/*  * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ #include <u.h>#include <libc.h>#include <mp.h>#include <ctype.h>#include <libsec.h>#include <fcall.h>#include <thread.h>#include <9p.h>#include "netssh.h" enum {	Arbsz =	256,}; static intparsepubkey(char *s, RSApub *key, char **sp, int base){	int n;	char *host, *p, *z; 	z = nil;	n = strtoul(s, &p, 10);	host = nil;	if(n < Arbsz || !isspace(*p)){		/* maybe this is a host name */		host = s;		s = strpbrk(s, " \t");		if(s == nil)			return -1;		z = s;		*s++ = '\0';		s += strspn(s, " \t"); 		n = strtoul(s, &p, 10);		if(n < Arbsz || !isspace(*p)){			if(z)				*z = ' ';			return -1;		}	} 	/* Arbsz is just a sanity check */	if((key->ek = strtomp(p, &p, base, nil)) == nil ||	    (key->n = strtomp(p, &p, base, nil)) == nil ||	    (*p != '\0' && !isspace(*p)) || mpsignif(key->n) < Arbsz) {		mpfree(key->ek);		mpfree(key->n);		key->ek = nil;		key->n = nil;		if(z)			*z = ' ';		return -1;	}	if(host == nil){		if(*p != '\0'){			p += strspn(p, " \t");			if(*p != '\0'){				host = emalloc9p(strlen(p)+1);				strcpy(host, p);			}		}		free(s);	}	*sp = host;	return 0;} RSApub*readpublickey(Biobuf *b, char **sp){	char *s;	RSApub *key; 	key = emalloc9p(sizeof(RSApub));	if(key == nil)		return nil; 	for (; (s = Brdstr(b, '\n', 1)) != nil; free(s))		if(s[0] != '#'){			if(parsepubkey(s, key, sp, 10) == 0 ||			    parsepubkey(s, key, sp, 16) == 0)				return key;			fprint(2, "warning: skipping line '%s'; cannot parse\n",				s);		}	free(key);	return nil;} static intmatch(char *pattern, char *aliases){	char *s, *snext, *a, *anext, *ae; 	for(s = pattern; s && *s; s = snext){		if((snext = strchr(s, ',')) != nil)			*snext++ = '\0';		for(a = aliases; a && *a; a = anext){			if((anext = strchr(a, ',')) != nil){				ae = anext;				anext++;			}else				ae = a + strlen(a);			if(ae - a == strlen(s) && memcmp(s, a, ae - a) == 0)				return 0;		}	}	return 1;} intfindkey(char *keyfile, char *host, RSApub *key){	char *h;	Biobuf *b;	RSApub *k;	int res; 	if ((b = Bopen(keyfile, OREAD)) == nil)		return NoKeyFile; 	for (res = NoKey; res != KeyOk;) {		if ((k = readpublickey(b, &h)) == nil)			break;		if (match(h, host) == 0) {			if (mpcmp(k->n, key->n) == 0 &&			    mpcmp(k->ek, key->ek) == 0)				res = KeyOk;			else				res = KeyWrong;		}		free(h);		free(k->ek);		free(k->n);		free(k);	}	Bterm(b);	return res;} intreplacekey(char *keyfile, char *host, RSApub *hostkey){	int ret;	char *h, *nkey, *p;	Biobuf *br, *bw;	Dir *d, nd;	RSApub *k; 	ret = -1;	d = nil;	nkey = smprint("%s.new", keyfile);	if(nkey == nil)		return -1; 	if((br = Bopen(keyfile, OREAD)) == nil)		goto out;	if((bw = Bopen(nkey, OWRITE)) == nil){		Bterm(br);		goto out;	} 	while((k = readpublickey(br, &h)) != nil){		if(match(h, host) != 0)			Bprint(bw, "%s %d %.10M %.10M\n",				h, mpsignif(k->n), k->ek, k->n);		free(h);		rsapubfree(k);	}	Bprint(bw, "%s %d %.10M %.10M\n", host, mpsignif(hostkey->n),		hostkey->ek, hostkey->n);	Bterm(bw);	Bterm(br); 	d = dirstat(nkey);	if(d == nil){		fprint(2, "new key file disappeared?\n");		goto out;	} 	p = strrchr(d->name, '.');	if(p == nil || strcmp(p, ".new") != 0){		fprint(2, "%s: new key file changed names? %s to %s\n",			argv0, nkey, d->name);		goto out;	} 	*p = '\0';	nulldir(&nd);	nd.name = d->name;	if(remove(keyfile) < 0){		fprint(2, "%s: error removing %s: %r\n", argv0, keyfile);		goto out;	}	if(dirwstat(nkey, &nd) < 0){		fprint(2, "%s: error renaming %s to %s: %r\n",			argv0, nkey, d->name);		goto out;	}	ret = 0;out:	free(d);	free(nkey);	return ret;} intappendkey(char *keyfile, char *host, RSApub *key){	int fd, ret; 	ret = -1;	if((fd = open(keyfile, OWRITE)) < 0){		fd = create(keyfile, OWRITE, 0666);		if(fd < 0){			fprint(2, "%s: can't open nor create %s: %r\n",				argv0, keyfile);			return -1;		}	}	if(seek(fd, 0, 2) >= 0 &&	    fprint(fd, "%s %d %.10M %.10M\n", host, mpsignif(key->n),	     key->ek, key->n) >= 0)		ret = 0;	close(fd);	return ret;}