/etc/logrotate.d/samhain is in samhain 4.1.4-2build1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 | /var/log/samhain/samhain.log {
    weekly
    rotate 52
    nocreate
    missingok
    compress
    prerotate
        if test -f /var/run/samhain/samhain.pid; then \
          PIN=`cat /var/run/samhain/samhain.pid`; \
          /bin/kill -TTIN $PIN; \
          sleep 1; \
          AA=0; \
          while test "x$AA" != "x120"; do \
           AA=$(( AA + 1 )); \
           if test -f /var/log/samhain/samhain.log.lock; then \
             sleep 1; \
           else \
             break; \
           fi \
          done; \
        fi
    endscript
}
 |