int echoServer(int argc, char** argv) {
int listenfd, connfd, port, clientlen;
struct sockaddr_in clientaddr;
struct hostent *hp;
char* haddrp;
if (argc != 2) {
fprintf(stderr, "usage: %s <port>\n", argv[0]);
exit(0);
}
port = atoi(argv[1]);
listenfd = Open_listenfd(port);
while (1) {
clientlen = sizeof(clientaddr);
connfd = Accept(listenfd, (SA *)&clientaddr, (socklen_t *)&clientlen);
hp = Gethostbyaddr((const char *)&clientaddr.sin_addr.s_addr,
sizeof(clientaddr.sin_addr.s_addr), AF_INET);
haddrp = inet_ntoa(clientaddr.sin_addr);
printf("server connected to %s (%s)\n", hp->h_name, haddrp);
echo(connfd);
Close(connfd);
}
exit(0);
}
int main(int argc, char **argv)
{
char **pp;
struct in_addr addr;
struct hostent *hostp;
if (argc != 2) {
fprintf(stderr, "usage: %s <domain name or dotted-decimal>\n", argv[0]);
exit(0);
}
if (inet_aton(argv[1], &addr) != 0)
hostp = Gethostbyaddr((const char *)&addr, sizeof(addr), AF_INET); //AF_INET等于0,指的是使用IPV4
else
hostp = Gethostbyname(argv[1]);
printf("official hostname: %s\n", hostp->h_name);
for (pp = hostp->h_aliases; *pp != NULL; pp++) { //aliase->别名
printf("alias: %s\n", *pp);
}
for (pp = hostp->h_addr_list; *pp != NULL; pp++) {
//printf("%s\n", *pp);
addr.s_addr = ((struct in_addr *)*pp)->s_addr; //*pp 是 char *类型
/* expected ‘struct in_addr’ but argument is of type ‘struct in_addr *’ */
printf("address: %s\n", inet_ntoa(addr));
}
exit(0);
}
// call(2, localhost)
int retrievesAndPrintsDNSHostEntry(int argc, char** argv) {
char** pp;
struct in_addr addr;
struct hostent *hostp;
if (argc != 2) {
fprintf(stderr, "usage: %s <domain name or dotted-decimal>\n", argv[0]);
exit(0);
}
if (inet_aton(argv[1], &addr) != 0) {
hostp = Gethostbyaddr((const char*)&addr, sizeof(addr), AF_INET);
} else {
hostp = Gethostbyname(argv[1]);
}
printf("official hostname: %s\n", hostp->h_name);
for (pp = hostp->h_aliases; *pp != NULL; pp++) {
printf("alias: %s\n", *pp);
}
for (pp = hostp->h_addr_list; *pp != NULL; pp++) {
addr.s_addr = ((struct in_addr *) *pp)->s_addr;
printf("address: %s\n", inet_ntoa(addr));
}
}
int main(int argc, char **argv)
{
int listenfd, connfd, port;
socklen_t clientlen = sizeof(struct sockaddr_in);
struct sockaddr_in clientaddr;
struct hostent *hp;
char *haddrp;
if (argc != 2) {
fprintf(stderr, "usage: %s <port>\n", argv[0]);
exit(0);
}
port = atoi(argv[1]);
Signal(SIGCHLD, sigchld_handler);
listenfd = Open_listenfd(port);
while (1) {
connfd = Accept(listenfd, (SA *)&clientaddr, &clientlen);
if (Fork() == 0) {
Close(listenfd);
echo(connfd);
hp = Gethostbyaddr((const char *)&clientaddr.sin_addr.s_addr, sizeof(clientaddr.sin_addr.s_addr), AF_INET);
haddrp = inet_ntoa(clientaddr.sin_addr);
printf("server connected to %s (%s)\n", hp->h_name, haddrp);
Close(connfd);
exit(0);
}
Close(connfd);
}
exit(0);
}
int main(int argc, char **argv)
{
int listenfd, connfd, port, clientlen;
struct sockaddr_in clientaddr;
struct hostent *hp;
char *haddrp;
short client_port;
if (argc != 2) {
fprintf(stderr, "usage: %s <port>\n", argv[0]);
exit(0);
}
port = atoi(argv[1]);
listenfd = Open_listenfd(port);
while (1) {
clientlen = sizeof(clientaddr);
connfd = Accept(listenfd, (SA *)&clientaddr, &clientlen);
/* determine the domain name and IP address of the client */
hp = Gethostbyaddr((const char *)&clientaddr.sin_addr.s_addr,
sizeof(clientaddr.sin_addr.s_addr), AF_INET);
haddrp = inet_ntoa(clientaddr.sin_addr);
client_port = ntohs(clientaddr.sin_port);
printf("server connected to %s (%s), port %d\n",
hp->h_name, haddrp, client_port);
echo(connfd, "");
printf("Connection closed\n");
Close(connfd);
}
exit(0);
