view sysoptions.h @ 1156:a8f4dade70e5

avoid getpass when not used some systems (like android's bionic) do not provide getpass. you can disable ENABLE_CLI_PASSWORD_AUTH & ENABLE_CLI_INTERACT_AUTH to avoid its use (and rely on pubkey auth), but the link still fails because the support file calls getpass. do not define this func if both of those auth methods are not used.
author Mike Frysinger <vapier@gentoo.org>
date Wed, 21 Oct 2015 22:39:55 +0800
parents 809feaa9408f
children 41a5820cab8b
line wrap: on
line source

/*******************************************************************
 * You shouldn't edit this file unless you know you need to. 
 * This file is only included from options.h
 *******************************************************************/

#ifndef DROPBEAR_VERSION
#define DROPBEAR_VERSION "2015.68"
#endif

#define LOCAL_IDENT "SSH-2.0-dropbear_" DROPBEAR_VERSION
#define PROGNAME "dropbear"

/* Spec recommends after one hour or 1 gigabyte of data. One hour
 * is a bit too verbose, so we try 8 hours */
#ifndef KEX_REKEY_TIMEOUT
#define KEX_REKEY_TIMEOUT (3600 * 8)
#endif
#ifndef KEX_REKEY_DATA
#define KEX_REKEY_DATA (1<<30) /* 2^30 == 1GB, this value must be < INT_MAX */
#endif
/* Close connections to clients which haven't authorised after AUTH_TIMEOUT */
#ifndef AUTH_TIMEOUT
#define AUTH_TIMEOUT 300 /* we choose 5 minutes */
#endif

/* A client should try and send an initial key exchange packet guessing
 * the algorithm that will match - saves a round trip connecting, has little
 * overhead if the guess was "wrong". */
#define USE_KEX_FIRST_FOLLOWS
/* Use protocol extension to allow "first follows" to succeed more frequently.
 * This is currently Dropbear-specific but will gracefully fallback when connecting
 * to other implementations. */
#define USE_KEXGUESS2

/* Minimum key sizes for DSS and RSA */
#ifndef MIN_DSS_KEYLEN
#define MIN_DSS_KEYLEN 512
#endif
#ifndef MIN_RSA_KEYLEN
#define MIN_RSA_KEYLEN 512
#endif

#define MAX_BANNER_SIZE 2000 /* this is 25*80 chars, any more is foolish */
#define MAX_BANNER_LINES 20 /* How many lines the client will display */

/* the number of NAME=VALUE pairs to malloc for environ, if we don't have
 * the clearenv() function */
#define ENV_SIZE 100

#define MAX_CMD_LEN 9000 /* max length of a command */
#define MAX_TERM_LEN 200 /* max length of TERM name */

#define MAX_HOST_LEN 254 /* max hostname len for tcp fwding */
#define MAX_IP_LEN 15 /* strlen("255.255.255.255") == 15 */

#define DROPBEAR_MAX_PORTS 10 /* max number of ports which can be specified,
								 ipv4 and ipv6 don't count twice */

/* Each port might have at least a v4 and a v6 address */
#define MAX_LISTEN_ADDR (DROPBEAR_MAX_PORTS*3)

#define _PATH_TTY "/dev/tty"

#define _PATH_CP "/bin/cp"

#define DROPBEAR_ESCAPE_CHAR '~'

/* success/failure defines */
#define DROPBEAR_SUCCESS 0
#define DROPBEAR_FAILURE -1

/* Required for pubkey auth */
#if defined(ENABLE_SVR_PUBKEY_AUTH) || defined(DROPBEAR_CLIENT)
#define DROPBEAR_SIGNKEY_VERIFY
#endif

#define SHA1_HASH_SIZE 20
#define MD5_HASH_SIZE 16
#define MAX_HASH_SIZE 64 /* sha512 */

#define MAX_KEY_LEN 32 /* 256 bits for aes256 etc */
#define MAX_IV_LEN 20 /* must be same as max blocksize,  */

