ssh: switch from libssh2 to libssh

Rewrite the implementation of the ssh block driver to use libssh instead
of libssh2.  The libssh library has various advantages over libssh2:
- easier API for authentication (for example for using ssh-agent)
- easier API for known_hosts handling
- supports newer types of keys in known_hosts

Use APIs/features available in libssh 0.8 conditionally, to support
older versions (which are not recommended though).

Adjust the iotest 207 according to the different error message, and to
find the default key type for localhost (to properly compare the
fingerprint with).
Contributed-by: Max Reitz <mreitz@redhat.com>

Adjust the various Docker/Travis scripts to use libssh when available
instead of libssh2. The mingw/mxe testing is dropped for now, as there
are no packages for it.

Signed-off-by: Pino Toscano <ptoscano@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20190620200840.17655-1-ptoscano@redhat.com
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 5873173.t2JhDm7DL7@lindworm.usersys.redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

7 files changed, 47 insertions, 19 deletions

diff --git a/tests/docker/dockerfiles/debian-win32-cross.docker b/tests/docker/dockerfiles/debian-win32-cross.docker
index dd021f2df0..0a4970c068 100644
--- a/tests/docker/dockerfiles/debian-win32-cross.docker
+++ b/tests/docker/dockerfiles/debian-win32-cross.docker
@@ -15,7 +15,6 @@ RUN DEBIAN_FRONTEND=noninteractive eatmydata \
         mxe-$TARGET-w64-mingw32.shared-curl \
         mxe-$TARGET-w64-mingw32.shared-glib \
         mxe-$TARGET-w64-mingw32.shared-libgcrypt \
-        mxe-$TARGET-w64-mingw32.shared-libssh2 \
         mxe-$TARGET-w64-mingw32.shared-libusb1 \
         mxe-$TARGET-w64-mingw32.shared-lzo \
         mxe-$TARGET-w64-mingw32.shared-nettle \
diff --git a/tests/docker/dockerfiles/debian-win64-cross.docker b/tests/docker/dockerfiles/debian-win64-cross.docker
index 4542bcc821..b27985b1b1 100644
--- a/tests/docker/dockerfiles/debian-win64-cross.docker
+++ b/tests/docker/dockerfiles/debian-win64-cross.docker
@@ -15,7 +15,6 @@ RUN DEBIAN_FRONTEND=noninteractive eatmydata \
         mxe-$TARGET-w64-mingw32.shared-curl \
         mxe-$TARGET-w64-mingw32.shared-glib \
         mxe-$TARGET-w64-mingw32.shared-libgcrypt \
-        mxe-$TARGET-w64-mingw32.shared-libssh2 \
         mxe-$TARGET-w64-mingw32.shared-libusb1 \
         mxe-$TARGET-w64-mingw32.shared-lzo \
         mxe-$TARGET-w64-mingw32.shared-nettle \
diff --git a/tests/docker/dockerfiles/fedora.docker b/tests/docker/dockerfiles/fedora.docker
index 12c460597e..619d1b5656 100644
--- a/tests/docker/dockerfiles/fedora.docker
+++ b/tests/docker/dockerfiles/fedora.docker
@@ -35,7 +35,7 @@ ENV PACKAGES \
     libpng-devel \
     librbd-devel \
     libseccomp-devel \
-    libssh2-devel \
+    libssh-devel \
     libubsan \
     libusbx-devel \
     libxml2-devel \
@@ -50,7 +50,6 @@ ENV PACKAGES \
     mingw32-gtk3 \
     mingw32-libjpeg-turbo \
     mingw32-libpng \
-    mingw32-libssh2 \
     mingw32-libtasn1 \
     mingw32-nettle \
     mingw32-pixman \
@@ -64,7 +63,6 @@ ENV PACKAGES \
     mingw64-gtk3 \
     mingw64-libjpeg-turbo \
     mingw64-libpng \
-    mingw64-libssh2 \
     mingw64-libtasn1 \
     mingw64-nettle \
     mingw64-pixman \
diff --git a/tests/docker/dockerfiles/ubuntu.docker b/tests/docker/dockerfiles/ubuntu.docker
index 8d256961f0..d3b72209c8 100644
--- a/tests/docker/dockerfiles/ubuntu.docker
+++ b/tests/docker/dockerfiles/ubuntu.docker
@@ -53,7 +53,7 @@ ENV PACKAGES flex bison \
     libsnappy-dev \
     libspice-protocol-dev \
     libspice-server-dev \
-    libssh2-1-dev \
+    libssh-dev \
     libusb-1.0-0-dev \
     libusbredirhost-dev \
     libvdeplug-dev \
diff --git a/tests/docker/dockerfiles/ubuntu1804.docker b/tests/docker/dockerfiles/ubuntu1804.docker
index 2e2900150b..9d80b11500 100644
--- a/tests/docker/dockerfiles/ubuntu1804.docker
+++ b/tests/docker/dockerfiles/ubuntu1804.docker
@@ -40,7 +40,7 @@ ENV PACKAGES flex bison \
     libsnappy-dev \
     libspice-protocol-dev \
     libspice-server-dev \
-    libssh2-1-dev \
+    libssh-dev \
     libusb-1.0-0-dev \
     libusbredirhost-dev \
     libvdeplug-dev \
diff --git a/tests/qemu-iotests/207 b/tests/qemu-iotests/207
index b3816136f7..ec8c1d06f0 100755
--- a/tests/qemu-iotests/207
+++ b/tests/qemu-iotests/207
@@ -110,12 +110,49 @@ with iotests.FilePath('t.img') as disk_path, \
 
