目的:使用C mbedtls库实现https(RSA证书)双向认证连接。
开发环境:windows 11, VS2022,mbedtls-3.6.2
私钥格式:p1/p8
#include "mbedtls/net_sockets.h"
#include "mbedtls/ssl.h"
#include "mbedtls/entropy.h"
#include "mbedtls/ctr_drbg.h"
#include "mbedtls/debug.h"
#include "mbedtls/error.h"
#include "mbedtls/certs.h"
#include <mbedtls/pk.h>
#include <mbedtls/pem.h>
#include <mbedtls/base64.h>
// 这个函数假设 SSL 握手已经成功完成
void print_server_san(mbedtls_ssl_context* ssl) {
const mbedtls_x509_crt* cert = mbedtls_ssl_get_peer_cert(ssl);
if (cert == NULL) {
printf("No server certificate found.\n");
return;
}
// 确保 `subject_alt_names` 是正确的类型
const mbedtls_x509_sequence* san = &cert->subject_alt_names;
while (san != NULL) {
const mbedtls_asn1_buf* entry = &san->buf;
unsigned char tag = entry->tag;
// 检查是否为 IP 地址 (context-specific tag 7)
if ((tag & MBEDTLS_ASN1_TAG_CLASS_MASK) == MBEDTLS_ASN1_CONTEXT_SPECIFIC &&
(tag & MBEDTLS_ASN1_TAG_VALUE_MASK) == 7) {
// IP 地址以二进制形式存储
if (entry->len == 4) { // IPv4 地址
printf("Server certificate SAN (IP): %u.%u.%u.%u\n",
entry->p[0], entry->p[1], entry->p[2], entry->p[3]);
}
else if (entry->len == 16) { // IPv6 地址
printf("Server certificate SAN (IPv6): ");
for (int i = 0; i < 16; i++) {
printf("%02x", entry->p[i]);
if (i % 2 == 1 && i < 15) {
printf(":");
}
}
printf("\n");
}
}
san = san->next;
}
}
void print_mbedtls_error(int ret) {
char error_buf[100];
mbedtls_strerror(ret, error_buf, sizeof(error_buf));
fprintf(stderr, "Error: %s\n", error_buf);
}
int print_prikey_b64() {
int ret;
mbedtls_pk_context pkey;
unsigned char* key_buffer = NULL;
size_t key_len = 0;
unsigned char* base64_buffer = NULL;
size_t base64_len = 0;
mbedtls_pk_init(&pkey);
// 读取私钥文件
ret = mbedtls_pk_parse_keyfile(&pkey, "res/yax/client_p8.key", NULL);
if (ret != 0) {
print_mbedtls_error(ret);
goto cleanup;
}
// 获取私钥的 DER 格式所需的缓冲区长度
key_len = mbedtls_pk_write_key_der(&pkey, NULL, 0);
if (key_len <= 0) {
print_mbedtls_error(key_len);
goto cleanup;
}
printf("Key length required for DER format: %zu bytes\n", key_len);
// 分配比所需长度更大的缓冲区来确保足够的空间
key_buffer = (unsigned char*)malloc(key_len);
if (!key_buffer) {
fprintf(stderr, "Memory allocation failed for key_buffer with size %zu bytes\n", key_len);
ret = -1;
goto cleanup;
}
// 将私钥写入 DER 格式缓冲区,注意返回值是实际写入的字节数
ret = mbedtls_pk_write_key_der(&pkey, key_buffer, key_len);
if (ret < 0) {
print_mbedtls_error(ret);
goto cleanup;
}
// 计算 Base64 编码所需的缓冲区长度
key_len = ret; // 实际写入的字节数
ret = mbedtls_base64_encode(NULL, 0, &base64_len, key_buffer + (key_len - ret), key_len);
if (ret != MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL) {
print_mbedtls_error(ret);
goto cleanup;
}
// 分配缓冲区以存储 Base64 编码的数据
base64_buffer = (unsigned char*)malloc(base64_len);
