Coverage Report

Created: 2026-09-14 20:36

next uncovered line (L), next uncovered region (R), next uncovered branch (B)
/tmp/bitcoin/src/univalue/lib/univalue_read.cpp
Line
Count
Source
1
// Copyright 2014 BitPay Inc.
2
// Copyright (c) 2015-present The Bitcoin Core developers
3
// Distributed under the MIT software license, see the accompanying
4
// file COPYING or https://opensource.org/licenses/mit-license.php.
5
6
#include <univalue.h>
7
#include <univalue_utffilter.h>
8
9
#include <cstdint>
10
#include <cstring>
11
#include <string>
12
#include <string_view>
13
#include <utility>
14
#include <vector>
15
16
/*
17
 * According to stackexchange, the original json test suite wanted
18
 * to limit depth to 22.  Widely-deployed PHP bails at depth 512,
19
 * so we will follow PHP's lead, which should be more than sufficient
20
 * (further stackexchange comments indicate depth > 32 rarely occurs).
21
 */
22
static constexpr size_t MAX_JSON_DEPTH = 512;
23
24
static bool json_isdigit(int ch)
25
8.18M
{
26
8.18M
    return ((ch >= '0') && (ch <= '9'));
27
8.18M
}
28
29
// convert hexadecimal string to unsigned integer
30
static const char *hatoui(const char *first, const char *last,
31
                          unsigned int& out)
32
682
{
33
682
    unsigned int result = 0;
34
3.41k
    for (; first != last; ++first)
35
2.72k
    {
36
2.72k
        int digit;
37
2.72k
        if (json_isdigit(*first))
38
1.38k
            digit = *first - '0';
39
40
1.34k
        else if (*first >= 'a' && *first <= 'f')
41
1.32k
            digit = *first - 'a' + 10;
42
43
22
        else if (*first >= 'A' && *first <= 'F')
44
22
            digit = *first - 'A' + 10;
45
46
0
        else
47
0
            break;
48
49
2.72k
        result = 16 * result + digit;
50
2.72k
    }
51
682
    out = result;
52
53
682
    return first;
54
682
}
55
56
enum jtokentype getJsonToken(std::string& tokenVal, unsigned int& consumed,
57
                            const char *raw, const char *end)
58
6.84M
{
59
6.84M
    tokenVal.clear();
60
6.84M
    consumed = 0;
61
62
6.84M
    const char *rawStart = raw;
63
64
8.77M
    while (raw < end && (json_isspace(*raw)))          // skip whitespace
65
1.93M
        raw++;
66
67
6.84M
    if (raw >= end)
68
187k
        return JTOK_NONE;
69
70
6.65M
    switch (*raw) {
71
72
324k
    case '{':
73
324k
        raw++;
74
324k
        consumed = (raw - rawStart);
75
324k
        return JTOK_OBJ_OPEN;
76
324k
    case '}':
77
324k
        raw++;
78
324k
        consumed = (raw - rawStart);
79
324k
        return JTOK_OBJ_CLOSE;
80
124k
    case '[':
81
124k
        raw++;
82
124k
        consumed = (raw - rawStart);
83
124k
        return JTOK_ARR_OPEN;
84
123k
    case ']':
85
123k
        raw++;
86
123k
        consumed = (raw - rawStart);
87
123k
        return JTOK_ARR_CLOSE;
88
89
962k
    case ':':
90
962k
        raw++;
91
962k
        consumed = (raw - rawStart);
92
962k
        return JTOK_COLON;
93
930k
    case ',':
94
930k
        raw++;
95
930k
        consumed = (raw - rawStart);
96
930k
        return JTOK_COMMA;
97
98
796
    case 'n':
99
16.8k
    case 't':
100
19.2k
    case 'f':
101
19.2k
        if (!strncmp(raw, "null", 4)) {
102
794
            raw += 4;
103
794
            consumed = (raw - rawStart);
104
794
            return JTOK_KW_NULL;
105
18.4k
        } else if (!strncmp(raw, "true", 4)) {
106
16.0k
            raw += 4;
107
16.0k
            consumed = (raw - rawStart);
108
16.0k
            return JTOK_KW_TRUE;
109
16.0k
        } else if (!strncmp(raw, "false", 5)) {
110
2.40k
            raw += 5;
111
2.40k
            consumed = (raw - rawStart);
112
2.40k
            return JTOK_KW_FALSE;
113
2.40k
        } else
114
7
            return JTOK_ERR;
115
116
40.6k
    case '-':
117
429k
    case '0':
118
1.09M
    case '1':
119
1.41M
    case '2':
120
1.60M
    case '3':
121
1.74M
    case '4':
122
1.81M
    case '5':
123
1.90M
    case '6':
124
1.96M
    case '7':
125
2.07M
    case '8':
126
2.14M
    case '9': {
127
        // part 1: int
128
2.14M
        std::string numStr;
129
130
2.14M
        const char *first = raw;
131
132
2.14M
        const char *firstDigit = first;
133
2.14M
        if (!json_isdigit(*firstDigit))
134
40.6k
            firstDigit++;
135
2.14M
        if ((*firstDigit == '0') && json_isdigit(firstDigit[1]))
136
1
            return JTOK_ERR;
137
138
2.14M
        numStr += *raw;                       // copy first char
139
2.14M
        raw++;
140
141
2.14M
        if ((*first == '-') && (raw < end) && (!json_isdigit(*raw)))
142
0
            return JTOK_ERR;
143
144
6.72M
        while (raw < end && json_isdigit(*raw)) {  // copy digits
145
4.58M
            numStr += *raw;
146
4.58M
            raw++;
147
4.58M
        }
148
149
        // part 2: frac
150
2.14M
        if (raw < end && *raw == '.') {
151
54.9k
            numStr += *raw;                   // copy .
