diff options
Diffstat (limited to 'ssh/sftpserver.c')
| -rw-r--r-- | ssh/sftpserver.c | 279 |
1 files changed, 279 insertions, 0 deletions
diff --git a/ssh/sftpserver.c b/ssh/sftpserver.c new file mode 100644 index 00000000..ba216872 --- /dev/null +++ b/ssh/sftpserver.c @@ -0,0 +1,279 @@ +/* + * 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, +}; |