/**************************************************************************** * netutils/thttpd/thttpd.c * Tiny HTTP Server * * Copyright (C) 2009, 2011 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Derived from the file of the same name in the original THTTPD package: * * Copyright © 1995,1998,1999,2000,2001 by Jef Poskanzer . * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "config.h" #include "fdwatch.h" #include "libhttpd.h" #include "thttpd_alloc.h" #include "thttpd_strings.h" #include "timers.h" #ifdef CONFIG_THTTPD /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ #ifndef MAXPATHLEN # define MAXPATHLEN 64 #endif /* The connection states */ #define CNST_FREE 0 #define CNST_READING 1 #define CNST_SENDING 2 #define CNST_LINGERING 3 #define SPARE_FDS 2 #define AVAILABLE_FDS (CONFIG_NSOCKET_DESCRIPTORS - SPARE_FDS) /**************************************************************************** * Private Types ****************************************************************************/ struct connect_s { struct connect_s *next; int conn_state; httpd_conn *hc; time_t active_at; Timer *wakeup_timer; Timer *linger_timer; off_t end_offset; /* The final offset+1 of the file to send */ off_t offset; /* The current offset into the file to send */ bool eof; /* Set true when length==0 read from file */ }; /**************************************************************************** * Private Data ****************************************************************************/ static httpd_server *hs; static struct connect_s *free_connections; static struct connect_s *connects; static struct fdwatch_s *fw; /**************************************************************************** * Public Data ****************************************************************************/ /**************************************************************************** * Private Function Prototypes ****************************************************************************/ static void shut_down(void); static int handle_newconnect(struct timeval *tv, int listen_fd); static void handle_read(struct connect_s *conn, struct timeval *tv); static void handle_send(struct connect_s *conn, struct timeval *tv); static void handle_linger(struct connect_s *conn, struct timeval *tv); static void finish_connection(struct connect_s *conn, struct timeval *tv); static void clear_connection(struct connect_s *conn, struct timeval *tv); static void really_clear_connection(struct connect_s *conn); static void idle(ClientData client_data, struct timeval *nowP); static void linger_clear_connection(ClientData client_data, struct timeval *nowP); static void occasional(ClientData client_data, struct timeval *nowP); /**************************************************************************** * Private Functions ****************************************************************************/ static void shut_down(void) { int cnum; for (cnum = 0; cnum < AVAILABLE_FDS; ++cnum) { if (connects[cnum].conn_state != CNST_FREE) { httpd_close_conn(connects[cnum].hc); } if (connects[cnum].hc != NULL) { httpd_destroy_conn(connects[cnum].hc); httpd_free((void *)connects[cnum].hc); connects[cnum].hc = NULL; } } if (hs) { httpd_server *ths = hs; hs = NULL; if (ths->listen_fd != -1) { fdwatch_del_fd(fw, ths->listen_fd); } httpd_terminate(ths); } tmr_destroy(); httpd_free((void *)connects); } static int handle_newconnect(struct timeval *tv, int listen_fd) { struct connect_s *conn; ClientData client_data; /* This loops until the accept() fails, trying to start new connections as * fast as possible so we don't overrun the listen queue. */ nvdbg("New connection(s) on listen_fd %d\n", listen_fd); for (;;) { /* Get the next free connection from the free list */ conn = free_connections; /* Are there any free connections? */ if (!conn) { /* Out of connection slots. Run the timers, then the existing * connections, and maybe we'll free up a slot by the time we get * back here. */ ndbg("No free connections\n"); tmr_run(tv); return -1; } /* Make the httpd_conn if necessary */ if (!conn->hc) { conn->hc = NEW(httpd_conn, 1); if (conn->hc == NULL) { ndbg("out of memory allocating an httpd_conn\n"); exit(1); } conn->hc->initialized = 0; } /* Get the connection */ switch (httpd_get_conn(hs, listen_fd, conn->hc)) { /* Some error