CVE-2021-44141: s3: torture: Add samba3.blackbox.test_symlink_traversal.SMB2.

Add to knownfail.d/symlink_traversal

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14911

Signed-off-by: Jeremy Allison <jra@samba.org>

3 files changed, 270 insertions, 0 deletions

diff --git a/selftest/knownfail.d/symlink_traversal b/selftest/knownfail.d/symlink_traversal
new file mode 100644
index 00000000000..a8ac4bbae1f
--- /dev/null
+++ b/selftest/knownfail.d/symlink_traversal
@@ -0,0 +1 @@
+^samba3.blackbox.test_symlink_traversal.SMB2.symlink_traversal_SMB2\(fileserver\)
diff --git a/source3/script/tests/test_symlink_traversal_smb2.sh b/source3/script/tests/test_symlink_traversal_smb2.sh
new file mode 100755
index 00000000000..7e1de6dde1a
--- /dev/null
+++ b/source3/script/tests/test_symlink_traversal_smb2.sh
@@ -0,0 +1,263 @@
+#!/bin/sh
+
+if [ $# -lt 7 ]; then
+cat <<EOF
+Usage: test_symlink_traversal_smb2.sh SERVER SERVER_IP USERNAME PASSWORD LOCAL_PATH PREFIX SMBCLIENT
+EOF
+exit 1;
+fi
+
+SERVER="${1}"
+SERVER_IP="${2}"
+USERNAME="${3}"
+PASSWORD="${4}"
+LOCAL_PATH="${5}"
+PREFIX="${6}"
+SMBCLIENT="${7}"
+SMBCLIENT="$VALGRIND ${SMBCLIENT}"
+shift 6
+
+incdir=$(dirname "$0")/../../../testprogs/blackbox
+. "$incdir"/subunit.sh
+
+failed=0
+
+# Do not let deprecated option warnings muck this up
+SAMBA_DEPRECATED_SUPPRESS=1
+export SAMBA_DEPRECATED_SUPPRESS
+
+
+# Define the test environment/filenames.
+#
+share_test_dir="$LOCAL_PATH"
+#
+# These files/directories will be created.
+#
+file_outside_share="/tmp/symlink_traverse_test_file.$$"
+dir_outside_share="/tmp/symlink_traverse_test_dir.$$"
+file_outside_share_noperms="/tmp/symlink_traverse_test_file_noperm.$$"
+dir_outside_share_noperms="/tmp/symlink_traverse_test_dir_noperm.$$"
+#
+# These two objects do not exist.
+#
+file_outside_share_noexist="/tmp/symlink_traverse_test_noexist.$$"
+dir_outside_share_noexist="/tmp/symlink_traverse_test_dir_noexist.$$"
+
+#
+# Cleanup function.
+#
+do_cleanup()
+{
+(
+#subshell.
+cd "$share_test_dir" || return
+rm -f "file_exists"
+rm -f "symlink_noexist"
+rm -f "symlink_file_outside_share"
+rm -f "symlink_file_outside_share_noexist"
+rm -f "symlink_dir_outside_share"
+rm -f "symlink_dir_outside_share_noexist"
+rm -f "symlink_file_outside_share_noperms"
+rm -f "symlink_dir_outside_share_noperms"
+rm -rf "emptydir"
+# Links inside share.
+rm -f "symlink_file_inside_share_noperms"
+rm -f "file_inside_share_noperms"
+rm -f "symlink_dir_inside_share_noperms"
+chmod 755 "dir_inside_share_noperms"
+rm -rf "dir_inside_share_noperms"
+)
+rm -f "$file_outside_share"
+rm -rf "$dir_outside_share"
+rm -f "$file_outside_share_noperms"
+rm -rf "$dir_outside_share_noperms"
+}
+
+#
+# Ensure we start from a clean slate.
+#
+do_cleanup
+
+#
+# Create the test files/directories/symlinks.
+#
+# File/directory explicitly outside share.
+touch "$file_outside_share"
+mkdir "$dir_outside_share"
+# File/directory explicitly outside share with permission denied.
+touch "$file_outside_share_noperms"
+chmod 0 "$file_outside_share_noperms"
+mkdir "$dir_outside_share_noperms"
+chmod 0 "$dir_outside_share_noperms"
+#
+# Create links to these objects inside the share definition.
+(
+#subshell.
+cd "$share_test_dir" || return
+touch "file_exists"
+ln -s "noexist" "symlink_noexist"
+ln -s "$file_outside_share" "symlink_file_outside_share"
+ln -s "$file_outside_share_noexist" "symlink_file_outside_share_noexist"
+ln -s "$dir_outside_share" "symlink_dir_outside_share"
+ln -s "$dir_outside_share_noexist" "symlink_dir_outside_share_noexist"
+ln -s "$file_outside_share_noperms" "symlink_file_outside_share_noperms"
+ln -s "$dir_outside_share_noperms" "symlink_dir_outside_share_noperms"
+#
