开源库BearSSL介绍及使用

向右看齐 2023-07-15 02:58 11阅读 0赞

BearSSL是用C语言实现的SSL/TLS协议，它的源码可直接通过git clone [https://www.bearssl.org/git/BearSSL][https_www.bearssl.org_git_BearSSL] 下载，它的license是MIT，最新版本为0.6。

BearSSL的主要特性是：

(1). 正确且安全：对不安全的协议版本和算法选择是不支持的，密码算法的实现默认采用固定时间(constant-time)。

(2). 较少的代码(Be small, both in RAM and code footprint)。

(3). 支持多平台，既支持windows, linux, macOS，又支持小型嵌入式系统。

(4). 可扩展。

编译源码：

(1). Linux：直接执行make即可在build目录下生成动态库和静态库。

(2). Windows：修改src/inner.h文件，在\#include “config.h”行后添加以下语句，然后将src目录下的.c文件加入vs工程中即可设置生成动态库或静态库：

#ifdef _MSC_VER
    #ifndef inline
    #define inline __inline
    #endif
    #endif

以下为测试代码：

#include "funset.hpp"
    #include <string.h>
    #include <string>
    #include <vector>
    #include "bearssl_hash.h"
    #include "bearssl_block.h"
    
    namespace {
    
    void print(const char* name, const unsigned char* data, unsigned int len)
    {
    	fprintf(stdout, "%s:", name);
    	for (unsigned i = 0; i < len; ++i) {
    		fprintf(stdout, "%02X", data[i]);
    	}
    	fprintf(stdout, "\n");
    }
    
    }
    
    int test_bearssl_1()
    {
    	// compute a hash function
    	const std::string data1 = "https://blog.csdn.net/fengbingchun";
    	unsigned char hash_output_sha256[br_sha256_SIZE] = { 0 };
    	br_sha256_context csha256;
    	br_sha256_init(&csha256);
    	br_sha256_update(&csha256, data1.c_str(), data1.length());
    	br_sha256_out(&csha256, hash_output_sha256);
    	print("sha256", hash_output_sha256, br_sha256_SIZE);
    
    	const std::string data2 = "https://github.com/fengbingchun";
    	unsigned char hash_output_sha1[br_sha1_SIZE] = { 0 };
    	br_sha1_context csha1;
    	br_sha1_init(&csha1);
    	br_sha1_update(&csha1, data2.c_str(), data2.length());
    	br_sha1_out(&csha1, hash_output_sha1);
    	print("sha1", hash_output_sha1, br_sha1_SIZE);
    
    	// aes cbc encryption/decryption
    	static const char* const key = "012346789abcdef";
    	static const char* const iv_src = "ABCDEF9876543210";
    	char* data3_src = "!@#$%^&*()_-+={]";
    
    	br_aes_big_cbcenc_keys cbcenc_ctx;
    	br_aes_big_cbcenc_init(&cbcenc_ctx, key, br_aes_big_BLOCK_SIZE);
    	std::vector<unsigned char> iv(br_aes_big_BLOCK_SIZE, 0);
    	memcpy(iv.data(), iv_src, br_aes_big_BLOCK_SIZE);
    	if (strlen(data3_src) % br_aes_big_BLOCK_SIZE != 0) {
    		fprintf(stdout, "data length (in bytes, MUST be multiple of 16): %d\n", strlen(data3_src));
    		return -1;
    	}
    	std::vector<unsigned char> data3(br_aes_big_BLOCK_SIZE, 0);
    	memcpy(data3.data(), data3_src, br_aes_big_BLOCK_SIZE);
    	print("data3 src", data3.data(), br_aes_big_BLOCK_SIZE);
    	br_aes_big_cbcenc_run(&cbcenc_ctx, iv.data(), data3.data(), br_aes_big_BLOCK_SIZE);
    	print("data3 enc", data3.data(), br_aes_big_BLOCK_SIZE);
    
    	br_aes_big_cbcdec_keys cbcdec_ctx;
    	br_aes_big_cbcdec_init(&cbcdec_ctx, key, br_aes_big_BLOCK_SIZE);
    	std::vector<unsigned char> iv2(br_aes_big_BLOCK_SIZE, 0);
    	memcpy(iv2.data(), iv_src, br_aes_big_BLOCK_SIZE);
    	br_aes_big_cbcdec_run(&cbcdec_ctx, iv2.data(), data3.data(), br_aes_big_BLOCK_SIZE);
    	print("data3 dec", data3.data(), br_aes_big_BLOCK_SIZE);
    	fprintf(stdout, "data3 src:          : %s\n", data3_src);
    	fprintf(stdout, "data3 decrypt result: %s\n", data3.data());
    
    	return 0;
    }

执行结果如下图所示：

![20200315121413266.png][]

**GitHub**：[https://github.com/fengbingchun/OpenSSL\_Test][https_github.com_fengbingchun_OpenSSL_Test]

[https_www.bearssl.org_git_BearSSL]: https://www.bearssl.org/git/BearSSL
[20200315121413266.png]: /images/20230529/ce72fcd049d94861ae96950fa1cc5925.png
[https_github.com_fengbingchun_OpenSSL_Test]: https://github.com/fengbingchun/OpenSSL_Test