intersect

Intersection

Print only the IPs that appear in all input files.

Aliases: --common, --intersect, --intersect-all

How it works

Each input file is optimized, then the intersection is computed pairwise. An IP appears in the output only if it is covered by every input file. If the files have no overlap, the output is empty.

Examples

Find IPs common to two blocklists:

# list-a.txt          # list-b.txt
10.0.0.0/24           10.0.0.128/25
10.0.1.0/24           10.0.2.0/24
192.168.1.0/24        192.168.1.0/24

$ iprange --common list-a.txt list-b.txt
10.0.0.128/25
192.168.1.0/24

Only the upper half of 10.0.0.0/24 (which is 10.0.0.128/25) overlaps with list-b.txt's 10.0.0.128/25. 192.168.1.0/24 is in both files. 10.0.1.0/24 and 10.0.2.0/24 have no overlap and are excluded.

IPv6

$ printf '2001:db8::/32\n' > v6-a.txt
$ printf '2001:db8:1::/48\n2001:db9::/32\n' > v6-b.txt
$ iprange -6 --common v6-a.txt v6-b.txt
2001:db8:1::/48

The /32 in v6-a.txt contains the /48 from v6-b.txt. The 2001:db9::/32 in v6-b.txt does not overlap.