diff --git a/README.md b/README.md index 2b86064..e0aca39 100644 --- a/README.md +++ b/README.md @@ -30,6 +30,7 @@ Hardening applied: - Require a password for sudo every time it's called - Disable passwordless sudo for rpm-ostree - Setting more restrictive file permissions (Based on recommendations from [lynis](https://cisofy.com/lynis/)) +- Brute force protection by locking user accounts for 24 hours after 50 failed login attempts, hardened password encryption and password quality suggestions - Installing dnf-automatic and chkrootkit - Disabling unprivileged user namespaces - Replacing bubblewrap with bubblewrap-suid so flatpak can be used without unprivileged user namespaces diff --git a/config/common/common-scripts.yml b/config/common/common-scripts.yml index 0f2b326..ad1b152 100644 --- a/config/common/common-scripts.yml +++ b/config/common/common-scripts.yml @@ -1,4 +1,5 @@ type: script scripts: + - authselect.sh # this sets up the proper policy & signing files for signed images to work - signing.sh \ No newline at end of file diff --git a/config/files/usr/etc/login.defs b/config/files/usr/etc/login.defs new file mode 100644 index 0000000..1131d63 --- /dev/null +++ b/config/files/usr/etc/login.defs @@ -0,0 +1,610 @@ +# +# Please note that the parameters in this configuration file control the +# behavior of the tools from the shadow-utils component. None of these +# tools uses the PAM mechanism, and the utilities that use PAM (such as the +# passwd command) should therefore be configured elsewhere. Refer to +# /etc/pam.d/system-auth for more information. +# + +# +# Delay in seconds before being allowed another attempt after a login failure +# Note: When PAM is used, some modules may enforce a minimum delay (e.g. +# pam_unix(8) enforces a 2s delay) +# +#FAIL_DELAY 3 + +# Currently FAILLOG_ENAB is not supported + +# +# Enable display of unknown usernames when login(1) failures are recorded. +# +#LOG_UNKFAIL_ENAB no + +# Currently LOG_OK_LOGINS is not supported + +# Currently LASTLOG_ENAB is not supported + +# +# Limit the highest user ID number for which the lastlog entries should +# be updated. +# +# No LASTLOG_UID_MAX means that there is no user ID limit for writing +# lastlog entries. +# +#LASTLOG_UID_MAX + +# Currently MAIL_CHECK_ENAB is not supported + +# Currently OBSCURE_CHECKS_ENAB is not supported + +# Currently PORTTIME_CHECKS_ENAB is not supported + +# Currently QUOTAS_ENAB is not supported + +# Currently SYSLOG_SU_ENAB is not supported + +# +# Enable "syslog" logging of newgrp(1) and sg(1) activity. +# +#SYSLOG_SG_ENAB yes + +# Currently CONSOLE is not supported + +# Currently SULOG_FILE is not supported + +# Currently MOTD_FILE is not supported + +# Currently ISSUE_FILE is not supported + +# Currently TTYTYPE_FILE is not supported + +# Currently FTMP_FILE is not supported + +# Currently NOLOGINS_FILE is not supported + +# Currently SU_NAME is not supported + +# *REQUIRED* +# Directory where mailboxes reside, _or_ name of file, relative to the +# home directory. If you _do_ define both, MAIL_DIR takes precedence. +# +MAIL_DIR /var/spool/mail +#MAIL_FILE .mail + +# +# If defined, file which inhibits all the usual chatter during the login +# sequence. If a full pathname, then hushed mode will be enabled if the +# user's name or shell are found in the file. If not a full pathname, then +# hushed mode will be enabled if the file exists in the user's home directory. +# +#HUSHLOGIN_FILE .hushlogin +#HUSHLOGIN_FILE /etc/hushlogins + +# Currently ENV_TZ is not supported + +# Currently ENV_HZ is not supported + +# +# The default PATH settings, for superuser and normal users. +# +# (they are minimal, add the rest in the shell startup files) +#ENV_SUPATH PATH=/sbin:/bin:/usr/sbin:/usr/bin +#ENV_PATH PATH=/bin:/usr/bin + +# +# Terminal permissions +# +# TTYGROUP Login tty will be assigned this group ownership. +# TTYPERM Login tty will be set to this permission. +# +# If you have a write(1) program which is "setgid" to a special group +# which owns the terminals, define TTYGROUP as the number of such group +# and TTYPERM as 0620. Otherwise