Initial import of OpenSSH post-2.2.0 snapshot dated 2000-09-09

1 files changed, 1068 insertions, 0 deletions

diff --git a/crypto/openssh/sftp-server.c b/crypto/openssh/sftp-server.c
new file mode 100644
index 0000000..018a03c
--- /dev/null
+++ b/crypto/openssh/sftp-server.c
@@ -0,0 +1,1068 @@
+/*
+ * Copyright (c) 2000 Markus Friedl.  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 ``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 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.
+ */
+#include "includes.h"
+RCSID("$OpenBSD: sftp-server.c,v 1.6 2000/09/07 20:27:53 deraadt Exp $");
+
+#include "ssh.h"
+#include "buffer.h"
+#include "bufaux.h"
+#include "getput.h"
+#include "xmalloc.h"
+
+/* version */
+#define	SSH_FILEXFER_VERSION		2
+
+/* client to server */
+#define	SSH_FXP_INIT			1
+#define	SSH_FXP_OPEN			3
+#define	SSH_FXP_CLOSE			4
+#define	SSH_FXP_READ			5
+#define	SSH_FXP_WRITE			6
+#define	SSH_FXP_LSTAT			7
+#define	SSH_FXP_FSTAT			8
+#define	SSH_FXP_SETSTAT			9
+#define	SSH_FXP_FSETSTAT		10
+#define	SSH_FXP_OPENDIR			11
+#define	SSH_FXP_READDIR			12
+#define	SSH_FXP_REMOVE			13
+#define	SSH_FXP_MKDIR			14
+#define	SSH_FXP_RMDIR			15
+#define	SSH_FXP_REALPATH		16
+#define	SSH_FXP_STAT			17
+#define	SSH_FXP_RENAME			18
+
+/* server to client */
+#define	SSH_FXP_VERSION			2
+#define	SSH_FXP_STATUS			101
+#define	SSH_FXP_HANDLE			102
+#define	SSH_FXP_DATA			103
+#define	SSH_FXP_NAME			104
+#define	SSH_FXP_ATTRS			105
+
+/* portable open modes */
+#define	SSH_FXF_READ			0x01
+#define	SSH_FXF_WRITE			0x02
+#define	SSH_FXF_APPEND			0x04
+#define	SSH_FXF_CREAT			0x08
+#define	SSH_FXF_TRUNC			0x10
+#define	SSH_FXF_EXCL			0x20
+
+/* attributes */
+#define	SSH_FXA_HAVE_SIZE		0x01
+#define	SSH_FXA_HAVE_UGID		0x02
+#define	SSH_FXA_HAVE_PERM		0x04
+#define	SSH_FXA_HAVE_TIME		0x08
+
+/* status messages */
+#define	SSH_FX_OK			0x00
+#define	SSH_FX_EOF			0x01
+#define	SSH_FX_NO_SUCH_FILE		0x02
+#define	SSH_FX_PERMISSION_DENIED	0x03
+#define	SSH_FX_FAILURE			0x04
+#define	SSH_FX_BAD_MESSAGE		0x05
+#define	SSH_FX_NO_CONNECTION		0x06
+#define	SSH_FX_CONNECTION_LOST		0x07
+
+
+/* helper */
+#define get_int()			buffer_get_int(&iqueue);
+#define get_string(lenp)		buffer_get_string(&iqueue, lenp);
+#define TRACE				log
+
+/* input and output queue */
+Buffer iqueue;
+Buffer oqueue;
+
+/* portable attibutes, etc. */
+
+typedef struct Attrib Attrib;
+typedef struct Stat Stat;
+
+struct Attrib
+{
+	u_int32_t	flags;
+	u_int32_t	size_high;
+	u_int32_t	size_low;
+	u_int64_t	size;
+	u_int32_t	uid;
+	u_int32_t	gid;
+	u_int32_t	perm;
+	u_int32_t	atime;
+	u_int32_t	mtime;
+};
+
+struct Stat
+{
+	char *name;
+	char *long_name;
+	Attrib attrib;
+};
+
+int
