| 1 | /*************************************************************************** |
| 2 | * Copyright (C) 2006 by Gerd v. Egidy * |
| 3 | * gve@intra2net.com * |
| 4 | * * |
| 5 | * This library is free software; you can redistribute it and/or modify * |
| 6 | * it under the terms of the GNU Lesser General Public License version * |
| 7 | * 2.1 as published by the Free Software Foundation. * |
| 8 | * * |
| 9 | * This library is distributed in the hope that it will be useful, * |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of * |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * |
| 12 | * GNU Lesser General Public License for more details. * |
| 13 | * * |
| 14 | * You should have received a copy of the GNU Lesser General Public * |
| 15 | * License along with this program; if not, write to the * |
| 16 | * Free Software Foundation, Inc., * |
| 17 | * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * |
| 18 | ***************************************************************************/ |
| 19 | |
| 20 | #include <stdio.h> |
| 21 | #include <errno.h> |
| 22 | #include <stdlib.h> |
| 23 | #include <unistd.h> |
| 24 | #include <sys/types.h> |
| 25 | #include <sys/socket.h> |
| 26 | #include <sys/un.h> |
| 27 | #include <sys/time.h> |
| 28 | #include <arpa/inet.h> |
| 29 | #include <netinet/in.h> |
| 30 | #include <netdb.h> |
| 31 | #include <fcntl.h> |
| 32 | #include <time.h> |
| 33 | #include <pwd.h> |
| 34 | #include <grp.h> |
| 35 | |
| 36 | #include <sstream> |
| 37 | |
| 38 | #include "socket_server.hxx" |
| 39 | #include "t2n_exception.hxx" |
| 40 | #include "log.hxx" |
| 41 | |
| 42 | using namespace std; |
| 43 | |
| 44 | namespace libt2n |
| 45 | { |
| 46 | |
| 47 | /** @brief create a new tcp-based server |
| 48 | @param port tcp port you want to listen on |
| 49 | @param ip the local ip you want to listen on. "0.0.0.0" means all local ips (default). |
| 50 | */ |
| 51 | socket_server::socket_server(int port, const std::string& ip) |
| 52 | : server(), socket_handler(0,tcp_s) |
| 53 | { |
| 54 | /* Create the socket. */ |
| 55 | sock = socket (PF_INET, SOCK_STREAM, 0); |
| 56 | if (sock < 0) |
| 57 | EXCEPTIONSTREAM(error,t2n_server_error,"error opening socket: " << strerror(errno)); |
| 58 | |
| 59 | set_socket_options(sock); |
| 60 | |
| 61 | /* Give the socket a name. */ |
| 62 | struct sockaddr_in sockaddr; |
| 63 | sockaddr.sin_family = AF_INET; |
| 64 | sockaddr.sin_port = htons(port); |
| 65 | |
| 66 | if (inet_aton(ip.c_str(),&sockaddr.sin_addr) == 0) |
| 67 | EXCEPTIONSTREAM(error,t2n_server_error,"failed listening on invalid ip " << ip); |
| 68 | |
| 69 | if (bind (sock, (struct sockaddr *) &sockaddr, sizeof (sockaddr)) < 0) |
| 70 | EXCEPTIONSTREAM(error,t2n_server_error,"error binding socket: " << strerror(errno)); |
| 71 | |
| 72 | start_listening(); |
| 73 | } |
| 74 | |
| 75 | /** @brief create a new unix-socked-based server |
| 76 | @param path path of the socket |
| 77 | @param filemode permissions you want to open the socket with |
| 78 | @param user local username for the socket |
| 79 | @param group local groupname for the socket |
| 80 | */ |
| 81 | socket_server::socket_server(const std::string& path, mode_t filemode, const std::string& user, const std::string& group) |
| 82 | : server(), socket_handler(0,unix_s) |
| 83 | { |
| 84 | unix_path=path; |
| 85 | |
| 86 | /* Create the socket. */ |
| 87 | sock = socket (PF_UNIX, SOCK_STREAM, 0); |
| 88 | if (sock < 0) |
| 89 | EXCEPTIONSTREAM(error,t2n_server_error,"error opening socket: " << strerror(errno)); |
