tests: add low-level SSH protocol tests
We don't really have good low-level tests for the behavior of the SSH
wire protocol. This commit attempts to establish some.
The added tests consist of a mixture of starting a server
with `hg serve --stdio` and sending bytes to it and using
`hg debugpeer` to go through the official client code. Having
insight into what raw bytes are exchanged as well as what the peer
does is useful.
We also introduce a test extension for modifying the behavior of
the SSH server and peer. For example, we change the server to
not recognize the "hello" command, simulating behavior of <0.9.1
servers.
These tests are generally useful to have. But the impetus for creating
them now is they will be needed for verifying behavior of old clients
and servers when a new SSH protocol is introduced.
Differential Revision: https://phab.mercurial-scm.org/D2026
# no-check-commit because of serve_forever()
$ cat >> $HGRCPATH << EOF
> [ui]
> ssh = $PYTHON "$TESTDIR/dummyssh"
> [devel]
> debug.peer-request = true
> [extensions]
> sshprotoext = $TESTDIR/sshprotoext.py
> EOF
$ hg init server
$ cd server
$ echo 0 > foo
$ hg -q add foo
$ hg commit -m initial
$ cd ..
Test a normal behaving server, for sanity
$ hg --debug debugpeer ssh://user@dummy/server
running * "*/tests/dummyssh" 'user@dummy' 'hg -R server serve --stdio' (glob)
devel-peer-request: hello
sending hello command
devel-peer-request: between
devel-peer-request: pairs: 81 bytes
sending between command
remote: 384
remote: capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
remote: 1
url: ssh://user@dummy/server
local: no
pushable: yes
Server should answer the "hello" command in isolation
$ hg -R server serve --stdio << EOF
> hello
> EOF
384
capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
>=0.9.1 clients send a "hello" + "between" for the null range as part of handshake.
Server should reply with capabilities and should send "1\n\n" as a successful
reply with empty response to the "between".
$ hg -R server serve --stdio << EOF
> hello
> between
> pairs 81
> 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
> EOF
384
capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
1
SSH banner is not printed by default, ignored by clients
$ SSHSERVERMODE=banner hg debugpeer ssh://user@dummy/server
url: ssh://user@dummy/server
local: no
pushable: yes
--debug will print the banner
$ SSHSERVERMODE=banner hg --debug debugpeer ssh://user@dummy/server
running * "*/tests/dummyssh" 'user@dummy' 'hg -R server serve --stdio' (glob)
devel-peer-request: hello
sending hello command
devel-peer-request: between
devel-peer-request: pairs: 81 bytes
sending between command
remote: banner: line 0
remote: banner: line 1
remote: banner: line 2
remote: banner: line 3
remote: banner: line 4
remote: banner: line 5
remote: banner: line 6
remote: banner: line 7
remote: banner: line 8
remote: banner: line 9
remote: 384
remote: capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
remote: 1
url: ssh://user@dummy/server
local: no
pushable: yes
And test the banner with the raw protocol
$ SSHSERVERMODE=banner hg -R server serve --stdio << EOF
> hello
> between
> pairs 81
> 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
> EOF
banner: line 0
banner: line 1
banner: line 2
banner: line 3
banner: line 4
banner: line 5
banner: line 6
banner: line 7
banner: line 8
banner: line 9
384
capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
1
Connecting to a <0.9.1 server that doesn't support the hello command
$ SSHSERVERMODE=no-hello hg --debug debugpeer ssh://user@dummy/server
running * "*/tests/dummyssh" 'user@dummy' 'hg -R server serve --stdio' (glob)
devel-peer-request: hello
sending hello command
devel-peer-request: between
devel-peer-request: pairs: 81 bytes
sending between command
remote: 0
remote: 1
url: ssh://user@dummy/server
local: no
pushable: yes
The client should interpret this as no capabilities
$ SSHSERVERMODE=no-hello hg debugcapabilities ssh://user@dummy/server
Main capabilities:
Sending an unknown command to the server results in an empty response to that command
$ hg -R server serve --stdio << EOF
> pre-hello
> hello
> between
> pairs 81
> 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