+errno_to_portable(int unixerrno)
+{
+	int ret = 0;
+	switch (unixerrno) {
+	case 0:
+		ret = SSH_FX_OK;
+		break;
+	case ENOENT:
+	case ENOTDIR:
+	case EBADF:
+	case ELOOP:
+		ret = SSH_FX_NO_SUCH_FILE;
+		break;
+	case EPERM:
+	case EACCES:
+	case EFAULT:
+		ret = SSH_FX_PERMISSION_DENIED;
+		break;
+	case ENAMETOOLONG:
+	case EINVAL:
+		ret = SSH_FX_BAD_MESSAGE;
+		break;
+	default:
+		ret = SSH_FX_FAILURE;
+		break;
+	}
+	return ret;
+}
+
+int
+flags_from_portable(int pflags)
+{
+	int flags = 0;
+	if (pflags & SSH_FXF_READ &&
+	    pflags & SSH_FXF_WRITE) {
+		flags = O_RDWR;
+	} else if (pflags & SSH_FXF_READ) {
+		flags = O_RDONLY;
+	} else if (pflags & SSH_FXF_WRITE) {
+		flags = O_WRONLY;
+	}
+	if (pflags & SSH_FXF_CREAT)
+		flags |= O_CREAT;
+	if (pflags & SSH_FXF_TRUNC)
+		flags |= O_TRUNC;
+	if (pflags & SSH_FXF_EXCL)
+		flags |= O_EXCL;
+	return flags;
+}
+
+void
+attrib_clear(Attrib *a)
+{
+	a->flags = 0;
+	a->size_low = 0;
+	a->size_high = 0;
+	a->size = 0;
+	a->uid = 0;
+	a->gid = 0;
+	a->perm = 0;
+	a->atime = 0;
+	a->mtime = 0;
+}
+
+Attrib *
+decode_attrib(Buffer *b)
+{
+	static Attrib a;
+	attrib_clear(&a);
+	a.flags = buffer_get_int(b);
+	if (a.flags & SSH_FXA_HAVE_SIZE) {
+		a.size_high = buffer_get_int(b);
+		a.size_low = buffer_get_int(b);
+		a.size = (((u_int64_t) a.size_high) << 32) + a.size_low;
+	}
+	if (a.flags & SSH_FXA_HAVE_UGID) {
+		a.uid = buffer_get_int(b);
+		a.gid = buffer_get_int(b);
+	}
+	if (a.flags & SSH_FXA_HAVE_PERM) {
+		a.perm = buffer_get_int(b);
+	}
+	if (a.flags & SSH_FXA_HAVE_TIME) {
+		a.atime = buffer_get_int(b);
+		a.mtime = buffer_get_int(b);
+	}
+	return &a;
+}
+
+void
+encode_attrib(Buffer *b, Attrib *a)
+{
+	buffer_put_int(b, a->flags);
+	if (a->flags & SSH_FXA_HAVE_SIZE) {
+		buffer_put_int(b, a->size_high);
+		buffer_put_int(b, a->size_low);
+	}
+	if (a->flags & SSH_FXA_HAVE_UGID) {
+		buffer_put_int(b, a->uid);
+		buffer_put_int(b, a->gid);
+	}
+	if (a->flags & SSH_FXA_HAVE_PERM) {
+		buffer_put_int(b, a->perm);
+	}
+	if (a->flags & SSH_FXA_HAVE_TIME) {
+		buffer_put_int(b, a->atime);
+		buffer_put_int(b, a->mtime);
+	}
+}
+
+Attrib *
+stat_to_attrib(struct stat *st)
+{
+	static Attrib a;
+	attrib_clear(&a);
+	a.flags = 0;
+	a.flags |= SSH_FXA_HAVE_SIZE;
+	a.size = st->st_size;
+	a.size_low = a.size;
+	a.size_high = (u_int32_t) (a.size >> 32);
+	a.flags |= SSH_FXA_HAVE_UGID;
+	a.uid = st->st_uid;
+	a.gid = st->st_gid;
+	a.flags |= SSH_FXA_HAVE_PERM;
+	a.perm = st->st_mode;
+	a.flags |= SSH_FXA_HAVE_TIME;
+	a.atime = st->st_atime;
+	a.mtime = st->st_mtime;
+	return &a;
+}
+
+Attrib *
+get_attrib(void)
+{
+	return decode_attrib(&iqueue);
+}
+
+/* handle handles */
+
+typedef struct Handle Handle;
