Linux Socket实现的FTP客户端/服务器程序

/********************************************************** ** File Name:client.c * Author:Wangmeng * Data:2010.06.01 **********************************************************/ #include<stdio.h> #include<unistd.h> #include<stdlib.h> #include<limits.h> #include<string.h> #include<ctype.h> #include<sys/types.h> #include<sys/socket.h> #include<sys/stat.h> #include<netdb.h> #include<netinet/in.h> #include<arpa/inet.h> #include<errno.h> #include<dirent.h> #define MAX_INPUT_SIZE 254 #define LOCAL_IP "127.0.0.1" #define SERVER_PORT 2049 #define DATA_PORT 2048 #define FILEBUF_SIZE 1024 #define TYPE_I 0 #define TYPE_A 1 int TYPE = 0; const char *MODE[] = {"BINARY","ASCII"}; char buffer[FILEBUF_SIZE]; char line_in[MAX_INPUT_SIZE+1]; char *server_ip, *local_ip; char port_addr[24] = ""; int server_port, local_port; int server_sock, client_sock = -1, data_sock; int z = 0; struct sockaddr_in server_addr, client_addr, data_addr; struct hostent *server_host; /* Search through str looking for what. Replace any what with the contents of by. Do not let the string get longer than max_length. */ int replace(char *str, char *what, char *by, int max_length); //send msg to server void send_msg(char *command, char *msg, int flag); //some functions void help_info(); void user_login(); void command_quit(); void command_syst(); void command_type(); void command_pwd(); void command_cd(); int command_port(); int data_conn(char *ip, int port); void command_list(); void command_get(char *filename); void command_put(char *filename); int main(int argv, char **argc) { if(argv == 1) { server_ip = LOCAL_IP; server_port = SERVER_PORT; } else if(argv == 2) { server_ip = argc[1]; server_port = SERVER_PORT; } else if(argv == 3) { server_ip = argc[1]; server_port = atoi(argc[2]); } //connect to the ftp server server_host = gethostbyname(server_ip); if(server_host == (struct hostent *)NULL) { printf(">gethostbyname failed\n"); exit(1); } //setup the port for the connection memset(&server_addr, 0, sizeof(server_addr)); server_addr.sin_family = AF_INET; memcpy(&server_addr.sin_addr, server_host->h_addr, server_host->h_length); server_addr.sin_port = htons(server_port); //get the socket server_sock = socket(PF_INET, SOCK_STREAM, 0); if(server_sock < 0) { printf(">error on socket()\n"); exit(1); } //connect to the server if(connect(server_sock, (struct sockaddr *)&server_addr, sizeof(server_addr)) < 0) { printf(">error on connect()\n"); close(server_sock); exit(1); } //connect to the ftp server successful printf(">Connected to %s:%d\n", server_ip, server_port); z = read(server_sock, buffer, sizeof(buffer)); buffer[z-2] = 0; printf("%s\n", buffer); //printf("z = %d, buffer is '%s'\n",z,buffer); //login user_login(); while(1) { printf(">"); fgets(line_in, MAX_INPUT_SIZE, stdin); line_in[strlen(line_in)-1] = '\0'; if(strncmp("quit", line_in, 4) == 0) { command_quit(); break; } else if((strncmp("?", line_in, 1) == 0) || (strncmp("help", line_in, 4) == 0)) { help_info(); } else if(strncmp("syst", line_in, 4) == 0) { command_syst(); } else if(strncmp("type", line_in, 4) == 0) { command_type(); } else if(strncmp("pwd", line_in, 3) == 0) { command_pwd(); } else if(strncmp("cd", line_in, 2) == 0) { command_cd(); } else if(strncmp("port", line_in, 4) == 0) { command_port(); } else if((strncmp("ls", line_in, 4) == 0) || (strncmp("dir", line_in, 3) == 0)) { command_list(); } else if(strncmp("get", line_in, 3) == 0) { command_get(&line_in[4]); } else if(strncmp("put", line_in, 3) == 0) { command_put(&line_in[4]); } } close(server_sock); return 0; } /* Search through str looking for what. Replace any what with the contents of