sftp-client.c

OpenSSL Source code for SFTP, SSH, and many others

	if (status != SSH2_FX_OK)
		error("Couldn't fsetstat: %s", fx2txt(status));

	return(status);
}

char *
do_realpath(struct sftp_conn *conn, char *path)
{
	Buffer msg;
	u_int type, expected_id, count, id;
	char *filename, *longname;
	Attrib *a;

	expected_id = id = conn->msg_id++;
	send_string_request(conn->fd_out, id, SSH2_FXP_REALPATH, path,
	    strlen(path));

	buffer_init(&msg);

	get_msg(conn->fd_in, &msg);
	type = buffer_get_char(&msg);
	id = buffer_get_int(&msg);

	if (id != expected_id)
		fatal("ID mismatch (%d != %d)", id, expected_id);

	if (type == SSH2_FXP_STATUS) {
		u_int status = buffer_get_int(&msg);

		error("Couldn't canonicalise: %s", fx2txt(status));
		return(NULL);
	} else if (type != SSH2_FXP_NAME)
		fatal("Expected SSH2_FXP_NAME(%d) packet, got %d",
		    SSH2_FXP_NAME, type);

	count = buffer_get_int(&msg);
	if (count != 1)
		fatal("Got multiple names (%d) from SSH_FXP_REALPATH", count);

	filename = buffer_get_string(&msg, NULL);
	longname = buffer_get_string(&msg, NULL);
	a = decode_attrib(&msg);

	debug3("SSH_FXP_REALPATH %s -> %s", path, filename);

	xfree(longname);

	buffer_free(&msg);

	return(filename);
}

int
do_rename(struct sftp_conn *conn, char *oldpath, char *newpath)
{
	Buffer msg;
	u_int status, id;

	buffer_init(&msg);

	/* Send rename request */
	id = conn->msg_id++;
	buffer_put_char(&msg, SSH2_FXP_RENAME);
	buffer_put_int(&msg, id);
	buffer_put_cstring(&msg, oldpath);
	buffer_put_cstring(&msg, newpath);
	send_msg(conn->fd_out, &msg);
	debug3("Sent message SSH2_FXP_RENAME \"%s\" -> \"%s\"", oldpath,
	    newpath);
	buffer_free(&msg);

	status = get_status(conn->fd_in, id);
	if (status != SSH2_FX_OK)
		error("Couldn't rename file \"%s\" to \"%s\": %s", oldpath,
		    newpath, fx2txt(status));

	return(status);
}

int
do_symlink(struct sftp_conn *conn, char *oldpath, char *newpath)
{
	Buffer msg;
	u_int status, id;

	if (conn->version < 3) {
		error("This server does not support the symlink operation");
		return(SSH2_FX_OP_UNSUPPORTED);
	}

	buffer_init(&msg);

	/* Send rename request */
	id = conn->msg_id++;
	buffer_put_char(&msg, SSH2_FXP_SYMLINK);
	buffer_put_int(&msg, id);
	buffer_put_cstring(&msg, oldpath);
	buffer_put_cstring(&msg, newpath);
	send_msg(conn->fd_out, &msg);
	debug3("Sent message SSH2_FXP_SYMLINK \"%s\" -> \"%s\"", oldpath,
	    newpath);
	buffer_free(&msg);

	status = get_status(conn->fd_in, id);
	if (status != SSH2_FX_OK)
		error("Couldn't rename file \"%s\" to \"%s\": %s", oldpath,
		    newpath, fx2txt(status));

	return(status);
}

char *
do_readlink(struct sftp_conn *conn, char *path)
{
	Buffer msg;
	u_int type, expected_id, count, id;
	char *filename, *longname;
	Attrib *a;

	expected_id = id = conn->msg_id++;
	send_string_request(conn->fd_out, id, SSH2_FXP_READLINK, path,
	    strlen(path));

	buffer_init(&msg);

	get_msg(conn->fd_in, &msg);
	type = buffer_get_char(&msg);
	id = buffer_get_int(&msg);

	if (id != expected_id)
		fatal("ID mismatch (%d != %d)", id, expected_id);

	if (type == SSH2_FXP_STATUS) {
		u_int status = buffer_get_int(&msg);

		error("Couldn't readlink: %s", fx2txt(status));
		return(NULL);
	} else if (type != SSH2_FXP_NAME)
		fatal("Expected SSH2_FXP_NAME(%d) packet, got %d",
		    SSH2_FXP_NAME, type);

