- djm@cvs.openbsd.org 2006/07/06 10:47:57

     [sftp-server.8 sftp-server.c]
     add commandline options to enable logging of transactions; ok markus@

3 files changed, 295 insertions, 58 deletions

diff --git a/ChangeLog b/ChangeLog
index 2e45ea65..e3e7ce82 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -38,6 +38,9 @@
    - djm@cvs.openbsd.org 2006/07/06 10:47:05
      [servconf.c servconf.h session.c sshd_config.5]
      support arguments to Subsystem commands; ok markus@
+   - djm@cvs.openbsd.org 2006/07/06 10:47:57
+     [sftp-server.8 sftp-server.c]
+     add commandline options to enable logging of transactions; ok markus@
 
 20060706
  - (dtucker) [configure.ac] Try AIX blibpath test in different order when
@@ -4771,4 +4774,4 @@
    - (djm) Trim deprecated options from INSTALL. Mention UsePAM
    - (djm) Fix quote handling in sftp; Patch from admorten AT umich.edu
 
-$Id: ChangeLog,v 1.4369 2006/07/10 10:36:47 djm Exp $
+$Id: ChangeLog,v 1.4370 2006/07/10 10:46:55 djm Exp $
diff --git a/sftp-server.8 b/sftp-server.8
index 42f5d437..da68e45f 100644
--- a/sftp-server.8
+++ b/sftp-server.8
@@ -1,4 +1,4 @@
-.\" $OpenBSD: sftp-server.8,v 1.10 2003/10/08 08:27:36 jmc Exp $
+.\" $OpenBSD: sftp-server.8,v 1.11 2006/07/06 10:47:57 djm Exp $
 .\"
 .\" Copyright (c) 2000 Markus Friedl.  All rights reserved.
 .\"
@@ -30,6 +30,8 @@
 .Nd SFTP server subsystem
 .Sh SYNOPSIS
 .Nm sftp-server
+.Op Fl f Ar log_facility
+.Op Fl l Ar log_level
 .Sh DESCRIPTION
 .Nm
 is a program that speaks the server side of SFTP protocol
@@ -40,9 +42,36 @@ is not intended to be called directly, but from
 using the
 .Cm Subsystem
 option.
+.Pp
+Command-line flags to
+.Nm
+should be specified in the
+.Cm Subsystem
+declaration.
 See
 .Xr sshd_config 5
 for more information.
+.Pp
+Valid options are:
+.Bl -tag -width Ds
+.It Fl f Ar log_facility
+Specifies the facility code that is used when logging messages from
+.Nm .
+The possible values are: DAEMON, USER, AUTH, LOCAL0, LOCAL1, LOCAL2,
+LOCAL3, LOCAL4, LOCAL5, LOCAL6, LOCAL7.
+The default is AUTH.
+.It Fl l Ar log_level
+Specifies which messages will be logged by
+.Nm .
+The possible values are:
+QUIET, FATAL, ERROR, INFO, VERBOSE, DEBUG, DEBUG1, DEBUG2, and DEBUG3.
+INFO and VERBOSE log transactions that
+.Nm
+performs on behalf of the client.
+DEBUG and DEBUG1 are equivalent.
+DEBUG2 and DEBUG3 each specify higher levels of debugging output.
+The default is ERROR.
+.El
 .Sh SEE ALSO
 .Xr sftp 1 ,
 .Xr ssh 1 ,
diff --git a/sftp-server.c b/sftp-server.c
index e842341c..e882216b 100644
--- a/sftp-server.c
+++ b/sftp-server.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sftp-server.c,v 1.57 2006/03/30 09:58:16 djm Exp $ */
+/* $OpenBSD: sftp-server.c,v 1.58 2006/07/06 10:47:57 djm Exp $ */
 /*
  * Copyright (c) 2000-2004 Markus Friedl.  All rights reserved.
  *
@@ -26,6 +26,7 @@
 #include "log.h"
 #include "xmalloc.h"
 #include "misc.h"
+#include "uidswap.h"
 
