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/*******************************************************************
* 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 "2013.60"
#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 1024 /* 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_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 */
#define LTM_DESC
#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
// hashes which will be linked and registered
#if defined(DROPBEAR_SHA2_256_HMAC) || defined(DROPBEAR_ECC_256)
#define DROPBEAR_SHA256
#endif
#if defined(DROPBEAR_ECC_384)
#define DROPBEAR_SHA384
#endif
#if defined(DROPBEAR_SHA2_512_HMAC) || defined(DROPBEAR_ECC_521)
#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 1400 /* ~= MAX_PROPOSED_ALGO * MAX_NAME_LEN, also
is the max length for a password etc */
/* 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 */
/* no include guard for this file */
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