diff options
author | David Woodhouse <David.Woodhouse@intel.com> | 2010-12-15 13:47:46 +0000 |
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committer | David Woodhouse <David.Woodhouse@intel.com> | 2010-12-15 13:47:46 +0000 |
commit | 74935b987fd0312f535747fea636883ae22fec77 (patch) | |
tree | 1860bee3f904244601d52f72db0e412f6584100e /doc/doc-docbook | |
parent | fb08281fe4730834c1265012d3cdeb558a671811 (diff) |
Allow only Exim or CONFIGURE_OWNER to use whitelisted configs with -C
We only added TRUSTED_CONFIG_PREFIX_FILE to compensate for the enforcing
of ALT_CONFIG_ROOT_ONLY. Let's not open it up any further than we need to;
other users don't get to make use of it.
Diffstat (limited to 'doc/doc-docbook')
-rw-r--r-- | doc/doc-docbook/spec.xfpt | 32 |
1 files changed, 17 insertions, 15 deletions
diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt index b2c40e48a..c9b77b88c 100644 --- a/doc/doc-docbook/spec.xfpt +++ b/doc/doc-docbook/spec.xfpt @@ -3336,7 +3336,8 @@ from the compiled-in list, Exim gives up its root privilege immediately, and runs with the real and effective uid and gid set to those of the caller. However, if a TRUSTED_CONFIG_PREFIX_LIST file is defined in &_Local/Makefile_&, root privilege is retained for any configuration file which matches a prefix -listed in that file. +listed in that file as long as the caller is the Exim user (or the user +specified in the CONFIGURE_OWNER option, if any). Leaving TRUSTED_CONFIG_PREFIX_LIST unset precludes the possibility of testing a configuration using &%-C%& right through message reception and delivery, @@ -4536,10 +4537,12 @@ A one-off alternate configuration can be specified by the &%-C%& command line option, which may specify a single file or a list of files. However, when &%-C%& is used, Exim gives up its root privilege, unless called by root (or unless the argument for &%-C%& is identical to the built-in value from -CONFIGURE_FILE) or matches a prefix listed in the TRUSTED_CONFIG_PREFIX_LIST -file. &%-C%& is useful mainly for checking the syntax of configuration files -before installing them. No owner or group checks are done on a configuration -file specified by &%-C%&, if root privilege has been dropped. +CONFIGURE_FILE), or matches a prefix listed in the TRUSTED_CONFIG_PREFIX_LIST +file and the caller is the Exim user or the user specified in the +CONFIGURE_OWNER setting. &%-C%& is useful mainly for checking the syntax of +configuration files before installing them. No owner or group checks are done +on a configuration file specified by &%-C%&, if root privilege has been +dropped. Even the Exim user is not trusted to specify an arbitrary configuration file with the &%-C%& option to be used with root privileges, unless that file is @@ -33820,17 +33823,16 @@ which only root has access, this guards against someone who has broken into the Exim account from running a privileged Exim with an arbitrary configuration file, and using it to break into other accounts. .next -If a non-trusted configuration file (i.e. the default configuration file or -one which is trusted by virtue of matching a prefix listed in the +If a non-trusted configuration file (i.e. not the default configuration file +or one which is trusted by virtue of matching a prefix listed in the TRUSTED_CONFIG_PREFIX_LIST file) is specified with &%-C%&, or if macros are -given with &%-D%& (but see the next item), -then root privilege is retained only if the caller of Exim -is root. This locks out the possibility of testing a configuration using &%-C%& -right through message reception and delivery, even if the caller is root. The -reception works, but by that time, Exim is running as the Exim user, so when -it re-execs to regain privilege for the delivery, the use of &%-C%& causes -privilege to be lost. However, root can test reception and delivery using two -separate commands. +given with &%-D%& (but see the next item), then root privilege is retained only +if the caller of Exim is root. This locks out the possibility of testing a +configuration using &%-C%& right through message reception and delivery, even +if the caller is root. The reception works, but by that time, Exim is running +as the Exim user, so when it re-execs to regain privilege for the delivery, the +use of &%-C%& causes privilege to be lost. However, root can test reception and +delivery using two separate commands. .next The WHITELIST_D_MACROS build option declares some macros to be safe to override with &%-D%& if the real uid is one of root, the Exim run-time user or the |