Import sources from 2011-03-30 iso image

1 files changed, 227 insertions, 0 deletions

diff --git a/sys/src/cmd/ssh/pubkey.c b/sys/src/cmd/ssh/pubkey.c
new file mode 100755
index 000000000..0c170b843
--- /dev/null
+++ b/sys/src/cmd/ssh/pubkey.c
@@ -0,0 +1,227 @@
+#include "ssh.h"
+#include <bio.h>
+#include <ctype.h>
+
+static int
+parsepubkey(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 < 256 || !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 < 256 || !isspace(*p)){
+			if(z)
+				*z = ' ';
+			return -1;
+		}
+	}
+
+	if((key->ek = strtomp(p, &p, base, nil)) == nil
+	|| (key->n = strtomp(p, &p, base, nil)) == nil
+	|| (*p != '\0' && !isspace(*p))
+	|| mpsignif(key->n) < 256){	/* 256 is just a sanity check */
+		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 = emalloc(strlen(p)+1);
+				strcpy(host, p);
+			}
+		}
+		free(s);
+	}
+	*sp = host;
+	return 0;
+}
+
+RSApub*
+readpublickey(Biobuf *b, char **sp)
+{
+	char *s;
+	RSApub *key;
+
+	key = rsapuballoc();
+	if(key == nil)
+		return nil;
+
+	for(;;){
+		if((s = Brdstr(b, '\n', 1)) == nil){
+			rsapubfree(key);
+			return nil;
+		}
+		if(s[0]=='#'){
+			free(s);
+			continue;
+		}
+		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(s);
+	}
+}
+
+static int
+match(char *pattern, char *aliases)
+{
+	char *s, *snext;
+	char *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;
+}
+
+int
+findkey(char *keyfile, char *host, RSApub *key)
+{
+	char *h;
+	Biobuf *b;
+	RSApub *k;
+
+	if((b = Bopen(keyfile, OREAD)) == nil)
+		return NoKeyFile;
+
+	for(;;){
+		if((k = readpublickey(b, &h)) == nil){
+			Bterm(b);
+			return NoKey;
+		}
+		if(match(h, host) != 0){
+			free(h);
+			rsapubfree(k);
+			continue;
+		}
+		if(mpcmp(k->n, key->n) != 0 || mpcmp(k->ek, key->ek) != 0){
+			free(h);
+			rsapubfree(k);
+			Bterm(b);
+			return KeyWrong;
+		}
+		free(h);
+		rsapubfree(k);
+		Bterm(b);
+		return KeyOk;
+	}
+}
+
+int
+replacekey(char *keyfile, char *host, RSApub *hostkey)
+{
+	char *h, *nkey, *p;
+	Biobuf *br, *bw;
+	Dir *d, nd;
+	RSApub *k;
+
+	nkey = smprint("%s.new", keyfile);
+	if(nkey == nil)
+		return -1;
+
+	if((br = Bopen(keyfile, OREAD)) == nil){
+		free(nkey);
+		return -1;
+	}
+	if((bw = Bopen(nkey, OWRITE)) == nil){
+		Bterm(br);
+		free(nkey);
+		return -1;
+	}
+
+	while((k = readpublickey(br, &h)) != nil){
+		if(match(h, host) != 0){
+			Bprint(bw, "%s %d %.10B %.10B\n",
+				h, mpsignif(k->n), k->ek, k->n);
+		}
+		free(h);
+		rsapubfree(k);
+	}
+	Bprint(bw, "%s %d %.10B %.10B\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");
+		free(nkey);
+		return -1;
+	}
+
+	p = strrchr(d->name, '.');
+	if(p==nil || strcmp(p, ".new")!=0){
+		fprint(2, "new key file changed names? %s to %s\n", nkey, d->name);
+		free(d);
+		free(nkey);
+		return -1;
+	}
+
+	*p = '\0';
+	nulldir(&nd);
+	nd.name = d->name;
+	if(remove(keyfile) < 0){
+		fprint(2, "error removing %s: %r\n", keyfile);
+		free(d);
+		free(nkey);
+		return -1;
+	}
+	if(dirwstat(nkey, &nd) < 0){
+		fprint(2, "error renaming %s to %s: %r\n", nkey, d->name);
+		free(nkey);
+		free(d);
+		return -1;
+	}
+	free(d);
+	free(nkey);
+	return 0;
+}
+
+int
+appendkey(char *keyfile, char *host, RSApub *key)
+{
+	int fd;
+
+	if((fd = open(keyfile, OWRITE)) < 0){
+		fd = create(keyfile, OWRITE, 0666);
+		if(fd < 0){
+			fprint(2, "cannot open nor create %s: %r\n", keyfile);
+			return -1;
+		}
+	}
+	if(seek(fd, 0, 2) < 0
+	|| fprint(fd, "%s %d %.10B %.10B\n", host, mpsignif(key->n), key->ek, key->n) < 0){
+		close(fd);
+		return -1;
+	}
+	close(fd);
+	return 0;
+}