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/*
* Implement the centralised parts of the server side of SFTP.
*/
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include "putty.h"
#include "ssh.h"
#include "sftp.h"
struct sftp_packet *sftp_handle_request(
SftpServer *srv, struct sftp_packet *req)
{
struct sftp_packet *reply;
unsigned id;
uint32_t flags;
ptrlen path, dstpath, handle, data;
uint64_t offset;
unsigned length;
struct fxp_attrs attrs;
DefaultSftpReplyBuilder dsrb;
SftpReplyBuilder *rb;
if (req->type == SSH_FXP_INIT) {
/*
* Special case which doesn't have a request id at the start.
*/
reply = sftp_pkt_init(SSH_FXP_VERSION);
/*
* Since we support only the lowest protocol version, we don't
* need to take the min of this and the client's version, or
* even to bother reading the client version number out of the
* input packet.
*/
put_uint32(reply, SFTP_PROTO_VERSION);
return reply;
}
/*
* Centralise the request id handling. We'll overwrite the type
* code of the output packet later.
*/
id = get_uint32(req);
reply = sftp_pkt_init(0);
put_uint32(reply, id);
dsrb.rb.vt = &DefaultSftpReplyBuilder_vt;
dsrb.pkt = reply;
rb = &dsrb.rb;
switch (req->type) {
case SSH_FXP_REALPATH:
path = get_string(req);
if (get_err(req))
goto decode_error;
sftpsrv_realpath(srv, rb, path);
break;
case SSH_FXP_OPEN:
path = get_string(req);
flags = get_uint32(req);
get_fxp_attrs(req, &attrs);
if (get_err(req))
goto decode_error;
if ((flags & (SSH_FXF_READ|SSH_FXF_WRITE)) == 0) {
fxp_reply_error(rb, SSH_FX_BAD_MESSAGE,
"open without READ or WRITE flag");
} else if ((flags & (SSH_FXF_CREAT|SSH_FXF_TRUNC)) == SSH_FXF_TRUNC) {
fxp_reply_error(rb, SSH_FX_BAD_MESSAGE,
"open with TRUNC but not CREAT");
} else if ((flags & (SSH_FXF_CREAT|SSH_FXF_EXCL)) == SSH_FXF_EXCL) {
fxp_reply_error(rb, SSH_FX_BAD_MESSAGE,
"open with EXCL but not CREAT");
} else {
sftpsrv_open(srv, rb, path, flags, attrs);
}
break;
case SSH_FXP_OPENDIR:
path = get_string(req);
if (get_err(req))
goto decode_error;
sftpsrv_opendir(srv, rb, path);
break;
case SSH_FXP_CLOSE:
handle = get_string(req);
if (get_err(req))
goto decode_error;
sftpsrv_close(srv, rb, handle);
break;
case SSH_FXP_MKDIR:
path = get_string(req);
get_fxp_attrs(req, &attrs);
if (get_err(req))
goto decode_error;
sftpsrv_mkdir(srv, rb, path, attrs);
break;
case SSH_FXP_RMDIR:
path = get_string(req);
if (get_err(req))
goto decode_error;
sftpsrv_rmdir(srv, rb, path);
break;
case SSH_FXP_REMOVE:
path = get_string(req);
if (get_err(req))
goto decode_error;
sftpsrv_remove(srv, rb, path);
break;
case SSH_FXP_RENAME:
path = get_string(req);
dstpath = get_string(req);
if (get_err(req))
goto decode_error;
sftpsrv_rename(srv, rb, path, dstpath);
break;
case SSH_FXP_STAT:
path = get_string(req);
if (get_err(req))
goto decode_error;
sftpsrv_stat(srv, rb, path, true);
break;
case SSH_FXP_LSTAT:
path = get_string(req);
if (get_err(req))
goto decode_error;
sftpsrv_stat(srv, rb, path, false);
break;
case SSH_FXP_FSTAT:
handle = get_string(req);
if (get_err(req))
goto decode_error;
sftpsrv_fstat(srv, rb, handle);
break;
case SSH_FXP_SETSTAT:
path = get_string(req);
get_fxp_attrs(req, &attrs);
if (get_err(req))
goto decode_error;
