sha1 kernel debian

matteo@raver:~$ ssh saturno
Linux saturno 4.16.0-saturno #78 SMP Fri Apr 6 01:16:01 CEST 2018 x86_64

The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
Last login: Mon Apr 16 23:06:44 2018 from 192.168.85.6
matteo@saturno:~$ cd /tmp/
matteo@saturno:/tmp$ cat /etc/debian_version
9.4
matteo@saturno:/tmp$ dd if=/dev/urandom of=file.bin bs=1M count=2000
2000+0 records in
2000+0 records out
2097152000 bytes (2,1 GB, 2,0 GiB) copied, 8,35583 s, 251 MB/s
matteo@saturno:/tmp$ ldd /usr/bin/sha1sum
        linux-vdso.so.1 (0x00007ffcd3775000)
        libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f879704a000)
        /lib64/ld-linux-x86-64.so.2 (0x00007f87975f5000)
matteo@saturno:/tmp$ ldd sha1sum
        linux-vdso.so.1 (0x00007ffdcabda000)
        libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007feb1f91f000)
        /lib64/ld-linux-x86-64.so.2 (0x00007feb1fcbe000)
matteo@saturno:/tmp$ sha1sum --version
sha1sum (GNU coreutils) 8.26
Copyright (C) 2016 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by Ulrich Drepper, Scott Miller, and David Madore.
matteo@saturno:/tmp$ ./sha1sum --version
sha1sum (GNU coreutils) 8.29.24-e6017
Copyright (C) 2018 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by Ulrich Drepper, Scott Miller, and David Madore.
matteo@saturno:/tmp$ time sha1sum file.bin
869a41690e5bf5b126b3774d0c139b45235b97f4  file.bin

real    0m4,668s
user    0m4,476s
sys     0m0,190s
matteo@saturno:/tmp$ time ./sha1sum file.bin
869a41690e5bf5b126b3774d0c139b45235b97f4  file.bin

real    0m3,247s
user    0m0,000s
sys     0m3,247s
matteo@saturno:/tmp$ strace -e trace=file,network ./sha1sum file.bin
execve("./sha1sum", ["./sha1sum", "file.bin"], [/* 27 vars */]) = 0
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
access("/etc/ld.so.nohwcap", F_OK)      = -1 ENOENT (No such file or directory)
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
open("/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3
open("file.bin", O_RDONLY)              = 3
socket(AF_ALG, SOCK_SEQPACKET, 0)       = 4
bind(4, {sa_family=AF_ALG, sa_data="hash\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0sha1\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"}, 88) = 0
accept(4, NULL, NULL)                   = 5
sendfile(5, 3, NULL, 2147479552)        = 2097152000
869a41690e5bf5b126b3774d0c139b45235b97f4  file.bin
+++ exited with 0 +++