diff options
| -rw-r--r-- | options.h | 327 |
1 files changed, 327 insertions, 0 deletions
diff --git a/options.h b/options.h new file mode 100644 index 0000000..f43d0e0 --- /dev/null +++ b/options.h @@ -0,0 +1,327 @@ +/* Dropbear SSH + * Copyright (c) 2002,2003 Matt Johnston + * All rights reserved. See LICENSE for the license. */ + +#ifndef _OPTIONS_H_ +#define _OPTIONS_H_ + +/* Define compile-time options below - the "#ifndef DROPBEAR_XXX .... #endif" + * parts are to allow for commandline -DDROPBEAR_XXX options etc. */ + +/* IMPORTANT: Many options will require "make clean" after changes */ + +#ifndef DROPBEAR_DEFPORT +#define DROPBEAR_DEFPORT "22" +#endif + +#ifndef DROPBEAR_DEFADDRESS +/* Listen on all interfaces */ +#define DROPBEAR_DEFADDRESS "" +#endif + +/* Default hostkey paths - these can be specified on the command line */ +#ifndef DSS_PRIV_FILENAME +#define DSS_PRIV_FILENAME "/etc/dropbear/dropbear_dss_host_key" +#endif +#ifndef RSA_PRIV_FILENAME +#define RSA_PRIV_FILENAME "/etc/dropbear/dropbear_rsa_host_key" +#endif +#ifndef ECDSA_PRIV_FILENAME +#define ECDSA_PRIV_FILENAME "/etc/dropbear/dropbear_ecdsa_host_key" +#endif + +/* Set NON_INETD_MODE if you require daemon functionality (ie Dropbear listens + * on chosen ports and keeps accepting connections. This is the default. + * + * Set INETD_MODE if you want to be able to run Dropbear with inetd (or + * similar), where it will use stdin/stdout for connections, and each process + * lasts for a single connection. Dropbear should be invoked with the -i flag + * for inetd, and can only accept IPv4 connections. + * + * Both of these flags can be defined at once, don't compile without at least + * one of them. */ +#define NON_INETD_MODE +/*#define INETD_MODE*/ + +/* Setting this disables the fast exptmod bignum code. It saves ~5kB, but is + * perhaps 20% slower for pubkey operations (it is probably worth experimenting + * if you want to use this) */ +/*#define NO_FAST_EXPTMOD*/ + +/* Set this if you want to use the DROPBEAR_SMALL_CODE option. This can save +several kB in binary size however will make the symmetrical ciphers and hashes +slower, perhaps by 50%. Recommended for small systems that aren't doing +much traffic. */ +#define DROPBEAR_SMALL_CODE + +/* Enable X11 Forwarding - server only */ +/*#define ENABLE_X11FWD*/ + +/* Enable TCP Fowarding */ +/* 'Local' is "-L" style (client listening port forwarded via server) + * 'Remote' is "-R" style (server listening port forwarded via client) */ + +#define ENABLE_CLI_LOCALTCPFWD +#define ENABLE_CLI_REMOTETCPFWD + +#define ENABLE_SVR_LOCALTCPFWD +#define ENABLE_SVR_REMOTETCPFWD + +/* Enable Authentication Agent Forwarding */ +#define ENABLE_SVR_AGENTFWD +#define ENABLE_CLI_AGENTFWD + + +/* Note: Both ENABLE_CLI_PROXYCMD and ENABLE_CLI_NETCAT must be set to + * allow multihop dbclient connections */ + +/* Allow using -J <proxycommand> to run the connection through a + pipe to a program, rather the normal TCP connection */ +#define ENABLE_CLI_PROXYCMD + +/* Enable "Netcat mode" option. This will forward standard input/output + * to a remote TCP-forwarded connection */ +/*#define ENABLE_CLI_NETCAT*/ + +/* Whether to support "-c" and "-m" flags to choose ciphers/MACs at runtime */ +#define ENABLE_USER_ALGO_LIST + +/* Encryption - at least one required. + * Protocol RFC requires 3DES and recommends AES128 for interoperability. + * Including multiple keysize variants the same cipher + * (eg AES256 as well as AES128) will result in a minimal size increase.*/ +#define DROPBEAR_AES128 +#define DROPBEAR_3DES +#define DROPBEAR_AES256 +/* Compiling in Blowfish will add ~6kB to runtime heap memory usage */ +/*#define DROPBEAR_BLOWFISH*/ +/*#define DROPBEAR_TWOFISH256*/ +/*#define DROPBEAR_TWOFISH128*/ + +/* Enable "Counter Mode" for ciphers. This is more secure than normal + * CBC mode against certain attacks. This adds around 1kB to binary + * size and is recommended for most cases */ +#define DROPBEAR_ENABLE_CTR_MODE + +/* You can compile with no encryption if you want. In some circumstances + * this could be safe security-wise, though make sure you know what + * you're doing. Anyone can see everything that goes over the wire, so + * the only safe auth method is public key. */ +/* #define DROPBEAR_NONE_CIPHER */ + +/* Message Integrity - at least one required. + * Protocol