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源代码如下：
| #include <stdio.h>#include <stdlib.h>#include <string.h>#include <sys/types.h>#include <sys/socket.h>#include <errno.h>#include <unistd.h>#include <netinet/in.h>#include <limits.h>#include <netdb.h>#include <arpa/inet.h>#include <ctype.h>#include <openssl/crypto.h>#include <openssl/ssl.h>#include <openssl/err.h>#include <openssl/rand.h>#define DEBUG 1/********************************************功能：搜索字符串右边起的第一个匹配字符********************************************/char *Rstrchr(char *s, char x){ int i = strlen(s); if (!(*s)) return 0; while (s[i - 1]) if (strchr(s + (i - 1), x)) return (s + (i - 1)); else i--; return 0;}/**************************************************************功能：从字符串src中分析出网站地址和端口，并得到用户要下载的文件***************************************************************/void GetHost(char *src, char *web, char *file, int *port){ char *pA; char *pB; memset(web, 0, sizeof(web)); memset(file, 0, sizeof(file)); *port = 0; if (!(*src)) return; pA = src; if (!strncmp(pA, "http://", strlen("http://"))) pA = src + strlen("http://"); else if (!strncmp(pA, "https://", strlen("https://"))) pA = src + strlen("https://"); pB = strchr(pA, '/'); if (pB) { memcpy(web, pA, strlen(pA) - strlen(pB)); if (pB + 1) { memcpy(file, pB + 1, strlen(pB) - 1); file[strlen(pB) - 1] = 0; } } else memcpy(web, pA, strlen(pA)); if (pB) web[strlen(pA) - strlen(pB)] = 0; else web[strlen(pA)] = 0; pA = strchr(web, ':'); if (pA) *port = atoi(pA + 1); else *port = 443;}/************关于本文档*********************************************filename: https-client.c*purpose: 演示HTTPS客户端编程方法*wrote by: zhoulifa(zhoulifa@163.com) 周立发(http://zhoulifa.bokee.com)Linux爱好者 Linux知识传播者 SOHO族 开发者 最擅长C语言*date time:2007-01-30 20:06*Note: 任何人可以任意复制代码并运用这些文档，当然包括你的商业用途* 但请遵循GPL*Thanks to:Google*Hope:希望越来越多的人贡献自己的力量，为科学技术发展出力* 科技站在巨人的肩膀上进步更快！感谢有开源前辈的贡献！*********************************************************************/int main(int argc, char *argv[]){ int sockfd, ret; char buffer[1024]; struct sockaddr_in server_addr; struct hostent *host; int portnumber, nbytes; char host_addr[256]; char host_file[1024]; char local_file[256]; FILE *fp; char request[1024]; int send, totalsend; int i; char *pt; SSL *ssl; SSL_CTX *ctx; if (argc != 2) { if (DEBUG) fprintf(stderr, "Usage:%s webpage-address/a/n", arv[0]); exit(1); } if (DEBUG) printf("parameter.1 is: %s/n", argv[1]); GetHost(argv[1], host_addr, host_file, &portnumber); /*分析网址、端口、文件名等 */ if (DEBUG) printf("webhost:%s/n", host_addr); if (DEBUG) printf("hostfile:%s/n", host_file); if (DEBUG) printf("portnumber:%d/n/n", portnumber); if ((host = gethostbyname(host_addr)) == NULL) { /*取得主机IP地址 */ if (DEBUG) fprintf(stderr, "Gethostname error, %s/n", strerror(errno)); exit(1); } /* 客户程序开始建立 sockfd描述符 */ if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) { /*建立SOCKET连接 */ if (DEBUG) fprintf(stderr, "Socket Error:%s/a/n", strerror(errno)); exit(1); } /* 客户程序填充服务端的资料 */ bzero(&server_addr, sizeof(server_addr)); server_addr.sin_family = AF_INET; server_addr.sin_port = htons(portnumber); server_addr.sin_addr = *((struct in_addr *) host->h_addr); /* 客户程序发起连接请求 */ if (connect(sockfd, (struct sockaddr *) (&server_addr), sizeof(struct sockaddr)) == -1) { /*连接网站 */ if (DEBUG) fprintf(stderr, "Connect Error:%s/a/n", strerror(errno)); exit(1); } /* SSL初始化 */ SSL_library_init(); SSL_load_error_strings(); ctx = SSL_CTX_new(SSLv23_client_method()); if (ctx == NULL) { ERR_print_errors_fp(stderr); exit(1); } ssl = SSL_new(ctx); if (ssl == NULL) { ERR_print_errors_fp(stderr); exit(1); } /* 把socket和SSL关联 */ ret = SSL_set_fd(ssl, sockfd); if (ret == 0) { ERR_print_errors_fp(stderr); exit(1); } RAND_poll(); while (RAND_status() == 0) { unsigned short rand_ret = rand() % 65536; RAND_seed(&rand_ret, sizeof(rand_ret)); } ret = SSL_connect(ssl); if (ret != 1) { ERR_print_errors_fp(stderr); exit(1); } sprintf(request, "GET /%s HTTP/1.1/r/nAccept: */*/r/nAccept-Language: zh-cn/r/n/User-Agent: Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0)/r/n/Host: %s:%d/r/nConnection: Close/r/n/r/n", host_file, host_addr, portnumber); if (DEBUG) printf("%s", request); /*准备request，将要发送给主机 */ /*取得真实的文件名 */ if (host_file && *host_file) pt = Rstrchr(host_file, '/'); else pt = 0; memset(local_file, 0, sizeof(local_file)); if (pt && *pt) { if ((pt + 1) && *(pt + 1)) strcpy(local_file, pt + 1); else memcpy(local_file, host_file, strlen(host_file) - 1); } else if (host_file && *host_file) strcpy(local_file, host_file); else strcpy(local_file, "index.html"); if (DEBUG) printf("local filename to write:%s/n/n", local_file); /*发送https请求request */ send = 0; totalsend = 0; nbytes = strlen(request); while (totalsend < nbytes) { send = SSL_write(ssl, request + totalsend, nbytes - totalsend); if (send == -1) { if (DEBUG) ERR_print_errors_fp(stderr); exit(0); } totalsend += send; if (DEBUG) printf("%d bytes send OK!/n", totalsend); } fp = fopen(local_file, "a"); if (!fp) { if (DEBUG) printf("create file error! %s/n", strerror(errno)); return 0; } if (DEBUG) printf("/nThe following is the response header:/n"); i = 0; /* 连接成功了，接收https响应，response */ while ((nbytes = SSL_read(ssl, buffer, 1)) == 1) { if (i < 4) { if (buffer[0] == '/r' || buffer[0] == '/n') i++; else i = 0; if (DEBUG) printf("%c", buffer[0]);< /*把https头信息打印在屏幕上 */ } else { fwrite(buffer, 1, 1, fp); /*将https主体信息写入文件 */ i++; if (i % 1024 == 0) fflush(fp); /*每1K时存盘一次 */ } } fclose(fp); /* 结束通讯 */ ret = SSL_shutdown(ssl); if (ret != 1) { ERR_print_errors_fp(stderr); exit(1); } close(sockfd); SSL_free(ssl); SSL_CTX_free(ctx); ERR_free_strings(); exit(0);} |
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