leave TTYGROUP commented out and +# set TTYPERM to either 622 or 600. +# +#TTYGROUP tty +#TTYPERM 0600 + +# Currently ERASECHAR, KILLCHAR and ULIMIT are not supported + +# Default initial "umask" value used by login(1) on non-PAM enabled systems. +# Default "umask" value for pam_umask(8) on PAM enabled systems. +# UMASK is also used by useradd(8) and newusers(8) to set the mode for new +# home directories if HOME_MODE is not set. +# 022 is the default value, but 027, or even 077, could be considered +# for increased privacy. There is no One True Answer here: each sysadmin +# must make up their mind. +UMASK 027 + +# HOME_MODE is used by useradd(8) and newusers(8) to set the mode for new +# home directories. +# If HOME_MODE is not set, the value of UMASK is used to create the mode. +HOME_MODE 0700 + +# Password aging controls: +# +# PASS_MAX_DAYS Maximum number of days a password may be used. +# PASS_MIN_DAYS Minimum number of days allowed between password changes. +# PASS_MIN_LEN Minimum acceptable password length. +# PASS_WARN_AGE Number of days warning given before a password expires. +# +PASS_MAX_DAYS 99999 +PASS_MIN_DAYS 0 +PASS_WARN_AGE 7 + +# Currently PASS_MIN_LEN is not supported + +# Currently SU_WHEEL_ONLY is not supported + +# Currently CRACKLIB_DICTPATH is not supported + +# +# Min/max values for automatic uid selection in useradd(8) +# +UID_MIN 1000 +UID_MAX 60000 +# System accounts +SYS_UID_MIN 201 +SYS_UID_MAX 999 +# Extra per user uids +SUB_UID_MIN 524288 +SUB_UID_MAX 600100000 +SUB_UID_COUNT 65536 + +# +# Min/max values for automatic gid selection in groupadd(8) +# +GID_MIN 1000 +GID_MAX 60000 +# System accounts +SYS_GID_MIN 201 +SYS_GID_MAX 999 +# Extra per user group ids +SUB_GID_MIN 524288 +SUB_GID_MAX 600100000 +SUB_GID_COUNT 65536 + +# +# Max number of login(1) retries if password is bad +# +#LOGIN_RETRIES 3 + +# +# Max time in seconds for login(1) +# +#LOGIN_TIMEOUT 60 + +# Currently PASS_CHANGE_TRIES is not supported + +# Currently PASS_ALWAYS_WARN is not supported + +# Currently PASS_MAX_LEN is not supported + +# Currently CHFN_AUTH is not supported + +# +# Which fields may be changed by regular users using chfn(1) - use +# any combination of letters "frwh" (full name, room number, work +# phone, home phone). If not defined, no changes are allowed. +# For backward compatibility, "yes" = "rwh" and "no" = "frwh". +# +#CHFN_RESTRICT rwh + +# Currently LOGIN_STRING is not supported + +# Currently MD5_CRYPT_ENAB is not supported + +# +# If set to MD5, MD5-based algorithm will be used for encrypting password +# If set to SHA256, SHA256-based algorithm will be used for encrypting password +# If set to SHA512, SHA512-based algorithm will be used for encrypting password +# If set to BCRYPT, BCRYPT-based algorithm will be used for encrypting password +# If set to YESCRYPT, YESCRYPT-based algorithm will be used for encrypting password +# If set to DES, DES-based algorithm will be used for encrypting password (default) +# +ENCRYPT_METHOD YESCRYPT + +# +# Only works if ENCRYPT_METHOD is set to SHA256 or SHA512. +# +# Define the number of SHA rounds. +# With a lot of rounds, it is more difficult to brute-force the password. +# However, more CPU resources will be needed to authenticate users if +# this value is increased. +# +# If not specified, the libc will choose the default number of rounds (5000). +# The values must be within the 1000-999999999 range. +# +#SHA_CRYPT_MAX_ROUNDS 5000 + +# Currently SHA_CRYPT_MIN_ROUNDS is not supported + +# +# Only works if ENCRYPT_METHOD is set to BCRYPT. +# +# Define the number of BCRYPT rounds. +# With a lot of rounds, it is more difficult to brute-force the password. +# However, more CPU resources will be needed to authenticate users if +# this value is increased. +# +# If not specified, 13 rounds will be attempted. +# If only one of the MIN or MAX values is set, then this value will be used. +# If MIN > MAX, the highest value will be used. +# +#BCRYPT_MIN_ROUNDS 13 +#BCRYPT_MAX_ROUNDS 31 + +# +# Only works if ENCRYPT_METHOD is set to YESCRYPT. +# +# Define the YESCRYPT cost