| 90 | |
| 91 | set_socket_options(sock); |
| 92 | |
| 93 | /* Give the socket a name. */ |
| 94 | struct sockaddr_un unix_name; |
| 95 | unix_name.sun_family = AF_UNIX; |
| 96 | strncpy (unix_name.sun_path, unix_path.c_str(),sizeof(unix_name.sun_path)); |
| 97 | |
| 98 | /* just to make sure there is no other socket file */ |
| 99 | unlink (unix_name.sun_path); |
| 100 | |
| 101 | if (bind (sock, (struct sockaddr *) &unix_name, sizeof (unix_name)) < 0) |
| 102 | EXCEPTIONSTREAM(error,t2n_server_error,"error binding socket: " << strerror(errno)); |
| 103 | |
| 104 | /* change permissions */ |
| 105 | if (chmod (unix_name.sun_path, filemode) != 0) |
| 106 | EXCEPTIONSTREAM(error,t2n_server_error,"error changing permission: " << strerror(errno)); |
| 107 | |
| 108 | if (!user.empty() && !group.empty()) |
| 109 | { |
| 110 | // TODO maybe use current user/group if one of them is empty |
| 111 | |
| 112 | struct passwd *socket_user = getpwnam (user.c_str()); |
| 113 | if (socket_user == NULL) |
| 114 | EXCEPTIONSTREAM(error,t2n_server_error,"error getting socket user: " << strerror(errno)); |
| 115 | |
| 116 | struct group *socket_group = getgrnam (group.c_str()); |
| 117 | if (socket_group == NULL) |
| 118 | EXCEPTIONSTREAM(error,t2n_server_error,"error getting socket group: " << strerror(errno)); |
| 119 | |
| 120 | if (chown (unix_name.sun_path, socket_user->pw_uid, socket_group->gr_gid) != 0) |
| 121 | EXCEPTIONSTREAM(error,t2n_server_error,"error changing socket ownership: " << strerror(errno)); |
| 122 | } |
| 123 | |
| 124 | start_listening(); |
| 125 | } |
| 126 | |
| 127 | socket_server::~socket_server() |
| 128 | { |
| 129 | socket_handler::close(); |
| 130 | |
| 131 | if (get_type()==unix_s) |
| 132 | unlink(unix_path.c_str()); |
| 133 | } |
| 134 | |
| 135 | /// start listening on a new server socket (called by the constructors) |
| 136 | void socket_server::start_listening() |
| 137 | { |
| 138 | if (listen (sock, 5) < 0) |
| 139 | EXCEPTIONSTREAM(error,t2n_server_error,"error listening to socket: " << strerror(errno)); |
| 140 | |
| 141 | /* clear & insert server sock into the fd_tab to prepare select */ |
| 142 | FD_ZERO(&connection_set); |
| 143 | FD_SET (sock, &connection_set); |
| 144 | } |
| 145 | |
| 146 | /// handle a new connection from a client |
| 147 | void socket_server::new_connection() |
| 148 | { |
| 149 | struct sockaddr_un clientname; |
| 150 | |
| 151 | unsigned int size = sizeof (clientname); |
| 152 | int newsock = accept (sock,(struct sockaddr *) &clientname,&size); |
| 153 | if (newsock < 0) |
| 154 | { |
| 155 | // return on non-fatal errors (list taken from man-page) |
| 156 | if (errno == EAGAIN || errno == EWOULDBLOCK || errno == ECONNABORTED || errno == EINTR || |
| 157 | errno == EMFILE || errno == ENFILE || errno == ENOBUFS || errno == ENOMEM || |
| 158 | errno == EPROTO || errno == EPERM || errno == ETIMEDOUT) |
| 159 | { |
| 160 | LOGSTREAM(error,"non-fatal accept error: " << strerror(errno)); |
| 161 | return; |
| 162 | } |
| 163 | |
| 164 | /* fatal error: will usually kill or restart the server */ |
| 165 | EXCEPTIONSTREAM(error,t2n_server_error,"fatal error accepting connection: " << strerror(errno)); |
| 166 | } |
| 167 | |
| 168 | FD_SET (newsock, &connection_set); |
| 169 | |
| 170 | socket_server_connection *nc=new socket_server_connection(newsock, get_type(), get_default_timeout()); |
| 171 | nc->set_socket_options(newsock); |
| 172 | |
| 173 | add_connection(nc); |
| 174 | |
| 175 | return; |
| 176 | } |
| 177 | |