152
54.9k
            raw++;
153
154
54.9k
            if (raw >= end || !json_isdigit(*raw))
155
0
                return JTOK_ERR;
156
581k
            while (raw < end && json_isdigit(*raw)) { // copy digits
157
526k
                numStr += *raw;
158
526k
                raw++;
159
526k
            }
160
54.9k
        }
161
162
        // part 3: exp
163
2.14M
        if (raw < end && (*raw == 'e' || *raw == 'E')) {
164
24.2k
            numStr += *raw;                   // copy E
165
24.2k
            raw++;
166
167
24.2k
            if (raw < end && (*raw == '-' || *raw == '+')) { // copy +/-
168
24.1k
                numStr += *raw;
169
24.1k
                raw++;
170
24.1k
            }
171
172
24.2k
            if (raw >= end || !json_isdigit(*raw))
173
3
                return JTOK_ERR;
174
72.5k
            while (raw < end && json_isdigit(*raw)) { // copy digits
175
48.3k
                numStr += *raw;
176
48.3k
                raw++;
177
48.3k
            }
178
24.1k
        }
179
180
2.14M
        tokenVal = numStr;
181
2.14M
        consumed = (raw - rawStart);
182
2.14M
        return JTOK_NUMBER;
183
2.14M
        }
184
185
1.69M
    case '"': {
186
1.69M
        raw++;                                // skip "
187
188
1.69M
        std::string valStr;
189
1.69M
        JSONUTF8StringFilter writer(valStr);
190
191
1.21G
        while (true) {
192
1.21G
            if (raw >= end || (unsigned char)*raw < 0x20)
193
4
                return JTOK_ERR;
194
195
1.21G
            else if (*raw == '\\') {
196
736
                raw++;                        // skip backslash
197
198
736
                if (raw >= end)
199
0
                    return JTOK_ERR;
200
201
736
                switch (*raw) {
202
15
                case '"':  writer.push_back('\"'); break;
203
5
                case '\\': writer.push_back('\\'); break;
204
2
                case '/':  writer.push_back('/'); break;
205
5
                case 'b':  writer.push_back('\b'); break;
206
5
                case 'f':  writer.push_back('\f'); break;
207
8
                case 'n':  writer.push_back('\n'); break;
208
5
                case 'r':  writer.push_back('\r'); break;
209
5
                case 't':  writer.push_back('\t'); break;
210
211
682
                case 'u': {
212
682
                    unsigned int codepoint;
213
682
                    if (raw + 1 + 4 >= end ||
214
682
                        hatoui(raw + 1, raw + 1 + 4, codepoint) !=
215
682
                               raw + 1 + 4)
216
0
                        return JTOK_ERR;
217
682
                    writer.push_back_u(codepoint);
218
682
                    raw += 4;
219
682
                    break;
220
682
                    }
221
4
                default:
222
4
                    return JTOK_ERR;
223
224
736
                }
225
226
732
                raw++;                        // skip esc'd char
227
732
            }
228
229
1.21G
            else if (*raw == '"') {
230
1.69M
                raw++;                        // skip "
231
1.69M
                break;                        // stop scanning
232
1.69M
            }
233
234
1.21G
            else {
235
1.21G
                writer.push_back(static_cast<unsigned char>(*raw));
236
1.21G
                raw++;
237
1.21G
            }
238
1.21G
        }
239
240
1.69M
        if (!writer.finalize())
241
4
            return JTOK_ERR;
242
1.69M
        tokenVal = valStr;
243
1.69M
        consumed = (raw - rawStart);
244
1.69M
        return JTOK_STRING;
245
1.69M
        }
246
247
27
    default:
248
27
        return JTOK_ERR;
249
6.65M
    }
250
6.65M
}
251
252
enum expect_bits : unsigned {
253
    EXP_OBJ_NAME = (1U << 0),
254
    EXP_COLON = (1U << 1),
255