+struct Handle {
+	int use;
+	DIR *dirp;
+	int fd;
+	char *name;
+};
+enum {
+	HANDLE_UNUSED,
+	HANDLE_DIR,
+	HANDLE_FILE
+};
+Handle	handles[100];
+
+void
+handle_init(void)
+{
+	int i;
+	for(i = 0; i < sizeof(handles)/sizeof(Handle); i++)
+		handles[i].use = HANDLE_UNUSED;
+}
+
+int
+handle_new(int use, char *name, int fd, DIR *dirp)
+{
+	int i;
+	for(i = 0; i < sizeof(handles)/sizeof(Handle); i++) {
+		if (handles[i].use == HANDLE_UNUSED) {
+			handles[i].use = use;
+			handles[i].dirp = dirp;
+			handles[i].fd = fd;
+			handles[i].name = name;
+			return i;
+		}
+	}
+	return -1;
+}
+
+int
+handle_is_ok(int i, int type)
+{
+	return i >= 0 && i < sizeof(handles)/sizeof(Handle) && handles[i].use == type;
+}
+
+int
+handle_to_string(int handle, char **stringp, int *hlenp)
+{
+	char buf[1024];
+	if (stringp == NULL || hlenp == NULL)
+		return -1;
+	snprintf(buf, sizeof buf, "%d", handle);
+	*stringp = xstrdup(buf);
+	*hlenp = strlen(*stringp);
+	return 0;
+}
+
+int
+handle_from_string(char *handle, u_int hlen)
+{
+/* XXX OVERFLOW ? */
+	char *ep;
+	long lval = strtol(handle, &ep, 10);
+	int val = lval;
+	if (*ep != '\0')
+		return -1;
+	if (handle_is_ok(val, HANDLE_FILE) ||
+	    handle_is_ok(val, HANDLE_DIR))
+		return val;
+	return -1;
+}
+
+char *
+handle_to_name(int handle)
+{
+	if (handle_is_ok(handle, HANDLE_DIR)||
+	    handle_is_ok(handle, HANDLE_FILE))
+		return handles[handle].name;
+	return NULL;
+}
+
+DIR *
+handle_to_dir(int handle)
+{
+	if (handle_is_ok(handle, HANDLE_DIR))
+		return handles[handle].dirp;
+	return NULL;
+}
+
+int
+handle_to_fd(int handle)
+{
+	if (handle_is_ok(handle, HANDLE_FILE)) 
+		return handles[handle].fd;
+	return -1;
+}
+
+int
+handle_close(int handle)
+{
+	int ret = -1;
+	if (handle_is_ok(handle, HANDLE_FILE)) {
+		ret = close(handles[handle].fd);
+		handles[handle].use = HANDLE_UNUSED;
+	} else if (handle_is_ok(handle, HANDLE_DIR)) {
+		ret = closedir(handles[handle].dirp);
+		handles[handle].use = HANDLE_UNUSED;
+	} else {
+		errno = ENOENT;
+	}
+	return ret;
+}
+
+int
+get_handle(void)
+{
+	char *handle;
+	int val;
+	u_int hlen;
+	handle = get_string(&hlen);
+	val = handle_from_string(handle, hlen);
+	xfree(handle);
+	return val;
+}
+
+/* send replies */
+
+void
+send_msg(Buffer *m)
+{
+	int mlen = buffer_len(m);
+	buffer_put_int(&oqueue, mlen);
+	buffer_append(&oqueue, buffer_ptr(m), mlen);
+	buffer_consume(m, mlen);
+}
+
+void
+send_status(u_int32_t id, u_int32_t error)
+{
+	Buffer msg;
+	TRACE("sent status id %d error %d", id, error);
+	buffer_init(&msg);
+	buffer_put_char(&msg, SSH_FXP_STATUS);
+	buffer_put_int(&msg, id);
+	buffer_put_int(&msg, error);
+	send_msg(&msg);
+	buffer_free(&msg);
+}
+void
