From a319333493ad1839ff7fb1d4b6f43dc719b57844 Mon Sep 17 00:00:00 2001 From: madaidan <50278627+madaidan@users.noreply.github.com> Date: Sun, 30 Jun 2019 13:09:51 +0000 Subject: [PATCH 1/7] Create login.defs --- etc/login.defs | 337 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 337 insertions(+) create mode 100644 etc/login.defs diff --git a/etc/login.defs b/etc/login.defs new file mode 100644 index 0000000..072727c --- /dev/null +++ b/etc/login.defs @@ -0,0 +1,337 @@ +# +# /etc/login.defs - Configuration control definitions for the login package. +# +# Three items must be defined: MAIL_DIR, ENV_SUPATH, and ENV_PATH. +# If unspecified, some arbitrary (and possibly incorrect) value will +# be assumed. All other items are optional - if not specified then +# the described action or option will be inhibited. +# +# Comment lines (lines beginning with "#") and blank lines are ignored. +# +# Modified for Linux. --marekm + +# REQUIRED for useradd/userdel/usermod +# Directory where mailboxes reside, _or_ name of file, relative to the +# home directory. If you _do_ define MAIL_DIR and MAIL_FILE, +# MAIL_DIR takes precedence. +# +# Essentially: +# - MAIL_DIR defines the location of users mail spool files +# (for mbox use) by appending the username to MAIL_DIR as defined +# below. +# - MAIL_FILE defines the location of the users mail spool files as the +# fully-qualified filename obtained by prepending the user home +# directory before $MAIL_FILE +# +# NOTE: This is no more used for setting up users MAIL environment variable +# which is, starting from shadow 4.0.12-1 in Debian, entirely the +# job of the pam_mail PAM modules +# See default PAM configuration files provided for +# login, su, etc. +# +# This is a temporary situation: setting these variables will soon +# move to /etc/default/useradd and the variables will then be +# no more supported +MAIL_DIR /var/mail +#MAIL_FILE .mail + +# +# Enable logging and display of /var/log/faillog login failure info. +# This option conflicts with the pam_tally PAM module. +# +FAILLOG_ENAB yes + +# +# Enable display of unknown usernames when login failures are recorded. +# +# WARNING: Unknown usernames may become world readable. +# See #290803 and #298773 for details about how this could become a security +# concern +LOG_UNKFAIL_ENAB no + +# +# Enable logging of successful logins +# +LOG_OK_LOGINS no + +# +# Enable "syslog" logging of su activity - in addition to sulog file logging. +# SYSLOG_SG_ENAB does the same for newgrp and sg. +# +SYSLOG_SU_ENAB yes +SYSLOG_SG_ENAB yes + +# +# If defined, all su activity is logged to this file. +# +#SULOG_FILE /var/log/sulog + +# +# If defined, file which maps tty line to TERM environment parameter. +# Each line of the file is in a format something like "vt100 tty01". +# +#TTYTYPE_FILE /etc/ttytype + +# +# If defined, login failures will be logged here in a utmp format +# last, when invoked as lastb, will read /var/log/btmp, so... +# +FTMP_FILE /var/log/btmp + +# +# If defined, the command name to display when running "su -". For +# example, if this is defined as "su" then a "ps" will display the +# command is "-su". If not defined, then "ps" would display the +# name of the shell actually being run, e.g. something like "-sh". +# +SU_NAME su + +# +# 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 + +# +# *REQUIRED* The default PATH settings, for superuser and normal users. +# +# (they are minimal, add the rest in the shell startup files) +ENV_SUPATH PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin +ENV_PATH PATH=/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games + +# +# 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" program which is "setgid" to a special group +# which owns the terminals, define TTYGROUP to the group number and +# TTYPERM to 0620. Otherwise leave TTYGROUP commented out and assign +# TTYPERM to either 622 or 600. +# +# In Debian /usr/bin/bsd-write or similar programs are setgid tty +# However, the default and recommended value