X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/71276795b0a68665fc7aa5e20a3b4433a4cd9d39..a27002e5cd012026c6b5462babe81f6a5633a543:/key.c

diff --git a/key.c b/key.c
index d474f85c..b101e1b2 100644
--- a/key.c
+++ b/key.c
@@ -1,5 +1,15 @@
 /*
- * Copyright (c) 2000 Markus Friedl.  All rights reserved.
+ * read_bignum():
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ *
+ * As far as I am concerned, the code I have written for this software
+ * can be used freely for any purpose.  Any derived versions of this
+ * software must be clearly marked as such, and if the derived work is
+ * incompatible with the protocol description in the RFC file, it must be
+ * called by a name other than "ssh" or "Secure Shell".
+ *
+ *
+ * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -9,11 +19,6 @@
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- *    must display the following acknowledgement:
- *      This product includes software developed by Markus Friedl.
- * 4. The name of the author may not be used to endorse or promote products
- *    derived from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
@@ -26,22 +31,18 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
-/*
- * read_bignum():
- * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
- */
-
 #include "includes.h"
-#include "ssh.h"
-#include <openssl/rsa.h>
-#include <openssl/dsa.h>
+RCSID("$OpenBSD: key.c,v 1.53 2003/06/24 08:23:46 markus Exp $");
+
 #include <openssl/evp.h>
+
 #include "xmalloc.h"
 #include "key.h"
-#include "dsa.h"
+#include "rsa.h"
 #include "uuencode.h"
-
-#define SSH_DSS "ssh-dss"
+#include "buffer.h"
+#include "bufaux.h"
+#include "log.h"
 
 Key *
 key_new(int type)
@@ -51,24 +52,34 @@ key_new(int type)
 	DSA *dsa;
 	k = xmalloc(sizeof(*k));
 	k->type = type;
+	k->flags = 0;
 	k->dsa = NULL;
 	k->rsa = NULL;
 	switch (k->type) {
+	case KEY_RSA1:
 	case KEY_RSA:
-		rsa = RSA_new();
-		rsa->n = BN_new();
-		rsa->e = BN_new();
+		if ((rsa = RSA_new()) == NULL)
+			fatal("key_new: RSA_new failed");
+		if ((rsa->n = BN_new()) == NULL)
+			fatal("key_new: BN_new failed");
+		if ((rsa->e = BN_new()) == NULL)
+			fatal("key_new: BN_new failed");
 		k->rsa = rsa;
 		break;
 	case KEY_DSA:
-		dsa = DSA_new();
-		dsa->p = BN_new();
-		dsa->q = BN_new();
-		dsa->g = BN_new();
-		dsa->pub_key = BN_new();
+		if ((dsa = DSA_new()) == NULL)
+			fatal("key_new: DSA_new failed");
+		if ((dsa->p = BN_new()) == NULL)
+			fatal("key_new: BN_new failed");
+		if ((dsa->q = BN_new()) == NULL)
+			fatal("key_new: BN_new failed");
+		if ((dsa->g = BN_new()) == NULL)
+			fatal("key_new: BN_new failed");
+		if ((dsa->pub_key = BN_new()) == NULL)
+			fatal("key_new: BN_new failed");
 		k->dsa = dsa;
 		break;
-	case KEY_EMPTY:
+	case KEY_UNSPEC:
 		break;
 	default:
 		fatal("key_new: bad key type %d", k->type);
@@ -76,10 +87,44 @@ key_new(int type)
 	}
 	return k;
 }
+
+Key *
+key_new_private(int type)
+{
+	Key *k = key_new(type);
+	switch (k->type) {
+	case KEY_RSA1:
+	case KEY_RSA:
