* [Qemu-devel] [PATCH] Random MAC address option
@ 2009-01-27 0:13 Pavel Vasilyev
2009-01-27 0:34 ` [Qemu-devel] [PATCH] Replace strcmp() by strncmp() Pavel Vasilyev
` (4 more replies)
0 siblings, 5 replies; 13+ messages in thread
From: Pavel Vasilyev @ 2009-01-27 0:13 UTC (permalink / raw)
To: qemu-devel
[-- Attachment #1.1: Type: text/plain, Size: 3818 bytes --]
Index: Makefile.target
===================================================================
--- Makefile.target (revision 6463)
+++ Makefile.target (working copy)
@@ -580,7 +580,8 @@
OBJS+= fdc.o mc146818rtc.o serial.o i8259.o i8254.o pcspk.o pc.o
OBJS+= cirrus_vga.o apic.o parallel.o acpi.o piix_pci.o
OBJS+= usb-uhci.o vmmouse.o vmport.o vmware_vga.o hpet.o
-CPPFLAGS += -DHAS_AUDIO -DHAS_AUDIO_CHOICE
+CPPFLAGS +=
+#-DHAS_AUDIO -DHAS_AUDIO_CHOICE
endif
ifeq ($(TARGET_BASE_ARCH), ppc)
CPPFLAGS += -DHAS_AUDIO -DHAS_AUDIO_CHOICE
Index: net.c
===================================================================
--- net.c (revision 6463)
+++ net.c (working copy)
@@ -122,6 +122,24 @@
static VLANState *first_vlan;
+unsigned long int random_mac_seed(void) {
+
+ unsigned long int seed = 0;
+ int fd;
+
+ fd = open("/dev/urandom", O_RDONLY);
+ if (fd == -1) {
+ perror("open");
+ return 0;
+ }
+ if (read(fd, &seed, sizeof (seed)) < 0) {
+ perror("read");
+ seed = 0;
+ }
+ if (close(fd))
+ perror("close");
+ return seed;
+}
/***********************************************************/
/* network device redirectors */
@@ -160,7 +178,7 @@
long int offset;
errno = 0;
- offset = strtol(p, &last_char, 0);
+ offset = strtol(p, &last_char, 0);
if (0 == errno && '\0' == *last_char &&
offset >= 0 && offset <= 0xFFFFFF) {
macaddr[3] = (offset & 0xFF0000) >> 16;
@@ -179,7 +197,7 @@
p++;
}
}
- return 0;
+ return 0;
}
return -1;
@@ -1576,15 +1594,27 @@
fprintf(stderr, "Too Many NICs\n");
return -1;
}
+
nd = &nd_table[nb_nics];
macaddr = nd->macaddr;
- macaddr[0] = 0x52;
- macaddr[1] = 0x54;
- macaddr[2] = 0x00;
- macaddr[3] = 0x12;
- macaddr[4] = 0x34;
- macaddr[5] = 0x56 + nb_nics;
+ if (strstr(p, "macrandom")) {
+ macaddr[0] = (uint8_t) (random_mac_seed() % 0x100);
+ macaddr[1] = (uint8_t) (random_mac_seed() % 0x100);
+ macaddr[2] = (uint8_t) (random_mac_seed() % 0x100);
+ macaddr[3] = (uint8_t) (random_mac_seed() % 0x100);
+ macaddr[4] = (uint8_t) (random_mac_seed() % 0x100);
+ macaddr[5] = (uint8_t) (random_mac_seed() % 0x100);
+
+ } else {
+ macaddr[0] = 0x52;
+ macaddr[1] = 0x54;
+ macaddr[2] = 0x00;
+ macaddr[3] = 0x12;
+ macaddr[4] = 0x34;
+ macaddr[5] = 0x56 + nb_nics;
+ }
+
if (get_param_value(buf, sizeof(buf), "macaddr", p)) {
if (parse_macaddr(macaddr, buf) < 0) {
fprintf(stderr, "invalid syntax for ethernet address\n");
@@ -1720,7 +1750,7 @@
const char *p;
char *q;
char device[64];
-
+
p = str;
q = device;
while (*p != '\0' && *p != ',') {
Index: net.h
===================================================================
--- net.h (revision 6463)
+++ net.h (working copy)
@@ -52,6 +52,8 @@
const char *default_model);
void qemu_handler_true(void *opaque);