factor. +# With a higher cost factor, it is more difficult to brute-force the password. +# However, more CPU time and more memory will be needed to authenticate users +# if this value is increased. +# +# If not specified, a cost factor of# +# Please note that the parameters in this configuration file control the +# behavior of the tools from the shadow-utils component. None of these +# tools uses the PAM mechanism, and the utilities that use PAM (such as the +# passwd command) should therefore be configured elsewhere. Refer to +# /etc/pam.d/system-auth for more information. +# + +# +# Delay in seconds before being allowed another attempt after a login failure +# Note: When PAM is used, some modules may enforce a minimum delay (e.g. +# pam_unix(8) enforces a 2s delay) +# +#FAIL_DELAY 3 + +# Currently FAILLOG_ENAB is not supported + +# +# Enable display of unknown usernames when login(1) failures are recorded. +# +#LOG_UNKFAIL_ENAB no + +# Currently LOG_OK_LOGINS is not supported + +# Currently LASTLOG_ENAB is not supported + +# +# Limit the highest user ID number for which the lastlog entries should +# be updated. +# +# No LASTLOG_UID_MAX means that there is no user ID limit for writing +# lastlog entries. +# +#LASTLOG_UID_MAX + +# Currently MAIL_CHECK_ENAB is not supported + +# Currently OBSCURE_CHECKS_ENAB is not supported + +# Currently PORTTIME_CHECKS_ENAB is not supported + +# Currently QUOTAS_ENAB is not supported + +# Currently SYSLOG_SU_ENAB is not supported + +# +# Enable "syslog" logging of newgrp(1) and sg(1) activity. +# +#SYSLOG_SG_ENAB yes + +# Currently CONSOLE is not supported + +# Currently SULOG_FILE is not supported + +# Currently MOTD_FILE is not supported + +# Currently ISSUE_FILE is not supported + +# Currently TTYTYPE_FILE is not supported + +# Currently FTMP_FILE is not supported + +# Currently NOLOGINS_FILE is not supported + +# Currently SU_NAME is not supported + +# *REQUIRED* +# Directory where mailboxes reside, _or_ name of file, relative to the +# home directory. If you _do_ define both, MAIL_DIR takes precedence. +# +MAIL_DIR /var/spool/mail +#MAIL_FILE .mail + +# +# If defined, file which inhibits all the usual chatter during the login +# sequence. If a full pathname, then hushed mode will be enabled if the +# user's name or shell are found in the file. If not a full pathname, then +# hushed mode will be enabled if the file exists in the user's home directory. +# +#HUSHLOGIN_FILE .hushlogin +#HUSHLOGIN_FILE /etc/hushlogins + +# Currently ENV_TZ is not supported + +# Currently ENV_HZ is not supported + +# +# The default PATH settings, for superuser and normal users. +# +# (they are minimal, add the rest in the shell startup files) +#ENV_SUPATH PATH=/sbin:/bin:/usr/sbin:/usr/bin +#ENV_PATH PATH=/bin:/usr/bin + +# +# Terminal permissions +# +# TTYGROUP Login tty will be assigned this group ownership. +# TTYPERM Login tty will be set to this permission. +# +# If you have a write(1) program which is "setgid" to a special group +# which owns the terminals, define TTYGROUP as the number of such group +# and TTYPERM as 0620. Otherwise leave TTYGROUP commented out and +# set TTYPERM to either 622 or 600. +# +#TTYGROUP tty +#TTYPERM 0600 + +# Currently ERASECHAR, KILLCHAR and ULIMIT are not supported + +# Default initial "umask" value used by login(1) on non-PAM enabled systems. +# Default "umask" value for pam_umask(8) on PAM enabled systems. +# UMASK is also used by useradd(8) and newusers(8) to set the mode for new +# home directories if HOME_MODE is not set. +# 022 is the default value, but 027, or even 077, could be considered +# for increased privacy. There is no One True Answer here: each sysadmin +# must make up their mind. +UMASK 022 + +# HOME_MODE is used by useradd(8) and newusers(8) to set the mode for new +# home directories. +# If HOME_MODE is not set, the value of UMASK is used to create the mode. +HOME_MODE 0700 + +# Password aging controls: +# +# PASS_MAX_DAYS Maximum number of days a password may be used. +# PASS_MIN_DAYS Minimum number of days allowed between password changes. +# PASS_MIN_LEN