| = ! 관리방어 공간 51-56 |
| = |
| = \TableOfContents0 |
| = |
| = !! level 51 |
| = |
| = + 풀이 방법 |
| + # 실제 풀이 방법 확인;; |
| + # 세팅값들을 쭉~ |
| + |
| + - 실제 풀이 |
| + {{{ |
| + net.ipv4.conf.all.accept_source_route=0 |
| + net.ipv4.conf.all.send_redirects=0 |
| + net.ipv4.conf.all.accept_redirects=0 |
| + net.ipv4.conf.all.log_martians=1 |
| + net.ipv4.conf.all.rp_filter=2 |
| + net.ipv4.conf.all.bootp_relay=0 |
| + net.ipv4.conf.all.secure_redirects=0 |
| + net.ipv4.conf.all.proxy_arp=0 |
| + net.ipv4.conf.all.accept_soource_route=0 |
| + net.ipv4.conf.lo.accept_redirects=0 |
| + net.ipv4.conf.lo.accept_source_route=0 |
| + net.ipv4.conf.lo.rp_filter=2 |
| + net.ipv4.conf.lo.log_martians=1 |
| + net.ipv4.conf.lo.secure_redirects=0 |
| + net.ipv4.conf.lo.send_redirects=0 |
| + net.ipv4.conf.lo.proxy_arp=0 |
| + net.ipv4.conf.eth0.accept_redirects=0 |
| + net.ipv4.conf.eth0.accept_source_route=0 |
| + net.ipv4.conf.eth0.rp_filter=2 |
| + net.ipv4.conf.eth0.bootp_relay=0 |
| + net.ipv4.conf.eth0.log_martians=1 |
| + net.ipv4.conf.eth0.secure_redirects=0 |
| + net.ipv4.conf.eth0.send_redirects=0 |
| + net.ipv4.conf.eth0.proxy_arp=0 |
| + net.ipv4.conf.default.rp_filter=1 |
| + net.ipv4.conf.default.accept_redirects=0 |
| + net.ipv4.conf.default.accept_source_route=0 |
| + net.ipv4.conf.default.bootp_relay=0 |
| + net.ipv4.conf.default.log_martians=1 |
| + net.ipv4.conf.default.secure_redirects=0 |
| + net.ipv4.conf.default.send_redirects=0 |
| + net.ipv4.conf.default.proxy_arp=0 |
| + net.ipv4.icmp_echo_ignore_all=1 |
| + net.ipv4.icmp_echo_ignore_broadcasts=1 |
| + net.ipv4.tcp_max_syn_backlog=1024 |
| + net.ipv4.tcp_syncookies=1 |
| + net.ipv4.packet_forward=1 |
| + net.ipv4.ip_forward=0 |
| + net.ipv4.icmp_destunreach_rate=1 |
| + net.ipv4.icmp_echoreply_rate=1 |
| + net.ipv4.icmp_paramprob_rate=1 |
| + net.ipv4.icmp_timeexceed_rate=1 |
| + net.ipv4.ip_always_defrag=0 |
| + net.ipv4.tcp_syn_retries=3 |
| + net.ipv4.icmp_ignore_bogus_error_responses=1 |
| + net.ipv4.igmp_max_memberships=1 |
| + net.ipv4.ip_default_ttl=64 |
| + net.ipv4.ipfrag_time=15 |
| + net.ipv4.tcp_retries1=3 |
| + net.ipv4.tcp_retries2=7 |
| + net.ipv4.tcp_keepalive_time=30 |
| + net.ipv4.tcp_fin_timeout=30 |
| + net.ipv4.tcp_tw_buckets=720000 |
| + net.ipv4.tcp_keepalive_probes=2 |
| + net.ipv4.tcp_max_ka_probes=100 |
| + net.ipv4.ip_forword=0 |
| + }}} |
| + |
| + > pass = <font color=red></font> |
| + |
| + !! level 52 |
| + |
| + + 풀이 방법 |
| + # /etc/sudoers 파일 편집 |
| + |
| + - 실제 풀이 |
| + {{{ |
| + # vi /etc/sudoers |
| + |
| + # sudoers file. |
| + # |
| + # This file MUST be edited with the 'visudo' command as root. |
| + # |