+send_data_or_handle(char type, u_int32_t id, char *data, int dlen)
+{
+	Buffer msg;
+	buffer_init(&msg);
+	buffer_put_char(&msg, type);
+	buffer_put_int(&msg, id);
+	buffer_put_string(&msg, data, dlen);
+	send_msg(&msg);
+	buffer_free(&msg);
+}
+
+void
+send_data(u_int32_t id, char *data, int dlen)
+{
+	TRACE("sent data id %d len %d", id, dlen);
+	send_data_or_handle(SSH_FXP_DATA, id, data, dlen);
+}
+
+void
+send_handle(u_int32_t id, int handle)
+{
+	char *string;
+	int hlen;
+	handle_to_string(handle, &string, &hlen);
+	TRACE("sent handle id %d handle %d", id, handle);
+	send_data_or_handle(SSH_FXP_HANDLE, id, string, hlen);
+	xfree(string);
+}
+
+void
+send_names(u_int32_t id, int count, Stat *stats)
+{
+	Buffer msg;
+	int i;
+	buffer_init(&msg);
+	buffer_put_char(&msg, SSH_FXP_NAME);
+	buffer_put_int(&msg, id);
+	buffer_put_int(&msg, count);
+	TRACE("sent names id %d 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);
+		encode_attrib(&msg, &stats[i].attrib);
+	}
+	send_msg(&msg);
+	buffer_free(&msg);
+}
+
+void
+send_attrib(u_int32_t id, Attrib *a)
+{
+	Buffer msg;
+	TRACE("sent attrib id %d have 0x%x", id, a->flags);
+	buffer_init(&msg);
+	buffer_put_char(&msg, SSH_FXP_ATTRS);
+	buffer_put_int(&msg, id);
+	encode_attrib(&msg, a);
+	send_msg(&msg);
+	buffer_free(&msg);
+}
+
+/* parse incoming */
+
+void
+process_init(void)
+{
+	Buffer msg;
+	int version = buffer_get_int(&iqueue);
+
+	TRACE("client version %d", version);
+	buffer_init(&msg);
+	buffer_put_char(&msg, SSH_FXP_VERSION);
+	buffer_put_int(&msg, SSH_FILEXFER_VERSION);
+	send_msg(&msg);
+	buffer_free(&msg);
+}
+
+void
+process_open(void)
+{
+	u_int32_t id, pflags;
+	Attrib *a;
+	char *name;
+	int handle, fd, flags, mode, status = SSH_FX_FAILURE;
+
+	id = get_int();
+	name = get_string(NULL);
+	pflags = get_int();
+	a = get_attrib();
+	flags = flags_from_portable(pflags);
+	mode = (a->flags & SSH_FXA_HAVE_PERM) ? a->perm : 0666;
+	TRACE("open id %d name %s flags %d mode 0%o", id, name, pflags, mode);
+	fd = open(name, flags, mode);
+	if (fd < 0) {
+		status = errno_to_portable(errno);
+	} else {
+		handle = handle_new(HANDLE_FILE, xstrdup(name), fd, NULL);
+		if (handle < 0) {
+			close(fd);
+		} else {
+			send_handle(id, handle);
+			status = SSH_FX_OK;
+		}
+	}
+	if (status != SSH_FX_OK)
+		send_status(id, status);
+	xfree(name);
+}
+
+void
+process_close(void)
+{
+	u_int32_t id;
+	int handle, ret, status = SSH_FX_FAILURE;
+
+	id = get_int();
+	handle = get_handle();
+	TRACE("close id %d handle %d", id, handle);
+	ret = handle_close(handle);
+	status = (ret == -1) ? errno_to_portable(errno) : SSH_FX_OK;
+	send_status(id, status);
+}
+
+void
+process_read(void)
+{
+	char buf[64*1024];