+		if ((k->rsa->d = BN_new()) == NULL)
+			fatal("key_new_private: BN_new failed");
+		if ((k->rsa->iqmp = BN_new()) == NULL)
+			fatal("key_new_private: BN_new failed");
+		if ((k->rsa->q = BN_new()) == NULL)
+			fatal("key_new_private: BN_new failed");
+		if ((k->rsa->p = BN_new()) == NULL)
+			fatal("key_new_private: BN_new failed");
+		if ((k->rsa->dmq1 = BN_new()) == NULL)
+			fatal("key_new_private: BN_new failed");
+		if ((k->rsa->dmp1 = BN_new()) == NULL)
+			fatal("key_new_private: BN_new failed");
+		break;
+	case KEY_DSA:
+		if ((k->dsa->priv_key = BN_new()) == NULL)
+			fatal("key_new_private: BN_new failed");
+		break;
+	case KEY_UNSPEC:
+		break;
+	default:
+		break;
+	}
+	return k;
+}
+
 void
 key_free(Key *k)
 {
 	switch (k->type) {
+	case KEY_RSA1:
 	case KEY_RSA:
 		if (k->rsa != NULL)
 			RSA_free(k->rsa);
@@ -90,6 +135,8 @@ key_free(Key *k)
 			DSA_free(k->dsa);
 		k->dsa = NULL;
 		break;
+	case KEY_UNSPEC:
+		break;
 	default:
 		fatal("key_free: bad key type %d", k->type);
 		break;
@@ -102,6 +149,7 @@ key_equal(Key *a, Key *b)
 	if (a == NULL || b == NULL || a->type != b->type)
 		return 0;
 	switch (a->type) {
+	case KEY_RSA1:
 	case KEY_RSA:
 		return a->rsa != NULL && b->rsa != NULL &&
 		    BN_cmp(a->rsa->e, b->rsa->e) == 0 &&
@@ -121,22 +169,31 @@ key_equal(Key *a, Key *b)
 	return 0;
 }
 
-#define FPRINT "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x"
-
-/*
- * Generate key fingerprint in ascii format.
- * Based on ideas and code from Bjoern Groenvall <bg@sics.se>
- */
-char *
-key_fingerprint(Key *k)
+u_char*
+key_fingerprint_raw(Key *k, enum fp_type dgst_type, u_int *dgst_raw_length)
 {
-	static char retval[80];
-	unsigned char *blob = NULL;
-	int len = 0;
+	const EVP_MD *md = NULL;
+	EVP_MD_CTX ctx;
+	u_char *blob = NULL;
+	u_char *retval = NULL;
+	u_int len = 0;
 	int nlen, elen;
 
+	*dgst_raw_length = 0;
+
+	switch (dgst_type) {
+	case SSH_FP_MD5:
+		md = EVP_md5();
+		break;
+	case SSH_FP_SHA1:
+		md = EVP_sha1();
+		break;
+	default:
+		fatal("key_fingerprint_raw: bad digest type %d",
+		    dgst_type);
+	}
 	switch (k->type) {
-	case KEY_RSA:
+	case KEY_RSA1:
 		nlen = BN_num_bytes(k->rsa->n);
 		elen = BN_num_bytes(k->rsa->e);
 		len = nlen + elen;
@@ -145,27 +202,120 @@ key_fingerprint(Key *k)
 		BN_bn2bin(k->rsa->e, blob + nlen);
 		break;
 	case KEY_DSA:
-		dsa_make_key_blob(k, &blob, &len);
+	case KEY_RSA:
+		key_to_blob(k, &blob, &len);
+		break;
+	case KEY_UNSPEC:
+		return retval;
 		break;
 	default:
-		fatal("key_fingerprint: bad key type %d", k->type);
+		fatal("key_fingerprint_raw: bad key type %d", k->type);
 		break;
 	}
 	if (blob != NULL) {
-		unsigned char d[16];
-		EVP_MD_CTX md;
-		EVP_DigestInit(&md, EVP_md5());
-		EVP_DigestUpdate(&md, blob, len);
-		EVP_DigestFinal(&md, d, NULL);
-		snprintf(retval, sizeof(retval), FPRINT,
-		    d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7],
-		    d[8], d[9], d[10], d[11], d[12], d[13], d[14], d[15]);
+		retval = xmalloc(EVP_MAX_MD_SIZE);
+		EVP_DigestInit(&ctx, md);