| + # See the sudoers man page for the details on how to write a sudoers file. |
| + # |
| + # Host alias specification |
| + # User alias specification |
| + # Cmnd alias specification |
| + # Defaults specification |
| + # User privilege specification |
| + root ALL=(ALL) ALL |
| + # Uncomment to allow people in group wheel to run all commands |
| + # %wheel ALL=(ALL) ALL |
| + # Same thing without a password |
| + # %wheel ALL=(ALL) NOPASSWD: ALL |
| + # Samples |
| + # %users ALL=/sbin/mount /cdrom,/sbin/umount /cdrom |
| + # %users localhost=/sbin/shutdown -h now |
| + |
| + user_admin ALL=/usr/sbin/useradd // 추가 부분 |
| + |
| + "/etc/sudoers" 31 lines, 615 characters written |
| + # finish |
| + Success |
| + |
| + ※ 원래는 visudo명령어를 통해서 /etc/sudoers 를 편집해야 한다고 함 |
| + |
| + }}} |
| + |
| + > pass = <font color=red>oksudoers</font> |
| + |
| + !! level 53 |
| + |
| + + 풀이 방법 |
| + # /etc/mail/sendmail.cf 파일 SmtpGreetingMessage 내용 삭제 |
| + # /etc/mail/helpfile 삭제 |
| + # /etc/mail/sendmail.cf 파일 Local and Program Mailer specification 부분 변경 |
| + # /etc/mail/sendmail.cf 파일 MaxMessageSize 변경 |
| + # /etc/mail/sendmail.cf 파일 MaxRecipientsPerMessage 변경 |
| + |
| + - 실제 풀이 |
| + {{{ |
| + # rm /etc/mail/helpfile |
| + # vi sendmail.cf |
| + # SMTP initial login message (old $e macro) |
| + O SmtpGreetingMessage= |
| + |
| + Mlocal, P=/usr/bin/procmail, F=lsDFMAw5:/|@qSPfhn9, S=10/30, |
| + R=20/40,M=5000000, T=DNS/RFC822/X-Unix, A=procmail -Y -a $h -d $u |
| + |
| + # maximum message size |
| + O MaxMessageSize=5000000 |
| + |
| + # maximum number of recipients per SMTP envelope |
| + O MaxRecipientsPerMessage=20 |
| = # |
| + # ps |
| + PID TTY TIME CMD |
| + 15227 pts/11 0:00 bash |
| + 15230 pts/11 0:00 sendmail |
| + 15492 pts/11 0:00 ps |
| + # kill -1 15230 |
| + # finish |
| + Success. |
| + }}} |
| = |
| + > pass = <font color=red>sendmailhelpno</font> |
| + |
| + !! level 54 |
| + |
| + + 풀이 방법 |
| + # __ssh-keygen__ 명령어 사용 비밀키 공개키를 작성 |
| + # scp 통해서 공개키 authorized_key 생성 |
| + |
| = - 실제 풀이 |
| = {{{ |
| + # ssh-keygen -t rsa |
| + Generating public/private rsa key pair. |
| + Enter file in which to save the key (/.ssh/id_rsa):/.ssh/id_rsa |
| + Enter passphrase (empty for no passphrase): |
| + Enter same passphrase again: |
| + Your identification has been saved in /.ssh/id_rsa. |
| + Your public key has been saved in /.ssh/id_rsa.pub. |
| + The key fingerprint is: |
| + 8a:de:60:ff:20:6c:47:98:60:a1:55:61:e4:42:63:df root@mdsol |
| + # |
| + # ls -la |
| + 총 1002 |
| + drwxr-xr-x 2 root other 512 9월 16일 18:57 -p |
| + drwxr-xr-x 22 root root 512 9월 17일 21:02 . |
| + drwxr-xr-x 22 root root 512 9월 17일 21:02 .. |
| + -rw-r--r-- 1 root other 307 9월 17일 21:02 .profile |
