dispatch: protect against malicious 'hg serve --stdio' invocations (sec)
Some shared-ssh installations assume that 'hg serve --stdio' is a safe
command to run for minimally trusted users. Unfortunately, the messy
implementation of argument parsing here meant that trying to access a
repo named '--debugger' would give the user a pdb prompt, thereby
sidestepping any hoped-for sandboxing. Serving repositories over HTTP(S)
is unaffected.
We're not currently hardening any subcommands other than 'serve'. If
your service exposes other commands to users with arbitrary repository
names, it is imperative that you defend against repository names of
'--debugger' and anything starting with '--config'.
The read-only mode of hg-ssh stopped working because it provided its hook
configuration to "hg serve --stdio" via --config parameter. This is banned for
security reasons now. This patch switches it to directly call ui.setconfig().
If your custom hosting infrastructure relies on passing --config to
"hg serve --stdio", you'll need to find a different way to get that configuration
into Mercurial, either by using ui.setconfig() as hg-ssh does in this patch,
or by placing an hgrc file someplace where Mercurial will read it.
mitrandir@fb.com provided some extra fixes for the dispatch code and
for hg-ssh in places that I overlooked.
$ hg init
audit of .hg
$ hg add .hg/00changelog.i
abort: path contains illegal component: .hg/00changelog.i (glob)
[255]
#if symlink
Symlinks
$ mkdir a
$ echo a > a/a
$ hg ci -Ama
adding a/a
$ ln -s a b
$ echo b > a/b
$ hg add b/b
abort: path 'b/b' traverses symbolic link 'b' (glob)
[255]
$ hg add b
should still fail - maybe
$ hg add b/b
abort: path 'b/b' traverses symbolic link 'b' (glob)
[255]
$ hg commit -m 'add symlink b'
Test symlink traversing when accessing history:
-----------------------------------------------
(build a changeset where the path exists as a directory)
$ hg up 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ mkdir b
$ echo c > b/a
$ hg add b/a
$ hg ci -m 'add directory b'
created new head
Test that hg cat does not do anything wrong the working copy has 'b' as directory
$ hg cat b/a
c
$ hg cat -r "desc(directory)" b/a
c
$ hg cat -r "desc(symlink)" b/a
b/a: no such file in rev bc151a1f53bd
[1]
Test that hg cat does not do anything wrong the working copy has 'b' as a symlink (issue4749)
$ hg up 'desc(symlink)'
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg cat b/a
b/a: no such file in rev bc151a1f53bd
[1]
$ hg cat -r "desc(directory)" b/a
c
$ hg cat -r "desc(symlink)" b/a
b/a: no such file in rev bc151a1f53bd
[1]
#endif
unbundle tampered bundle
$ hg init target
$ cd target
$ hg unbundle "$TESTDIR/bundles/tampered.hg"
adding changesets
adding manifests
adding file changes
added 5 changesets with 6 changes to 6 files (+4 heads)
(run 'hg heads' to see heads, 'hg merge' to merge)
attack .hg/test
$ hg manifest -r0
.hg/test
$ hg update -Cr0
abort: path contains illegal component: .hg/test (glob)
[255]
attack foo/.hg/test
$ hg manifest -r1
foo/.hg/test
$ hg update -Cr1
abort: path 'foo/.hg/test' is inside nested repo 'foo' (glob)
[255]
attack back/test where back symlinks to ..
$ hg manifest -r2
back
back/test
#if symlink
$ hg update -Cr2
abort: path 'back/test' traverses symbolic link 'back'
[255]
#else
('back' will be a file and cause some other system specific error)
$ hg update -Cr2
abort: * (glob)
[255]
#endif
attack ../test
$ hg manifest -r3
../test
$ hg update -Cr3
abort: path contains illegal component: ../test (glob)
[255]
attack /tmp/test
$ hg manifest -r4
/tmp/test
$ hg update -Cr4
abort: path contains illegal component: /tmp/test (glob)
[255]
$ cd ..