RFC requires sha1 and recommends sha1-96. + * sha1-96 is of use for slow links as it has a smaller overhead. + * + * There's no reason to disable sha1 or sha1-96 to save space since it's + * used for the random number generator and public-key cryptography anyway. + * Disabling it here will just stop it from being used as the integrity portion + * of the ssh protocol. + * + * These hashes are also used for public key fingerprints in logs. + * If you disable MD5, Dropbear will fall back to SHA1 fingerprints, + * which are not the standard form. */ +#define DROPBEAR_SHA1_HMAC +#define DROPBEAR_SHA1_96_HMAC +/*#define DROPBEAR_SHA2_256_HMAC*/ +/*#define DROPBEAR_SHA2_512_HMAC*/ +#define DROPBEAR_MD5_HMAC + +/* You can also disable integrity. Don't bother disabling this if you're + * still using a cipher, it's relatively cheap. If you disable this it's dead + * simple for an attacker to run arbitrary commands on the remote host. Beware. */ +/* #define DROPBEAR_NONE_INTEGRITY */ + +/* Hostkey/public key algorithms - at least one required, these are used + * for hostkey as well as for verifying signatures with pubkey auth. + * Removing either of these won't save very much space. + * SSH2 RFC Draft requires dss, recommends rsa */ +#define DROPBEAR_RSA +#define DROPBEAR_DSS +/* ECDSA is significantly faster than RSA or DSS. Compiling in ECC + * code (either ECDSA or ECDH) increases binary size - around 30kB + * on x86-64 */ +#define DROPBEAR_ECDSA + +/* Generate hostkeys as-needed when the first connection using that key type occurs. + This avoids the need to otherwise run "dropbearkey" and avoids some problems + with badly seeded /dev/urandom when systems first boot. + This also requires a runtime flag "-R". This adds ~4kB to binary size (or hardly + anything if dropbearkey is linked in a "dropbearmulti" binary) */ +#define DROPBEAR_DELAY_HOSTKEY + +/* Enable Curve25519 for key exchange. This is another elliptic + * curve method with good security properties. Increases binary size + * by ~8kB on x86-64 */ +#define DROPBEAR_CURVE25519 + +/* Enable elliptic curve Diffie Hellman key exchange, see note about + * ECDSA above */ +#define DROPBEAR_ECDH + +/* Control the memory/performance/compression tradeoff for zlib. + * Set windowBits=8 for least memory usage, see your system's + * zlib.h for full details. + * Default settings (windowBits=15) will use 256kB for compression + * windowBits=8 will use 129kB for compression. + * Both modes will use ~35kB for decompression (using windowBits=15 for + * interoperability) */ +#ifndef DROPBEAR_ZLIB_WINDOW_BITS +#define DROPBEAR_ZLIB_WINDOW_BITS 15 +#endif + +/* Whether to do reverse DNS lookups. */ +/*#define DO_HOST_LOOKUP */ + +/* Whether to print the message of the day (MOTD). This doesn't add much code + * size */ +#define DO_MOTD + +/* The MOTD file path */ +#ifndef MOTD_FILENAME +#define MOTD_FILENAME "/etc/motd" +#endif + +/* Authentication Types - at least one required. + RFC Draft requires pubkey auth, and recommends password */ + +/* Note: PAM auth is quite simple and only works for PAM modules which just do + * a simple "Login: " "Password: " (you can edit the strings in svr-authpam.c). + * It's useful for systems like OS X where standard password crypts don't work + * but there's an interface via a PAM module. It won't work for more complex + * PAM challenge/response. + * You can't enable both PASSWORD and PAM. */ + +#define ENABLE_SVR_PASSWORD_AUTH +/* PAM requires ./configure --enable-pam */ +/*#define ENABLE_SVR_PAM_AUTH */ +#define ENABLE_SVR_PUBKEY_AUTH + +/* Whether to take public key options in + * authorized_keys file into account */ +#ifdef ENABLE_SVR_PUBKEY_AUTH +#define ENABLE_SVR_PUBKEY_OPTIONS +#endif + +#define ENABLE_CLI_PASSWORD_AUTH +#define ENABLE_CLI_PUBKEY_AUTH +#define ENABLE_CLI_INTERACT_AUTH + +/* This variable can be used to set a password for client + * authentication on the commandline. Beware of platforms + * that don't protect environment variables of processes etc. Also + * note that it will be provided for all "hidden" client-interactive + * style prompts - if you want something more sophisticated, use + * SSH_ASKPASS instead. Comment out this var to remove this functionality.