| + d--------- 2 root other 512 9월 14일 17:44 .rhosts |
| + drwxrwxrwx 2 root other 512 9월 17일 21:03 .ssh |
| + drwxr-xr-x 2 root other 512 4월 21일 21:15 aa |
| + drwxr-xr-x 3 root other 512 4월 27일 11:49 backup |
| + drwxr-xr-x 3 root other 512 2004년 1월 31일 vsh |
| + # scp .ssh/id_rsa.pub pascal@PubHome:.ssh/authorized_keys |
| + Enter password: // 패스워드 cobol 입력 |
| + # |
| + # finish |
| + success |
| + }}} |
| = |
| + > pass = <font color=red>opensshkeygenok</font> |
| + |
| + !! level 55 |
| + |
| + + 풀이 방법 |
| + # find 옵션 -perm , -nouser , -type |
| + # rediection 사용 파일 생성 |
| + |
| + - 실제 풀이 |
| + {{{ |
| + # find / -perm 20 -o -print > /tmp/write.txt |
| + # find / -nouser > /tmp/no_own.txt |
| + # find / -type f \( -perm -004000 -o -perm -002000 \) > /tmp/suid.txt |
| + # finish |
| + please wait while the program checks your answer. This may take several minutes. |
| + checking write.txt |
| + checking no_own.txt |
| + checking suid.txt |
| + Success. |
| = }}} |
| = |
| + > pass = <font color=red>permissioncheckok</font> |
| + |
| + !! level 56 |
| + |
| + + 풀이 방법 |
| + # |
| + |
| + - 실제 풀이 |
| + {{{ |
| + |
| + }}} |
| + |
| = > pass = <font color=red></font> |
| - |
| - !! level 52 |
| - |
| - + 풀이 방법 |
| - # /etc/sudoers 파일 편집 |
| - |
| - - 실제 풀이 |
| - {{{ |
| - # vi /etc/sudoers |
| - |
| - # sudoers file. |
| - # |
| - # This file MUST be edited with the 'visudo' command as root. |
| - # |
| - # See the sudoers man page for the details on how to write a sudoers file. |
| - # |
| - # Host alias specification |
| - # User alias specification |
| - # Cmnd alias specification |
| - # Defaults specification |
| - # User privilege specification |
| - root ALL=(ALL) ALL |
| - # Uncomment to allow people in group wheel to run all commands |
| - # %wheel ALL=(ALL) ALL |
| - # Same thing without a password |
| - # %wheel ALL=(ALL) NOPASSWD: ALL |
| - # Samples |
| - # %users ALL=/sbin/mount /cdrom,/sbin/umount /cdrom |
| - # %users localhost=/sbin/shutdown -h now |
| - |
| - user_admin ALL=/usr/sbin/useradd // 추가 부분 |
| - |
| - "/etc/sudoers" 31 lines, 615 characters written |
| - # finish |
| - Success |
| - |
| - ※ 원래는 visudo명령어를 통해서 /etc/sudoers 를 편집해야 한다고 함 |
| - |
| - }}} |
| - |
| - > pass = <font color=red>oksudoers</font> |
| - |
| - !! level 53 |
| - |
| - + 풀이 방법 |
| - # /etc/mail/sendmail.cf 파일 SmtpGreetingMessage 내용 삭제 |
| - # /etc/mail/helpfile 삭제 |
| - # /etc/mail/sendmail.cf 파일 Local and Program Mailer specification 부분 변경 |
| - # /etc/mail/sendmail.cf 파일 MaxMessageSize 변경 |
| - # /etc/mail/sendmail.cf 파일 MaxRecipientsPerMessage 변경 |
| - |
| - - 실제 풀이 |
| - {{{ |
| - # rm /etc/mail/helpfile |