+unsigned long int random_mac_seed(void);
+
void do_info_network(void);
int do_set_link(const char *name, const char *up_or_down);
Index: qemu-malloc.c
===================================================================
--- qemu-malloc.c (revision 6463)
+++ qemu-malloc.c (working copy)
@@ -35,7 +35,7 @@
void *qemu_malloc(size_t size)
{
- return malloc(size);
+ return calloc(1, size);
}
void *qemu_realloc(void *ptr, size_t size)
[-- Attachment #1.2: macrandom.patch --]
[-- Type: text/x-diff, Size: 3818 bytes --]
Index: Makefile.target
===================================================================
--- Makefile.target (revision 6463)
+++ Makefile.target (working copy)
@@ -580,7 +580,8 @@
OBJS+= fdc.o mc146818rtc.o serial.o i8259.o i8254.o pcspk.o pc.o
OBJS+= cirrus_vga.o apic.o parallel.o acpi.o piix_pci.o
OBJS+= usb-uhci.o vmmouse.o vmport.o vmware_vga.o hpet.o
-CPPFLAGS += -DHAS_AUDIO -DHAS_AUDIO_CHOICE
+CPPFLAGS +=
+#-DHAS_AUDIO -DHAS_AUDIO_CHOICE
endif
ifeq ($(TARGET_BASE_ARCH), ppc)
CPPFLAGS += -DHAS_AUDIO -DHAS_AUDIO_CHOICE
Index: net.c
===================================================================
--- net.c (revision 6463)
+++ net.c (working copy)
@@ -122,6 +122,24 @@
static VLANState *first_vlan;
+unsigned long int random_mac_seed(void) {
+
+ unsigned long int seed = 0;
+ int fd;
+
+ fd = open("/dev/urandom", O_RDONLY);
+ if (fd == -1) {
+ perror("open");
+ return 0;
+ }
+ if (read(fd, &seed, sizeof (seed)) < 0) {
+ perror("read");
+ seed = 0;
+ }
+ if (close(fd))
+ perror("close");
+ return seed;
+}
/***********************************************************/
/* network device redirectors */
@@ -160,7 +178,7 @@
long int offset;
errno = 0;
- offset = strtol(p, &last_char, 0);
+ offset = strtol(p, &last_char, 0);
if (0 == errno && '\0' == *last_char &&
offset >= 0 && offset <= 0xFFFFFF) {
macaddr[3] = (offset & 0xFF0000) >> 16;
@@ -179,7 +197,7 @@
p++;
}
}
- return 0;
+ return 0;
}
return -1;
@@ -1576,15 +1594,27 @@
fprintf(stderr, "Too Many NICs\n");
return -1;
}
+
nd = &nd_table[nb_nics];
macaddr = nd->macaddr;
- macaddr[0] = 0x52;
- macaddr[1] = 0x54;
- macaddr[2] = 0x00;
- macaddr[3] = 0x12;
- macaddr[4] = 0x34;
- macaddr[5] = 0x56 + nb_nics;
+ if (strstr(p, "macrandom")) {
+ macaddr[0] = (uint8_t) (random_mac_seed() % 0x100);
+ macaddr[1] = (uint8_t) (random_mac_seed() % 0x100);
+ macaddr[2] = (uint8_t) (random_mac_seed() % 0x100);
+ macaddr[3] = (uint8_t) (random_mac_seed() % 0x100);
+ macaddr[4] = (uint8_t) (random_mac_seed() % 0x100);
+ macaddr[5] = (uint8_t) (random_mac_seed() % 0x100);
+
+ } else {
+ macaddr[0] = 0x52;
+ macaddr[1] = 0x54;
+ macaddr[2] = 0x00;
+ macaddr[3] = 0x12;
+ macaddr[4] = 0x34;
+ macaddr[5] = 0x56 + nb_nics;
+ }
+
if (get_param_value(buf, sizeof(buf), "macaddr", p)) {
if (parse_macaddr(macaddr, buf) < 0) {
fprintf(stderr, "invalid syntax for ethernet address\n");
@@ -1720,7 +1750,7 @@
const char *p;
char *q;
char device[64];
-
+
p = str;
q = device;
while (*p != '\0' && *p != ',') {
Index: net.h
===================================================================
