diff options
Diffstat (limited to 'server.c')
| -rw-r--r-- | server.c | 581 |
1 files changed, 0 insertions, 581 deletions
diff --git a/server.c b/server.c deleted file mode 100644 index a6613d6..0000000 --- a/server.c +++ /dev/null @@ -1,581 +0,0 @@ -#include <errno.h> -#include <fcntl.h> -#include <netinet/in.h> -#include <poll.h> -#include <signal.h> -#include <stdarg.h> -#include <string.h> -#include <sys/socket.h> -#include <sys/stat.h> -#include <unistd.h> - -/* Assertion macro */ -#ifndef Assert -#ifdef DEBUG -#define Assert(expr) if (!(expr)) { \ - raise(SIGTRAP); \ -} -#else -#define Assert(expr) if (!(expr)) { \ - raise(SIGTRAP); \ -} -#endif // DEBUG -#endif // Assert - -/* Dependencies */ -#define CHATTY_IMPL -#include "chatty.h" -#undef CHATTY_IMPL - -#define ARENA_IMPL -#include "arena.h" -#undef ARENA_IMPL -#include "protocol.h" - -/* Configuration options */ -// timeout on polling -#define TIMEOUT 60 * 1000 -// max pending connections -#define MAX_CONNECTIONS 1600 -// Get number of connections from arena position -// NOTE: this is somewhat wrong, because of when disconnections happen -#define FDS_SIZE (fdsArena.pos / sizeof(struct pollfd)) -#define CLIENTS_SIZE (clientsArena.pos / sizeof(Client)) - -// Where to save clients -#define CLIENTS_FILE "_clients" -// Where to write logs -#define LOGFILE "server.log" -// Log to LOGFILE instead of stderr -// #define LOGGING - -// enum for indexing the fds array -enum { FDS_STDIN = 0, - FDS_SERVER, - FDS_CLIENTS }; - -// Client information -typedef struct { - u8 author[AUTHOR_LEN]; // matches author property on other message types - ID id; - struct pollfd* bifd; // Index in fds array - struct pollfd* unifd; // Index in fds array -} Client; -#define CLIENT_FMT "[%s](%lu)" -#define CLIENT_ARG(client) client.author, client.id - -typedef enum { - BIFD = 0, - UNIFD, -} ClientFD; - -// TODO: remove global variable -// For handing out new ids to connections. -// Start at 1 because this makes 0 an invalid client id. -global_variable u32 nclients = 1; - -// Returns client matching id in clients nclients number of clients. -// Returns 0 if no client was found or if id was 0. -Client* -getClientByID(Client* clients, u32 nclients, ID id) -{ - if (!id) return 0; - - for (u32 i = 0; i < nclients; i++) - { - if (clients[i].id == id) - return clients + i; - } - return 0; -} - -// Returns client matching fd in clients nclients number of clients. -// Returns 0 if no clients was found or if fd was -1. -Client* -getClientByFD(Client* clients, u32 nclients, s32 fd) -{ - if (fd == -1) return 0; - - for (u32 i = 0; i < nclients; i++) - { - if ((clients[i].unifd && clients[i].unifd->fd == fd) || - (clients[i].bifd && clients[i].bifd->fd == fd)) - return clients + i; - } - return 0; -} - -// Print TextMessage prettily -void -printTextMessage(TextMessage* message, Client* client, u8 wide) -{ - u8 timestamp[TIMESTAMP_LEN] = {0}; - formatTimestamp(timestamp, message->timestamp); - - if (wide) - { - setlocale(LC_ALL, ""); - wprintf(L"TextMessage: %s [%s] %ls\n", timestamp, client->author, (wchar_t*)&message->text); - } else { - u8 str[message->len]; - wcstombs((char*)str, (wchar_t*)&message->text, message->len * sizeof(*message->text)); - LoggingF("TextMessage: %s [%s] (%d)%s\n", timestamp, client->author, message->len, str); - } -} - -// Send header and anyMessage to each connection in fds that is nfds number of connections except -// for connfd. -// Does not send if pollfd is not set or pollfd->fd is -1. -// Type will filter out only connections matching the type. -void -sendToOthers(Client* clients, u32 nclients, Client* client, ClientFD type, HeaderMessage* header, void* anyMessage) -{ - s32 nsend, fd; - for (u32 i = 0; i < nclients - 1; i ++) - { - if (clients + i == client) continue; - - if (type == UNIFD) - { - if (clients[i].unifd && clients[i].unifd->fd != -1) - fd = clients[i].unifd->fd; - else - continue; - } - else if (type == BIFD) - { - if (clients[i].bifd && clients[i].bifd->fd != -1) - fd = clients[i].bifd->fd; - else - continue; - } - nsend = sendAnyMessage(fd, *header, anyMessage); - - assert(nsend != -1); - LoggingF("sendToOthers "CLIENT_FMT"|%d<-%s %d bytes\n", CLIENT_ARG((clients[i])), fd, headerTypeString(header->type), nsend); - } -} - -// Send header and anyMessage to each connection in fds that is nfds number of connections. -// Does not send if pollfd is not set or pollfd->fd is -1. -// Type will filter out only connections matching the type. -void -sendToAll(Client* clients, u32 nclients, ClientFD type, HeaderMessage* header, void* anyMessage) -{ - s32 nsend; - for (u32 i = 0; i < nclients - 1; i++) - { - if (type == UNIFD) - { - if (clients[i].unifd && clients[i].unifd->fd != -1) - nsend = sendAnyMessage(clients[i].unifd->fd, *header, anyMessage); - else - continue; - } - else if (type == BIFD) - { - if (clients[i].bifd && clients[i].bifd->fd != -1) - nsend = sendAnyMessage(clients[i].bifd->fd, *header, anyMessage); - else - continue; - } - else - assert(0); - assert(nsend != -1); - LoggingF("sendToAll|[%s]->"CLIENT_FMT" %d bytes\n", headerTypeString(header->type), - CLIENT_ARG(clients[i]), - nsend); - } -} - -// Disconnect a client by closing the matching file descriptors -void -disconnect(Client* client) -{ - LoggingF("Disconnecting "CLIENT_FMT"\n", CLIENT_ARG((*client))); - if (client->unifd && client->unifd->fd != -1) - { - close(client->unifd->fd); - client->unifd->fd = -1; - client->unifd = 0; - } - if (client->bifd && client->bifd->fd != -1) - { - close(client->bifd->fd); - client->bifd->fd = -1; - client->bifd = 0; - } -} - -// Disconnects fds+conn from fds with nfds connections, then send a PresenceMessage to other -// clients about disconnection. -void -disconnectAndNotify(Client* clients, u32 nclients, Client* client) -{ - disconnect(client); - - local_persist HeaderMessage header = HEADER_INIT(HEADER_TYPE_PRESENCE); - header.id = client->id; - PresenceMessage message = {.type = PRESENCE_TYPE_DISCONNECTED}; - sendToAll(clients, nclients, UNIFD, &header, &message); -} - -// Receive authentication from pollfd->fd and create client out of it. Look in -// clientsArena if it already exists. Otherwise push a new onto the arena and write its information -// to clients_file. -// See "Authentication" in chatty.h -// Assumes that the client will send a IDMessage or IntroductionMessage -// Returns authenticated client -Client* -authenticate(Arena* clientsArena, s32 clients_file, struct pollfd* pollfd, HeaderMessage header) -{ - s32 nrecv = 0; - Client* client = 0; - - LoggingF("authenticate (%d)|" HEADER_FMT "\n", pollfd->fd, HEADER_ARG(header)); - - /* Scenario 1: Search for existing client */ - if (header.type == HEADER_TYPE_ID) - { - IDMessage message; - s32 nrecv = recv(pollfd->fd, &message, sizeof(message), 0); - assert(nrecv == sizeof(message)); - - client = getClientByID((Client*)clientsArena->addr, nclients, message.id); - if (!client) - { - LoggingF("authenticate (%d)|notfound\n", pollfd->fd); - header.type = HEADER_TYPE_ERROR; - ErrorMessage error_message = ERROR_INIT(ERROR_TYPE_NOTFOUND); - sendAnyMessage(pollfd->fd, header, &error_message); - return 0; - } - else - { - LoggingF("authenticate (%d)|found [%s](%lu)\n", pollfd->fd, client->author, client->id); - header.type = HEADER_TYPE_ERROR; - ErrorMessage error_message = ERROR_INIT(ERROR_TYPE_SUCCESS); - sendAnyMessage(pollfd->fd, header, &error_message); - } - - if (!client->bifd) - client->bifd = pollfd; - else if (!client->unifd) - client->unifd = pollfd; - else - assert(0); - - - return client; - } - /* Scenario 2: Create a new client */ - else if (header.type == HEADER_TYPE_INTRODUCTION) - { - IntroductionMessage message; - nrecv = recv(pollfd->fd, &message, sizeof(message), 0); - if (nrecv != sizeof(message)) - { - LoggingF("authenticate (%d)|err: %d/%lu bytes\n", pollfd->fd, nrecv, sizeof(message)); - return 