mirror of
https://gitlab.com/libvirt/libvirt.git
synced 2024-12-25 15:15:25 +00:00
e62cb4a9b7
Commit7e62c4cd26
(first appearing in libvirt-3.9.0 as a resolution to rhbz #1343919) added a "generated" attribute to virMacAddr that was set whenever a mac address was auto-generated by libvirt. This knowledge was used in a single place - when trying to match a NetDef from the Domain to Delete with user-provided XML. Since the XML parser always auto-generates a MAC address for NetDefs when none is provided, it was previously impossible to make a search where the MAC address isn't significant, but the addition of the "generated" attribute made it possible for the search function to ignore auto-generated MACs. This implementation had a problem though - it was adding a field to a "low level" struct - virMacAddr - which is used in other places with the assumption that it contains exactly a 6 byte MAC address and nothing else. In particular, virNWFilterSnoopEthHdr uses virMacAddr as part of the definition of an ethernet packet header, whose layout must of course match an actual ethernet packet. Adding the extra bools into virNWFilterSnoopEthHdr caused the nwfilter driver's "IP discovery via DHCP packet snooping" functionality to mysteriously stop working. In order to fix that behavior, and prevent potential future similar odd behavior, this patch moves the "generated" member out of virMacAddr (so that it is again really is just a MAC address) into virDomainNetDef, and sets it only when virDomainNetGenerateMAC() is called from virDomainNetDefParseXML() (which is the only time we care about it). Resolves: https://bugzilla.redhat.com/1529338 (It should also be applied to any maintenance branch that applies commit7e62c4cd26
and friends to resolve https://bugzilla.redhat.com/1343919) Signed-off-by: Laine Stump <laine@laine.org>
255 lines
6.1 KiB
C
255 lines
6.1 KiB
C
/*
|
|
* virmacaddr.c: MAC address handling
|
|
*
|
|
* Copyright (C) 2006-2013 Red Hat, Inc.
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library. If not, see
|
|
* <http://www.gnu.org/licenses/>.
|
|
*
|
|
* Authors:
|
|
* Daniel P. Berrange <berrange@redhat.com>
|
|
*/
|
|
|
|
#include <config.h>
|
|
|
|
#include <stdlib.h>
|
|
#include <stdio.h>
|
|
|
|
#include "c-ctype.h"
|
|
#include "virmacaddr.h"
|
|
#include "virrandom.h"
|
|
#include "virutil.h"
|
|
|
|
static const unsigned char virMacAddrBroadcastAddrRaw[VIR_MAC_BUFLEN] =
|
|
{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
|
|
|
|
/* Compare two MAC addresses, ignoring differences in case,
|
|
* as well as leading zeros.
|
|
*/
|
|
int
|
|
virMacAddrCompare(const char *p, const char *q)
|
|
{
|
|
unsigned char c, d;
|
|
do {
|
|
while (*p == '0' && c_isxdigit(p[1]))
|
|
++p;
|
|
while (*q == '0' && c_isxdigit(q[1]))
|
|
++q;
|
|
c = c_tolower(*p);
|
|
d = c_tolower(*q);
|
|
|
|
if (c == 0 || d == 0)
|
|
break;
|
|
|
|
++p;
|
|
++q;
|
|
} while (c == d);
|
|
|
|
if (UCHAR_MAX <= INT_MAX)
|
|
return c - d;
|
|
|
|
/* On machines where 'char' and 'int' are types of the same size, the
|
|
difference of two 'unsigned char' values - including the sign bit -
|
|
doesn't fit in an 'int'. */
|
|
return c > d ? 1 : c < d ? -1 : 0;
|
|
}
|
|
|
|
/**
|
|
* virMacAddrCmp:
|
|
* @mac1: pointer to 1st MAC address
|
|
* @mac2: pointer to 2nd MAC address
|
|
*
|
|
* Return 0 if MAC addresses are equal,
|
|
* < 0 if mac1 < mac2,
|
|
* > 0 if mac1 > mac2
|
|
*/
|
|
int
|
|
virMacAddrCmp(const virMacAddr *mac1, const virMacAddr *mac2)
|
|
{
|
|
return memcmp(mac1->addr, mac2->addr, VIR_MAC_BUFLEN);
|
|
}
|
|
|
|
/**
|
|
* virMacAddrCmpRaw:
|
|
* @mac1: pointer to 1st MAC address
|
|
* @mac2: pointer to 2nd MAC address in plain buffer
|
|
*
|
|
* Return 0 if MAC addresses are equal,
|
|
* < 0 if mac1 < mac2,
|
|
* > 0 if mac1 > mac2
|
|
*/
|
|
int
|
|
virMacAddrCmpRaw(const virMacAddr *mac1,
|
|
const unsigned char mac2[VIR_MAC_BUFLEN])
|
|
{
|
|
return memcmp(mac1->addr, mac2, VIR_MAC_BUFLEN);
|
|
}
|
|
|
|
/**
|
|
* virMacAddrSet
|
|
* @dst: pointer to destination
|
|
* @src: pointer to source
|
|
*
|
|
* Copy src to dst
|
|
*/
|
|
void
|
|
virMacAddrSet(virMacAddrPtr dst, const virMacAddr *src)
|
|
{
|
|
memcpy(dst, src, sizeof(*src));
|
|
}
|
|
|
|
/**
|
|
* virMacAddrSetRaw
|
|
* @dst: pointer to destination to hold MAC address
|
|
* @src: raw MAC address data
|
|
*
|
|
* Set the MAC address to the given value
|
|
*/
|
|
void
|
|
virMacAddrSetRaw(virMacAddrPtr dst, const unsigned char src[VIR_MAC_BUFLEN])
|
|
{
|
|
memcpy(dst->addr, src, VIR_MAC_BUFLEN);
|
|
}
|
|
|
|
/**
|
|
* virMacAddrGetRaw
|
|
* @src: pointer to MAC address
|
|
* @dst: pointer to raw memory to write MAC address into
|
|
*
|
|
* Copies the MAC address into raw memory
|
|
*/
|
|
void
|
|
virMacAddrGetRaw(const virMacAddr *src, unsigned char dst[VIR_MAC_BUFLEN])
|
|
{
|
|
memcpy(dst, src->addr, VIR_MAC_BUFLEN);
|
|
}
|
|
|
|
/**
|
|
* virMacAddrParse:
|
|
* @str: string representation of MAC address, e.g., "0:1E:FC:E:3a:CB"
|
|
* @addr: 6-byte MAC address
|
|
*
|
|
* Parse a MAC address
|
|
*
|
|
* Return 0 upon success, or -1 in case of error.