    EXP_ARR_VALUE = (1U << 2),
256
    EXP_VALUE = (1U << 3),
257
    EXP_NOT_VALUE = (1U << 4),
258
};
259
260
24.1M
#define expect(bit) (expectMask & (EXP_##bit))
261
5.76M
#define setExpect(bit) (expectMask |= EXP_##bit)
262
5.96M
#define clearExpect(bit) (expectMask &= ~EXP_##bit)
263
264
bool UniValue::read(std::string_view json)
265
187k
{
266
187k
    UniValue parsed;
267
187k
    if (!parsed.read_impl(json)) {
268
81
        setNull();
269
81
        return false;
270
81
    }
271
187k
    *this = std::move(parsed);
272
187k
    return true;
273
187k
}
274
275
bool UniValue::read_impl(std::string_view str_in)
276
187k
{
277
187k
    clear();
278
279
187k
    uint32_t expectMask = 0;
280
187k
    std::vector<UniValue*> stack;
281
282
187k
    std::string tokenVal;
283
187k
    unsigned int consumed;
284
187k
    enum jtokentype tok = JTOK_NONE;
285
187k
    enum jtokentype last_tok = JTOK_NONE;
286
187k
    const char* raw{str_in.data()};
287
187k
    const char* end{raw + str_in.size()};
288
4.80M
    do {
289
4.80M
        last_tok = tok;
290
291
4.80M
        tok = getJsonToken(tokenVal, consumed, raw, end);
292
4.80M
        if (tok == JTOK_NONE || tok == JTOK_ERR)
293
49
            return false;
294
4.80M
        raw += consumed;
295
296
4.80M
        bool isValueOpen = jsonTokenIsValue(tok) ||
297
4.80M
            tok == JTOK_OBJ_OPEN || tok == JTOK_ARR_OPEN;
298
299
4.80M
        if (expect(VALUE)) {
300
962k
            if (!isValueOpen)
301
2
                return false;
302
962k
            clearExpect(VALUE);
303
304
3.84M
        } else if (expect(ARR_VALUE)) {
305
353k
            bool isArrValue = isValueOpen || (tok == JTOK_ARR_CLOSE);
306
353k
            if (!isArrValue)
307
2
                return false;
308
309
353k
            clearExpect(ARR_VALUE);
310
311
3.48M
        } else if (expect(OBJ_NAME)) {
312
1.02M
            bool isObjName = (tok == JTOK_OBJ_CLOSE || tok == JTOK_STRING);
313
1.02M
            if (!isObjName)
314
4
                return false;
315
316
2.46M
        } else if (expect(COLON)) {
317
962k
            if (tok != JTOK_COLON)
318
3
                return false;
319
962k
            clearExpect(COLON);
320
321
1.50M
        } else if (!expect(COLON) && (tok == JTOK_COLON)) {
322
1
            return false;
323
1
        }
324
325
4.80M
        if (expect(NOT_VALUE)) {
326
2.27M
            if (isValueOpen)
327
2
                return false;
328
2.27M
            clearExpect(NOT_VALUE);
329
2.27M
        }
330
331
4.80M
        switch (tok) {
332
333
324k
        case JTOK_OBJ_OPEN:
334
449k
        case JTOK_ARR_OPEN: {
335
449k
            VType utyp = (tok == JTOK_OBJ_OPEN ? VOBJ : VARR);
336
449k
            if (!stack.size()) {
337
187k
                if (utyp == VOBJ)
338
186k
                    setObject();
339
737
                else
340
737
                    setArray();
341
187k
                stack.push_back(this);
342
261k
            } else {
343
261k
                UniValue tmpVal(utyp);
344
261k
                UniValue *top = stack.back();
345
261k
                top->values.push_back(tmpVal);
346
347
261k
                UniValue *newTop = &(top->values.back());
348
261k
                stack.push_back(newTop);
349
261k
            }
350
351
449k
            if (stack.size() > MAX_JSON_DEPTH)
352
2
                return false;
353
354
449k
            if (utyp == VOBJ)
355
324k
                setExpect(OBJ_NAME);
356
124k
            else
357
124k
                setExpect(ARR_VALUE);
358
449k
            break;
359
449k
            }
360
361
324k
        case JTOK_OBJ_CLOSE:
362
448k
        case JTOK_ARR_CLOSE: {
363
448k
            if (!stack.size() || (last_tok == JTOK_COMMA))
364
2
                return false;