}
int main(int argc, char *argv[]) {
char **pp; /* cursor */
struct in_addr addr; /* holds the IP in integer form */
struct hostent *hostp; /* holds various info about the server */
if (argc != 2) {
fprintf(stderr, "usage: %s <domain name or dotted-decimal>\n", argv[0]);
return 0;
}
/*inet_aton will convert a dotted decimal into an in_addr. If the user has
given a named form, this will be 0, and we'll use Gethostbyname. */
if (inet_aton(argv[1], &addr) != 0)
hostp = Gethostbyaddr((const char*) &addr, sizeof(addr), AF_INET);
else
hostp = Gethostbyname(argv[1]);
printf("Official hostname: %s\n", hostp->h_name);
for (pp=hostp->h_aliases; *pp != NULL; ++pp)
printf("alias: %s\n", *pp);
for (pp = hostp->h_addr_list; *pp != NULL; ++pp) {
addr.s_addr = ((struct in_addr*)*pp)->s_addr;
printf("address: %s\n", inet_ntoa(addr));
}
return 0;
}
int main(int argc, char **argv)
{
int port = atoi(argv[1]);
struct sockaddr_in clientaddr;
int clientlen=sizeof(clientaddr);
pthread_t tid;
int listenfd = Open_listenfd(port);
while (1) {
int *connfdp = Malloc(sizeof(int));
struct hostent *hp;
char *haddrp;
int client_port;
*connfdp = Accept(listenfd, (SA *) &clientaddr, &clientlen);
/* determine the domain name and IP address of the client */
hp = Gethostbyaddr((const char *)&clientaddr.sin_addr.s_addr,
sizeof(clientaddr.sin_addr.s_addr), AF_INET);
haddrp = inet_ntoa(clientaddr.sin_addr);
client_port = ntohs(clientaddr.sin_port);
printf("Server connected to %s (%s), port %d\n",
hp->h_name, haddrp, client_port);
Pthread_create(&tid, NULL, echo_thread, connfdp);
}
}
int main(int argc, char **argv) {
int listenfd, connfd;
socklen_t clientlen = sizeof(struct sockaddr_in);
struct sockaddr_in clientaddr;
user* u;
/* Init node and set port accoriding to configue file */
init_node(argc, argv);
/* Init the linked list of channel and the table of user */
init_channel();
init_user();
/* Init server socket and set it as unblocked */
listenfd = init_unblocking_server_socket(curr_node_config_entry->irc_port);
/* connect to local daemon */
local_client_fd = socket_connect(curr_node_config_entry->ipaddr,curr_node_config_entry->local_port);
/* Init struct pool */
init_pool();
add_listen_fd(listenfd);
while (1) {
/* Wait for listening/connected descriptor(s) to become ready */
p.ready_set = p.read_set;
p.nready = Select(p.maxfd+1, &p.ready_set, NULL, NULL, NULL);
/* If listening descriptor ready, add new client to pool */
if (FD_ISSET(listenfd, &p.ready_set)) {
connfd = Accept(listenfd, (SA *)&clientaddr, &clientlen);
/* create a user struct for the connect fd */
u = (user*) Calloc(1,sizeof(user));
user_table[connfd] = u;
/*set server_name and host_name for user */
u->host_name = strdup(Gethostbyaddr((const char*)&clientaddr.sin_addr,sizeof(clientaddr.sin_addr),AF_INET)->h_name);
u->server_name = strdup(Gethostbyname("localhost")->h_name);
add_client(connfd);
}
/* Echo a text line from each ready connected descriptor */
check_clients();
}
}
int main(int argc, char* argv[])
{
int listenfd, connfd;
socklen_t clientlen;
struct sockaddr_in clientaddr;
struct hostent *hp;
char *haddrp;
fd_set read_set, ready_set;
if (argc != 2) {
more_error("usage: %s <port>", argv[0]);
}
Signal(SIGCHLD, sigchld_handler);
listenfd = Open_listenfd(atoi(argv[1]));
FD_ZERO(&read_set);
FD_SET(STDIN_FILENO, &read_set);
FD_SET(listenfd, &read_set);
while (1)
{
ready_set = read_set;
Select(listenfd + 1, &ready_set, NULL, NULL, NULL);
if (FD_ISSET(STDIN_FILENO, &ready_set)) {
command();
} else if (FD_ISSET(listenfd, &ready_set)) {
clientlen = sizeof(clientaddr);