> EOF
0
384
capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
1
$ hg --config sshpeer.mode=extra-handshake-commands --config sshpeer.handshake-mode=pre-no-args --debug debugpeer ssh://user@dummy/server
running * "*/tests/dummyssh" 'user@dummy' 'hg -R server serve --stdio' (glob)
devel-peer-request: no-args
sending no-args command
devel-peer-request: hello
sending hello command
devel-peer-request: between
devel-peer-request: pairs: 81 bytes
sending between command
remote: 0
remote: 384
remote: capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
remote: 1
url: ssh://user@dummy/server
local: no
pushable: yes
Send multiple unknown commands before hello
$ hg -R server serve --stdio << EOF
> unknown1
> unknown2
> unknown3
> hello
> between
> pairs 81
> 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
> EOF
0
0
0
384
capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
1
$ hg --config sshpeer.mode=extra-handshake-commands --config sshpeer.handshake-mode=pre-multiple-no-args --debug debugpeer ssh://user@dummy/server
running * "*/tests/dummyssh" 'user@dummy' 'hg -R server serve --stdio' (glob)
devel-peer-request: unknown1
sending unknown1 command
devel-peer-request: unknown2
sending unknown2 command
devel-peer-request: unknown3
sending unknown3 command
devel-peer-request: hello
sending hello command
devel-peer-request: between
devel-peer-request: pairs: 81 bytes
sending between command
remote: 0
remote: 0
remote: 0
remote: 384
remote: capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
remote: 1
url: ssh://user@dummy/server
local: no
pushable: yes
Send an unknown command before hello that has arguments
$ hg -R server serve --stdio << EOF
> with-args
> foo 13
> value for foo
> bar 13
> value for bar
> hello
> between
> pairs 81
> 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
> EOF
0
0
0
0
0
384
capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
1
Send an unknown command having an argument that looks numeric
$ hg -R server serve --stdio << EOF
> unknown
> foo 1
> 0
> hello
> between
> pairs 81
> 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
> EOF
0
0
0
384
capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
1
$ hg -R server serve --stdio << EOF
> unknown
> foo 1
> 1
> hello
> between
> pairs 81
> 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
> EOF
0
0
0
384
capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
1
When sending a dict argument value, it is serialized to
"<arg> <item count>" followed by "<key> <len>\n<value>" for each item
in the dict.
Dictionary value for unknown command
$ hg -R server serve --stdio << EOF
> unknown
> dict 3
> key1 3
> foo
> key2 3
> bar
> key3 3
> baz
> hello
> EOF
0
0
0
0
0
0
0
0
384
capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
Incomplete dictionary send
$ hg -R server serve --stdio << EOF
> unknown
> dict 3
> key1 3
> foo
> EOF
0
0
0
0
Incomplete value send
$ hg -R server serve --stdio << EOF
> unknown
> dict 3
> key1 3
> fo
> EOF
0
0
0
0
Send a command line with spaces
$ hg -R server serve --stdio << EOF
> unknown withspace
> hello
> between
> pairs 81
> 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
> EOF
0
384
capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
1
$ hg -R server serve --stdio << EOF
> unknown with multiple spaces
> hello
> between
> pairs 81
> 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
> EOF
0
384
capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
1
$ hg -R server serve --stdio << EOF
> unknown with spaces
> key 10
> some value
> hello
> between
> pairs 81
> 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000
> EOF
0
0
0
384
capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
1
Send an unknown command after the "between"
$ hg -R server serve --stdio << EOF
> hello
> between
> pairs 81
> 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000unknown
> EOF
384
capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
1
0
And one with arguments
$ hg -R server serve --stdio << EOF
> hello
> between
> pairs 81
> 0000000000000000000000000000000000000000-0000000000000000000000000000000000000000unknown
> foo 5
> value
> bar 3
> baz
> EOF
384
capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
1
0
0
0
0
0