for TTYPERM is still 0600 +# to not allow anyone to write to anyone else console or terminal + +# Users can still allow other people to write them by issuing +# the "mesg y" command. + +TTYGROUP tty +TTYPERM 0600 + +# +# Login configuration initializations: +# +# ERASECHAR Terminal ERASE character ('\010' = backspace). +# KILLCHAR Terminal KILL character ('\025' = CTRL/U). +# UMASK Default "umask" value. +# +# The ERASECHAR and KILLCHAR are used only on System V machines. +# +# UMASK is the default umask value for pam_umask and is used by +# useradd and newusers to set the mode of the new home directories. +# 022 is the "historical" value in Debian for UMASK +# 027, or even 077, could be considered better for privacy +# There is no One True Answer here : each sysadmin must make up his/her +# mind. +# +# If USERGROUPS_ENAB is set to "yes", that will modify this UMASK default value +# for private user groups, i. e. the uid is the same as gid, and username is +# the same as the primary group name: for these, the user permissions will be +# used as group permissions, e. g. 022 will become 002. +# +# Prefix these values with "0" to get octal, "0x" to get hexadecimal. +# +ERASECHAR 0177 +KILLCHAR 025 +UMASK 022 + +# +# 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_WARN_AGE Number of days warning given before a password expires. +# +PASS_MAX_DAYS 99999 +PASS_MIN_DAYS 0 +PASS_WARN_AGE 7 + +# +# Min/max values for automatic uid selection in useradd +# +UID_MIN 1000 +UID_MAX 60000 +# System accounts +#SYS_UID_MIN 100 +#SYS_UID_MAX 999 + +# +# Min/max values for automatic gid selection in groupadd +# +GID_MIN 1000 +GID_MAX 60000 +# System accounts +#SYS_GID_MIN 100 +#SYS_GID_MAX 999 + +# +# Max number of login retries if password is bad. This will most likely be +# overriden by PAM, since the default pam_unix module has it's own built +# in of 3 retries. However, this is a safe fallback in case you are using +# an authentication module that does not enforce PAM_MAXTRIES. +# +LOGIN_RETRIES 5 + +# +# Max time in seconds for login +# +LOGIN_TIMEOUT 60 + +# +# Which fields may be changed by regular users using chfn - 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 + +# +# Should login be allowed if we can't cd to the home directory? +# Default in no. +# +DEFAULT_HOME yes + +# +# 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 + +# +# If set to yes, userdel will remove the user's group if it contains no +# more members, and useradd will create by default a group with the name +# of the user. +# +# Other former uses of this variable such as setting the umask when +# user==primary group are not used in PAM environments, such as Debian +# +USERGROUPS_ENAB yes + +# +# Instead of the real user shell, the program specified by this parameter +# will be launched, although its visible name (argv[0]) will be the shell's. +# The program may do whatever it wants (logging, additional authentification, +# banner, ...) before running the actual shell. +# +# FAKE_SHELL /bin/fakeshell + +# +# If defined, either full pathname of a file containing device names or +# a ":" delimited list of device names. Root logins will be allowed only +# upon these devices. +# +# This variable is used by login and su. +# +#CONSOLE /etc/consoles +#CONSOLE console:tty01:tty02:tty03:tty04 + +# +# List of groups to add to the user's supplementary group set +# when logging in on the console (as determined by the CONSOLE +# setting). Default is none. +# +# Use with caution - it is possible for users to gain permanent +# access to these groups, even when not logged in on the console. +# How to do it is left as an exercise for the reader... +# +# This variable is used by login and su. +# +#CONSOLE_GROUPS floppy:audio:cdrom + +# +# If set to "yes", new passwords will be encrypted using the MD5-based +# algorithm compatible with the one used by recent releases of FreeBSD. +# It supports passwords of unlimited length and longer salt strings. +# Set to "no" if you need to copy encrypted