view tests/test-amend.t @ 36755:ff4bc0ab6740 stable

wireproto: check permissions when executing "batch" command (BC) (SEC)

For as long as the "batch" command has existed (introduced by
bd88561afb4b and first released as part of Mercurial 1.9), that command
(like most wire commands introduced after 2008) lacked an entry in
the hgweb permissions table. And since we don't verify permissions if
an entry is missing from the permissions table, this meant that
executing a command via "batch" would bypass all permissions
checks.

The security implications are significant: a Mercurial HTTP server
would allow writes via "batch" wire protocol commands as long as
the HTTP request were processed by Mercurial and the process running
the Mercurial HTTP server had write access to the repository. The
Mercurial defaults of servers being read-only and the various web.*
config options to define access control were bypassed.

In addition, "batch" could be used to exfiltrate data from servers
that were configured to not allow read access.

Both forms of permissions bypass could be mitigated to some extent
by using HTTP authentication. This would prevent HTTP requests from
hitting Mercurial's server logic. However, any authenticated request
would still be able to bypass permissions checks via "batch" commands.

The easiest exploit was to send "pushkey" commands via "batch" and
modify the state of bookmarks, phases, and obsolescence markers.
However, I suspect a well-crafted HTTP request could trick the server
into running the "unbundle" wire protocol command, effectively
performing a full `hg push` to create new changesets on the remote.

This commit plugs this gaping security hole by having the "batch"
command perform permissions checking on each sub-command that is
being batched. We do this by threading a permissions checking
callable all the way to the protocol handler. The threading is a
bit hacky from a code perspective. But it preserves API compatibility,
which is the proper thing to do on the stable branch.

One of the subtle things we do is assume that a command with an
undefined permission is a "push" command. This is the safest thing to
do from a security perspective: we don't want to take chances that
a command could perform a write even though the server is configured
to not allow writes.

As the test changes demonstrate, it is no longer possible to bypass
permissions via the "batch" wire protocol command.

.. bc::

   The "batch" wire protocol command now enforces permissions of
   each invoked sub-command. Wire protocol commands must define
   their operation type or the "batch" command will assume they
   can write data and will prevent their execution on HTTP servers
   unless the HTTP request method is POST, the server is configured
   to allow pushes, and the (possibly authenticated) HTTP user is
   authorized to perform a push.

#testcases obsstore-off obsstore-on

  $ cat << EOF >> $HGRCPATH
  > [extensions]
  > amend=
  > debugdrawdag=$TESTDIR/drawdag.py
  > [diff]
  > git=1
  > EOF

#if obsstore-on
  $ cat << EOF >> $HGRCPATH
  > [experimental]
  > evolution.createmarkers=True
  > EOF
#endif

Basic amend

  $ hg init repo1
  $ cd repo1
  $ hg debugdrawdag <<'EOS'
  > B
  > |
  > A
  > EOS

  $ hg update B -q
  $ echo 2 >> B

  $ hg amend
  saved backup bundle to $TESTTMP/repo1/.hg/strip-backup/112478962961-7e959a55-amend.hg (obsstore-off !)
#if obsstore-off
  $ hg log -p -G --hidden -T '{rev} {node|short} {desc}\n'
  @  1 be169c7e8dbe B
  |  diff --git a/B b/B
  |  new file mode 100644
  |  --- /dev/null
  |  +++ b/B
  |  @@ -0,0 +1,1 @@
  |  +B2
  |
  o  0 426bada5c675 A
     diff --git a/A b/A
     new file mode 100644
     --- /dev/null
     +++ b/A
     @@ -0,0 +1,1 @@
     +A
     \ No newline at end of file
  
#else
  $ hg log -p -G --hidden -T '{rev} {node|short} {desc}\n'
  @  2 be169c7e8dbe B
  |  diff --git a/B b/B
  |  new file mode 100644
  |  --- /dev/null
  |  +++ b/B
  |  @@ -0,0 +1,1 @@
  |  +B2
  |
  | x  1 112478962961 B
  |/   diff --git a/B b/B
  |    new file mode 100644
  |    --- /dev/null
  |    +++ b/B
  |    @@ -0,0 +1,1 @@
  |    +B
  |    \ No newline at end of file
  |
  o  0 426bada5c675 A
     diff --git a/A b/A
     new file mode 100644
     --- /dev/null
     +++ b/A
     @@ -0,0 +1,1 @@
     +A
     \ No newline at end of file
  
#endif

Nothing changed

  $ hg amend
  nothing changed
  [1]

  $ hg amend -d "0 0"
  nothing changed
  [1]

