/* * Copyright 2016 Jakub Klama * All rights reserved * * Redistribution and use in source and binary forms, with or without * modification, are permitted providing 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 #include #include #include #include #include #ifdef __illumos__ #include #endif #if defined(__FreeBSD__) #include #else #include "sbuf/sbuf.h" #endif #include "lib9p.h" #include "lib9p_impl.h" #include "fcall.h" #include "fid.h" #include "hashtable.h" #include "log.h" #include "linux_errno.h" #include "backend/backend.h" #include "threadpool.h" #define N(x) (sizeof(x) / sizeof(x[0])) static int l9p_dispatch_tversion(struct l9p_request *req); static int l9p_dispatch_tattach(struct l9p_request *req); static int l9p_dispatch_tclunk(struct l9p_request *req); static int l9p_dispatch_tcreate(struct l9p_request *req); static int l9p_dispatch_topen(struct l9p_request *req); static int l9p_dispatch_tread(struct l9p_request *req); static int l9p_dispatch_tremove(struct l9p_request *req); static int l9p_dispatch_tstat(struct l9p_request *req); static int l9p_dispatch_twalk(struct l9p_request *req); static int l9p_dispatch_twrite(struct l9p_request *req); static int l9p_dispatch_twstat(struct l9p_request *req); static int l9p_dispatch_tstatfs(struct l9p_request *req); static int l9p_dispatch_tlopen(struct l9p_request *req); static int l9p_dispatch_tlcreate(struct l9p_request *req); static int l9p_dispatch_tsymlink(struct l9p_request *req); static int l9p_dispatch_tmknod(struct l9p_request *req); static int l9p_dispatch_trename(struct l9p_request *req); static int l9p_dispatch_treadlink(struct l9p_request *req); static int l9p_dispatch_tgetattr(struct l9p_request *req); static int l9p_dispatch_tsetattr(struct l9p_request *req); static int l9p_dispatch_txattrwalk(struct l9p_request *req); static int l9p_dispatch_txattrcreate(struct l9p_request *req); static int l9p_dispatch_treaddir(struct l9p_request *req); static int l9p_dispatch_tfsync(struct l9p_request *req); static int l9p_dispatch_tlock(struct l9p_request *req); static int l9p_dispatch_tgetlock(struct l9p_request *req); static int l9p_dispatch_tlink(struct l9p_request *req); static int l9p_dispatch_tmkdir(struct l9p_request *req); static int l9p_dispatch_trenameat(struct l9p_request *req); static int l9p_dispatch_tunlinkat(struct l9p_request *req); /* * Each Txxx handler has a "must run" flag. If it is false, * we check for a flush request before calling the handler. * If a flush is already requested we can instantly fail the * request with EINTR. * * Tclunk and Tremove must run because they make their fids * become invalid. Tversion and Tattach should never get * a flush request applied (it makes no sense as the connection * is not really running yet), so it should be harmless to * set them either way, but for now we have them as must-run. * Flushing a Tflush is not really allowed either so we keep * these as must-run too (although they run without being done * threaded anyway). */ struct l9p_handler { enum l9p_ftype type; int (*handler)(struct l9p_request *); bool must_run; }; static const struct l9p_handler l9p_handlers_no_version[] = { {L9P_TVERSION, l9p_dispatch_tversion, true}, }; static const struct l9p_handler l9p_handlers_base[] = { {L9P_TVERSION, l9p_dispatch_tversion, true}, {L9P_TATTACH, l9p_dispatch_tattach, true}, {L9P_TCLUNK, l9p_dispatch_tclunk, true}, {L9P_TFLUSH, l9p_threadpool_tflush, true}, {L9P_TCREATE, l9p_dispatch_tcreate, false}, {L9P_TOPEN, l9p_dispatch_topen, false}, {L9P_TREAD, l9p_dispatch_tread, false}, {L9P_TWRITE, l9p_dispatch_twrite, false}, {L9P_TREMOVE, l9p_dispatch_tremove, true}, {L9P_TSTAT, l9p_dispatch_tstat, false}, {L9P_TWALK, l9p_dispatch_twalk, false}, {L9P_TWSTAT, l9p_dispatch_twstat, false} }; static const struct l9p_handler l9p_handlers_dotu[] = { {L9P_TVERSION, l9p_dispatch_tversion, true}, {L9P_TATTACH, l9p_dispatch_tattach, true}, {L9P_TCLUNK, l9p_dispatch_tclunk, true}, {L9P_TFLUSH, l9p_threadpool_tflush, true}, {L9P_TCREATE, l9p_dispatch_tcreate, false}, {L9P_TOPEN, l9p_dispatch_topen, false}, {L9P_TREAD, l9p_dispatch_tread, false}, {L9P_TWRITE, l9p_dispatch_twrite, false}, {L9P_TREMOVE, l9p_dispatch_tremove, true}, {L9P_TSTAT, l9p_dispatch_tstat, false}, {L9P_TWALK, l9p_dispatch_twalk, false}, {L9P_TWSTAT, l9p_dispatch_twstat, false} }; static