openssl3.2 - 官方dmeo学习 - client-arg.c

openssl3.2 - 官方dmeo学习 - client-arg.c

笔记

client-arg.c

/*! \file client-argc. */

/*!
*   \note
	add _CRT_SECURE_NO_WARNINGS to VS2019 option
*/

/*
 * Copyright 2013-2023 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the Apache License 2.0 (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

#include 
#include  // for false
#include  // for assert()

#include 
#include 

#pragma comment(lib, "libcrypto.lib")
#pragma comment(lib, "libssl.lib")

#include  /*! for OPENSSL_Uplink(00007FF8B7EF0FE8,08): no OPENSSL_Applink */

 /*! client-arg.c 是个TLS客户端程序 */
int main(int argc, char** argv)
{
	FILE* fpFileOut = NULL;
	FILE* fpFileErr = NULL;

	BIO* sbio = NULL, * out = NULL;
	int len;
	char tmpbuf[1024];
	SSL_CTX* ctx;
	SSL_CONF_CTX* cctx;
	SSL* ssl;
	char** args = argv + 1;
	const char* connect_str = "localhost:4433";
	int nargs = argc - 1;
	int ret = EXIT_FAILURE;

	do {
		fpFileOut = fopen("prj_out.txt", "wb");
		assert(NULL != fpFileOut);

		fpFileErr = fopen("prj_log.log", "wb");
		assert(NULL != fpFileErr);

		ctx = SSL_CTX_new(TLS_client_method());
		cctx = SSL_CONF_CTX_new();
		SSL_CONF_CTX_set_flags(cctx, SSL_CONF_FLAG_CLIENT);
		SSL_CONF_CTX_set_ssl_ctx(cctx, ctx);

		// 可以由外面给定TLS服务器ip/port, 这里用connect_str
		//while (*args && **args == '-') {
		//    int rv;
		//    /* Parse standard arguments */
		//    rv = SSL_CONF_cmd_argv(cctx, &nargs, &args);
		//    if (rv == -3) {
		//        fprintf(stderr, "Missing argument for %s\n", *args);
		//        goto end;
		//    }
		//    if (rv < 0) {
		//        fprintf(stderr, "Error in command %s\n", *args);
		//        ERR_print_errors_fp(stderr);
		//        goto end;
		//    }
		//    /* If rv > 0 we processed something so proceed to next arg */
		//    if (rv > 0)
		//        continue;
		//    /* Otherwise application specific argument processing */
		//    if (strcmp(*args, "-connect") == 0) {
		//        connect_str = args[1];
		//        if (connect_str == NULL) {
		//            fprintf(stderr, "Missing -connect argument\n");
		//            goto end;
		//        }
		//        args += 2;
		//        nargs -= 2;
		//        continue;
		//    } else {
		//        fprintf(stderr, "Unknown argument %s\n", *args);
		//        goto end;
		//    }
		//}

		if (!SSL_CONF_CTX_finish(cctx)) {
			fprintf(fpFileErr, "Finish error\n");
			ERR_print_errors_fp(fpFileErr);
			break;
		}

		/*
		 * We'd normally set some stuff like the verify paths and * mode here
		 * because as things stand this will connect to * any server whose
		 * certificate is signed by any CA.
		 */

		/*! 从ssl上下文中来的bio */
		sbio = BIO_new_ssl_connect(ctx);

		BIO_get_ssl(sbio, &ssl);

		if (!ssl) {
			fprintf(fpFileErr, "Can't locate SSL pointer\n");
			break;
		}

		/* We might want to do other things with ssl here */

		BIO_set_conn_hostname(sbio, connect_str);

		/*! 从文件中来的bio 
		* 为了适应非命令行程序, 将stdout, stderr换成自己的实际文件FILE*
		*/

		out = BIO_new_fp(fpFileOut, BIO_NOCLOSE); /*!< OPENSSL_Uplink(00007FF8B7EF0FE8,08): no OPENSSL_Applink */
		if (BIO_do_connect(sbio) <= 0) {
			fprintf(fpFileErr, "Error connecting to server\n");
			ERR_print_errors_fp(fpFileErr);
			break;
		}

		/* Could examine ssl here to get connection info */

		BIO_puts(sbio, "GET / HTTP/1.0\n\n");
		for (;;) {
			len = BIO_read(sbio, tmpbuf, 1024);
			if (len <= 0)
				break;
			BIO_write(out, tmpbuf, len);
		}
		ret = EXIT_SUCCESS;

	} while (false);

	SSL_CONF_CTX_free(cctx); /*! 已经将ctx配置进了cctx, 所以不用释放ctx, 由cctx负责释放ctx */

	/*! 由BIO_new_xx()来的BIO*, 必须调用BIO_free来释放 */
	BIO_free_all(sbio); /*! 由ssl链接上下文来的bio*, 要调用BIO_free_all() */
	BIO_free(out); /*! 由文件来的bio*, 调用BIO_free() */

	if (NULL != fpFileOut)
	{
		fclose(fpFileOut);
		fpFileOut = NULL;
	}

	if (NULL != fpFileErr)
	{
		fclose(fpFileErr);
		fpFileErr = NULL;
	}

	printf("END\n");

	return ret;
}

备注

openssl3.2 - 官方dmeo学习 - 索引贴

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