Arduino Cryptography Library
OFB.h
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22 
23 #ifndef CRYPTO_OFB_h
24 #define CRYPTO_OFB_h
25 
26 #include "Cipher.h"
27 #include "BlockCipher.h"
28 
29 class OFBCommon : public Cipher
30 {
31 public:
32  virtual ~OFBCommon();
33 
34  size_t keySize() const;
35  size_t ivSize() const;
36 
37  bool setKey(const uint8_t *key, size_t len);
38  bool setIV(const uint8_t *iv, size_t len);
39 
40  void encrypt(uint8_t *output, const uint8_t *input, size_t len);
41  void decrypt(uint8_t *output, const uint8_t *input, size_t len);
42 
43  void clear();
44 
45 protected:
46  OFBCommon();
47  void setBlockCipher(BlockCipher *cipher) { blockCipher = cipher; }
48 
49 private:
50  BlockCipher *blockCipher;
51  uint8_t iv[16];
52  uint8_t posn;
53 };
54 
55 template <typename T>
56 class OFB : public OFBCommon
57 {
58 public:
59  OFB() { setBlockCipher(&cipher); }
60 
61 private:
62  T cipher;
63 };
64 
65 #endif
Abstract base class for block ciphers.
Definition: BlockCipher.h:30
Abstract base class for stream ciphers.
Definition: Cipher.h:30
Concrete base class to assist with implementing OFB for 128-bit block ciphers.
Definition: OFB.h:30
void setBlockCipher(BlockCipher *cipher)
Sets the block cipher to use for this OFB object.
Definition: OFB.h:47
size_t keySize() const
Default size of the key for this cipher, in bytes.
Definition: OFB.cpp:56
bool setIV(const uint8_t *iv, size_t len)
Sets the initialization vector to use for future encryption and decryption operations.
Definition: OFB.cpp:76
void clear()
Clears all security-sensitive state from this cipher.
Definition: OFB.cpp:113
OFBCommon()
Constructs a new cipher in OFB mode.
Definition: OFB.cpp:42
void encrypt(uint8_t *output, const uint8_t *input, size_t len)
Encrypts an input buffer and writes the ciphertext to an output buffer.
Definition: OFB.cpp:85
size_t ivSize() const
Size of the initialization vector for this cipher, in bytes.
Definition: OFB.cpp:61
virtual ~OFBCommon()
Destroys this cipher object after clearing sensitive information.
Definition: OFB.cpp:51
bool setKey(const uint8_t *key, size_t len)
Sets the key to use for future encryption and decryption operations.
Definition: OFB.cpp:66
void decrypt(uint8_t *output, const uint8_t *input, size_t len)
Decrypts an input buffer and writes the plaintext to an output buffer.
Definition: OFB.cpp:108
Implementation of the Output Feedback (OFB) mode for 128-bit block ciphers.
Definition: OFB.h:57
OFB()
Constructs a new OFB object for the block cipher T.
Definition: OFB.h:59