| - # vi sendmail.cf |
| - # SMTP initial login message (old $e macro) |
| - O SmtpGreetingMessage= |
| - |
| - Mlocal, P=/usr/bin/procmail, F=lsDFMAw5:/|@qSPfhn9, S=10/30, |
| - R=20/40,M=5000000, T=DNS/RFC822/X-Unix, A=procmail -Y -a $h -d $u |
| - |
| - # maximum message size |
| - O MaxMessageSize=5000000 |
| - |
| - # maximum number of recipients per SMTP envelope |
| - O MaxRecipientsPerMessage=20 |
| - # |
| - # ps |
| - PID TTY TIME CMD |
| - 15227 pts/11 0:00 bash |
| - 15230 pts/11 0:00 sendmail |
| - 15492 pts/11 0:00 ps |
| - # kill -1 15230 |
| - # finish |
| - Success. |
| - }}} |
| - |
| - > pass = <font color=red>sendmailhelpno</font> |
| - |
| - !! level 54 |
| - |
| - + 풀이 방법 |
| - # __ssh-keygen__ 명령어 사용 비밀키 공개키를 작성 |
| - # scp 통해서 공개키 authorized_key 생성 |
| - |
| - - 실제 풀이 |
| - {{{ |
| - # ssh-keygen -t rsa |
| - Generating public/private rsa key pair. |
| - Enter file in which to save the key (/.ssh/id_rsa):/.ssh/id_rsa |
| - Enter passphrase (empty for no passphrase): |
| - Enter same passphrase again: |
| - Your identification has been saved in /.ssh/id_rsa. |
| - Your public key has been saved in /.ssh/id_rsa.pub. |
| - The key fingerprint is: |
| - 8a:de:60:ff:20:6c:47:98:60:a1:55:61:e4:42:63:df root@mdsol |
| - # |
| - # ls -la |
| - 총 1002 |
| - drwxr-xr-x 2 root other 512 9월 16일 18:57 -p |
| - drwxr-xr-x 22 root root 512 9월 17일 21:02 . |
| - drwxr-xr-x 22 root root 512 9월 17일 21:02 .. |
| - -rw-r--r-- 1 root other 307 9월 17일 21:02 .profile |
| - d--------- 2 root other 512 9월 14일 17:44 .rhosts |
| - drwxrwxrwx 2 root other 512 9월 17일 21:03 .ssh |
| - drwxr-xr-x 2 root other 512 4월 21일 21:15 aa |
| - drwxr-xr-x 3 root other 512 4월 27일 11:49 backup |
| - drwxr-xr-x 3 root other 512 2004년 1월 31일 vsh |
| - # scp .ssh/id_rsa.pub pascal@PubHome:.ssh/authorized_keys |
| - Enter password: // 패스워드 cobol 입력 |
| - # |
| - # finish |
| - success |
| - }}} |
| - |
| - > pass = <font color=red>opensshkeygenok</font> |
| - |
| - !! level 55 |
| - |
| - + 풀이 방법 |
| - # find 옵션 -perm , -nouser , -type |
| - # rediection 사용 파일 생성 |
| - |
| - - 실제 풀이 |
| - {{{ |
| - # find / -perm 20 -o -print > /tmp/write.txt |
| - # find / -nouser > /tmp/no_own.txt |
| - # find / -type f \( -perm -004000 -o -perm -002000 \) > /tmp/suid.txt |
| - # finish |
| - please wait while the program checks your answer. This may take several minutes. |
| - checking write.txt |
| - checking no_own.txt |
| - checking suid.txt |
| - Success. |
| - }}} |
| - |
| - > pass = <font color=red>permissioncheckok</font> |
| - |
| - !! level 56 |
| - |
| - + 풀이 방법 |
| - # |
| - |
| - - 실제 풀이 |
| - {{{ |
| - |
| - }}} |
| - |
| - > pass = <font color=red></font> |
