Coverage Report

Created: 2026-05-06 07:53

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
// Distributed under the MIT software license, see the accompanying
3
// file COPYING or https://opensource.org/licenses/mit-license.php.
4
5
#include <univalue.h>
6
#include <univalue_utffilter.h>
7
8
#include <cstdint>
9
#include <cstring>
10
#include <string>
11
#include <string_view>
12
#include <vector>
13
14
/*
15
 * According to stackexchange, the original json test suite wanted
16
 * to limit depth to 22.  Widely-deployed PHP bails at depth 512,
17
 * so we will follow PHP's lead, which should be more than sufficient
18
 * (further stackexchange comments indicate depth > 32 rarely occurs).
19
 */
20
static constexpr size_t MAX_JSON_DEPTH = 512;
21
22
static bool json_isdigit(int ch)
23
7.15M
{
24
7.15M
    return ((ch >= '0') && (ch <= '9'));
25
7.15M
}
26
27
// convert hexadecimal string to unsigned integer
28
static const char *hatoui(const char *first, const char *last,
29
                          unsigned int& out)
30
592
{
31
592
    unsigned int result = 0;
32
2.96k
    for (; first != last; ++first)
33
2.36k
    {
34
2.36k
        int digit;
35
2.36k
        if (json_isdigit(*first))
36
1.17k
            digit = *first - '0';
37
38
1.19k
        else if (*first >= 'a' && *first <= 'f')
39
1.16k
            digit = *first - 'a' + 10;
40
41
22
        else if (*first >= 'A' && *first <= 'F')
42
22
            digit = *first - 'A' + 10;
43
44
0
        else
45
0
            break;
46
47
2.36k
        result = 16 * result + digit;
48
2.36k
    }
49
592
    out = result;
50
51
592
    return first;
52
592
}
53
54
enum jtokentype getJsonToken(std::string& tokenVal, unsigned int& consumed,
55
                            const char *raw, const char *end)
56
6.31M
{
57
6.31M
    tokenVal.clear();
58
6.31M
    consumed = 0;
59
60
6.31M
    const char *rawStart = raw;
61
62
8.11M
    while (raw < end && (json_isspace(*raw)))          // skip whitespace
63
1.80M
        raw++;
64
65
6.31M
    if (raw >= end)
66
175k
        return JTOK_NONE;
67
68
6.14M
    switch (*raw) {
69
70
302k
    case '{':
71
302k
        raw++;
72
302k
        consumed = (raw - rawStart);
73
302k
        return JTOK_OBJ_OPEN;
74
302k
    case '}':
75
302k
        raw++;
76
302k
        consumed = (raw - rawStart);
77
302k
        return JTOK_OBJ_CLOSE;
78
116k
    case '[':
79
116k
        raw++;
80
116k
        consumed = (raw - rawStart);
81
116k
        return JTOK_ARR_OPEN;
82
115k
    case ']':
83
115k
        raw++;
84
115k
        consumed = (raw - rawStart);
85
115k
        return JTOK_ARR_CLOSE;
86
87
891k
    case ':':
88
891k
        raw++;
89
891k
        consumed = (raw - rawStart);
90
891k
        return JTOK_COLON;
91
872k
    case ',':
92
872k
        raw++;
93
872k
        consumed = (raw - rawStart);
94
872k
        return JTOK_COMMA;
95
96
661
    case 'n':
97
16.4k
    case 't':
98
18.6k
    case 'f':
99
18.6k
        if (!strncmp(raw, "null", 4)) {
100
659
            raw += 4;
101
659
            consumed = (raw - rawStart);
102
659
            return JTOK_KW_NULL;
103
17.9k
        } else if (!strncmp(raw, "true", 4)) {
104
15.7k
            raw += 4;
105
15.7k
            consumed = (raw - rawStart);
106
15.7k
            return JTOK_KW_TRUE;
107
15.7k
        } else if (!strncmp(raw, "false", 5)) {
108
2.18k
            raw += 5;
109
2.18k
            consumed = (raw - rawStart);
110
2.18k
            return JTOK_KW_FALSE;
111
2.18k
        } else
112
7
            return JTOK_ERR;
113
114
39.3k
    case '-':
115
418k
    case '0':
116
933k
    case '1':
117
1.24M
    case '2':
118
1.43M
    case '3':
119
1.56M
    case '4':
120
1.62M
    case '5':
121
1.71M
    case '6':
122
1.76M
    case '7':
123
1.87M
    case '8':
124
1.94M
    case '9': {
125
        // part 1: int
126
1.94M
        std::string numStr;
127
128
1.94M
        const char *first = raw;
129
130
1.94M
        const char *firstDigit = first;
131
1.94M
        if (!json_isdigit(*firstDigit))
132
39.3k
            firstDigit++;
133
1.94M
        if ((*firstDigit == '0') && json_isdigit(firstDigit[1]))
134
1
            return JTOK_ERR;
135
136
1.94M
        numStr += *raw;                       // copy first char
137
1.94M
        raw++;
138
139
1.94M
        if ((*first == '-') && (raw < end) && (!json_isdigit(*raw)))
140
0
            return JTOK_ERR;
141
142
5.74M
        while (raw < end && json_isdigit(*raw)) {  // copy digits
143
3.80M
            numStr += *raw;
144
3.80M
            raw++;
145
3.80M
        }
146
147
        // part 2: frac
148
1.94M
        if (raw < end && *raw == '.') {
149
53.6k
            numStr += *raw;                   // copy .