 #include "sftp.h"
 #include "sftp-common.h"
@@ -34,9 +35,13 @@
 #define get_int64()			buffer_get_int64(&iqueue);
 #define get_int()			buffer_get_int(&iqueue);
 #define get_string(lenp)		buffer_get_string(&iqueue, lenp);
-#define TRACE				debug
 
-extern char *__progname;
+/* Our verbosity */
+LogLevel log_level = SYSLOG_LEVEL_ERROR;
+
+/* Our client */
+struct passwd *pw = NULL;
+char *client_addr = NULL;
 
 /* input and output queue */
 Buffer iqueue;
@@ -108,6 +113,33 @@ flags_from_portable(int pflags)
 	return flags;
 }
 
+static const char *
+string_from_portable(int pflags)
+{
+	static char ret[128];
+
+	*ret = '\0';
+
+#define PAPPEND(str)	{				\
+		if (*ret != '\0')			\
+			strlcat(ret, ",", sizeof(ret));	\
+		strlcat(ret, str, sizeof(ret)); 	\
+	}
+
+	if (pflags & SSH2_FXF_READ)
+		PAPPEND("READ")
+	if (pflags & SSH2_FXF_WRITE)
+		PAPPEND("WRITE")
+	if (pflags & SSH2_FXF_CREAT)
+		PAPPEND("CREATE")
+	if (pflags & SSH2_FXF_TRUNC)
+		PAPPEND("TRUNCATE")
+	if (pflags & SSH2_FXF_EXCL)
+		PAPPEND("EXCL")
+
+	return ret;
+}
+
 static Attrib *
 get_attrib(void)
 {
@@ -122,6 +154,7 @@ struct Handle {
 	DIR *dirp;
 	int fd;
 	char *name;
+	u_int64_t bytes_read, bytes_write;
 };
 
 enum {
@@ -152,6 +185,7 @@ handle_new(int use, const char *name, int fd, DIR *dirp)
 			handles[i].dirp = dirp;
 			handles[i].fd = fd;
 			handles[i].name = xstrdup(name);
+			handles[i].bytes_read = handles[i].bytes_write = 0;
 			return i;
 		}
 	}
@@ -215,6 +249,36 @@ handle_to_fd(int handle)
 	return -1;
 }
 
+static void
+handle_update_read(int handle, ssize_t bytes)
+{
+	if (handle_is_ok(handle, HANDLE_FILE) && bytes > 0)
+		handles[handle].bytes_read += bytes;
+}
+
+static void
+handle_update_write(int handle, ssize_t bytes)
+{
+	if (handle_is_ok(handle, HANDLE_FILE) && bytes > 0)
+		handles[handle].bytes_write += bytes;
+}
+
+static u_int64_t
+handle_bytes_read(int handle)
+{
+	if (handle_is_ok(handle, HANDLE_FILE))
+		return (handles[handle].bytes_read);
+	return 0;
+}
+
+static u_int64_t
+handle_bytes_write(int handle)
+{
+	if (handle_is_ok(handle, HANDLE_FILE))
+		return (handles[handle].bytes_write);
+	return 0;
+}
+
 static int
 handle_close(int handle)
 {
@@ -234,6 +298,31 @@ handle_close(int handle)
 	return ret;
 }
 
+static void
+handle_log_close(int handle, char *emsg)
+{
+	if (handle_is_ok(handle, HANDLE_FILE)) {
+		logit("%s%sclose \"%s\" bytes read %llu written %llu",
+		    emsg == NULL ? "" : emsg, emsg == NULL ? "" : " ",
+		    handle_to_name(handle),
+		    handle_bytes_read(handle), handle_bytes_write(handle));
+	} else {
+		logit("%s%sclosedir \"%s\"",
+		    emsg == NULL ? "" : emsg, emsg == NULL ? "" : " ",
+		    handle_to_name(handle));
+	}
+}
+
+static void
+handle_log_exit(void)
+{
+	u_int i;
+
+	for (i = 0; i < sizeof(handles)/sizeof(Handle); i++)
+		if (handles[i].use != HANDLE_UNUSED)
+			handle_log_close(i, "forced");
+}
+
 static int
 get_handle(void)
 {
@@ -260,10 +349,9 @@ send_msg(Buffer *m)
 	buffer_consume(m, mlen);
 }
 
