propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 20dccfc09627970a312d77fb41dc2970b62689c3)

            to branch 'au.asn.ucc.matt.dropbear' (head fdf4a7a3b97ae5046139915de7e40399cceb2c01)

--HG--
extra : convert_revision : dc4809882e1b9f2dcd3f8bbe38c74a0a52c39ce4

1 files changed, 187 insertions, 0 deletions

diff --git a/cli-authpubkey.c b/cli-authpubkey.c
new file mode 100644
index 0000000..9d36bc3
--- /dev/null
+++ b/cli-authpubkey.c
@@ -0,0 +1,187 @@
+/*
+ * Dropbear SSH
+ * 
+ * Copyright (c) 2002,2003 Matt Johnston
+ * Copyright (c) 2004 by Mihnea Stoenescu
+ * All rights reserved.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE. */
+
+#include "includes.h"
+#include "buffer.h"
+#include "dbutil.h"
+#include "session.h"
+#include "ssh.h"
+#include "runopts.h"
+#include "auth.h"
+
+#ifdef ENABLE_CLI_PUBKEY_AUTH
+static void send_msg_userauth_pubkey(sign_key *key, int type, int realsign);
+
+/* Called when we receive a SSH_MSG_USERAUTH_FAILURE for a pubkey request.
+ * We use it to remove the key we tried from the list */
+void cli_pubkeyfail() {
+
+	struct SignKeyList *keyitem;
+	struct SignKeyList **previtem;
+
+	TRACE(("enter cli_pubkeyfail"))
+	previtem = &cli_opts.privkeys;
+
+	/* Find the key we failed with, and remove it */
+	for (keyitem = cli_opts.privkeys; keyitem != NULL; keyitem = keyitem->next) {
+		if (keyitem == cli_ses.lastprivkey) {
+			*previtem = keyitem->next;
+		}
+		previtem = &keyitem;
+	}
+
+	sign_key_free(cli_ses.lastprivkey->key); /* It won't be used again */
+	m_free(cli_ses.lastprivkey);
+
+	TRACE(("leave cli_pubkeyfail"))
+}
+
+void recv_msg_userauth_pk_ok() {
+
+	struct SignKeyList *keyitem;
+	buffer* keybuf;
+	char* algotype = NULL;
+	unsigned int algolen;
+	int keytype;
+	unsigned int remotelen;
+
+	TRACE(("enter recv_msg_userauth_pk_ok"))
+
+	algotype = buf_getstring(ses.payload, &algolen);
+	keytype = signkey_type_from_name(algotype, algolen);
+	TRACE(("recv_msg_userauth_pk_ok: type %d", keytype))
+	m_free(algotype);
+
+	keybuf = buf_new(MAX_PUBKEY_SIZE);
+
+	remotelen = buf_getint(ses.payload);
+
+	/* Iterate through our keys, find which one it was that matched, and
+	 * send a real request with that key */
+	for (keyitem = cli_opts.privkeys; keyitem != NULL; keyitem = keyitem->next) {
+
+		if (keyitem->type != keytype) {
+			/* Types differed */
+			TRACE(("types differed"))
+			continue;
+		}
+
+		/* Now we compare the contents of the key */
+		keybuf->pos = keybuf->len = 0;
+		buf_put_pub_key(keybuf, keyitem->key, keytype);
+		buf_setpos(keybuf, 0);
+		buf_incrpos(keybuf, 4); /* first int is the length of the remainder (ie
+								   remotelen) which has already been taken from
+								   the remote buffer */
+
+
+		if (keybuf->len-4 != remotelen) {
+			TRACE(("lengths differed: localh %d remote %d", keybuf->len, remotelen))
+			/* Lengths differed */
+			continue;
+		}
+		if (memcmp(buf_getptr(keybuf, remotelen),
+					buf_getptr(ses.payload, remotelen), remotelen) != 0) {
+			/* Data didn't match this key */
+			TRACE(("data differed"))
+			continue;
+		}
+
+		/* Success */
+		break;
+	}
+
+	if (keyitem != NULL) {
+		TRACE(("matching key"))
+		/* XXX TODO: if it's an encrypted key, here we ask for their
+		 * password */
+		send_msg_userauth_pubkey(keyitem->key, keytype, 1);
+	} else {
+		TRACE(("That was whacky. We got told that a key was valid, but it didn't match our list. Sounds like dodgy code on Dropbear's part"))
+	}
+
+	TRACE(("leave recv_msg_userauth_pk_ok"))
+}
+
+/* TODO: make it take an agent reference to use as well */
+static void send_msg_userauth_pubkey(sign_key *key, int type, int realsign) {
+
+	const char *algoname = NULL;
+	int algolen;
+	buffer* sigbuf = NULL;
+
+	TRACE(("enter send_msg_userauth_pubkey"))
+	CHECKCLEARTOWRITE();
+
+	buf_putbyte(ses.writepayload, SSH_MSG_USERAUTH_REQUEST);
+
+	buf_putstring(ses.writepayload, cli_opts.username,
+			strlen(cli_opts.username));
+
+	buf_putstring(ses.writepayload, SSH_SERVICE_CONNECTION, 
+			SSH_SERVICE_CONNECTION_LEN);
+
+	buf_putstring(ses.writepayload, AUTH_METHOD_PUBKEY, 
+			AUTH_METHOD_PUBKEY_LEN);
+
+	buf_putbyte(ses.writepayload, realsign);
+
+	algoname = signkey_name_from_type(type, &algolen);
+
+	buf_putstring(ses.writepayload, algoname, algolen);
+	buf_put_pub_key(ses.writepayload, key, type);
+
+	if (realsign) {
+		TRACE(("realsign"))
+		/* We put the signature as well - this contains string(session id), then
+		 * the contents of the write payload to this point */
+		sigbuf = buf_new(4 + SHA1_HASH_SIZE + ses.writepayload->len);
+		buf_putstring(sigbuf, ses.session_id, SHA1_HASH_SIZE);
+		buf_putbytes(sigbuf, ses.writepayload->data, ses.writepayload->len);
+		buf_put_sign(ses.writepayload, key, type, sigbuf->data, sigbuf->len);
+		buf_free(sigbuf); /* Nothing confidential in the buffer */
+	}
+
+	encrypt_packet();
+	TRACE(("leave send_msg_userauth_pubkey"))
+}
+
+int cli_auth_pubkey() {
+
+	TRACE(("enter cli_auth_pubkey"))
+
+	if (cli_opts.privkeys != NULL) {
+		/* Send a trial request */
+		send_msg_userauth_pubkey(cli_opts.privkeys->key,
+				cli_opts.privkeys->type, 0);
+		cli_ses.lastprivkey = cli_opts.privkeys;
+		TRACE(("leave cli_auth_pubkey-success"))
+		return 1;
+	} else {
+		TRACE(("leave cli_auth_pubkey-failure"))
+		return 0;
+	}
+}
+#endif /* Pubkey auth */