1 files changed, 71 insertions, 0 deletions
diff --git a/src/cmd/auth/asn12rsa.c b/src/cmd/auth/asn12rsa.c
new file mode 100644
index 00000000..a2df0447
--- /dev/null
+++ b/src/cmd/auth/asn12rsa.c
@@ -0,0 +1,71 @@
+#include <u.h>
+#include <libc.h>
+#include <bio.h>
+#include <mp.h>
+#include <libsec.h>
+
+void
+usage(void)
+{
+	fprint(2, "auth/asn12rsa [-t tag] [file]\n");
+	exits("usage");
+}
+
+void
+main(int argc, char **argv)
+{
+	char *s;
+	uchar *buf;
+	int fd;
+	long n, tot;
+	char *tag, *file;
+	RSApriv *key;
+
+	fmtinstall('B', mpfmt);
+
+	tag = nil;
+	ARGBEGIN{
+	case 't':
+		tag = EARGF(usage());
+		break;
+	default:
+		usage();
+	}ARGEND
+
+	if(argc != 0 && argc != 1)
+		usage();
+
+	if(argc == 1)
+		file = argv[0];
+	else
+		file = "/dev/stdin";
+
+	if((fd = open(file, OREAD)) < 0)
+		sysfatal("open %s: %r", file);
+	buf = nil;
+	tot = 0;
+	for(;;){
+		buf = realloc(buf, tot+8192);
+		if(buf == nil)
+			sysfatal("realloc: %r");
+		if((n = read(fd, buf+tot, 8192)) < 0)
+			sysfatal("read: %r");
+		if(n == 0)
+			break;
+		tot += n;
+	}
+
+	key = asn1toRSApriv(buf, tot);
+	if(key == nil)
+		sysfatal("couldn't parse asn1 key");
+
+	s = smprint("key proto=rsa %s%ssize=%d ek=%B !dk=%B n=%B !p=%B !q=%B !kp=%B !kq=%B !c2=%B\n",
+		tag ? tag : "", tag ? " " : "",
+		mpsignif(key->pub.n), key->pub.ek,
+		key->dk, key->pub.n, key->p, key->q,
+		key->kp, key->kq, key->c2);
+	if(s == nil)
+		sysfatal("smprint: %r");
+	write(1, s, strlen(s));
+	exits(0);
+}