--- net.h (revision 6463)
+++ net.h (working copy)
@@ -52,6 +52,8 @@
const char *default_model);
void qemu_handler_true(void *opaque);
+unsigned long int random_mac_seed(void);
+
void do_info_network(void);
int do_set_link(const char *name, const char *up_or_down);
Index: qemu-malloc.c
===================================================================
--- qemu-malloc.c (revision 6463)
+++ qemu-malloc.c (working copy)
@@ -35,7 +35,7 @@
void *qemu_malloc(size_t size)
{
- return malloc(size);
+ return calloc(1, size);
}
void *qemu_realloc(void *ptr, size_t size)
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^ permalink raw reply [flat|nested] 13+ messages in thread* [Qemu-devel] [PATCH] Replace strcmp() by strncmp()
2009-01-27 0:13 [Qemu-devel] [PATCH] Random MAC address option Pavel Vasilyev
@ 2009-01-27 0:34 ` Pavel Vasilyev
2009-01-27 9:28 ` [Qemu-devel] " Jan Kiszka
2009-01-27 0:57 ` [Qemu-devel] [PATCH] Random MAC address option malc
` (3 subsequent siblings)
4 siblings, 1 reply; 13+ messages in thread
From: Pavel Vasilyev @ 2009-01-27 0:34 UTC (permalink / raw)
To: qemu-devel
[-- Attachment #1: Type: text/plain, Size: 1506 bytes --]
Possible SIGSEGV
Index: net.c
===================================================================
--- net.c (revision 6463)
+++ net.c (working copy)
@@ -1568,7 +1586,7 @@
if (get_param_value(buf, sizeof(buf), "name", p)) {
name = strdup(buf);
}
- if (!strcmp(device, "nic")) {
+ if (!strncmp(device, "nic", 3)) {
NICInfo *nd;
uint8_t *macaddr;
@@ -1601,13 +1630,13 @@
vlan->nb_guest_devs++;
ret = 0;
} else
- if (!strcmp(device, "none")) {
+ if (!strncmp(device, "none", 4)) {
/* does nothing. It is needed to signal that no network cards
are wanted */
ret = 0;
} else
#ifdef CONFIG_SLIRP
- if (!strcmp(device, "user")) {
+ if (!strncmp(device, "user", 4)) {
if (get_param_value(buf, sizeof(buf), "hostname", p)) {
pstrcpy(slirp_hostname, sizeof(slirp_hostname), buf);
}
@@ -1622,7 +1651,7 @@
} else
#endif
#ifdef _WIN32
- if (!strcmp(device, "tap")) {
+ if (!strncmp(device, "tap", 3)) {
char ifname[64];
if (get_param_value(ifname, sizeof(ifname), "ifname", p) <= 0) {
fprintf(stderr, "tap: no interface name\n");
@@ -1633,7 +1662,7 @@
} else
#elif defined (_AIX)
#else
- if (!strcmp(device, "tap")) {
+ if (!strncmp(device, "tap", 3)) {
char ifname[64];
char setup_script[1024], down_script[1024];
int fd;
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^ permalink raw reply [flat|nested] 13+ messages in thread* [Qemu-devel] Re: [PATCH] Replace strcmp() by strncmp()
2009-01-27 0:34 ` [Qemu-devel] [PATCH] Replace strcmp() by strncmp() Pavel Vasilyev
@ 2009-01-27 9:28 ` Jan Kiszka
2009-01-27 20:49 ` Pavel Vasilyev
2009-01-27 21:20 ` Pavel Vasilyev
0 siblings, 2 replies; 13+ messages in thread
From: Jan Kiszka @ 2009-01-27 9:28 UTC (permalink / raw)
To: pavel; +Cc: qemu-devel
Pavel Vasilyev wrote:
> Possible SIGSEGV
I would suggest studying some strncmp implementation and also thinking
about the case that 'device' is, say, "nics"...
