Toolbox for Key Space Testing of RHCS. Toolbox for Key Space Testing of Robust Hyper-Chaotic System

Transcription

1 Toolbox for Key Space Testing of Robust Hyper-Chaotic System

2 Toolbox for Key Space Testing of Robust Hyper-Chaotic System Content: I. Introduction.. 2 II. Parameter Interface III. SP Interface 9 IV. The Output Files V. Executable File Description

3 I. Introduction The output sequence of Robust Hyper-Chaotic System (RHCS) [1] is non-periodic and non-converging. The sequence can be used as the mask to encrypt plaintext. In other words, the cryptograph system is similar to a one-time-pad block cipher. In this case, the randomness of the key sequence directly affects the secure level of the system. In RHCS, parameters are including r and C. It is difficult to test the parameters one by one manually. This toolbox is designed for automatically creating parameters for RHCS to generate the masking sequences and to test the randomness by statistical methods. The toolbox combines the RHCS for masking sequence generation and the NIST SP [2] random number testing package, STS, for statistic analysis into an integrated tool with graphic user interface. A. Flow of Testing Parameter Setting RHCS Parameter Creating STS Result for current Parameters Final value? Final Result B. Main functions of toolbox 1. Masking stream generation by customized parameters. 2. Parameter strength analysis by automatic incremental parameter value. 3. Up to 15 testing items are included in SP testing package. C. System Requirement Minimum System Requirements Windows System XP OS: Intel Pentium III 800 MHz or AMD Athlon 800 MHz 256 MB or more of RAM 1 GB available HD space -2-

4 II. Parameter Interface A. Parameters Setting Page Toolbox for Key Space Testing of RHCS The main page is designed for a system that coupled by two robust logistic maps (n=2) in default. When user want to test the system with more than 2 coupled maps, the parameters file input is used. The main page is combined with followed sections. 1. Generator Parameters and Initial Values. 2. Space Scan of Parameters and Initial values. 3. Masking Stream Setting. 4. Parameter File. 5. Status. -3-

5 B. Generator Parameters and Initial Values. This section will set the parameters and initial values of the system. All fields are presented in hexadecimal format. Parameters r1 and r2 are separated in two parts, the fixed part and floating part. The basic input unit of all fields is two-hex digit, which is one byte. The input string 1AB in the fixed-point part will be extended to 01AB and input string 9AF12 in floating-point part will be extended to 9AF120 automatically. Length(x) means the length of x in half-byte. If x = , Length(x) = 4. For example, r= , Length(r) = Field Name Description Format Notes 1 r1 Parameter r 1 for robust_logistic_map 1 Hex Length(r1) = Length(r2) 2 r2 Parameter r 2 for robust_logistic_map 2 Hex Length(r1) = Length(r2) 3 c11 Parameter c 11 for robust_logistic_map 1 Hex All Length of c should be equal to each other. 4 c21 Parameter c 21 for robust_logistic_map 1 Hex Length(c) = Length(x1) 5 c12 Parameter c 12 for robust_logistic_map 2 Hex c11+ c12 = c22 Parameter c 22 for robust_logistic_map 2 Hex c21+ c22 = x1 Initial value of robust_logistic_map 1 Hex The system precision is decided by Length(x1). 8 x2 Initial value of robust_logistic_map 2 Hex Length(x1) = Length(x2) All parameters have the same length are recommended. -4-

6 Example: The parameters of system will be: r 1 = r 2 = ab c 11 = 0.23ad01bf c 12 = 0.dc52fe41 c 21 = c 22 = 0.ff98e679 x 1 = fd3f x 2 = 0.443f8592 C. Space Scan of Parameters and Initial values. This section will set the scan target and scale of the parameters or initial values. The base value of target is set by previous section. The toolbox generates the output streams for each step of parameters and performs the statistic analysis Field Name Description Format Notes 1 r1 To select r 1 for space scan 1/0 Only one target 2 r2 To select r 2 for space scan 1/0 is selected in 3 x1 To select x 1 for space scan 1/0 parameter scan 4 x2 To select x 2 for space scan 1/0 5 Stride The number of stride of space scan Hex Default is 1 6 Grid The incremental size. It will be added into target parameter in each stride. Hex Default is 1-5-

7 Example: By these setting, if r1 = from r1 = to FF, there are 255 masking sequences with other parameters are fixed will be generated and tested. C. Masking Stream Setting. This section will set the output range of the masking stream of the system. User can decide to drop how many bytes from the head of streams and rear of streams Field Name Description Format 1 Head dropping Number of Bytes will be drop from head of stream Dec 2 Rear dropping Number of Bytes will be drop from rear of stream Dec 3 Total Number Total Number of Streams will be generated of Streams Dec -6-

8 Example: If Length(x1) = 10, The Length(output stream) = Length(x1) (Head Dropping + Rear Dropping) x 2 = 10 (2 + 1) x 2 = 4 Total half-bytes of output streams = 1000 x 4. D. Parameter File. Parameters can be read from input file. The example of input file of a testing system with n = 3 is as follow: 3 // the number of coupled maps (n=3) r 1 // scan parameter r1 1 2 // Gride = 1, Stride = 2 AA AA11 // r1 = AA.AA11 BB CC00 // r2 = BB.CC // r3 = FE // c11=0.fe00 c12=0.0100, c13= FE // c21=0.fe00 c22=0.0100, c23= FE // c31=0.fe00 c32=0.0100, c33= A02 // x1 = 0.5A02 BA00 // x2 = 0.BA00 1A12 // x3 = 0.1A // head dropping=0, read dropping=0, total 111 streams will be generated -7-

9 E. Status. The status area shows the current setting of the system. From above setting the status area is -8-

10 III. SP Interface After parameters setting page, the following page will be SP-800 testing page. For detailed description of SP testing package, please refer to the reference [1]. Please note it, total bytes of the generated masking stream should be enough for the STS testing requirement. -9-

11 IV. The Output Files The summary of the testing result is in result directory. The description is as follow: File Name result\finalresult result\para_list result\summary result\ Hyper-Chaotic_finalAnalysisReport_x Description Results for the uniformity of p-values and the proportion of pass sequences are shown in this file. The scan values of the target parameter. The proportion of each scan values is shown. For each scan value of target, all the FinalAnalysisReport files generated by STS are stored. -10-

12 V. Executable File Description The executable files description. Toolbox for Key Space Testing of RHCS Name File Size Description ToolBox.exe 778,325 bytes The main program of toolbox. gen_hex.exe 555,080 bytes The RHCS sequence generator. -11-

13 References [1] Random Number Generation and Testing, [2] S. L. Chen, S. M. Chang, T. T. Hwang and W. W. Lin, Digital Secure-Communication Using Robust Hyper-Chaotic Systems, NCTS Preprints Series in Taiwan, ( -12-

14 History Date Version Description Toolbox for Key Space Testing of RHCS It is a preliminary version for reference First Release. -13-