150
53.6k
            raw++;
151
152
53.6k
            if (raw >= end || !json_isdigit(*raw))
153
0
                return JTOK_ERR;
154
567k
            while (raw < end && json_isdigit(*raw)) { // copy digits
155
513k
                numStr += *raw;
156
513k
                raw++;
157
513k
            }
158
53.6k
        }
159
160
        // part 3: exp
161
1.94M
        if (raw < end && (*raw == 'e' || *raw == 'E')) {
162
23.7k
            numStr += *raw;                   // copy E
163
23.7k
            raw++;
164
165
23.7k
            if (raw < end && (*raw == '-' || *raw == '+')) { // copy +/-
166
23.7k
                numStr += *raw;
167
23.7k
                raw++;
168
23.7k
            }
169
170
23.7k
            if (raw >= end || !json_isdigit(*raw))
171
3
                return JTOK_ERR;
172
71.3k
            while (raw < end && json_isdigit(*raw)) { // copy digits
173
47.5k
                numStr += *raw;
174
47.5k
                raw++;
175
47.5k
            }
176
23.7k
        }
177
178
1.94M
        tokenVal = numStr;
179
1.94M
        consumed = (raw - rawStart);
180
1.94M
        return JTOK_NUMBER;
181
1.94M
        }
182
183
1.57M
    case '"': {
184
1.57M
        raw++;                                // skip "
185
186
1.57M
        std::string valStr;
187
1.57M
        JSONUTF8StringFilter writer(valStr);
188
189
654M
        while (true) {
190
654M
            if (raw >= end || (unsigned char)*raw < 0x20)
191
4
                return JTOK_ERR;
192
193
654M
            else if (*raw == '\\') {
194
639
                raw++;                        // skip backslash
195
196
639
                if (raw >= end)
197
0
                    return JTOK_ERR;
198
199
639
                switch (*raw) {
200
14
                case '"':  writer.push_back('\"'); break;
201
4
                case '\\': writer.push_back('\\'); break;
202
2
                case '/':  writer.push_back('/'); break;
203
4
                case 'b':  writer.push_back('\b'); break;
204
4
                case 'f':  writer.push_back('\f'); break;
205
7
                case 'n':  writer.push_back('\n'); break;
206
4
                case 'r':  writer.push_back('\r'); break;
207
4
                case 't':  writer.push_back('\t'); break;
208
209
592
                case 'u': {
210
592
                    unsigned int codepoint;
211
592
                    if (raw + 1 + 4 >= end ||
212
592
                        hatoui(raw + 1, raw + 1 + 4, codepoint) !=
213
592
                               raw + 1 + 4)
214
0
                        return JTOK_ERR;
215
592
                    writer.push_back_u(codepoint);
216
592
                    raw += 4;
217
592
                    break;
218
592
                    }
219
4
                default:
220
4
                    return JTOK_ERR;
221
222
639
                }
223
224
635
                raw++;                        // skip esc'd char
225
635
            }
226
227
654M
            else if (*raw == '"') {
228
1.57M
                raw++;                        // skip "
229
1.57M
                break;                        // stop scanning
230
1.57M
            }
231
232
653M
            else {
233
653M
                writer.push_back(static_cast<unsigned char>(*raw));
234
653M
                raw++;
235
653M
            }
236
654M
        }
237
238
1.57M
        if (!writer.finalize())
239
4
            return JTOK_ERR;
240
1.57M
        tokenVal = valStr;
241
1.57M
        consumed = (raw - rawStart);
242
1.57M
        return JTOK_STRING;
243
1.57M
        }
244
245
26
    default:
246
26
        return JTOK_ERR;
247
6.14M
    }
248
6.14M
}
249
250
