platform_system_sepolicy/seapp_contexts
William Roberts 81e1f90cd1 check_seapp: add support for "neverallow" checks
Introduce "neverallow" rules for seapp_contexts. A neverallow rule is
similar to the existing key-value-pair entries but the line begins
with "neverallow". A neverallow violation is detected when all keys,
both inputs and outputs are matched. The neverallow rules value
parameter (not the key) can contain regular expressions to assist in
matching. Neverallow rules are never output to the generated
seapp_contexts file.

Also, unless -o is specified, checkseapp runs in silent mode and
outputs nothing. Specifying - as an argument to -o outputs to stdout.

Sample Output:
Error: Rule in File "external/sepolicy/seapp_contexts" on line 87: "user=fake domain=system_app type=app_data_file" violates neverallow in File "external/sepolicy/seapp_contexts" on line 57: "user=((?!system).)* domain=system_app"

Change-Id: Ia4dcbf02feb774f2e201bb0c5d4ce385274d8b8d
Signed-off-by: William Roberts <william.c.roberts@intel.com>
2015-06-25 23:53:46 +00:00

86 lines
3.7 KiB
Text

# Input selectors:
# isSystemServer (boolean)
# isOwner (boolean)
# user (string)
# seinfo (string)
# name (string)
# path (string)
# isSystemServer=true can only be used once.
# An unspecified isSystemServer defaults to false.
# isOwner=true will only match for the owner/primary user.
# isOwner=false will only match for secondary users.
# If unspecified, the entry can match either case.
# An unspecified string selector will match any value.
# A user string selector that ends in * will perform a prefix match.
# user=_app will match any regular app UID.
# user=_isolated will match any isolated service UID.
# All specified input selectors in an entry must match (i.e. logical AND).
# Matching is case-insensitive.
#
# Precedence rules:
# (1) isSystemServer=true before isSystemServer=false.
# (2) Specified isOwner= before unspecified isOwner= boolean.
# (3) Specified user= string before unspecified user= string.
# (4) Fixed user= string before user= prefix (i.e. ending in *).
# (5) Longer user= prefix before shorter user= prefix.
# (6) Specified seinfo= string before unspecified seinfo= string.
# (7) Specified name= string before unspecified name= string.
# (8) Specified path= string before unspecified path= string.
#
# Outputs:
# domain (string)
# type (string)
# levelFrom (string; one of none, all, app, or user)
# level (string)
# Only entries that specify domain= will be used for app process labeling.
# Only entries that specify type= will be used for app directory labeling.
# levelFrom=user is only supported for _app or _isolated UIDs.
# levelFrom=app or levelFrom=all is only supported for _app UIDs.
# level may be used to specify a fixed level for any UID.
#
#
# Neverallow Assertions
# Additional compile time assertion checks can be added as well. The assertion
# rules are lines beginning with the keyword neverallow. Full support for PCRE
# regular expressions exists on all input and output selectors. Neverallow
# rules are never output to the built seapp_contexts file. Like all keywords,
# neverallows are case-insensitive. A neverallow is asserted when all key value
# inputs are matched on a key value rule line.
#
# only the system server can be in system_server domain
neverallow isSystemServer=false domain=system_server
neverallow isSystemServer="" domain=system_server
# system domains should never be assigned outside of system uid
neverallow user=((?!system).)* domain=system_app
neverallow user=((?!system).)* type=system_app_data_file
# anything with a non-known uid with a specified name should have a specified seinfo
neverallow user=_app name=.* seinfo=""
neverallow user=_app name=.* seinfo=default
# neverallow shared relro to any other domain
# and neverallow any other uid into shared_relro
neverallow user=shared_relro domain=((?!shared_relro).)*
neverallow user=((?!shared_relro).)* domain=shared_relro
# neverallow non-isolated uids into isolated_app domain
# and vice versa
neverallow user=_isolated domain=((?!isolated_app).)*
neverallow user=((?!_isolated).)* domain=isolated_app
# uid shell should always be in shell domain, however non-shell
# uid's can be in shell domain
neverallow user=shell domain=((?!shell).)*
isSystemServer=true domain=system_server
user=system seinfo=platform domain=system_app type=system_app_data_file
user=bluetooth seinfo=platform domain=bluetooth type=bluetooth_data_file
user=nfc seinfo=platform domain=nfc type=nfc_data_file
user=radio seinfo=platform domain=radio type=radio_data_file
user=shared_relro domain=shared_relro
user=shell seinfo=platform domain=shell type=shell_data_file
user=_isolated domain=isolated_app levelFrom=user
user=_app seinfo=platform domain=platform_app type=app_data_file levelFrom=user
user=_app domain=untrusted_app type=app_data_file levelFrom=user