*/ +#define DROPBEAR_PASSWORD_ENV "DROPBEAR_PASSWORD" + +/* Define this (as well as ENABLE_CLI_PASSWORD_AUTH) to allow the use of + * a helper program for the ssh client. The helper program should be + * specified in the SSH_ASKPASS environment variable, and dbclient + * should be run with DISPLAY set and no tty. The program should + * return the password on standard output */ +/*#define ENABLE_CLI_ASKPASS_HELPER*/ + +/* Save a network roundtrip by sendng a real auth request immediately after + * sending a query for the available methods. It is at the expense of < 100 + * bytes of extra network traffic. This is not yet enabled by default since it + * could cause problems with non-compliant servers */ +/* #define DROPBEAR_CLI_IMMEDIATE_AUTH */ + +/* Source for randomness. This must be able to provide hundreds of bytes per SSH + * connection without blocking. In addition /dev/random is used for seeding + * rsa/dss key generation */ +#define DROPBEAR_URANDOM_DEV "/dev/urandom" + +/* Set this to use PRNGD or EGD instead of /dev/urandom or /dev/random */ +/*#define DROPBEAR_PRNGD_SOCKET "/var/run/dropbear-rng"*/ + + +/* Specify the number of clients we will allow to be connected but + * not yet authenticated. After this limit, connections are rejected */ +/* The first setting is per-IP, to avoid denial of service */ +#ifndef MAX_UNAUTH_PER_IP +#define MAX_UNAUTH_PER_IP 5 +#endif + +/* And then a global limit to avoid chewing memory if connections + * come from many IPs */ +#ifndef MAX_UNAUTH_CLIENTS +#define MAX_UNAUTH_CLIENTS 30 +#endif + +/* Maximum number of failed authentication tries (server option) */ +#ifndef MAX_AUTH_TRIES +#define MAX_AUTH_TRIES 10 +#endif + +/* The default file to store the daemon's process ID, for shutdown + scripts etc. This can be overridden with the -P flag */ +#ifndef DROPBEAR_PIDFILE +#define DROPBEAR_PIDFILE "/var/run/dropbear.pid" +#endif + +/* The command to invoke for xauth when using X11 forwarding. + * "-q" for quiet */ +#ifndef XAUTH_COMMAND +/*#define XAUTH_COMMAND "/usr/bin/xauth -q"*/ +#endif + +/* if you want to enable running an sftp server (such as the one included with + * OpenSSH), set the path below. If the path isn't defined, sftp will not + * be enabled */ +#ifndef SFTPSERVER_PATH +/*#define SFTPSERVER_PATH "/usr/libexec/sftp-server"*/ +#endif + +/* This is used by the scp binary when used as a client binary. If you're + * not using the Dropbear client, you'll need to change it */ +#define _PATH_SSH_PROGRAM "/usr/bin/dbclient" + +/* Whether to log commands executed by a client. This only logs the + * (single) command sent to the server, not what a user did in a + * shell/sftp session etc. */ +/* #define LOG_COMMANDS */ + +/* Window size limits. These tend to be a trade-off between memory + usage and network performance: */ +/* Size of the network receive window. This amount of memory is allocated + as a per-channel receive buffer. Increasing this value can make a + significant difference to network performance. 24kB was empirically + chosen for a 100mbit ethernet network. The value can be altered at + runtime with the -W argument. */ +#ifndef DEFAULT_RECV_WINDOW +#define DEFAULT_RECV_WINDOW 24576 +#endif +/* Maximum size of a received SSH data packet - this _MUST_ be >= 32768 + in order to interoperate with other implementations */ +#ifndef RECV_MAX_PAYLOAD_LEN +#define RECV_MAX_PAYLOAD_LEN 32768 +#endif +/* Maximum size of a transmitted data packet - this can be any value, + though increasing it may not make a significant difference. */ +#ifndef TRANS_MAX_PAYLOAD_LEN +#define TRANS_MAX_PAYLOAD_LEN 16384 +#endif + +/* Ensure that data is transmitted every KEEPALIVE seconds. This can +be overridden at runtime with -K. 0 disables keepalives */ +#define DEFAULT_KEEPALIVE 0 + +/* If this many KEEPALIVES are sent with no packets received from the +other side, exit. Not run-time configurable - if you have a need +for runtime configuration please mail the Dropbear list */ +#define DEFAULT_KEEPALIVE_LIMIT 3 + +/* Ensure that data is received within IDLE_TIMEOUT seconds. This can +be overridden at runtime with -I. 0 disables idle timeouts */ +#define DEFAULT_IDLE_TIMEOUT 0 + +/* The default path. This will often get replaced by the shell */ +#define DEFAULT_PATH "/usr/bin:/bin" + +/* Some other defines (that mostly should be left alone) are defined + * in sysoptions.h */ +#include "sysoptions.h" + +#endif /* _OPTIONS_H_ */ |