X509格式的证书校验（基于GMSSL2019-06-15版本）

实现X509格式证书的链式校验

// cert_public.cpp : Defines the exported functions for the DLL application.
//

#include "stdafx.h"
#include <string.h>
#include <stdio.h>
#include <string>

#include <stdarg.h>

#include <openssl/pem.h>
#include <openssl/x509.h>
#include <openssl/x509v3.h>

#include "sm_public.h"

extern "C" {

/*****************************************************************************
* @brief    : 通过X509格式的字符串得到一个X509内部结构对象
* @author   : xiaomw
* @date     : 2019/8/13 
* @inparam  : plaintext X509格式的字符串
* @return   : 成功返回非0 失败返回0
*****************************************************************************/
CRYPT_SMDLL_C void* X509_Str2Object(const char *in)
{
    BIO *bio_obj = NULL;
    X509* x509_obj = NULL;

    //根据字符串内容，构造一个BIO对象
    bio_obj = BIO_new_mem_buf(in, strlen(in));
    if (NULL == bio_obj){
        return NULL;
    }

    //调用接口创建呗
    x509_obj = (X509 *) PEM_ASN1_read_bio((d2i_of_void *)d2i_X509, PEM_STRING_X509, bio_obj, NULL, NULL, NULL);

    //释放对象
    BIO_free(bio_obj);

    return x509_obj;
}

X509* _X509_RootCertStr2Object(const char *in)
{
    BIO *bio_obj = NULL;
    X509* x509_obj = NULL;
    X509_INFO *itmp  = NULL;
    STACK_OF(X509_INFO) *inf  = NULL;

    //根据字符串内容，构造一个BIO对象
    bio_obj = BIO_new_mem_buf(in, strlen(in));
    if (NULL == bio_obj){
        return NULL;
    }
    inf = PEM_X509_INFO_read_bio(bio_obj, NULL, NULL, NULL);
    //释放对象
    BIO_free(bio_obj);
    if (NULL == inf){
        return NULL;
    }

    for (int i = 0; i < sk_X509_INFO_num(inf); i++) {
        itmp = sk_X509_INFO_value(inf, i);
        if (itmp->x509) {
            //复制一个X509对象
            x509_obj = X509_dup(itmp->x509);
            sk_X509_INFO_pop_free(inf, X509_INFO_free);
            return x509_obj;
        }
    }
    sk_X509_INFO_pop_free(inf, X509_INFO_free);

    return NULL;
}

static UINT32 _x509_get_entry_value(const X509_NAME* x509_name, X509_NAME_ENTRY_TYPE nEntry, char* value)
{
    ASN1_STRING* strNameValue = NULL;
    const X509_NAME_ENTRY *x_name_entry = NULL;

    //获取到相应的NameEntry
    x_name_entry = X509_NAME_get_entry(x509_name, nEntry);
    if (NULL == x_name_entry)
    {
        return 1;
    }

    strNameValue = X509_NAME_ENTRY_get_data(x_name_entry);
    if (NULL == strNameValue)
    {
        return 1;
    }

    //拷贝内容
    lstrcpyA(value, (const char*)ASN1_STRING_data(strNameValue));

    return 0;
}

CRYPT_SMDLL_C UINT32 X509_GetIssuerName(const void* pX509_object, X509_NAME_ENTRY_TYPE nEntry, char* value)
{
    const X509_NAME* x_name = NULL;
    ASN1_STRING* strNameValue = NULL;
    const X509_NAME_ENTRY *x_name_entry = NULL;

    if (NULL == pX509_object)
    {
        return 1;
    }

    //校验nEntry
    if (nEntry < NID_commonName || nEntry > NID_organizationalUnitName)
    {
        return 1;
    }

    //获取到值
    x_name = X509_get_issuer_name((const X509*)pX509_object);
    if (NULL == x_name)
    {
        return 1;
    }

