Openssl验证证书的有效性

好久没写博客了，直接上代码
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <openssl/x509.h>
#include <openssl/x509_vfy.h>
int LoadCert(unsigned char * szFilePath, unsigned char *pbCert, int size)
{
int len = 0;
if(szFilePath == NULL || pbCert == NULL || size < 128)
{
return -1;
}
FILE *fp = fopen(szFilePath, "rb");
if ( NULL == fp)
{
return -2;
}

len = fread(pbCert, 1, size, fp);
fclose(fp);
return len;
}

int VerifyCert(unsigned char *pbCaCert, int nCaLen, unsigned char *pbCert, int nCertLen, unsigned char *pbCN, int size)
{
int rv = -1;
if(pbCaCert == NULL || nCaLen < 128 || pbCert == NULL || nCertLen < 128)
{
return rv;
}

X509 *ca = NULL;
X509 *cert = NULL;

X509_STORE *caStore = NULL;
X509_STORE_CTX *ctx = NULL;
X509_NAME *subject = NULL;

OpenSSL_add_all_algorithms();

caStore = X509_STORE_new();
ctx = X509_STORE_CTX_new();

ca = d2i_X509(NULL, ( const unsigned char **)&pbCaCert, nCaLen);
if(ca == NULL)
{
return -2;
}

rv = X509_STORE_add_cert(caStore, ca);
if ( rv != 1 )
{
rv = -3;
goto EXIT_VERIFY;
}

cert = d2i_X509(NULL, ( const unsigned char **)&pbCert, nCertLen);
if(cert == NULL)
{
rv = -4;
goto EXIT_VERIFY;
}

rv = X509_STORE_CTX_init(ctx, caStore, cert, NULL);
if ( rv != 1 )
{
rv = -5;
goto EXIT_VERIFY;
}

rv = X509_verify_cert(ctx);
if ( rv != 1 )
{
fprintf(stderr, "X509_verify_cert fail, rv = %d, error id = %d, %s\n",
rv, ctx->error, X509_verify_cert_error_string(ctx->error));
rv = (rv == 0 ? 1 : rv);
goto EXIT_VERIFY;
}
subject = X509_get_subject_name(cert);
if(subject)
{
X509_NAME_get_text_by_NID(subject, NID_commonName, pbCN, size);
}
rv = (rv == 1 ? 0 : rv);

EXIT_VERIFY:
if(cert) X509_free(cert);
if(ca) X509_free(ca);
if(caStore) X509_STORE_free(caStore);
if(ctx)
{
X509_STORE_CTX_cleanup(ctx);
X509_STORE_CTX_free(ctx);
}

return rv;
}

int main(void)
{
int rv = 0;
int i = 0;
int caLen = 0;
int certLen =0;
unsigned char cn[255] = {0};
unsigned char cert[4096] = {0};
unsigned char ca[4096] = {0};

caLen = LoadCert("ca.cer", ca, 4096);
certLen = LoadCert("Jinhill.cer", cert, 4096);
rv = VerifyCert(ca, caLen, cert, certLen, cn, 255);
printf("rv=%d, cn=%s\n", rv, cn);
return 0;

}