+		EVP_DigestUpdate(&ctx, blob, len);
+		EVP_DigestFinal(&ctx, retval, dgst_raw_length);
 		memset(blob, 0, len);
 		xfree(blob);
+	} else {
+		fatal("key_fingerprint_raw: blob is null");
 	}
 	return retval;
 }
 
+static char *
+key_fingerprint_hex(u_char *dgst_raw, u_int dgst_raw_len)
+{
+	char *retval;
+	int i;
+
+	retval = xmalloc(dgst_raw_len * 3 + 1);
+	retval[0] = '\0';
+	for (i = 0; i < dgst_raw_len; i++) {
+		char hex[4];
+		snprintf(hex, sizeof(hex), "%02x:", dgst_raw[i]);
+		strlcat(retval, hex, dgst_raw_len * 3);
+	}
+	retval[(dgst_raw_len * 3) - 1] = '\0';
+	return retval;
+}
+
+static char *
+key_fingerprint_bubblebabble(u_char *dgst_raw, u_int dgst_raw_len)
+{
+	char vowels[] = { 'a', 'e', 'i', 'o', 'u', 'y' };
+	char consonants[] = { 'b', 'c', 'd', 'f', 'g', 'h', 'k', 'l', 'm',
+	    'n', 'p', 'r', 's', 't', 'v', 'z', 'x' };
+	u_int i, j = 0, rounds, seed = 1;
+	char *retval;
+
+	rounds = (dgst_raw_len / 2) + 1;
+	retval = xmalloc(sizeof(char) * (rounds*6));
+	retval[j++] = 'x';
+	for (i = 0; i < rounds; i++) {
+		u_int idx0, idx1, idx2, idx3, idx4;
+		if ((i + 1 < rounds) || (dgst_raw_len % 2 != 0)) {
+			idx0 = (((((u_int)(dgst_raw[2 * i])) >> 6) & 3) +
+			    seed) % 6;
+			idx1 = (((u_int)(dgst_raw[2 * i])) >> 2) & 15;
+			idx2 = ((((u_int)(dgst_raw[2 * i])) & 3) +
+			    (seed / 6)) % 6;
+			retval[j++] = vowels[idx0];
+			retval[j++] = consonants[idx1];
+			retval[j++] = vowels[idx2];
+			if ((i + 1) < rounds) {
+				idx3 = (((u_int)(dgst_raw[(2 * i) + 1])) >> 4) & 15;
+				idx4 = (((u_int)(dgst_raw[(2 * i) + 1]))) & 15;
+				retval[j++] = consonants[idx3];
+				retval[j++] = '-';
+				retval[j++] = consonants[idx4];
+				seed = ((seed * 5) +
+				    ((((u_int)(dgst_raw[2 * i])) * 7) +
+				    ((u_int)(dgst_raw[(2 * i) + 1])))) % 36;
+			}
+		} else {
+			idx0 = seed % 6;
+			idx1 = 16;
+			idx2 = seed / 6;
+			retval[j++] = vowels[idx0];
+			retval[j++] = consonants[idx1];
+			retval[j++] = vowels[idx2];
+		}
+	}
+	retval[j++] = 'x';
+	retval[j++] = '\0';
+	return retval;
+}
+
+char *
+key_fingerprint(Key *k, enum fp_type dgst_type, enum fp_rep dgst_rep)
+{
+	char *retval = NULL;
+	u_char *dgst_raw;
+	u_int dgst_raw_len;
+
+	dgst_raw = key_fingerprint_raw(k, dgst_type, &dgst_raw_len);
+	if (!dgst_raw)
+		fatal("key_fingerprint: null from key_fingerprint_raw()");
+	switch (dgst_rep) {
+	case SSH_FP_HEX:
+		retval = key_fingerprint_hex(dgst_raw, dgst_raw_len);
+		break;
+	case SSH_FP_BUBBLEBABBLE:
+		retval = key_fingerprint_bubblebabble(dgst_raw, dgst_raw_len);
+		break;
+	default:
+		fatal("key_fingerprint_ex: bad digest representation %d",
+		    dgst_rep);
+		break;
+	}
+	memset(dgst_raw, 0, dgst_raw_len);
+	xfree(dgst_raw);
+	return retval;
+}
+
 /*
  * Reads a multiple-precision integer in decimal from the buffer, and advances
  * the pointer.  The integer must already be initialized.  This function is
@@ -173,7 +323,7 @@ key_fingerprint(Key *k)
  * last processed (and maybe modified) character.  Note that this may modify
  * the buffer containing the number.