365
366
448k
            VType utyp = (tok == JTOK_OBJ_CLOSE ? VOBJ : VARR);
367
448k
            UniValue *top = stack.back();
368
448k
            if (utyp != top->getType())
369
1
                return false;
370
371
448k
            stack.pop_back();
372
448k
            clearExpect(OBJ_NAME);
373
448k
            setExpect(NOT_VALUE);
374
448k
            break;
375
448k
            }
376
377
962k
        case JTOK_COLON: {
378
962k
            if (!stack.size())
379
0
                return false;
380
381
962k
            UniValue *top = stack.back();
382
962k
            if (top->getType() != VOBJ)
383
0
                return false;
384
385
962k
            setExpect(VALUE);
386
962k
            break;
387
962k
            }
388
389
930k
        case JTOK_COMMA: {
390
930k
            if (!stack.size() ||
391
930k
                (last_tok == JTOK_COMMA) || (last_tok == JTOK_ARR_OPEN))
392
0
                return false;
393
394
930k
            UniValue *top = stack.back();
395
930k
            if (top->getType() == VOBJ)
396
701k
                setExpect(OBJ_NAME);
397
228k
            else
398
228k
                setExpect(ARR_VALUE);
399
930k
            break;
400
930k
            }
401
402
793
        case JTOK_KW_NULL:
403
16.8k
        case JTOK_KW_TRUE:
404
19.2k
        case JTOK_KW_FALSE: {
405
19.2k
            UniValue tmpVal;
406
19.2k
            switch (tok) {
407
793
            case JTOK_KW_NULL:
408
                // do nothing more
409
793
                break;
410
16.0k
            case JTOK_KW_TRUE:
411
16.0k
                tmpVal.setBool(true);
412
16.0k
                break;
413
2.40k
            case JTOK_KW_FALSE:
414
2.40k
                tmpVal.setBool(false);
415
2.40k
                break;
416
0
            default: /* impossible */ break;
417
19.2k
            }
418
419
19.2k
            if (!stack.size()) {
420
40
                *this = tmpVal;
421
40
                break;
422
40
            }
423
424
19.2k
            UniValue *top = stack.back();
425
19.2k
            top->values.push_back(tmpVal);
426
427
19.2k
            setExpect(NOT_VALUE);
428
19.2k
            break;
429
19.2k
            }
430
431
296k
        case JTOK_NUMBER: {
432
296k
            UniValue tmpVal(VNUM, tokenVal);
433
296k
            if (!stack.size()) {
434
69
                *this = tmpVal;
435
69
                break;
436
69
            }
437
438
296k
            UniValue *top = stack.back();
439
296k
            top->values.push_back(tmpVal);
440
441
296k
            setExpect(NOT_VALUE);
442
296k
            break;
443
296k
            }
444
445
1.69M
        case JTOK_STRING: {
446
1.69M
            if (expect(OBJ_NAME)) {
447
962k
                UniValue *top = stack.back();
448
962k
                top->keys.push_back(tokenVal);
449
962k
                clearExpect(OBJ_NAME);
450
962k
                setExpect(COLON);
451
962k
            } else {
452
736k
                UniValue tmpVal(VSTR, tokenVal);
453
736k
                if (!stack.size()) {
454
3
                    *this = tmpVal;
455
3
                    break;
456
3
                }
457
736k
                UniValue *top = stack.back();
458
736k
                top->values.push_back(tmpVal);
459
736k
            }
460
461
1.69M
            setExpect(NOT_VALUE);
462
1.69M
            break;
463
1.69M
            }
464
465
0
        default:
466
0
            return false;
467
4.80M
        }
468
4.80M
    } while (!stack.empty ());
469
470
    /* Check that nothing follows the initial construct (parsed above).  */
471
187k
    tok = getJsonToken(tokenVal, consumed, raw, end);
472
187k
    if (tok != JTOK_NONE)
473
13
        return false;
474
475
187k
    return true;
476
187k
}