|
|
*/
|
|
int
|
|
virMacAddrParse(const char* str, virMacAddrPtr addr)
|
|
{
|
|
size_t i;
|
|
|
|
errno = 0;
|
|
for (i = 0; i < VIR_MAC_BUFLEN; i++) {
|
|
char *end_ptr;
|
|
unsigned long result;
|
|
|
|
/* This is solely to avoid accepting the leading
|
|
* space or "+" that strtoul would otherwise accept.
|
|
*/
|
|
if (!c_isxdigit(*str))
|
|
break;
|
|
|
|
result = strtoul(str, &end_ptr, 16); /* exempt from syntax-check */
|
|
|
|
if ((end_ptr - str) < 1 || 2 < (end_ptr - str) ||
|
|
(errno != 0) ||
|
|
(0xFF < result))
|
|
break;
|
|
|
|
addr->addr[i] = (unsigned char) result;
|
|
|
|
if ((i == 5) && (*end_ptr <= ' '))
|
|
return 0;
|
|
if (*end_ptr != ':')
|
|
break;
|
|
|
|
str = end_ptr + 1;
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
/* virMacAddrFormat
|
|
* Converts the binary mac address in addr into a NULL-terminated
|
|
* character string in str. It is assumed that the memory pointed to
|
|
* by str is at least VIR_MAC_STRING_BUFLEN bytes long.
|
|
*
|
|
* Returns a pointer to the resulting character string.
|
|
*/
|
|
const char *
|
|
virMacAddrFormat(const virMacAddr *addr,
|
|
char *str)
|
|
{
|
|
snprintf(str, VIR_MAC_STRING_BUFLEN,
|
|
"%02x:%02x:%02x:%02x:%02x:%02x",
|
|
addr->addr[0], addr->addr[1], addr->addr[2],
|
|
addr->addr[3], addr->addr[4], addr->addr[5]);
|
|
str[VIR_MAC_STRING_BUFLEN-1] = '\0';
|
|
return str;
|
|
}
|
|
|
|
/**
|
|
* virMacAddrParseHex:
|
|
* @str: string hexadecimal representation of MAC address, e.g., "F801EFCE3aCB"
|
|
* @addr: 6-byte MAC address
|
|
*
|
|
* Parse the hexadecimal representation of a MAC address
|
|
*
|
|
* Return 0 upon success, or -1 in case of error.
|
|
*/
|
|
int
|
|
virMacAddrParseHex(const char *str, virMacAddrPtr addr)
|
|
{
|
|
size_t i;
|
|
|
|
if (strspn(str, "0123456789abcdefABCDEF") != VIR_MAC_HEXLEN ||
|
|
str[VIR_MAC_HEXLEN])
|
|
return -1;
|
|
|
|
for (i = 0; i < VIR_MAC_BUFLEN; i++)
|
|
addr->addr[i] = (virHexToBin(str[2 * i]) << 4 |
|
|
virHexToBin(str[2 * i + 1]));
|
|
return 0;
|
|
}
|
|
|
|
void virMacAddrGenerate(const unsigned char prefix[VIR_MAC_PREFIX_BUFLEN],
|
|
virMacAddrPtr addr)
|
|
{
|
|
addr->addr[0] = prefix[0];
|
|
addr->addr[1] = prefix[1];
|
|
addr->addr[2] = prefix[2];
|
|
addr->addr[3] = virRandomBits(8);
|
|
addr->addr[4] = virRandomBits(8);
|
|
addr->addr[5] = virRandomBits(8);
|
|
}
|
|
|
|
/* The low order bit of the first byte is the "multicast" bit. */
|
|
bool
|
|
virMacAddrIsMulticast(const virMacAddr *mac)
|
|
{
|
|
return !!(mac->addr[0] & 1);
|
|
}
|
|
|
|
bool
|
|
virMacAddrIsUnicast(const virMacAddr *mac)
|
|
{
|
|
return !(mac->addr[0] & 1);
|
|
}
|
|
|
|
bool
|
|
virMacAddrIsBroadcastRaw(const unsigned char s[VIR_MAC_BUFLEN])
|
|
{
|
|
return memcmp(virMacAddrBroadcastAddrRaw, s, sizeof(*s)) == 0;
|
|
}
|