  */
-int
+static int
 read_bignum(char **cpp, BIGNUM * value)
 {
 	char *cp = *cpp;
@@ -209,7 +359,8 @@ read_bignum(char **cpp, BIGNUM * value)
 	*cpp = cp;
 	return 1;
 }
-int
+
+static int
 write_bignum(FILE *f, BIGNUM *num)
 {
 	char *buf = BN_bn2dec(num);
@@ -218,59 +369,110 @@ write_bignum(FILE *f, BIGNUM *num)
 		return 0;
 	}
 	fprintf(f, " %s", buf);
-	free(buf);
+	OPENSSL_free(buf);
 	return 1;
 }
-unsigned int
+
+/* returns 1 ok, -1 error */
+int
 key_read(Key *ret, char **cpp)
 {
 	Key *k;
-	unsigned int bits = 0;
-	char *cp;
-	int len, n;
-	unsigned char *blob;
+	int success = -1;
+	char *cp, *space;
+	int len, n, type;
+	u_int bits;
+	u_char *blob;
 
 	cp = *cpp;
 
-	switch(ret->type) {
-	case KEY_RSA:
+	switch (ret->type) {
+	case KEY_RSA1:
 		/* Get number of bits. */
 		if (*cp < '0' || *cp > '9')
-			return 0;	/* Bad bit count... */
+			return -1;	/* Bad bit count... */
 		for (bits = 0; *cp >= '0' && *cp <= '9'; cp++)
 			bits = 10 * bits + *cp - '0';
 		if (bits == 0)
-			return 0;
+			return -1;
 		*cpp = cp;
 		/* Get public exponent, public modulus. */
 		if (!read_bignum(cpp, ret->rsa->e))
-			return 0;
+			return -1;
 		if (!read_bignum(cpp, ret->rsa->n))
-			return 0;
+			return -1;
+		success = 1;
 		break;
+	case KEY_UNSPEC:
+	case KEY_RSA:
 	case KEY_DSA:
-		if (strncmp(cp, SSH_DSS " ", 7) != 0)
-			return 0;
-		cp += 7;
+		space = strchr(cp, ' ');
+		if (space == NULL) {
+			debug3("key_read: missing whitespace");
+			return -1;
+		}
+		*space = '\0';
+		type = key_type_from_name(cp);
+		*space = ' ';
+		if (type == KEY_UNSPEC) {
+			debug3("key_read: missing keytype");
+			return -1;
+		}
+		cp = space+1;
+		if (*cp == '\0') {
+			debug3("key_read: short string");
+			return -1;
+		}
+		if (ret->type == KEY_UNSPEC) {
+			ret->type = type;
+		} else if (ret->type != type) {
+			/* is a key, but different type */
+			debug3("key_read: type mismatch");
+			return -1;
+		}
 		len = 2*strlen(cp);
 		blob = xmalloc(len);
 		n = uudecode(cp, blob, len);
 		if (n < 0) {
 			error("key_read: uudecode %s failed", cp);
-			return 0;
+			xfree(blob);
+			return -1;
 		}
-		k = dsa_key_from_blob(blob, n);
+		k = key_from_blob(blob, (u_int)n);
+		xfree(blob);
 		if (k == NULL) {
-			error("key_read: dsa_key_from_blob %s failed", cp);
-			return 0;
+			error("key_read: key_from_blob %s failed", cp);
+			return -1;
 		}
-		xfree(blob);
-		if (ret->dsa != NULL)
-			DSA_free(ret->dsa);
-		ret->dsa = k->dsa;
-		k->dsa = NULL;
+		if (k->type != type) {
+			error("key_read: type mismatch: encoding error");
+			key_free(k);
+			return -1;
+		}
+/*XXXX*/
+		if (ret->type == KEY_RSA) {
+			if (ret->rsa != NULL)
+				RSA_free(ret->rsa);
+			ret->rsa = k->rsa;
+			k->rsa = NULL;
+			success = 1;
+#ifdef DEBUG_PK
+			RSA_print_fp(stderr, ret->rsa, 8);
+#endif
+		} else {
+			if (ret->dsa != NULL)
