libsecp256k1 库编译+jni库编译--bitcoin

梦里梦外; 2022-06-01 12:45 498阅读 0赞

原文：[https://github.com/bitcoin-core/secp256k1][https_github.com_bitcoin-core_secp256k1]

先下载源文件。

以下是摘抄：

Optimized C library for EC operations on curve secp256k1.

This library is a work in progress and is being used to research best practices. Use at your own risk.

Features:

*  secp256k1 ECDSA signing/verification and key generation.
 *  Adding/multiplying private/public keys.
 *  Serialization/parsing of private keys, public keys, signatures.
 *  Constant time, constant memory access signing and pubkey generation.
 *  Derandomized DSA (via RFC6979 or with a caller provided function.)
 *  Very efficient implementation.

## Implementation details ##

*  General
    
     *  No runtime heap allocation.
     *  Extensive testing infrastructure.
     *  Structured to facilitate review and analysis.
     *  Intended to be portable to any system with a C89 compiler and uint64\_t support.
     *  Expose only higher level interfaces to minimize the API surface and improve application security. ("Be difficult to use insecurely.")
 *  Field operations
    
     *  Optimized implementation of arithmetic modulo the curve's field size (2^256 - 0x1000003D1).
        
         *  Using 5 52-bit limbs (including hand-optimized assembly for x86\_64, by Diederik Huys).
         *  Using 10 26-bit limbs.
     *  Field inverses and square roots using a sliding window over blocks of 1s (by Peter Dettman).
 *  Scalar operations
    
     *  Optimized implementation without data-dependent branches of arithmetic modulo the curve's order.
        
         *  Using 4 64-bit limbs (relying on \_\_int128 support in the compiler).
         *  Using 8 32-bit limbs.
 *  Group operations
    
     *  Point addition formula specifically simplified for the curve equation (y^2 = x^3 + 7).
     *  Use addition between points in Jacobian and affine coordinates where possible.
     *  Use a unified addition/doubling formula where necessary to avoid data-dependent branches.
     *  Point/x comparison without a field inversion by comparison in the Jacobian coordinate space.
 *  Point multiplication for verification (a*P + b*G).
    
     *  Use wNAF notation for point multiplicands.
     *  Use a much larger window for multiples of G, using precomputed multiples.
     *  Use Shamir's trick to do the multiplication with the public key and the generator simultaneously.
     *  Optionally (off by default) use secp256k1's efficiently-computable endomorphism to split the P multiplicand into 2 half-sized ones.
 *  Point multiplication for signing
    
     *  Use a precomputed table of multiples of powers of 16 multiplied with the generator, so general multiplication becomes a series of additions.
     *  Access the table with branch-free conditional moves so memory access is uniform.
     *  No data-dependent branches
     *  The precomputed tables add and eventually subtract points for which no known scalar (private key) is known, preventing even an attacker with control over the private key used to control the data internally.

## Linux Build steps ##

libsecp256k1 is built using autotools:

./autogen.sh
    ./configure
    make
    ./tests
    sudo make install  # optional

上面是编译标准库的。

在secp256k1-master/src/java中包括生成java调用secp256k1库的jni的库文件，需要编译生成。

./autogen.sh
    ./ sudo ./configure  --enable-jni --enable-module_ecdh --enable-experimental
    make
    ./tests
    sudo make install  # optional

最后生成的文件在secp256k1-master/.libs中可以查看  
![SouthEast][]

## Windows Build steps ##

libsecp256k1 Windows下编译；在源文件目录中：E:\\work\\secp256k1-master\\builds\\msvc包含几个路径

![SouthEast 1][]

这里有几个Visual Studio版本的编译环境（我使用的是Visual Studio 2012）；

![SouthEast 2][]

打开文件看到三个工程，

![SouthEast 3][]

首先编译secp256K1，生成secp256k1.dll，secp256k1.lib保存在\\secp256k1-master\\bin\\Win32\\Debug\\v110\\dynamic路径中。

![SouthEast 4][]

新建dll工程，编译jni文件；将\\work\\secp256k1-master\\src\\java中的文件添加到工程中；配置好路径

![SouthEast 5][]

将secp256k1.dll，secp256k1.lib添加到工程中；

![SouthEast 6][]

最后生成动态库。

![SouthEast 7][]

##     ##

[https_github.com_bitcoin-core_secp256k1]: https://github.com/bitcoin-core/secp256k1
[SouthEast]: /images/20220601/13d8e0c4fa734b6f84ea277b388788a1.png
[SouthEast 1]: /images/20220601/96e126455c0d474abf981d9ac58d84bf.png
[SouthEast 2]: /images/20220601/8de13e4d95df428896dc6406b8302754.png
[SouthEast 3]: /images/20220601/45f3146e97b44debb0f6dc60d4974d58.png
[SouthEast 4]: /images/20220601/1b4ce46853d4484a9a105cc2177c07c5.png
[SouthEast 5]: /images/20220601/e7cb029e157f4187ab0eb7055c15c46c.png
[SouthEast 6]: /images/20220601/ebea2cbe180b4b27a67909db61777e24.png
[SouthEast 7]: /images/20220601/54b164274d7c4ab2b2bd283258d13c90.png