+# Create the identical symlink set underneath "emptydir"
+mkdir "emptydir"
+(
+#subshell
+cd "emptydir" || return
+touch "file_exists"
+ln -s "noexist" "symlink_noexist"
+ln -s "$file_outside_share" "symlink_file_outside_share"
+ln -s "$file_outside_share_noexist" "symlink_file_outside_share_noexist"
+ln -s "$dir_outside_share" "symlink_dir_outside_share"
+ln -s "$dir_outside_share_noexist" "symlink_dir_outside_share_noexist"
+ln -s "$file_outside_share_noperms" "symlink_file_outside_share_noperms"
+ln -s "$dir_outside_share_noperms" "symlink_dir_outside_share_noperms"
+)
+#
+# Create symlinks to access denied file and directory
+# objects within the share
+touch "file_inside_share_noperms"
+chmod 0 "file_inside_share_noperms"
+ln -s "file_inside_share_noperms" "symlink_file_inside_share_noperms"
+mkdir "dir_inside_share_noperms"
+touch "dir_inside_share_noperms/noperm_file_exists"
+chmod 0 "dir_inside_share_noperms"
+ln -s "dir_inside_share_noperms" "symlink_dir_inside_share_noperms"
+)
+
+#
+# smbclient function given command, path, expected error, and posix.
+#
+smbclient_expect_error()
+{
+    filecmd="$1"
+    filename1="$2"
+    filename2="$3"
+    expected_error="$4"
+    tmpfile=$PREFIX/smbclient_interactive_prompt_commands
+    cat > "$tmpfile" <<EOF
+$filecmd $filename1 $filename2
+quit
+EOF
+    cmd='CLI_FORCE_INTERACTIVE=yes $SMBCLIENT -U$USERNAME%$PASSWORD //$SERVER/local_symlinks -I$SERVER_IP < $tmpfile 2>&1'
+    eval echo "$cmd"
+    out=$(eval "$cmd")
+    ret=$?
+    rm -f "$tmpfile"
+
+    if [ $ret != 0 ] ; then
+	printf "%s\n" "$out"
+	printf "failed accessing local_symlinks with error %s\n" "$ret"
+	return 1
+    fi
+
+    if [ "$expected_error" = "NT_STATUS_OK" ] ; then
+        printf "%s" "$out" | grep -v "NT_STATUS_"
+    else
+        printf "%s" "$out" | grep "$expected_error"
+    fi
+    ret=$?
+    if [ $ret != 0 ] ; then
+	printf "%s\n" "$out"
+	printf "failed - should get %s doing \"%s %s %s\"\n" "$expected_error" "$filecmd" "$filename1" "$filename2"
+	return 1
+    fi
+}
+
+#
+# SMB2 tests.
+#
+test_symlink_traversal_SMB2_onename()
+{
+name="$1"
+do_rename="$2"
+#
+# get commands.
+#
+    smbclient_expect_error "get" "$name" "" "NT_STATUS_OBJECT_NAME_NOT_FOUND" || return 1
+    smbclient_expect_error "get" "$name/noexist" "" "NT_STATUS_OBJECT_PATH_NOT_FOUND" || return 1
+    smbclient_expect_error "get" "$name/*" "" "NT_STATUS_OBJECT_NAME_INVALID" || return 1
+    smbclient_expect_error "get" "$name/*/noexist" "" "NT_STATUS_OBJECT_NAME_INVALID" || return 1
+# Now in subdirectory emptydir
+    smbclient_expect_error "get" "emptydir/$name" "" "NT_STATUS_OBJECT_NAME_NOT_FOUND" || return 1
+    smbclient_expect_error "get" "emptydir/$name/noexist" "" "NT_STATUS_OBJECT_PATH_NOT_FOUND" || return 1
+    smbclient_expect_error "get" "emptydir/$name/*" "" "NT_STATUS_OBJECT_NAME_INVALID" || return 1
+    smbclient_expect_error "get" "emptydir/$name/*/noexist" "" "NT_STATUS_OBJECT_NAME_INVALID" || return 1
+#
+# ls commands.
+#
+    smbclient_expect_error "ls" "$name" "" "NT_STATUS_NO_SUCH_FILE" || return 1
+    smbclient_expect_error "ls" "$name/noexist" "" "NT_STATUS_OBJECT_NAME_NOT_FOUND" || return 1
+    smbclient_expect_error "ls" "$name/*" "" "NT_STATUS_OBJECT_NAME_NOT_FOUND" || return 1
+    smbclient_expect_error "ls" "$name/*/noexist" "" "NT_STATUS_OBJECT_NAME_INVALID" || return 1
+# Now in subdirectory emptydir
+    smbclient_expect_error "ls" "emptydir/$name" "" "NT_STATUS_NO_SUCH_FILE" || return 1
+    smbclient_expect_error "ls" "emptydir/$name/noexist" "" "NT_STATUS_OBJECT_NAME_NOT_FOUND" || return 1
+    smbclient_expect_error "ls" "emptydir/$name/*" "" "NT_STATUS_OBJECT_NAME_NOT_FOUND" || return 1