-static void
-send_status(u_int32_t id, u_int32_t status)
+static const char *
+status_to_message(u_int32_t status)
 {
-	Buffer msg;
 	const char *status_messages[] = {
 		"Success",			/* SSH_FX_OK */
 		"End of file",			/* SSH_FX_EOF */
@@ -276,15 +364,24 @@ send_status(u_int32_t id, u_int32_t status)
 		"Operation unsupported",	/* SSH_FX_OP_UNSUPPORTED */
 		"Unknown error"			/* Others */
 	};
+	return (status_messages[MIN(status,SSH2_FX_MAX)]);
+}
 
-	TRACE("sent status id %u error %u", id, status);
+static void
+send_status(u_int32_t id, u_int32_t status)
+{
+	Buffer msg;
+
+	debug3("request %u: sent status %u", id, status);
+	if (log_level > SYSLOG_LEVEL_VERBOSE ||
+	    (status != SSH2_FX_OK && status != SSH2_FX_EOF))
+		logit("sent status %s", status_to_message(status));
 	buffer_init(&msg);
 	buffer_put_char(&msg, SSH2_FXP_STATUS);
 	buffer_put_int(&msg, id);
 	buffer_put_int(&msg, status);
 	if (version >= 3) {
-		buffer_put_cstring(&msg,
-		    status_messages[MIN(status,SSH2_FX_MAX)]);
+		buffer_put_cstring(&msg, status_to_message(status));
 		buffer_put_cstring(&msg, "");
 	}
 	send_msg(&msg);
@@ -306,7 +403,7 @@ send_data_or_handle(char type, u_int32_t id, const char *data, int dlen)
 static void
 send_data(u_int32_t id, const char *data, int dlen)
 {
-	TRACE("sent data id %u len %d", id, dlen);
+	debug("request %u: sent data len %d", id, dlen);
 	send_data_or_handle(SSH2_FXP_DATA, id, data, dlen);
 }
 
@@ -317,7 +414,7 @@ send_handle(u_int32_t id, int handle)
 	int hlen;
 
 	handle_to_string(handle, &string, &hlen);
-	TRACE("sent handle id %u handle %d", id, handle);
+	debug("request %u: sent handle handle %d", id, handle);
 	send_data_or_handle(SSH2_FXP_HANDLE, id, string, hlen);
 	xfree(string);
 }
@@ -332,7 +429,7 @@ send_names(u_int32_t id, int count, const Stat *stats)
 	buffer_put_char(&msg, SSH2_FXP_NAME);
 	buffer_put_int(&msg, id);
 	buffer_put_int(&msg, count);
-	TRACE("sent names id %u count %d", id, count);
+	debug("request %u: sent names count %d", id, count);
 	for (i = 0; i < count; i++) {
 		buffer_put_cstring(&msg, stats[i].name);
 		buffer_put_cstring(&msg, stats[i].long_name);
@@ -347,7 +444,7 @@ send_attrib(u_int32_t id, const Attrib *a)
 {
 	Buffer msg;
 
-	TRACE("sent attrib id %u have 0x%x", id, a->flags);
+	debug("request %u: sent attrib have 0x%x", id, a->flags);
 	buffer_init(&msg);
 	buffer_put_char(&msg, SSH2_FXP_ATTRS);
 	buffer_put_int(&msg, id);
@@ -364,7 +461,7 @@ process_init(void)
 	Buffer msg;
 
 	version = get_int();
-	TRACE("client version %d", version);
+	verbose("received client version %d", version);
 	buffer_init(&msg);
 	buffer_put_char(&msg, SSH2_FXP_VERSION);
 	buffer_put_int(&msg, SSH2_FILEXFER_VERSION);
@@ -381,12 +478,14 @@ process_open(void)
 	int handle, fd, flags, mode, status = SSH2_FX_FAILURE;
 