enum expect_bits : unsigned {
251
    EXP_OBJ_NAME = (1U << 0),
252
    EXP_COLON = (1U << 1),
253
    EXP_ARR_VALUE = (1U << 2),
254
    EXP_VALUE = (1U << 3),
255
    EXP_NOT_VALUE = (1U << 4),
256
};
257
258
22.4M
#define expect(bit) (expectMask & (EXP_##bit))
259
5.37M
#define setExpect(bit) (expectMask |= EXP_##bit)
260
5.55M
#define clearExpect(bit) (expectMask &= ~EXP_##bit)
261
262
bool UniValue::read(std::string_view str_in)
263
175k
{
264
175k
    clear();
265
266
175k
    uint32_t expectMask = 0;
267
175k
    std::vector<UniValue*> stack;
268
269
175k
    std::string tokenVal;
270
175k
    unsigned int consumed;
271
175k
    enum jtokentype tok = JTOK_NONE;
272
175k
    enum jtokentype last_tok = JTOK_NONE;
273
175k
    const char* raw{str_in.data()};
274
175k
    const char* end{raw + str_in.size()};
275
4.47M
    do {
276
4.47M
        last_tok = tok;
277
278
4.47M
        tok = getJsonToken(tokenVal, consumed, raw, end);
279
4.47M
        if (tok == JTOK_NONE || tok == JTOK_ERR)
280
47
            return false;
281
4.47M
        raw += consumed;
282
283
4.47M
        bool isValueOpen = jsonTokenIsValue(tok) ||
284
4.47M
            tok == JTOK_OBJ_OPEN || tok == JTOK_ARR_OPEN;
285
286
4.47M
        if (expect(VALUE)) {
287
891k
            if (!isValueOpen)
288
2
                return false;
289
891k
            clearExpect(VALUE);
290
291
3.58M
        } else if (expect(ARR_VALUE)) {
292
339k
            bool isArrValue = isValueOpen || (tok == JTOK_ARR_CLOSE);
293
339k
            if (!isArrValue)
294
2
                return false;
295
296
339k
            clearExpect(ARR_VALUE);
297
298
3.24M
        } else if (expect(OBJ_NAME)) {
299
952k
            bool isObjName = (tok == JTOK_OBJ_CLOSE || tok == JTOK_STRING);
300
952k
            if (!isObjName)
301
4
                return false;
302
303
2.29M
        } else if (expect(COLON)) {
304
891k
            if (tok != JTOK_COLON)
305
3
                return false;
306
891k
            clearExpect(COLON);
307
308
1.40M
        } else if (!expect(COLON) && (tok == JTOK_COLON)) {
309
1
            return false;
310
1
        }
311
312
4.47M
        if (expect(NOT_VALUE)) {
313
2.11M
            if (isValueOpen)
314
2
                return false;
315
2.11M
            clearExpect(NOT_VALUE);
316
2.11M
        }
317
318
4.47M
        switch (tok) {
319
320
302k
        case JTOK_OBJ_OPEN:
321
419k
        case JTOK_ARR_OPEN: {
322
419k
            VType utyp = (tok == JTOK_OBJ_OPEN ? VOBJ : VARR);
323
419k
            if (!stack.size()) {
324
175k
                if (utyp == VOBJ)
325
174k
                    setObject();
326
610
                else
327
610
                    setArray();
328
175k
                stack.push_back(this);
329
244k
            } else {
330
244k
                UniValue tmpVal(utyp);
331
244k
                UniValue *top = stack.back();
332
244k
                top->values.push_back(tmpVal);
333
334
244k
                UniValue *newTop = &(top->values.back());
335
244k
                stack.push_back(newTop);
336
244k
            }
337
338
419k
            if (stack.size() > MAX_JSON_DEPTH)
339
2
                return false;
340
341
419k
            if (utyp == VOBJ)
342
302k
                setExpect(OBJ_NAME);
343
116k
            else
344
116k
                setExpect(ARR_VALUE);
345
419k
            break;
346
419k
            }
347
348
302k
        case JTOK_OBJ_CLOSE:
349
418k
        case JTOK_ARR_CLOSE: {
350
418k
            if (!stack.size() || (last_tok == JTOK_COMMA))
351
2
                return false;
352
353
418k
            VType utyp = (tok == JTOK_OBJ_CLOSE ? VOBJ : VARR);
354
418k