	count = buffer_get_int(&msg);
	if (count != 1)
		fatal("Got multiple names (%d) from SSH_FXP_READLINK", count);

	filename = buffer_get_string(&msg, NULL);
	longname = buffer_get_string(&msg, NULL);
	a = decode_attrib(&msg);

	debug3("SSH_FXP_READLINK %s -> %s", path, filename);

	xfree(longname);

	buffer_free(&msg);

	return(filename);
}

static void
send_read_request(int fd_out, u_int id, u_int64_t offset, u_int len,
    char *handle, u_int handle_len)
{
	Buffer msg;

	buffer_init(&msg);
	buffer_clear(&msg);
	buffer_put_char(&msg, SSH2_FXP_READ);
	buffer_put_int(&msg, id);
	buffer_put_string(&msg, handle, handle_len);
	buffer_put_int64(&msg, offset);
	buffer_put_int(&msg, len);
	send_msg(fd_out, &msg);
	buffer_free(&msg);
}

int
do_download(struct sftp_conn *conn, char *remote_path, char *local_path,
    int pflag)
{
	Attrib junk, *a;
	Buffer msg;
	char *handle;
	int local_fd, status, num_req, max_req, write_error;
	int read_error, write_errno;
	u_int64_t offset, size;
	u_int handle_len, mode, type, id, buflen;
	struct request {
		u_int id;
		u_int len;
		u_int64_t offset;
		TAILQ_ENTRY(request) tq;
	};
	TAILQ_HEAD(reqhead, request) requests;
	struct request *req;

	TAILQ_INIT(&requests);

	a = do_stat(conn, remote_path, 0);
	if (a == NULL)
		return(-1);

	/* XXX: should we preserve set[ug]id? */
	if (a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS)
		mode = S_IWRITE | (a->perm & 0777);
	else
		mode = 0666;

	if ((a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS) &&
	    (a->perm & S_IFDIR)) {
		error("Cannot download a directory: %s", remote_path);
		return(-1);
	}

	if (a->flags & SSH2_FILEXFER_ATTR_SIZE)
		size = a->size;
	else
		size = 0;

	buflen = conn->transfer_buflen;
	buffer_init(&msg);

	/* Send open request */
	id = conn->msg_id++;
	buffer_put_char(&msg, SSH2_FXP_OPEN);
	buffer_put_int(&msg, id);
	buffer_put_cstring(&msg, remote_path);
	buffer_put_int(&msg, SSH2_FXF_READ);
	attrib_clear(&junk); /* Send empty attributes */
	encode_attrib(&msg, &junk);
	send_msg(conn->fd_out, &msg);
	debug3("Sent message SSH2_FXP_OPEN I:%d P:%s", id, remote_path);

	handle = get_handle(conn->fd_in, id, &handle_len);
	if (handle == NULL) {
		buffer_free(&msg);
		return(-1);
	}

	local_fd = open(local_path, O_WRONLY | O_CREAT | O_TRUNC, mode);
	if (local_fd == -1) {
		error("Couldn't open local file \"%s\" for writing: %s",
		    local_path, strerror(errno));
		buffer_free(&msg);
		xfree(handle);
		return(-1);
	}

	/* Read from remote and write to local */
	write_error = read_error = write_errno = num_req = offset = 0;
	max_req = 1;
	while (num_req > 0 || max_req > 0) {
		char *data;
		u_int len;

		/* Send some more requests */
		while (num_req < max_req) {
			debug3("Request range %llu -> %llu (%d/%d)",
			    (unsigned long long)offset,
			    (unsigned long long)offset + buflen - 1,
			    num_req, max_req);
			req = xmalloc(sizeof(*req));
			req->id = conn->msg_id++;
			req->len = buflen;
			req->offset = offset;
			offset += buflen;
			num_req++;
			TAILQ_INSERT_TAIL(&requests, req, tq);
			send_read_request(conn->fd_out, req->id, req->offset,
			    req->len, handle, handle_len);
		}

		buffer_clear(&msg);
		get_msg(conn->fd_in, &msg);
		type = buffer_get_char(&msg);
		id = buffer_get_int(&msg);
		debug3("Received reply T:%d I:%d R:%d", type, id, max_req);