+	u_int32_t id, off_high, off_low, len;
+	int handle, fd, ret, status = SSH_FX_FAILURE;
+	u_int64_t off;
+
+	id = get_int();
+	handle = get_handle();
+	off_high = get_int();
+	off_low = get_int();
+	len = get_int();
+
+	off = (((u_int64_t) off_high) << 32) + off_low;
+	TRACE("read id %d handle %d off %qd len %d", id, handle, off, len);
+	if (len > sizeof buf) {
+		len = sizeof buf;
+		log("read change len %d", len);
+	}
+	fd = handle_to_fd(handle);
+	if (fd >= 0) {
+		if (lseek(fd, off, SEEK_SET) < 0) {
+			error("process_read: seek failed");
+			status = errno_to_portable(errno);
+		} else {
+			ret = read(fd, buf, len);
+			if (ret < 0) {
+				status = errno_to_portable(errno);
+			} else if (ret == 0) {
+				status = SSH_FX_EOF;
+			} else {
+				send_data(id, buf, ret);
+				status = SSH_FX_OK;
+			}
+		}
+	}
+	if (status != SSH_FX_OK)
+		send_status(id, status);
+}
+
+void
+process_write(void)
+{
+	u_int32_t id, off_high, off_low;
+	u_int64_t off;
+	u_int len;
+	int handle, fd, ret, status = SSH_FX_FAILURE;
+	char *data;
+
+	id = get_int();
+	handle = get_handle();
+	off_high = get_int();
+	off_low = get_int();
+	data = get_string(&len);
+
+	off = (((u_int64_t) off_high) << 32) + off_low;
+	TRACE("write id %d handle %d off %qd len %d", id, handle, off, len);
+	fd = handle_to_fd(handle);
+	if (fd >= 0) {
+		if (lseek(fd, off, SEEK_SET) < 0) {
+			status = errno_to_portable(errno);
+			error("process_write: seek failed");
+		} else {
+/* XXX ATOMICIO ? */
+			ret = write(fd, data, len);
+			if (ret == -1) {
+				error("process_write: write failed");
+				status = errno_to_portable(errno);
+			} else if (ret == len) {
+				status = SSH_FX_OK;
+			} else {
+				log("nothing at all written");
+			}
+		}
+	}
+	send_status(id, status);
+	xfree(data);
+}
+
+void
+process_do_stat(int do_lstat)
+{
+	Attrib *a;
+	struct stat st;
+	u_int32_t id;
+	char *name;
+	int ret, status = SSH_FX_FAILURE;
+
+	id = get_int();
+	name = get_string(NULL);
+	TRACE("%sstat id %d name %s", do_lstat ? "l" : "", id, name);
+	ret = do_lstat ? lstat(name, &st) : stat(name, &st);
+	if (ret < 0) {
+		status = errno_to_portable(errno);
+	} else {
+		a = stat_to_attrib(&st);
+		send_attrib(id, a);
+		status = SSH_FX_OK;
+	}
+	if (status != SSH_FX_OK)
+		send_status(id, status);
+	xfree(name);
+}
+
+void
+process_stat(void)
+{
+	process_do_stat(0);
+}
+
+void
+process_lstat(void)
+{
+	process_do_stat(1);
+}
+
+void
+process_fstat(void)
+{
+	Attrib *a;
+	struct stat st;
+	u_int32_t id;
+	int fd, ret, handle, status = SSH_FX_FAILURE;
+
+	id = get_int();
+	handle = get_handle();
+	TRACE("fstat id %d handle %d", id, handle);
+	fd = handle_to_fd(handle);
+	if (fd  >= 0) {