if (!base64_buffer) {
fprintf(stderr, "Memory allocation failed for base64_buffer\n");
ret = -1;
goto cleanup;
}
// 将 DER 格式的私钥转换为 Base64 编码
ret = mbedtls_base64_encode(base64_buffer, base64_len, &base64_len, key_buffer + (key_len - ret), key_len);
if (ret != 0) {
print_mbedtls_error(ret);
goto cleanup;
}
// 打印 Base64 编码的私钥
printf("Base64 Encoded Private Key:\n%s\n", base64_buffer);
cleanup:
mbedtls_pk_free(&pkey);
if (key_buffer) {
free(key_buffer);
}
if (base64_buffer) {
free(base64_buffer);
}
//Key length required for DER format: 18446744073709551508 bytes
//Memory allocation failed for key_buffer with size 18446744073709551508 bytes
return ret != 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}
int testHttps_p8() {
printf("Https功能演示start:\n");
int ret;
mbedtls_net_context server_fd;
mbedtls_ssl_context ssl;
mbedtls_ssl_config conf;
mbedtls_x509_crt cacert, clicert;
mbedtls_pk_context pkey;
mbedtls_entropy_context entropy;
mbedtls_ctr_drbg_context ctr_drbg;
const char* pers = "ssl_client1";
// Initialize structures
mbedtls_net_init(&server_fd);
mbedtls_ssl_init(&ssl);
mbedtls_ssl_config_init(&conf);
mbedtls_x509_crt_init(&cacert);
mbedtls_x509_crt_init(&clicert);
mbedtls_pk_init(&pkey);
mbedtls_ctr_drbg_init(&ctr_drbg);
mbedtls_entropy_init(&entropy);
// 设置 RNG
//ret = mbedtls_ctr_drbg_seed(&(hc->tls.ctr_drbg), mbedtls_entropy_func, &hc->tls.entropy, NULL, 0);
//ret = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy, (const unsigned char*)pers, strlen(pers));
ret = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy, NULL, 0);
if (ret != 0)
{
return ret;
}
// Load certificates
//mbedtls_x509_crt_parse_file(&clicert, "res/yax/client_https_with_chain.cer"); //含有客户端证书链
mbedtls_x509_crt_parse_file(&clicert, "res/yax/client_https.cer"); //不含有证书链
mbedtls_x509_crt_parse_file(&cacert, "res/yax/ca.cer"); //所有客户端和服务端所有证书链
//mbedtls_x509_crt_parse_file(&cacert, "res/yax/root.cer"); //只提供一个服务器证书的root证书即可
mbedtls_pk_parse_keyfile(&pkey, "res/yax/client_p8.key", NULL); //p1或p8格式都可以,但必须包含头尾
//mbedtls_pk_parse_keyfile(&pkey, "res/yax2/client_p8.key", NULL);
mbedtls_ssl_conf_authmode(&ssl, MBEDTLS_SSL_VERIFY_REQUIRED); //设置认证模式为 MBEDTLS_SSL_VERIFY_OPTIONAL 或 MBEDTLS_SSL_VERIFY_NONE 来调试是否由于证书验证失败引起的问题
//但是,这仅用于调试,生产环境应该始终使用 MBEDTLS_SSL_VERIFY_REQUIRED。
// Seed the random number generator
//mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy, (const unsigned char*)pers, strlen(pers));
// Setup SSL configuration
mbedtls_ssl_config_defaults(&conf, MBEDTLS_SSL_IS_CLIENT, MBEDTLS_SSL_TRANSPORT_STREAM, MBEDTLS_SSL_PRESET_DEFAULT);
mbedtls_ssl_conf_rng(&conf, mbedtls_ctr_drbg_random, &ctr_drbg);
mbedtls_ssl_conf_dbg(&conf, my_debug, stdout);