 	id = get_int();
+	debug3("request %u: open flags %d", id, pflags);
 	name = get_string(NULL);
 	pflags = get_int();		/* portable flags */
 	a = get_attrib();
 	flags = flags_from_portable(pflags);
 	mode = (a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS) ? a->perm : 0666;
-	TRACE("open id %u name %s flags %d mode 0%o", id, name, pflags, mode);
+	logit("open \"%s\" flags %s mode 0%o",
+	    name, string_from_portable(pflags), mode);
 	fd = open(name, flags, mode);
 	if (fd < 0) {
 		status = errno_to_portable(errno);
@@ -412,7 +511,8 @@ process_close(void)
 
 	id = get_int();
 	handle = get_handle();
-	TRACE("close id %u handle %d", id, handle);
+	debug3("request %u: close handle %u", id, handle);
+	handle_log_close(handle, NULL);
 	ret = handle_close(handle);
 	status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
 	send_status(id, status);
@@ -431,11 +531,11 @@ process_read(void)
 	off = get_int64();
 	len = get_int();
 
-	TRACE("read id %u handle %d off %llu len %d", id, handle,
-	    (unsigned long long)off, len);
+	debug("request %u: read \"%s\" (handle %d) off %llu len %d",
+	    id, handle_to_name(handle), handle, (unsigned long long)off, len);
 	if (len > sizeof buf) {
 		len = sizeof buf;
-		logit("read change len %d", len);
+		debug2("read change len %d", len);
 	}
 	fd = handle_to_fd(handle);
 	if (fd >= 0) {
@@ -451,6 +551,7 @@ process_read(void)
 			} else {
 				send_data(id, buf, ret);
 				status = SSH2_FX_OK;
+				handle_update_read(handle, ret);
 			}
 		}
 	}
@@ -472,8 +573,8 @@ process_write(void)
 	off = get_int64();
 	data = get_string(&len);
 
-	TRACE("write id %u handle %d off %llu len %d", id, handle,
-	    (unsigned long long)off, len);
+	debug("request %u: write \"%s\" (handle %d) off %llu len %d",
+	    id, handle_to_name(handle), handle, (unsigned long long)off, len);
 	fd = handle_to_fd(handle);
 	if (fd >= 0) {
 		if (lseek(fd, off, SEEK_SET) < 0) {
@@ -487,8 +588,9 @@ process_write(void)
 				status = errno_to_portable(errno);
 			} else if ((size_t)ret == len) {
 				status = SSH2_FX_OK;
+				handle_update_write(handle, ret);
 			} else {
-				logit("nothing at all written");
+				debug2("nothing at all written");
 			}
 		}
 	}
@@ -507,7 +609,8 @@ process_do_stat(int do_lstat)
 
 	id = get_int();
 	name = get_string(NULL);
-	TRACE("%sstat id %u name %s", do_lstat ? "l" : "", id, name);
+	debug3("request %u: %sstat", id, do_lstat ? "l" : "");
+	verbose("%sstat name \"%s\"", do_lstat ? "l" : "", name);
 	ret = do_lstat ? lstat(name, &st) : stat(name, &st);
 	if (ret < 0) {
 		status = errno_to_portable(errno);
@@ -543,7 +646,8 @@ process_fstat(void)
 
 	id = get_int();
 	handle = get_handle();
-	TRACE("fstat id %u handle %d", id, handle);
+	debug("request %u: fstat \"%s\" (handle %u)",
+	    id, handle_to_name(handle), handle);
 	fd = handle_to_fd(handle);
 	if (fd  >= 0) {
 		ret = fstat(fd, &st);
@@ -582,23 +686,33 @@ process_setstat(void)
 	id = get_int();
 	name = get_string(NULL);
 	a = get_attrib();
-	TRACE("setstat id %u name %s", id, name);
+	debug("request %u: setstat name \"%s\"", id, name);
 	if (a->flags & SSH2_FILEXFER_ATTR_SIZE) {
+		logit("set \"%s\" size %llu", name, a->size);
 		ret = truncate(name, a->size);
 		if (ret == -1)
 			status = errno_to_portable(errno);
 	}
 	if (a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS) {
+		logit("set \"%s\" mode %04o", name, a->perm);
 		ret = chmod(name, a->perm & 0777);
 		if (ret == -1)
 			status = errno_to_portable(errno);
 	}
 	if (a->flags & SSH2_FILEXFER_ATTR_ACMODTIME) {
+		char buf[64];
+		time_t t = a->mtime;
+
+		strftime(buf, sizeof(buf), "%Y%m%d-%H:%M:%S",
+		    localtime(&t));
+		logit("set \"%s\" modtime %s", name, buf);
 		ret = utimes(name, attrib_to_tv(a));
 		if (ret == -1)
 			status = errno_to_portable(errno);
 	}
 	if (a->flags & SSH2_FILEXFER_ATTR_UIDGID) {
+		logit("set \"%s\" owner %lu group %lu", name,
+		    (u_long)a->uid, (u_long)a->gid);
 		ret = chown(name, a->uid, a->gid);
 		if (ret == -1)
 			status = errno_to_portable(errno);
@@ -614,23 +728,25 @@ process_fsetstat(void)
 	u_int32_t id;
 	int handle, fd, ret;
 	int status = SSH2_FX_OK;
-	char *name;
 