            UniValue *top = stack.back();
355
418k
            if (utyp != top->getType())
356
1
                return false;
357
358
418k
            stack.pop_back();
359
418k
            clearExpect(OBJ_NAME);
360
418k
            setExpect(NOT_VALUE);
361
418k
            break;
362
418k
            }
363
364
891k
        case JTOK_COLON: {
365
891k
            if (!stack.size())
366
0
                return false;
367
368
891k
            UniValue *top = stack.back();
369
891k
            if (top->getType() != VOBJ)
370
0
                return false;
371
372
891k
            setExpect(VALUE);
373
891k
            break;
374
891k
            }
375
376
872k
        case JTOK_COMMA: {
377
872k
            if (!stack.size() ||
378
872k
                (last_tok == JTOK_COMMA) || (last_tok == JTOK_ARR_OPEN))
379
0
                return false;
380
381
872k
            UniValue *top = stack.back();
382
872k
            if (top->getType() == VOBJ)
383
649k
                setExpect(OBJ_NAME);
384
222k
            else
385
222k
                setExpect(ARR_VALUE);
386
872k
            break;
387
872k
            }
388
389
658
        case JTOK_KW_NULL:
390
16.4k
        case JTOK_KW_TRUE:
391
18.6k
        case JTOK_KW_FALSE: {
392
18.6k
            UniValue tmpVal;
393
18.6k
            switch (tok) {
394
658
            case JTOK_KW_NULL:
395
                // do nothing more
396
658
                break;
397
15.7k
            case JTOK_KW_TRUE:
398
15.7k
                tmpVal.setBool(true);
399
15.7k
                break;
400
2.18k
            case JTOK_KW_FALSE:
401
2.18k
                tmpVal.setBool(false);
402
2.18k
                break;
403
0
            default: /* impossible */ break;
404
18.6k
            }
405
406
18.6k
            if (!stack.size()) {
407
39
                *this = tmpVal;
408
39
                break;
409
39
            }
410
411
18.5k
            UniValue *top = stack.back();
412
18.5k
            top->values.push_back(tmpVal);
413
414
18.5k
            setExpect(NOT_VALUE);
415
18.5k
            break;
416
18.6k
            }
417
418
278k
        case JTOK_NUMBER: {
419
278k
            UniValue tmpVal(VNUM, tokenVal);
420
278k
            if (!stack.size()) {
421
69
                *this = tmpVal;
422
69
                break;
423
69
            }
424
425
278k
            UniValue *top = stack.back();
426
278k
            top->values.push_back(tmpVal);
427
428
278k
            setExpect(NOT_VALUE);
429
278k
            break;
430
278k
            }
431
432
1.57M
        case JTOK_STRING: {
433
1.57M
            if (expect(OBJ_NAME)) {
434
891k
                UniValue *top = stack.back();
435
891k
                top->keys.push_back(tokenVal);
436
891k
                clearExpect(OBJ_NAME);
437
891k
                setExpect(COLON);
438
891k
            } else {
439
686k
                UniValue tmpVal(VSTR, tokenVal);
440
686k
                if (!stack.size()) {
441
3
                    *this = tmpVal;
442
3
                    break;
443
3
                }
444
686k
                UniValue *top = stack.back();
445
686k
                top->values.push_back(tmpVal);
446
686k
            }
447
448
1.57M
            setExpect(NOT_VALUE);
449
1.57M
            break;
450
1.57M
            }
451
452
0
        default:
453
0
            return false;
454
4.47M
        }
455
4.47M
    } while (!stack.empty ());
456
457
    /* Check that nothing follows the initial construct (parsed above).  */
458
175k
    tok = getJsonToken(tokenVal, consumed, raw, end);
459
175k
    if (tok != JTOK_NONE)
460
13
        return false;
461
462
175k
    return true;
463
175k
}
464