  $ hg amend -d "Thu Jan 01 00:00:00 1970 UTC"
  nothing changed
  [1]

Matcher and metadata options

  $ echo 3 > C
  $ echo 4 > D
  $ hg add C D
  $ hg amend -m NEWMESSAGE -I C
  saved backup bundle to $TESTTMP/repo1/.hg/strip-backup/be169c7e8dbe-7684ddc5-amend.hg (obsstore-off !)
  $ hg log -r . -T '{node|short} {desc} {files}\n'
  c7ba14d9075b NEWMESSAGE B C
  $ echo 5 > E
  $ rm C
  $ hg amend -d '2000 1000' -u 'Foo <[e-mail]>' -A C D
  saved backup bundle to $TESTTMP/repo1/.hg/strip-backup/c7ba14d9075b-b3e76daa-amend.hg (obsstore-off !)
  $ hg log -r . -T '{node|short} {desc} {files} {author} {date}\n'
  14f6c4bcc865 NEWMESSAGE B D Foo <[e-mail]> 2000.01000

Amend with editor

  $ cat > $TESTTMP/prefix.sh <<'EOF'
  > printf 'EDITED: ' > $TESTTMP/msg
  > cat "$1" >> $TESTTMP/msg
  > mv $TESTTMP/msg "$1"
  > EOF
  $ chmod +x $TESTTMP/prefix.sh

  $ HGEDITOR="sh $TESTTMP/prefix.sh" hg amend --edit
  saved backup bundle to $TESTTMP/repo1/.hg/strip-backup/14f6c4bcc865-6591f15d-amend.hg (obsstore-off !)
  $ hg log -r . -T '{node|short} {desc}\n'
  298f085230c3 EDITED: NEWMESSAGE
  $ HGEDITOR="sh $TESTTMP/prefix.sh" hg amend -e -m MSG
  saved backup bundle to $TESTTMP/repo1/.hg/strip-backup/298f085230c3-d81a6ad3-amend.hg (obsstore-off !)
  $ hg log -r . -T '{node|short} {desc}\n'
  974f07f28537 EDITED: MSG

  $ echo FOO > $TESTTMP/msg
  $ hg amend -l $TESTTMP/msg -m BAR
  abort: options --message and --logfile are mutually exclusive
  [255]
  $ hg amend -l $TESTTMP/msg
  saved backup bundle to $TESTTMP/repo1/.hg/strip-backup/974f07f28537-edb6470a-amend.hg (obsstore-off !)
  $ hg log -r . -T '{node|short} {desc}\n'
  507be9bdac71 FOO

Interactive mode

  $ touch F G
  $ hg add F G
  $ cat <<EOS | hg amend -i --config ui.interactive=1
  > y
  > n
  > EOS
  diff --git a/F b/F
  new file mode 100644
  examine changes to 'F'? [Ynesfdaq?] y
  
  diff --git a/G b/G
  new file mode 100644
  examine changes to 'G'? [Ynesfdaq?] n
  
  saved backup bundle to $TESTTMP/repo1/.hg/strip-backup/507be9bdac71-c8077452-amend.hg (obsstore-off !)
  $ hg log -r . -T '{files}\n'
  B D F

Amend in the middle of a stack

  $ hg init $TESTTMP/repo2
  $ cd $TESTTMP/repo2
  $ hg debugdrawdag <<'EOS'
  > C
  > |
  > B
  > |
  > A
  > EOS

  $ hg update -q B
  $ echo 2 >> B
  $ hg amend
  abort: cannot amend changeset with children
  [255]

#if obsstore-on

With allowunstable, amend could work in the middle of a stack

  $ cat >> $HGRCPATH <<EOF
  > [experimental]
  > evolution.createmarkers=True
  > evolution.allowunstable=True
  > EOF

  $ hg amend
  1 new orphan changesets
  $ hg log -T '{rev} {node|short} {desc}\n' -G
  @  3 be169c7e8dbe B
  |
  | *  2 26805aba1e60 C
  | |
  | x  1 112478962961 B
  |/
  o  0 426bada5c675 A
  
Checking the note stored in the obsmarker

  $ echo foo > bar
  $ hg add bar
  $ hg amend --note 'yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy'
  abort: cannot store a note of more than 255 bytes
  [255]
  $ hg amend --note "adding bar"
  $ hg debugobsolete -r .
  112478962961147124edd43549aedd1a335e44bf be169c7e8dbe21cd10b3d79691cbe7f241e3c21c 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '8', 'operation': 'amend', 'user': 'test'}
  be169c7e8dbe21cd10b3d79691cbe7f241e3c21c 16084da537dd8f84cfdb3055c633772269d62e1b 0 (Thu Jan 01 00:00:00 1970 +0000) {'ef1': '8', 'note': 'adding bar', 'operation': 'amend', 'user': 'test'}
#endif