Minimum acceptable password length. +# PASS_WARN_AGE Number of days warning given before a password expires. +# +PASS_MAX_DAYS 99999 +PASS_MIN_DAYS 0 +PASS_WARN_AGE 7 + +# Currently PASS_MIN_LEN is not supported + +# Currently SU_WHEEL_ONLY is not supported + +# Currently CRACKLIB_DICTPATH is not supported + +# +# Min/max values for automatic uid selection in useradd(8) +# +UID_MIN 1000 +UID_MAX 60000 +# System accounts +SYS_UID_MIN 201 +SYS_UID_MAX 999 +# Extra per user uids +SUB_UID_MIN 524288 +SUB_UID_MAX 600100000 +SUB_UID_COUNT 65536 + +# +# Min/max values for automatic gid selection in groupadd(8) +# +GID_MIN 1000 +GID_MAX 60000 +# System accounts +SYS_GID_MIN 201 +SYS_GID_MAX 999 +# Extra per user group ids +SUB_GID_MIN 524288 +SUB_GID_MAX 600100000 +SUB_GID_COUNT 65536 + +# +# Max number of login(1) retries if password is bad +# +#LOGIN_RETRIES 3 + +# +# Max time in seconds for login(1) +# +#LOGIN_TIMEOUT 60 + +# Currently PASS_CHANGE_TRIES is not supported + +# Currently PASS_ALWAYS_WARN is not supported + +# Currently PASS_MAX_LEN is not supported + +# Currently CHFN_AUTH is not supported + +# +# Which fields may be changed by regular users using chfn(1) - use +# any combination of letters "frwh" (full name, room number, work +# phone, home phone). If not defined, no changes are allowed. +# For backward compatibility, "yes" = "rwh" and "no" = "frwh". +# +#CHFN_RESTRICT rwh + +# Currently LOGIN_STRING is not supported + +# Currently MD5_CRYPT_ENAB is not supported + +# +# If set to MD5, MD5-based algorithm will be used for encrypting password +# If set to SHA256, SHA256-based algorithm will be used for encrypting password +# If set to SHA512, SHA512-based algorithm will be used for encrypting password +# If set to BCRYPT, BCRYPT-based algorithm will be used for encrypting password +# If set to YESCRYPT, YESCRYPT-based algorithm will be used for encrypting password +# If set to DES, DES-based algorithm will be used for encrypting password (default) +# +ENCRYPT_METHOD YESCRYPT + +# +# Only works if ENCRYPT_METHOD is set to SHA256 or SHA512. +# +# Define the number of SHA rounds. +# With a lot of rounds, it is more difficult to brute-force the password. +# However, more CPU resources will be needed to authenticate users if +# this value is increased. +# +# If not specified, the libc will choose the default number of rounds (5000). +# The values must be within the 1000-999999999 range. +# +#SHA_CRYPT_MAX_ROUNDS 5000 + +# Currently SHA_CRYPT_MIN_ROUNDS is not supported + +# +# Only works if ENCRYPT_METHOD is set to BCRYPT. +# +# Define the number of BCRYPT rounds. +# With a lot of rounds, it is more difficult to brute-force the password. +# However, more CPU resources will be needed to authenticate users if +# this value is increased. +# +# If not specified, 13 rounds will be attempted. +# If only one of the MIN or MAX values is set, then this value will be used. +# If MIN > MAX, the highest value will be used. +# +#BCRYPT_MIN_ROUNDS 13 +#BCRYPT_MAX_ROUNDS 31 + +# +# Only works if ENCRYPT_METHOD is set to YESCRYPT. +# +# Define the YESCRYPT cost factor. +# With a higher cost factor, it is more difficult to brute-force the password. +# However, more CPU time and more memory will be needed to authenticate users +# if this value is increased. +# +# If not specified, a cost factor of 5 will be used. +# The value must be within the 1-11 range. +# +YESCRYPT_COST_FACTOR 11 + +# Currently CONSOLE_GROUPS is not supported + +# +# Should login be allowed if we can't cd to the home directory? +# Default is yes. +# +#DEFAULT_HOME yes + +# Currently ENVIRON_FILE is not supported + +# +# If defined, this command is run when removing a user. +# It should remove any at/cron/print jobs etc. owned by +# the user to be removed (passed as the first argument). +# +#USERDEL_CMD /usr/sbin/userdel_local + +# +# Enables userdel(8) to remove user groups if no members exist. +# +USERGROUPS_ENAB yes + +# +# If set to a non-zero number, the shadow utilities will make sure that +# groups never have more than this number of users on one line. +# This permits to