sftpsrv_setstat(srv, rb, path, attrs);
break;
case SSH_FXP_FSETSTAT:
handle = get_string(req);
get_fxp_attrs(req, &attrs);
if (get_err(req))
goto decode_error;
sftpsrv_fsetstat(srv, rb, handle, attrs);
break;
case SSH_FXP_READ:
handle = get_string(req);
offset = get_uint64(req);
length = get_uint32(req);
if (get_err(req))
goto decode_error;
sftpsrv_read(srv, rb, handle, offset, length);
break;
case SSH_FXP_READDIR:
handle = get_string(req);
if (get_err(req))
goto decode_error;
sftpsrv_readdir(srv, rb, handle, INT_MAX, false);
break;
case SSH_FXP_WRITE:
handle = get_string(req);
offset = get_uint64(req);
data = get_string(req);
if (get_err(req))
goto decode_error;
sftpsrv_write(srv, rb, handle, offset, data);
break;
default:
if (get_err(req))
goto decode_error;
fxp_reply_error(rb, SSH_FX_OP_UNSUPPORTED,
"Unrecognised request type");
break;
decode_error:
fxp_reply_error(rb, SSH_FX_BAD_MESSAGE, "Unable to decode request");
}
return reply;
}
static void default_reply_ok(SftpReplyBuilder *reply)
{
DefaultSftpReplyBuilder *d =
container_of(reply, DefaultSftpReplyBuilder, rb);
d->pkt->type = SSH_FXP_STATUS;
put_uint32(d->pkt, SSH_FX_OK);
put_stringz(d->pkt, "");
}
static void default_reply_error(
SftpReplyBuilder *reply, unsigned code, const char *msg)
{
DefaultSftpReplyBuilder *d =
container_of(reply, DefaultSftpReplyBuilder, rb);
d->pkt->type = SSH_FXP_STATUS;
put_uint32(d->pkt, code);
put_stringz(d->pkt, msg);
}
static void default_reply_name_count(SftpReplyBuilder *reply, unsigned count)
{
DefaultSftpReplyBuilder *d =
container_of(reply, DefaultSftpReplyBuilder, rb);
d->pkt->type = SSH_FXP_NAME;
put_uint32(d->pkt, count);
}
static void default_reply_full_name(SftpReplyBuilder *reply, ptrlen name,
ptrlen longname, struct fxp_attrs attrs)
{
DefaultSftpReplyBuilder *d =
container_of(reply, DefaultSftpReplyBuilder, rb);
d->pkt->type = SSH_FXP_NAME;
put_stringpl(d->pkt, name);
put_stringpl(d->pkt, longname);
put_fxp_attrs(d->pkt, attrs);
}
static void default_reply_simple_name(SftpReplyBuilder *reply, ptrlen name)
{
fxp_reply_name_count(reply, 1);
fxp_reply_full_name(reply, name, PTRLEN_LITERAL(""), no_attrs);
}
static void default_reply_handle(SftpReplyBuilder *reply, ptrlen handle)
{
DefaultSftpReplyBuilder *d =
container_of(reply, DefaultSftpReplyBuilder, rb);
d->pkt->type = SSH_FXP_HANDLE;
put_stringpl(d->pkt, handle);
}
static void default_reply_data(SftpReplyBuilder *reply, ptrlen data)
{
DefaultSftpReplyBuilder *d =
container_of(reply, DefaultSftpReplyBuilder, rb);
d->pkt->type = SSH_FXP_DATA;
put_stringpl(d->pkt, data);
}
static void default_reply_attrs(
SftpReplyBuilder *reply, struct fxp_attrs attrs)
{
DefaultSftpReplyBuilder *d =
container_of(reply, DefaultSftpReplyBuilder, rb);
d->pkt->type = SSH_FXP_ATTRS;
put_fxp_attrs(d->pkt, attrs);
}
const SftpReplyBuilderVtable DefaultSftpReplyBuilder_vt = {
.reply_ok = default_reply_ok,
.reply_error = default_reply_error,
.reply_simple_name = default_reply_simple_name,
.reply_name_count = default_reply_name_count,
.reply_full_name = default_reply_full_name,
.reply_handle = default_reply_handle,
.reply_data = default_reply_data,
.reply_attrs = default_reply_attrs,
};
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