implement Tftpd; include "sys.m"; sys: Sys; stderr: ref Sys->FD; include "draw.m"; include "arg.m"; include "ip.m"; ip: IP; IPaddr, Udphdr: import ip; Tftpd: module{ init: fn (nil: ref Draw->Context, argv: list of string);}; dir:= "/services/tftpd";net:= "/net"; Tftp_READ: con 1;Tftp_WRITE: con 2;Tftp_DATA: con 3;Tftp_ACK: con 4;Tftp_ERROR: con 5; Segsize: con 512; dbg := 0;restricted := 0;port := 69; Udphdrsize: con IP->Udphdrlen; tftpcon: Sys->Connection;tftpreq: ref Sys->FD; dokill(pid: int, scope: string){ fd := sys->open("/prog/" + string pid + "/ctl", sys->OWRITE); if(fd == nil) fd = sys->open("#p/" + string pid + "/ctl", sys->OWRITE); if(fd != nil) sys->fprint(fd, "kill%s", scope);} kill(pid: int) { dokill(pid, ""); }killgrp(pid: int) { dokill(pid, "grp"); }killme() { kill(sys->pctl(0,nil)); }killus() { killgrp(sys->pctl(0,nil)); } DBG(s: string){ if(dbg) sys->fprint(stderr, "tfptd: %d: %s\n", sys->pctl(0,nil), s);} false, true: con iota; Timer: adt { KILL: con -1; ALARM: con -2; RETRY: con -3; sig: chan of int; create: fn(): ref Timer; destroy: fn(t: self ref Timer); set: fn(t: self ref Timer, msec, nretry: int); ticker: fn(t: self ref Timer); ticking: int; wakeup: int; timeout: int; nretry: int;}; Timer.create(): ref Timer{ t := ref Timer; t.wakeup = 0; t.ticking = false; t.sig = chan of int; return t;} Timer.destroy(t: self ref Timer){ DBG("Timer.destroy"); alt { t.sig <-= t.KILL => DBG("sent final msg"); * => DBG("couldn't send final msg"); } DBG("Timer.destroy done");} Timer.ticker(t: self ref Timer){ DBG("spawn: ticker"); t.ticking = true; while(t.wakeup > sys->millisec()) { DBG("Timer.ticker sleeping for " +string (t.wakeup-sys->millisec())); sys->sleep(t.wakeup-sys->millisec()); } if(t.wakeup) { DBG("Timer.ticker wakeup"); if(t.nretry) { alt { t.sig <-= t.RETRY => ; } t.ticking = false; t.set(t.timeout, t.nretry-1); } else alt { t.sig <-= t.ALARM => ; } } t.ticking = false; DBG("unspawn: ticker");} Timer.set(t: self ref Timer, msec, nretry: int){ DBG(sys->sprint("Timer.set(%d, %d)", msec, nretry)); if(msec == 0) { t.wakeup = 0; t.timeout = 0; t.nretry = 0; } else { t.wakeup = sys->millisec()+msec; t.timeout = msec; t.nretry = nretry; if(!t.ticking) spawn t.ticker(); }} killer(c: chan of int, pgid: int){ DBG("spawn: killer"); cmd := <- c; DBG(sys->sprint("killer has awakened (flag=%d)", cmd)); if(cmd == Timer.ALARM) { killgrp(pgid); DBG(sys->sprint("group %d has been killed", pgid)); } DBG("unspawn killer");} init(nil: ref Draw->Context, args: list of string){ sys = load Sys Sys->PATH; sys->pctl(Sys->NEWPGRP|Sys->FORKFD|Sys->FORKNS, nil); stderr = sys->fildes(2); arg := load Arg Arg->PATH; if(arg == nil) fatal("can't load Arg"); arg->init(args); arg->setusage("tftpd [-dr] [-p port] [-h homedir] [-x network-dir]"); while((o := arg->opt()) != 0) case o { 'd' => dbg++; 'h' => dir = arg->earg(); 'r' => restricted = 1; 'p' => port = int arg->earg(); 'x' => net = arg->earg(); * => arg->usage(); } args =arg->argv(); if(args != nil){ net = hd args; args = tl args; } if(args != nil) arg->usage(); arg = nil; ip = load IP IP->PATH; if(ip == nil) fatal(sys->sprint("can't load %s: %r", IP->PATH)); ip->init(); if(sys->chdir(dir) < 0) fatal("can't chdir to " + dir); spawn mainthing();} mainthing(){ DBG("spawn: mainthing"); bigbuf := array[32768] of byte; openlisten(); setuser(); for(;;) { dlen := sys->read(tftpreq, bigbuf, len bigbuf); if(dlen < 0) fatal("listen"); if(dlen < Udphdrsize) continue; hdr := Udphdr.unpack(bigbuf, Udphdrsize); raddr := sys->sprint("%s/udp!%s!%d", net, hdr.raddr.text(), hdr.rport); DBG(sys->sprint("raddr=%s", raddr)); (err, cx) := sys->dial(raddr, nil); if(err < 0) fatal("dialing "+raddr); # showbuf("bigbuf", bigbuf[0:dlen]); op := ip->get2(bigbuf, Udphdrsize); mbuf := bigbuf[Udphdrsize+2:dlen]; # get past Udphdr and op dlen -= 14; case op { Tftp_READ or Tftp_WRITE => ; Tftp_ERROR => DBG("tftp error"); continue; * => nak(cx.dfd, 4, "Illegal TFTP operation"); continue; } # showbuf("mbuf", mbuf[0:dlen]); i := 0; while(dlen > 0 && mbuf[i] != byte 0) { dlen--; i++; } p := i++; dlen--; while(dlen > 0 && mbuf[i] != byte 0) { dlen--; i++; } path := string mbuf[0:p]; mode := string mbuf[p+1:i]; DBG(sys->sprint("path = %s, mode = %s", path, mode)); if(dlen == 0) { nak(cx.dfd, 0, "bad tftpmode"); continue; } if(restricted && dodgy(path)){ nak(cx.dfd, 4, "Permission denied"); continue; } if(op == Tftp_READ) spawn sendfile(cx.dfd, path, mode); else spawn recvfile(cx.dfd, path, mode); } } dodgy(path: string): int{ n := len path; nd := len dir; if(n == 0 || path[0] == '#' || path[0] == '/' && (n < nd+1 || path[0:nd] != dir || path[nd] != '/')) return 1; (nil, flds) := sys->tokenize(path, "/"); for(; flds != nil; flds = tl flds) if(hd flds == "..") return 1; return 0;} showbuf(msg: string, b: array of byte){ sys->fprint(stderr, "%s: size %d: ", msg, len b); for(i:=0; i<len b; i++) sys->fprint(stderr, "%.2ux ", int b[i]); sys->fprint(stderr, "\n"); for(i=0; i<len b; i++) if(int b[i] >= 32 && int b[i] <= 126) sys->fprint(stderr, " %c", int b[i]); else sys->fprint(stderr, " ."); sys->fprint(stderr, "\n");} sendblock(sig: chan of int, buf: array of byte, net: ref sys->FD, ksig: chan of int){ DBG("spawn: sendblocks"); nbytes := 0; loop: for(;;) { DBG("sendblock: waiting for cmd"); cmd := <- sig; DBG(sys->sprint("sendblock: cmd=%d", cmd)); case cmd { Timer.KILL => DBG("sendblock: killed"); return; Timer.RETRY => ; Timer.ALARM => DBG("too many retries"); break loop; * => nbytes = cmd; }# showbuf("sendblock", buf[0:nbytes]); ret := sys->write(net, buf, 4+nbytes); DBG(sys->sprint("ret=%d", ret)); if(ret < 0) { ksig <-= Timer.ALARM; fatal("tftp: network write error"); } if(ret != 4+nbytes) return; } DBG("sendblock: exiting"); alt { ksig <-= Timer.ALARM => ; } DBG("unspawn: sendblocks");} sendfile(net: ref sys->FD, name: string, mode: string){ DBG(sys->sprint("spawn: sendfile: name=%s mode=%s", name, mode)); pgrp := sys->pctl(Sys->NEWPGRP, nil); ack := array[1024] of byte; if(name == "") { nak(net, 0, "not in our database"); return; } file := sys->open(name, Sys->OREAD); if(file == nil) { DBG(sys->sprint("open