/src/FreeRDP/channels/drdynvc/client/test/TestFuzzDrdynvc.c

Source
/**
 * FreeRDP: A Remote Desktop Protocol Implementation
 * libFuzzer harness for DVC wire framing
 */

#include <stddef.h>
#include <stdint.h>

#include <winpr/stream.h>
#include <winpr/wtypes.h>

static UINT32 fuzz_var_uint_bytes(UINT8 cbLen)
{
  switch (cbLen)
  {
    case 0:
      return 1;
    case 1:
      return 2;
    default:
      return 4;
  }
}

static UINT32 fuzz_read_variable_uint(wStream* s, UINT8 cbLen)
{
  UINT32 value = 0;

  switch (cbLen)
  {
    case 0:
      value = Stream_Get_UINT8(s);
      break;
    case 1:
      value = Stream_Get_UINT16(s);
      break;
    default:
      value = Stream_Get_UINT32(s);
      break;
  }

  return value;
}

enum
{
  CREATE_REQUEST_PDU = 0x01,
  DATA_FIRST_PDU = 0x02,
  DATA_PDU = 0x03,
  CLOSE_REQUEST_PDU = 0x04,
  CAPABILITY_REQUEST_PDU = 0x05,
  DATA_FIRST_COMPRESSED_PDU = 0x06,
  DATA_COMPRESSED_PDU = 0x07
};

static int fuzz_process_one_pdu(wStream* s)
{
  const size_t required = 1;

  if (!Stream_CheckAndLogRequiredLength("fuzz", s, required))
    return -1;

  UINT8 header = Stream_Get_UINT8(s);
  UINT8 command = (header & 0xf0) >> 4;
  UINT8 spacing = (header & 0x0c) >> 2;
  UINT8 cbChId = (header & 0x03);
  size_t needed = fuzz_var_uint_bytes(cbChId);

  switch (command)
  {
    case DATA_FIRST_PDU:
    case DATA_FIRST_COMPRESSED_PDU:
      if (!Stream_CheckAndLogRequiredLength("fuzz", s, needed + fuzz_var_uint_bytes(spacing)))
        return -1;
      (void)fuzz_read_variable_uint(s, cbChId);
      (void)fuzz_read_variable_uint(s, spacing);
      break;
    case DATA_PDU:
    case DATA_COMPRESSED_PDU:
    case CLOSE_REQUEST_PDU:
    case CREATE_REQUEST_PDU:
      if (!Stream_CheckAndLogRequiredLength("fuzz", s, needed))
        return -1;
      (void)fuzz_read_variable_uint(s, cbChId);
      break;
    case CAPABILITY_REQUEST_PDU:
      if (!Stream_CheckAndLogRequiredLength("fuzz", s, 2))
        return -1;
      Stream_Seek(s, 2);
      break;
    default:
      break;
  }

  if (!Stream_CheckAndLogRequiredLength("fuzz", s, 2))
    return -1;

  {
    size_t bodyLen = Stream_Get_UINT16(s);
    const size_t remaining = Stream_GetRemainingLength(s);
    if (bodyLen > remaining)
      bodyLen = remaining;
    Stream_Seek(s, bodyLen);
  }

  return 0;
}

int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size)
{
  if ((size == 0) || (size > (1u << 20)))
    return 0;

  wStream* s = Stream_New((BYTE*)data, size);
  if (!s)
    return 0;

  for (size_t index = 0; index < 64; index++)
  {
    if (Stream_GetRemainingLength(s) == 0)
      break;
    if (fuzz_process_one_pdu(s) != 0)
      break;
  }

