
* the first element in the list.
|
||
|
*/
|
||
|
prevdev = NULL;
|
||
|
for (;;) {
|
||
|
/*
|
||
|
* Get the interface after this one.
|
||
|
*/
|
||
|
if (prevdev == NULL) {
|
||
|
/*
|
||
|
* The next element is the first element.
|
||
|
*/
|
||
|
nextdev = *alldevs;
|
||
|
} else
|
||
|
nextdev = prevdev->next;
|
||
|
|
||
|
/*
|
||
|
* Are we at the end of the list?
|
||
|
*/
|
||
|
if (nextdev == NULL) {
|
||
|
/*
|
||
|
* Yes - we have to put the new entry
|
||
|
* after "prevdev".
|
||
|
*/
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Is the new interface's figure of merit less
|
||
|
* than the next interface's figure of merit,
|
||
|
* meaning that the new interface is better
|
||
|
* than the next interface?
|
||
|
*/
|
||
|
nextdev_figure_of_merit = get_figure_of_merit(nextdev);
|
||
|
if (this_figure_of_merit < nextdev_figure_of_merit) {
|
||
|
/*
|
||
|
* Yes - we should put the new entry
|
||
|
* before "nextdev", i.e. after "prevdev".
|
||
|
*/
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
prevdev = nextdev;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Insert before "nextdev".
|
||
|
*/
|
||
|
curdev->next = nextdev;
|
||
|
|
||
|
/*
|
||
|
* Insert after "prevdev" - unless "prevdev" is null,
|
||
|
* in which case this is the first interface.
|
||
|
*/
|
||
|
if (prevdev == NULL) {
|
||
|
/*
|
||
|
* This is the first interface. Pass back a
|
||
|
* pointer to it, and put "curdev" before
|
||
|
* "nextdev".
|
||
|
*/
|
||
|
*alldevs = curdev;
|
||
|
} else
|
||
|
prevdev->next = curdev;
|
||
|
}
|
||
|
|
||
|
*curdev_ret = curdev;
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Try to get a description for a given device, and then look for that
|
||
|
* device in the specified list of devices.
|
||
|
*
|
||
|
* If we find it, then, if the specified address isn't null, add it to
|
||
|
* the list of addresses for the device and return 0.
|
||
|
*
|
||
|
* If we don't find it, check whether we can open it:
|
||
|
*
|
||
|
* If that fails with PCAP_ERROR_NO_SUCH_DEVICE or
|
||
|
* PCAP_ERROR_IFACE_NOT_UP, don't attempt to add an entry for
|
||
|
* it, as that probably means it exists but doesn't support
|
||
|
* packet capture.
|
||
|
*
|
||
|
* Otherwise, attempt to add an entry for it, with the specified
|
||
|
* ifnet flags, and, if that succeeds, add the specified address
|
||
|
* to its list of addresses if that address is non-null, set
|
||
|
* *curdev_ret to point to the new entry, and return 0, otherwise
|
||
|
* return PCAP_ERROR and set errbuf to an error message.
|
||
|
*
|
||
|
* (We can get called with a null address because we might get a list
|
||
|
* of interface name/address combinations from the underlying OS, with
|
||
|
* the address being absent in some cases, rather than a list of
|
||
|
* interfaces with each interface having a list of addresses, so this
|
||
|
* call may be the only call made to add to the list, and we want to
|
||
|
* add interfaces even if they have no addresses.)
|
||
|
*/
|
||
|
int
|
||
|
add_addr_to_iflist(pcap_if_t **alldevs, const char *name, bpf_u_int32 flags,
|
||
|
struct sockaddr *addr, size_t addr_size,
|
||
|
struct sockaddr *netmask, size_t netmask_size,
|
||
|
struct sockaddr *broadaddr, size_t broadaddr_size,
|
||
|
struct sockaddr *dstaddr, size_t dstaddr_size,
|
||
|
char *errbuf)
|
||
|
{
|
||
|
pcap_if_t *curdev;
|
||
|
|
||
|
if (add_or_find_if(&curdev, alldevs, name, flags, NULL, errbuf) == -1) {
|
||
|
/*
|
||
|
* Error - give up.
