Static Host RNDIS IP by linux based USB Gadget device

Question

I have to make a RNDIS connection between a Linux based board and a host machine (it can be WinXP/Win7/Ubuntu, etc).

When I connect the board using RNDIS cable, all hosts recognize and start resolving the IP address. On the board side I have given a static IP by executing a command on startup

ifconfig usb0 169.254.1.1 netmask 255.255.0.0 up

but the host machine takes a long time to negotiate the RNDIS IP and every time comes up with some unpredictable IP such as 169.254.abc.xyz.

I want to assign a static RNDIS IP (say 169.254.1.2) to any host connected with this Linux board. Can somebody help me determine how I can achieve this? On the host side I don’t use any special RNDIS driver. The default USB-Ethernet driver gets downloaded. The Linux version is 2.3.62.

Answer 1

Ok .. I got the answer .... Actually we have to start a dhcp server over the interface usb0. So whenever USB host will try to seek the dhcp IP, dhcp server running at device and listning at usb0 interface will answer the call and assigned an IP. To fix an Ip just assing oly one IP in IP pool (which can be done in udhcpd.conf file)

start the server udhcpd as:

busybox udhcpd /etc/udhcpd.conf

Below is the sample of dhcpd.conf which I used:

# Sample udhcpd configuration file (/etc/udhcpd.conf)
# Values shown are defaults

# The start and end of the IP lease block
start       169.254.10.102
end     169.254.10.102

# The interface that udhcpd will use
interface   usb0

# The maximum number of leases (includes addresses reserved
# by OFFER's, DECLINE's, and ARP conflicts). Will be corrected
# if it's bigger than IP lease block, but it ok to make it
# smaller than lease block.
#max_leases 254

# The amount of time that an IP will be reserved (leased to nobody)
# if a DHCP decline message is received (seconds)
#decline_time   3600

# The amount of time that an IP will be reserved
# if an ARP conflict occurs (seconds)
#conflict_time  3600

# How long an offered address is reserved (seconds)
#offer_time 60

# If client asks for lease below this value, it will be rounded up
# to this value (seconds)
#min_lease  60

# The location of the pid file
#pidfile    /var/run/udhcpd.pid

# The location of the leases file
#lease_file /var/lib/misc/udhcpd.leases

# The time period at which udhcpd will write out leases file.
# If this is 0, udhcpd will never automatically write leases file.
# Specified in seconds.
#auto_time  7200

# Every time udhcpd writes a leases file, the below script will be called
#notify_file            # default: no script
#notify_file    dumpleases  # useful for debugging

# The following are bootp specific options
# next server to use in bootstrap
#siaddr     192.168.0.22    # default: 0.0.0.0 (none)
# tftp server name
#sname      zorak       # default: none
# tftp file to download (e.g. kernel image)
#boot_file  /var/nfs_root   # default: none

# Static leases map
#static_lease 00:60:08:11:CE:4E 192.168.0.54
#static_lease 00:60:08:11:CE:3E 192.168.0.44

# The remainder of options are DHCP options and can be specified with the
# keyword 'opt' or 'option'. If an option can take multiple items, such
# as the dns option, they can be listed on the same line, or multiple
# lines.
# Examples:
#opt    dns 192.168.10.2 192.168.10.10
option  subnet  255.255.255.0
#opt    router  192.168.10.2
#opt    wins    192.168.10.10
#option dns 129.219.13.81   # appended to above DNS servers for a total of 3
option  domain  local
option  lease   864000      # default: 10 days
#option msstaticroutes  10.0.0.0/8 10.127.0.1       # single static route
#option staticroutes    10.0.0.0/8 10.127.0.1, 10.11.12.0/24 10.11.12.1
# Arbitrary option in hex form:
option  0x08    01020304    # option 8: "cookie server IP addr: 1.2.3.4"

# Currently supported options (for more info, see options.c):
#opt lease      NUM
#opt subnet     IP
#opt broadcast  IP
#opt router     IP_LIST
#opt ipttl      NUM
#opt mtu        NUM
#opt hostname   STRING      # client's hostname
#opt domain     STRING      # client's domain suffix
#opt search     STRING_LIST # search domains
#opt nisdomain  STRING
#opt timezone   NUM     # (localtime - UTC_time) in seconds. signed
#opt tftp       STRING      # tftp server name
#opt bootfile   STRING      # tftp file to download (e.g. kernel image)
#opt bootsize   NUM     # size of that file
#opt rootpath   STRING      # (NFS) path to mount as root fs
#opt wpad       STRING
#opt serverid   IP      # default: server's IP
#opt message    STRING      # error message (udhcpd sends it on success too)
#opt vlanid     NUM     # 802.1P VLAN ID
#opt vlanpriority NUM       # 802.1Q VLAN priority
# Options specifying server(s)
#opt dns        IP_LIST
#opt wins       IP_LIST
#opt nissrv     IP_LIST
#opt ntpsrv     IP_LIST
#opt lprsrv     IP_LIST
#opt swapsrv    IP
# Options specifying routes
#opt routes     IP_PAIR_LIST
#opt staticroutes   STATIC_ROUTES # RFC 3442 classless static route option
#opt msstaticroutes STATIC_ROUTES # same, using MS option number
# Obsolete options, no longer supported
#opt logsrv     IP_LIST # 704/UDP log server (not syslog!)
#opt namesrv    IP_LIST # IEN 116 name server, obsolete (August 1979!!!)
#opt cookiesrv  IP_LIST # RFC 865 "quote of the day" server, rarely (never?) used
#opt timesrv    IP_LIST # RFC 868 time server, rarely(never?) used
# TODO: in development
#opt userclass  STRING      # RFC 3004. set of LASCII strings. "I am a printer" etc
#opt sipserv    STRING LIST # RFC 3361. flag byte, then: 0: domain names, 1: IP addrs