		/* Find the request in our queue */
		for(req = TAILQ_FIRST(&requests);
		    req != NULL && req->id != id;
		    req = TAILQ_NEXT(req, tq))
			;
		if (req == NULL)
			fatal("Unexpected reply %u", id);

		switch (type) {
		case SSH2_FXP_STATUS:
			status = buffer_get_int(&msg);
			if (status != SSH2_FX_EOF)
				read_error = 1;
			max_req = 0;
			TAILQ_REMOVE(&requests, req, tq);
			xfree(req);
			num_req--;
			break;
		case SSH2_FXP_DATA:
			data = buffer_get_string(&msg, &len);
			debug3("Received data %llu -> %llu",
			    (unsigned long long)req->offset,
			    (unsigned long long)req->offset + len - 1);
			if (len > req->len)
				fatal("Received more data than asked for "
				      "%d > %d", len, req->len);
			if ((lseek(local_fd, req->offset, SEEK_SET) == -1 ||
			     atomicio(write, local_fd, data, len) != len) &&
			    !write_error) {
				write_errno = errno;
				write_error = 1;
				max_req = 0;
			}
			xfree(data);

			if (len == req->len) {
				TAILQ_REMOVE(&requests, req, tq);
				xfree(req);
				num_req--;
			} else {
				/* Resend the request for the missing data */
				debug3("Short data block, re-requesting "
				    "%llu -> %llu (%2d)",
				    (unsigned long long)req->offset + len,
				    (unsigned long long)req->offset +
				    req->len - 1, num_req);
				req->id = conn->msg_id++;
				req->len -= len;
				req->offset += len;
				send_read_request(conn->fd_out, req->id,
				    req->offset, req->len, handle, handle_len);
				/* Reduce the request size */
				if (len < buflen)
					buflen = MAX(MIN_READ_SIZE, len);
			}
			if (max_req > 0) { /* max_req = 0 iff EOF received */
				if (size > 0 && offset > size) {
					/* Only one request at a time
					 * after the expected EOF */
					debug3("Finish at %llu (%2d)",
					    (unsigned long long)offset,
					    num_req);
					max_req = 1;
				}
				else if (max_req < conn->num_requests + 1) {
					++max_req;
				}
			}
			break;
		default:
			fatal("Expected SSH2_FXP_DATA(%d) packet, got %d",
			    SSH2_FXP_DATA, type);
		}
	}

	/* Sanity check */
	if (TAILQ_FIRST(&requests) != NULL)
		fatal("Transfer complete, but requests still in queue");

	if (read_error) {
		error("Couldn't read from remote file \"%s\" : %s",
		    remote_path, fx2txt(status));
		do_close(conn, handle, handle_len);
	} else if (write_error) {
		error("Couldn't write to \"%s\": %s", local_path,
		    strerror(write_errno));
		status = -1;
		do_close(conn, handle, handle_len);
	} else {
		status = do_close(conn, handle, handle_len);

		/* Override umask and utimes if asked */
#ifdef HAVE_FCHMOD
		if (pflag && fchmod(local_fd, mode) == -1)
#else 
		if (pflag && chmod(local_path, mode) == -1)
#endif /* HAVE_FCHMOD */
			error("Couldn't set mode on \"%s\": %s", local_path,
			      strerror(errno));
		if (pflag && (a->flags & SSH2_FILEXFER_ATTR_ACMODTIME)) {
			struct timeval tv[2];
			tv[0].tv_sec = a->atime;
			tv[1].tv_sec = a->mtime;
			tv[0].tv_usec = tv[1].tv_usec = 0;
			if (utimes(local_path, tv) == -1)
				error("Can't set times on \"%s\": %s",
				      local_path, strerror(errno));
		}
	}
	close(local_fd);
	buffer_free(&msg);
	xfree(handle);

	return(status);
}

int
do_upload(struct sftp_conn *conn, char *local_path, char *remote_path,
    int pflag)
{
	int local_fd, status;
	u_int handle_len, id, type;
	u_int64_t offset;
	char *handle, *data;
	Buffer msg;
	struct stat sb;
	Attrib a;
	u_int32_t startid;
	u_int32_t ackid;
	struct outstanding_ack {
		u_int id;
		u_int len;
		u_int64_t offset;
		TAILQ_ENTRY(outstanding_ack) tq;
	};
	TAILQ_HEAD(ackhead, outstanding_ack) acks;
	struct outstanding_ack *ack;

