/******************************************************************* * 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 "2015.71" #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 1000 /* 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 "keepalive@openssh.com" /* 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 */