  Stream_Free(s, FALSE);
  return 0;
}

Line	Count	Source
1		/**
2		* FreeRDP: A Remote Desktop Protocol Implementation
3		* libFuzzer harness for DVC wire framing
4		*/
5
6		#include <stddef.h>
7		#include <stdint.h>
8
9		#include <winpr/stream.h>
10		#include <winpr/wtypes.h>
11
12		static UINT32 fuzz_var_uint_bytes(UINT8 cbLen)
13	9.30k	{
14	9.30k	switch (cbLen)
15	9.30k	{
16	5.42k	case 0:
17	5.42k	return 1;
18	1.57k	case 1:
19	1.57k	return 2;
20	2.30k	default:
21	2.30k	return 4;
22	9.30k	}
23	9.30k	}
24
25		static UINT32 fuzz_read_variable_uint(wStream* s, UINT8 cbLen)
26	5.90k	{
27	5.90k	UINT32 value = 0;
28
29	5.90k	switch (cbLen)
30	5.90k	{
31	2.50k	case 0:
32	2.50k	value = Stream_Get_UINT8(s);
33	2.50k	break;
34	1.44k	case 1:
35	1.44k	value = Stream_Get_UINT16(s);
36	1.44k	break;
37	1.95k	default:
38	1.95k	value = Stream_Get_UINT32(s);
39	1.95k	break;
40	5.90k	}
41
42	5.90k	return value;
43	5.90k	}
44
45		enum
46		{
47		CREATE_REQUEST_PDU = 0x01,
48		DATA_FIRST_PDU = 0x02,
49		DATA_PDU = 0x03,
50		CLOSE_REQUEST_PDU = 0x04,
51		CAPABILITY_REQUEST_PDU = 0x05,
52		DATA_FIRST_COMPRESSED_PDU = 0x06,
53		DATA_COMPRESSED_PDU = 0x07
54		};
55
56		static int fuzz_process_one_pdu(wStream* s)
57	7.59k	{
58	7.59k	const size_t required = 1;
59
60	7.59k	if (!Stream_CheckAndLogRequiredLength("fuzz", s, required))
61	0	return -1;
62
63	7.59k	UINT8 header = Stream_Get_UINT8(s);
64	7.59k	UINT8 command = (header & 0xf0) >> 4;
65	7.59k	UINT8 spacing = (header & 0x0c) >> 2;
66	7.59k	UINT8 cbChId = (header & 0x03);
67	7.59k	size_t needed = fuzz_var_uint_bytes(cbChId);
68
69	7.59k	switch (command)
70	7.59k	{
71	816	case DATA_FIRST_PDU:
72	1.71k	case DATA_FIRST_COMPRESSED_PDU:
73	1.71k	if (!Stream_CheckAndLogRequiredLength("fuzz", s, needed + fuzz_var_uint_bytes(spacing)))
74	28	return -1;
75	1.68k	(void)fuzz_read_variable_uint(s, cbChId);
76	1.68k	(void)fuzz_read_variable_uint(s, spacing);
77	1.68k	break;
78	600	case DATA_PDU:
79	1.36k	case DATA_COMPRESSED_PDU:
80	2.02k	case CLOSE_REQUEST_PDU:
81	2.58k	case CREATE_REQUEST_PDU:
82	2.58k	if (!Stream_CheckAndLogRequiredLength("fuzz", s, needed))
83	48	return -1;
84	2.53k	(void)fuzz_read_variable_uint(s, cbChId);
85	2.53k	break;
86	196	case CAPABILITY_REQUEST_PDU:
87	196	if (!Stream_CheckAndLogRequiredLength("fuzz", s, 2))
88	4	return -1;
89	192	Stream_Seek(s, 2);
90	192	break;
91	3.10k	default:
92	3.10k	break;
93	7.59k	}
94
95	7.51k	if (!Stream_CheckAndLogRequiredLength("fuzz", s, 2))
96	107	return -1;
97
98	7.40k	{
99	7.40k	size_t bodyLen = Stream_Get_UINT16(s);
100	7.40k	const size_t remaining = Stream_GetRemainingLength(s);
101	7.40k	if (bodyLen > remaining)
102	180	bodyLen = remaining;
103	7.40k	Stream_Seek(s, bodyLen);
104	7.40k	}
105
106	7.40k	return 0;
107	7.51k	}
108
109		int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size)
110	419	{
111	419	if ((size == 0) \|\| (size > (1u << 20)))
112	0	return 0;
113
114	419	wStream* s = Stream_New((BYTE*)data, size);
115	419	if (!s)
116	0	return 0;
117
118	7.82k	for (size_t index = 0; index < 64; index++)
119	7.78k	{
120	7.78k	if (Stream_GetRemainingLength(s) == 0)
121	193	break;
122	7.59k	if (fuzz_process_one_pdu(s) != 0)
123	187	break;
124	7.59k	}
125
126	419	Stream_Free(s, FALSE);
127	419	return 0;
128	419	}

Coverage Report

Created: 2026-05-30 06:41