view auth.h @ 1306:34e6127ef02e

merge fixes from PuTTY import.c toint() from misc.c (revids are from hggit conversion) changeset: 4620:60a336a6c85c user: Simon Tatham <[email protected]> date: Thu Feb 25 20:26:33 2016 +0000 files: import.c description: Fix potential segfaults in reading OpenSSH's ASN.1 key format. The length coming back from ber_read_id_len might have overflowed, so treat it as potentially negative. Also, while I'm here, accumulate it inside ber_read_id_len as an unsigned, so as to avoid undefined behaviour on integer overflow, and toint() it before return. Thanks to Hanno Böck for spotting this, with the aid of AFL. (cherry picked from commit 5b7833cd474a24ec098654dcba8cb9509f3bf2c1) Conflicts: import.c (cherry-picker's note: resolving the conflict involved removing an entire section of the original commit which fixed ECDSA code not present on this branch) changeset: 4619:9c6c638d98d8 user: Simon Tatham <[email protected]> date: Sun Jul 14 10:45:54 2013 +0000 files: import.c ssh.c sshdss.c sshpubk.c sshrsa.c description: Tighten up a lot of casts from unsigned to int which are read by one of the GET_32BIT macros and then used as length fields. Missing bounds checks against zero have been added, and also I've introduced a helper function toint() which casts from unsigned to int in such a way as to avoid C undefined behaviour, since I'm not sure I trust compilers any more to do the obviously sensible thing. [originally from svn r9918] changeset: 4618:3957829f24d3 user: Simon Tatham <[email protected]> date: Mon Jul 08 22:36:04 2013 +0000 files: import.c sshdss.c sshrsa.c description: Add an assortment of extra safety checks. [originally from svn r9896] changeset: 4617:2cddee0bce12 user: Jacob Nevins <[email protected]> date: Wed Dec 07 00:24:45 2005 +0000 files: import.c description: Institutional failure to memset() things pointed at rather than pointers. Things should now be zeroed and memory not leaked. Spotted by Brant Thomsen. [originally from svn r6476] changeset: 4616:24ac78a9c71d user: Simon Tatham <[email protected]> date: Wed Feb 11 13:58:27 2004 +0000 files: import.c description: Jacob's last-minute testing found a couple of trivial bugs in import.c, and my attempts to reproduce them in cmdgen found another one there :-) [originally from svn r3847] changeset: 4615:088d39a73db0 user: Simon Tatham <[email protected]> date: Thu Jan 22 18:52:49 2004 +0000 files: import.c description: Placate some gcc warnings. [originally from svn r3761] changeset: 4614:e4288bad4d93 parent: 1758:108b8924593d user: Simon Tatham <[email protected]> date: Fri Oct 03 21:21:23 2003 +0000 files: import.c description: My ASN.1 decoder returned wrong IDs for anything above 0x1E! Good job it's never had to yet. Ahem. [originally from svn r3479]
author Matt Johnston <matt@ucc.asn.au>
date Tue, 12 Jul 2016 23:00:01 +0800
parents 9169e4e7cbee
children 750ec4ec4cbe
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/*
 * Dropbear - a SSH2 server
 * 
 * Copyright (c) 2002,2003 Matt Johnston
 * 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. */

#ifndef DROPBEAR_AUTH_H_
#define DROPBEAR_AUTH_H_

#include "includes.h"
#include "signkey.h"
#include "chansession.h"

void svr_authinitialise(void);
void cli_authinitialise(void);

/* Server functions */
void recv_msg_userauth_request(void);
void send_msg_userauth_failure(int partial, int incrfail);
void send_msg_userauth_success(void);
void send_msg_userauth_banner(buffer *msg);
void svr_auth_password(void);
void svr_auth_pubkey(void);
void svr_auth_pam(void);

#ifdef ENABLE_SVR_PUBKEY_OPTIONS
int svr_pubkey_allows_agentfwd(void);
int svr_pubkey_allows_tcpfwd(void);
int svr_pubkey_allows_x11fwd(void);
int svr_pubkey_allows_pty(void);
void svr_pubkey_set_forced_command(struct ChanSess *chansess);
void svr_pubkey_options_cleanup(void);
int svr_add_pubkey_options(buffer *options_buf, int line_num, const char* filename);
#else
/* no option : success */
#define svr_pubkey_allows_agentfwd() 1
#define svr_pubkey_allows_tcpfwd() 1
#define svr_pubkey_allows_x11fwd() 1
#define svr_pubkey_allows_pty() 1
static inline void svr_pubkey_set_forced_command(struct ChanSess *chansess) { }
static inline void svr_pubkey_options_cleanup(void) { }
#define svr_add_pubkey_options(x,y,z) DROPBEAR_SUCCESS
#endif

/* Client functions */
void recv_msg_userauth_failure(void);
void recv_msg_userauth_success(void);
void recv_msg_userauth_specific_60(void);
void recv_msg_userauth_pk_ok(void);
void recv_msg_userauth_info_request(void);
void cli_get_user(void);
void cli_auth_getmethods(void);
int cli_auth_try(void);
void recv_msg_userauth_banner(void);
void cli_pubkeyfail(void);
void cli_auth_password(void);
int cli_auth_pubkey(void);
void cli_auth_interactive(void);
char* getpass_or_cancel(char* prompt);
void cli_auth_pubkey_cleanup(void);


#define MAX_USERNAME_LEN 25 /* arbitrary for the moment */

#define AUTH_TYPE_NONE      1
#define AUTH_TYPE_PUBKEY    (1 << 1)
#define AUTH_TYPE_PASSWORD  (1 << 2)
#define AUTH_TYPE_INTERACT  (1 << 3)

#define AUTH_METHOD_NONE "none"
#define AUTH_METHOD_NONE_LEN 4
#define AUTH_METHOD_PUBKEY "publickey"
#define AUTH_METHOD_PUBKEY_LEN 9
#define AUTH_METHOD_PASSWORD "password"
#define AUTH_METHOD_PASSWORD_LEN 8
#define AUTH_METHOD_INTERACT "keyboard-interactive"
#define AUTH_METHOD_INTERACT_LEN 20



/* This structure is shared between server and client - it contains
 * relatively little extraneous bits when used for the client rather than the
 * server */
struct AuthState {
	char *username; /* This is the username the client presents to check. It
					   is updated each run through, used for auth checking */
	unsigned char authtypes; /* Flags indicating which auth types are still 
								valid */
	unsigned int failcount; /* Number of (failed) authentication attempts.*/
	unsigned authdone : 1; /* 0 if we haven't authed, 1 if we have. Applies for
							  client and server (though has differing 
							  meanings). */
	unsigned perm_warn : 1; /* Server only, set if bad permissions on 
							   ~/.ssh/authorized_keys have already been
							   logged. */

	/* These are only used for the server */
	uid_t pw_uid;
	gid_t pw_gid;
	char *pw_dir;
	char *pw_shell;
	char *pw_name;
	char *pw_passwd;
#ifdef ENABLE_SVR_PUBKEY_OPTIONS
	struct PubKeyOptions* pubkey_options;
#endif
};

#ifdef ENABLE_SVR_PUBKEY_OPTIONS
struct PubKeyOptions;
struct PubKeyOptions {
	/* Flags */
	int no_port_forwarding_flag;
	int no_agent_forwarding_flag;
	int no_x11_forwarding_flag;
	int no_pty_flag;
	/* "command=" option. */
	char * forced_command;
};
#endif

#endif /* DROPBEAR_AUTH_H_ */