PenTest/nmap
1
0
Fork 0
mirror of https://github.com/nmap/nmap.git synced 2025-12-24 00:19:01 +00:00
Code Issues Projects Releases Wiki Activity

Skip lease time in DHCP client packets by default

Browse Source 
The old behavior (of using the default time of 1s) did not allow constructing
packets without this option, which in turn resulted in (1) DHCPINFORM packets
being non-compliant with RFC 2131 and (2) DHCP discovery scripts potentially
receiving non-default IP lease information. Fixes #2197
This commit is contained in:
nnposter
2020-12-04 00:38:12 +00:00
parent d1b39a6003
commit 1293291ac8
2 changed files with 8 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
nselib/dhcp.lua
View File

@@ -396,7 +396,7 @@ end
--@param overrides [optional] A table of overrides. If a field in the table matches a field in the DHCP
-- packet (see rfc2131 section 2 for a list of possible fields), the value in the table
-- will be sent instead of the default value.
--@param lease_time [optional] The lease time used when requestint an IP. Default: 1 second.
--@param lease_time [optional] The lease time used when requesting an IP. Default: none.
--@param transaction_id The identity of the transaction.
--
--@return status (true or false)
@@ -444,7 +444,9 @@ function dhcp_build(request_type, ip_address, mac_address, options, request_opti
end
packet = packet .. string.pack(">Bs1", 0x37, request_options) -- Request options
packet = packet .. string.pack(">BBI4", 0x33, 4, lease_time or 1) -- Lease time
if lease_time then
packet = packet .. string.pack(">BBI4", 0x33, 4, lease_time) -- Lease time
end
packet = packet .. "\xFF" -- Termination
@@ -599,7 +601,7 @@ end
--@param overrides [optional] A table of overrides. If a field in the table matches a field in the DHCP
-- packet (see rfc2131 section 2 for a list of possible fields), the value in the table
-- will be sent instead of the default value.
--@param lease_time [optional] The lease time used when requestint an IP. Default: 1 second.
--@param lease_time [optional] The lease time used when requesting an IP. Default: none.
--@return status (true or false)
--@return The parsed response, as a table.
function make_request(target, request_type, ip_address, mac_address, options, request_options, overrides, lease_time)