README.md
1micro-ecc
2==========
3
4A small and fast ECDH and ECDSA implementation for 8-bit, 32-bit, and 64-bit processors.
5
6The old version of micro-ecc can be found in the "old" branch.
7
8Features
9--------
10
11 * Resistant to known side-channel attacks.
12 * Written in C, with optional GCC inline assembly for AVR, ARM and Thumb platforms.
13 * Supports 8, 32, and 64-bit architectures.
14 * Small code size.
15 * No dynamic memory allocation.
16 * Support for 5 standard curves: secp160r1, secp192r1, secp224r1, secp256r1, and secp256k1.
17 * BSD 2-clause license.
18
19Usage Notes
20-----------
21### Point Representation ###
22Compressed points are represented in the standard format as defined in http://www.secg.org/collateral/sec1_final.pdf; uncompressed points are represented in standard format, but without the `0x04` prefix. `uECC_make_key()`, `uECC_shared_secret()`, `uECC_sign()`, and `uECC_verify()` only handle uncompressed points; you can use `uECC_compress()` and `uECC_decompress()` to convert between compressed and uncompressed point representations.
23
24Private keys are represented in the standard format.
25
26### Using the Code ###
27
28I recommend just copying (or symlink) uECC.h, uECC.c, and the appropriate asm\_<arch>\_.inc (if any) into your project. Then just `#include "uECC.h"` to use the micro-ecc functions.
29
30For use with Arduino, you can just create a symlink to the `uECC` directory in your Arduino `libraries` directory. You can then use uECC just like any other Arduino library (uECC should show up in the **Sketch**=>**Import Library** submenu).
31
32See uECC.h for documentation for each function.
33
34### Compilation Notes ###
35
36 * Should compile with any C/C++ compiler that supports stdint.h (this includes Visual Studio 2013).
37 * If you want to change the defaults for `uECC_CURVE` and `uECC_ASM`, you must change them in your Makefile or similar so that uECC.c is compiled with the desired values (ie, compile uECC.c with `-DuECC_CURVE=uECC_secp256r1` or whatever).
38 * When compiling for a Thumb-1 platform with inline assembly enabled (ie, `uECC_ASM` is defined to `uECC_asm_small` or `uECC_asm_fast`), you must use the `-fomit-frame-pointer` GCC option (this is enabled by default when compiling with `-O1` or higher).
39 * When compiling for an ARM/Thumb-2 platform with fast inline assembly enabled (ie, `uECC_ASM` is defined to `uECC_asm_fast`), you must use the `-fomit-frame-pointer` GCC option (this is enabled by default when compiling with `-O1` or higher).
40 * When compiling for AVR with inline assembly enabled, you must have optimizations enabled (compile with `-O1` or higher).
41 * When building for Windows, you will need to link in the `advapi32.lib` system library.
42
43ARM Performance
44---------------
45
46All tests were built using gcc 4.8.2 with `-O3`, and were run on a Raspberry Pi B+. `uECC_ASM` was defined to `uECC_asm_fast` and `ECC_SQUARE_FUNC` was defined to `1` in all cases. All times are in milliseconds.
47
48<table>
49 <tr>
50 <th></th>
51 <th>secp160r1</th>
52 <th>secp192r1</th>
53 <th>secp256r1</th>
54 <th>secp256k1</th>
55 </tr>
56 <tr>
57 <td><em>ECDH:</em></td>
58 <td>2.3</td>
59 <td>2.7</td>
60 <td>7.9</td>
61 <td>6.5</td>
62 </tr>
63 <tr>
64 <td><em>ECDSA sign:</em></td>
65 <td>2.8</td>
66 <td>3.1</td>
67 <td>8.6</td>
68 <td>7.2</td>
69 </tr>
70 <tr>
71 <td><em>ECDSA verify:</em></td>
72 <td>2.7</td>
73 <td>3.2</td>
74 <td>9.2</td>
75 <td>7.0</td>
76 </tr>
77</table>
78
79AVR Performance
80---------------
81
82All tests were built using avr-gcc 4.8.1 with `-Os`, and were run on a 16 MHz ATmega256RFR2. Code size refers to the space used by micro-ecc code and data.