    //调用一样的接口返回
    return _x509_get_entry_value(x_name, nEntry, value);
}

CRYPT_SMDLL_C UINT32 X509_GetSubjectName(const void* pX509_object, X509_NAME_ENTRY_TYPE nEntry, char* value)
{
    const X509_NAME* x_name = NULL;
    ASN1_STRING* strNameValue = NULL;
    const X509_NAME_ENTRY *x_name_entry = NULL;

    if (NULL == pX509_object)
    {
        return 1;
    }

    //校验nEntry
    if (nEntry < NID_commonName || nEntry > NID_organizationalUnitName)
    {
        return 1;
    }

    //获取到值
    x_name = X509_get_subject_name((const X509*)pX509_object);
    if (NULL == x_name)
    {
        return 1;
    }

    //调用一样的接口返回
    return _x509_get_entry_value(x_name, nEntry, value);
}

class Mini_X509_Verify_Class
{
private:
    X509* x509_obj;
    X509_STORE * x509_store;
    STACK_OF(X509) * x509_chain;
    X509_STORE_CTX * x509_store_ctx;

public:
    Mini_X509_Verify_Class(): x509_obj(NULL), x509_store(NULL), x509_chain(NULL), x509_store_ctx(NULL){}
    ~Mini_X509_Verify_Class()
    {
        if (NULL != x509_obj){
            X509_free(x509_obj);
        }
        if (NULL != x509_store){
            X509_STORE_free(x509_store);
        }
        if (NULL != x509_chain){
            sk_X509_pop_free(x509_chain, X509_free);
        }
        if (NULL != x509_store_ctx){
            X509_STORE_CTX_cleanup(x509_store_ctx);
        }
    }

    UINT32 set_verify_cert(const char* cert)
    {
        x509_obj = (X509*)X509_Str2Object(cert);
        if (NULL == x509_obj){
            return 1;
        }
        return 0;
    }

    UINT32 add_root_cert(const char* root_cert)
    {
        //没有存储对象，则先创建一个
        if (NULL == x509_store){
            x509_store = X509_STORE_new();
            if (NULL == x509_store)
            {
                return 1;
            }
        }

        //得到X509对象
        X509* x509_root_obj = (X509*)_X509_RootCertStr2Object(root_cert);
        if (NULL == x509_root_obj){
            return 1;
        }
        //加入存储区
        if (0 == X509_STORE_add_cert(x509_store, x509_root_obj)){

            X509_free(x509_root_obj);
            return 1;
        }

        return 0;
    }

    UINT32 add_cert_chain(const char* cert_node)
    {
        //没有X509链，则先创建一个
        if (NULL == x509_chain){
            x509_chain = sk_X509_new_null();
            if (NULL == x509_chain)
            {
                return 1;
            }
        }

        //得到X509对象
        X509* x509_node_obj = (X509*)X509_Str2Object(cert_node);
        if (NULL == x509_node_obj){
            return 1;
        }
        //加入X509链
        if (0 == sk_X509_push(x509_chain, x509_node_obj)){

            X509_free(x509_node_obj);
            return 1;
        }

        return 0;
    }

    BOOL verify(X509* cert)
    {
        X509* pTemp = NULL;
        EVP_PKEY *pkey=NULL;
        // 每次都采取遍历证书的办法吧
        if (NULL != x509_chain){
            //获取链条总长度
            int nSize = sk_X509_num(x509_chain);
            for (int index = 0; index < nSize; index ++) {
                //取出相应的数值
                pTemp = sk_X509_value(x509_chain, index);
                //取出公钥
                pkey = X509_get_pubkey(pTemp);
                //测试能否验证过，能够验证过，递归下去验证
                if (X509_verify(cert, pkey)){
                    return verify(pTemp);
                }
            }
        }

        //如果链条中都验证不过，试一下根证书
        STACK_OF(X509_OBJECT) * root_obj = X509_STORE_get0_objects(x509_store);
        if (NULL == root_obj) {
            return FALSE;
        }
        int root_obj_num = sk_X509_OBJECT_num(root_obj);
        if (root_obj_num <= 0) {
            return FALSE;
        }

