qemu/scripts/qapi-commands.py
Marc-André Lureau a0067da157 qapi: check invalid arguments on no-args commands
The generated marshal functions do not visit arguments from commands
that take no arguments. Thus they fail to catch invalid
members. Visit the arguments, if provided, to throw an error in case of
invalid members.

Currently, qmp_check_client_args() checks for invalid arguments and
correctly catches this case. When switching to qmp_dispatch() we want to
keep that behaviour. The commands using 'O' may have arbitrary
arguments, and must have 'gen': false in the qapi schema to skip the
generated checks.

Old/new diff:
 void qmp_marshal_stop(QDict *args, QObject **ret, Error **errp)
 {
     Error *err = NULL;
+    Visitor *v = NULL;

-    (void)args;
+    if (args) {
+        v = qmp_input_visitor_new(QOBJECT(args), true);
+        visit_start_struct(v, NULL, NULL, 0, &err);
+        if (err) {
+            goto out;
+        }
+
+        if (!err) {
+            visit_check_struct(v, &err);
+        }
+        visit_end_struct(v, NULL);
+        if (err) {
+            goto out;
+        }
+    }

     qmp_stop(&err);
+
+out:
     error_propagate(errp, err);
+    visit_free(v);
+    if (args) {
+        v = qapi_dealloc_visitor_new();
+        visit_start_struct(v, NULL, NULL, 0, NULL);
+
+        visit_end_struct(v, NULL);
+        visit_free(v);
+    }
 }

The new code closely resembles code for a command with arguments.
Differences:
- the visit of the argument and its cleanup struct don't visit any
  members (because there are none).
- the visit of the argument struct and its cleanup are conditional.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20160912091913.15831-14-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-09-19 17:32:22 +02:00

