ref: dfb4b522830edab8f3856289d326d6cf5e930644
dir: /sys/src/cmd/ip/ftpfs/ftpfs.c/
#include <u.h> #include <libc.h> #include <auth.h> #include <fcall.h> #include <String.h> #include "ftpfs.h" /* an active fid */ typedef struct Fid Fid; struct Fid { int fid; Node *node; /* path to remote file */ int busy; Fid *next; int open; }; Fid *fids; /* linked list of fids */ char errstring[128]; /* error to return */ int mfd; /* fd for 9fs */ int messagesize = IOUNIT+IOHDRSZ; uchar mdata[IOUNIT+IOHDRSZ]; uchar mbuf[IOUNIT]; Fcall rhdr; Fcall thdr; int debug; int usenlst; int usetls; char *ext; int quiet; int kapid = -1; int dying; /* set when any process decides to die */ int dokeepalive; char *rflush(Fid*), *rnop(Fid*), *rversion(Fid*), *rattach(Fid*), *rclone(Fid*), *rwalk(Fid*), *rclwalk(Fid*), *ropen(Fid*), *rcreate(Fid*), *rread(Fid*), *rwrite(Fid*), *rclunk(Fid*), *rremove(Fid*), *rstat(Fid*), *rwstat(Fid*), *rauth(Fid*);; void mountinit(char*); void io(void); int readpdir(Node*); char *(*fcalls[])(Fid*) = { [Tflush] rflush, [Tversion] rversion, [Tattach] rattach, [Tauth] rauth, [Twalk] rwalk, [Topen] ropen, [Tcreate] rcreate, [Tread] rread, [Twrite] rwrite, [Tclunk] rclunk, [Tremove] rremove, [Tstat] rstat, [Twstat] rwstat, }; /* these names are matched as prefixes, so VMS must precede VM */ OS oslist[] = { { Plan9, "Plan 9", }, { Plan9, "Plan9", }, { Plan9, "UNIX Type: L8 Version: Plan 9", }, { Unix, "SUN", }, { Unix, "UNIX", }, { VMS, "VMS", }, { VM, "VM", }, { Tops, "TOPS", }, { MVS, "MVS", }, { NetWare, "NetWare", }, { NetWare, "NETWARE", }, { OS½, "OS/2", }, { TSO, "TSO", }, { NT, "Windows_NT", }, /* DOS like interface */ { NT, "WINDOWS_NT", }, /* Unix like interface */ { Unknown, 0 }, }; char *nouid = "?uid?"; #define S2P(x) (((ulong)(x)) & 0xffffff) char *nosuchfile = "file does not exist"; char *keyspec = ""; int docache = 0; void usage(void) { fprint(2, "ftpfs [-/dqnt] [-a passwd] [-m mountpoint] [-e ext] [-k keyspec] [-o os] [-r root] address\n"); exits("usage"); } void main(int argc, char *argv[]) { char *mountroot = 0; char *mountpoint = "/n/ftp"; char *cpassword = 0; char *cp; int p[2]; OS *o; defos = Unix; user = strdup(getuser()); usetls = 0; ARGBEGIN { case '/': mountroot = "/"; break; case 'a': cpassword = ARGF(); break; case 'd': debug = 1; break; case 'k': keyspec = EARGF(usage()); break; case 'K': dokeepalive = 1; break; case 'm': mountpoint = ARGF(); break; case 'n': usenlst = 1; break; case 'e': ext = ARGF(); break; case 't': usetls = 1; break; case 'o': cp = ARGF(); for(o = oslist; o->os != Unknown; o++) if(strncmp(cp, o->name, strlen(o->name)) == 0){ defos = o->os; break; } break; case 'r': mountroot = ARGF(); break; case 'q': quiet = 1; break; case 'c': docache = 1; break; } ARGEND if(argc != 1) usage(); /* get a pipe to mount and run 9fs on */ if(pipe(p) < 0) fatal("pipe failed: %r"); mfd = p[0]; /* initial handshakes with remote side */ hello(*argv); if(cpassword == 0) rlogin(*argv, keyspec); else clogin("anonymous", cpassword); preamble(mountroot); /* start the 9fs protocol */ switch(rfork(RFPROC|RFNAMEG|RFENVG|RFFDG|RFNOTEG|RFREND)){ case -1: fatal("fork: %r"); case 0: /* seal off standard input/output */ close(0); open("/dev/null", OREAD); close(1); open("/dev/null", OWRITE); close(p[1]); fmtinstall('F', fcallfmt); /* debugging */ fmtinstall('D', dirfmt); /* expected by %F */ fmtinstall('M', dirmodefmt); /* expected by %F */ io(); quit(); break; default: close(p[0]); if(mount(p[1], -1, mountpoint, MREPL|MCREATE, "") == -1) fatal("mount failed: %r"); } exits(0); } /* * lookup an fid. if not found, create a new one. */ Fid * newfid(int fid) { Fid *f, *ff; ff = 0; for(f = fids; f; f = f->next){ if(f->fid == fid){ if(f->busy) return f; else{ ff = f; break; } } else if(!ff && !f->busy) ff = f; } if(ff == 0){ ff = mallocz(sizeof(*f), 1); ff->next = fids; fids = ff; } ff->node = nil; ff->fid = fid; return ff; } /* * a process that sends keep alive messages to * keep the server from shutting down the connection */ int kaproc(void) { int pid; if(!dokeepalive) return -1; switch(pid = rfork(RFPROC|RFMEM)){ case -1: return -1; case 0: break; default: return pid; } while(!dying){ sleep(5000); nop(); } _exits(0); return -1; } void io(void) { char *err; int n; kapid = kaproc(); while(!dying){ n = read9pmsg(mfd, mdata, messagesize); if(n == 0) break; if(n < 0) fatal("mount read: %r"); if(convM2S(mdata, n, &thdr) != n) fatal("convM2S format error: %r"); if(debug) fprint(2, "<-%F\n", &thdr);/**/ if(!fcalls[thdr.type]) err = "bad fcall type"; else err = (*fcalls[thdr.type])(newfid(thdr.fid)); if(err){ rhdr.type = Rerror; rhdr.ename = err; }else{ rhdr.type = thdr.type + 1; rhdr.fid = thdr.fid; } rhdr.tag = thdr.tag; if(debug) fprint(2, "->%F\n", &rhdr);/**/ n = convS2M(&rhdr, mdata, messagesize); if(write(mfd, mdata, n) != n) fatal("mount write"); } } char* rnop(Fid *f) { USED(f); return 0; } char* rversion(Fid*) { if(thdr.msize < 256) return "version: message size too small"; if(thdr.msize > sizeof mdata) rhdr.msize = sizeof mdata; else rhdr.msize = thdr.msize; messagesize = rhdr.msize; rhdr.version = "9P2000"; if(strncmp(thdr.version, "9P", 2) != 0) rhdr.version = "unknown"; return nil; } char* rflush(Fid*) { return 0; } char* rauth(Fid*) { return "auth unimplemented"; } char* rattach(Fid *f) { f->busy = 1; f->node = remroot; rhdr.qid = f->node->d->qid; return 0; } char* rwalk(Fid *f) { Node *np; Fid *nf; char **elems; int i, nelems; char *err; Node *node; /* clone fid */ nf = nil; if(thdr.newfid != thdr.fid){ nf = newfid(thdr.newfid); if(nf->busy) return "newfid in use"; nf->busy = 1; nf->node = f->node; f = nf; } err = nil; elems = thdr.wname; nelems = thdr.nwname; node = f->node; rhdr.nwqid = 0; if(nelems > 0){ /* walk fid */ for(i=0; i<nelems && i<MAXWELEM; i++){ if((node->d->qid.type & QTDIR) == 0){ err = "not a directory"; break; } if(strcmp(elems[i], ".") == 0){ Found: rhdr.wqid[i] = node->d->qid; rhdr.nwqid++; continue; } if(strcmp(elems[i], "..") == 0){ node = node->parent; goto Found; } if(strcmp(elems[i], ".flush.ftpfs") == 0){ /* hack to flush the cache */ invalidate(node); readdir(node); goto Found; } /* some top level names are special */ if((os == Tops || os == VM || os == VMS) && node == remroot){ np = newtopsdir(elems[i]); if(np){ node = np; goto Found; } else { err = nosuchfile; break; } } /* everything else */ node = extendpath(node, s_copy(elems[i])); if(ISCACHED(node->parent)){ /* the cache of the parent is good, believe it */ if(!ISVALID(node)){ err = nosuchfile; break; } if(node->parent->chdirunknown || (node->d->mode & DMSYML)) fixsymbolic(node); } else if(!ISVALID(node)){ /* this isn't a valid node, try cd'ing */ if(changedir(node) == 0){ node->d->qid.type = QTDIR; node->d->mode |= DMDIR; }else{ node->d->qid.type = QTFILE; node->d->mode &= ~DMDIR; } } goto Found; } if(i == 0 && err == 0) err = "file does not exist"; } /* clunk a newly cloned fid if the walk didn't succeed */ if(nf != nil && (err != nil || rhdr.nwqid<nelems)){ nf->busy = 0; nf->fid = 0; } /* if it all worked, point the fid to the enw node */ if(err == nil) f->node = node; return err; } char * ropen(Fid *f) { int mode; mode = thdr.mode; if(f->node->d->qid.type & QTDIR) if(mode != OREAD) return "permission denied"; if(mode & OTRUNC){ uncache(f->node); uncache(f->node->parent); filedirty(f->node); } else { /* read the remote file or directory */ if(!ISCACHED(f->node)){ filefree(f->node); if(f->node->d->qid.type & QTDIR){ invalidate(f->node); if(readdir(f->node) < 0) return nosuchfile; } else { if(readfile(f->node) < 0) return errstring; } CACHED(f->node); } } rhdr.qid = f->node->d->qid; f->open = 1; f->node->opens++; return 0; } char* rcreate(Fid *f) { char *name; if((f->node->d->qid.type&QTDIR) == 0) return "not a directory"; name = thdr.name; f->node = extendpath(f->node, s_copy(name)); uncache(f->node); if(thdr.perm & DMDIR){ if(createdir(f->node) < 0) return "permission denied"; } else filedirty(f->node); invalidate(f->node->parent); uncache(f->node->parent); rhdr.qid = f->node->d->qid; f->open = 1; f->node->opens++; return 0; } char* rread(Fid *f) { long off; int n, cnt, rv; Node *np; rhdr.count = 0; off = thdr.offset; cnt = thdr.count; if(cnt > messagesize-IOHDRSZ) cnt = messagesize-IOHDRSZ; if(f->node->d->qid.type & QTDIR){ rv = 0; for(np = f->node->children; np != nil; np = np->sibs){ if(!ISVALID(np)) continue; if(off <= BIT16SZ) break; n = convD2M(np->d, mbuf, messagesize-IOHDRSZ); off -= n; } for(; rv < cnt && np != nil; np = np->sibs){ if(!ISVALID(np)) continue; if(np->d->mode & DMSYML) fixsymbolic(np); n = convD2M(np->d, mbuf + rv, cnt-rv); if(n <= BIT16SZ) break; rv += n; } } else { /* reread file if it's fallen out of the cache */ if(!ISCACHED(f->node)) if(readfile(f->node) < 0) return errstring; CACHED(f->node); rv = fileread(f->node, (char*)mbuf, off, cnt); if(rv < 0) return errstring; } rhdr.data = (char*)mbuf; rhdr.count = rv; return 0; } char* rwrite(Fid *f) { long off; int cnt; if(f->node->d->qid.type & QTDIR) return "directories are not writable"; rhdr.count = 0; off = thdr.offset; cnt = thdr.count; cnt = filewrite(f->node, thdr.data, off, cnt); if(cnt < 0) return errstring; filedirty(f->node); rhdr.count = cnt; return 0; } char * rclunk(Fid *f) { if(fileisdirty(f->node)){ if(createfile(f->node) < 0) fprint(2, "ftpfs: couldn't create %s\n", f->node->d->name); fileclean(f->node); uncache(f->node); } if(f->open){ f->open = 0; f->node->opens--; } f->busy = 0; if(!docache && ISCACHED(f->node)) uncache(f->node); return 0; } /* * remove is an implicit clunk */ char * rremove(Fid *f) { char *e; e = nil; if(QTDIR & f->node->d->qid.type){ if(removedir(f->node) < 0) e = errstring; } else { if(removefile(f->node) < 0) e = errstring; } uncache(f->node->parent); uncache(f->node); if(e == nil) INVALID(f->node); f->busy = 0; return e; } char * rstat(Fid *f) { Node *p; p = f->node->parent; if(!ISCACHED(p)){ invalidate(p); readdir(p); CACHED(p); } if(!ISVALID(f->node)) return nosuchfile; if(p->chdirunknown) fixsymbolic(f->node); rhdr.nstat = convD2M(f->node->d, mbuf, messagesize-IOHDRSZ); rhdr.stat = mbuf; return 0; } char * rwstat(Fid *f) { USED(f); return "wstat not implemented"; } /* * print message and die */ void fatal(char *fmt, ...) { va_list arg; char buf[1024]; dying = 1; va_start(arg, fmt); vseprint(buf, buf + (sizeof(buf)-1) / sizeof(*buf), fmt, arg); va_end(arg); fprint(2, "ftpfs: %s\n", buf); if(kapid > 0) postnote(PNGROUP, kapid, "die"); exits(buf); } /* * like strncpy but make sure there's a terminating null */ void* safecpy(void *to, void *from, int n) { char *a = ((char*)to) + n - 1; strncpy(to, from, n); *a = 0; return to; } /* * set the error string */ int seterr(char *fmt, ...) { va_list arg; va_start(arg, fmt); vsnprint(errstring, sizeof errstring, fmt, arg); va_end(arg); return -1; } /* * create a new node */ Node* newnode(Node *parent, String *name) { Node *np; static ulong path; Dir d; np = mallocz(sizeof(Node), 1); if(np == 0) fatal("out of memory"); np->children = 0; if(parent){ np->parent = parent; np->sibs = parent->children; parent->children = np; np->depth = parent->depth + 1; d.dev = 0; /* not stat'd */ } else { /* the root node */ np->parent = np; np->sibs = 0; np->depth = 0; d.dev = 1; } np->remname = name; d.name = s_to_c(name); d.atime = time(0); d.mtime = d.atime; d.uid = nouid; d.gid = nouid; d.muid = nouid; np->fp = 0; d.qid.path = ++path; d.qid.vers = 0; d.qid.type = QTFILE; d.type = 0; np->d = reallocdir(&d, 0); return np; } /* * walk one down the local mirror of the remote directory tree */ Node* extendpath(Node *parent, String *elem) { Node *np; for(np = parent->children; np; np = np->sibs) if(strcmp(s_to_c(np->remname), s_to_c(elem)) == 0){ s_free(elem); return np; } return newnode(parent, elem); } /* * flush the cached file, write it back if it's dirty */ void uncache(Node *np) { if(fileisdirty(np)) createfile(np); filefree(np); UNCACHED(np); } /* * invalidate all children of a node */ void invalidate(Node *node) { Node *np; if(node->opens) return; /* don't invalidate something that's open */ uncachedir(node, 0); /* invalidate children */ for(np = node->children; np; np = np->sibs){ if(np->opens) continue; /* don't invalidate something that's open */ UNCACHED(np); invalidate(np); np->d->dev = 0; } } /* * make a top level tops-20 directory. They are automaticly valid. */ Node* newtopsdir(char *name) { Node *np; np = extendpath(remroot, s_copy(name)); if(!ISVALID(np)){ np->d->qid.type = QTDIR; np->d->atime = time(0); np->d->mtime = np->d->atime; np->d->uid = "?uid?"; np->d->gid = "?uid?"; np->d->muid = "?uid?"; np->d->mode = DMDIR|0777; np->d->length = 0; np->d = reallocdir(np->d, 1); if(changedir(np) >= 0) VALID(np); } return np; } /* * figure out if a symbolic link is to a directory or a file */ void fixsymbolic(Node *node) { if(changedir(node) == 0){ node->d->mode |= DMDIR; node->d->qid.type = QTDIR; } else node->d->qid.type = QTFILE; node->d->mode &= ~DMSYML; }