passwords to other systems +# which don't understand the new algorithm. Default is "no". +# +# This variable is deprecated. You should use ENCRYPT_METHOD. +# +#MD5_CRYPT_ENAB no + +# +# 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 DES, DES-based algorithm will be used for encrypting password (default) +# Overrides the MD5_CRYPT_ENAB option +# +# Note: It is recommended to use a value consistent with +# the PAM modules configuration. +# +ENCRYPT_METHOD SHA512 + +# +# Only used 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 forcing the password. +# But note also that it more CPU resources will be needed to authenticate +# users. +# +# If not specified, the libc will choose the default number of rounds (5000). +# The values must be inside the 1000-999999999 range. +# 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. +# +# SHA_CRYPT_MIN_ROUNDS 5000 +# SHA_CRYPT_MAX_ROUNDS 5000 + +################# OBSOLETED BY PAM ############## +# # +# These options are now handled by PAM. Please # +# edit the appropriate file in /etc/pam.d/ to # +# enable the equivelants of them. +# +############### + +#MOTD_FILE +#DIALUPS_CHECK_ENAB +#LASTLOG_ENAB +#MAIL_CHECK_ENAB +#OBSCURE_CHECKS_ENAB +#PORTTIME_CHECKS_ENAB +#SU_WHEEL_ONLY +#CRACKLIB_DICTPATH +#PASS_CHANGE_TRIES +#PASS_ALWAYS_WARN +#ENVIRON_FILE +#NOLOGINS_FILE +#ISSUE_FILE +#PASS_MIN_LEN +#PASS_MAX_LEN +#ULIMIT +#ENV_HZ +#CHFN_AUTH +#CHSH_AUTH +#FAIL_DELAY + +################# OBSOLETED ####################### +# # +# These options are no more handled by shadow. # +# # +# Shadow utilities will display a warning if they # +# still appear. # +# # +################################################### + +# CLOSE_SESSIONS +# LOGIN_STRING +# NO_PASSWORD_CONSOLE +# QMAIL_DIR From 09a5c27f475ea6947180088b4efb615101fdbf9c Mon Sep 17 00:00:00 2001 From: madaidan <50278627+madaidan@users.noreply.github.com> Date: Sun, 30 Jun 2019 13:10:29 +0000 Subject: [PATCH 2/7] Create common-session --- etc/pam.d/common-session | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) create mode 100644 etc/pam.d/common-session diff --git a/etc/pam.d/common-session b/etc/pam.d/common-session new file mode 100644 index 0000000..9d7324c --- /dev/null +++ b/etc/pam.d/common-session @@ -0,0 +1,26 @@ +# +# /etc/pam.d/common-session - session-related modules common to all services +# +# This file is included from other service-specific PAM config files, +# and should contain a list of modules that define tasks to be performed +# at the start and end of sessions of *any* kind (both interactive and +# non-interactive). +# +# As of pam 1.0.1-6, this file is managed by pam-auth-update by default. +# To take advantage of this, it is recommended that you configure any +# local modules either before or after the default block, and use +# pam-auth-update to manage selection of other modules. See +# pam-auth-update(8) for details. + +# here are the per-package modules (the "Primary" block) +session [default=1] pam_permit.so +# here's the fallback if no module succeeds +session requisite pam_deny.so +# prime the stack with a positive return value if there isn't one already; +# this avoids us returning an error just because nothing sets a success code +# since the modules above will each just jump around +session required pam_permit.so +# and here are more per-package modules (the "Additional" block) +session required pam_unix.so +session optional pam_systemd.so +# end of pam-auth-update config From 501901f7c04514c66a4f97f5eb0e523aa55a1094 Mon Sep 17 00:00:00 2001 From: madaidan <50278627+madaidan@users.noreply.github.com> Date: Sun, 30 Jun 2019 13:10:54 +0000 Subject: [PATCH 3/7] Change default umask to 006 --- etc/login.defs | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/etc/login.defs b/etc/login.defs index 072727c..8a95443 100644 --- a/etc/login.defs +++ b/etc/login.defs @@ -148,7 +148,7 @@ TTYPERM 0600 # ERASECHAR 0177 KILLCHAR 025 -UMASK 022 +UMASK 006 # # Password aging controls: From 1e1d29cfdedaa01d0180b8ca5a79c6f401728432 