failed: %s", name)); errbuf := sys->sprint("%r"); nak(net, 0, errbuf); return; } DBG(sys->sprint("opened %s", name)); block := 0; timer := Timer.create(); ksig := chan of int; buf := array[4+Segsize] of byte; spawn killer(ksig, pgrp); spawn sendblock(timer.sig, buf, net, ksig); mainloop: for(;;) { block++; buf[0:] = array[] of {byte 0, byte Tftp_DATA, byte (block>>8), byte block}; n := sys->read(file, buf[4:], len buf-4); DBG(sys->sprint("n=%d", n)); if(n < 0) { errbuf := sys->sprint("%r"); nak(net, 0, errbuf); break; } DBG(sys->sprint("signalling write of %d to block %d", n, block)); timer.sig <-= n; for(rxl := 0; rxl < 10; rxl++) { timer.set(1000, 15); al := sys->read(net, ack, len ack); timer.set(0, 0); if(al < 0) { timer.sig <-= Timer.ALARM; break; } op := (int ack[0]<<8) | int ack[1]; if(op == Tftp_ERROR) break mainloop; ackblock := (int ack[2]<<8) | int ack[3]; DBG(sys->sprint("got ack: block=%d ackblock=%d", block, ackblock)); if(ackblock == block) break; if(ackblock == 16rffff) { block--; break; } } if(n < len buf-4) break; } timer.destroy(); ksig <-= Timer.KILL;} recvfile(fd: ref sys->FD, name: string, mode: string){ DBG(sys->sprint("spawn: recvfile: name=%s mode=%s", name, mode)); pgrp := sys->pctl(Sys->NEWPGRP, nil); file := sys->create(name, sys->OWRITE, 8r666); if(file == nil) { errbuf := sys->sprint("%r"); nak(fd, 0, errbuf); return; } block := 0; ack(fd, block); block++; buf := array[8+Segsize] of byte; timer := Timer.create(); spawn killer(timer.sig, pgrp); for(;;) { timer.set(15000, 0); DBG(sys->sprint("reading block %d", block)); n := sys->read(fd, buf, len buf); DBG(sys->sprint("read %d bytes", n)); timer.set(0, 0); if(n < 0) break; op := int buf[0]<<8 | int buf[1]; if(op == Tftp_ERROR) break; # showbuf("got", buf[0:n]); n -= 4; inblock := int buf[2]<<8 | int buf[3];# showbuf("hdr", buf[0:4]); if(op == Tftp_DATA) { if(inblock == block) { ret := sys->write(file, buf[4:], n); if(ret < 0) { errbuf := sys->sprint("%r"); nak(fd, 0, errbuf); break; } block++; } if(inblock < block) { ack(fd, inblock); DBG(sys->sprint("ok: inblock=%d block=%d", inblock, block)); } else DBG(sys->sprint("FAIL: inblock=%d block=%d", inblock, block)); ack(fd, 16rffff); if(n < 512) break; } } timer.destroy();} ack(fd: ref Sys->FD, block: int){ buf := array[] of {byte 0, byte Tftp_ACK, byte (block>>8), byte block};# showbuf("ack", buf); if(sys->write(fd, buf, 4) < 0) fatal("write ack");} nak(fd: ref Sys->FD, code: int, msg: string){sys->print("nak: %s\n", msg); buf := array[128] of {byte 0, byte Tftp_ERROR, byte 0, byte code}; bmsg := array of byte msg; buf[4:] = bmsg; buf[4+len bmsg] = byte 0; if(sys->write(fd, buf, 4+len bmsg+1) < 0) fatal("write nak");} fatal(msg: string){ sys->fprint(stderr, "tftpd: %s: %r\n", msg); killus(); raise "fail:error";} openlisten(){ name := net+"/udp!*!" + string port; err := 0; (err, tftpcon) = sys->announce(name); if(err < 0) fatal("can't announce "+name); if(sys->fprint(tftpcon.cfd, "headers") < 0) fatal("can't set header mode");Lines 1–500 of 512. Load more