 	id = get_int();
 	handle = get_handle();
 	a = get_attrib();
-	TRACE("fsetstat id %u handle %d", id, handle);
+	debug("request %u: fsetstat handle %d", id, handle);
 	fd = handle_to_fd(handle);
-	name = handle_to_name(handle);
-	if (fd < 0 || name == NULL) {
+	if (fd < 0) {
 		status = SSH2_FX_FAILURE;
 	} else {
+		char *name = handle_to_name(handle);
+
 		if (a->flags & SSH2_FILEXFER_ATTR_SIZE) {
+			logit("set \"%s\" size %llu", name, a->size);
 			ret = ftruncate(fd, a->size);
 			if (ret == -1)
 				status = errno_to_portable(errno);
 		}
 		if (a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS) {
+			logit("set \"%s\" mode %04o", name, a->perm);
 #ifdef HAVE_FCHMOD
 			ret = fchmod(fd, a->perm & 0777);
 #else
@@ -640,6 +756,12 @@ process_fsetstat(void)
 				status = errno_to_portable(errno);
 		}
 		if (a->flags & SSH2_FILEXFER_ATTR_ACMODTIME) {
+			char buf[64];
+			time_t t = a->mtime;
+
+			strftime(buf, sizeof(buf), "%Y%m%d-%H:%M:%S",
+			    localtime(&t));
+			logit("set \"%s\" modtime %s", name, buf);
 #ifdef HAVE_FUTIMES
 			ret = futimes(fd, attrib_to_tv(a));
 #else
@@ -649,6 +771,8 @@ process_fsetstat(void)
 				status = errno_to_portable(errno);
 		}
 		if (a->flags & SSH2_FILEXFER_ATTR_UIDGID) {
+			logit("set \"%s\" owner %lu group %lu", name,
+			    (u_long)a->uid, (u_long)a->gid);
 #ifdef HAVE_FCHOWN
 			ret = fchown(fd, a->uid, a->gid);
 #else
@@ -671,7 +795,8 @@ process_opendir(void)
 
 	id = get_int();
 	path = get_string(NULL);
-	TRACE("opendir id %u path %s", id, path);
+	debug3("request %u: opendir", id);
+	logit("opendir \"%s\"", path);
 	dirp = opendir(path);
 	if (dirp == NULL) {
 		status = errno_to_portable(errno);
@@ -701,14 +826,15 @@ process_readdir(void)
 
 	id = get_int();
 	handle = get_handle();
-	TRACE("readdir id %u handle %d", id, handle);
+	debug("request %u: readdir \"%s\" (handle %d)", id,
+	    handle_to_name(handle), handle);
 	dirp = handle_to_dir(handle);
 	path = handle_to_name(handle);
 	if (dirp == NULL || path == NULL) {
 		send_status(id, SSH2_FX_FAILURE);
 	} else {
 		struct stat st;
-		char pathname[1024];
+		char pathname[MAXPATHLEN];
 		Stat *stats;
 		int nstats = 10, count = 0, i;
 