#if defined(DROPBEAR_SHA2_512_HMAC)
#define MAX_MAC_LEN 64
#elif defined(DROPBEAR_SHA2_256_HMAC)
#define MAX_MAC_LEN 32
#else
#define MAX_MAC_LEN 20
#endif

#if defined(DROPBEAR_ECDH) || defined (DROPBEAR_ECDSA)
#define DROPBEAR_ECC
/* Debian doesn't define this in system headers */
#ifndef LTM_DESC
#define LTM_DESC
#endif
#endif

#ifdef DROPBEAR_ECC
#define DROPBEAR_ECC_256
#define DROPBEAR_ECC_384
#define DROPBEAR_ECC_521
#endif

#ifdef DROPBEAR_ECC
#define DROPBEAR_LTC_PRNG
#endif

/* RSA can be vulnerable to timing attacks which use the time required for
 * signing to guess the private key. Blinding avoids this attack, though makes
 * signing operations slightly slower. */
#define RSA_BLINDING

/* hashes which will be linked and registered */
#if defined(DROPBEAR_SHA2_256_HMAC) || defined(DROPBEAR_ECC_256) || defined(DROPBEAR_CURVE25519)
#define DROPBEAR_SHA256
#endif
#if defined(DROPBEAR_ECC_384)
#define DROPBEAR_SHA384
#endif
/* LTC SHA384 depends on SHA512 */
#if defined(DROPBEAR_SHA2_512_HMAC) || defined(DROPBEAR_ECC_521) || defined(DROPBEAR_ECC_384)
#define DROPBEAR_SHA512
#endif
#if defined(DROPBEAR_MD5_HMAC)
#define DROPBEAR_MD5
#endif

/* roughly 2x 521 bits */
#define MAX_ECC_SIZE 140

#define MAX_NAME_LEN 64 /* maximum length of a protocol name, isn't
						   explicitly specified for all protocols (just
						   for algos) but seems valid */

#define MAX_PROPOSED_ALGO 20

/* size/count limits */
/* From transport rfc */
#define MIN_PACKET_LEN 16

#define RECV_MAX_PACKET_LEN (MAX(35000, ((RECV_MAX_PAYLOAD_LEN)+100)))

/* for channel code */
#define TRANS_MAX_WINDOW 500000000 /* 500MB is sufficient, stopping overflow */
#define TRANS_MAX_WIN_INCR 500000000 /* overflow prevention */

#define RECV_WINDOWEXTEND (opts.recv_window / 3) /* We send a "window extend" every
								RECV_WINDOWEXTEND bytes */
#define MAX_RECV_WINDOW (1024*1024) /* 1 MB should be enough */

#define MAX_CHANNELS 100 /* simple mem restriction, includes each tcp/x11
							connection, so can't be _too_ small */

#define MAX_STRING_LEN (MAX(MAX_CMD_LEN, 2400)) /* Sun SSH needs 2400 for algos,
                                                   MAX_CMD_LEN is usually longer */

/* For a 4096 bit DSS key, empirically determined */
#define MAX_PUBKEY_SIZE 1700
/* For a 4096 bit DSS key, empirically determined */
#define MAX_PRIVKEY_SIZE 1700

#define MAX_HOSTKEYS 3

/* The maximum size of the bignum portion of the kexhash buffer */
/* Sect. 8 of the transport rfc 4253, K_S + e + f + K */
#define KEXHASHBUF_MAX_INTS (1700 + 130 + 130 + 130)

#define DROPBEAR_MAX_SOCKS 2 /* IPv4, IPv6 are all we'll get for now. Revisit
								in a few years time.... */

#define DROPBEAR_MAX_CLI_PASS 1024

#define DROPBEAR_MAX_CLI_INTERACT_PROMPTS 80 /* The number of prompts we'll 
												accept for keyb-interactive
												auth */