connfd = Accept(listenfd, (SA *)&clientaddr, &clientlen);
/* printf("%#x\n", ntohl(clientaddr.sin_addr.s_addr)); */
hp = Gethostbyaddr((const void *)&clientaddr.sin_addr.s_addr,
sizeof(clientaddr.sin_addr.s_addr), AF_INET);
haddrp = inet_ntoa(clientaddr.sin_addr);
printf("Server connected to %s [%s]\n", hp->h_name, haddrp);
if (Fork() == 0) {
Close(listenfd);
echo(connfd);
Close(connfd);
exit(0);
}
Close(connfd);
}
}
return 0;
}
void servertest(char *port) {
char *request, *hostname, *response, *client_ip_address;
struct sockaddr_in clientaddr;
struct hostent *hp;
int clientlen, connfd;
// start listening and enter infinite listening loop
int listenfd = Open_listenfd(port);
while (1) {
// accept a connection
clientlen = sizeof(clientaddr);
connfd = Accept(listenfd, (SA *)&clientaddr, &clientlen);
// get some information from the client
hp = Gethostbyaddr((const char *)&clientaddr.sin_addr.s_addr,
sizeof(clientaddr.sin_addr.s_addr), AF_INET);
client_ip_address = inet_ntoa(clientaddr.sin_addr);
// read the request from the end-user
request = read_until(connfd, "\r\n\r\n\0");
// Store the hostname from the request
hostname = parseRequest(request);
// printf("S-Parse result:%s", hostname);
if (hostname) {
// Pass on the client's request
response = clienttest(hostname, request);
// printf("S-Response result:\n%s\n", response);
//check that the response isn't empty (end-server responded)
// respond to the end-user
Rio_writen(connfd, response, strlen(response));
// writeLogEntry (only if there was a response)
if (strcmp(response, "") != 0) {
writeLogEntry(client_ip_address, hostname, strlen(response));
// printf("S-Wrote log.\n");
}
}
// Finished, close connection
Close(connfd);
// Free the buffers except
// client_ip_address is statically managed by inet_ntoa
free(request);
free(hostname);
free(response);
}
}
/*
* main - Main routine for the proxy program runs the proxy server
*/
int main(int argc, char **argv)
{
int listenfd, connfd, clientlen, ID=0;
struct sockaddr_in clientaddr;
struct sockaddr_in * passClientaddr=&clientaddr;
struct hostent *hp;
char *haddrp;
pthread_t tid[MAXTREAD];
/* Check arguments */
if(argc != 2){
fprintf(stderr, "Usage: %s <port number>\n", argv[0]);
exit(0);
}
signal(SIGPIPE, SIG_IGN);
listenfd=Open_listenfd(atoi(argv[1]));
while(1){
clientlen =sizeof(clientaddr);
connfd = Accept(listenfd, (SA *)&clientaddr,(unsigned int *)&clientlen);
//Determine the domain name and IP address of the client then send print statement
hp=Gethostbyaddr((const char *)&clientaddr.sin_addr.s_addr, sizeof(clientaddr.sin_addr.s_addr), AF_INET);
haddrp =inet_ntoa(clientaddr.sin_addr);
printf("Thread %d: Receieved request from %s (%s):\n",ID,hp->h_name,haddrp);
//make and set known data to thread
struct treadInfo thread;
thread.clientfd=connfd;
rio_readinitb(&thread.rioWithClient,thread.clientfd);
thread.ID=ID;
thread.sockaddr=*passClientaddr;
//create new thread
Pthread_create(&tid[ID], NULL,doit,&(void *)thread);
//add one to ID count
ID++;
}
exit(0);
}
int main(int argc, char **argv)
{
int listenfd, connfd, port;
socklen_t clientlen;
struct sockaddr_in clientaddr;
struct hostent *hp;
char *haddrp;
if (argc != 2) {
fprintf(stderr, "usage: %s <port>\n", argv[0]);
exit(0);
}
port = atoi(argv[1]);
// read in the first line from the client
readconfig();
readcommand();
//size_t n;
char buf[128];
char user[40];
char pass[40];
rio_t rio;
listenfd = Open_listenfd(port);
clientlen = sizeof(clientaddr);
connfd = Accept(listenfd, (SA *)&clientaddr, &clientlen);
Rio_readinitb(&rio, connfd);
//read username and password from client. Each individual line.
