Hi Michael,
On 13.05.2011 10:13, Michael Tokarev wrote:
So basically, the only modification this patch provides is
to add -M option to specify alternative MAC address, right?
Yes
I think it should be addressed upstream first, or at least
tried to. I may take care of that.
That would be great!
But I've at least one comment about the code, see below.
This has 2 problems. First, you can't cast uint8_t to unsigned int*,
the result is at least endian-dependent (where's the byte of int which
should go to our uint8 -- in the end of int or at the beginning of it),
and sscanf will access bytes which are not within the hwmac array.
Second, if you make a mistake/typo in the mac address, it will be
silently ignored - at least a warning should be printed in this
case.
Thanks for the good feedback! Both problems should have been adressed in
the attached patches.
Regards,
Bjoern
diff -urN busybox-1.18.4/networking/udhcp/dhcpc.c
busybox-1.18.4-patched/networking/udhcp/dhcpc.c
--- busybox-1.18.4/networking/udhcp/dhcpc.c 2011-03-13 02:45:40.000000000
+0100
+++ busybox-1.18.4-patched/networking/udhcp/dhcpc.c 2011-05-13
12:10:25.007347099 +0200
@@ -856,6 +856,7 @@
//usage: "\n -i,--interface IFACE Interface to use (default eth0)"
//usage: "\n -p,--pidfile FILE Create pidfile"
//usage: "\n -s,--script PROG Run PROG at DHCP events
(default "CONFIG_UDHCPC_DEFAULT_SCRIPT")"
+//usage: "\n -M,--mac MAC MAC address to use instead of
HW MAC (example: 00:13:37:c0:ff:ee)"
//usage: "\n -t,--retries N Send up to N discover packets"
//usage: "\n -T,--timeout N Pause between packets (default
3 seconds)"
//usage: "\n -A,--tryagain N Wait N seconds after failure
(default 20)"
@@ -931,7 +932,8 @@
int udhcpc_main(int argc UNUSED_PARAM, char **argv)
{
uint8_t *temp, *message;
- const char *str_V, *str_h, *str_F, *str_r;
+ uint32_t hwmac[6];
+ const char *str_V, *str_h, *str_F, *str_r, *str_M;
IF_FEATURE_UDHCP_PORT(char *str_P;)
void *clientid_mac_ptr;
llist_t *list_O = NULL;
@@ -966,6 +968,7 @@
"release\0" No_argument "R"
"request\0" Required_argument "r"
"script\0" Required_argument "s"
+ "mac\0" Required_argument "M"
"timeout\0" Required_argument "T"
"version\0" No_argument "v"
"retries\0" Required_argument "t"
@@ -992,16 +995,17 @@
OPT_R = 1 << 9,
OPT_r = 1 << 10,
OPT_s = 1 << 11,
- OPT_T = 1 << 12,
- OPT_t = 1 << 13,
- OPT_S = 1 << 14,
- OPT_A = 1 << 15,
- OPT_O = 1 << 16,
- OPT_o = 1 << 17,
- OPT_x = 1 << 18,
- OPT_f = 1 << 19,
+ OPT_M = 1 << 12,
+ OPT_T = 1 << 13,
+ OPT_t = 1 << 14,
+ OPT_S = 1 << 15,
+ OPT_A = 1 << 16,
+ OPT_O = 1 << 17,
+ OPT_o = 1 << 18,
+ OPT_x = 1 << 19,
+ OPT_f = 1 << 20,
/* The rest has variable bit positions, need to be clever */
- OPTBIT_f = 19,
+ OPTBIT_f = 20,
USE_FOR_MMU( OPTBIT_b,)
IF_FEATURE_UDHCPC_ARPING(OPTBIT_a,)
IF_FEATURE_UDHCP_PORT( OPTBIT_P,)
@@ -1025,7 +1029,7 @@
#endif
;
IF_LONG_OPTS(applet_long_options = udhcpc_longopts;)
- opt = getopt32(argv, "CV:H:h:F:i:np:qRr:s:T:t:SA:O:ox:f"
+ opt = getopt32(argv, "CV:H:h:F:i:np:qRr:s:M:T:t:SA:O:ox:f"
USE_FOR_MMU("b")
IF_FEATURE_UDHCPC_ARPING("a")
IF_FEATURE_UDHCP_PORT("P:")
@@ -1033,6 +1037,7 @@
, &str_V, &str_h, &str_h, &str_F
, &client_config.interface, &client_config.pidfile, &str_r /*
i,p */
, &client_config.script /* s */
+ , &str_M /* M */
, &discover_timeout, &discover_retries, &tryagain_timeout /*
T,t,A */
, &list_O
, &list_x
@@ -1092,6 +1097,27 @@
return 1;
}
+ if (opt & (OPT_M)) {
+ int nrmacfields = sscanf(str_M,"%x:%x:%x:%x:%x:%x",
+ &hwmac[0],
+ &hwmac[1],
+ &hwmac[2],
+ &hwmac[3],
+ &hwmac[4],
+ &hwmac[5]);
+ if (nrmacfields == 6) {
+ for (int i = 0; i < 6; ++i) {
+ if (hwmac[i] > 255) {
+ bb_info_msg("Invalid MAC segment: %x,
exiting...", hwmac[i]);
+ return 1;
+ }
+ client_config.client_mac[i] = (uint8_t)
hwmac[i];
+ }
+ } else {
+ bb_info_msg("Invalid MAC address: %s, exiting...",
str_M);
+ return 1;
+ }
+ }
clientid_mac_ptr = NULL;
