diff svr-session.c @ 4:fe6bca95afa7

Makefile.in contains updated files required
author Matt Johnston <matt@ucc.asn.au>
date Tue, 01 Jun 2004 02:46:09 +0000
parents
children bc6477a6c393
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/svr-session.c	Tue Jun 01 02:46:09 2004 +0000
@@ -0,0 +1,238 @@
+/*
+ * Dropbear - a SSH2 server
+ * 
+ * Copyright (c) 2002,2003 Matt Johnston
+ * All rights reserved.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE. */
+
+#include "includes.h"
+#include "session.h"
+#include "dbutil.h"
+#include "packet.h"
+#include "algo.h"
+#include "buffer.h"
+#include "dss.h"
+#include "ssh.h"
+#include "random.h"
+#include "kex.h"
+#include "channel.h"
+#include "chansession.h"
+#include "atomicio.h"
+
+static void svr_remoteclosed();
+static void svr_dropbear_exit(int exitcode, const char* format, va_list param);
+static void svr_dropbear_log(int priority, const char* format, va_list param);
+
+struct serversession svr_ses;
+
+void svr_session(int sock, runopts *opts, int childpipe, 
+		struct sockaddr* remoteaddr) {
+
+	fd_set readfd, writefd;
+	struct timeval timeout;
+	int val;
+	
+	crypto_init();
+	common_session_init(sock, opts);
+
+	ses.remoteaddr = remoteaddr;
+	ses.remotehost = getaddrhostname(remoteaddr);
+
+	/* Initialise server specific parts of the session */
+	svr_ses.childpipe = childpipe;
+	authinitialise();
+	svr_chansessinitialise();
+
+	if (gettimeofday(&timeout, 0) < 0) {
+		dropbear_exit("Error getting time");
+	}
+
+	ses.connecttimeout = timeout.tv_sec + AUTH_TIMEOUT;
+
+	/* set up messages etc */
+	session_remoteclosed = svr_remoteclosed;
+	_dropbear_exit = svr_dropbear_exit;
+	_dropbear_log = svr_dropbear_log;
+
+	/* We're ready to go now */
+	sessinitdone = 1;
+
+	/* exchange identification, version etc */
+	session_identification();
+
+	seedrandom();
+
+	/* start off with key exchange */
+	send_msg_kexinit();
+
+	FD_ZERO(&readfd);
+	FD_ZERO(&writefd);
+
+	/* main loop, select()s for all sockets in use */
+	for(;;) {
+
+		timeout.tv_sec = SELECT_TIMEOUT;
+		timeout.tv_usec = 0;
+		FD_ZERO(&writefd);
+		FD_ZERO(&readfd);
+		assert(ses.payload == NULL);
+		if (ses.sock != -1) {
+			FD_SET(ses.sock, &readfd);
+			if (!isempty(&ses.writequeue)) {
+				FD_SET(ses.sock, &writefd);
+			}
+		}
+
+		/* set up for channels which require reading/writing */
+		if (ses.dataallowed) {
+			setchannelfds(&readfd, &writefd);
+		}
+		val = select(ses.maxfd+1, &readfd, &writefd, NULL, &timeout);
+
+		if (exitflag) {
+			dropbear_exit("Terminated by signal");
+		}
+		
+		if (val < 0) {
+			if (errno == EINTR) {
+				continue;
+			} else {
+				dropbear_exit("Error in select");
+			}
+		}
+
+		/* check for auth timeout, rekeying required etc */
+		checktimeouts();
+		
+		if (val == 0) {
+			/* timeout */
+			TRACE(("select timeout"));
+			continue;
+		}
+
+		/* process session socket's incoming/outgoing data */
+		if (ses.sock != -1) {
+			if (FD_ISSET(ses.sock, &writefd) && !isempty(&ses.writequeue)) {
+				write_packet();
+			}
+
+			if (FD_ISSET(ses.sock, &readfd)) {
+				read_packet();
+			}
+			
+			/* Process the decrypted packet. After this, the read buffer
+			 * will be ready for a new packet */
+			if (ses.payload != NULL) {
+				svr_process_packet();
+			}
+		}
+
+		/* process pipes etc for the channels, ses.dataallowed == 0
+		 * during rekeying ) */
+		if (ses.dataallowed) {
+			channelio(&readfd, &writefd);
+		}
+
+	} /* for(;;) */
+}
+
+
+
+/* called when the remote side closes the connection */
+static void svr_remoteclosed() {
+
+	close(ses.sock);
+	ses.sock = -1;
+	dropbear_close("Exited normally");
+
+}
+
+/* failure exit - format must be <= 100 chars */
+static void svr_dropbear_exit(int exitcode, const char* format, va_list param) {
+
+	char fmtbuf[300];
+
+	if (!sessinitdone) {
+		/* before session init */
+		snprintf(fmtbuf, sizeof(fmtbuf), 
+				"premature exit: %s", format);
+	} else if (svr_ses.authstate.authdone) {
+		/* user has authenticated */
+		snprintf(fmtbuf, sizeof(fmtbuf),
+				"exit after auth (%s): %s", 
+				svr_ses.authstate.printableuser, format);
+	} else if (svr_ses.authstate.printableuser) {
+		/* we have a potential user */
+		snprintf(fmtbuf, sizeof(fmtbuf), 
+				"exit before auth (user '%s', %d fails): %s",
+				svr_ses.authstate.printableuser, svr_ses.authstate.failcount, format);
+	} else {
+		/* before userauth */
+		snprintf(fmtbuf, sizeof(fmtbuf), 
+				"exit before auth: %s", format);
+	}
+
+	if (errno != 0) {
+		/* XXX - is this valid? */
+		snprintf(fmtbuf, sizeof(fmtbuf), "%s [%d %s]", fmtbuf, 
+				errno, strerror(errno));
+	}
+
+	_dropbear_log(LOG_INFO, fmtbuf, param);
+
+	/* must be after we've done with username etc */
+	common_session_cleanup();
+
+	exit(exitcode);
+
+}
+
+/* priority is priority as with syslog() */
+static void svr_dropbear_log(int priority, const char* format, va_list param) {
+
+	char printbuf[1024];
+	char datestr[20];
+	time_t timesec;
+	int havetrace = 0;
+
+	vsnprintf(printbuf, sizeof(printbuf), format, param);
+
+#ifndef DISABLE_SYSLOG
+	if (usingsyslog) {
+		syslog(priority, "%s", printbuf);
+	}
+#endif
+
+	/* if we are using DEBUG_TRACE, we want to print to stderr even if
+	 * syslog is used, so it is included in error reports */
+#ifdef DEBUG_TRACE
+	havetrace = 1;
+#endif
+
+	if (!usingsyslog || havetrace)
+	{
+		timesec = time(NULL);
+		if (strftime(datestr, sizeof(datestr), "%b %d %H:%M:%S", 
+					localtime(&timesec)) == 0) {
+			datestr[0] = '?'; datestr[1] = '\0';
+		}
+		fprintf(stderr, "[%d] %s %s\n", getpid(), datestr, printbuf);
+	}
+}