     iotests.img_info_log(remote_path)
 
-    md5_key = subprocess.check_output(
-        'ssh-keyscan -t rsa 127.0.0.1 2>/dev/null | grep -v "\\^#" | ' +
-        'cut -d" " -f3 | base64 -d | md5sum -b | cut -d" " -f1',
-        shell=True).rstrip().decode('ascii')
+    keys = subprocess.check_output(
+        'ssh-keyscan 127.0.0.1 2>/dev/null | grep -v "\\^#" | ' +
+        'cut -d" " -f3',
+        shell=True).rstrip().decode('ascii').split('\n')
+
+    # Mappings of base64 representations to digests
+    md5_keys = {}
+    sha1_keys = {}
+
+    for key in keys:
+        md5_keys[key] = subprocess.check_output(
+            'echo %s | base64 -d | md5sum -b | cut -d" " -f1' % key,
+            shell=True).rstrip().decode('ascii')
+
+        sha1_keys[key] = subprocess.check_output(
+            'echo %s | base64 -d | sha1sum -b | cut -d" " -f1' % key,
+            shell=True).rstrip().decode('ascii')
 
     vm.launch()
+
+    # Find correct key first
+    matching_key = None
+    for key in keys:
+        result = vm.qmp('blockdev-add',
+                        driver='ssh', node_name='node0', path=disk_path,
+                        server={
+                             'host': '127.0.0.1',
+                             'port': '22',
+                        }, host_key_check={
+                             'mode': 'hash',
+                             'type': 'md5',
+                             'hash': md5_keys[key],
+                        })
+
+        if 'error' not in result:
+            vm.qmp('blockdev-del', node_name='node0')
+            matching_key = key
+            break
+
+    if matching_key is None:
+        vm.shutdown()
+        iotests.notrun('Did not find a key that fits 127.0.0.1')
+
     blockdev_create(vm, { 'driver': 'ssh',
                           'location': {
                               'path': disk_path,
@@ -140,7 +177,7 @@ with iotests.FilePath('t.img') as disk_path, \
                               'host-key-check': {
                                   'mode': 'hash',
                                   'type': 'md5',
-                                  'hash': md5_key,
+                                  'hash': md5_keys[matching_key],
                               }
                           },
                           'size': 8388608 })
@@ -148,11 +185,6 @@ with iotests.FilePath('t.img') as disk_path, \
 
     iotests.img_info_log(remote_path)
 
-    sha1_key = subprocess.check_output(
-        'ssh-keyscan -t rsa 127.0.0.1 2>/dev/null | grep -v "\\^#" | ' +
-        'cut -d" " -f3 | base64 -d | sha1sum -b | cut -d" " -f1',
-        shell=True).rstrip().decode('ascii')
-
     vm.launch()
     blockdev_create(vm, { 'driver': 'ssh',
                           'location': {
@@ -178,7 +210,7 @@ with iotests.FilePath('t.img') as disk_path, \
                               'host-key-check': {
                                   'mode': 'hash',
                                   'type': 'sha1',
-                                  'hash': sha1_key,
+                                  'hash': sha1_keys[matching_key],
                               }
                           },
                           'size': 4194304 })
diff --git a/tests/qemu-iotests/207.out b/tests/qemu-iotests/207.out
index ec9823793a..1239d9d648 100644
--- a/tests/qemu-iotests/207.out
+++ b/tests/qemu-iotests/207.out
@@ -68,7 +68,7 @@ virtual size: 4 MiB (4194304 bytes)
 
 {"execute": "blockdev-create", "arguments": {"job-id": "job0", "options": {"driver": "ssh", "location": {"host-key-check": {"mode": "none"}, "path": "/this/is/not/an/existing/path", "server": {"host": "127.0.0.1", "port": "22"}}, "size": 4194304}}}
 {"return": {}}
-Job failed: failed to open remote file '/this/is/not/an/existing/path': Failed opening remote file (libssh2 error code: -31)
+Job failed: failed to open remote file '/this/is/not/an/existing/path': SFTP server: No such file (libssh error code: 1, sftp error code: 2)
 {"execute": "job-dismiss", "arguments": {"id": "job0"}}
 {"return": {}}