X509格式的证书转换成pem格式的C语言代码示例
时间: 2023-07-09 16:08:13 浏览: 94
以下是将X509格式的证书转换成PEM格式的C语言代码示例:
```c
#include <stdio.h>
#include <openssl/x509.h>
#include <openssl/pem.h>
int main()
{
X509 *cert = NULL;
FILE *x509_file = fopen("x509_cert.crt", "r");
if (!x509_file) {
printf("Failed to open x509 certificate file.\n");
return -1;
}
// 读取X509格式的证书
cert = PEM_read_X509(x509_file, NULL, NULL, NULL);
fclose(x509_file);
if (!cert) {
printf("Failed to read X509 certificate.\n");
return -1;
}
FILE *pem_file = fopen("pem_cert.pem", "w");
if (!pem_file) {
printf("Failed to create PEM certificate file.\n");
X509_free(cert);
return -1;
}
// 将X509证书转换成PEM格式的证书,并输出到文件中
if (PEM_write_X509(pem_file, cert) != 1) {
printf("Failed to write PEM certificate.\n");
fclose(pem_file);
X509_free(cert);
return -1;
}
fclose(pem_file);
X509_free(cert);
printf("X509 certificate successfully converted to PEM format.\n");
return 0;
}
```
需要注意的是,在编译时需要链接OpenSSL库。例如,使用以下命令进行编译:
```
gcc -o x509_to_pem x509_to_pem.c -lssl -lcrypto
```