const struct l9p_handler l9p_handlers_dotL[] = { {L9P_TVERSION, l9p_dispatch_tversion, true}, {L9P_TATTACH, l9p_dispatch_tattach, true}, {L9P_TCLUNK, l9p_dispatch_tclunk, true}, {L9P_TFLUSH, l9p_threadpool_tflush, true}, {L9P_TCREATE, l9p_dispatch_tcreate, false}, {L9P_TOPEN, l9p_dispatch_topen, false}, {L9P_TREAD, l9p_dispatch_tread, false}, {L9P_TWRITE, l9p_dispatch_twrite, false}, {L9P_TREMOVE, l9p_dispatch_tremove, true}, {L9P_TSTAT, l9p_dispatch_tstat, false}, {L9P_TWALK, l9p_dispatch_twalk, false}, {L9P_TWSTAT, l9p_dispatch_twstat, false}, {L9P_TSTATFS, l9p_dispatch_tstatfs, false}, {L9P_TLOPEN, l9p_dispatch_tlopen, false}, {L9P_TLCREATE, l9p_dispatch_tlcreate, false}, {L9P_TSYMLINK, l9p_dispatch_tsymlink, false}, {L9P_TMKNOD, l9p_dispatch_tmknod, false}, {L9P_TRENAME, l9p_dispatch_trename, false}, {L9P_TREADLINK, l9p_dispatch_treadlink, false}, {L9P_TGETATTR, l9p_dispatch_tgetattr, false}, {L9P_TSETATTR, l9p_dispatch_tsetattr, false}, {L9P_TXATTRWALK, l9p_dispatch_txattrwalk, false}, {L9P_TXATTRCREATE, l9p_dispatch_txattrcreate, false}, {L9P_TREADDIR, l9p_dispatch_treaddir, false}, {L9P_TFSYNC, l9p_dispatch_tfsync, false}, {L9P_TLOCK, l9p_dispatch_tlock, true}, {L9P_TGETLOCK, l9p_dispatch_tgetlock, true}, {L9P_TLINK, l9p_dispatch_tlink, false}, {L9P_TMKDIR, l9p_dispatch_tmkdir, false}, {L9P_TRENAMEAT, l9p_dispatch_trenameat, false}, {L9P_TUNLINKAT, l9p_dispatch_tunlinkat, false}, }; /* * NB: version index 0 is reserved for new connections, and * is a protocol that handles only L9P_TVERSION. Once we get a * valid version, we start a new session using its dispatch table. */ static const struct { const char *name; const struct l9p_handler *handlers; int n_handlers; } l9p_versions[] = { { "", l9p_handlers_no_version, N(l9p_handlers_no_version) }, { "9P2000", l9p_handlers_base, N(l9p_handlers_base) }, { "9P2000.u", l9p_handlers_dotu, N(l9p_handlers_dotu), }, { "9P2000.L", l9p_handlers_dotL, N(l9p_handlers_dotL), }, }; /* * Run the appropriate handler for this request. * It's our caller's responsibility to respond. */ int l9p_dispatch_request(struct l9p_request *req) { struct l9p_connection *conn; #if defined(L9P_DEBUG) struct sbuf *sb; #endif size_t i, n; const struct l9p_handler *handlers, *hp; bool flush_requested; conn = req->lr_conn; flush_requested = req->lr_flushstate == L9P_FLUSH_REQUESTED_PRE_START; handlers = l9p_versions[conn->lc_version].handlers; n = (size_t)l9p_versions[conn->lc_version].n_handlers; for (hp = handlers, i = 0; i < n; hp++, i++) if (req->lr_req.hdr.type == hp->type) goto found; hp = NULL; found: #if defined(L9P_DEBUG) sb = sbuf_new_auto(); if (flush_requested) { sbuf_cat(sb, "FLUSH requested pre-dispatch"); if (hp != NULL && hp->must_run) sbuf_cat(sb, ", but must run"); sbuf_cat(sb, ": "); } l9p_describe_fcall(&req->lr_req, conn->lc_version, sb); sbuf_finish(sb); L9P_LOG(L9P_DEBUG, "%s", sbuf_data(sb)); sbuf_delete(sb); #endif if (hp != NULL) { if (!flush_requested || hp->must_run) return (hp->handler(req)); return (EINTR); } L9P_LOG(L9P_WARNING, "unknown request of type %d", req->lr_req.hdr.type); return (ENOSYS); } /* * Translate BSD errno to 9P2000/9P2000.u errno. */ static inline int e29p(int errnum) { static int const table[] = { [ENOTEMPTY] = EPERM, [EDQUOT] = EPERM, [ENOSYS] = EPERM, /* ??? */ }; if ((size_t)errnum < N(table) && table[errnum] != 0) return (table[errnum]); if (errnum <= ERANGE) return (errnum); return (EIO); /* ??? */ } /* * Translate BSD errno to Linux errno. */ static inline int e2linux(int errnum) { static int const table[] = { [EDEADLK] = LINUX_EDEADLK, [EAGAIN] = LINUX_EAGAIN, [EINPROGRESS] = LINUX_EINPROGRESS, [EALREADY] = LINUX_EALREADY, [ENOTSOCK] = LINUX_ENOTSOCK, [EDESTADDRREQ] = LINUX_EDESTADDRREQ, [EMSGSIZE] = LINUX_EMSGSIZE, [EPROTOTYPE] = LINUX_EPROTOTYPE, [ENOPROTOOPT] = LINUX_ENOPROTOOPT, [EPROTONOSUPPORT] = LINUX_EPROTONOSUPPORT, [ESOCKTNOSUPPORT] = LINUX_ESOCKTNOSUPPORT, [EOPNOTSUPP] = LINUX_EOPNOTSUPP, [EPFNOSUPPORT] = LINUX_EPFNOSUPPORT, [EAFNOSUPPORT] = LINUX_EAFNOSUPPORT, [EADDRINUSE] = LINUX_EADDRINUSE, [EADDRNOTAVAIL] = LINUX_EADDRNOTAVAIL, [ENETDOWN] = LINUX_ENETDOWN, [ENETUNREACH] = LINUX_ENETUNREACH, [ENETRESET] = LINUX_ENETRESET, [ECONNABORTED] = LINUX_ECONNABORTED, [ECONNRESET] = LINUX_ECONNRESET, [ENOBUFS] = LINUX_ENOBUFS, [EISCONN] = LINUX_EISCONN, [ENOTCONN] = LINUX_ENOTCONN, [ESHUTDOWN] = LINUX_ESHUTDOWN, [ETOOMANYREFS] = LINUX_ETOOMANYREFS, [ETIMEDOUT] = LINUX_ETIMEDOUT, [ECONNREFUSED] = LINUX_ECONNREFUSED, [ELOOP] = LINUX_ELOOP, [ENAMETOOLONG] = LINUX_ENAMETOOLONG, [EHOSTDOWN] = LINUX_EHOSTDOWN, [EHOSTUNREACH] = LINUX_EHOSTUNREACH, [ENOTEMPTY] = LINUX_ENOTEMPTY, #ifndef __illumos__ [EPROCLIM] = LINUX_EAGAIN, #endif [EUSERS] = LINUX_EUSERS, [EDQUOT] = LINUX_EDQUOT, [ESTALE] = LINUX_ESTALE, [EREMOTE] = LINUX_EREMOTE, /* EBADRPC = unmappable? */ /* ERPCMISMATCH = unmappable? */ /* EPROGUNAVAIL = unmappable? */ /* EPROGMISMATCH = unmappable? */ /* EPROCUNAVAIL = unmappable? */ [ENOLCK] = LINUX_ENOLCK, [ENOSYS] = LINUX_ENOSYS, /* EFTYPE = unmappable? */ /* EAUTH = unmappable? */ /* ENEEDAUTH = unmappable? */ [EIDRM] = LINUX_EIDRM, [ENOMSG] = LINUX_ENOMSG, [EOVERFLOW] = LINUX_EOVERFLOW, [ECANCELED] = LINUX_ECANCELED, [EILSEQ] = LINUX_EILSEQ, /* EDOOFUS = unmappable? */ [EBADMSG] = LINUX_EBADMSG, [EMULTIHOP] = LINUX_EMULTIHOP, [ENOLINK] = LINUX_ENOLINK, [EPROTO] = LINUX_EPROTO, /* ENOTCAPABLE = unmappable? */ #ifdef ECAPMODE [ECAPMODE] = EPERM, #endif #ifdef ENOTRECOVERABLE [ENOTRECOVERABLE] = LINUX_ENOTRECOVERABLE, #endif #ifdef EOWNERDEAD [EOWNERDEAD] = LINUX_EOWNERDEAD, #endif }; /* * In case we want to return a raw Linux errno, allow negative * values a la Linux kernel internals. * * Values up to ERANGE are shared across systems (see * linux_errno.h), except for EAGAIN. */ if (errnum < 0) return (-errnum); if ((size_t)errnum < N(table) && table[errnum] != 0) return (table[errnum]); if (errnum <= ERANGE) return (errnum); L9P_LOG(L9P_WARNING, "cannot map errno %d to anything reasonable", errnum); return (LINUX_ENOTRECOVERABLE); /* ??? */ } /* * Send response to request, or possibly just drop request. * We also need to know whether to remove the request from * the tag hash table. */ void l9p_respond(struct l9p_request *req, bool drop, bool rmtag) { struct l9p_connection *conn = req->lr_conn; size_t iosize; #if defined(L9P_DEBUG) struct sbuf *sb; const char *ftype; #endif int error; req->lr_resp.hdr.tag = req->lr_req.hdr.tag; error = req->lr_error; if (error == 0) req->lr_resp.hdr.type = req->lr_req.hdr.type + 1; else { if (conn->lc_version == L9P_2000L) { req->lr_resp.hdr.type = L9P_RLERROR; req->lr_resp.error.errnum = (uint32_t)e2linux(error); } else { req->lr_resp.hdr.type = L9P_RERROR; req->lr_resp.error.ename = strerror(error); req->lr_resp.error.errnum = (uint32_t)e29p(error); } } #if defined(L9P_DEBUG) sb = sbuf_new_auto(); l9p_describe_fcall(&req->lr_resp, conn->lc_version, sb); sbuf_finish(sb); switch (req->lr_flushstate) { case L9P_FLUSH_NONE: default: ftype = ""; break; case L9P_FLUSH_REQUESTED_PRE_START: ftype = "FLUSH requested pre-dispatch: "; break; case L9P_FLUSH_REQUESTED_POST_START: ftype = "FLUSH requested while running: "; break; case L9P_FLUSH_TOOLATE: ftype = "FLUSH requested too late: "; break; } L9P_LOG(L9P_DEBUG, "%s%s%s", drop ? "DROP: " : "", ftype, sbuf_data(sb)); sbuf_delete(sb); #endif error = drop ? 0 : l9p_pufcall(&req->lr_resp_msg, &req->lr_resp, conn->lc_version); if (rmtag) ht_remove(&conn->lc_requests, req->lr_req.hdr.tag); if (error != 0) { L9P_LOG(L9P_ERROR, "cannot pack response"); drop = true; } if (drop) { conn->lc_lt.lt_drop_response(req, req->lr_resp_msg.lm_iov, req->lr_resp_msg.lm_niov, conn->lc_lt.lt_aux); } else { iosize = req->lr_resp_msg.lm_size; /* * Include I/O size in calculation for Rread and * Rreaddir responses. */ if (req->lr_resp.hdr.type == L9P_RREAD || req->lr_resp.hdr.type == L9P_RREADDIR) iosize += req->lr_resp.io.count; conn->lc_lt.lt_send_response(req, req->lr_resp_msg.lm_iov, req->lr_resp_msg.lm_niov, iosize, conn->lc_lt.lt_aux); } l9p_freefcall(&req->lr_req); l9p_freefcall(&req->lr_resp); free(req); } /* * This allows a caller to iterate through the data in a * read or write request (creating the data if packing, * scanning through it if unpacking). This is used for * writing readdir entries, so mode should be L9P_PACK * (but we allow L9P_UNPACK so that debug code can also scan * through the data later, if desired). * * This relies on the Tread op having positioned the request's * iov to the beginning of the data buffer (note the l9p_seek_iov * in l9p_dispatch_tread). */ void l9p_init_msg(struct l9p_message *msg, struct l9p_request *req, enum l9p_pack_mode mode) { msg->lm_size = 0; msg->lm_mode = mode; msg->lm_cursor_iov = 0; msg->lm_cursor_offset = 0; msg->lm_niov = req->lr_data_niov; memcpy(msg->lm_iov, req->lr_data_iov, sizeof (struct iovec) * req->lr_data_niov); } enum fid_lookup_flags { F_REQUIRE_OPEN = 0x01, /* require that the file be marked OPEN */ F_REQUIRE_DIR = 0x02, /* require that the file be marked ISDIR */ F_REQUIRE_XATTR = 0x04, /* require that the file be marked XATTR */ F_REQUIRE_AUTH = 0x08, /* require that the fid be marked AUTH */ F_FORBID_OPEN = 0x10, /* forbid that the file be marked OPEN */ F_FORBID_DIR = 0x20, /* forbid that the file be marked ISDIR */ F_FORBID_XATTR = 0x40, /* forbid that the file be marked XATTR */ F_ALLOW_AUTH = 0x80, /* allow that the fid be marked AUTH */ }; /* * Look up a fid. It must correspond to a valid file, else we return * the given errno (some "not a valid fid" calls must return EIO and * some must return EINVAL and qemu returns ENOENT in other cases and * so on, so we just provide a general "return this error number"). * * Callers may also set constraints: fid must be (or not be) open, * must be (or not be) a directory, must be (or not be) an xattr. * * Only one op has a fid that *must* be an auth fid. Most ops forbid * auth fids So instead of FORBID we have ALLOW here and the default * is FORBID. */ static inline int fid_lookup(struct l9p_connection *conn, uint32_t fid, int err, int flags, struct l9p_fid **afile) { struct l9p_fid *file; file = ht_find(&conn->lc_files, fid); if (file == NULL) return (err); /* * As soon as we go multithreaded / async, this * assert has to become "return EINVAL" or "return err". * * We may also need a way to mark a fid as * "in async op" (valid for some purposes, but cannot be * used elsewhere until async op is completed or aborted). * * For now, this serves for bug-detecting. */ assert(l9p_fid_isvalid(file)); /* * Note that we're inline expanded and flags is constant, * so unnecessary tests just drop out entirely. */ if ((flags & F_REQUIRE_OPEN) && !l9p_fid_isopen(file)) return (EINVAL); if ((flags & F_FORBID_OPEN) && l9p_fid_isopen(file)) return (EINVAL); if ((flags & F_REQUIRE_DIR) && !l9p_fid_isdir(file)) return (ENOTDIR); if ((flags & F_FORBID_DIR) && l9p_fid_isdir(file)) return (EISDIR); if ((flags & F_REQUIRE_XATTR) && !l9p_fid_isxattr(file)) return (EINVAL); if ((flags & F_FORBID_XATTR) && l9p_fid_isxattr(file)) return (EINVAL); if (l9p_fid_isauth(file)) { if ((flags & (F_REQUIRE_AUTH | F_ALLOW_AUTH)) == 0) return (EINVAL); } else if (flags & F_REQUIRE_AUTH) return (EINVAL); *afile = file; return (0); } /* * Append variable-size stat object and adjust io count. * Returns 0 if the entire stat object was packed, -1 if not. * A fully packed object updates the request's io count. * * Caller must use their own private l9p_message object since * a partially packed object will leave the message object in * a useless state. * * Frees the stat object. */ int l9p_pack_stat(struct l9p_message *msg, struct l9p_request *req, struct l9p_stat *st) { struct l9p_connection *conn = req->lr_conn; uint16_t size = l9p_sizeof_stat(st, conn->lc_version); int ret = 0; assert(msg->lm_mode == L9P_PACK); if (req->lr_resp.io.count + size > req->lr_req.io.count || l9p_pustat(msg, st, conn->lc_version) < 0) ret = -1; else req->lr_resp.io.count += size; l9p_freestat(st); return (ret); } static int l9p_dispatch_tversion(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_server *server = conn->lc_server; enum l9p_version remote_version = L9P_INVALID_VERSION; size_t i; const char *remote_version_name; for (i = 0; i < N(l9p_versions); i++) { if (strcmp(req->lr_req.version.version, l9p_versions[i].name) == 0) { remote_version = (enum l9p_version)i; break; } } if (remote_version == L9P_INVALID_VERSION) { L9P_LOG(L9P_ERROR, "unsupported remote version: %s", req->lr_req.version.version); return (ENOSYS); } remote_version_name = l9p_versions[remote_version].name; L9P_LOG(L9P_INFO, "remote version: %s", remote_version_name); L9P_LOG(L9P_INFO, "local version: %s", l9p_versions[server->ls_max_version].name); conn->lc_version = MIN(remote_version, server->ls_max_version); conn->lc_msize = MIN(req->lr_req.version.msize, conn->lc_msize); conn->lc_max_io_size = conn->lc_msize - 24; req->lr_resp.version.version = strdup(remote_version_name); req->lr_resp.version.msize = conn->lc_msize; return (0); } static int l9p_dispatch_tattach(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; struct l9p_fid *fid; int error; /* * We still don't have Tauth yet, but let's code this part * anyway. * * Look up the auth fid first since if it fails we can just * return immediately. */ if (req->lr_req.tattach.afid != L9P_NOFID) { error = fid_lookup(conn, req->lr_req.tattach.afid, EINVAL, F_REQUIRE_AUTH, &req->lr_fid2); if (error) return (error); } else req->lr_fid2 = NULL; fid = l9p_connection_alloc_fid(conn, req->lr_req.hdr.fid); if (fid == NULL) return (EINVAL); be = conn->lc_server->ls_backend; req->lr_fid = fid; /* For backend convenience, set NONUNAME on 9P2000. */ if (conn->lc_version == L9P_2000) req->lr_req.tattach.n_uname = L9P_NONUNAME; error = be->attach(be->softc, req); /* * On success, fid becomes valid; on failure, disconnect. * It certainly *should* be a directory here... */ if (error == 0) { l9p_fid_setvalid(fid); if (req->lr_resp.rattach.qid.type & L9P_QTDIR) l9p_fid_setdir(fid); } else l9p_connection_remove_fid(conn, fid); return (error); } static int l9p_dispatch_tclunk(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; struct l9p_fid *fid; int error; /* Note that clunk is the only way to dispose of an auth fid. */ error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_ALLOW_AUTH, &fid); if (error) return (error); be = conn->lc_server->ls_backend; l9p_fid_unsetvalid(fid); /* * If it's an xattr fid there must, by definition, be an * xattrclunk. The xattrclunk function can only be NULL if * xattrwalk and xattrcreate are NULL or always return error. * * Q: do we want to allow async xattrclunk in case of very * large xattr create? This will make things difficult, * so probably not. */ if (l9p_fid_isxattr(fid)) error = be->xattrclunk(be->softc, fid); else error = be->clunk(be->softc, fid); /* fid is now gone regardless of any error return */ l9p_connection_remove_fid(conn, fid); return (error); } static int l9p_dispatch_tcreate(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; uint32_t dmperm; int error; /* Incoming fid must represent a directory that has not been opened. */ error = fid_lookup(conn, req->lr_req.hdr.fid, EINVAL, F_REQUIRE_DIR | F_FORBID_OPEN, &req->lr_fid); if (error) return (error); be = conn->lc_server->ls_backend; dmperm = req->lr_req.tcreate.perm; #define MKDIR_OR_SIMILAR \ (L9P_DMDIR | L9P_DMSYMLINK | L9P_DMNAMEDPIPE | L9P_DMSOCKET | L9P_DMDEVICE) /* * TODO: * - check new file name * - break out different kinds of create (file vs mkdir etc) * - add async file-create (leaves req->lr_fid in limbo) * * A successful file-create changes the fid into an open file. */ error = be->create(be->softc, req); if (error == 0 && (dmperm & MKDIR_OR_SIMILAR) == 0) { l9p_fid_unsetdir(req->lr_fid); l9p_fid_setopen(req->lr_fid); } return (error); } static int l9p_dispatch_topen(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_FORBID_OPEN | F_FORBID_XATTR, &req->lr_fid); if (error) return (error); be = conn->lc_server->ls_backend; /* * TODO: * - add async open (leaves req->lr_fid in limbo) */ error = be->open(be->softc, req); if (error == 0) l9p_fid_setopen(req->lr_fid); return (error); } static int l9p_dispatch_tread(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; struct l9p_fid *fid; int error; /* Xattr fids are not open, so we need our own tests. */ error = fid_lookup(conn, req->lr_req.hdr.fid, EINVAL, 0, &req->lr_fid); if (error) return (error); /* * Adjust so that writing messages (packing data) starts * right after the count field in the response. * * size[4] + Rread[1] + tag[2] + count[4] = 11 */ l9p_seek_iov(req->lr_resp_msg.lm_iov, req->lr_resp_msg.lm_niov, req->lr_data_iov, &req->lr_data_niov, 11); /* * If it's an xattr fid there must, by definition, be an * xattrread. The xattrread function can only be NULL if * xattrwalk and xattrcreate are NULL or always return error. * * TODO: * separate out directory-read * allow async read */ be = conn->lc_server->ls_backend; fid = req->lr_fid; if (l9p_fid_isxattr(fid)) { error = be->xattrread(be->softc, req); } else