        X509 *root_cert = NULL;
        X509_OBJECT* x509_obj = NULL;
        for(int j = 0; j < root_obj_num; j ++){
            //取出OBJ
            x509_obj = sk_X509_OBJECT_value(root_obj, j);
            //取出证书
            root_cert = X509_OBJECT_get0_X509(x509_obj);
            //取出公钥
            pkey = X509_get_pubkey(root_cert);
            //测试能否验证过，能够验证过，返回成功
            if (X509_verify(cert, pkey)){
                return TRUE;
            }
        }

        return FALSE;
    }

    UINT32 verify_cert()
    {
        if (!x509_obj){
            return 1;
        }
        if (verify(x509_obj)) {
            return 0;
        }

        return 1;
    }
};


// 验证一个证书，输入根证书及相应的二级、三级...证书
UINT32 X509_Verify(const char *cert, const char* root_cert, UINT32 ulLevelNum, ...)
{
    UINT32 index = 0;
    va_list arg_ptr;
    const char* cert_node = NULL;
    Mini_X509_Verify_Class x509_verify;

    if (NULL == cert)
    {
        return 1;
    }
    if (NULL == root_cert)
    {
        return 1;
    }
    //最多支持6级
    if (ulLevelNum > 6)
    {
        return 1;
    }

    //存放待验证证书
    if (x509_verify.set_verify_cert(cert)) {
        return 1;
    }

    //存放根证书
    if (x509_verify.add_root_cert(root_cert)) {
        return 1;
    }

    va_start(arg_ptr, ulLevelNum);
    for(index = 0; index < ulLevelNum; index ++){
        cert_node = va_arg(arg_ptr, const char*);
        //存放证书链接
        if (x509_verify.add_cert_chain(cert_node)) {
            return 1;
        }
    }
    va_end(arg_ptr);

    //开始校验
    if (x509_verify.verify_cert()) {
        return 1;
    }

    return 0;
}

};

DEMO验证代码

BOOL LoadCertFileToStr(const char* strFile, std::string& strBuff)
{
    // 打开文件，读取内容
    FILE * hSrcfile = NULL;
    fopen_s(&hSrcfile, strFile,"rb");
    if (hSrcfile == NULL) {
        return FALSE;
    }
    //读取文件
    fseek (hSrcfile, 0, SEEK_END);   ///将文件指针移动文件结尾
    long size = ftell (hSrcfile); ///求出当前文件指针距离文件开始的字节数

    //分配内存
    strBuff.resize(size + 1, '\0');
    //重新开始读取文件
    fseek (hSrcfile, 0, SEEK_SET);

    //读取文件
    fread(&strBuff[0], size,1, hSrcfile);

    fclose(hSrcfile);

    return TRUE;
}

int main(int argc, char* argv[])
{
    //cwSL3D_test_sum();//测试能否成功调用所有接口

    //至少两个证书文件
    if (argc < 3) {
        std::cout << "缺少证书文件" << std::endl;
        return -1;
    }
    if (argc > 9) {
        std::cout << "证书文件过多，目前不支持" << std::endl;
        return -1;
    }

    //第一个证书文件，根证书文件
    std::string root_cert;
    if (!LoadCertFileToStr(argv[1], root_cert)) {
        std::cout << "读取根证书文件失败" << std::endl;
        return -1;
    }

    //第二个证书文件，待验证的证书
    std::string cert_file;
    if (!LoadCertFileToStr(argv[2], cert_file)) {
        std::cout << "读取待验证证书文件失败" << std::endl;
        return -1;
    }

    //后续的证书文件，证书链条上的文件
    std::string cert_chain[6];
    for(int index = 0; index < 6 && index < argc - 3; index ++) {
        if (!LoadCertFileToStr(argv[index + 3], cert_chain[index])) {
            std::cout << "读取证书文件失败:" << argv[index + 2] << std::endl;
            return -1;
        }
    }

    //直接调用接口验证吧
    if (X509_Verify(cert_file.c_str(), root_cert.c_str(), argc - 3, cert_chain[0].c_str(), cert_chain[1].c_str(), cert_chain[2].c_str(), cert_chain[3].c_str(), cert_chain[4].c_str(), cert_chain[5].c_str())) {
        std::cout << "验证证书文件失败" << std::endl;
        return -1;
    }

    return 0;
}