mbedtls_ssl_conf_ca_chain(&conf, &cacert, NULL);
mbedtls_ssl_conf_own_cert(&conf, &clicert, &pkey);
//mbedtls_ssl_set_hostname(&ssl, "4.3.2.1"); //服务器证书alt name dns = ip而不是域名时,不要调用这个
//mbedtls_ssl_set_hostname(&ssl, NULL); //忽略主机名验证
//mbedtls_ssl_conf_verify(&conf, 0, NULL); // 设置自定义的证书验证回调
// Connect to server
mbedtls_net_connect(&server_fd, "4.3.2.1", "443", MBEDTLS_NET_PROTO_TCP); //rsa https 测试服务端
//mbedtls_net_connect(&server_fd, "4.3.2.1", "443", MBEDTLS_NET_PROTO_TCP); //RSA 国密sm2 双算法证书https 不适用。
// Setup SSL context
mbedtls_ssl_setup(&ssl, &conf);
mbedtls_ssl_set_bio(&ssl, &server_fd, mbedtls_net_send, mbedtls_net_recv, NULL);
// Perform SSL handshake
while ((ret = mbedtls_ssl_handshake(&ssl)) != 0) {
if (ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE) {
char error_buf[100];
mbedtls_strerror(ret, error_buf, 100);
printf("Handshake failed: %s\n", error_buf);
return 1;
}
}
//打印服务器证书的san
print_server_san(&ssl);
//print_prikey_b64();
// Communicate with the server
// ...
// Send data to server
const char* msg = "Hello, Server!";
mbedtls_ssl_write(&ssl, (const unsigned char*)msg, strlen(msg));
// Read response
char buffer[1024];
do {
memset(buffer, 0, sizeof(buffer));
ret = mbedtls_ssl_read(&ssl, (unsigned char*)buffer, sizeof(buffer) - 1);
if (ret > 0) {
printf("Received %d bytes:\n%s\n", ret, buffer);
}
else if (ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE) {
break;
}
} while (ret > 0);
// Clean up
mbedtls_ssl_close_notify(&ssl);
mbedtls_net_free(&server_fd);
mbedtls_x509_crt_free(&cacert);
mbedtls_x509_crt_free(&clicert);
mbedtls_pk_free(&pkey);
mbedtls_ssl_free(&ssl);
mbedtls_ssl_config_free(&conf);
mbedtls_ctr_drbg_free(&ctr_drbg);
mbedtls_entropy_free(&entropy);
printf("Https功能演示End:\n");
return EXIT_SUCCESS;
}
//在证书base64编码前后添加头尾
char* cert_add_ht(const char* filename) {
FILE* file = fopen(filename, "r");
if (!file) {
perror("无法打开文件");
return NULL;
}
// 获取文件大小
fseek(file, 0, SEEK_END);
long filesize = ftell(file);
fseek(file, 0, SEEK_SET);
// 分配内存读取文件内容
char* base64_data = (char*)malloc(filesize + 1);
if (!base64_data) {
perror("内存分配失败");
fclose(file);
return NULL;
}
fread(base64_data, 1, filesize, file);
base64_data[filesize] = '\0'; // 确保字符串结束
fclose(file);
const char* pem_header = "-----BEGIN CERTIFICATE-----\n";
const char* pem_footer = "\n-----END CERTIFICATE-----\n";
// 计算 PEM 格式总长度
size_t pem_size = strlen(pem_header) + strlen(base64_data) + strlen(pem_footer) + 1;
// 分配内存以存储 PEM 格式数据
char* pem_cert = (char*)malloc(pem_size);
if (!pem_cert) {
perror("内存分配失败");
free(base64_data);
return NULL;
}
// 生成 PEM 格式数据
snprintf(pem_cert, pem_size, "%s%s%s", pem_header, base64_data, pem_footer);
free(base64_data);
