plagmax aggregates prefixes in loose mode, in case where all subprefixes are also allowed. So in the output all subprefixes are ignored and neighbour prefixes are folded.

Example

Input:

10.0.0.0/24
10.0.1.0/24
10.0.2.0/24
10.0.2.1/32
10.0.3.0/24

Output:

10.0.0.0/22

plageq

plagmax aggregates prefixes in strict mode. So it does not add or remove prefixes, but aggregates sets of subprefixes with the same mask into larger prefixes with a submask. It tries to get the minimal number of prefixes in its output.

Example

Input:

10.0.0.0/24
10.0.1.0/24
10.0.2.0/24
10.0.2.1/32
10.0.3.0/24

Output:

10.0.0.0/22{24,24}
10.0.2.1/32

Building

You will need only a C compiler and a standard library to build the tools. A simple make run should do the job.

$ make
gcc -O3 -o lib.o -c lib.c
gcc -O3 -o plagmax plagmax.c lib.o
gcc -O3 -o plageq plageq.c lib.o

Running

The tools read stdin where they expect IP prefixes one per line. Prefixes are of the standard form: <IP>[/<mask>]. Both IPv4 and IPv6 are allowed, you can freely mix them and the input doesn't need to be sorted. Mask part is optional, in this case prefix is considered a single IP and the default of 32 for IPv4 and 128 for IPv6 is used.

plagmax outputs simple prefixes in the same format and plageq outputs prefixes with added submask range:
<IP>/<mask>{<low>,<high>}
This matches all prefixes, having masks in range <low>-<high> (inclusive) that lie inside the prefix <IP>/<mask>. In case <mask> = <low> = <high> the submasks part is omitted. This notation of submasks is used in bird routing daemon.

You can use bgpq4 tool for example to fetch the list of prefixes and pipe its output to the tools:

bgpq4 -4 -F '%n/%l\n' as-set-name | ./plageq > as-set-name.ipv4.strict.txt
bgpq4 -6 -F '%n/%l\n' as-set-name | ./plagmax > as-set-name.ipv6.loose.txt

Tools also output to stderr some statistics of using preallocated memory.