+				DSA_free(ret->dsa);
+			ret->dsa = k->dsa;
+			k->dsa = NULL;
+			success = 1;
+#ifdef DEBUG_PK
+			DSA_print_fp(stderr, ret->dsa, 8);
+#endif
+		}
+/*XXXX*/
 		key_free(k);
-		bits = BN_num_bits(ret->dsa->p);
+		if (success != 1)
+			break;
 		/* advance cp: skip whitespace and data */
 		while (*cp == ' ' || *cp == '\t')
 			cp++;
@@ -282,15 +484,18 @@ key_read(Key *ret, char **cpp)
 		fatal("key_read: bad key type: %d", ret->type);
 		break;
 	}
-	return bits;
+	return success;
 }
+
 int
 key_write(Key *key, FILE *f)
 {
-	int success = 0;
-	unsigned int bits = 0;
+	int n, success = 0;
+	u_int len, bits = 0;
+	u_char *blob;
+	char *uu;
 
-	if (key->type == KEY_RSA && key->rsa != NULL) {
+	if (key->type == KEY_RSA1 && key->rsa != NULL) {
 		/* size of modulus 'n' */
 		bits = BN_num_bits(key->rsa->n);
 		fprintf(f, "%u", bits);
@@ -300,14 +505,13 @@ key_write(Key *key, FILE *f)
 		} else {
 			error("key_write: failed for RSA key");
 		}
-	} else if (key->type == KEY_DSA && key->dsa != NULL) {
-		int len, n;
-		unsigned char *blob, *uu;
-		dsa_make_key_blob(key, &blob, &len);
+	} else if ((key->type == KEY_DSA && key->dsa != NULL) ||
+	    (key->type == KEY_RSA && key->rsa != NULL)) {
+		key_to_blob(key, &blob, &len);
 		uu = xmalloc(2*len);
 		n = uuencode(blob, len, uu, 2*len);
 		if (n > 0) {
-			fprintf(f, "%s %s", SSH_DSS, uu);
+			fprintf(f, "%s %s", key_ssh_name(key), uu);
 			success = 1;
 		}
 		xfree(blob);
@@ -315,10 +519,14 @@ key_write(Key *key, FILE *f)
 	}
 	return success;
 }
+
 char *
 key_type(Key *k)
 {
 	switch (k->type) {
+	case KEY_RSA1:
+		return "RSA1";
+		break;
 	case KEY_RSA:
 		return "RSA";
 		break;
@@ -328,3 +536,319 @@ key_type(Key *k)
 	}
 	return "unknown";
 }
+
+char *
+key_ssh_name(Key *k)
+{
+	switch (k->type) {
+	case KEY_RSA:
+		return "ssh-rsa";
+		break;
+	case KEY_DSA:
+		return "ssh-dss";
+		break;
+	}
+	return "ssh-unknown";
+}
+
+u_int
+key_size(Key *k)
+{
+	switch (k->type) {
+	case KEY_RSA1:
+	case KEY_RSA:
+		return BN_num_bits(k->rsa->n);
+		break;
+	case KEY_DSA:
+		return BN_num_bits(k->dsa->p);
+		break;
+	}
+	return 0;
+}
+
+static RSA *
+rsa_generate_private_key(u_int bits)
+{
+	RSA *private;
+	private = RSA_generate_key(bits, 35, NULL, NULL);
+	if (private == NULL)
+		fatal("rsa_generate_private_key: key generation failed.");
+	return private;
+}
+
+static DSA*
+dsa_generate_private_key(u_int bits)
+{
+	DSA *private = DSA_generate_parameters(bits, NULL, 0, NULL, NULL, NULL, NULL);
+	if (private == NULL)
+		fatal("dsa_generate_private_key: DSA_generate_parameters failed");
+	if (!DSA_generate_key(private))
+		fatal("dsa_generate_private_key: DSA_generate_key failed.");
+	if (private == NULL)
+		fatal("dsa_generate_private_key: NULL.");
+	return private;
+}
+
+Key *
+key_generate(int type, u_int bits)
+{
+	Key *k = key_new(KEY_UNSPEC);