Rio_readlineb(&rio, user, 40); //line:netp:echo:eof
Rio_readlineb(&rio, pass, 40);
int login = 0;
int ctr = 0;
strtok(pass, "\n");
strtok(user, "\n");
while(ctr < 128)
{
if(strcmp(userpass[0][ctr], user) == 0 && (strcmp(userpass[1][ctr], pass)) == 0)
{
login++;
}
ctr++;
}
if (login == 0)
{
printf("User %s Failed logging in\n", user);
Rio_writen(connfd, "Login Failed\n", 14);
Close(connfd);
exit(0);
}
else
{
// Determine the domain name and IP address of the client
hp = Gethostbyaddr((const char *)&clientaddr.sin_addr.s_addr,
sizeof(clientaddr.sin_addr.s_addr), AF_INET);
haddrp = inet_ntoa(clientaddr.sin_addr);
printf("server connected to %s (%s)\n", hp->h_name, haddrp);
printf("User %s logging in from %s at TCP Port %d\n", user, haddrp, port);
printf("User %s successfully logged in.\n", user);
Rio_writen(connfd, "Login Successful\n", 17);//Warning if this isn't 17 it will affect every Rio_writen after this
ctr = 0;
while(ctr == 0)
{
//reads your command from the client
Rio_readlineb(&rio, buf, 128);
strtok(buf, "\n");
printf("User %s sent the commandline %s to be executed\n", user, buf);
if(strcmp(buf, "quit") == 0)
{
printf("Logged out\n");
Rio_writen(connfd, "quit\n", 5);// Same warning as above
ctr++;
}
else
{
char *file;
char *command;
char *thirdinput;
char *str = buf; //buf = /bin/cat echo.c
command = strtok(str, " "); //command = /bin/cat
file = strtok(NULL, " "); //file = echo.c
thirdinput = strtok(NULL, " ");
int usecommand = 0;
int ctr2 = 0;
while(ctr2 < 128)
{
if(strcmp(execcom[ctr2], command) == 0)
{
usecommand++;
}
ctr2++;
}
if(usecommand == 0)
{
Rio_writen(connfd, "nocomm\n", 7);// Same warning as above
printf("Cannot execute '%s' on this server.\n", buf);
}
else
{
printf("Forking/Execing the command '%s' on behalf of %s\n", buf, user);
char buffer[MAXLINE];
int pipefd[2];
pipe(pipefd);
pid_t pid = fork();
if (!pid)
{
close(pipefd[0]);
dup2(pipefd[1], 1);
dup2(pipefd[1], 2);
close(pipefd[1]);
char *env[] = {0};
char *arg[] = {command, file, thirdinput, NULL};
//call your executable in your current directory
execve(command, arg, env);
}
else if (pid == -1)
{
perror("fork");
}
else
{
//parent
close(pipefd[1]);
while (read(pipefd[0], buffer, sizeof(buffer)) != 0)
{
}
}
int status;
wait(&status);
//sends out the string results of exec.
Rio_writen(connfd, buffer, strlen(buffer));
//we use this as a counter to tell the client that we have sent everything over.
Rio_writen(connfd, "exec\n", 5);// Same warning as above
int ctr2 = 0;
while(ctr2 < MAXLINE)
{
buffer[ctr2] = 0;
ctr2++;
}
}
}
}
}
Close(connfd);
exit(0);
}
