설명할 부분이 2개 있습니다. 첫 번째는 XINETD.CONF이고 두 번째는 /etc/xinetd.d입니다. tftp는 인증을 전혀 제공하지 않아 보안 위험이 있으므로 비활성화되어 있는지 확인해야 합니다. /etc/xinetd.d에서 명확하게 볼 수 있습니다.
-rw-r--r--. 1 root root 23 Feb 24 2017 tftp
tftp가 존재하지만 [FILE]:XINETD.CONF의 구성이 tftp에 대한 액세스를 비활성화하거나 제거하는지 확실하지 않습니다. 그러면 [FILE]: XINETD.CONF를 어떻게 해석합니까?
====================================================
[FILE]: XINETD.CONF
-rw-------. 1 root root 1022 Feb 24 2017 /etc/xinetd.conf
====================================================
#
# This is the master xinetd configuration file. Settings in the
# default section will be inherited by all service configurations
# unless explicitly overridden in the service configuration. See
# xinetd.conf in the man pages for a more detailed explanation of
# these attributes.
defaults
{
# The next two items are intended to be a quick access place to
# temporarily enable or disable services.
#
# enabled =
# disabled =
# Define general logging characteristics.
log_type = SYSLOG daemon info
log_on_failure = HOST
log_on_success = PID HOST DURATION EXIT
# Define access restriction defaults
#
# no_access =
# only_from =
# max_load = 0
cps = 50 10
instances = 50
per_source = 10
# Address and networking defaults
#
# bind =
# mdns = yes
v6only = no
# setup environmental attributes
#
# passenv =
groups = yes
umask = 002
# Generally, banners are not used. This sets up their global defaults
#
# banner =
# banner_fail =
# banner_success =
}
includedir /etc/xinetd.d
====================================================
/etc/xinetd.d
/etc/xinetd.d:
total 68
drwxr-xr-x. 2 root root 4096 Feb 24 2017 .
drwxr-xr-x. 102 root root 12288 Sep 9 02:31 ..
-rw-------. 1 root root 1198 Feb 24 2017 chargen-dgram
-rw-------. 1 root root 1159 Dec 16 2015 chargen-stream
-rw-------. 1 root root 1199 Feb 24 2017 daytime-dgram
-rw-------. 1 root root 1159 Dec 16 2015 daytime-stream
-rw-------. 1 root root 1198 Feb 24 2017 discard-dgram
-rw-------. 1 root root 1200 Feb 24 2017 discard-stream
-rw-------. 1 root root 1189 Feb 24 2017 echo-dgram
-rw-------. 1 root root 1150 Dec 16 2015 echo-stream
-rw-r--r--. 1 root root 332 Mar 28 2014 rsync
-rw-------. 1 root root 1253 Feb 24 2017 tcpmux-server
-rw-r--r--. 1 root root 23 Feb 24 2017 tftp
-rw-------. 1 root root 1149 Dec 16 2015 time-dgram
-rw-------. 1 root root 1150 Dec 16 2015 time-stream
답변1
이렇게 하면 서비스를 비활성화하는 데 도움이 됩니다. https://www.oreilly.com/library/view/linux-security-cookbook/0596003919/ch03s03.html
거의..tftp 파일을 열고 비활성화=예 옵션을 추가하세요.
service tftp
{
...
disable = yes
}