Jan
>
> Index: net.c
> ===================================================================
> --- net.c (revision 6463)
> +++ net.c (working copy)
> @@ -1568,7 +1586,7 @@
> if (get_param_value(buf, sizeof(buf), "name", p)) {
> name = strdup(buf);
> }
> - if (!strcmp(device, "nic")) {
> + if (!strncmp(device, "nic", 3)) {
> NICInfo *nd;
> uint8_t *macaddr;
>
> @@ -1601,13 +1630,13 @@
> vlan->nb_guest_devs++;
> ret = 0;
> } else
> - if (!strcmp(device, "none")) {
> + if (!strncmp(device, "none", 4)) {
> /* does nothing. It is needed to signal that no network cards
> are wanted */
> ret = 0;
> } else
> #ifdef CONFIG_SLIRP
> - if (!strcmp(device, "user")) {
> + if (!strncmp(device, "user", 4)) {
> if (get_param_value(buf, sizeof(buf), "hostname", p)) {
> pstrcpy(slirp_hostname, sizeof(slirp_hostname), buf);
> }
> @@ -1622,7 +1651,7 @@
> } else
> #endif
> #ifdef _WIN32
> - if (!strcmp(device, "tap")) {
> + if (!strncmp(device, "tap", 3)) {
> char ifname[64];
> if (get_param_value(ifname, sizeof(ifname), "ifname", p) <= 0) {
> fprintf(stderr, "tap: no interface name\n");
> @@ -1633,7 +1662,7 @@
> } else
> #elif defined (_AIX)
> #else
> - if (!strcmp(device, "tap")) {
> + if (!strncmp(device, "tap", 3)) {
> char ifname[64];
> char setup_script[1024], down_script[1024];
> int fd;
>
>
--
Siemens AG, Corporate Technology, CT SE 2
Corporate Competence Center Embedded Linux
^ permalink raw reply [flat|nested] 13+ messages in thread* Re: [Qemu-devel] Re: [PATCH] Replace strcmp() by strncmp()
2009-01-27 9:28 ` [Qemu-devel] " Jan Kiszka
@ 2009-01-27 20:49 ` Pavel Vasilyev
2009-01-27 21:20 ` Pavel Vasilyev
1 sibling, 0 replies; 13+ messages in thread
From: Pavel Vasilyev @ 2009-01-27 20:49 UTC (permalink / raw)
To: qemu-devel
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On Tuesday 27 January 2009 12:28:55 Jan Kiszka wrote:
> Pavel Vasilyev wrote:
> > Possible SIGSEGV
>
> I would suggest studying some strncmp implementation and also thinking
> about the case that 'device' is, say, "nics"...
>
> Jan
>
strncasecmp(); ???
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^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [Qemu-devel] Re: [PATCH] Replace strcmp() by strncmp()
2009-01-27 9:28 ` [Qemu-devel] " Jan Kiszka
2009-01-27 20:49 ` Pavel Vasilyev
@ 2009-01-27 21:20 ` Pavel Vasilyev
1 sibling, 0 replies; 13+ messages in thread
From: Pavel Vasilyev @ 2009-01-27 21:20 UTC (permalink / raw)
To: qemu-devel
[-- Attachment #1: Type: text/plain, Size: 466 bytes --]
On Tuesday 27 January 2009 12:28:55 Jan Kiszka wrote:
> Pavel Vasilyev wrote:
> > Possible SIGSEGV
>
> I would suggest studying some strncmp implementation and also thinking
> about the case that 'device' is, say, "nics"...
1. "nics" is other option
2. strncmp() conforming with next standarts: SVID 3, POSIX, BSD 4.3, ISO 9899
3. For case insensitivity - use strncasecmp(), For OSes where there is no this
function, it is possible to use macro.
