randombit/botan | Build 13274522654 | source/src/lib/modes/cfb/cfb.cpp | Coveralls

16

CFB_Mode::CFB_Mode(std::unique_ptr<BlockCipher> cipher, size_t feedback_bits) :

705✔

17

      m_cipher(std::move(cipher)),

705✔

18

      m_block_size(m_cipher->block_size()),

705✔

19

      m_feedback_bytes(feedback_bits ? feedback_bits / 8 : m_block_size) {

705✔

20

   if(feedback_bits % 8 || feedback() > m_block_size) {

705✔

23

705✔

25

void CFB_Mode::clear() {

158✔

26

   m_cipher->clear();

158✔

27

   m_keystream.clear();

158✔

28

   reset();

158✔

29

158✔

31

void CFB_Mode::reset() {

474✔

32

   m_state.clear();

474✔

33

   zeroise(m_keystream);

474✔

34

474✔

36

std::string CFB_Mode::name() const {

948✔

37

   if(feedback() == cipher().block_size()) {

948✔

38

      return fmt("{}/CFB", cipher().name());

396✔

40

      return fmt("{}/CFB({})", cipher().name(), feedback() * 8);

552✔

44

size_t CFB_Mode::output_length(size_t input_length) const {

158✔

45

   return input_length;

158✔

48

size_t CFB_Mode::update_granularity() const {

553✔

49

   return feedback();

553✔

52

size_t CFB_Mode::ideal_granularity() const {

478✔

54

   return 16 * feedback();

478✔

57

size_t CFB_Mode::minimum_final_size() const {

160✔

58

   return 0;

160✔

61

Key_Length_Specification CFB_Mode::key_spec() const {

1,090✔

62

   return cipher().key_spec();

1,090✔

65

size_t CFB_Mode::default_nonce_length() const {

466✔

66

   return block_size();

466✔

69

bool CFB_Mode::valid_nonce_length(size_t n) const {

1,880✔

70

   return (n == 0 || n == block_size());

1,850✔

73

bool CFB_Mode::has_keying_material() const {

5,042✔

74

   return m_cipher->has_keying_material();

5,042✔

77

void CFB_Mode::key_schedule(std::span<const uint8_t> key) {

784✔

78

   m_cipher->set_key(key);

784✔

79

   m_keystream.resize(m_cipher->block_size());

784✔

80

784✔

82

void CFB_Mode::start_msg(const uint8_t nonce[], size_t nonce_len) {

1,538✔

83

   if(!valid_nonce_length(nonce_len)) {

1,538✔

84

      throw Invalid_IV_Length(name(), nonce_len);

316✔

87

   assert_key_material_set();

1,380✔

89

   if(nonce_len == 0) {

1,380✔

90

      if(m_state.empty()) {

30✔

95

      m_state.assign(nonce, nonce + nonce_len);

1,350✔

96

      cipher().encrypt(m_state, m_keystream);

1,350✔

97

      m_keystream_pos = 0;

1,350✔

99

1,380✔

101

void CFB_Mode::shift_register() {

6,413✔

102

   const size_t shift = feedback();

6,413✔

103

   const size_t carryover = block_size() - shift;

6,413✔

105

   if(carryover > 0) {

6,413✔

106

      copy_mem(m_state.data(), &m_state[shift], carryover);

3,104✔

108

   copy_mem(&m_state[carryover], m_keystream.data(), shift);

6,413✔

109

   cipher().encrypt(m_state, m_keystream);

6,413✔

110

   m_keystream_pos = 0;

6,413✔

111

6,413✔

113

size_t CFB_Encryption::process_msg(uint8_t buf[], size_t sz) {

1,542✔

114

   assert_key_material_set();

1,542✔

115

   BOTAN_STATE_CHECK(m_state.empty() == false);

1,226✔

117

   const size_t shift = feedback();

1,068✔

119

   size_t left = sz;

1,068✔

121

   if(m_keystream_pos != 0) {

1,068✔

122

      const size_t take = std::min<size_t>(left, shift - m_keystream_pos);

13✔

124

      xor_buf(m_keystream.data() + m_keystream_pos, buf, take);

13✔

125

      copy_mem(buf, m_keystream.data() + m_keystream_pos, take);

13✔

127

      m_keystream_pos += take;

13✔

128

      left -= take;

13✔

129

      buf += take;

13✔

131

      if(m_keystream_pos == shift) {

13✔

132

         shift_register();

10✔

136

   while(left >= shift) {

3,757✔

137

      xor_buf(m_keystream.data(), buf, shift);

2,689✔

138

      copy_mem(buf, m_keystream.data(), shift);

2,689✔

140

      left -= shift;

2,689✔

141

      buf += shift;

2,689✔

142

      shift_register();

2,689✔

145

   if(left > 0) {

1,068✔

146

      xor_buf(m_keystream.data(), buf, left);

118✔

147

      copy_mem(buf, m_keystream.data(), left);

118✔

148

      m_keystream_pos += left;

118✔

151

   return sz;