implement Tftpd; include "sys.m"; sys: Sys; stderr: ref Sys->FD; include "draw.m"; include "arg.m"; include "ip.m"; ip: IP; IPaddr, Udphdr: import ip; Tftpd: module { init: fn (nil: ref Draw->Context, argv: list of string); }; dir:= "/services/tftpd"; net:= "/net"; Tftp_READ: con 1; Tftp_WRITE: con 2; Tftp_DATA: con 3; Tftp_ACK: con 4; Tftp_ERROR: con 5; Segsize: con 512; dbg := 0; restricted := 0; port := 69; Udphdrsize: con IP->Udphdrlen; tftpcon: Sys->Connection; tftpreq: ref Sys->FD; dokill(pid: int, scope: string) { fd := sys->open("/prog/" + string pid + "/ctl", sys->OWRITE); if(fd == nil) fd = sys->open("#p/" + string pid + "/ctl", sys->OWRITE); if(fd != nil) sys->fprint(fd, "kill%s", scope); } kill(pid: int) { dokill(pid, ""); } killgrp(pid: int) { dokill(pid, "grp"); } killme() { kill(sys->pctl(0,nil)); } killus() { killgrp(sys->pctl(0,nil)); } DBG(s: string) { if(dbg) sys->fprint(stderr, "tfptd: %d: %s\n", sys->pctl(0,nil), s); } false, true: con iota; Timer: adt { KILL: con -1; ALARM: con -2; RETRY: con -3; sig: chan of int; create: fn(): ref Timer; destroy: fn(t: self ref Timer); set: fn(t: self ref Timer, msec, nretry: int); ticker: fn(t: self ref Timer); ticking: int; wakeup: int; timeout: int; nretry: int; }; Timer.create(): ref Timer { t := ref Timer; t.wakeup = 0; t.ticking = false; t.sig = chan of int; return t; } Timer.destroy(t: self ref Timer) { DBG("Timer.destroy"); alt { t.sig <-= t.KILL => DBG("sent final msg"); * => DBG("couldn't send final msg"); } DBG("Timer.destroy done"); } Timer.ticker(t: self ref Timer) { DBG("spawn: ticker"); t.ticking = true; while(t.wakeup > sys->millisec()) { DBG("Timer.ticker sleeping for " +string (t.wakeup-sys->millisec())); sys->sleep(t.wakeup-sys->millisec()); } if(t.wakeup) { DBG("Timer.ticker wakeup"); if(t.nretry) { alt { t.sig <-= t.RETRY => ; } t.ticking = false; t.set(t.timeout, t.nretry-1); } else alt { t.sig <-= t.ALARM => ; } } t.ticking = false; DBG("unspawn: ticker"); } Timer.set(t: self ref Timer, msec, nretry: int) { DBG(sys->sprint("Timer.set(%d, %d)", msec, nretry)); if(msec == 0) { t.wakeup = 0; t.timeout = 0; t.nretry = 0; } else { t.wakeup = sys->millisec()+msec; t.timeout = msec; t.nretry = nretry; if(!t.ticking) spawn t.ticker(); } } killer(c: chan of int, pgid: int) { DBG("spawn: killer"); cmd := <- c; DBG(sys->sprint("killer has awakened (flag=%d)", cmd)); if(cmd == Timer.ALARM) { killgrp(pgid); DBG(sys->sprint("group %d has been killed", pgid)); } DBG("unspawn killer"); } init(nil: ref Draw->Context, args: list of string) { sys = load Sys Sys->PATH; sys->pctl(Sys->NEWPGRP|Sys->FORKFD|Sys->FORKNS, nil); stderr = sys->fildes(2); arg := load Arg Arg->PATH; if(arg == nil) fatal("can't load Arg"); arg->init(args); arg->setusage("tftpd [-dr] [-p port] [-h homedir] [-x network-dir]"); while((o := arg->opt()) != 0) case o { 'd' => dbg++; 'h' => dir = arg->earg(); 'r' => restricted = 1; 'p' => port = int arg->earg(); 'x' => net = arg->earg(); * => arg->usage(); } args =arg->argv(); if(args != nil){ net = hd args; args = tl args; } if(args != nil) arg->usage(); arg = nil; ip = load IP IP->PATH; if(ip == nil) fatal(sys->sprint("can't load %s: %r", IP->PATH)); ip->init(); if(sys->chdir(dir) < 0) fatal("can't chdir to " + dir); spawn mainthing(); } mainthing() { DBG("spawn: mainthing"); bigbuf := array[32768] of byte; openlisten(); setuser(); for(;;) { dlen := sys->read(tftpreq, bigbuf, len bigbuf); if(dlen < 0) fatal("listen"); if(dlen < Udphdrsize) continue; hdr := Udphdr.unpack(bigbuf, Udphdrsize); raddr := sys->sprint("%s/udp!%s!%d", net, hdr.raddr.text(), hdr.rport); DBG(sys->sprint("raddr=%s", raddr)); (err, cx) := sys->dial(raddr, nil); if(err < 0) fatal("dialing "+raddr); # showbuf("bigbuf", bigbuf[0:dlen]); op := ip->get2(bigbuf, Udphdrsize); mbuf := bigbuf[Udphdrsize+2:dlen]; # get past Udphdr and op dlen -= 14; case op { Tftp_READ or Tftp_WRITE => ; Tftp_ERROR => DBG("tftp error"); continue; * => nak(cx.dfd, 4, "Illegal TFTP operation"); continue; } # showbuf("mbuf", mbuf[0:dlen]); i := 0; while(dlen > 0 && mbuf[i] != byte 0) { dlen--; i++; } p := i++; dlen--; while(dlen > 0 && mbuf[i] != byte 0) { dlen--; i++; } path := string mbuf[0:p]; mode := string mbuf[p+1:i]; DBG(sys->sprint("path = %s, mode = %s", path, mode)); if(dlen == 0) { nak(cx.dfd, 0, "bad tftpmode"); continue; } if(restricted && dodgy(path)){ nak(cx.dfd, 4, "Permission denied"); continue; } if(op == Tftp_READ) spawn sendfile(cx.dfd, path, mode); else spawn recvfile(cx.dfd, path, mode); } } dodgy(path: string): int { n := len path; nd := len dir; if(n == 0 || path[0] == '#' || path[0] == '/' && (n < nd+1 || path[0:nd] != dir || path[nd] != '/')) return 1; (nil, flds) := sys->tokenize(path, "/"); for(; flds != nil; flds = tl flds) if(hd flds == "..") return 1; return 0; } showbuf(msg: string, b: array of byte) { sys->fprint(stderr, "%s: size %d: ", msg, len b); for(i:=0; i<len b; i++) sys->fprint(stderr, "%.2ux ", int b[i]); sys->fprint(stderr, "\n"); for(i=0; i<len b; i++) if(int b[i] >= 32 && int b[i] <= 126) sys->fprint(stderr, " %c", int b[i]); else sys->fprint(stderr, " ."); sys->fprint(stderr, "\n"); } sendblock(sig: chan of int, buf: array of byte, net: ref sys->FD, ksig: chan of int) { DBG("spawn: sendblocks"); nbytes := 0; loop: for(;;) { DBG("sendblock: waiting for cmd"); cmd := <- sig; DBG(sys->sprint("sendblock: cmd=%d", cmd)); case cmd { Timer.KILL => DBG("sendblock: killed"); return; Timer.RETRY => ; Timer.ALARM => DBG("too many retries"); break loop; * => nbytes = cmd; } # showbuf("sendblock", buf[0:nbytes]); ret := sys->write(net, buf, 4+nbytes); DBG(sys->sprint("ret=%d", ret)); if(ret < 0) { ksig <-= Timer.ALARM; fatal("tftp: network write error"); } if(ret != 4+nbytes) return; } DBG("sendblock: exiting"); alt { ksig <-= Timer.ALARM => ; } DBG("unspawn: sendblocks"); } sendfile(net: ref sys->FD, name: string, mode: string) { DBG(sys->sprint("spawn: sendfile: name=%s mode=%s", name, mode)); pgrp := sys->pctl(Sys->NEWPGRP, nil); ack := array[1024] of byte; if(name == "") { nak(net, 0, "not in our database"); return; } file := sys->open(name, Sys->OREAD); if(file == nil) { DBG(sys->sprint("open failed: %s", name)); errbuf := sys->sprint("%r"); nak(net, 0, errbuf); return; } DBG(sys->sprint("opened %s", name)); block := 0; timer := Timer.create(); ksig := chan of int; buf := array[4+Segsize] of byte; spawn killer(ksig, pgrp); spawn sendblock(timer.sig, buf, net, ksig); mainloop: for(;;) { block++; buf[0:] = array[] of {byte 0, byte Tftp_DATA, byte (block>>8), byte block}; n := sys->read(file, buf[4:], len buf-4); DBG(sys->sprint("n=%d", n)); if(n < 0) { errbuf := sys->sprint("%r"); nak(net, 0, errbuf); break; } DBG(sys->sprint("signalling write of %d to block %d", n, block)); timer.sig <-= n; for(rxl := 0; rxl < 10; rxl++) { timer.set(1000, 15); al := sys->read(net, ack, len ack); timer.set(0, 0); if(al < 0) { timer.sig <-= Timer.ALARM; break; } op := (int ack[0]<<8) | int ack[1]; if(op == Tftp_ERROR) break mainloop; ackblock := (int ack[2]<<8) | int ack[3]; DBG(sys->sprint("got ack: block=%d ackblock=%d", block, ackblock)); if(ackblock == block) break; if(ackblock == 16rffff) { block--; break; } } if(n < len buf-4) break; } timer.destroy(); ksig <-= Timer.KILL; } recvfile(fd: ref sys->FD, name: string, mode: string) { DBG(sys->sprint("spawn: recvfile: name=%s mode=%s", name, mode)); pgrp := sys->pctl(Sys->NEWPGRP, nil); file := sys->create(name, sys->OWRITE, 8r666); if(file == nil) { errbuf := sys->sprint("%r"); nak(fd, 0, errbuf); return; } block := 0; ack(fd, block); block++; buf := array[8+Segsize] of byte; timer := Timer.create(); spawn killer(timer.sig, pgrp); for(;;) { timer.set(15000, 0); DBG(sys->sprint("reading block %d", block)); n := sys->read(fd, buf, len buf); DBG(sys->sprint("read %d bytes", n)); timer.set(0, 0); if(n < 0) break; op := int buf[0]<<8 | int buf[1]; if(op == Tftp_ERROR) break; # showbuf("got", buf[0:n]); n -= 4; inblock := int buf[2]<<8 | int buf[3]; # showbuf("hdr", buf[0:4]); if(op == Tftp_DATA) { if(inblock == block) { ret := sys->write(file, buf[4:], n); if(ret < 0) { errbuf := sys->sprint("%r"); nak(fd, 0, errbuf); break; } block++; } if(inblock < block) { ack(fd, inblock); DBG(sys->sprint("ok: inblock=%d block=%d", inblock, block)); } else DBG(sys->sprint("FAIL: inblock=%d block=%d", inblock, block)); ack(fd, 16rffff); if(n < 512) break; } } timer.destroy(); } ack(fd: ref Sys->FD, block: int) { buf := array[] of {byte 0, byte Tftp_ACK, byte (block>>8), byte block}; # showbuf("ack", buf); if(sys->write(fd, buf, 4) < 0) fatal("write ack"); } nak(fd: ref Sys->FD, code: int, msg: string) { sys->print("nak: %s\n", msg); buf := array[128] of {byte 0, byte Tftp_ERROR, byte 0, byte code}; bmsg := array of byte msg; buf[4:] = bmsg; buf[4+len bmsg] = byte 0; if(sys->write(fd, buf, 4+len bmsg+1) < 0) fatal("write nak"); } fatal(msg: string) { sys->fprint(stderr, "tftpd: %s: %r\n", msg); killus(); raise "fail:error"; } openlisten() { name := net+"/udp!*!" + string port; err := 0; (err, tftpcon) = sys->announce(name); if(err < 0) fatal("can't announce "+name); if(sys->fprint(tftpcon.cfd, "headers") < 0) fatal("can't set header mode");