if (!(opt & OPT_C) && !udhcp_find_option(client_config.options,
DHCP_CLIENT_ID)) {
/* not suppressed and not set, set the default client ID */
diff -urN busybox-1.17.1-debianorig/include/usage.src.h
busybox-1.17.1-patched/include/usage.src.h
--- busybox-1.17.1-debianorig/include/usage.src.h 2010-07-25
00:12:43.000000000 +0200
+++ busybox-1.17.1-patched/include/usage.src.h 2011-05-12 14:47:10.601425094
+0200
@@ -4522,6 +4522,7 @@
"\n -p,--pidfile FILE Create pidfile" \
"\n -r,--request IP IP address to request" \
"\n -s,--script PROG Run PROG at DHCP events (default
"CONFIG_UDHCPC_DEFAULT_SCRIPT")" \
+ "\n -M,--mac MAC MAC address to use instead of HW MAC
(example: 00:13:37:c0:ff:ee)" \
"\n -t,--retries N Send up to N discover packets" \
"\n -T,--timeout N Pause between packets (default 3
seconds)" \
"\n -A,--tryagain N Wait N seconds after failure (default
20)" \
@@ -4553,6 +4554,7 @@
"\n -p FILE Create pidfile" \
"\n -r IP IP address to request" \
"\n -s PROG Run PROG at DHCP events (default
"CONFIG_UDHCPC_DEFAULT_SCRIPT")" \
+ "\n -M MAC MAC address to use instead of HW MAC (example:
00:13:37:c0:ff:ee)" \
"\n -t N Send up to N discover packets" \
"\n -T N Pause between packets (default 3 seconds)" \
"\n -A N Wait N seconds (default 20) after failure" \
diff -urN busybox-1.17.1-debianorig/networking/udhcp/dhcpc.c
busybox-1.17.1-patched/networking/udhcp/dhcpc.c
--- busybox-1.17.1-debianorig/networking/udhcp/dhcpc.c 2010-07-06
04:25:54.000000000 +0200
+++ busybox-1.17.1-patched/networking/udhcp/dhcpc.c 2011-05-13
12:05:21.370370159 +0200
@@ -766,7 +766,8 @@
int udhcpc_main(int argc UNUSED_PARAM, char **argv)
{
uint8_t *temp, *message;
- const char *str_c, *str_V, *str_h, *str_F, *str_r;
+ uint32_t hwmac[6];
+ const char *str_c, *str_V, *str_h, *str_F, *str_r, *str_M;
IF_FEATURE_UDHCP_PORT(char *str_P;)
llist_t *list_O = NULL;
llist_t *list_x = NULL;
@@ -801,6 +802,7 @@
"release\0" No_argument "R"
"request\0" Required_argument "r"
"script\0" Required_argument "s"
+ "mac\0" Required_argument "M"
"timeout\0" Required_argument "T"
"version\0" No_argument "v"
"retries\0" Required_argument "t"
@@ -828,16 +830,17 @@
OPT_R = 1 << 10,
OPT_r = 1 << 11,
OPT_s = 1 << 12,
- OPT_T = 1 << 13,
- OPT_t = 1 << 14,
- OPT_S = 1 << 15,
- OPT_A = 1 << 16,
- OPT_O = 1 << 17,
- OPT_o = 1 << 18,
- OPT_x = 1 << 19,
- OPT_f = 1 << 20,
+ OPT_M = 1 << 13,
+ OPT_T = 1 << 14,
+ OPT_t = 1 << 15,
+ OPT_S = 1 << 16,
+ OPT_A = 1 << 17,
+ OPT_O = 1 << 18,
+ OPT_o = 1 << 19,
+ OPT_x = 1 << 20,
+ OPT_f = 1 << 21,
/* The rest has variable bit positions, need to be clever */
- OPTBIT_f = 20,
+ OPTBIT_f = 21,
USE_FOR_MMU( OPTBIT_b,)
IF_FEATURE_UDHCPC_ARPING(OPTBIT_a,)
IF_FEATURE_UDHCP_PORT( OPTBIT_P,)
@@ -861,7 +864,7 @@
#endif
;
IF_LONG_OPTS(applet_long_options = udhcpc_longopts;)
- opt = getopt32(argv, "c:CV:H:h:F:i:np:qRr:s:T:t:SA:O:ox:f"
+ opt = getopt32(argv, "c:CV:H:h:F:i:np:qRr:s:M:T:t:SA:O:ox:f"
USE_FOR_MMU("b")
IF_FEATURE_UDHCPC_ARPING("a")
IF_FEATURE_UDHCP_PORT("P:")
@@ -869,6 +872,7 @@
, &str_c, &str_V, &str_h, &str_h, &str_F
, &client_config.interface, &client_config.pidfile, &str_r /*
i,p */
, &client_config.script /* s */
+ , &str_M /* M */
, &discover_timeout, &discover_retries, &tryagain_timeout /*
T,t,A */
, &list_O
, &list_x
@@ -928,6 +932,27 @@
return 1;
}
+ if (opt & (OPT_M)) {
+ int nrmacfields = sscanf(str_M,"%x:%x:%x:%x:%x:%x",
+ &hwmac[0],
+ &hwmac[1],
+ &hwmac[2],
+ &hwmac[3],
+ &hwmac[4],
+ &hwmac[5]);
+ if (nrmacfields == 6) {
+ for (int i = 0; i < 6; ++i) {
+ if (hwmac[i] > 255) {
+ bb_info_msg("Invalid MAC segment: %x,
exiting...", hwmac[i]);
+ return 1;
+ }
+ client_config.client_mac[i] = (uint8_t)
hwmac[i];
+ }
+ } else {
+ bb_info_msg("Invalid MAC address: %s, exiting...",
str_M);
+ return 1;
+ }
+ }
if (opt & OPT_c) {
client_config.clientid = alloc_dhcp_option(DHCP_CLIENT_ID,
str_c, 0);
} else if (!(opt & OPT_C)) {
