From e46def834483ebd76282965a86e875c4cfacebca Mon Sep 17 00:00:00 2001 From: Christian Poessinger Date: Fri, 4 Dec 2020 20:06:25 +0100 Subject: dhcp: T3100: re-add range slicing support when exclude addresses are used Support was not yet present after the rewrite from commit 84b7ade2 ("dhcp: T3100: migrate server configuration to get_config_dict()") --- src/conf_mode/dhcp_server.py | 99 ++++++++++++++++++++++++-------------------- 1 file changed, 54 insertions(+), 45 deletions(-) (limited to 'src') diff --git a/src/conf_mode/dhcp_server.py b/src/conf_mode/dhcp_server.py index 6df9d4a25..9be586cdf 100755 --- a/src/conf_mode/dhcp_server.py +++ b/src/conf_mode/dhcp_server.py @@ -33,14 +33,14 @@ airbag.enable() config_file = '/run/dhcp-server/dhcpd.conf' -def dhcp_slice_range(exclude_list, range_list): +def dhcp_slice_range(exclude_list, range_dict): """ This function is intended to slice a DHCP range. What does it mean? Lets assume we have a DHCP range from '192.0.2.1' to '192.0.2.100' but want to exclude address '192.0.2.74' and '192.0.2.75'. We will - pass an input 'range_list' in the format: - [{'start' : '192.0.2.1', 'stop' : '192.0.2.100' }] + pass an input 'range_dict' in the format: + {'start' : '192.0.2.1', 'stop' : '192.0.2.100' } and we will receive an output list of: [{'start' : '192.0.2.1' , 'stop' : '192.0.2.73' }, {'start' : '192.0.2.76', 'stop' : '192.0.2.100' }] @@ -50,49 +50,49 @@ def dhcp_slice_range(exclude_list, range_list): output = [] # exclude list must be sorted for this to work exclude_list = sorted(exclude_list) - for ra in range_list: - range_start = ra['start'] - range_stop = ra['stop'] - range_last_exclude = '' - - for e in exclude_list: - if (ip_address(e) >= ip_address(range_start)) and \ - (ip_address(e) <= ip_address(range_stop)): - range_last_exclude = e - - for e in exclude_list: - if (ip_address(e) >= ip_address(range_start)) and \ - (ip_address(e) <= ip_address(range_stop)): - - # Build new IP address range ending one IP address before exclude address + range_start = range_dict['start'] + range_stop = range_dict['stop'] + range_last_exclude = '' + + for e in exclude_list: + if (ip_address(e) >= ip_address(range_start)) and \ + (ip_address(e) <= ip_address(range_stop)): + range_last_exclude = e + + for e in exclude_list: + if (ip_address(e) >= ip_address(range_start)) and \ + (ip_address(e) <= ip_address(range_stop)): + + # Build new address range ending one address before exclude address + r = { + 'start' : range_start, + 'stop' : str(ip_address(e) -1) + } + # On the next run our address range will start one address after + # the exclude address + range_start = str(ip_address(e) + 1) + + # on subsequent exclude addresses we can not + # append them to our output + if not (ip_address(r['start']) > ip_address(r['stop'])): + # Everything is fine, add range to result + output.append(r) + + # Take care of last IP address range spanning from the last exclude + # address (+1) to the end of the initial configured range + if ip_address(e) == ip_address(range_last_exclude): r = { - 'start' : range_start, - 'stop' : str(ip_address(e) -1) + 'start': str(ip_address(e) + 1), + 'stop': str(range_stop) } - # On the next run our IP address range will start one address after the exclude address - range_start = str(ip_address(e) + 1) - - # on subsequent exclude addresses we can not - # append them to our output if not (ip_address(r['start']) > ip_address(r['stop'])): - # Everything is fine, add range to result output.append(r) - - # Take care of last IP address range spanning from the last exclude - # address (+1) to the end of the initial configured range - if ip_address(e) == ip_address(range_last_exclude): - r = { - 'start': str(ip_address(e) + 1), - 'stop': str(range_stop) - } - if not (ip_address(r['start']) > ip_address(r['stop'])): - output.append(r) - else: - # if we have no exclude in the whole range - we just take the range - # as it is - if not range_last_exclude: - if ra not in output: - output.append(ra) + else: + # if we have no exclude in the whole range - we just take the range + # as it is + if not range_last_exclude: + if ra not in output: + output.append(ra) return output @@ -101,23 +101,32 @@ def get_config(config=None): conf = config else: conf = Config() - base = ['service', 'dhcp-server'] if not conf.exists(base): return None dhcp = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True) - # T2665: defaults include lease time per TAG node which need to be added to # individual subnet definitions default_values = defaults(base + ['shared-network-name', 'subnet']) for network, network_config in (dict_search('shared_network_name', dhcp).items() or {}): - print(network) for subnet, subnet_config in (dict_search('subnet', network_config).items() or {}): if 'lease' not in subnet_config: dhcp['shared_network_name'][network]['subnet'][subnet] = dict_merge( default_values, dhcp['shared_network_name'][network]['subnet'][subnet]) + # If exclude IP addresses are defined we need to slice them out of + # the defined ranges + if {'exclude', 'range'} <= set(subnet_config): + new_range_id = 0 + new_range_dict = {} + for r, r_config in subnet_config['range'].items(): + for slice in dhcp_slice_range(subnet_config['exclude'], r_config): + new_range_dict.update({new_range_id : slice}) + new_range_id +=1 + + subnet_config.update({'range' : new_range_dict}) + return dhcp def verify(dhcp): -- cgit v1.2.3