1,068✔

154

void CFB_Encryption::finish_msg(secure_vector<uint8_t>& buffer, size_t offset) {

616✔

155

   update(buffer, offset);

616✔

156

379✔

160

inline void xor_copy(uint8_t buf[], uint8_t key_buf[], size_t len) {

3,943✔

161

   for(size_t i = 0; i != len; ++i) {

40,400✔

162

      uint8_t k = key_buf[i];

36,457✔

163

      key_buf[i] = buf[i];

36,457✔

164

      buf[i] ^= k;

36,457✔

170

size_t CFB_Decryption::process_msg(uint8_t buf[], size_t sz) {

1,646✔

171

   assert_key_material_set();

1,646✔

172

   BOTAN_STATE_CHECK(m_state.empty() == false);

1,330✔

174

   const size_t shift = feedback();

1,172✔

176

   size_t left = sz;

1,172✔

178

   if(m_keystream_pos != 0) {

1,172✔

179

      const size_t take = std::min<size_t>(left, shift - m_keystream_pos);

13✔

181

      xor_copy(buf, m_keystream.data() + m_keystream_pos, take);

13✔

183

      m_keystream_pos += take;

13✔

184

      left -= take;

13✔

185

      buf += take;

13✔

187

      if(m_keystream_pos == shift) {

13✔

188

         shift_register();

10✔

192

   while(left >= shift) {

4,876✔

193

      xor_copy(buf, m_keystream.data(), shift);

3,704✔

194

      left -= shift;

3,704✔

195

      buf += shift;

3,704✔

196

      shift_register();

3,704✔

199

   if(left > 0) {

1,172✔

200

      xor_copy(buf, m_keystream.data(), left);

226✔

201

      m_keystream_pos += left;

226✔

204

   return sz;

1,172✔

207

void CFB_Decryption::finish_msg(secure_vector<uint8_t>& buffer, size_t offset) {

616✔

208

   update(buffer, offset);

