#include #include #include #include #ifdef AIX #include #endif #include #include #include #ifdef AIX #include #endif #include #include #include #include #include int http_sock, con_sock; int http_port = 80; struct sockaddr_in source; char *log_httpfile = NULL; char *homedir; int uid; int nouidcheck = 0; int debug = 0; int security = 1; void broken(void) { close(con_sock); log_http("SIGPIPE", ""); exit(0); } void closesock(int n) { close(con_sock); close(http_sock); log_http("SIGTERM", ""); exit(0); } void init_servconnection(void) { struct sockaddr_in server; /* Creation socket */ http_sock = socket(AF_INET, SOCK_STREAM, 0); if (http_sock < 0) { perror("socket"); exit(1); } signal(SIGTERM, closesock); signal(SIGPIPE, broken); signal(SIGCHLD, SIG_IGN); server.sin_family = AF_INET; server.sin_port = htons(http_port); server.sin_addr.s_addr = INADDR_ANY; if (bind(http_sock, (struct sockaddr *) & server, sizeof(server)) < 0) { perror("bind socket"); exit(1); } if (listen(http_sock, 1) < 0) { perror("listen"); exit(-1); } } void waitconnection(void) { int lg; lg = sizeof(struct sockaddr_in); con_sock = accept(http_sock, (struct sockaddr *) & source, &lg); if (con_sock <= 0) { perror("accept"); exit(-1); } } usage() { fprintf(stderr, "usage httpd [-DUs] [-l log_httpfile][-p port][-d homedir][-u uid]\n"); fprintf(stderr,"-d : default root http dir\n-s disable security\n"); fprintf(stderr,"-U : disable uid check\n-D : increment debug mode\n"); fprintf(stderr,"\n-s implies -U. -s enables absolute pathnames and the use of ~username\n"); fprintf(stderr,"Without -U (or -s) only files with the same UID is the process (or the one\nspecified by -u) can be read.\n"); exit(-1); } char rep_err_nget[] = "Error

Error 405

\ This server answer only to GET requests\n\n"; char rep_err_acc[] = "Error

Error 404

\ Not found - file doesn't exist or is read protected\n\n"; char rep_err_user[] = "Error

