/usr/share/i2p/certificates/ is in i2p-router 0.9.34-1ubuntu3.
This file is owned by root:root, with mode 0o755.
..
/usr/share/i2p/certificates/family/
/usr/share/i2p/certificates/family/gostcoin.crt
/usr/share/i2p/certificates/family/i2p-dev.crt
/usr/share/i2p/certificates/family/i2pd-dev.crt
/usr/share/i2p/certificates/family/volatile.crt
/usr/share/i2p/certificates/i2cp/
/usr/share/i2p/certificates/i2ptunnel/
/usr/share/i2p/certificates/news/
/usr/share/i2p/certificates/news/ampernand_at_gmail.com.crt
/usr/share/i2p/certificates/news/echelon_at_mail.i2p.crt
/usr/share/i2p/certificates/news/str4d_at_mail.i2p.crt
/usr/share/i2p/certificates/news/zzz_at_mail.i2p.crt
/usr/share/i2p/certificates/plugin/
/usr/share/i2p/certificates/plugin/cacapo_at_mail.i2p.crt
/usr/share/i2p/certificates/plugin/str4d_at_mail.i2p.crt
/usr/share/i2p/certificates/plugin/zzz-plugin_at_mail.i2p.crt
/usr/share/i2p/certificates/reseed/
/usr/share/i2p/certificates/reseed/atomike_at_mail.i2p.crt
/usr/share/i2p/certificates/reseed/backup_at_mail.i2p.crt
/usr/share/i2p/certificates/reseed/bugme_at_mail.i2p.crt
/usr/share/i2p/certificates/reseed/creativecowpat_at_mail.i2p.crt
/usr/share/i2p/certificates/reseed/echelon_at_mail.i2p.crt
/usr/share/i2p/certificates/reseed/hottuna_at_mail.i2p.crt
/usr/share/i2p/certificates/reseed/igor_at_novg.net.crt
/usr/share/i2p/certificates/reseed/lazygravy_at_mail.i2p.crt
/usr/share/i2p/certificates/reseed/meeh_at_mail.i2p.crt
/usr/share/i2p/certificates/reseed/zmx_at_mail.i2p.crt
/usr/share/i2p/certificates/revocations/
/usr/share/i2p/certificates/router/
/usr/share/i2p/certificates/router/echelon_at_mail.i2p.crt
/usr/share/i2p/certificates/router/str4d_at_mail.i2p.crt
/usr/share/i2p/certificates/router/zzz_at_mail.i2p.crt
/usr/share/i2p/certificates/ssl/
/usr/share/i2p/certificates/ssl/echelon.reseed2017.crt
/usr/share/i2p/certificates/ssl/i2p.mooo.com.crt
/usr/share/i2p/certificates/ssl/i2pseed.creativecowpat.net.crt
/usr/share/i2p/certificates/ssl/isrgrootx1.crt
/usr/share/i2p/certificates/ssl/reseed.onion.im.crt