support split groups (groups split into multiple lines, +# with the same group ID, to avoid limitation of the line length in the +# group file). +# +# 0 is the default value and disables this feature. +# +#MAX_MEMBERS_PER_GROUP 0 + +# +# If useradd(8) should create home directories for users by default (non +# system users only). +# This option is overridden with the -M or -m flags on the useradd(8) +# command-line. +# +CREATE_HOME yes + +# +# Force use shadow, even if shadow passwd & shadow group files are +# missing. +# +#FORCE_SHADOW yes + +# +# Select the HMAC cryptography algorithm. +# Used in pam_timestamp module to calculate the keyed-hash message +# authentication code. +# +# Note: It is recommended to check hmac(3) to see the possible algorithms +# that are available in your system. +# +HMAC_CRYPTO_ALGO SHA512 + 5 will be used. +# The value must be within the 1-11 range. +# +YESCRYPT_COST_FACTOR 11 + +# Currently CONSOLE_GROUPS is not supported + +# +# Should login be allowed if we can't cd to the home directory? +# Default is yes. +# +#DEFAULT_HOME yes + +# Currently ENVIRON_FILE is not supported + +# +# If defined, this command is run when removing a user. +# It should remove any at/cron/print jobs etc. owned by +# the user to be removed (passed as the first argument). +# +#USERDEL_CMD /usr/sbin/userdel_local + +# +# Enables userdel(8) to remove user groups if no members exist. +# +USERGROUPS_ENAB yes + +# +# If set to a non-zero number, the shadow utilities will make sure that +# groups never have more than this number of users on one line. +# This permits to support split groups (groups split into multiple lines, +# with the same group ID, to avoid limitation of the line length in the +# group file). +# +# 0 is the default value and disables this feature. +# +#MAX_MEMBERS_PER_GROUP 0 + +# +# If useradd(8) should create home directories for users by default (non +# system users only). +# This option is overridden with the -M or -m flags on the useradd(8) +# command-line. +# +CREATE_HOME yes + +# +# Force use shadow, even if shadow passwd & shadow group files are +# missing. +# +#FORCE_SHADOW yes + +# +# Select the HMAC cryptography algorithm. +# Used in pam_timestamp module to calculate the keyed-hash message +# authentication code. +# +# Note: It is recommended to check hmac(3) to see the possible algorithms +# that are available in your system. +# +HMAC_CRYPTO_ALGO SHA512 diff --git a/config/files/usr/etc/security/faillock.conf b/config/files/usr/etc/security/faillock.conf new file mode 100644 index 0000000..f964e83 --- /dev/null +++ b/config/files/usr/etc/security/faillock.conf @@ -0,0 +1,62 @@ +# Configuration for locking the user after multiple failed +# authentication attempts. +# +# The directory where the user files with the failure records are kept. +# The default is /var/run/faillock. +# dir = /var/run/faillock +# +# Will log the user name into the system log if the user is not found. +# Enabled if option is present. +audit +# +# Don't print informative messages. +# Enabled if option is present. +# silent +# +# Don't log informative messages via syslog. +# Enabled if option is present. +# no_log_info +# +# Only track failed user authentications attempts for local users +# in /etc/passwd and ignore centralized (AD, IdM, LDAP, etc.) users. +# The `faillock` command will also no longer track user failed +# authentication attempts. Enabling this option will prevent a +# double-lockout scenario where a user is locked out locally and +# in the centralized mechanism. +# Enabled if option is present. +# local_users_only +# +# Deny access if the number of consecutive authentication failures +# for this user during the recent interval exceeds n tries. +# The default is 3. +deny = 50 +# +# The length of the interval during which the consecutive +# authentication failures must happen for the user account +# lock out is n seconds. +# The default is 900 (15 minutes). +# fail_interval = 900 +# +# The access will be re-enabled after n seconds after the lock out. +# The value 0 has the same meaning as value `never` - the access +# will