83
84#### ECDH (fast) ####
85
86In these tests, `uECC_ASM` was defined to `uECC_asm_fast` and `ECC_SQUARE_FUNC` was defined to `1` in all cases.
87
88<table>
89 <tr>
90 <th></th>
91 <th>secp160r1</th>
92 <th>secp192r1</th>
93 <th>secp256r1</th>
94 <th>secp256k1</th>
95 </tr>
96 <tr>
97 <td><em>ECDH time (ms):</em></td>
98 <td>470</td>
99 <td>810</td>
100 <td>2220</td>
101 <td>1615</td>
102 </tr>
103 <tr>
104 <td><em>Code size (bytes):</em></td>
105 <td>10768</td>
106 <td>13112</td>
107 <td>20886</td>
108 <td>21126</td>
109 </tr>
110</table>
111
112#### ECDH (small) ####
113
114In these tests, `uECC_ASM` was defined to `uECC_asm_small` and `ECC_SQUARE_FUNC` was defined to `0` in all cases.
115
116<table>
117 <tr>
118 <th></th>
119 <th>secp160r1</th>
120 <th>secp192r1</th>
121 <th>secp256r1</th>
122 <th>secp256k1</th>
123 </tr>
124 <tr>
125 <td><em>ECDH time (ms):</em></td>
126 <td>1250</td>
127 <td>1810</td>
128 <td>4790</td>
129 <td>4700</td>
130 </tr>
131 <tr>
132 <td><em>Code size (bytes):</em></td>
133 <td>3244</td>
134 <td>3400</td>
135 <td>5274</td>
136 <td>3426</td>
137 </tr>
138</table>
139
140#### ECDSA (fast) ####
141
142In these tests, `uECC_ASM` was defined to `uECC_asm_fast` and `ECC_SQUARE_FUNC` was defined to `1` in all cases.
143
144<table>
145 <tr>
146 <th></th>
147 <th>secp160r1</th>
148 <th>secp192r1</th>
149 <th>secp256r1</th>
150 <th>secp256k1</th>
151 </tr>
152 <tr>
153 <td><em>ECDSA sign time (ms):</em></td>
154 <td>555</td>
155 <td>902</td>
156 <td>2386</td>
157 <td>1773</td>
158 </tr>
159 <tr>
160 <td><em>ECDSA verify time (ms):</em></td>
161 <td>590</td>
162 <td>990</td>
163 <td>2650</td>
164 <td>1800</td>
165 </tr>
166 <tr>
167 <td><em>Code size (bytes):</em></td>
168 <td>13246</td>
169 <td>14798</td>
170 <td>22594</td>
171 <td>22826</td>
172 </tr>
173</table>
174
175#### ECDSA (small) ####
176
177In these tests, `uECC_ASM` was defined to `uECC_asm_small` and `ECC_SQUARE_FUNC` was defined to `0` in all cases.
178
179<table>
180 <tr>
181 <th></th>
182 <th>secp160r1</th>
183 <th>secp192r1</th>
184 <th>secp256r1</th>
185 <th>secp256k1</th>
186 </tr>
187 <tr>
188 <td><em>ECDSA sign time (ms):</em></td>
189 <td>1359</td>
190 <td>1931</td>
191 <td>4998</td>
192 <td>4904</td>
193 </tr>
194 <tr>
195 <td><em>ECDSA verify time (ms):</em></td>
196 <td>1515</td>
197 <td>2160</td>
198 <td>5700</td>
199 <td>5220</td>
200 </tr>
201 <tr>
202 <td><em>Code size (bytes):</em></td>
203 <td>5690</td>
204 <td>5054</td>
205 <td>6980</td>
206 <td>5080</td>
207 </tr>
208</table>
209