return pem_cert;
}
char* pkcs1_key_add_ht(const char* filename) {
FILE* file = fopen(filename, "r");
if (!file) {
perror("无法打开文件");
return NULL;
}
// 获取文件大小
fseek(file, 0, SEEK_END);
long filesize = ftell(file);
fseek(file, 0, SEEK_SET);
// 分配内存读取文件内容
char* base64_data = (char*)malloc(filesize + 1);
if (!base64_data) {
perror("内存分配失败");
fclose(file);
return NULL;
}
fread(base64_data, 1, filesize, file);
base64_data[filesize] = '\0'; // 确保字符串结束
fclose(file);
const char* pem_header = "-----BEGIN RSA PRIVATE KEY-----\n";
const char* pem_footer = "\n-----END RSA PRIVATE KEY-----\n";
// 计算 PEM 格式总长度
size_t pem_size = strlen(pem_header) + strlen(base64_data) + strlen(pem_footer) + 1;
// 分配内存以存储 PEM 格式数据
char* pem_cert = (char*)malloc(pem_size);
if (!pem_cert) {
perror("内存分配失败");
free(base64_data);
return NULL;
}
// 生成 PEM 格式数据
snprintf(pem_cert, pem_size, "%s%s%s", pem_header, base64_data, pem_footer);
free(base64_data);
return pem_cert;
}
int testHttps() {
printf("Https功能演示start:\n");
int ret;
mbedtls_net_context server_fd;
mbedtls_ssl_context ssl;
mbedtls_ssl_config conf;
mbedtls_x509_crt cacert, clicert;
mbedtls_pk_context pkey;
mbedtls_entropy_context entropy;
mbedtls_ctr_drbg_context ctr_drbg;
const char* pers = "ssl_client1";
// Initialize structures
mbedtls_net_init(&server_fd);
mbedtls_ssl_init(&ssl);
mbedtls_ssl_config_init(&conf);
mbedtls_x509_crt_init(&cacert);
mbedtls_x509_crt_init(&clicert);
mbedtls_pk_init(&pkey);
mbedtls_ctr_drbg_init(&ctr_drbg);
mbedtls_entropy_init(&entropy);
// 设置 RNG
//ret = mbedtls_ctr_drbg_seed(&(hc->tls.ctr_drbg), mbedtls_entropy_func, &hc->tls.entropy, NULL, 0);
//ret = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy, (const unsigned char*)pers, strlen(pers));
ret = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy, NULL, 0);
if (ret != 0)
{
return ret;
}
const char* file_cert_b64 = "res/yax2/client_https_noht.cer";
// 读取证书文件(不包含头尾)并转换为 PEM 格式(包含头尾)
char* pem_cert = cert_add_ht(file_cert_b64);
// 获取 PEM 证书的大小
size_t pem_size = strlen(pem_cert) + 1; // 包括终止符
mbedtls_x509_crt_parse(&clicert, (const unsigned char*)pem_cert, pem_size);
free(pem_cert);
const char* file_key_p1_b64 = "res/yax2/client_p1_noht.key";
// 读取证书文件(不包含头尾)并转换为 PEM 格式(包含头尾)
char* pem_key = pkcs1_key_add_ht(file_key_p1_b64);
// 获取 PEM 证书的大小
size_t key_size = strlen(pem_key) + 1; // 包括终止符
mbedtls_pk_parse_key(&pkey, (const unsigned char*)pem_key, key_size,NULL,0);
free(pem_key);
mbedtls_x509_crt_parse_file(&cacert, "res/yax/ca.cer"); //所有客户端和服务端所有证书链
// Load certificates
//mbedtls_x509_crt_parse_file(&clicert, "res/yax/client_https_with_chain.cer"); //含有客户端证书链
//mbedtls_x509_crt_parse_file(&clicert, "res/yax2/client_https_noht.cer"); //不含有证书链