if (l9p_fid_isopen(fid)) { error = be->read(be->softc, req); } else { error = EINVAL; } return (error); } static int l9p_dispatch_tremove(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; struct l9p_fid *fid; int error; /* * ?? Should we allow Tremove on auth fids? If so, do * we pretend it is just a Tclunk? */ error = fid_lookup(conn, req->lr_req.hdr.fid, EINVAL, 0, &fid); if (error) return (error); be = conn->lc_server->ls_backend; l9p_fid_unsetvalid(fid); error = be->remove(be->softc, fid); /* fid is now gone regardless of any error return */ l9p_connection_remove_fid(conn, fid); return (error); } static int l9p_dispatch_tstat(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; struct l9p_fid *fid; int error; /* Allow Tstat on auth fid? Seems harmless enough... */ error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_ALLOW_AUTH, &fid); if (error) return (error); be = conn->lc_server->ls_backend; req->lr_fid = fid; error = be->stat(be->softc, req); if (error == 0) { if (l9p_fid_isauth(fid)) req->lr_resp.rstat.stat.qid.type |= L9P_QTAUTH; /* should we check req->lr_resp.rstat.qid.type L9P_QTDIR bit? */ if (req->lr_resp.rstat.stat.qid.type &= L9P_QTDIR) l9p_fid_setdir(fid); else l9p_fid_unsetdir(fid); } return (error); } static int l9p_dispatch_twalk(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; struct l9p_fid *fid, *newfid; uint16_t n; int error; /* Can forbid XATTR, but cannot require DIR. */ error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_FORBID_XATTR, &fid); if (error) return (error); if (req->lr_req.twalk.hdr.fid != req->lr_req.twalk.newfid) { newfid = l9p_connection_alloc_fid(conn, req->lr_req.twalk.newfid); if (newfid == NULL) return (EINVAL); } else newfid = fid; be = conn->lc_server->ls_backend; req->lr_fid = fid; req->lr_newfid = newfid; error = be->walk(be->softc, req); /* * If newfid == fid, then fid itself has (potentially) changed, * but is still valid. Otherwise set newfid valid on * success, and destroy it on error. */ if (newfid != fid) { if (error == 0) l9p_fid_setvalid(newfid); else l9p_connection_remove_fid(conn, newfid); } /* * If we walked any name elements, the last (n-1'th) qid * has the type (dir vs file) for the new fid. Otherwise * the type of newfid is the same as fid. Of course, if * n==0 and fid==newfid, fid is already set up correctly * as the whole thing was a big no-op, but it's safe to * copy its dir bit to itself. */ if (error == 0) { n = req->lr_resp.rwalk.nwqid; if (n > 0) { if (req->lr_resp.rwalk.wqid[n - 1].type & L9P_QTDIR) l9p_fid_setdir(newfid); } else { if (l9p_fid_isdir(fid)) l9p_fid_setdir(newfid); } } return (error); } static int l9p_dispatch_twrite(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; struct l9p_fid *fid; int error; /* Cannot require open due to xattr write, but can forbid dir. */ error = fid_lookup(conn, req->lr_req.hdr.fid, EINVAL, F_FORBID_DIR, &req->lr_fid); if (error) return (error); /* * Adjust to point to the data to be written (a la * l9p_dispatch_tread, but we're pointing into the request * buffer rather than the response): * * size[4] + Twrite[1] + tag[2] + fid[4] + offset[8] + count[4] = 23 */ l9p_seek_iov(req->lr_req_msg.lm_iov, req->lr_req_msg.lm_niov, req->lr_data_iov, &req->lr_data_niov, 23); /* * Unlike read, write and xattrwrite are optional (for R/O fs). * * TODO: * allow async write */ be = conn->lc_server->ls_backend; fid = req->lr_fid; if (l9p_fid_isxattr(fid)) { error = be->xattrwrite != NULL ? be->xattrwrite(be->softc, req) : ENOSYS; } else if (l9p_fid_isopen(fid)) { error = be->write != NULL ? be->write(be->softc, req) : ENOSYS; } else { error = EINVAL; } return (error); } static int l9p_dispatch_twstat(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; error = fid_lookup(conn, req->lr_req.hdr.fid, EINVAL, F_FORBID_XATTR, &req->lr_fid); if (error) return (error); be = conn->lc_server->ls_backend; error = be->wstat != NULL ? be->wstat(be->softc, req) : ENOSYS; return (error); } static int l9p_dispatch_tstatfs(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; /* Should we allow statfs on auth fids? */ error = fid_lookup(conn, req->lr_req.hdr.fid, EINVAL, 0, &req->lr_fid); if (error) return (error); be = conn->lc_server->ls_backend; error = be->statfs(be->softc, req); return (error); } static int l9p_dispatch_tlopen(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_FORBID_OPEN | F_FORBID_XATTR, &req->lr_fid); if (error) return (error); be = conn->lc_server->ls_backend; /* * TODO: * - add async open (leaves req->lr_fid in limbo) */ error = be->lopen != NULL ? be->lopen(be->softc, req) : ENOSYS; if (error == 0) l9p_fid_setopen(req->lr_fid); return (error); } static int l9p_dispatch_tlcreate(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_REQUIRE_DIR | F_FORBID_OPEN, &req->lr_fid); if (error) return (error); be = conn->lc_server->ls_backend; /* * TODO: * - check new file name * - add async create (leaves req->lr_fid in limbo) */ error = be->lcreate != NULL ? be->lcreate(be->softc, req) : ENOSYS; if (error == 0) { l9p_fid_unsetdir(req->lr_fid); l9p_fid_setopen(req->lr_fid); } return (error); } static int l9p_dispatch_tsymlink(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; /* This doesn't affect the containing dir; maybe allow OPEN? */ error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_REQUIRE_DIR | F_FORBID_OPEN, &req->lr_fid); if (error) return (error); be = conn->lc_server->ls_backend; /* * TODO: * - check new file name */ error = be->symlink != NULL ? be->symlink(be->softc, req) : ENOSYS; return (error); } static int l9p_dispatch_tmknod(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; /* This doesn't affect the containing dir; maybe allow OPEN? */ error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_REQUIRE_DIR | F_FORBID_OPEN, &req->lr_fid); if (error) return (error); be = conn->lc_server->ls_backend; /* * TODO: * - check new file name */ error = be->mknod != NULL ? be->mknod(be->softc, req) : ENOSYS; return (error); } static int l9p_dispatch_trename(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; /* Rename directory or file (including symlink etc). */ error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_FORBID_XATTR, &req->lr_fid); if (error) return (error); /* Doesn't affect new dir fid; maybe allow OPEN? */ error = fid_lookup(conn, req->lr_req.trename.dfid, ENOENT, F_REQUIRE_DIR | F_FORBID_OPEN, &req->lr_fid2); if (error) return (error); be = conn->lc_server->ls_backend; /* * TODO: * - check new file name (trename.name) */ error = be->rename != NULL ? be->rename(be->softc, req) : ENOSYS; return (error); } static int l9p_dispatch_treadlink(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; /* * The underlying readlink will fail unless it's a symlink, * and the back end has to check, but we might as well forbid * directories and open files here since it's cheap. */ error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_FORBID_DIR | F_FORBID_OPEN, &req->lr_fid); if (error) return (error); be = conn->lc_server->ls_backend; error = be->readlink != NULL ? be->readlink(be->softc, req) : ENOSYS; return (error); } static int l9p_dispatch_tgetattr(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_FORBID_XATTR, &req->lr_fid); if (error) return (error); be = conn->lc_server->ls_backend; error = be->getattr != NULL ? be->getattr(be->softc, req) : ENOSYS; return (error); } static int l9p_dispatch_tsetattr(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_FORBID_XATTR, &req->lr_fid); if (error) return (error); be = conn->lc_server->ls_backend; error = be->setattr != NULL ? be->setattr(be->softc, req) : ENOSYS; return (error); } static int l9p_dispatch_txattrwalk(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; struct l9p_fid *fid, *newfid; int error; /* * Not sure if we care if file-or-dir is open or not. * However, the fid argument should always be a file or * dir and the newfid argument must be supplied, must * be different, and always becomes a new xattr, * so this is not very much like Twalk. */ error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_FORBID_XATTR, &fid); if (error) return (error); newfid = l9p_connection_alloc_fid(conn, req->lr_req.txattrwalk.newfid); if (newfid == NULL) return (EINVAL); be = conn->lc_server->ls_backend; req->lr_fid = fid; req->lr_newfid = newfid; error = be->xattrwalk != NULL ? be->xattrwalk(be->softc, req) : ENOSYS; /* * Success/fail is similar to Twalk, except that we need * to set the xattr type bit in the new fid. It's also * much simpler since newfid is always a