616✔

209

379✔

randombit / botan / 13274522654

Source File
Press 'n' to go to next uncovered line, 'b' for previous

1	/*
2	* CFB Mode
3	* (C) 1999-2007,2013,2017 Jack Lloyd
4	* (C) 2016 Daniel Neus, Rohde & Schwarz Cybersecurity
5	*
6	* Botan is released under the Simplified BSD License (see license.txt)
7	*/
8
9	#include <botan/internal/cfb.h>
10
11	#include <botan/mem_ops.h>
12	#include <botan/internal/fmt.h>
13
14	namespace Botan {
15
16	CFB_Mode::CFB_Mode(std::unique_ptr<BlockCipher> cipher, size_t feedback_bits) :	705✔
17	m_cipher(std::move(cipher)),	705✔
18	m_block_size(m_cipher->block_size()),	705✔
19	m_feedback_bytes(feedback_bits ? feedback_bits / 8 : m_block_size) {	705✔
20	if(feedback_bits % 8 \|\| feedback() > m_block_size) {	705✔
21	throw Invalid_Argument(fmt("{} does not support feedback bits of {}", name(), feedback_bits));	×
22	}
23	}	705✔
24
25	void CFB_Mode::clear() {	158✔
26	m_cipher->clear();	158✔
27	m_keystream.clear();	158✔
28	reset();	158✔
29	}	158✔
30
31	void CFB_Mode::reset() {	474✔
32	m_state.clear();	474✔
33	zeroise(m_keystream);	474✔
34	}	474✔
35
36	std::string CFB_Mode::name() const {	948✔
37	if(feedback() == cipher().block_size()) {	948✔
38	return fmt("{}/CFB", cipher().name());	396✔
39	} else {
40	return fmt("{}/CFB({})", cipher().name(), feedback() * 8);	552✔
41	}
42	}
43
44	size_t CFB_Mode::output_length(size_t input_length) const {	158✔
45	return input_length;	158✔
46	}
47
48	size_t CFB_Mode::update_granularity() const {	553✔
49	return feedback();	553✔
50	}
51
52	size_t CFB_Mode::ideal_granularity() const {	478✔
53	// Multiplier here is arbitrary
54	return 16 * feedback();	478✔
55	}
56
57	size_t CFB_Mode::minimum_final_size() const {	160✔
58	return 0;	160✔
59	}
60
61	Key_Length_Specification CFB_Mode::key_spec() const {	1,090✔
62	return cipher().key_spec();	1,090✔
63	}
64
65	size_t CFB_Mode::default_nonce_length() const {	466✔
66	return block_size();	466✔
67	}
68
69	bool CFB_Mode::valid_nonce_length(size_t n) const {	1,880✔
70	return (n == 0 \|\| n == block_size());	1,850✔
71	}
72
73	bool CFB_Mode::has_keying_material() const {	5,042✔
74	return m_cipher->has_keying_material();	5,042✔
75	}
76
77	void CFB_Mode::key_schedule(std::span<const uint8_t> key) {	784✔
78	m_cipher->set_key(key);	784✔
79	m_keystream.resize(m_cipher->block_size());	784✔
80	}	784✔
81
82	void CFB_Mode::start_msg(const uint8_t nonce[], size_t nonce_len) {	1,538✔
83	if(!valid_nonce_length(nonce_len)) {	1,538✔
84	throw Invalid_IV_Length(name(), nonce_len);	316✔
85	}
86
87	assert_key_material_set();	1,380✔
88
89	if(nonce_len == 0) {	1,380✔
90	if(m_state.empty()) {	30✔
91	throw Invalid_State("CFB requires a non-empty initial nonce");	×
92	}
93	// No reason to encrypt state->keystream_buf, because no change
94	} else {
95	m_state.assign(nonce, nonce + nonce_len);	1,350✔
96	cipher().encrypt(m_state, m_keystream);	1,350✔
97	m_keystream_pos = 0;	1,350✔
98	}
99	}	1,380✔
100
101	void CFB_Mode::shift_register() {	6,413✔
102	const size_t shift = feedback();	6,413✔
103	const size_t carryover = block_size() - shift;	6,413✔
104
105	if(carryover > 0) {	6,413✔
106	copy_mem(m_state.data(), &m_state[shift], carryover);	3,104✔
107	}
108	copy_mem(&m_state[carryover], m_keystream.data(), shift);	6,413✔
109	cipher().encrypt(m_state, m_keystream);	6,413✔
110	m_keystream_pos = 0;	6,413✔
111	}	6,413✔
112
113	size_t CFB_Encryption::process_msg(uint8_t buf[], size_t sz) {	1,542✔
114	assert_key_material_set();	1,542✔
115	BOTAN_STATE_CHECK(m_state.empty() == false);	1,226✔
116
117	const size_t shift = feedback();	1,068✔
118
119	size_t left = sz;	1,068✔
120
121	if(m_keystream_pos != 0) {	1,068✔
122	const size_t take = std::min<size_t>(left, shift - m_keystream_pos);	13✔
123
124	xor_buf(m_keystream.data() + m_keystream_pos, buf, take);	13✔
125	copy_mem(buf, m_keystream.data() + m_keystream_pos, take);	13✔
126
127	m_keystream_pos += take;	13✔
128	left -= take;	13✔
129	buf += take;	13✔
130
131	if(m_keystream_pos == shift) {	13✔
132	shift_register();	10✔
133	}
134	}
135
136	while(left >= shift) {	3,757✔
137	xor_buf(m_keystream.data(), buf, shift);	2,689✔
138	copy_mem(buf, m_keystream.data(), shift);	2,689✔
139
140	left -= shift;	2,689✔
141	buf += shift;	2,689✔
142	shift_register();	2,689✔
143	}
144
145	if(left > 0) {	1,068✔
146	xor_buf(m_keystream.data(), buf, left);	118✔
147	copy_mem(buf, m_keystream.data(), left);	118✔
148	m_keystream_pos += left;	118✔
149	}
150
151	return sz;	1,068✔
152	}
153
154	void CFB_Encryption::finish_msg(secure_vector<uint8_t>& buffer, size_t offset) {	616✔
155	update(buffer, offset);	616✔
156	}	379✔
157
158	namespace {
159
160	inline void xor_copy(uint8_t buf[], uint8_t key_buf[], size_t len) {	3,943✔
161	for(size_t i = 0; i != len; ++i) {	40,400✔
162	uint8_t k = key_buf[i];	36,457✔
163	key_buf[i] = buf[i];	36,457✔
164	buf[i] ^= k;	36,457✔
165	}
166	}
167
168	} // namespace
169
170	size_t CFB_Decryption::process_msg(uint8_t buf[], size_t sz) {	1,646✔
171	assert_key_material_set();	1,646✔
172	BOTAN_STATE_CHECK(m_state.empty() == false);	1,330✔
173
174	const size_t shift = feedback();	1,172✔
175
176	size_t left = sz;	1,172✔
177
178	if(m_keystream_pos != 0) {	1,172✔
179	const size_t take = std::min<size_t>(left, shift - m_keystream_pos);	13✔
180
181	xor_copy(buf, m_keystream.data() + m_keystream_pos, take);	13✔
182
183	m_keystream_pos += take;	13✔
184	left -= take;	13✔
185	buf += take;	13✔
186
187	if(m_keystream_pos == shift) {	13✔
188	shift_register();	10✔
189	}
190	}
191
192	while(left >= shift) {	4,876✔
193	xor_copy(buf, m_keystream.data(), shift);	3,704✔
194	left -= shift;	3,704✔
195	buf += shift;	3,704✔
196	shift_register();	3,704✔
197	}
198
199	if(left > 0) {	1,172✔
200	xor_copy(buf, m_keystream.data(), left);	226✔
201	m_keystream_pos += left;	226✔
202	}
203
204	return sz;	1,172✔
205	}
206
207	void CFB_Decryption::finish_msg(secure_vector<uint8_t>& buffer, size_t offset) {	616✔
208	update(buffer, offset);	616✔
209	}	379✔
210
211	} // namespace Botan

randombit / botan / 13274522654

Source File Press 'n' to go to next uncovered line, 'b' for previous

Source File
Press 'n' to go to next uncovered line, 'b' for previous