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^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [Qemu-devel] [PATCH] Random MAC address option
2009-01-27 0:13 [Qemu-devel] [PATCH] Random MAC address option Pavel Vasilyev
2009-01-27 0:34 ` [Qemu-devel] [PATCH] Replace strcmp() by strncmp() Pavel Vasilyev
@ 2009-01-27 0:57 ` malc
2009-01-27 10:05 ` Kevin Wolf
` (2 subsequent siblings)
4 siblings, 0 replies; 13+ messages in thread
From: malc @ 2009-01-27 0:57 UTC (permalink / raw)
To: pavel, qemu-devel
On Tue, 27 Jan 2009, Pavel Vasilyev wrote:
> Index: Makefile.target
> ===================================================================
> --- Makefile.target (revision 6463)
> +++ Makefile.target (working copy)
> @@ -580,7 +580,8 @@
> OBJS+= fdc.o mc146818rtc.o serial.o i8259.o i8254.o pcspk.o pc.o
> OBJS+= cirrus_vga.o apic.o parallel.o acpi.o piix_pci.o
> OBJS+= usb-uhci.o vmmouse.o vmport.o vmware_vga.o hpet.o
> -CPPFLAGS += -DHAS_AUDIO -DHAS_AUDIO_CHOICE
> +CPPFLAGS +=
> +#-DHAS_AUDIO -DHAS_AUDIO_CHOICE
> endif
> ifeq ($(TARGET_BASE_ARCH), ppc)
> CPPFLAGS += -DHAS_AUDIO -DHAS_AUDIO_CHOICE
I'm not quite sure how disabling audio relates to MAC addresses..
[..snip..]
> Index: qemu-malloc.c
> ===================================================================
> --- qemu-malloc.c (revision 6463)
> +++ qemu-malloc.c (working copy)
> @@ -35,7 +35,7 @@
>
> void *qemu_malloc(size_t size)
> {
> - return malloc(size);
> + return calloc(1, size);
> }
>
> void *qemu_realloc(void *ptr, size_t size)
>
Nor this..
--
mailto:av1474@comtv.ru
^ permalink raw reply [flat|nested] 13+ messages in thread* Re: [Qemu-devel] [PATCH] Random MAC address option
2009-01-27 0:13 [Qemu-devel] [PATCH] Random MAC address option Pavel Vasilyev
2009-01-27 0:34 ` [Qemu-devel] [PATCH] Replace strcmp() by strncmp() Pavel Vasilyev
2009-01-27 0:57 ` [Qemu-devel] [PATCH] Random MAC address option malc
@ 2009-01-27 10:05 ` Kevin Wolf
2009-01-27 10:15 ` Riku Voipio
2009-01-27 16:33 ` Paul Brook
4 siblings, 0 replies; 13+ messages in thread
From: Kevin Wolf @ 2009-01-27 10:05 UTC (permalink / raw)
To: pavel, qemu-devel
Pavel Vasilyev schrieb:
> Index: Makefile.target
> ===================================================================
> --- Makefile.target (revision 6463)
> +++ Makefile.target (working copy)
> @@ -580,7 +580,8 @@
> OBJS+= fdc.o mc146818rtc.o serial.o i8259.o i8254.o pcspk.o pc.o
> OBJS+= cirrus_vga.o apic.o parallel.o acpi.o piix_pci.o
> OBJS+= usb-uhci.o vmmouse.o vmport.o vmware_vga.o hpet.o
> -CPPFLAGS += -DHAS_AUDIO -DHAS_AUDIO_CHOICE
> +CPPFLAGS +=
> +#-DHAS_AUDIO -DHAS_AUDIO_CHOICE
> endif
> ifeq ($(TARGET_BASE_ARCH), ppc)
> CPPFLAGS += -DHAS_AUDIO -DHAS_AUDIO_CHOICE
> Index: net.c
> ===================================================================
> --- net.c (revision 6463)
> +++ net.c (working copy)
> @@ -122,6 +122,24 @@
>
> static VLANState *first_vlan;
>
> +unsigned long int random_mac_seed(void) {
> +
> + unsigned long int seed = 0;
> + int fd;
> +
> + fd = open("/dev/urandom", O_RDONLY);
How is that supposed to work on Windows? And what's wrong with rand()?
