openssl3.2 - 官方demo学习 - client-arg.c

笔记

client-arg.c

/*! \file client-argc. *//*!
*   \noteadd _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 <string.h>
#include <stdbool.h> // for false
#include <assert.h> // for assert()#include <openssl/err.h>
#include <openssl/ssl.h>#pragma comment(lib, "libcrypto.lib")
#pragma comment(lib, "libssl.lib")#include <openssl/applink.c> /*! 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;
}

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