#if defined(DROPBEAR_AES256) || defined(DROPBEAR_AES128)
#define DROPBEAR_AES
#endif

#if defined(DROPBEAR_TWOFISH256) || defined(DROPBEAR_TWOFISH128)
#define DROPBEAR_TWOFISH
#endif

#ifndef ENABLE_X11FWD
#define DISABLE_X11FWD
#endif

#if defined(ENABLE_CLI_REMOTETCPFWD) || defined(ENABLE_CLI_LOCALTCPFWD)
#define ENABLE_CLI_ANYTCPFWD 
#endif

#if defined(ENABLE_CLI_LOCALTCPFWD) || defined(ENABLE_SVR_REMOTETCPFWD)
#define DROPBEAR_TCP_ACCEPT
#endif

#if defined(ENABLE_CLI_REMOTETCPFWD) || defined(ENABLE_CLI_LOCALTCPFWD) || \
	defined(ENABLE_SVR_REMOTETCPFWD) || defined(ENABLE_SVR_LOCALTCPFWD) || \
	defined(ENABLE_SVR_AGENTFWD) || defined(ENABLE_X11FWD)
#define USING_LISTENERS
#endif

#if defined(ENABLE_CLI_NETCAT) && defined(ENABLE_CLI_PROXYCMD)
#define ENABLE_CLI_MULTIHOP
#endif

#if defined(ENABLE_CLI_AGENTFWD) || defined(DROPBEAR_PRNGD_SOCKET)
#define ENABLE_CONNECT_UNIX
#endif

#if defined(DROPBEAR_CLIENT) || defined(ENABLE_SVR_PUBKEY_AUTH)
#define DROPBEAR_KEY_LINES /* ie we're using authorized_keys or known_hosts */
#endif

/* Changing this is inadvisable, it appears to have problems
 * with flushing compressed data */
#define DROPBEAR_ZLIB_MEM_LEVEL 8

#if defined(ENABLE_SVR_PASSWORD_AUTH) && defined(ENABLE_SVR_PAM_AUTH)
#error "You can't turn on PASSWORD and PAM auth both at once. Fix it in options.h"
#endif

/* We use dropbear_client and dropbear_server as shortcuts to avoid redundant
 * code, if we're just compiling as client or server */
#if defined(DROPBEAR_SERVER) && defined(DROPBEAR_CLIENT)

#define IS_DROPBEAR_SERVER (ses.isserver == 1)
#define IS_DROPBEAR_CLIENT (ses.isserver == 0)

#elif defined(DROPBEAR_SERVER)

#define IS_DROPBEAR_SERVER 1
#define IS_DROPBEAR_CLIENT 0

#elif defined(DROPBEAR_CLIENT)

#define IS_DROPBEAR_SERVER 0
#define IS_DROPBEAR_CLIENT 1

#else
/* Just building key utils? */
#define IS_DROPBEAR_SERVER 0
#define IS_DROPBEAR_CLIENT 0

#endif /* neither DROPBEAR_SERVER nor DROPBEAR_CLIENT */

#ifndef HAVE_FORK
#define USE_VFORK
#endif  /* don't HAVE_FORK */

#if MAX_UNAUTH_CLIENTS > MAX_CHANNELS
#define DROPBEAR_LISTEN_BACKLOG MAX_UNAUTH_CLIENTS
#else
#define DROPBEAR_LISTEN_BACKLOG MAX_CHANNELS
#endif

/* free memory before exiting */
#define DROPBEAR_CLEANUP

/* Use this string since some implementations might special-case it */
#define DROPBEAR_KEEPALIVE_STRING "[email protected]"

/* Linux will attempt TCP fast open, falling back if not supported by the kernel.
 * Currently server is enabled but client is disabled by default until there
 * is further compatibility testing */
#ifdef __linux__
#define DROPBEAR_SERVER_TCP_FAST_OPEN
/* #define DROPBEAR_CLIENT_TCP_FAST_OPEN */
#endif

/* no include guard for this file */