|
||
|
*/
|
||
|
return (-1);
|
||
|
}
|
||
|
if (curdev == NULL) {
|
||
|
/*
|
||
|
* Device wasn't added because it can't be opened.
|
||
|
* Not a fatal error.
|
||
|
*/
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
if (addr == NULL) {
|
||
|
/*
|
||
|
* There's no address to add; this entry just meant
|
||
|
* "here's a new interface".
|
||
|
*/
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* "curdev" is an entry for this interface, and we have an
|
||
|
* address for it; add an entry for that address to the
|
||
|
* interface's list of addresses.
|
||
|
*
|
||
|
* Allocate the new entry and fill it in.
|
||
|
*/
|
||
|
return (add_addr_to_dev(curdev, addr, addr_size, netmask,
|
||
|
netmask_size, broadaddr, broadaddr_size, dstaddr,
|
||
|
dstaddr_size, errbuf));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Add an entry to the list of addresses for an interface.
|
||
|
* "curdev" is the entry for that interface.
|
||
|
* If this is the first IP address added to the interface, move it
|
||
|
* in the list as appropriate.
|
||
|
*/
|
||
|
int
|
||
|
add_addr_to_dev(pcap_if_t *curdev,
|
||
|
struct sockaddr *addr, size_t addr_size,
|
||
|
struct sockaddr *netmask, size_t netmask_size,
|
||
|
struct sockaddr *broadaddr, size_t broadaddr_size,
|
||
|
struct sockaddr *dstaddr, size_t dstaddr_size,
|
||
|
char *errbuf)
|
||
|
{
|
||
|
pcap_addr_t *curaddr, *prevaddr, *nextaddr;
|
||
|
|
||
|
curaddr = malloc(sizeof(pcap_addr_t));
|
||
|
if (curaddr == NULL) {
|
||
|
(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
||
|
"malloc: %s", pcap_strerror(errno));
|
||
|
return (-1);
|
||
|
}
|
||
|
|
||
|
curaddr->next = NULL;
|
||
|
if (addr != NULL) {
|
||
|
curaddr->addr = dup_sockaddr(addr, addr_size);
|
||
|
if (curaddr->addr == NULL) {
|
||
|
(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
||
|
"malloc: %s", pcap_strerror(errno));
|
||
|
free(curaddr);
|
||
|
return (-1);
|
||
|
}
|
||
|
} else
|
||
|
curaddr->addr = NULL;
|
||
|
|
||
|
if (netmask != NULL) {
|
||
|
curaddr->netmask = dup_sockaddr(netmask, netmask_size);
|
||
|
if (curaddr->netmask == NULL) {
|
||
|
(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
||
|
"malloc: %s", pcap_strerror(errno));
|
||
|
if (curaddr->addr != NULL)
|
||
|
free(curaddr->addr);
|
||
|
free(curaddr);
|
||
|
return (-1);
|
||
|
}
|
||
|
} else
|
||
|
curaddr->netmask = NULL;
|
||
|
|
||
|
if (broadaddr != NULL) {
|
||
|
curaddr->broadaddr = dup_sockaddr(broadaddr, broadaddr_size);
|
||
|
if (curaddr->broadaddr == NULL) {
|
||
|
(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
||
|
"malloc: %s", pcap_strerror(errno));
|
||
|
if (curaddr->netmask != NULL)
|
||
|
free(curaddr->netmask);
|
||
|
if (curaddr->addr != NULL)
|
||
|
free(curaddr->addr);
|
||
|
free(curaddr);
|
||
|
return (-1);
|
||
|
}
|
||
|
} else
|
||
|
curaddr->broadaddr = NULL;
|
||
|
|
||
|
if (dstaddr != NULL) {
|
||
|
curaddr->dstaddr = dup_sockaddr(dstaddr, dstaddr_size);
|
||
|
if (curaddr->dstaddr == NULL) {
|
||
|
(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
|
||
|
"malloc: %s", pcap_strerror(errno));
|
||
|
if (curaddr->broadaddr != NULL)
|
||
|
free(curaddr->broadaddr);
|
||
|
if (curaddr->netmask != NULL)
|
||
|
free(curaddr->netmask);
|
||
|
if (curaddr->addr != NULL)
|
||
|
free(curaddr->addr);
|
||
|
free(curaddr);
|
||
|
return (-1);
|
||
|
}
|
||
|
} else
|
||
|
curaddr->dstaddr = NULL;
|
||
|
|
||
|
/*
|
||
|
* Find the end of the list of addresses.
