Commit graph

11 commits

Author SHA1 Message Date
John Johansen
a2d56c3c74 parser: consolidate rule class handling into aa_class
Instead of having each rule individually handle the class info
introduce a class_rule_t into the hierarchy and consolidate.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2023-03-31 02:21:19 -07:00
John Johansen
d371458533 parser: make base classes for rules using prefixes and perms and use them
Cleanup the parse code by making shared prefix and perms classes for
rules and convert rules to use them.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2023-03-31 02:17:26 -07:00
John Johansen
fdf5b062a9 parser: fixup audit struct to audit enum
This removes the struct wrapper used in the previous patch to ensure
that all uses are properly converted.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2023-03-31 02:12:35 -07:00
John Johansen
7a318d99f2 parser: convert audit from bool to enum
Audit control support is going to be extended to support allowing
policy to which rules should quiet auditing. Update the frontend
internals to prepare for this.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2023-03-31 02:08:20 -07:00
John Johansen
134e95f783 parser: fixup remove struct from the audit bool conversion
This removes the struct wrapper used in the previous patch to ensure
that all uses are properly converted.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2023-03-31 01:08:25 -07:00
John Johansen
44f3be091a parser: convert the stored audit from a bit mask to a bool
This delays the convertion of the audit flag until passing to the
backend. This is a step towards fix the parser front end so that it
doesn't use encoded permission mappings.

Note: the patch embedds the bool conversion into a struct to ensure
the compiler will fail to build unless every use is fixed. The
struct is removed in the following patch.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2023-03-31 01:05:29 -07:00
John Johansen
fd9a6fe133 parser: int mode to perms
Move from using and int for permissions bit mask to a perms_t type.
Also move any perms mask that uses the name mode to perms to avoid
confusing it with other uses of mode.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2023-03-29 10:45:44 -07:00
Steve Beattie
461d9c2294
treewide: spelling/typo fixes in comments and docs
With the exception of the documentation fixes, these should all be
invisible to users.

Signed-off-by: Steve Beattie <steve.beattie@canonical.com>
Acked-by: Christian Boltz <apparmor@cboltz.de>
MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/687
2020-12-01 12:47:11 -08:00
Steve Beattie
35bbe528d2 parser: fix more gcc 5 compilation problems
Don't pass an ostream reference into another ostream via <<.

Signed-off-by: Steve Beattie <steve@nxnw.org>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2015-02-26 14:55:13 -08:00
Steve Beattie
019de74059 parser: fix logic error and incorrect reference from previous commit
Signed-off-by: Steve Beattie <steve@nxnw.org>
Acked-by: John Johansen <john.johansen@canonical.com>
2014-09-03 13:34:10 -07:00
John Johansen
dd44858e60 parser: first step implementing fine grained mediation for unix domain sockets
This patch implements parsing of fine grained mediation for unix domain
sockets, that have abstract and anonymous paths. Sockets with file
system paths are handled by regular file access rules.

The unix network rules follow the general fine grained network
rule pattern of

  [<qualifiers>] af_name [<access expr>] [<rule conds>] [<local expr>] [<peer expr>]

specifically for af_unix this is

  [<qualifiers>] 'unix' [<access expr>] [<rule conds>] [<local expr>] [<peer expr>]

  <qualifiers> = [ 'audit' ] [ 'allow' | 'deny' ]

  <access expr> = ( <access> | <access list> )

  <access> = ( 'server' | 'create' | 'bind' | 'listen' | 'accept' |
               'connect' | 'shutdown' | 'getattr' | 'setattr' |
	       'getopt' | 'setopt' |
               'send' | 'receive' | 'r' | 'w' | 'rw' )
  (some access modes are incompatible with some rules or require additional
   parameters)

  <access list> = '(' <access> ( [','] <WS> <access> )* ')'

  <WS> = white space

  <rule conds> = ( <type cond> | <protocol cond> )*
     each cond can appear at most once

  <type cond> = 'type' '='  ( <AARE> | '(' ( '"' <AARE> '"' | <AARE> )+ ')' )

  <protocol cond> = 'protocol' '='  ( <AARE> | '(' ( '"' <AARE> '"' | <AARE> )+ ')' )

  <local expr> = ( <path cond> | <attr cond> | <opt cond> )*
     each cond can appear at most once

  <peer expr> = 'peer' '=' ( <path cond> | <label cond> )+
     each cond can appear at most once

  <path cond> = 'path' '=' ( <AARE> | '(' '"' <AARE> '"' | <AARE> ')' )

  <label cond> = 'label' '=' ( <AARE> | '(' '"' <AARE> '"' | <AARE> ')')

  <attr cond> = 'attr' '=' ( <AARE> | '(' '"' <AARE> '"' | <AARE> ')' )

  <opt cond> = 'opt' '=' ( <AARE> | '(' '"' <AARE> '"' | <AARE> ')' )

  <AARE> = ?*[]{}^ ( see man page )

 unix domain socket rules are accumulated so that the granted unix
 socket permissions are the union of all the listed unix rule permissions.

 unix domain socket rules are broad and general and become more restrictive
 as further information is specified. Policy may be specified down to
 the path and label level. The content of the communication is not
 examined.

 Some permissions are not compatible with all unix rules.

 unix socket rule permissions are implied when a rule does not explicitly
 state an access list. By default if a rule does not have an access list
 all permissions that are compatible with the specified set of local
 and peer conditionals are implied.

 The 'server', 'r', 'w' and 'rw' permissions are aliases for other permissions.
 server = (create, bind, listen, accept)
 r = (receive, getattr, getopt)
 w = (create, connect, send, setattr, setopt)

In addition it supports the v7 kernel abi semantics around generic
network rules. The v7 abi removes the masking unix and netlink
address families from the generic masking and uses fine grained
mediation for an address type if supplied.

This means that the rules

  network unix,
  network netlink,

are now enforced instead of ignored. The parser previously could accept
these but the kernel would ignore anything written to them. If a network
rule is supplied it takes precedence over the finer grained mediation
rule. If permission is not granted via a broad network access rule
fine grained mediation is applied.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
2014-09-03 13:22:26 -07:00