Cannot amend public changeset

  $ hg phase -r A --public
  $ hg update -C -q A
  $ hg amend -m AMEND
  abort: cannot amend public changesets
  (see 'hg help phases' for details)
  [255]

Amend a merge changeset

  $ hg init $TESTTMP/repo3
  $ cd $TESTTMP/repo3
  $ hg debugdrawdag <<'EOS'
  >   C
  >  /|
  > A B
  > EOS
  $ hg update -q C
  $ hg amend -m FOO
  saved backup bundle to $TESTTMP/repo3/.hg/strip-backup/a35c07e8a2a4-15ff4612-amend.hg (obsstore-off !)
  $ rm .hg/localtags
  $ hg log -G -T '{desc}\n'
  @    FOO
  |\
  | o  B
  |
  o  A
  

More complete test for status changes (issue5732)
-------------------------------------------------

Generates history of files having 3 states, r0_r1_wc:

 r0: ground (content/missing)
 r1: old state to be amended (content/missing, where missing means removed)
 wc: changes to be included in r1 (content/missing-tracked/untracked)

  $ hg init $TESTTMP/wcstates
  $ cd $TESTTMP/wcstates

  $ $PYTHON $TESTDIR/generate-working-copy-states.py state 2 1
  $ hg addremove -q --similarity 0
  $ hg commit -m0

  $ $PYTHON $TESTDIR/generate-working-copy-states.py state 2 2
  $ hg addremove -q --similarity 0
  $ hg commit -m1

  $ $PYTHON $TESTDIR/generate-working-copy-states.py state 2 wc
  $ hg addremove -q --similarity 0
  $ hg forget *_*_*-untracked
  $ rm *_*_missing-*

amend r1 to include wc changes

  $ hg amend
  saved backup bundle to * (glob) (obsstore-off !)

clean/modified/removed/added states of the amended revision

  $ hg status --all --change . 'glob:content1_*_content1-tracked'
  C content1_content1_content1-tracked
  C content1_content2_content1-tracked
  C content1_missing_content1-tracked
  $ hg status --all --change . 'glob:content1_*_content[23]-tracked'
  M content1_content1_content3-tracked
  M content1_content2_content2-tracked
  M content1_content2_content3-tracked
  M content1_missing_content3-tracked
  $ hg status --all --change . 'glob:content1_*_missing-tracked'
  M content1_content2_missing-tracked
  R content1_missing_missing-tracked
  C content1_content1_missing-tracked
  $ hg status --all --change . 'glob:content1_*_*-untracked'
  R content1_content1_content1-untracked
  R content1_content1_content3-untracked
  R content1_content1_missing-untracked
  R content1_content2_content1-untracked
  R content1_content2_content2-untracked
  R content1_content2_content3-untracked
  R content1_content2_missing-untracked
  R content1_missing_content1-untracked
  R content1_missing_content3-untracked
  R content1_missing_missing-untracked
  $ hg status --all --change . 'glob:missing_content2_*'
  A missing_content2_content2-tracked
  A missing_content2_content3-tracked
  A missing_content2_missing-tracked
  $ hg status --all --change . 'glob:missing_missing_*'
  A missing_missing_content3-tracked

working directory should be all clean (with some missing/untracked files)

  $ hg status --all 'glob:*_content?-tracked'
  C content1_content1_content1-tracked
  C content1_content1_content3-tracked
  C content1_content2_content1-tracked
  C content1_content2_content2-tracked
  C content1_content2_content3-tracked
  C content1_missing_content1-tracked
  C content1_missing_content3-tracked
  C missing_content2_content2-tracked
  C missing_content2_content3-tracked
  C missing_missing_content3-tracked
  $ hg status --all 'glob:*_missing-tracked'
  ! content1_content1_missing-tracked
  ! content1_content2_missing-tracked
  ! content1_missing_missing-tracked
  ! missing_content2_missing-tracked
  ! missing_missing_missing-tracked
  $ hg status --all 'glob:*-untracked'
  ? content1_content1_content1-untracked
  ? content1_content1_content3-untracked
  ? content1_content2_content1-untracked
  ? content1_content2_content2-untracked
  ? content1_content2_content3-untracked
  ? content1_missing_content1-untracked
  ? content1_missing_content3-untracked
  ? missing_content2_content2-untracked
  ? missing_content2_content3-untracked
  ? missing_missing_content3-untracked