+    smbclient_expect_error "ls" "emptydir/$name/*/noexist" "" "NT_STATUS_OBJECT_NAME_INVALID" || return 1
+
+#
+# del commands.
+# smbclient internally does a cli_list, so we expect similar errors.
+#
+    smbclient_expect_error "del" "$name" "" "NT_STATUS_NO_SUCH_FILE" || return 1
+    smbclient_expect_error "del" "$name/noexist" "" "NT_STATUS_OBJECT_NAME_NOT_FOUND" || return 1
+# Now in subdirectory emptydir
+    smbclient_expect_error "del" "emptydir/$name" "" "NT_STATUS_NO_SUCH_FILE" || return 1
+    smbclient_expect_error "del" "emptydir/$name/noexist" "" "NT_STATUS_OBJECT_NAME_NOT_FOUND" || return 1
+
+    if [ "$do_rename" = "do rename" ] ; then
+#
+# rename commands.
+#
+		smbclient_expect_error "rename" "file_exists" "$name" "NT_STATUS_OBJECT_NAME_NOT_FOUND" || return 1
+		smbclient_expect_error "rename" "file_exists" "$name/noexist" "NT_STATUS_OBJECT_PATH_NOT_FOUND" || return 1
+# Now in subdirectory emptydir
+		smbclient_expect_error "rename" "file_exists" "emptydir/$name" "NT_STATUS_OBJECT_NAME_NOT_FOUND" || return 1
+		smbclient_expect_error "rename" "file_exists" "emptydir/$name/noexist" "NT_STATUS_OBJECT_PATH_NOT_FOUND" || return 1
+    fi
+    return 0
+}
+
+#
+# Check error code returns traversing through different
+# kinds of symlinks over SMB2.
+#
+test_symlink_traversal_SMB2()
+{
+	test_symlink_traversal_SMB2_onename "symlink_noexist" "no rename" || return 1
+	test_symlink_traversal_SMB2_onename "symlink_file_outside_share" "do rename" || return 1
+	test_symlink_traversal_SMB2_onename "symlink_dir_outside_share" "do rename" || return 1
+	test_symlink_traversal_SMB2_onename "symlink_dir_outside_share_noexist" "no rename" || return 1
+	test_symlink_traversal_SMB2_onename "symlink_file_outside_share_noperms" "do rename" || return 1
+	test_symlink_traversal_SMB2_onename "symlink_dir_outside_share_noperms" "do rename" || return 1
+#
+# Test paths within share with no permissions.
+#
+# Can't 'get' file with no perms or a symlink to it.
+	smbclient_expect_error "get" "file_inside_share_noperms" "" "NT_STATUS_ACCESS_DENIED" || return 1
+	smbclient_expect_error "get" "symlink_file_inside_share_noperms" "" "NT_STATUS_ACCESS_DENIED" || return 1
+# But can list it and the symlink to it.
+	smbclient_expect_error "ls" "file_inside_share_noperms" "" "NT_STATUS_OK" || return 1
+	smbclient_expect_error "ls" "symlink_file_inside_share_noperms" "" "NT_STATUS_OK" || return 1
+# Can't 'get' file inside a directory with no perms or a symlink to it.
+	smbclient_expect_error "get" "dir_inside_share_noperms/noperm_file_exists" "" "NT_STATUS_ACCESS_DENIED" || return 1
+	smbclient_expect_error "get" "symlink_dir_inside_share_noperms/noperm_file_exists" "" "NT_STATUS_ACCESS_DENIED" || return 1
+# But can list the directory with no perms and the symlink to it.
+	smbclient_expect_error "ls" "dir_inside_share_noperms" "" "NT_STATUS_OK" || return 1
+	smbclient_expect_error "ls" "symlink_dir_inside_share_noperms" "" "NT_STATUS_OK" || return 1
+}
+
+testit "symlink_traversal_SMB2" \
+	test_symlink_traversal_SMB2 || \
+	failed=$((failed+1))
+
+#
+# Cleanup.
+do_cleanup
+
+testok "$0" "$failed"
diff --git a/source3/selftest/tests.py b/source3/selftest/tests.py
index 4a09a92bf24..539cbd42e5c 100755
--- a/source3/selftest/tests.py
+++ b/source3/selftest/tests.py
@@ -579,6 +579,12 @@ for env in ["fileserver"]:
                   smbclient3,
                   "-mSMB3"])
 
+    plantestsuite("samba3.blackbox.test_symlink_traversal.SMB2", env,
+                  [os.path.join(samba3srcdir, "script/tests/test_symlink_traversal_smb2.sh"),
+                  '$SERVER', '$SERVER_IP', '$USERNAME', '$PASSWORD', '$LOCAL_PATH/local_symlinks',
+                  '$PREFIX', smbclient3])
+
+
     #
     # tar command tests
     #