+		ret = fstat(fd, &st);
+		if (ret < 0) {
+			status = errno_to_portable(errno);
+		} else {
+			a = stat_to_attrib(&st);
+			send_attrib(id, a);
+			status = SSH_FX_OK;
+		}
+	}
+	if (status != SSH_FX_OK)
+		send_status(id, status);
+}
+
+struct timeval *
+attrib_to_tv(Attrib *a)
+{
+	static struct timeval tv[2];
+	tv[0].tv_sec = a->atime;
+	tv[0].tv_usec = 0;
+	tv[1].tv_sec = a->mtime;
+	tv[1].tv_usec = 0;
+	return tv;
+}
+
+void
+process_setstat(void)
+{
+	Attrib *a;
+	u_int32_t id;
+	char *name;
+	int ret;
+	int status = SSH_FX_OK;
+
+	id = get_int();
+	name = get_string(NULL);
+	a = get_attrib();
+	TRACE("setstat id %d name %s", id, name);
+	if (a->flags & SSH_FXA_HAVE_PERM) {
+		ret = chmod(name, a->perm & 0777);
+		if (ret == -1)
+			status = errno_to_portable(errno);
+	}
+	if (a->flags & SSH_FXA_HAVE_TIME) {
+		ret = utimes(name, attrib_to_tv(a));
+		if (ret == -1)
+			status = errno_to_portable(errno);
+	}
+	send_status(id, status);
+	xfree(name);
+}
+
+void
+process_fsetstat(void)
+{
+	Attrib *a;
+	u_int32_t id;
+	int handle, fd, ret;
+	int status = SSH_FX_OK;
+
+	id = get_int();
+	handle = get_handle();
+	a = get_attrib();
+	TRACE("fsetstat id %d handle %d", id, handle);
+	fd = handle_to_fd(handle);
+	if (fd < 0) {
+		status = SSH_FX_FAILURE;
+	} else {
+		if (a->flags & SSH_FXA_HAVE_PERM) {
+			ret = fchmod(fd, a->perm & 0777);
+			if (ret == -1)
+				status = errno_to_portable(errno);
+		}
+		if (a->flags & SSH_FXA_HAVE_TIME) {
+			ret = futimes(fd, attrib_to_tv(a));
+			if (ret == -1)
+				status = errno_to_portable(errno);
+		}
+	}
+	send_status(id, status);
+}
+
+void
+process_opendir(void)
+{
+	DIR *dirp = NULL;
+	char *path;
+	int handle, status = SSH_FX_FAILURE;
+	u_int32_t id;
+
+	id = get_int();
+	path = get_string(NULL);
+	TRACE("opendir id %d path %s", id, path);
+	dirp = opendir(path); 
+	if (dirp == NULL) {
+		status = errno_to_portable(errno);
+	} else {
+		handle = handle_new(HANDLE_DIR, xstrdup(path), 0, dirp);
+		if (handle < 0) {
+			closedir(dirp);
+		} else {
+			send_handle(id, handle);
+			status = SSH_FX_OK;
+		}
+		
+	}
+	if (status != SSH_FX_OK)
+		send_status(id, status);
+	xfree(path);
+}
+
+char *
+ls_file(char *name, struct stat *st)
+{
+	char buf[1024];
+	snprintf(buf, sizeof buf, "0%o %d %d %qd %d %s",
+	    st->st_mode, st->st_uid, st->st_gid, (long long)st->st_size,(int) st->st_mtime,
+	    name);
+	return xstrdup(buf);
+}
+
+void
+process_readdir(void)
+{
+	DIR *dirp;
+	struct dirent *dp;
+	char *path;
+	int handle;
+	u_int32_t id;
+
+	id = get_int();
+	handle = get_handle();
+	TRACE("readdir id %d handle %d", id, handle);
+	dirp = handle_to_dir(handle);
+	path = handle_to_name(handle);
+	if (dirp == NULL || path == NULL) {