by. Do not let the string get longer than max_length. */ int replace(char *str, char *what, char *by, int max_length) { char *foo, *bar = str; int i = 0; int str_length, what_length, by_length; /* do a sanity check */ if (! str) return 0; if (! what) return 0; if (! by) return 0; what_length = strlen(what); by_length = strlen(by); str_length = strlen(str); foo = strstr(bar, what); /* keep replacing if there is somethign to replace and it will no over-flow */ while ( (foo) && ( (str_length + by_length - what_length) < (max_length - 1) ) ) { bar = foo + strlen(by); memmove(bar, foo + strlen(what), strlen(foo + strlen(what)) + 1); memcpy(foo, by, strlen(by)); i++; foo = strstr(bar, what); str_length = strlen(str); } return i; } //send msg to server void send_msg(char *command, char *msg, int flag) { char reply[MAX_INPUT_SIZE+1]; if(flag == 0) sprintf(reply, "%s\r\n", command); else sprintf(reply, "%s %s\r\n", command, msg); write(server_sock, reply, strlen(reply)); printf("%d-->%s",strlen(reply), reply); return; } void help_info() { printf("?\tcd\tdir\tls\n"); printf("help\tsyst\ttype\tport\n"); printf("pwd\tget\tput\tquit\n"); } void user_login() { printf(">Name:"); fgets(line_in, MAX_INPUT_SIZE, stdin); line_in[strlen(line_in)-1] = '\0'; send_msg("USER", line_in, 1); z = read(server_sock, buffer, sizeof(buffer)); buffer[z-2] = 0; printf("%s\n", buffer); //printf("z = %d, buffer is '%s'\n",z,buffer); if(strncmp("331", buffer, 3) == 0) { printf(">Password:"); fgets(line_in, MAX_INPUT_SIZE, stdin); line_in[strlen(line_in)-1] = '\0'; send_msg("PASS", line_in, 1); z = read(server_sock, buffer, sizeof(buffer)); buffer[z-2] = 0; printf("%s\n", buffer); //printf("z = %d, buffer is '%s'\n",z,buffer); } line_in[0] = 0; command_syst(); return; } void command_syst() { send_msg("SYST", "", 0); z = read(server_sock, buffer, sizeof(buffer)); buffer[z-2] = 0; printf("%s\n", buffer); } void command_quit() { send_msg("QUIT", "", 0); z = read(server_sock, buffer, sizeof(buffer)); buffer[z-2] = 0; printf("%s\n", buffer); } void command_type() { char msg[2]; msg[1] = 0; if(strncmp("ascii", &line_in[5], 5) == 0) { msg[0] = 'A'; TYPE = TYPE_A; } else if(strncmp("binary", &line_in[5], 6) == 0) { msg[0] = 'I'; TYPE = TYPE_I; } send_msg("TYPE", msg, 1); z = read(server_sock, buffer, sizeof(buffer)); buffer[z-2] = 0; printf("%s\n", buffer); } void command_pwd() { send_msg("PWD", "", 0); z = read(server_sock, buffer, sizeof(buffer)); buffer[z-2] = 0; printf("%s\n", buffer); } void command_cd() { send_msg("CWD", &line_in[3], 1); z = read(server_sock, buffer, sizeof(buffer)); buffer[z-2] = 0; printf("%s\n", buffer); } int command_port() { if(client_sock < 0) { struct sockaddr_in local_addr; socklen_t local_addr_len = sizeof local_addr; memset(&local_addr, 0, sizeof local_addr); if(getsockname(server_sock, (struct sockaddr *)&local_addr, &local_addr_len) != 0) { printf("error when trying to get the local addr\n"); return -1; } local_ip = inet_ntoa(local_addr.sin_addr); local_port = local_addr.sin_port; printf("local addr %s:%d\n", local_ip, local_port); char client_port[8] = ""; sprintf(client_port, "%d.%d", (int)(local_port/256), (int)(1 + local_port - 256 * (int)(local_port/256))); sprintf(port_addr, "%s.%s", local_ip, client_port); replace(port_addr, ".", ",", 24); if(data_conn(local_ip, local_port + 1) == -1) return -1; } send_msg("PORT", port_addr, 1); z = read(server_sock, buffer, sizeof(buffer)); buffer[z-2] = 0; printf("%s\n", buffer); //accept an request socklen_t data_addr_len = sizeof data_addr; memset(&data_addr, 0, sizeof data_addr); data_sock = accept(client_sock, (struct sockaddr *)&data_addr, &data_addr_len); if(data_s