#include <u.h>#include <libc.h>#include <bio.h>#include <auth.h>#include <authsrv.h>#include "authlocal.h" enum{	NARG	= 15,		/* max number of arguments */	MAXARG	= 10*ANAMELEN,	/* max length of an argument */}; static int	setenv(char*, char*);static char	*expandarg(char*, char*);static int	splitargs(char*, char*[], char*, int);static void	nsop(int, char*[], AuthRpc*);static int	callexport(char*, char*);static int	catch(void*, char*); static intbuildns(int newns, char *user, char *file){	Biobuf *spec;	char *cmd, *argv[NARG], argbuf[MAXARG*NARG];	char home[4*ANAMELEN];	int argc;	int afd;	AuthRpc *rpc; 	rpc = nil;	/* try for factotum now because later is impossible */	afd = open("/mnt/factotum/rpc", ORDWR);	if(afd >= 0){		rpc = auth_allocrpc(afd);		if(rpc == nil){			close(afd);			afd = -1;		}	}	if(newns && !file){		/* first look for a namespace file for this system */		snprint(home, sizeof(home), "/lib/namespace.%s", sysname());			if(access(home, 4) == 0)			file = home;		else			file = "/lib/namespace";	}	spec = Bopen(file, OREAD);	if(spec == 0){		werrstr("can't open %s: %r", file);		close(afd);		auth_freerpc(rpc);		return -1;	}	if(newns){		rfork(RFENVG|RFCNAMEG);		setenv("user", user);		snprint(home, 2*ANAMELEN, "/usr/%s", user);		setenv("home", home);	}	atnotify(catch, 1);	while(cmd = Brdline(spec, '\n')){		cmd[Blinelen(spec)-1] = '\0';		while(*cmd==' ' || *cmd=='\t')			cmd++;		if(*cmd == '#')			continue;		argc = splitargs(cmd, argv, argbuf, NARG);		if(argc)			nsop(argc, argv, rpc);	}	atnotify(catch, 0);	Bterm(spec);	if(rpc){		close(rpc->afd);		auth_freerpc(rpc);	}	return 0;} intnewns(char *user, char *file){	return buildns(1, user, file);} intaddns(char *user, char *file){	return buildns(0, user, file);} static intfamount(int fd, AuthRpc *rpc, char *mntpt, int flags, char *aname){	int afd;	AuthInfo *ai; 	afd = fauth(fd, aname);	if(afd >= 0){		ai = fauth_proxy(afd, rpc, amount_getkey, "proto=p9any role=client");		if(ai != nil)			auth_freeAI(ai);	}	return mount(fd, afd, mntpt, flags, aname);} static voidnsop(int argc, char *argv[], AuthRpc *rpc){	char *argv0;	ulong flags;	int fd; 	flags = 0;	argv0 = 0;	ARGBEGIN{	case 'a':		flags |= MAFTER;		break;	case 'b':		flags |= MBEFORE;		break;	case 'c':		flags |= MCREATE;		break;	case 'C':		flags |= MCACHE;		break;	}ARGEND 	if(!(flags & (MAFTER|MBEFORE)))		flags |= MREPL; 	if(strcmp(argv0, "bind") == 0 && argc == 2)		bind(argv[0], argv[1], flags);	else if(strcmp(argv0, "unmount") == 0){		if(argc == 1)			unmount(nil, argv[0]);		else if(argc == 2)			unmount(argv[0], argv[1]);	}else if(strcmp(argv0, "mount") == 0){		fd = open(argv[0], ORDWR);		if(argc == 2)			famount(fd, rpc, argv[1], flags, "");		else if(argc == 3)			famount(fd, rpc, argv[1], flags, argv[2]);		close(fd);	} else if(strcmp(argv0, "import") == 0){		fd = callexport(argv[0], argv[1]);		if(argc == 2)			famount(fd, rpc, argv[1], flags, "");		else if(argc == 3)			famount(fd, rpc, argv[2], flags, "");		close(fd);	} else if(strcmp(argv0, "cd") == 0 && argc == 1)		chdir(argv[0]);} static char *wocp = "sys: write on closed pipe"; static intcatch(void *x, char *m){	USED(x);	return strncmp(m, wocp, strlen(wocp)) == 0;} static intcallexport(char *sys, char *tree){	char *na, buf[3];	int fd;	AuthInfo *ai; 	na = netmkaddr(sys, 0, "exportfs");	if((fd = dial(na, 0, 0, 0)) < 0)		return -1;	if((ai = auth_proxy(fd, auth_getkey, "proto=p9any role=client")) == nil	|| write(fd, tree, strlen(tree)) < 0	|| read(fd, buf, 3) != 2 || buf[0]!='O' || buf[1]!= 'K'){		close(fd);		auth_freeAI(ai);		return -1;	}	auth_freeAI(ai);	return fd;} static intsplitargs(char *p, char *argv[], char *argbuf, int maxargs){	char *q;	int i; 	i = 0;	while(i < maxargs){		while(*p==' ' || *p=='\t')			p++;		if(!*p)			return i;		q = p;		while(*p && *p!=' ' && *p!='\t')			p++;		if(*p)			*p++ = '\0';		argv[i++] = argbuf;		argbuf = expandarg(q, argbuf);		if(!argbuf)			return 0;	}	return 0;} /* * copy the arg into the buffer, * expanding any environment variables. * environment variables are assumed to be * names (ie. < ANAMELEN long) * the entire argument is expanded to be at * most MAXARG long and null terminated * the address of the byte after the terminating null is returned * any problems cause a 0 return; */static char *expandarg(char *arg, char *buf){	char env[3+ANAMELEN], *p, *q;	int fd, n, len; 	n = 0;	while(p = utfrune(arg, L'$')){		len = p - arg;		if(n + len + ANAMELEN >= MAXARG-1)			return 0;		memmove(&buf[n], arg, len);		n += len;		p++;		arg = utfrune(p, L'\0');		q = utfrune(p, L'/');		if(q && q < arg)			arg = q;		q = utfrune(p, L'$');		if(q && q < arg)			arg = q;		len = arg - p;		if(len >= ANAMELEN)			continue;		strcpy(env, "#e/");		strncpy(env+3, p, len);		env[3+len] = '\0';		fd = open(env, OREAD);		if(fd >= 0){			len = read(fd, &buf[n], ANAMELEN - 1);			if(len > 0)				n += len;			close(fd);		}	}	len = strlen(arg);	if(n + len >= MAXARG - 1)		return 0;	strcpy(&buf[n], arg);	return &buf[n+len+1];} static intsetenv(char *name, char *val){	int f;	char ename[ANAMELEN+6];	long s; 	sprint(ename, "#e/%s", name);	f = create(ename, OWRITE, 0664);	if(f < 0)		return -1;	s = strlen(val);	if(write(f, val, s) != s){		close(f);		return -1;	}	close(f);	return 0;}