Error 404

\ Not found - username doesn't exist, or cannot be expanded\n\n"; log_http(char *action, char *item) { int fd; char logline[1024]; time_t tl; if (log_httpfile == NULL) return; tl = time(NULL); strcpy(logline, ctime(&tl)); logline[strlen(logline) - 1] = ' '; strcat(logline, inet_ntoa(source.sin_addr)); strcat(logline, " "); strcat(logline, action); strcat(logline, ":"); strcat(logline, item); strcat(logline, "\n"); fd = open(log_httpfile, O_WRONLY | O_APPEND | O_CREAT, 0600); if (fd < 0) { perror("open log file"); exit(-1); } write(fd, logline, strlen(logline)); close(fd); } serve_req(char *req) { char buff[1024]; char *username; struct passwd *spws; int fd, lg; char *filename, *c; char urlbuf[256]; char urlbuf2[256]; struct stat statres; int nfds; fd_set rfd, wfd, xfd; struct timeval timeout; int count=0; char file_default[32]; sprintf(file_default, "index.html"); FD_ZERO(&wfd); FD_ZERO(&xfd); FD_ZERO(&rfd); FD_SET(con_sock,&rfd ); nfds = FD_SETSIZE; timeout.tv_sec = 0; timeout.tv_usec = 100000; select(nfds, &rfd, &wfd, &xfd, &timeout); if (strcmp(strtok(req, " "), "GET") != 0) { write(con_sock, rep_err_nget, strlen(rep_err_nget)); log_http("error 405", req); return; } filename = strtok(NULL, " "); /* skip the initial slash */ filename++; /* if there isn't a file name, use the default of index.html */ if(!*filename) filename = file_default; strcpy(urlbuf, filename); if(security) { /* forbid ".." in the path */ c = filename; while (*c != '\0') if (c[0] == '.' && c[1] == '.') { write(con_sock, rep_err_acc, strlen(rep_err_acc)); log_http("error 404", filename); return; } else c++; } else { /* try to expand tildes to full usernames */ if(*filename=='~') { username = filename+1; c = filename; while(*c && (*c!='/')) c++; if(*c) { *c='\0'; c++; if(!*c) c = file_default; } else { c = file_default; } setpwent(); spws = getpwnam(username); if(!spws) { write(con_sock, rep_err_user, strlen(rep_err_user)); log_http("error 404", filename); return; } sprintf(urlbuf,"%s/%s",spws->pw_dir, c); filename = urlbuf; } } if(urlbuf[strlen(urlbuf)-1]=='/') { log_http("adding default",urlbuf); strcat(urlbuf,file_default); } fd = open(urlbuf, O_RDONLY); if (fd < 0) { write(con_sock, rep_err_acc, strlen(rep_err_acc)); log_http("cant open", urlbuf); return; } if (fstat(fd, &statres) < 0) { write(con_sock, rep_err_acc, strlen(rep_err_acc)); log_http("cant stat", urlbuf); close(fd); return; } if (S_ISDIR(statres.st_mode)) { log_http("is directory",urlbuf); strcat(urlbuf,"/"); strcat(urlbuf,file_default); close(fd); fd = open(urlbuf, O_RDONLY); if (fd < 0) { write(con_sock, rep_err_acc, strlen(rep_err_acc)); log_http("cant open",urlbuf); return; } if (fstat(fd, &statres) < 0) { write(con_sock, rep_err_acc, strlen(rep_err_acc)); log_http("cant stat", urlbuf); close(fd); return; } } if (!S_ISREG(statres.st_mode)) { write(con_sock, rep_err_acc, strlen(rep_err_acc)); log_http("not regular file", urlbuf); close(fd); return; } if(!nouidcheck) { if (statres.st_uid != uid || !S_ISREG(statres.st_mode) || !(statres.st_mode & S_IROTH)) { write(con_sock, rep_err_acc, strlen(rep_err_acc)); log_http("bad uid", urlbuf); close(fd); return; } } while (lg = read(fd, buff, 1024)) { write(con_sock, buff, lg); } close(fd); log_http("GET", urlbuf); } void do_main_loop(void) { char request[1024]; int lg; do { if(debug) log_http("INFO", "Waiting for connection"); waitconnection(); if(fork() == 0) { /* I am the child */ close(http_sock); lg = read(con_sock, request, 1024); serve_req(request); close(con_sock); exit(0); } else { /* I am the parent */ close(con_sock); } } while(1); } main(int argc, char **argv) { uid = getuid(); argc--; argv++; while (argc > 0) { if (argv[0][0] != '-') usage(); switch (argv[0][1]) { case 'D': debug++; argv += 1; argc -= 1; break; case 's': nouidcheck=1; security=0; argv += 1; argc -= 1; break; case 'l': log_httpfile = argv[1]; argv += 2; argc -= 2; break; case 'p': http_port = atoi(argv[1]); argv += 2; argc -= 2; break; case 'u': uid = atoi(argv[1]); argv += 2; argc -= 2; break; case 'd': homedir = argv[1]; argv += 2; argc -= 2; break; case 'U': nouidcheck++; argv += 1; argc -= 1; break; default: usage(); } } if (homedir == NULL) homedir = getenv("HOME"); if (chdir(homedir) < 0) { perror("chdir"); exit(-1); } log_http("INFO","Starting..."); init_servconnection(); if(debug) log_http("INFO","Bound socket"); fprintf(stderr, "HTTP daemon started on port %d.\n", http_port); if(!debug) { if(fork()) exit(0); setsid(); } do_main_loop(); }