+		send_status(id, SSH_FX_FAILURE);
+	} else {
+		Attrib *a;
+		struct stat st;
+		char pathname[1024];
+		Stat *stats;
+		int nstats = 10, count = 0, i;
+		stats = xmalloc(nstats * sizeof(Stat));
+		while ((dp = readdir(dirp)) != NULL) {
+			if (count >= nstats) {
+				nstats *= 2;
+				stats = xrealloc(stats, nstats * sizeof(Stat));
+			}
+/* XXX OVERFLOW ? */
+			snprintf(pathname, sizeof pathname,
+			    "%s/%s", path, dp->d_name);
+			if (lstat(pathname, &st) < 0)
+				continue;
+			a = stat_to_attrib(&st);
+			stats[count].attrib = *a;
+			stats[count].name = xstrdup(dp->d_name);
+			stats[count].long_name = ls_file(dp->d_name, &st);
+			count++;
+			/* send up to 100 entries in one message */
+			if (count == 100)
+				break;
+		}
+		send_names(id, count, stats);
+		for(i = 0; i < count; i++) {
+			xfree(stats[i].name);
+			xfree(stats[i].long_name);
+		}
+		xfree(stats);
+	}
+}
+
+void
+process_remove(void)
+{
+	char *name;
+	u_int32_t id;
+	int status = SSH_FX_FAILURE;
+	int ret;
+
+	id = get_int();
+	name = get_string(NULL);
+	TRACE("remove id %d name %s", id, name);
+	ret = remove(name);
+	status = (ret == -1) ? errno_to_portable(errno) : SSH_FX_OK;
+	send_status(id, status);
+	xfree(name);
+}
+
+void
+process_mkdir(void)
+{
+	Attrib *a;
+	u_int32_t id;
+	char *name;
+	int ret, mode, status = SSH_FX_FAILURE;
+
+	id = get_int();
+	name = get_string(NULL);
+	a = get_attrib();
+	mode = (a->flags & SSH_FXA_HAVE_PERM) ? a->perm & 0777 : 0777;
+	TRACE("mkdir id %d name %s mode 0%o", id, name, mode);
+	ret = mkdir(name, mode);
+	status = (ret == -1) ? errno_to_portable(errno) : SSH_FX_OK;
+	send_status(id, status);
+	xfree(name);
+}
+
+void
+process_rmdir(void)
+{
+	u_int32_t id;
+	char *name;
+	int ret, status;
+
+	id = get_int();
+	name = get_string(NULL);
+	TRACE("rmdir id %d name %s", id, name);
+	ret = rmdir(name);
+	status = (ret == -1) ? errno_to_portable(errno) : SSH_FX_OK;
+	send_status(id, status);
+	xfree(name);
+}
+
+void
+process_realpath(void)
+{
+	char resolvedname[MAXPATHLEN];
+	u_int32_t id;
+	char *path;
+
+	id = get_int();
+	path = get_string(NULL);
+	TRACE("realpath id %d path %s", id, path);
+	if (realpath(path, resolvedname) == NULL) {
+		send_status(id, errno_to_portable(errno));
+	} else {
+		Stat s;
+		attrib_clear(&s.attrib);
+		s.name = s.long_name = resolvedname;
+		send_names(id, 1, &s);
+	}
+	xfree(path);
+}
+
+void
+process_rename(void)
+{
+	u_int32_t id;
+	char *oldpath, *newpath;
+	int ret, status;
+
+	id = get_int();
+	oldpath = get_string(NULL);
+	newpath = get_string(NULL);
+	TRACE("rename id %d old %s new %s", id, oldpath, newpath);
+	ret = rename(oldpath, newpath);
+	status = (ret == -1) ? errno_to_portable(errno) : SSH_FX_OK;
