ref: 3efb5bbb4061056e523858b134c555949591efe2
dir: /appl/cmd/listen.b/
implement Listen;
include "sys.m";
sys: Sys;
include "draw.m";
include "arg.m";
include "keyring.m";
keyring: Keyring;
include "security.m";
auth: Auth;
include "dial.m";
dial: Dial;
include "sh.m";
sh: Sh;
Context: import sh;
Listen: module {
init: fn(nil: ref Draw->Context, argv: list of string);
};
badmodule(p: string)
{
sys->fprint(stderr(), "listen: cannot load %s: %r\n", p);
raise "fail:bad module";
}
serverkey: ref Keyring->Authinfo;
verbose := 0;
init(drawctxt: ref Draw->Context, argv: list of string)
{
sys = load Sys Sys->PATH;
keyring = load Keyring Keyring->PATH;
auth = load Auth Auth->PATH;
if (auth == nil)
badmodule(Auth->PATH);
dial = load Dial Dial->PATH;
if (dial == nil)
badmodule(Dial->PATH);
sh = load Sh Sh->PATH;
if (sh == nil)
badmodule(Sh->PATH);
arg := load Arg Arg->PATH;
if (arg == nil)
badmodule(Arg->PATH);
auth->init();
algs: list of string;
arg->init(argv);
keyfile: string;
initscript: string;
doauth := 1;
synchronous := 0;
trusted := 0;
arg->setusage("listen [-i {initscript}] [-Ast] [-k keyfile] [-a alg]... addr command [arg...]");
while ((opt := arg->opt()) != 0) {
case opt {
'a' =>
algs = arg->earg() :: algs;
'A' =>
doauth = 0;
'f' or
'k' =>
keyfile = arg->earg();
if (! (keyfile[0] == '/' || (len keyfile > 2 && keyfile[0:2] == "./")))
keyfile = "/usr/" + user() + "/keyring/" + keyfile;
'i' =>
initscript = arg->earg();
'v' =>
verbose = 1;
's' =>
synchronous = 1;
't' =>
trusted = 1;
* =>
arg->usage();
}
}
if (doauth && algs == nil)
algs = getalgs();
if (algs != nil) {
if (keyfile == nil)
keyfile = "/usr/" + user() + "/keyring/default";
serverkey = keyring->readauthinfo(keyfile);
if (serverkey == nil) {
sys->fprint(stderr(), "listen: cannot read %s: %r\n", keyfile);
raise "fail:bad keyfile";
}
}
if(!trusted){
sys->unmount(nil, "/mnt/keys"); # should do for now
# become none?
}
argv = arg->argv();
n := len argv;
if (n < 2)
arg->usage();
arg = nil;
sync := chan[1] of string;
spawn listen(drawctxt, hd argv, tl argv, algs, initscript, sync);
e := <-sync;
if(e != nil)
raise "fail:" + e;
if(synchronous){
e = <-sync;
if(e != nil)
raise "fail:" + e;
}
}
listen(drawctxt: ref Draw->Context, addr: string, argv: list of string,
algs: list of string, initscript: string, sync: chan of string)
{
{
listen1(drawctxt, addr, argv, algs, initscript, sync);
} exception e {
"fail:*" =>
sync <-= e;
}
}
listen1(drawctxt: ref Draw->Context, addr: string, argv: list of string,
algs: list of string, initscript: string, sync: chan of string)
{
sys->pctl(Sys->FORKFD, nil);
ctxt := Context.new(drawctxt);
acon := dial->announce(addr);
if (acon == nil) {
sys->fprint(stderr(), "listen: failed to announce on '%s': %r\n", addr);
sync <-= "cannot announce";
exit;
}
ctxt.set("user", nil);
if (initscript != nil) {
ctxt.setlocal("net", ref Sh->Listnode(nil, acon.dir) :: nil);
ctxt.run(ref Sh->Listnode(nil, initscript) :: nil, 0);
initscript = nil;
}
# make sure the shell command is parsed only once.
cmd := sh->stringlist2list(argv);
if((hd argv) != nil && (hd argv)[0] == '{'){
(c, e) := sh->parse(hd argv);
if(c == nil){
sys->fprint(stderr(), "listen: %s\n", e);
sync <-= "parse error";
exit;
}
cmd = ref Sh->Listnode(c, hd argv) :: tl cmd;
}
sync <-= nil;
listench := chan of (int, ref Dial->Connection);
authch := chan of (string, ref Dial->Connection);
spawn listener(listench, acon, addr);
for (;;) {
user := "";
ccon: ref Dial->Connection;
alt {
(lok, c) := <-listench =>
if (lok == -1){
sync <-= "listen";
exit;
}
if (algs != nil) {
spawn authenticator(authch, c, algs, addr);
continue;
}
ccon = c;
(user, ccon) = <-authch =>
;
}
if (user != nil)
ctxt.set("user", sh->stringlist2list(user :: nil));
ctxt.set("net", ref Sh->Listnode(nil, ccon.dir) :: nil);
# XXX could do this in a separate process too, to
# allow new connections to arrive and start authenticating
# while the shell command is still running.
sys->dup(ccon.dfd.fd, 0);
sys->dup(ccon.dfd.fd, 1);
ccon.dfd = ccon.cfd = nil;
ctxt.run(cmd, 0);
sys->dup(2, 0);
sys->dup(2, 1);
}
}
listener(listench: chan of (int, ref Dial->Connection), c: ref Dial->Connection, addr: string)
{
for (;;) {
nc := dial->listen(c);
if (nc == nil) {
sys->fprint(stderr(), "listen: listen error on '%s': %r\n", addr);
listench <-= (-1, nc);
exit;
}
if (verbose)
sys->fprint(stderr(), "listen: got connection on %s from %s",
addr, readfile(nc.dir + "/remote"));
nc.dfd = dial->accept(nc);
if (nc.dfd == nil)
sys->fprint(stderr(), "listen: cannot open %s: %r\n", nc.dir + "/data");
else{
if(nc.cfd != nil)
sys->fprint(nc.cfd, "keepalive");
listench <-= (0, nc);
}
}
}
authenticator(authch: chan of (string, ref Dial->Connection),
c: ref Dial->Connection, algs: list of string, addr: string)
{
err: string;
(c.dfd, err) = auth->server(algs, serverkey, c.dfd, 0);
if (c.dfd == nil) {
sys->fprint(stderr(), "listen: auth on %s failed: %s\n", addr, err);
return;
}
if (verbose)
sys->fprint(stderr(), "listen: authenticated on %s as %s\n", addr, err);
authch <-= (err, c);
}
stderr(): ref Sys->FD
{
return sys->fildes(2);
}
user(): string
{
u := readfile("/dev/user");
if (u == nil)
return "nobody";
return u;
}
readfile(f: string): string
{
fd := sys->open(f, sys->OREAD);
if(fd == nil)
return nil;
buf := array[1024] of byte;
n := sys->read(fd, buf, len buf);
if(n < 0)
return nil;
return string buf[0:n];
}
getalgs(): list of string
{
sslctl := readfile("#D/clone");
if (sslctl == nil) {
sslctl = readfile("#D/ssl/clone");
if (sslctl == nil)
return nil;
sslctl = "#D/ssl/" + sslctl;
} else
sslctl = "#D/" + sslctl;
(nil, algs) := sys->tokenize(readfile(sslctl + "/encalgs") + " " + readfile(sslctl + "/hashalgs"), " \t\n");
return "none" :: algs;
}