@@ -755,7 +881,8 @@ process_remove(void)
 
 	id = get_int();
 	name = get_string(NULL);
-	TRACE("remove id %u name %s", id, name);
+	debug3("request %u: remove", id);
+	logit("remove name \"%s\"", name);
 	ret = unlink(name);
 	status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
 	send_status(id, status);
@@ -775,7 +902,8 @@ process_mkdir(void)
 	a = get_attrib();
 	mode = (a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS) ?
 	    a->perm & 0777 : 0777;
-	TRACE("mkdir id %u name %s mode 0%o", id, name, mode);
+	debug3("request %u: mkdir", id);
+	logit("mkdir name \"%s\" mode 0%o", name, mode);
 	ret = mkdir(name, mode);
 	status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
 	send_status(id, status);
@@ -791,7 +919,8 @@ process_rmdir(void)
 
 	id = get_int();
 	name = get_string(NULL);
-	TRACE("rmdir id %u name %s", id, name);
+	debug3("request %u: rmdir", id);
+	logit("rmdir name \"%s\"", name);
 	ret = rmdir(name);
 	status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
 	send_status(id, status);
@@ -811,7 +940,8 @@ process_realpath(void)
 		xfree(path);
 		path = xstrdup(".");
 	}
-	TRACE("realpath id %u path %s", id, path);
+	debug3("request %u: realpath", id);
+	verbose("realpath \"%s\"", path);
 	if (realpath(path, resolvedname) == NULL) {
 		send_status(id, errno_to_portable(errno));
 	} else {
@@ -834,7 +964,8 @@ process_rename(void)
 	id = get_int();
 	oldpath = get_string(NULL);
 	newpath = get_string(NULL);
-	TRACE("rename id %u old %s new %s", id, oldpath, newpath);
+	debug3("request %u: rename", id);
+	logit("rename old \"%s\" new \"%s\"", oldpath, newpath);
 	status = SSH2_FX_FAILURE;
 	if (lstat(oldpath, &sb) == -1)
 		status = errno_to_portable(errno);
@@ -889,7 +1020,8 @@ process_readlink(void)
 
 	id = get_int();
 	path = get_string(NULL);
-	TRACE("readlink id %u path %s", id, path);
+	debug3("request %u: readlink", id);
+	verbose("readlink \"%s\"", path);
 	if ((len = readlink(path, buf, sizeof(buf) - 1)) == -1)
 		send_status(id, errno_to_portable(errno));
 	else {
@@ -913,7 +1045,8 @@ process_symlink(void)
 	id = get_int();
 	oldpath = get_string(NULL);
 	newpath = get_string(NULL);
-	TRACE("symlink id %u old %s new %s", id, oldpath, newpath);
+	debug3("request %u: symlink", id);
+	logit("symlink old \"%s\" new \"%s\"", oldpath, newpath);
 	/* this will fail if 'newpath' exists */
 	ret = symlink(oldpath, newpath);
 	status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
@@ -951,8 +1084,9 @@ process(void)
 	cp = buffer_ptr(&iqueue);
 	msg_len = get_u32(cp);
 	if (msg_len > SFTP_MAX_MSG_LENGTH) {
-		error("bad message ");
-		exit(11);
+		error("bad message from %s local user %s",
+		    client_addr, pw->pw_name);
+		cleanup_exit(11);
 	}
 	if (buf_len < msg_len + 4)
 		return;
@@ -1026,7 +1160,7 @@ process(void)
 	}
 	/* discard the remaining bytes from the current packet */
 	if (buf_len < buffer_len(&iqueue))
-		fatal("iqueue grows");
+		fatal("iqueue grew unexpectedly");
 	consumed = buf_len - buffer_len(&iqueue);
 	if (msg_len < consumed)
 		fatal("msg_len %d < consumed %d", msg_len, consumed);
@@ -1034,24 +1168,94 @@ process(void)
 		buffer_consume(&iqueue, msg_len - consumed);
 }
 