+	send_status(id, status);
+	xfree(oldpath);
+	xfree(newpath);
+}
+
+
+/* stolen from ssh-agent */
+
+void
+process(void)
+{
+	unsigned int msg_len;
+	unsigned int type;
+	unsigned char *cp;
+
+	if (buffer_len(&iqueue) < 5)
+		return;		/* Incomplete message. */
+	cp = (unsigned char *) buffer_ptr(&iqueue);
+	msg_len = GET_32BIT(cp);
+	if (msg_len > 256 * 1024) {
+		error("bad message ");
+		exit(11);
+	}
+	if (buffer_len(&iqueue) < msg_len + 4)
+		return;
+	buffer_consume(&iqueue, 4);
+	type = buffer_get_char(&iqueue);
+	switch (type) {
+	case SSH_FXP_INIT:
+		process_init();
+		break;
+	case SSH_FXP_OPEN:
+		process_open();
+		break;
+	case SSH_FXP_CLOSE:
+		process_close();
+		break;
+	case SSH_FXP_READ:
+		process_read();
+		break;
+	case SSH_FXP_WRITE:
+		process_write();
+		break;
+	case SSH_FXP_LSTAT:
+		process_lstat();
+		break;
+	case SSH_FXP_FSTAT:
+		process_fstat();
+		break;
+	case SSH_FXP_SETSTAT:
+		process_setstat();
+		break;
+	case SSH_FXP_FSETSTAT:
+		process_fsetstat();
+		break;
+	case SSH_FXP_OPENDIR:
+		process_opendir();
+		break;
+	case SSH_FXP_READDIR:
+		process_readdir();
+		break;
+	case SSH_FXP_REMOVE:
+		process_remove();
+		break;
+	case SSH_FXP_MKDIR:
+		process_mkdir();
+		break;
+	case SSH_FXP_RMDIR:
+		process_rmdir();
+		break;
+	case SSH_FXP_REALPATH:
+		process_realpath();
+		break;
+	case SSH_FXP_STAT:
+		process_stat();
+		break;
+	case SSH_FXP_RENAME:
+		process_rename();
+		break;
+	default:
+		error("Unknown message %d", type);
+		break;
+	}
+}
+
+int
+main(int ac, char **av)
+{
+	fd_set rset, wset;
+	int in, out, max;
+	ssize_t len, olen;
+
+	handle_init();
+
+	in = dup(STDIN_FILENO);
+	out = dup(STDOUT_FILENO);
+
+	max = 0;
+	if (in > max)
+		max = in;
+	if (out > max)
+		max = out;
+
+	buffer_init(&iqueue);
+	buffer_init(&oqueue);
+
+	for (;;) {
+		FD_ZERO(&rset);
+		FD_ZERO(&wset);
+
+		FD_SET(in, &rset);
+		olen = buffer_len(&oqueue);
+		if (olen > 0)
+			FD_SET(out, &wset);
+
+		if (select(max+1, &rset, &wset, NULL, NULL) < 0) {
+			if (errno == EINTR)
+				continue;
+			exit(2);
+		}
+
+		/* copy stdin to iqueue */
+		if (FD_ISSET(in, &rset)) {
+			char buf[4*4096];
+			len = read(in, buf, sizeof buf);
+			if (len == 0) {
+				debug("read eof");
+				exit(0);
+			} else if (len < 0) {
+				error("read error");
+				exit(1);
+			} else {
+				buffer_append(&iqueue, buf, len);
+			}
+		}
+		/* send oqueue to stdout */
+		if (FD_ISSET(out, &wset)) {
+			len = write(out, buffer_ptr(&oqueue), olen);
+			if (len < 0) {
+				error("write error");
+				exit(1);
+			} else {
+				buffer_consume(&oqueue, len);
+			}
+		}
+		/* process requests from client */
+		process();
+	}
+}