happened. Run the timers, then the existing * connections. Maybe the error will clear. */ case GC_FAIL: tmr_run(tv); return -1; /* No more connections to accept for now */ case GC_NO_MORE: return 0; default: break; } nvdbg("New connection fd %d\n", conn->hc->conn_fd); /* Remove the connection entry from the free list */ conn->conn_state = CNST_READING; free_connections = conn->next; conn->next = NULL; client_data.p = conn; conn->active_at = tv->tv_sec; conn->wakeup_timer = NULL; conn->linger_timer = NULL; conn->offset = 0; /* Set the connection file descriptor to no-delay mode */ httpd_set_ndelay(conn->hc->conn_fd); fdwatch_add_fd(fw, conn->hc->conn_fd, conn); } } static void handle_read(struct connect_s *conn, struct timeval *tv) { ClientData client_data; httpd_conn *hc = conn->hc; off_t actual; int sz; /* Is there room in our buffer to read more bytes? */ if (hc->read_idx >= hc->read_size) { if (hc->read_size > CONFIG_THTTPD_MAXREALLOC) { BADREQUEST("MAXREALLOC"); goto errout_with_400; } httpd_realloc_str(&hc->read_buf, &hc->read_size, hc->read_size + CONFIG_THTTPD_REALLOCINCR); } /* Read some more bytes */ sz = read(hc->conn_fd, &(hc->read_buf[hc->read_idx]), hc->read_size - hc->read_idx); if (sz == 0) { BADREQUEST("EOF"); goto errout_with_400; } if (sz < 0) { /* Ignore EINTR and EAGAIN. Also ignore EWOULDBLOCK. At first glance * you would think that connections returned by fdwatch as readable * should never give an EWOULDBLOCK; however, this apparently can * happen if a packet gets garbled. */ if (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK) { return; } ndbg("read(fd=%d) failed: %d\n", hc->conn_fd, errno); BADREQUEST("read"); goto errout_with_400; } hc->read_idx += sz; conn->active_at = tv->tv_sec; /* Do we have a complete request yet? */ switch (httpd_got_request(hc)) { case GR_NO_REQUEST: return; case GR_BAD_REQUEST: BADREQUEST("httpd_got_request"); goto errout_with_400; } /* Yes. Try parsing and resolving it */ if (httpd_parse_request(hc) < 0) { goto errout_with_connection; } /* Start the connection going */ if (httpd_start_request(hc, tv) < 0) { /* Something went wrong. Close down the connection */ goto errout_with_connection; } /* Set up the file offsets to read */ conn->eof = false; if (hc->got_range) { conn->offset = hc->range_start; conn->end_offset = hc->range_end + 1; } else { conn->offset = 0; if (hc->bytes_to_send < 0) { conn->end_offset = 0; } else { conn->end_offset = hc->bytes_to_send; } } /* Check if it's already handled */ if (hc->file_fd < 0) { /* No file descriptor means someone else is handling it */ conn->offset = hc->bytes_sent; goto errout_with_connection; } if (conn->offset >= conn->end_offset) { /* There's nothing to send */ goto errout_with_connection; } /* Seek to the offset of the next byte to send */ actual = lseek(hc->file_fd, conn->offset, SEEK_SET); if (actual != conn->offset) { ndbg("fseek to %d failed: offset=%d errno=%d\n", conn->offset, actual, errno); BADREQUEST("lseek"); goto errout_with_400; } /* We have a valid connection and a file to send to it */ conn->conn_state = CNST_SENDING; client_data.p = conn; fdwatch_del_fd(fw, hc->conn_fd); return; errout_with_400: BADREQUEST("errout"); httpd_send_err(hc, 400, httpd_err400title, "", httpd_err400form, ""); errout_with_connection: finish_connection(conn, tv); return; } static inline int read_buffer(struct connect_s *conn) { httpd_conn *hc = conn->hc; ssize_t nread = 0; if (hc->buflen < CONFIG_THTTPD_IOBUFFERSIZE && !conn->eof) { nread = read(hc->file_fd, &hc->buffer[hc->buflen], CONFIG_THTTPD_IOBUFFERSIZE - hc->buflen); if (nread == 0) { /* Reading zero bytes means we are at the end of file */ conn->end_offset = conn->offset; conn->eof = true; } else if (nread > 0) { hc->buflen += nread; } } return nread; } static void handle_send(struct connect_s *conn, struct timeval *tv) { httpd_conn *hc = conn->hc; int nwritten; int nread; /* Read until the entire file is sent -- this could take awhile!! */ while (conn->offset < conn->end_offset) { nvdbg("offset: %d end_offset: %d bytes_sent: %d\n", conn->offset, conn->end_offset, conn->hc->bytes_sent); /* Fill the rest of the response buffer with file data */ nread = read_buffer(conn); if (nread < 0) { ndbg("File read error: %d\n", errno); goto errout_clear_connection; } nvdbg("Read %d bytes, buflen %d\n", nread, hc->buflen); /* Send