+	switch (type) {
+	case KEY_DSA:
+		k->dsa = dsa_generate_private_key(bits);
+		break;
+	case KEY_RSA:
+	case KEY_RSA1:
+		k->rsa = rsa_generate_private_key(bits);
+		break;
+	default:
+		fatal("key_generate: unknown type %d", type);
+	}
+	k->type = type;
+	return k;
+}
+
+Key *
+key_from_private(Key *k)
+{
+	Key *n = NULL;
+	switch (k->type) {
+	case KEY_DSA:
+		n = key_new(k->type);
+		BN_copy(n->dsa->p, k->dsa->p);
+		BN_copy(n->dsa->q, k->dsa->q);
+		BN_copy(n->dsa->g, k->dsa->g);
+		BN_copy(n->dsa->pub_key, k->dsa->pub_key);
+		break;
+	case KEY_RSA:
+	case KEY_RSA1:
+		n = key_new(k->type);
+		BN_copy(n->rsa->n, k->rsa->n);
+		BN_copy(n->rsa->e, k->rsa->e);
+		break;
+	default:
+		fatal("key_from_private: unknown type %d", k->type);
+		break;
+	}
+	return n;
+}
+
+int
+key_type_from_name(char *name)
+{
+	if (strcmp(name, "rsa1") == 0) {
+		return KEY_RSA1;
+	} else if (strcmp(name, "rsa") == 0) {
+		return KEY_RSA;
+	} else if (strcmp(name, "dsa") == 0) {
+		return KEY_DSA;
+	} else if (strcmp(name, "ssh-rsa") == 0) {
+		return KEY_RSA;
+	} else if (strcmp(name, "ssh-dss") == 0) {
+		return KEY_DSA;
+	}
+	debug2("key_type_from_name: unknown key type '%s'", name);
+	return KEY_UNSPEC;
+}
+
+int
+key_names_valid2(const char *names)
+{
+	char *s, *cp, *p;
+
+	if (names == NULL || strcmp(names, "") == 0)
+		return 0;
+	s = cp = xstrdup(names);
+	for ((p = strsep(&cp, ",")); p && *p != '\0';
+	    (p = strsep(&cp, ","))) {
+		switch (key_type_from_name(p)) {
+		case KEY_RSA1:
+		case KEY_UNSPEC:
+			xfree(s);
+			return 0;
+		}
+	}
+	debug3("key names ok: [%s]", names);
+	xfree(s);
+	return 1;
+}
+
+Key *
+key_from_blob(u_char *blob, u_int blen)
+{
+	Buffer b;
+	char *ktype;
+	int rlen, type;
+	Key *key = NULL;
+
+#ifdef DEBUG_PK
+	dump_base64(stderr, blob, blen);
+#endif
+	buffer_init(&b);
+	buffer_append(&b, blob, blen);
+	ktype = buffer_get_string(&b, NULL);
+	type = key_type_from_name(ktype);
+
+	switch (type) {
+	case KEY_RSA:
+		key = key_new(type);
+		buffer_get_bignum2(&b, key->rsa->e);
+		buffer_get_bignum2(&b, key->rsa->n);
+#ifdef DEBUG_PK
+		RSA_print_fp(stderr, key->rsa, 8);
+#endif
+		break;
+	case KEY_DSA:
+		key = key_new(type);
+		buffer_get_bignum2(&b, key->dsa->p);
+		buffer_get_bignum2(&b, key->dsa->q);
+		buffer_get_bignum2(&b, key->dsa->g);
+		buffer_get_bignum2(&b, key->dsa->pub_key);
+#ifdef DEBUG_PK
+		DSA_print_fp(stderr, key->dsa, 8);
+#endif
+		break;
+	case KEY_UNSPEC:
+		key = key_new(type);
+		break;
+	default:
+		error("key_from_blob: cannot handle type %s", ktype);
+		break;
+	}
+	rlen = buffer_len(&b);
+	if (key != NULL && rlen != 0)
+		error("key_from_blob: remaining bytes in key blob %d", rlen);
+	xfree(ktype);
+	buffer_free(&b);
+	return key;
+}
+
+int
+key_to_blob(Key *key, u_char **blobp, u_int *lenp)
+{
+	Buffer b;
+	int len;
+
+	if (key == NULL) {
+		error("key_to_blob: key == NULL");