|
||
|
*/
|
||
|
for (prevaddr = curdev->addresses; prevaddr != NULL; prevaddr = nextaddr) {
|
||
|
nextaddr = prevaddr->next;
|
||
|
if (nextaddr == NULL) {
|
||
|
/*
|
||
|
* This is the end of the list.
|
||
|
*/
|
||
|
break;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if (prevaddr == NULL) {
|
||
|
/*
|
||
|
* The list was empty; this is the first member.
|
||
|
*/
|
||
|
curdev->addresses = curaddr;
|
||
|
} else {
|
||
|
/*
|
||
|
* "prevaddr" is the last member of the list; append
|
||
|
* this member to it.
|
||
|
*/
|
||
|
prevaddr->next = curaddr;
|
||
|
}
|
||
|
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Look for a given device in the specified list of devices.
|
||
|
*
|
||
|
* If we find it, return 0.
|
||
|
*
|
||
|
* If we don't find it, check whether we can open it:
|
||
|
*
|
||
|
* If that fails with PCAP_ERROR_NO_SUCH_DEVICE or
|
||
|
* PCAP_ERROR_IFACE_NOT_UP, don't attempt to add an entry for
|
||
|
* it, as that probably means it exists but doesn't support
|
||
|
* packet capture.
|
||
|
*
|
||
|
* Otherwise, attempt to add an entry for it, with the specified
|
||
|
* ifnet flags and description, and, if that succeeds, return 0
|
||
|
* and set *curdev_ret to point to the new entry, otherwise
|
||
|
* return PCAP_ERROR and set errbuf to an error message.
|
||
|
*/
|
||
|
int
|
||
|
pcap_add_if(pcap_if_t **devlist, const char *name, u_int flags,
|
||
|
const char *description, char *errbuf)
|
||
|
{
|
||
|
pcap_if_t *curdev;
|
||
|
|
||
|
return (add_or_find_if(&curdev, devlist, name, flags, description,
|
||
|
errbuf));
|
||
|
}
|
||
|
|
||
|
|
||
|
/*
|
||
|
* Free a list of interfaces.
|
||
|
*/
|
||
|
void
|
||
|
pcap_freealldevs(pcap_if_t *alldevs)
|
||
|
{
|
||
|
pcap_if_t *curdev, *nextdev;
|
||
|
pcap_addr_t *curaddr, *nextaddr;
|
||
|
|
||
|
for (curdev = alldevs; curdev != NULL; curdev = nextdev) {
|
||
|
nextdev = curdev->next;
|
||
|
|
||
|
/*
|
||
|
* Free all addresses.
|
||
|
*/
|
||
|
for (curaddr = curdev->addresses; curaddr != NULL; curaddr = nextaddr) {
|
||
|
nextaddr = curaddr->next;
|
||
|
if (curaddr->addr)
|
||
|
free(curaddr->addr);
|
||
|
if (curaddr->netmask)
|
||
|
free(curaddr->netmask);
|
||
|
if (curaddr->broadaddr)
|
||
|
free(curaddr->broadaddr);
|
||
|
if (curaddr->dstaddr)
|
||
|
free(curaddr->dstaddr);
|
||
|
free(curaddr);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Free the name string.
|
||
|
*/
|
||
|
free(curdev->name);
|
||
|
|
||
|
/*
|
||
|
* Free the description string, if any.
|
||
|
*/
|
||
|
if (curdev->description != NULL)
|
||
|
free(curdev->description);
|
||
|
|
||
|
/*
|
||
|
* Free the interface.
|
||
|
*/
|
||
|
free(curdev);
|
||
|
}
|
||
|
}
|