0; - } - - // Copy metadata from IntroductionMessage - client = ArenaPush(clientsArena, sizeof(*client)); - memcpy(client->author, message.author, AUTHOR_LEN); - client->id = nclients; - - if (!client->bifd) - client->bifd = pollfd; - else if (!client->unifd) - client->unifd = pollfd; - else - assert(0); - - nclients++; - -#ifdef IMPORT_ID - write(clients_file, client, sizeof(*client)); -#endif - LoggingF("authenticate (%d)|Added [%s](%lu)\n", pollfd->fd, client->author, client->id); - - // Send ID to new client - HeaderMessage header = HEADER_INIT(HEADER_TYPE_ID); - IDMessage id_message; - id_message.id = client->id; - - s32 nsend = sendAnyMessage(pollfd->fd, header, &id_message); - assert(nsend != -1); - - return client; - } - - LoggingF("authenticate (%d)|Wrong header expected %s or %s\n", pollfd->fd, - headerTypeString(HEADER_TYPE_INTRODUCTION), - headerTypeString(HEADER_TYPE_ID)); - return 0; -} - -int -main(int argc, char** argv) -{ - signal(SIGPIPE, SIG_IGN); - - LogFD = 2; - // optional logging - if (argc > 1) - { - if (*argv[1] == '-') - if (argv[1][1] == 'l') - { - LogFD = open(LOGFILE, O_RDWR | O_CREAT | O_TRUNC, 0600); - assert(LogFD != -1); - } - } - - s32 serverfd; - // Start listening on the socket - { - s32 err; - u32 on = 1; - serverfd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); - assert(serverfd > 2); - - err = setsockopt(serverfd, SOL_SOCKET, SO_REUSEADDR, (u8*)&on, sizeof(on)); - assert(!err); - - const struct sockaddr_in address = { - AF_INET, - htons(PORT), - {0}, - {0}, - }; - - err = bind(serverfd, (const struct sockaddr*)&address, sizeof(address)); - assert(!err); - - err = listen(serverfd, MAX_CONNECTIONS); - assert(!err); - LoggingF("Listening on :%d\n", PORT); - } - - Arena clientsArena; - Arena fdsArena; - Arena msgsArena; - ArenaAlloc(&clientsArena, MAX_CONNECTIONS * sizeof(Client)); - ArenaAlloc(&fdsArena, MAX_CONNECTIONS * 2 * sizeof(struct pollfd)); - ArenaAlloc(&msgsArena, Megabytes(128)); // storing received messages - struct pollfd* fds = fdsArena.addr; - Client* clients = clientsArena.addr; - - // Initializing fds - struct pollfd* fdsAddr; - struct pollfd newpollfd = {-1, POLLIN, 0}; // for copying with events already set - // initialize fds structure - newpollfd.fd = 0; - fdsAddr = ArenaPush(&fdsArena, sizeof(*fds)); - memcpy(fdsAddr, &newpollfd, sizeof(*fds)); - // add serverfd - newpollfd.fd = serverfd; - fdsAddr = ArenaPush(&fdsArena, sizeof(*fds)); - memcpy(fdsAddr, &newpollfd, sizeof(*fds)); - newpollfd.fd = -1; - - s32 clients_file; -#ifdef IMPORT_ID - clients_file = open(CLIENTS_FILE, O_RDWR | O_CREAT | O_APPEND, 0600); - assert(clients_file != -1); - struct stat statbuf; - assert(fstat(clients_file, &statbuf) != -1); - - read(clients_file, clients, statbuf.st_size); - if (statbuf.st_size > 0) - { - ArenaPush(&clientsArena, statbuf.st_size); - LoggingF("Imported %lu client(s)\n", statbuf.st_size / sizeof(*clients)); - nclients += statbuf.st_size / sizeof(*clients); - - // Reset pointers on imported clients - for (u32 i = 0; i < nclients - 1; i++) - { - clients[i].unifd = 0; - clients[i].bifd = 0; - } - } - for (u32 i = 0; i < nclients - 1; i++) - LoggingF("Imported: " CLIENT_FMT "\n", CLIENT_ARG(clients[i])); -#else - clients_file = 0; -#endif - - // Initialize the rest of the fds array - for (u32 i = FDS_CLIENTS; i < MAX_CONNECTIONS; i++) - fds[i] = newpollfd; - - while (1) - { - s32 err = poll(fds, FDS_SIZE, TIMEOUT); - assert(err != -1); - - if (fds[FDS_STDIN].revents & POLLIN) - { - u8 c; // exit on ctrl-d - if (!read(fds[FDS_STDIN].fd, &c, 1)) - break; - } - else if (fds[FDS_SERVER].revents & POLLIN) - { - // TODO: what if we are not aligned by 2 anymore? - s32 clientfd = accept(serverfd, 0, 0); - - if (clientfd == -1) - { - LoggingF("Error while accepting connection (%d)\n", clientfd); - continue; - } - else - LoggingF("New connection(%d)\n", clientfd); - - // TODO: find empty space in arena (fragmentation) - if (nclients + 1 == MAX_CONNECTIONS) - { - local_persist HeaderMessage header = HEADER_INIT(HEADER_TYPE_ERROR); - local_persist ErrorMessage message = ERROR_INIT(ERROR_TYPE_TOOMANYCONNECTIONS); - sendAnyMessage(clientfd, header, &message); - if (clientfd != -1) - close(clientfd); - LoggingF("Max clients reached. Rejected connection\n"); - } - else - { - // no more space, allocate - struct pollfd* pollfd = ArenaPush(&fdsArena, sizeof(*pollfd)); - pollfd->fd = clientfd; - LoggingF("Added pollfd(%d)\n", clientfd); - } - } - - for (u32 conn = FDS_CLIENTS; conn < FDS_SIZE; conn++) - { - if (!