| 178 | /** @brief look for new connections and new data in any of the existing connections |
| 179 | @param usec_timeout wait until new data is found, max timeout usecs. |
| 180 | -1: wait endless |
| 181 | 0: return instantly |
| 182 | @param usec_timeout_remaining if non-NULL the function will write the |
| 183 | not used time to the given target |
| 184 | @retval true if new data was found (does not mean that the received data |
| 185 | is a complete packet though) |
| 186 | */ |
| 187 | bool socket_server::fill_buffer(long long usec_timeout,long long* usec_timeout_remaining) |
| 188 | { |
| 189 | fd_set used_fdset=connection_set; |
| 190 | |
| 191 | /* set timeout */ |
| 192 | struct timeval tval; |
| 193 | struct timeval *timeout_ptr; |
| 194 | |
| 195 | if (usec_timeout == -1) |
| 196 | timeout_ptr = NULL; |
| 197 | else |
| 198 | { |
| 199 | timeout_ptr = &tval; |
| 200 | |
| 201 | // timeout von long long usec in int sec + int usec umrechnen |
| 202 | tval.tv_sec = usec_timeout / 1000000; |
| 203 | tval.tv_usec = usec_timeout % 1000000; |
| 204 | } |
| 205 | |
| 206 | int ret=select (FD_SETSIZE, &used_fdset, NULL, NULL, timeout_ptr); |
| 207 | |
| 208 | // return the timeout we did not use |
| 209 | if (usec_timeout > 0 && usec_timeout_remaining != NULL) |
| 210 | *usec_timeout_remaining=(tval.tv_sec*1000000)+tval.tv_usec; |
| 211 | |
| 212 | if (ret < 0) |
| 213 | { |
| 214 | if (errno == EINTR) |
| 215 | { |
| 216 | // select interrupted by signal |
| 217 | ret=0; |
| 218 | } |
| 219 | else |
| 220 | EXCEPTIONSTREAM(error,t2n_server_error,"select error: " << strerror(errno)); |
| 221 | } |
| 222 | |
| 223 | if (ret > 0) |
| 224 | { |
| 225 | // we have data pending |
| 226 | |
| 227 | // check for new connection |
| 228 | if (FD_ISSET (sock, &used_fdset)) |
| 229 | { |
| 230 | new_connection(); |
| 231 | } |
| 232 | |
| 233 | // check all connections for pending data |
| 234 | return fill_connection_buffers(); |
| 235 | } |
| 236 | |
| 237 | return false; |
| 238 | } |
| 239 | |
| 240 | /// call fill_buffer() on all connections, called from fill_buffer() |
| 241 | bool socket_server::fill_connection_buffers() |
| 242 | { |
| 243 | bool data_found; |
| 244 | |
| 245 | std::map<unsigned int, server_connection*>::iterator ie=connections.end(); |
| 246 | for(std::map<unsigned int, server_connection*>::iterator i=connections.begin(); i != ie; i++) |
| 247 | if (!i->second->server_connection::is_closed()) |
| 248 | { |
| 249 | // shutdown all connections which throw exceptions to protect the server |
| 250 | try |
| 251 | { |
| 252 | if (i->second->fill_buffer(0)) |
| 253 | data_found=true; |
| 254 | } |
| 255 | catch (t2n_transfer_error &e) |
| 256 | { i->second->close(); } |
| 257 | catch(...) |
| 258 | { throw; } |
| 259 | } |
| 260 | |
| 261 | return data_found; |
| 262 | } |
| 263 | |
| 264 | /// remove the socket of a connection after the connection has been closed |
| 265 | void socket_server::remove_connection_socket(int sock) |
| 266 | { |
| 267 | FD_CLR(sock, &connection_set); |
| 268 | } |
| 269 | |
| 270 | /// close this connection. complete data waiting in the buffer can still be retrieved. |
| 271 | void socket_server_connection::close() |
| 272 | { |
| 273 | if (!server_connection::is_closed()) |
| 274 | { |
| 275 | socket_handler::close(); |
| 276 | server_connection::close(); |
| 277 | } |
| 278 | |
| 279 | if (my_server) |
| 280 | { |
| 281 | dynamic_cast<socket_server*>(my_server)->remove_connection_socket(sock); |
| 282 | } |
| 283 | } |
| 284 | |
| 285 | } |