#include "../common/common.c"
#define NAME "net3"
#define UID 996
#define GID 996
#define PORT 2996
/*
* Extract a null terminated string from the buffer
*/
int get_string(char **result, unsigned char *buffer, u_int16_t len)
{
unsigned char byte;
byte = *buffer;
if(byte > len) errx(1, "badly formed packet");
*result = malloc(byte);
strcpy(*result, buffer + 1);
return byte + 1;
}
/*
* Check to see if we can log into the host
*/
int login(unsigned char *buffer, u_int16_t len)
{
char *resource, *username, *password;
int deduct;
int success;
if(len < 3) errx(1, "invalid login packet length");
resource = username = password = NULL;
deduct = get_string(&resource, buffer, len);
deduct += get_string(&username, buffer+deduct, len-deduct);
deduct += get_string(&password, buffer+deduct, len-deduct);
success = 0;
success |= strcmp(resource, "net3");
success |= strcmp(username, "awesomesauce");
success |= strcmp(password, "password");
free(resource);
free(username);
free(password);
return ! success;
}
void send_string(int fd, unsigned char byte, char *string)
{
struct iovec v[3];
u_int16_t len;
int expected;
len = ntohs(1 + strlen(string));
v[0].iov_base = &len;
v[0].iov_len = sizeof(len);
v[1].iov_base = &byte;
v[1].iov_len = 1;
v[2].iov_base = string;
v[2].iov_len = strlen(string);
expected = sizeof(len) + 1 + strlen(string);
if(writev(fd, v, 3) != expected) errx(1, "failed to write correct amount of bytes");
}
void run(int fd)
{
u_int16_t len;
unsigned char *buffer;
int loggedin;
while(1) {
nread(fd, &len, sizeof(len));
len = ntohs(len);
buffer = malloc(len);
if(! buffer) errx(1, "malloc failure for %d bytes", len);
nread(fd, buffer, len);
switch(buffer[0]) {
case 23:
loggedin = login(buffer + 1, len - 1);
send_string(fd, 33, loggedin ? "successful" : "failed");
break;
default:
send_string(fd, 58, "what you talkin about willis?");
break;
}
}
}
int main(int argc, char **argv, char **envp)
{
int fd;
char *username;
/* Run the process as a daemon */
background_process(NAME, UID, GID);
/* Wait for socket activity and return */
fd = serve_forever(PORT);
/* Set the client socket to STDIN, STDOUT, and STDERR */
set_io(fd);
/* Don't do this :> */
srandom(time(NULL));
run(fd);
}