321 lines
7.2 KiB
Python

#
# QAPI command marshaller generator
#
# Copyright IBM, Corp. 2011
# Copyright (C) 2014-2016 Red Hat, Inc.
#
# Authors:
# Anthony Liguori <aliguori@us.ibm.com>
# Michael Roth <mdroth@linux.vnet.ibm.com>
# Markus Armbruster <armbru@redhat.com>
#
# This work is licensed under the terms of the GNU GPL, version 2.
# See the COPYING file in the top-level directory.
from qapi import *
import re
def gen_command_decl(name, arg_type, boxed, ret_type):
return mcgen('''
%(c_type)s qmp_%(c_name)s(%(params)s);
''',
c_type=(ret_type and ret_type.c_type()) or 'void',
c_name=c_name(name),
params=gen_params(arg_type, boxed, 'Error **errp'))
def gen_call(name, arg_type, boxed, ret_type):
ret = ''
argstr = ''
if boxed:
assert arg_type and not arg_type.is_empty()
argstr = '&arg, '
elif arg_type:
assert not arg_type.variants
for memb in arg_type.members:
if memb.optional:
argstr += 'arg.has_%s, ' % c_name(memb.name)
argstr += 'arg.%s, ' % c_name(memb.name)
lhs = ''
if ret_type:
lhs = 'retval = '
ret = mcgen('''
%(lhs)sqmp_%(c_name)s(%(args)s&err);
''',
c_name=c_name(name), args=argstr, lhs=lhs)
if ret_type:
ret += mcgen('''
if (err) {
goto out;
}
qmp_marshal_output_%(c_name)s(retval, ret, &err);
''',
c_name=ret_type.c_name())
return ret
def gen_marshal_output(ret_type):
return mcgen('''
static void qmp_marshal_output_%(c_name)s(%(c_type)s ret_in, QObject **ret_out, Error **errp)
{
Error *err = NULL;
Visitor *v;
v = qmp_output_visitor_new(ret_out);
visit_type_%(c_name)s(v, "unused", &ret_in, &err);
if (!err) {
visit_complete(v, ret_out);
}
error_propagate(errp, err);
visit_free(v);
v = qapi_dealloc_visitor_new();
visit_type_%(c_name)s(v, "unused", &ret_in, NULL);
visit_free(v);
}
''',
c_type=ret_type.c_type(), c_name=ret_type.c_name())
def gen_marshal_proto(name):
return 'void qmp_marshal_%s(QDict *args, QObject **ret, Error **errp)' % c_name(name)
def gen_marshal_decl(name):
return mcgen('''
%(proto)s;
''',
proto=gen_marshal_proto(name))
def gen_marshal(name, arg_type, boxed, ret_type):
have_args = arg_type and not arg_type.is_empty()
ret = mcgen('''
%(proto)s
{
Error *err = NULL;
''',
proto=gen_marshal_proto(name))
if ret_type:
ret += mcgen('''
%(c_type)s retval;
''',
c_type=ret_type.c_type())
if have_args:
visit_members = ('visit_type_%s_members(v, &arg, &err);'
% arg_type.c_name())
ret += mcgen('''
Visitor *v;
%(c_name)s arg = {0};
''',
c_name=arg_type.c_name())
else:
visit_members = ''
ret += mcgen('''
Visitor *v = NULL;
if (args) {
''')
push_indent()
ret += mcgen('''
v = qmp_input_visitor_new(QOBJECT(args), true);
visit_start_struct(v, NULL, NULL, 0, &err);
if (err) {
goto out;
}
%(visit_members)s
if (!err) {
visit_check_struct(v, &err);
}
visit_end_struct(v, NULL);
if (err) {
goto out;
}
''',
visit_members=visit_members)
if not have_args:
pop_indent()
ret += mcgen('''
}
''')
ret += gen_call(name, arg_type, boxed, ret_type)
ret += mcgen('''
out:
error_propagate(errp, err);
visit_free(v);
''')
if have_args:
visit_members = ('visit_type_%s_members(v, &arg, NULL);'
% arg_type.c_name())
else:
visit_members = ''
ret += mcgen('''
if (args) {
''')
push_indent()
ret += mcgen('''
v = qapi_dealloc_visitor_new();
visit_start_struct(v, NULL, NULL, 0, NULL);
%(visit_members)s
visit_end_struct(v, NULL);
visit_free(v);
''',
visit_members=visit_members)
if not have_args:
pop_indent()
ret += mcgen('''
}
''')
ret += mcgen('''
}
''')
return ret
def gen_register_command(name, success_response):
options = 'QCO_NO_OPTIONS'
if not success_response:
options = 'QCO_NO_SUCCESS_RESP'
ret = mcgen('''
qmp_register_command("%(name)s", qmp_marshal_%(c_name)s, %(opts)s);
''',
name=name, c_name=c_name(name),
opts=options)
return ret
def gen_registry(registry):
ret = mcgen('''
static void qmp_init_marshal(void)
{
''')
ret += registry
ret += mcgen('''
}
qapi_init(qmp_init_marshal);
''')
return ret
class QAPISchemaGenCommandVisitor(QAPISchemaVisitor):
def __init__(self):
self.decl = None
self.defn = None
self._regy = None
self._visited_ret_types = None
def visit_begin(self, schema):
self.decl = ''
self.defn = ''
self._regy = ''
self._visited_ret_types = set()
def visit_end(self):
self.defn += gen_registry(self._regy)
self._regy = None
self._visited_ret_types = None
def visit_command(self, name, info, arg_type, ret_type,
gen, success_response, boxed):
if not gen:
return
self.decl += gen_command_decl(name, arg_type, boxed, ret_type)
if ret_type and ret_type not in self._visited_ret_types:
self._visited_ret_types.add(ret_type)
self.defn += gen_marshal_output(ret_type)
self.decl += gen_marshal_decl(name)
self.defn += gen_marshal(name, arg_type, boxed, ret_type)
self._regy += gen_register_command(name, success_response)
(input_file, output_dir, do_c, do_h, prefix, opts) = parse_command_line()
c_comment = '''
/*
* schema-defined QMP->QAPI command dispatch
*
* Copyright IBM, Corp. 2011
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
* See the COPYING.LIB file in the top-level directory.
*
*/
'''
h_comment = '''
/*
* schema-defined QAPI function prototypes
*
* Copyright IBM, Corp. 2011
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
* See the COPYING.LIB file in the top-level directory.
*
*/
'''
(fdef, fdecl) = open_output(output_dir, do_c, do_h, prefix,
'qmp-marshal.c', 'qmp-commands.h',
c_comment, h_comment)
fdef.write(mcgen('''
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "qemu/module.h"
#include "qapi/qmp/types.h"
#include "qapi/qmp/dispatch.h"
#include "qapi/visitor.h"
#include "qapi/qmp-output-visitor.h"
#include "qapi/qmp-input-visitor.h"
#include "qapi/dealloc-visitor.h"
#include "%(prefix)sqapi-types.h"
#include "%(prefix)sqapi-visit.h"
#include "%(prefix)sqmp-commands.h"
''',
prefix=prefix))
fdecl.write(mcgen('''
#include "%(prefix)sqapi-types.h"
#include "qapi/qmp/qdict.h"
#include "qapi/error.h"
''',
prefix=prefix))
schema = QAPISchema(input_file)
gen = QAPISchemaGenCommandVisitor()
schema.visit(gen)
fdef.write(gen.defn)
fdecl.write(gen.decl)
close_output(fdef, fdecl)