1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
|
/*
* SecureQueue
* (C) 1999-2007 Jack Lloyd
* 2012 Markus Wanner
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#include <botan/secqueue.h>
#include <algorithm>
namespace Botan {
/**
* A node in a SecureQueue
*/
class SecureQueueNode final
{
public:
SecureQueueNode() : m_buffer(BOTAN_DEFAULT_BUFFER_SIZE)
{ m_next = nullptr; m_start = m_end = 0; }
~SecureQueueNode() { m_next = nullptr; m_start = m_end = 0; }
size_t write(const uint8_t input[], size_t length)
{
size_t copied = std::min<size_t>(length, m_buffer.size() - m_end);
copy_mem(m_buffer.data() + m_end, input, copied);
m_end += copied;
return copied;
}
size_t read(uint8_t output[], size_t length)
{
size_t copied = std::min(length, m_end - m_start);
copy_mem(output, m_buffer.data() + m_start, copied);
m_start += copied;
return copied;
}
size_t peek(uint8_t output[], size_t length, size_t offset = 0)
{
const size_t left = m_end - m_start;
if(offset >= left) return 0;
size_t copied = std::min(length, left - offset);
copy_mem(output, m_buffer.data() + m_start + offset, copied);
return copied;
}
size_t size() const { return (m_end - m_start); }
private:
friend class SecureQueue;
SecureQueueNode* m_next;
secure_vector<uint8_t> m_buffer;
size_t m_start, m_end;
};
/*
* Create a SecureQueue
*/
SecureQueue::SecureQueue()
{
m_bytes_read = 0;
set_next(nullptr, 0);
m_head = m_tail = new SecureQueueNode;
}
/*
* Copy a SecureQueue
*/
SecureQueue::SecureQueue(const SecureQueue& input) :
Fanout_Filter(), DataSource()
{
m_bytes_read = 0;
set_next(nullptr, 0);
m_head = m_tail = new SecureQueueNode;
SecureQueueNode* temp = input.m_head;
while(temp)
{
write(&temp->m_buffer[temp->m_start], temp->m_end - temp->m_start);
temp = temp->m_next;
}
}
/*
* Destroy this SecureQueue
*/
void SecureQueue::destroy()
{
SecureQueueNode* temp = m_head;
while(temp)
{
SecureQueueNode* holder = temp->m_next;
delete temp;
temp = holder;
}
m_head = m_tail = nullptr;
}
/*
* Copy a SecureQueue
*/
SecureQueue& SecureQueue::operator=(const SecureQueue& input)
{
if(this == &input)
return *this;
destroy();
m_bytes_read = input.get_bytes_read();
m_head = m_tail = new SecureQueueNode;
SecureQueueNode* temp = input.m_head;
while(temp)
{
write(&temp->m_buffer[temp->m_start], temp->m_end - temp->m_start);
temp = temp->m_next;
}
return (*this);
}
/*
* Add some bytes to the queue
*/
void SecureQueue::write(const uint8_t input[], size_t length)
{
if(!m_head)
m_head = m_tail = new SecureQueueNode;
while(length)
{
const size_t n = m_tail->write(input, length);
input += n;
length -= n;
if(length)
{
m_tail->m_next = new SecureQueueNode;
m_tail = m_tail->m_next;
}
}
}
/*
* Read some bytes from the queue
*/
size_t SecureQueue::read(uint8_t output[], size_t length)
{
size_t got = 0;
while(length && m_head)
{
const size_t n = m_head->read(output, length);
output += n;
got += n;
length -= n;
if(m_head->size() == 0)
{
SecureQueueNode* holder = m_head->m_next;
delete m_head;
m_head = holder;
}
}
m_bytes_read += got;
return got;
}
/*
* Read data, but do not remove it from queue
*/
size_t SecureQueue::peek(uint8_t output[], size_t length, size_t offset) const
{
SecureQueueNode* current = m_head;
while(offset && current)
{
if(offset >= current->size())
{
offset -= current->size();
current = current->m_next;
}
else
break;
}
size_t got = 0;
while(length && current)
{
const size_t n = current->peek(output, length, offset);
offset = 0;
output += n;
got += n;
length -= n;
current = current->m_next;
}
return got;
}
/**
* Return how many bytes have been read so far.
*/
size_t SecureQueue::get_bytes_read() const
{
return m_bytes_read;
}
/*
* Return how many bytes the queue holds
*/
size_t SecureQueue::size() const
{
SecureQueueNode* current = m_head;
size_t count = 0;
while(current)
{
count += current->size();
current = current->m_next;
}
return count;
}
/*
* Test if the queue has any data in it
*/
bool SecureQueue::end_of_data() const
{
return (size() == 0);
}
bool SecureQueue::empty() const
{
return (size() == 0);
}
}
|