//mbedtls_x509_crt_parse_file(&cacert, "res/yax/ca.cer"); //所有客户端和服务端所有证书链
//mbedtls_x509_crt_parse_file(&cacert, "res/yax/root.cer"); //只提供一个服务器证书的root证书即可
//mbedtls_pk_parse_keyfile(&pkey, "res/yax2/client_p1.key", NULL); //p1或p8格式都可以,但必须包含头尾
//mbedtls_pk_parse_keyfile(&pkey, "res/yax2/client_p8.key", NULL);
mbedtls_ssl_conf_authmode(&ssl, MBEDTLS_SSL_VERIFY_REQUIRED); //设置认证模式为 MBEDTLS_SSL_VERIFY_OPTIONAL 或 MBEDTLS_SSL_VERIFY_NONE 来调试是否由于证书验证失败引起的问题
//但是,这仅用于调试,生产环境应该始终使用 MBEDTLS_SSL_VERIFY_REQUIRED。
// Seed the random number generator
//mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy, (const unsigned char*)pers, strlen(pers));
// Setup SSL configuration
mbedtls_ssl_config_defaults(&conf, MBEDTLS_SSL_IS_CLIENT, MBEDTLS_SSL_TRANSPORT_STREAM, MBEDTLS_SSL_PRESET_DEFAULT);
mbedtls_ssl_conf_rng(&conf, mbedtls_ctr_drbg_random, &ctr_drbg);
mbedtls_ssl_conf_dbg(&conf, my_debug, stdout);
mbedtls_ssl_conf_ca_chain(&conf, &cacert, NULL);
mbedtls_ssl_conf_own_cert(&conf, &clicert, &pkey);
//mbedtls_ssl_set_hostname(&ssl, "1.2.3.4"); //服务器证书alt name dns = ip而不是域名时,不要调用这个
//mbedtls_ssl_set_hostname(&ssl, NULL); //忽略主机名验证
//mbedtls_ssl_conf_verify(&conf, 0, NULL); // 设置自定义的证书验证回调
// Connect to server
mbedtls_net_connect(&server_fd, "2.3.4.5", "443", MBEDTLS_NET_PROTO_TCP); //rsa https 测试服务端
//mbedtls_net_connect(&server_fd, "2.3.4.5", "443", MBEDTLS_NET_PROTO_TCP); //RSA 国密sm2 双算法证书https 不适用。
// Setup SSL context
mbedtls_ssl_setup(&ssl, &conf);
mbedtls_ssl_set_bio(&ssl, &server_fd, mbedtls_net_send, mbedtls_net_recv, NULL);
// Perform SSL handshake
while ((ret = mbedtls_ssl_handshake(&ssl)) != 0) {
if (ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE) {
char error_buf[100];
mbedtls_strerror(ret, error_buf, 100);
printf("Handshake failed: %s\n", error_buf);
return 1;
}
}
//打印服务器证书的san
print_server_san(&ssl);
//print_prikey_b64();
// Communicate with the server
// ...
// Send data to server
const char* msg = "Hello, Server!";
mbedtls_ssl_write(&ssl, (const unsigned char*)msg, strlen(msg));
// Read response
char buffer[1024];
do {
memset(buffer, 0, sizeof(buffer));
ret = mbedtls_ssl_read(&ssl, (unsigned char*)buffer, sizeof(buffer) - 1);
if (ret > 0) {
printf("Received %d bytes:\n%s\n", ret, buffer);
}
else if (ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE) {
break;
}
} while (ret > 0);
// Clean up
mbedtls_ssl_close_notify(&ssl);
mbedtls_net_free(&server_fd);
mbedtls_x509_crt_free(&cacert);
mbedtls_x509_crt_free(&clicert);
mbedtls_pk_free(&pkey);
mbedtls_ssl_free(&ssl);
mbedtls_ssl_config_free(&conf);
mbedtls_ctr_drbg_free(&ctr_drbg);
mbedtls_entropy_free(&entropy);
printf("Https功能演示End:\n");
return EXIT_SUCCESS;
}