From: Aaron Klingaman <alk@cs.princeton.edu>
Date: Thu, 28 Jul 2005 22:57:20 +0000 (+0000)
Subject: from
X-Git-Tag: BOOTMANAGER_PL_BOX_STABLE~16
X-Git-Url: http://git.onelab.eu/?p=bootmanager.git;a=commitdiff_plain;h=874e2525a59815be6a39e12f580337f9c44ff6cb

from
http://forums.devshed.com/archive/t-51149/Ethernet-card-address-Through-Python-or-C
add a function that will return the mac address for a given network device
---

diff --git a/source/utils.py b/source/utils.py
index b9a3746..5da5fcd 100644
--- a/source/utils.py
+++ b/source/utils.py
@@ -42,6 +42,10 @@
 
 import os, sys, shutil
 import popen2
+import socket
+import fcntl
+import string
+import exceptions
 
 from Exceptions import *
 
@@ -158,3 +162,32 @@ def removefile( filepath ):
 
     return 1
 
+
+
+# from: http://forums.devshed.com/archive/t-51149/
+#              Ethernet-card-address-Through-Python-or-C
+
+def hexy(n):
+    return "%02x" % (ord(n))
+
+def get_mac_from_interface(ifname):
+    """
+    given a device name, like eth0, return its mac_address.
+    return None if the device doesn't exist.
+    """
+    
+    SIOCGIFHWADDR = 0x8927 # magic number
+
+    s=socket.socket(socket.AF_INET,socket.SOCK_STREAM)
+    ifname = string.strip(ifname)
+    ifr = ifname + '\0'*(32-len(ifname))
+
+    try:
+        r= fcntl.ioctl(s.fileno(),SIOCGIFHWADDR,ifr)
+        addr = map(hexy,r[18:24])
+        ret = (':'.join(map(str, addr)))
+    except IOError, e:
+        ret = None
+        
+    return ret
+