> + if (fd == -1) {
> + perror("open");
> + return 0;
> + }
> + if (read(fd, &seed, sizeof (seed)) < 0) {
> + perror("read");
> + seed = 0;
> + }
> + if (close(fd))
> + perror("close");
> + return seed;
> +}
> /***********************************************************/
> /* network device redirectors */
>
> @@ -160,7 +178,7 @@
> long int offset;
>
> errno = 0;
> - offset = strtol(p, &last_char, 0);
> + offset = strtol(p, &last_char, 0);
> if (0 == errno && '\0' == *last_char &&
> offset >= 0 && offset <= 0xFFFFFF) {
> macaddr[3] = (offset & 0xFF0000) >> 16;
> @@ -179,7 +197,7 @@
> p++;
> }
> }
> - return 0;
> + return 0;
> }
>
> return -1;
I don't think these whitespace changes should be there.
Kevin
^ permalink raw reply [flat|nested] 13+ messages in thread* Re: [Qemu-devel] [PATCH] Random MAC address option
2009-01-27 0:13 [Qemu-devel] [PATCH] Random MAC address option Pavel Vasilyev
` (2 preceding siblings ...)
2009-01-27 10:05 ` Kevin Wolf
@ 2009-01-27 10:15 ` Riku Voipio
2009-01-27 10:25 ` Daniel P. Berrange
2009-01-27 20:51 ` Pavel Vasilyev
2009-01-27 16:33 ` Paul Brook
4 siblings, 2 replies; 13+ messages in thread
From: Riku Voipio @ 2009-01-27 10:15 UTC (permalink / raw)
To: pavel, qemu-devel
On Tue, Jan 27, 2009 at 03:13:18AM +0300, Pavel Vasilyev wrote:
> + if (strstr(p, "macrandom")) {
I take this means -net macaddr=macrandom will give the random
macaddr after this patch? please document this magic in
qemu-doc.texi and --help.
^ permalink raw reply [flat|nested] 13+ messages in thread* Re: [Qemu-devel] [PATCH] Random MAC address option
2009-01-27 10:15 ` Riku Voipio
@ 2009-01-27 10:25 ` Daniel P. Berrange
2009-01-27 14:28 ` Ian Jackson
2009-01-27 20:51 ` Pavel Vasilyev
1 sibling, 1 reply; 13+ messages in thread
From: Daniel P. Berrange @ 2009-01-27 10:25 UTC (permalink / raw)
To: qemu-devel; +Cc: pavel
On Tue, Jan 27, 2009 at 12:15:41PM +0200, Riku Voipio wrote:
> On Tue, Jan 27, 2009 at 03:13:18AM +0300, Pavel Vasilyev wrote:
> > + if (strstr(p, "macrandom")) {
>
> I take this means -net macaddr=macrandom will give the random
> macaddr after this patch? please document this magic in
> qemu-doc.texi and --help.
Generating a random MAC address everytime you boot a guest seems like
a very odd thing todo. MAC addresses should be randomly generated
once, and then fixed for the duration of existance of that guest,
across reboots.If you generate a random MAC on every boot, the OS will
think its NIC has been removed, and a new one added on every boot.
Daniel
--
|: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :|
|: http://libvirt.org -o- http://virt-manager.org -o- http://ovirt.org :|
|: http://autobuild.org -o- http://search.cpan.org/~danberr/ :|
|: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|
^ permalink raw reply [flat|nested] 13+ messages in thread* Re: [Qemu-devel] [PATCH] Random MAC address option
2009-01-27 10:25 ` Daniel P. Berrange
@ 2009-01-27 14:28 ` Ian Jackson
0 siblings, 0 replies; 13+ messages in thread
From: Ian Jackson @ 2009-01-27 14:28 UTC (permalink / raw)
To: Daniel P. Berrange, qemu-devel; +Cc: pavel
Daniel P. Berrange writes ("Re: [Qemu-devel] [PATCH] Random MAC address option"):
> On Tue, Jan 27, 2009 at 12:15:41PM +0200, Riku Voipio wrote:
> > I take this means -net macaddr=macrandom will give the random
> > macaddr after this patch? please document this magic in
> > qemu-doc.texi and --help.
Surely `macaddr=macrandom' is tautologous ? What's wrong with
`macaddr=random' ?
> Generating a random MAC address everytime you boot a guest seems like
> a very odd thing todo. MAC addresses should be randomly generated
> once, and then fixed for the duration of existance of that guest,
> across reboots.If you generate a random MAC on every boot, the OS will
> think its NIC has been removed, and a new one added on every boot.