Mon Sep 17 00:00:00 2001 From: madaidan <50278627+madaidan@users.noreply.github.com> Date: Sun, 30 Jun 2019 13:11:31 +0000 Subject: [PATCH 4/7] Create common-session-noninteractive --- etc/pam.d/common-session-noninteractive | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) create mode 100644 etc/pam.d/common-session-noninteractive diff --git a/etc/pam.d/common-session-noninteractive b/etc/pam.d/common-session-noninteractive new file mode 100644 index 0000000..c9144d5 --- /dev/null +++ b/etc/pam.d/common-session-noninteractive @@ -0,0 +1,25 @@ +# +# /etc/pam.d/common-session-noninteractive - session-related modules +# common to all non-interactive services +# +# This file is included from other service-specific PAM config files, +# and should contain a list of modules that define tasks to be performed +# at the start and end of all non-interactive sessions. +# +# As of pam 1.0.1-6, this file is managed by pam-auth-update by default. +# To take advantage of this, it is recommended that you configure any +# local modules either before or after the default block, and use +# pam-auth-update to manage selection of other modules. See +# pam-auth-update(8) for details. + +# here are the per-package modules (the "Primary" block) +session [default=1] pam_permit.so +# here's the fallback if no module succeeds +session requisite pam_deny.so +# prime the stack with a positive return value if there isn't one already; +# this avoids us returning an error just because nothing sets a success code +# since the modules above will each just jump around +session required pam_permit.so +# and here are more per-package modules (the "Additional" block) +session required pam_unix.so +# end of pam-auth-update config From a9af85f58529e0dcb154b669bd53aba8333d5634 Mon Sep 17 00:00:00 2001 From: madaidan <50278627+madaidan@users.noreply.github.com> Date: Sun, 30 Jun 2019 13:12:16 +0000 Subject: [PATCH 5/7] Update common-session --- etc/pam.d/common-session | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/etc/pam.d/common-session b/etc/pam.d/common-session index 9d7324c..3b3e948 100644 --- a/etc/pam.d/common-session +++ b/etc/pam.d/common-session @@ -22,5 +22,6 @@ session requisite pam_deny.so session required pam_permit.so # and here are more per-package modules (the "Additional" block) session required pam_unix.so -session optional pam_systemd.so +session optional pam_systemd.so +session optional pam_umask.so usergroups # end of pam-auth-update config From eedeaa0e7faf8d9f75d99d037fa80bd5d08c6db3 Mon Sep 17 00:00:00 2001 From: madaidan <50278627+madaidan@users.noreply.github.com> Date: Sun, 30 Jun 2019 13:12:59 +0000 Subject: [PATCH 6/7] Update common-session-noninteractive --- etc/pam.d/common-session-noninteractive | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/etc/pam.d/common-session-noninteractive b/etc/pam.d/common-session-noninteractive index c9144d5..699391f 100644 --- a/etc/pam.d/common-session-noninteractive +++ b/etc/pam.d/common-session-noninteractive @@ -21,5 +21,6 @@ session requisite pam_deny.so # since the modules above will each just jump around session required pam_permit.so # and here are more per-package modules (the "Additional" block) -session required pam_unix.so +session required pam_unix.so +session optional pam_umask.so usergroups # end of pam-auth-update config From cfaafe400cd1f77df12f7f6dc9c9da58595bcbdf Mon Sep 17 00:00:00 2001 From: madaidan <50278627+madaidan@users.noreply.github.com> Date: Sun, 30 Jun 2019 13:16:12 +0000 Subject: [PATCH 7/7] Update control --- debian/control | 3 +++ 1 file changed, 3 insertions(+) diff --git a/debian/control b/debian/control index ee7de76..e2afb3c 100644 --- a/debian/control +++ b/debian/control @@ -115,3 +115,6 @@ Description: enhances misc security settings . A systemd service mounts /proc with hidepid=2 at boot to prevent users from seeing each other's processes. + . + The default umask is changed to 006. This allows only the owner and group to read + and write to newly created files.