+		return 0;
+	}
+	buffer_init(&b);
+	switch (key->type) {
+	case KEY_DSA:
+		buffer_put_cstring(&b, key_ssh_name(key));
+		buffer_put_bignum2(&b, key->dsa->p);
+		buffer_put_bignum2(&b, key->dsa->q);
+		buffer_put_bignum2(&b, key->dsa->g);
+		buffer_put_bignum2(&b, key->dsa->pub_key);
+		break;
+	case KEY_RSA:
+		buffer_put_cstring(&b, key_ssh_name(key));
+		buffer_put_bignum2(&b, key->rsa->e);
+		buffer_put_bignum2(&b, key->rsa->n);
+		break;
+	default:
+		error("key_to_blob: unsupported key type %d", key->type);
+		buffer_free(&b);
+		return 0;
+	}
+	len = buffer_len(&b);
+	if (lenp != NULL)
+		*lenp = len;
+	if (blobp != NULL) {
+		*blobp = xmalloc(len);
+		memcpy(*blobp, buffer_ptr(&b), len);
+	}
+	memset(buffer_ptr(&b), 0, len);
+	buffer_free(&b);
+	return len;
+}
+
+int
+key_sign(
+    Key *key,
+    u_char **sigp, u_int *lenp,
+    u_char *data, u_int datalen)
+{
+	switch (key->type) {
+	case KEY_DSA:
+		return ssh_dss_sign(key, sigp, lenp, data, datalen);
+		break;
+	case KEY_RSA:
+		return ssh_rsa_sign(key, sigp, lenp, data, datalen);
+		break;
+	default:
+		error("key_sign: illegal key type %d", key->type);
+		return -1;
+		break;
+	}
+}
+
+/*
+ * key_verify returns 1 for a correct signature, 0 for an incorrect signature
+ * and -1 on error.
+ */
+int
+key_verify(
+    Key *key,
+    u_char *signature, u_int signaturelen,
+    u_char *data, u_int datalen)
+{
+	if (signaturelen == 0)
+		return -1;
+
+	switch (key->type) {
+	case KEY_DSA:
+		return ssh_dss_verify(key, signature, signaturelen, data, datalen);
+		break;
+	case KEY_RSA:
+		return ssh_rsa_verify(key, signature, signaturelen, data, datalen);
+		break;
+	default:
+		error("key_verify: illegal key type %d", key->type);
+		return -1;
+		break;
+	}
+}
+
+/* Converts a private to a public key */
+Key *
+key_demote(Key *k)
+{
+	Key *pk;
+
+	pk = xmalloc(sizeof(*pk));
+	pk->type = k->type;
+	pk->flags = k->flags;
+	pk->dsa = NULL;
+	pk->rsa = NULL;
+
+	switch (k->type) {
+	case KEY_RSA1:
+	case KEY_RSA:
+		if ((pk->rsa = RSA_new()) == NULL)
+			fatal("key_demote: RSA_new failed");
+		if ((pk->rsa->e = BN_dup(k->rsa->e)) == NULL)
+			fatal("key_demote: BN_dup failed");
+		if ((pk->rsa->n = BN_dup(k->rsa->n)) == NULL)
+			fatal("key_demote: BN_dup failed");
+		break;
+	case KEY_DSA:
+		if ((pk->dsa = DSA_new()) == NULL)
+			fatal("key_demote: DSA_new failed");
+		if ((pk->dsa->p = BN_dup(k->dsa->p)) == NULL)
+			fatal("key_demote: BN_dup failed");
+		if ((pk->dsa->q = BN_dup(k->dsa->q)) == NULL)
+			fatal("key_demote: BN_dup failed");
+		if ((pk->dsa->g = BN_dup(k->dsa->g)) == NULL)
+			fatal("key_demote: BN_dup failed");
+		if ((pk->dsa->pub_key = BN_dup(k->dsa->pub_key)) == NULL)
+			fatal("key_demote: BN_dup failed");
+		break;
+	default:
+		fatal("key_free: bad key type %d", k->type);
+		break;
+	}
+
+	return (pk);
+}