the buffer */ if (hc->buflen > 0) { /* httpd_write does not return until all bytes have been sent * (or an error occurs). */ nwritten = httpd_write(hc->conn_fd, hc->buffer, hc->buflen); if (nwritten < 0) { ndbg("Error sending %s: %d\n", hc->encodedurl, errno); goto errout_clear_connection; } /* We wrote one full buffer of data (httpd_write does not * return until the full buffer is written (or an error occurs). */ conn->active_at = tv->tv_sec; hc->buflen = 0; /* And update how much of the file we wrote */ conn->offset += nwritten; conn->hc->bytes_sent += nwritten; nvdbg("Wrote %d bytes\n", nwritten); } } /* The file transfer is complete -- finish the connection */ nvdbg("Finish connection\n"); finish_connection(conn, tv); return; errout_clear_connection: ndbg("Clear connection\n"); clear_connection(conn, tv); return; } static void handle_linger(struct connect_s *conn, struct timeval *tv) { httpd_conn *hc = conn->hc; int ret; /* In lingering-close mode we just read and ignore bytes. An error or EOF * ends things, otherwise we go until a timeout */ ret = read(conn->hc->conn_fd, hc->buffer, CONFIG_THTTPD_IOBUFFERSIZE); if (ret < 0 && (errno == EINTR || errno == EAGAIN)) { return; } if (ret <= 0) { really_clear_connection(conn); } } static void finish_connection(struct connect_s *conn, struct timeval *tv) { /* If we haven't actually sent the buffered response yet, do so now */ httpd_write_response(conn->hc); /* And clear */ clear_connection(conn, tv); } static void clear_connection(struct connect_s *conn, struct timeval *tv) { ClientData client_data; if (conn->wakeup_timer != NULL) { tmr_cancel(conn->wakeup_timer); conn->wakeup_timer = 0; } /* This is our version of Apache's lingering_close() routine, which is * their version of the often-broken SO_LINGER socket option. For why * this is necessary, see http://www.apache.org/docs/misc/fin_wait_2.html * What we do is delay the actual closing for a few seconds, while reading * any bytes that come over the connection. However, we don't want to do * this unless it's necessary, because it ties up a connection slot and * file descriptor which means our maximum connection-handling rateis * lower. So, elsewhere we set a flag when we detect the few * circumstances that make a lingering close necessary. If the flag isn't * set we do the real close now. */ if (conn->conn_state == CNST_LINGERING) { /* If we were already lingering, shut down for real */ tmr_cancel(conn->linger_timer); conn->linger_timer = NULL; conn->hc->should_linger = false; } else if (conn->hc->should_linger) { fdwatch_del_fd(fw, conn->hc->conn_fd); conn->conn_state = CNST_LINGERING; fdwatch_add_fd(fw, conn->hc->conn_fd, conn); client_data.p = conn; conn->linger_timer = tmr_create(tv, linger_clear_connection, client_data, CONFIG_THTTPD_LINGER_MSEC, 0); if (conn->linger_timer != NULL) { return; } ndbg("tmr_create(linger_clear_connection) failed\n"); } /* Either we are done lingering, we shouldn't linger, or we failed to setup the linger */ really_clear_connection(conn); } static void really_clear_connection(struct connect_s *conn) { fdwatch_del_fd(fw, conn->hc->conn_fd); httpd_close_conn(conn->hc); if (conn->linger_timer != NULL) { tmr_cancel(conn->linger_timer); conn->linger_timer = 0; } /* Put the connection structure back on the free list */ conn->conn_state = CNST_FREE; conn->next = free_connections; free_connections = conn; } static void idle(ClientData client_data, struct timeval *nowP) { int cnum; struct connect_s *conn; for (cnum = 0; cnum < AVAILABLE_FDS; ++cnum) { conn = &connects[cnum]; switch (conn->conn_state) { case CNST_READING: if (nowP->tv_sec - conn->active_at >= CONFIG_THTTPD_IDLE_READ_LIMIT_SEC) { ndbg("%s connection timed out reading\n", httpd_ntoa(&conn->hc->client_addr)); httpd_send_err(conn->hc, 408, httpd_err408title, "", httpd_err408form, ""); finish_connection(conn, nowP); } break; case CNST_SENDING: if (nowP->tv_sec - conn->active_at >= CONFIG_THTTPD_IDLE_SEND_LIMIT_SEC) { ndbg("%s connection timed out sending\n", httpd_ntoa(&conn->hc->client_addr)); clear_connection(conn, nowP); } break; } } } static void linger_clear_connection(ClientData client_data, struct timeval *nowP) { struct connect_s *conn; nvdbg("Clear connection\n"); conn = (struct connect_s *) client_data.p; conn->linger_timer = NULL; really_clear_connection(conn); } static void occasional(ClientData client_data, struct timeval *nowP) { tmr_cleanup(); } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Function: thttpd_main * * Description: * This function is the entrypoint into the THTTPD server. It does not * return. It may be called, the normal mechanism for starting the server * is: * * 1) Set is g_thttpdsymtab and g_thttpdnsymbols. The user is required * to provide a symbol table to use for binding CGI programs (if CGI * is enabled. See examples/nxflat and examples/thttpd for examples of * how such a symbol table may be created. * 2) Call task_create() to start thttpd_main() * ****************************************************************************/ #ifdef CONFIG_BUILD_KERNEL int main(int argc, FAR char *argv[]) #else int thttpd_main(int argc, char **argv) #endif { int num_ready; int cnum; FAR struct connect_s *conn; FAR httpd_conn *hc; httpd_sockaddr sa; struct timeval tv; #ifdef CONFIG_THTTPD_DIR int ret; #endif nvdbg("THTTPD started\n"); /* Setup host address */ #ifdef CONFIG_NET_IPv6 # error "IPv6 support not yet implemented" #else sa.sin_family = AF_INET; sa.sin_port = HTONS(CONFIG_THTTPD_PORT); sa.sin_addr.s_addr = HTONL(CONFIG_THTTPD_IPADDR); #endif /* Initialize the fdwatch package to handle all of the configured * socket descriptors */ fw = fdwatch_initialize(CONFIG_NSOCKET_DESCRIPTORS); if (!fw) { ndbg("fdwatch initialization failure\n"); exit(1); } /* Switch directories again if requested */ #ifdef CONFIG_THTTPD_DATADIR if (chdir(CONFIG_THTTPD_DATADIR) < 0) { ndbg("chdir to %s: %d\n", CONFIG_THTTPD_DATADIR, errno); exit(1); } #endif /* Initialize the timer package */ tmr_init(); /* Initialize the HTTP layer */ nvdbg("Calling httpd_initialize()\n"); hs = httpd_initialize(&sa); if (!hs) { ndbg("httpd_initialize() failed\n"); exit(1); } /* Set up the occasional timer */ if (tmr_create(NULL, occasional, JunkClientData, CONFIG_THTTPD_OCCASIONAL_MSEC * 1000L, 1) == NULL) { ndbg("tmr_create(occasional) failed\n"); exit(1); } /* Set up the idle timer */ if (tmr_create(NULL, idle, JunkClientData, 5 * 1000L, 1) == NULL) { ndbg("tmr_create(idle) failed\n"); exit(1); } /* Initialize our connections table */ connects = NEW(struct connect_s, AVAILABLE_FDS); if (connects == NULL) { ndbg("Out of memory allocating a struct connect_s\n"); exit(1); } for (cnum = 0; cnum < AVAILABLE_FDS; ++cnum) { connects[cnum].conn_state = CNST_FREE; connects[cnum].next = &connects[cnum + 1]; connects[cnum].hc = NULL; } connects[AVAILABLE_FDS-1].next = NULL; /* End of link list */ free_connections = connects; /* Beginning of the link list */ if (hs != NULL) { if (hs->listen_fd != -1) { fdwatch_add_fd(fw, hs->listen_fd, NULL); } } /* Main loop */ nvdbg("Entering the main loop\n"); (void)gettimeofday(&tv, NULL); for (;;) { /* Do the fd watch */ num_ready = fdwatch(fw, tmr_mstimeout(&tv)); if (num_ready < 0) { if (errno == EINTR || errno == EAGAIN) { /* Not errors... try again */ continue; } ndbg("fdwatch failed: %d\n", errno); exit(1); } (void)gettimeofday(&tv, NULL); if (num_ready == 0) { /* No fd's are ready - run the timers */ tmr_run(&tv); continue; } /* Is it a new connection? */ if (fdwatch_check_fd(fw, hs->listen_fd)) { if (!handle_newconnect(&tv, hs->listen_fd)) { /* Go around the loop and do another fdwatch, rather than * dropping through and processing existing connections. New * connections always get priority. */ continue; } } /* Find the connections that need servicing */ while ((conn = (struct connect_s*)fdwatch_get_next_client_data(fw)) != (struct connect_s*)-1) { if (conn) { hc = conn->hc; if (fdwatch_check_fd(fw, hc->conn_fd)) { nvdbg("Handle conn_state %d\n", conn->conn_state); switch (conn->conn_state) { case CNST_READING: { handle_read(conn, &tv); /* If a GET request was received and a file is ready to * be sent, then fall through to send the file. */ if (conn->conn_state != CNST_SENDING) { break; } } case CNST_SENDING: { /* Send a file -- this really should be performed on a * separate thread to keep the serve from locking up during * the write. */ handle_send(conn, &tv); } break; case CNST_LINGERING: { /* Linger close the connection */ handle_linger(conn, &tv); } break; } } } } tmr_run(&tv); } /* The main loop terminated */ shut_down(); ndbg("Exiting\n"); exit(0); } #endif /* CONFIG_THTTPD */