not be re-enabled without resetting the faillock +# entries by the `faillock` command. +# The default is 600 (10 minutes). +unlock_time = 86400 +# +# Root account can become locked as well as regular accounts. +# Enabled if option is present. +even_deny_root +# +# This option implies the `even_deny_root` option. +# Allow access after n seconds to root account after the +# account is locked. In case the option is not specified +# the value is the same as of the `unlock_time` option. +# root_unlock_time = 900 +# +# If a group name is specified with this option, members +# of the group will be handled by this module the same as +# the root account (the options `even_deny_root>` and +# `root_unlock_time` will apply to them. +# By default, the option is not set. +# admin_group = diff --git a/config/files/usr/etc/security/pwquality.conf b/config/files/usr/etc/security/pwquality.conf new file mode 100644 index 0000000..f2f6b81 --- /dev/null +++ b/config/files/usr/etc/security/pwquality.conf @@ -0,0 +1,79 @@ +# Configuration for systemwide password quality limits +# Defaults: +# +# Number of characters in the new password that must not be present in the +# old password. +# difok = 1 +# +# Minimum acceptable size for the new password (plus one if +# credits are not disabled which is the default). (See pam_cracklib manual.) +# Cannot be set to lower value than 6. +minlen = 15 +# +# The maximum credit for having digits in the new password. If less than 0 +# it is the minimum number of digits in the new password. +dcredit = -1 +# +# The maximum credit for having uppercase characters in the new password. +# If less than 0 it is the minimum number of uppercase characters in the new +# password. +ucredit = -1 +# +# The maximum credit for having lowercase characters in the new password. +# If less than 0 it is the minimum number of lowercase characters in the new +# password. +lcredit = -1 +# +# The maximum credit for having other characters in the new password. +# If less than 0 it is the minimum number of other characters in the new +# password. +ocredit = -1 +# +# The minimum number of required classes of characters for the new +# password (digits, uppercase, lowercase, others). +# minclass = 0 +# +# The maximum number of allowed consecutive same characters in the new password. +# The check is disabled if the value is 0. +# maxrepeat = 0 +# +# The maximum number of allowed consecutive characters of the same class in the +# new password. +# The check is disabled if the value is 0. +# maxclassrepeat = 0 +# +# Whether to check for the words from the passwd entry GECOS string of the user. +# The check is enabled if the value is not 0. +# gecoscheck = 0 +# +# Whether to check for the words from the cracklib dictionary. +# The check is enabled if the value is not 0. +dictcheck = 1 +# +# Whether to check if it contains the user name in some form. +# The check is enabled if the value is not 0. +usercheck = 1 +# +# Length of substrings from the username to check for in the password +# The check is enabled if the value is greater than 0 and usercheck is enabled. +usersubstr = 5 +# +# Whether the check is enforced by the PAM module and possibly other +# applications. +# The new password is rejected if it fails the check and the value is not 0. +enforcing = 0 +# +# Path to the cracklib dictionaries. Default is to use the cracklib default. +# dictpath = +# +# Prompt user at most N times before returning with error. The default is 1. +# retry = 3 +# +# Enforces pwquality checks on the root user password. +# Enabled if the option is present. +enforce_for_root +# +# Skip testing the password quality for users that are not present in the +# /etc/passwd file. +# Enabled if the option is present. +# local_users_only diff --git a/config/scripts/authselect.sh b/config/scripts/authselect.sh new file mode 100644 index 0000000..c4bde28 --- /dev/null +++ b/config/scripts/authselect.sh @@ -0,0 +1,6 @@ +#!/usr/bin/env bash +set -e + +echo "Enabling faillock in PAM authentication profile" + +authselect enable-feature with-faillock 1> /dev/null \ No newline at end of file