]>
git.proxmox.com Git - mirror_qemu.git/blob - qobject/json-streamer.c
2 * JSON streaming support
4 * Copyright IBM, Corp. 2009
7 * Anthony Liguori <aliguori@us.ibm.com>
9 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
10 * See the COPYING.LIB file in the top-level directory.
14 #include "qemu/osdep.h"
15 #include "qemu-common.h"
16 #include "qapi/error.h"
17 #include "qapi/qmp/json-lexer.h"
18 #include "qapi/qmp/json-parser.h"
19 #include "qapi/qmp/json-streamer.h"
21 #define MAX_TOKEN_SIZE (64ULL << 20)
22 #define MAX_TOKEN_COUNT (2ULL << 20)
23 #define MAX_NESTING (1 << 10)
25 static void json_message_free_tokens(JSONMessageParser
*parser
)
29 while ((token
= g_queue_pop_head(&parser
->tokens
))) {
34 void json_message_process_token(JSONLexer
*lexer
, GString
*input
,
35 JSONTokenType type
, int x
, int y
)
37 JSONMessageParser
*parser
= container_of(lexer
, JSONMessageParser
, lexer
);
44 parser
->brace_count
++;
47 parser
->brace_count
--;
50 parser
->bracket_count
++;
53 parser
->bracket_count
--;
56 error_setg(&err
, "JSON parse error, stray '%s'", input
->str
);
58 case JSON_END_OF_INPUT
:
59 if (g_queue_is_empty(&parser
->tokens
)) {
62 json
= json_parser_parse(&parser
->tokens
, parser
->ap
, &err
);
69 * Security consideration, we limit total memory allocated per object
70 * and the maximum recursion depth that a message can force.
72 if (parser
->token_size
+ input
->len
+ 1 > MAX_TOKEN_SIZE
) {
73 error_setg(&err
, "JSON token size limit exceeded");
76 if (g_queue_get_length(&parser
->tokens
) + 1 > MAX_TOKEN_COUNT
) {
77 error_setg(&err
, "JSON token count limit exceeded");
80 if (parser
->bracket_count
+ parser
->brace_count
> MAX_NESTING
) {
81 error_setg(&err
, "JSON nesting depth limit exceeded");
85 token
= g_malloc(sizeof(JSONToken
) + input
->len
+ 1);
87 memcpy(token
->str
, input
->str
, input
->len
);
88 token
->str
[input
->len
] = 0;
92 parser
->token_size
+= input
->len
;
94 g_queue_push_tail(&parser
->tokens
, token
);
96 if ((parser
->brace_count
> 0 || parser
->bracket_count
> 0)
97 && parser
->bracket_count
>= 0 && parser
->bracket_count
>= 0) {
101 json
= json_parser_parse(&parser
->tokens
, parser
->ap
, &err
);
104 parser
->brace_count
= 0;
105 parser
->bracket_count
= 0;
106 json_message_free_tokens(parser
);
107 parser
->token_size
= 0;
108 parser
->emit(parser
->opaque
, json
, err
);
111 void json_message_parser_init(JSONMessageParser
*parser
,
112 void (*emit
)(void *opaque
, QObject
*json
,
114 void *opaque
, va_list *ap
)
117 parser
->opaque
= opaque
;
119 parser
->brace_count
= 0;
120 parser
->bracket_count
= 0;
121 g_queue_init(&parser
->tokens
);
122 parser
->token_size
= 0;
124 json_lexer_init(&parser
->lexer
, !!ap
);
127 void json_message_parser_feed(JSONMessageParser
*parser
,
128 const char *buffer
, size_t size
)
130 json_lexer_feed(&parser
->lexer
, buffer
, size
);
133 void json_message_parser_flush(JSONMessageParser
*parser
)
135 json_lexer_flush(&parser
->lexer
);
136 assert(g_queue_is_empty(&parser
->tokens
));
139 void json_message_parser_destroy(JSONMessageParser
*parser
)
141 json_lexer_destroy(&parser
->lexer
);
142 json_message_free_tokens(parser
);