+/* Cleanup handler that logs active handles upon normal exit */
+void
+cleanup_exit(int i)
+{
+	if (pw != NULL && client_addr != NULL) {
+		handle_log_exit();
+		logit("session closed for local user %s from [%s]",
+		    pw->pw_name, client_addr);
+	}
+	_exit(i);
+}
+
+static void
+usage(void)
+{
+	extern char *__progname;
+
+	fprintf(stderr,
+	    "usage: %s [-he] [-l log_level] [-f log_facility]\n", __progname);
+	exit(1);
+}
+
 int
-main(int ac, char **av)
+main(int argc, char **argv)
 {
 	fd_set *rset, *wset;
-	int in, out, max;
+	int in, out, max, ch, skipargs = 0, log_stderr = 0;
 	ssize_t len, olen, set_size;
+	SyslogFacility log_facility = SYSLOG_FACILITY_AUTH;
+	char *cp;
+
+	extern int optind;
+	extern char *optarg;
+	extern char *__progname;
 
 	/* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
 	sanitise_stdfd();
 
-	/* XXX should use getopt */
+	__progname = ssh_get_progname(argv[0]);
+	log_init(__progname, log_level, log_facility, log_stderr);
+
+	while (!skipargs && (ch = getopt(argc, argv, "C:f:l:che")) != -1) {
+		switch (ch) {
+		case 'c':
+			/*
+			 * Ignore all arguments if we are invoked as a
+			 * shell using "sftp-server -c command" 
+			 */
+			skipargs = 1;
+			break;
+		case 'e':
+			log_stderr = 1;
+			break;
+		case 'l':
+			log_level = log_level_number(optarg);
+			if (log_level == SYSLOG_LEVEL_NOT_SET)
+				error("Invalid log level \"%s\"", optarg);
+			break;
+		case 'f':
+			log_facility = log_facility_number(optarg);
+			if (log_level == SYSLOG_FACILITY_NOT_SET)
+				error("Invalid log facility \"%s\"", optarg);
+			break;
+		case 'h':
+		default:
+			usage();
+		}
+	}
 
-	__progname = ssh_get_progname(av[0]);
-	handle_init();
+	log_init(__progname, log_level, log_facility, log_stderr);
 
-#ifdef DEBUG_SFTP_SERVER
-	log_init("sftp-server", SYSLOG_LEVEL_DEBUG1, SYSLOG_FACILITY_AUTH, 0);
-#endif
+	if ((cp = getenv("SSH_CONNECTION")) != NULL) {
+		client_addr = xstrdup(cp);
+		if ((cp = strchr(client_addr, ' ')) == NULL)
+			fatal("Malformed SSH_CONNECTION variable: \"%s\"",
+			    getenv("SSH_CONNECTION"));
+		*cp = '\0';
+	} else
+		client_addr = xstrdup("UNKNOWN");
+
+	if ((pw = getpwuid(getuid())) == NULL)
+		fatal("No user found for uid %lu", (u_long)getuid());
+	pw = pwcopy(pw);
+
+	logit("session opened for local user %s from [%s]",
+	    pw->pw_name, client_addr);
+
+	handle_init();
 
 	in = dup(STDIN_FILENO);
 	out = dup(STDOUT_FILENO);
@@ -1086,7 +1290,8 @@ main(int ac, char **av)
 		if (select(max+1, rset, wset, NULL, NULL) < 0) {
 			if (errno == EINTR)
 				continue;
-			exit(2);
+			error("select: %s", strerror(errno));
+			cleanup_exit(2);
 		}
 
 		/* copy stdin to iqueue */
@@ -1095,10 +1300,10 @@ main(int ac, char **av)
 			len = read(in, buf, sizeof buf);
 			if (len == 0) {
 				debug("read eof");
-				exit(0);
+				cleanup_exit(0);
 			} else if (len < 0) {
-				error("read error");
-				exit(1);
+				error("read: %s", strerror(errno));
+				cleanup_exit(1);
 			} else {
 				buffer_append(&iqueue, buf, len);
 			}
@@ -1107,8 +1312,8 @@ main(int ac, char **av)
 		if (FD_ISSET(out, wset)) {
 			len = write(out, buffer_ptr(&oqueue), olen);
 			if (len < 0) {
-				error("write error");
-				exit(1);
+				error("write: %s", strerror(errno));
+				cleanup_exit(1);
 			} else {
 				buffer_consume(&oqueue, len);
 			}