c語言利用SMTP協議傳送郵件
阿新 • • 發佈：2019-01-02
#ifdef WIN32 #include <windows.h> #include <stdio.h> #else #include <stdio.h> #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <errno.h> #include <unistd.h> #include <sys/time.h> #endif struct data6 { unsigned int d4:6; unsigned int d3:6; unsigned int d2:6; unsigned int d1:6; }; // 協議中加密部分使用的是base64方法 char con628(char c6); void base64(char *dbuf,char *buf128,int len); void sendemail(char *email,char *body); int open_socket(struct sockaddr *addr); int main() { char email[] = "[email protected]"; char body[] = "From: \"lucy\"<[email protected]>\r\n" "To: \"dasiy\"<[email protected]>\r\n" "Subject: Hello\r\n\r\n" "Hello World, Hello Email!"; sendemail(email, body); return 0; } char con628(char c6) { char rtn = '\0'; if (c6 < 26) rtn = c6 + 65; else if (c6 < 52) rtn = c6 + 71; else if (c6 < 62) rtn = c6 - 4; else if (c6 == 62) rtn = 43; else rtn = 47; return rtn; } // base64的實現 void base64(char *dbuf, char *buf128, int len) { struct data6 *ddd = NULL; int i = 0; char buf[256] = {0}; char *tmp = NULL; char cc = '\0'; memset(buf, 0, 256); strcpy(buf, buf128); for(i = 1; i <= len/3; i++) { tmp = buf+(i-1)*3; cc = tmp[2]; tmp[2] = tmp[0]; tmp[0] = cc; ddd = (struct data6 *)tmp; dbuf[(i-1)*4+0] = con628((unsigned int)ddd->d1); dbuf[(i-1)*4+1] = con628((unsigned int)ddd->d2); dbuf[(i-1)*4+2] = con628((unsigned int)ddd->d3); dbuf[(i-1)*4+3] = con628((unsigned int)ddd->d4); } if(len%3 == 1) { tmp = buf+(i-1)*3; cc = tmp[2]; tmp[2] = tmp[0]; tmp[0] = cc; ddd = (struct data6 *)tmp; dbuf[(i-1)*4+0] = con628((unsigned int)ddd->d1); dbuf[(i-1)*4+1] = con628((unsigned int)ddd->d2); dbuf[(i-1)*4+2] = '='; dbuf[(i-1)*4+3] = '='; } if(len%3 == 2) { tmp = buf+(i-1)*3; cc = tmp[2]; tmp[2] = tmp[0]; tmp[0] = cc; ddd = (struct data6 *)tmp; dbuf[(i-1)*4+0] = con628((unsigned int)ddd->d1); dbuf[(i-1)*4+1] = con628((unsigned int)ddd->d2); dbuf[(i-1)*4+2] = con628((unsigned int)ddd->d3); dbuf[(i-1)*4+3] = '='; } return; } // 傳送郵件 void sendemail(char *email, char *body) { int sockfd = 0; struct sockaddr_in their_addr = {0}; char buf[1500] = {0}; char rbuf[1500] = {0}; char login[128] = {0}; char pass[128] = {0}; #ifdef WIN32 WSADATA WSAData; WSAStartup(MAKEWORD(2, 2), &WSAData); #endif memset(&their_addr, 0, sizeof(their_addr)); their_addr.sin_family = AF_INET; their_addr.sin_port = htons(25); their_addr.sin_addr.s_addr = inet_addr("112.90.141.71");//qq smtp 伺服器 // 連線郵件伺服器，如果連線後沒有響應，則2 秒後重新連線 sockfd = open_socket((struct sockaddr *)&their_addr); memset(rbuf,0,1500); while(recv(sockfd, rbuf, 1500, 0) == 0) { printf("reconnect...\n"); Sleep(2); //close(sockfd); sockfd = open_socket((struct sockaddr *)&their_addr); memset(rbuf,0,1500); } printf("%s\n", rbuf); // EHLO memset(buf, 0, 1500); sprintf(buf, "EHLO abcdefg-PC\r\n"); send(sockfd, buf, strlen(buf), 0); memset(rbuf, 0, 1500); recv(sockfd, rbuf, 1500, 0); printf("%s\n", rbuf); // AUTH LOGIN memset(buf, 0, 1500); sprintf(buf, "AUTH LOGIN\r\n"); send(sockfd, buf, strlen(buf), 0); printf("%s\n", buf); memset(rbuf, 0, 1500); recv(sockfd, rbuf, 1500, 0); printf("%s\n", rbuf); // USER memset(buf, 0, 1500); sprintf(buf,"12345678");//你的qq號 memset(login, 0, 128); base64(login, buf, strlen(buf)); sprintf(buf, "%s\r\n", login); send(sockfd, buf, strlen(buf), 0); printf("%s\n", buf); memset(rbuf, 0, 1500); recv(sockfd, rbuf, 1500, 0); printf("%s\n", rbuf); // PASSWORD sprintf(buf, "qqpassword");//你的qq密碼 memset(pass, 0, 128); base64(pass, buf, strlen(buf)); sprintf(buf, "%s\r\n", pass); send(sockfd, buf, strlen(buf), 0); printf("%s\n", buf); memset(rbuf, 0, 1500); recv(sockfd, rbuf, 1500, 0); printf("%s\n", rbuf); // MAIL FROM memset(buf, 0, 1500); sprintf(buf, "MAIL FROM: <[email protected]>\r\n"); send(sockfd, buf, strlen(buf), 0); memset(rbuf, 0, 1500); recv(sockfd, rbuf, 1500, 0); printf("%s\n", rbuf); // RCPT TO 第一個收件人 sprintf(buf, "RCPT TO:<%s>\r\n", email); send(sockfd, buf, strlen(buf), 0); memset(rbuf, 0, 1500); recv(sockfd, rbuf, 1500, 0); printf("%s\n", rbuf); // DATA 準備開始傳送郵件內容 sprintf(buf, "DATA\r\n"); send(sockfd, buf, strlen(buf), 0); memset(rbuf, 0, 1500); recv(sockfd, rbuf, 1500, 0); printf("%s\n", rbuf); // 傳送郵件內容，\r\n.\r\n內容結束標記 sprintf(buf, "%s\r\n.\r\n", body); send(sockfd, buf, strlen(buf), 0); memset(rbuf, 0, 1500); recv(sockfd, rbuf, 1500, 0); printf("%s\n", rbuf); // QUIT sprintf(buf, "QUIT\r\n"); send(sockfd, buf, strlen(buf), 0); memset(rbuf, 0, 1500); recv(sockfd, rbuf, 1500, 0); printf("%s\n", rbuf); // VC2005 需要使用 closesocket(sockfd); // close(sockfd); #ifdef WIN32 WSACleanup(); #endif return; } // 開啟TCP Socket連線 int open_socket(struct sockaddr *addr) { int sockfd = 0; sockfd=socket(PF_INET, SOCK_STREAM, 0); if(sockfd < 0) { fprintf(stderr, "Open sockfd(TCP) error!\n"); exit(-1); } if(connect(sockfd, addr, sizeof(struct sockaddr)) < 0) { fprintf(stderr, "Connect sockfd(TCP) error!\n"); exit(-1); } return sockfd; }