	TAILQ_INIT(&acks);

	if ((local_fd = open(local_path, O_RDONLY, 0)) == -1) {
		error("Couldn't open local file \"%s\" for reading: %s",
		    local_path, strerror(errno));
		return(-1);
	}
	if (fstat(local_fd, &sb) == -1) {
		error("Couldn't fstat local file \"%s\": %s",
		    local_path, strerror(errno));
		close(local_fd);
		return(-1);
	}
	stat_to_attrib(&sb, &a);

	a.flags &= ~SSH2_FILEXFER_ATTR_SIZE;
	a.flags &= ~SSH2_FILEXFER_ATTR_UIDGID;
	a.perm &= 0777;
	if (!pflag)
		a.flags &= ~SSH2_FILEXFER_ATTR_ACMODTIME;

	buffer_init(&msg);

	/* Send open request */
	id = conn->msg_id++;
	buffer_put_char(&msg, SSH2_FXP_OPEN);
	buffer_put_int(&msg, id);
	buffer_put_cstring(&msg, remote_path);
	buffer_put_int(&msg, SSH2_FXF_WRITE|SSH2_FXF_CREAT|SSH2_FXF_TRUNC);
	encode_attrib(&msg, &a);
	send_msg(conn->fd_out, &msg);
	debug3("Sent message SSH2_FXP_OPEN I:%d P:%s", id, remote_path);

	buffer_clear(&msg);

	handle = get_handle(conn->fd_in, id, &handle_len);
	if (handle == NULL) {
		close(local_fd);
		buffer_free(&msg);
		return(-1);
	}

	startid = ackid = id + 1;
	data = xmalloc(conn->transfer_buflen);

	/* Read from local and write to remote */
	offset = 0;
	for (;;) {
		int len;

		/*
		 * Can't use atomicio here because it returns 0 on EOF, thus losing
		 * the last block of the file
		 */
		do
			len = read(local_fd, data, conn->transfer_buflen);
		while ((len == -1) && (errno == EINTR || errno == EAGAIN));

		if (len == -1)
			fatal("Couldn't read from \"%s\": %s", local_path,
			    strerror(errno));

		if (len != 0) {
			ack = xmalloc(sizeof(*ack));
			ack->id = ++id;
			ack->offset = offset;
			ack->len = len;
			TAILQ_INSERT_TAIL(&acks, ack, tq);

			buffer_clear(&msg);
			buffer_put_char(&msg, SSH2_FXP_WRITE);
			buffer_put_int(&msg, ack->id);
			buffer_put_string(&msg, handle, handle_len);
			buffer_put_int64(&msg, offset);
			buffer_put_string(&msg, data, len);
			send_msg(conn->fd_out, &msg);
			debug3("Sent message SSH2_FXP_WRITE I:%d O:%llu S:%u",
			       id, (unsigned long long)offset, len);
		} else if (TAILQ_FIRST(&acks) == NULL)
			break;

		if (ack == NULL)
			fatal("Unexpected ACK %u", id);

		if (id == startid || len == 0 ||
		    id - ackid >= conn->num_requests) {
			u_int r_id;

			buffer_clear(&msg);
			get_msg(conn->fd_in, &msg);
			type = buffer_get_char(&msg);
			r_id = buffer_get_int(&msg);

			if (type != SSH2_FXP_STATUS)
				fatal("Expected SSH2_FXP_STATUS(%d) packet, "
				    "got %d", SSH2_FXP_STATUS, type);

			status = buffer_get_int(&msg);
			debug3("SSH2_FXP_STATUS %d", status);

			/* Find the request in our queue */
			for(ack = TAILQ_FIRST(&acks);
			    ack != NULL && ack->id != r_id;
			    ack = TAILQ_NEXT(ack, tq))
				;
			if (ack == NULL)
				fatal("Can't find request for ID %d", r_id);
			TAILQ_REMOVE(&acks, ack, tq);

			if (status != SSH2_FX_OK) {
				error("Couldn't write to remote file \"%s\": %s",
				      remote_path, fx2txt(status));
				do_close(conn, handle, handle_len);
				close(local_fd);
				goto done;
			}
			debug3("In write loop, ack for %u %d bytes at %llu",
			   ack->id, ack->len, (unsigned long long)ack->offset);
			++ackid;
			free(ack);
		}
		offset += len;
	}
	xfree(data);

	if (close(local_fd) == -1) {
		error("Couldn't close local file \"%s\": %s", local_path,
		    strerror(errno));
		do_close(conn, handle, handle_len);
		status = -1;
		goto done;
	}

	/* Override umask and utimes if asked */
	if (pflag)
		do_fsetstat(conn, handle, handle_len, &a);

	status = do_close(conn, handle, handle_len);

done:
	xfree(handle);
	buffer_free(&msg);
	return(status);
}