Whether or not this is a problem depends on your operating system.
Indeed having a new MAC address each time can have privacy advantages
in certain IPv6 configurations!
If you want the MAC address to be persistent, where should qemu store
the MAC address ?
Ian.
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [Qemu-devel] [PATCH] Random MAC address option
2009-01-27 10:15 ` Riku Voipio
2009-01-27 10:25 ` Daniel P. Berrange
@ 2009-01-27 20:51 ` Pavel Vasilyev
1 sibling, 0 replies; 13+ messages in thread
From: Pavel Vasilyev @ 2009-01-27 20:51 UTC (permalink / raw)
To: qemu-devel
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On Tuesday 27 January 2009 13:15:41 Riku Voipio wrote:
> On Tue, Jan 27, 2009 at 03:13:18AM +0300, Pavel Vasilyev wrote:
> > + if (strstr(p, "macrandom")) {
>
> I take this means -net macaddr=macrandom will give the random
> macaddr after this patch?
-net nic,macrandom
> please document this magic in
> qemu-doc.texi and --help.
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^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [Qemu-devel] [PATCH] Random MAC address option
2009-01-27 0:13 [Qemu-devel] [PATCH] Random MAC address option Pavel Vasilyev
` (3 preceding siblings ...)
2009-01-27 10:15 ` Riku Voipio
@ 2009-01-27 16:33 ` Paul Brook
2009-01-27 16:47 ` Anthony Liguori
4 siblings, 1 reply; 13+ messages in thread
From: Paul Brook @ 2009-01-27 16:33 UTC (permalink / raw)
To: qemu-devel, pavel
> + if (strstr(p, "macrandom")) {
I'm not convinced this is a useful feature.
We already allow the user to specify a mac address, so this feature can be
trivially implemented (and better supported) by a management app or simple
shell script.
In addition to the issues other people have raised, there's no validation that
the random value is actually a valid mac address, and no conflict resolution
to avoid duplicate addresses when multiple NICs are present.
Paul
^ permalink raw reply [flat|nested] 13+ messages in thread* Re: [Qemu-devel] [PATCH] Random MAC address option
2009-01-27 16:33 ` Paul Brook
@ 2009-01-27 16:47 ` Anthony Liguori
0 siblings, 0 replies; 13+ messages in thread
From: Anthony Liguori @ 2009-01-27 16:47 UTC (permalink / raw)
To: qemu-devel; +Cc: pavel
Paul Brook wrote:
>> + if (strstr(p, "macrandom")) {
>>
>
> I'm not convinced this is a useful feature.
>
> We already allow the user to specify a mac address, so this feature can be
> trivially implemented (and better supported) by a management app or simple
> shell script.
>
> In addition to the issues other people have raised, there's no validation that
> the random value is actually a valid mac address, and no conflict resolution
> to avoid duplicate addresses when multiple NICs are present.
>
I agree. It gives a false sense of security.
Regards,
Anthony Liguori
> Paul
>
>
>
^ permalink raw reply [flat|nested] 13+ messages in thread
end of thread, other threads:[~2009-01-27 21:21 UTC | newest]
Thread overview: 13+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2009-01-27 0:13 [Qemu-devel] [PATCH] Random MAC address option Pavel Vasilyev
2009-01-27 0:34 ` [Qemu-devel] [PATCH] Replace strcmp() by strncmp() Pavel Vasilyev
2009-01-27 9:28 ` [Qemu-devel] " Jan Kiszka
2009-01-27 20:49 ` Pavel Vasilyev
2009-01-27 21:20 ` Pavel Vasilyev
2009-01-27 0:57 ` [Qemu-devel] [PATCH] Random MAC address option malc
2009-01-27 10:05 ` Kevin Wolf
2009-01-27 10:15 ` Riku Voipio
2009-01-27 10:25 ` Daniel P. Berrange
2009-01-27 14:28 ` Ian Jackson
2009-01-27 20:51 ` Pavel Vasilyev
2009-01-27 16:33 ` Paul Brook
2009-01-27 16:47 ` Anthony Liguori
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