(fds[conn].revents & POLLIN)) continue; - if (fds[conn].fd == -1) continue; - LoggingF("Message(%d)\n", fds[conn].fd); - - // We received a message, try to parse the header - HeaderMessage header; - s32 nrecv = recv(fds[conn].fd, &header, sizeof(header), 0); - if(nrecv == -1) - { - LoggingF("Received error from fd: %d, errno: %d\n", fds[conn].fd, errno); - }; - - Client* client; - if (nrecv != sizeof(header)) - { - client = getClientByFD(clients, nclients, fds[conn].fd); - if (client) - { - LoggingF("Received %d/%lu bytes "CLIENT_FMT"\n", nrecv, sizeof(header), CLIENT_ARG((*client))); - disconnectAndNotify(clients, nclients, client); - } - else - { - LoggingF("Got error/disconnect from unauthenticated client\n"); - close(fds[conn].fd); - fds[conn].fd = -1; - } - continue; - } - LoggingF("Received(%d): " HEADER_FMT "\n", fds[conn].fd, HEADER_ARG(header)); - - // Authentication - if (!header.id) - { - LoggingF("No client for connection(%d)\n", fds[conn].fd); - - client = authenticate(&clientsArena, clients_file, fds + conn, header); - - if (!client) - { - LoggingF("Could not initialize client (%d)\n", fds[conn].fd); - close(fds[conn].fd); - fds[conn].fd = -1; - } - /* This is the first time a message is sent, because unifd is not yet set. */ - else if (!client->unifd) - { - LoggingF("Send connected message\n"); - local_persist HeaderMessage header = HEADER_INIT(HEADER_TYPE_PRESENCE); - header.id = client->id; - PresenceMessage message = {.type = PRESENCE_TYPE_CONNECTED}; - sendToOthers(clients, nclients, client, UNIFD, &header, &message); - } - continue; - } - - client = getClientByID(clients, nclients, header.id); - if (!client) - { - LoggingF("No client for id %d\n", fds[conn].fd); - - header.type = HEADER_TYPE_ERROR; - ErrorMessage message = ERROR_INIT(ERROR_TYPE_NOTFOUND); - - sendAnyMessage(fds[conn].fd, header, &message); - - // Reject connection - fds[conn].fd = -1; - close(fds[conn].fd); - continue; - } - - switch (header.type) { - /* Send text message to all other clients */ - case HEADER_TYPE_TEXT: - { - TextMessage* text_message = recvTextMessage(&msgsArena, fds[conn].fd); - LoggingF("Received(%d): ", fds[conn].fd); - printTextMessage(text_message, client, 0); - - sendToOthers(clients, nclients, client, UNIFD, &header, text_message); - } break; - /* Send back client information */ - case HEADER_TYPE_ID: - { - IDMessage id_message; - s32 nrecv = recv(fds[conn].fd, &id_message, sizeof(id_message), 0); - assert(nrecv == sizeof(id_message)); - - client = getClientByID(clients, nclients, id_message.id); - if (!client) - { - header.type = HEADER_TYPE_ERROR; - ErrorMessage message = ERROR_INIT(ERROR_TYPE_NOTFOUND); - s32 nsend = sendAnyMessage(fds[conn].fd, header, &message); - assert(nsend != -1); - break; - } - - HeaderMessage header = HEADER_INIT(HEADER_TYPE_INTRODUCTION); - IntroductionMessage introduction_message; - header.id = client->id; - memcpy(introduction_message.author, client->author, AUTHOR_LEN); - - nrecv = sendAnyMessage(fds[conn].fd, header, &introduction_message); - assert(nrecv != -1); - } break; - default: - LoggingF("Unhandled '%s' from "CLIENT_FMT"(%d)\n", headerTypeString(header.type), - CLIENT_ARG((*client)), - fds[conn].fd); - disconnectAndNotify(client, nclients, client); - continue; - } - } - } - -#ifdef IMPORT_ID - close(clients_file); -#endif - - return 0; -} |