new fid. */ if (error == 0) { l9p_fid_setvalid(newfid); l9p_fid_setxattr(newfid); } else { l9p_connection_remove_fid(conn, newfid); } return (error); } static int l9p_dispatch_txattrcreate(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; struct l9p_fid *fid; int error; /* * Forbid incoming open fid since it's going to become an * xattr fid instead. If it turns out we need to allow * it, fs code will need to handle this. * * Curiously, qemu 9pfs uses ENOENT for a bad txattrwalk * fid, but EINVAL for txattrcreate (so we do too). */ error = fid_lookup(conn, req->lr_req.hdr.fid, EINVAL, F_FORBID_XATTR | F_FORBID_OPEN, &fid); if (error) return (error); be = conn->lc_server->ls_backend; req->lr_fid = fid; error = be->xattrcreate != NULL ? be->xattrcreate(be->softc, req) : ENOSYS; /* * On success, fid has changed from a regular (file or dir) * fid to an xattr fid. */ if (error == 0) { l9p_fid_unsetdir(fid); l9p_fid_setxattr(fid); } return (error); } static int l9p_dispatch_treaddir(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_REQUIRE_DIR | F_REQUIRE_OPEN, &req->lr_fid); if (error) return (error); /* * Adjust so that writing messages (packing data) starts * right after the count field in the response. * * size[4] + Rreaddir[1] + tag[2] + count[4] = 11 */ l9p_seek_iov(req->lr_resp_msg.lm_iov, req->lr_resp_msg.lm_niov, req->lr_data_iov, &req->lr_data_niov, 11); be = conn->lc_server->ls_backend; error = be->readdir != NULL ? be->readdir(be->softc, req) : ENOSYS; return (error); } static int l9p_dispatch_tfsync(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_REQUIRE_OPEN, &req->lr_fid); if (error) return (error); be = conn->lc_server->ls_backend; error = be->fsync != NULL ? be->fsync(be->softc, req) : ENOSYS; return (error); } static int l9p_dispatch_tlock(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; /* Forbid directories? */ error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_REQUIRE_OPEN, &req->lr_fid); if (error) return (error); be = conn->lc_server->ls_backend; /* * TODO: multiple client handling; perhaps async locking. */ error = be->lock != NULL ? be->lock(be->softc, req) : ENOSYS; return (error); } static int l9p_dispatch_tgetlock(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_REQUIRE_OPEN, &req->lr_fid); if (error) return (error); be = conn->lc_server->ls_backend; /* * TODO: multiple client handling; perhaps async locking. */ error = be->getlock != NULL ? be->getlock(be->softc, req) : ENOSYS; return (error); } static int l9p_dispatch_tlink(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; /* * Note, dfid goes into fid2 in current scheme. * * Allow open dir? Target dir fid is not modified... */ error = fid_lookup(conn, req->lr_req.tlink.dfid, ENOENT, F_REQUIRE_DIR | F_FORBID_OPEN, &req->lr_fid2); if (error) return (error); error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_FORBID_DIR | F_FORBID_XATTR, &req->lr_fid); if (error) return (error); be = conn->lc_server->ls_backend; error = be->link != NULL ? be->link(be->softc, req) : ENOSYS; return (error); } static int l9p_dispatch_tmkdir(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_REQUIRE_DIR | F_FORBID_OPEN, &req->lr_fid); if (error) return (error); /* Slashes embedded in the name are not allowed */ if (strchr(req->lr_req.tlcreate.name, '/') != NULL) return (EINVAL); be = conn->lc_server->ls_backend; error = be->mkdir != NULL ? be->mkdir(be->softc, req) : ENOSYS; return (error); } static int l9p_dispatch_trenameat(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_REQUIRE_DIR, &req->lr_fid); if (error) return (error); error = fid_lookup(conn, req->lr_req.trenameat.newdirfid, ENOENT, F_REQUIRE_DIR, &req->lr_fid2); if (error) return (error); be = conn->lc_server->ls_backend; /* TODO: check old and new names */ error = be->renameat != NULL ? be->renameat(be->softc, req) : ENOSYS; return (error); } static int l9p_dispatch_tunlinkat(struct l9p_request *req) { struct l9p_connection *conn = req->lr_conn; struct l9p_backend *be; int error; error = fid_lookup(conn, req->lr_req.hdr.fid, ENOENT, F_REQUIRE_DIR, &req->lr_fid); if (error) return (error); be = conn->lc_server->ls_backend; /* TODO: check dir-or-file name */ error = be->unlinkat != NULL ? be->unlinkat(be->softc, req) : ENOSYS; return (error); }