| /* Dropbear SSH |
| * Copyright (c) 2002,2003 Matt Johnston |
| * All rights reserved. See LICENSE for the license. */ |
| |
| #ifndef DROPBEAR_OPTIONS_H_ |
| #define DROPBEAR_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 CBC mode for ciphers. This has security issues though |
| * is the most compatible with older SSH implementations */ |
| #define DROPBEAR_ENABLE_CBC_MODE |
| |
| /* Enable "Counter Mode" for ciphers. This is more secure than normal |
| * CBC mode against certain attacks. It is recommended for security |
| * and forwards compatibility */ |
| #define DROPBEAR_ENABLE_CTR_MODE |
| |
| /* Twofish counter mode is disabled by default because it |
| has not been tested for interoperability with other SSH implementations. |
| If you test it please contact the Dropbear author */ |
| /* #define DROPBEAR_TWOFISH_CTR */ |
| |
| /* 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 |
| |
| /* Key exchange algorithm. |
| * group14_sha1 - 2048 bit, sha1 |
| * group14_sha256 - 2048 bit, sha2-256 |
| * group16 - 4096 bit, sha2-512 |
| * group1 - 1024 bit, sha1 |
| * |
| * group14 is supported by most implementations. |
| * group16 provides a greater strength level but is slower and increases binary size |
| * group1 is too small for security though is necessary if you need |
| compatibility with some implementations such as Dropbear versions < 0.53 |
| */ |
| #define DROPBEAR_DH_GROUP1 1 |
| #define DROPBEAR_DH_GROUP14_SHA1 1 |
| #define DROPBEAR_DH_GROUP14_SHA256 1 |
| #define DROPBEAR_DH_GROUP16 0 |
| |
| /* 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 |
| |
| /* Server won't allow zlib compression until after authentication. Prevents |
| flaws in the zlib library being unauthenticated exploitable flaws. |
| Some old ssh clients may not support the alternative zlib@openssh.com method */ |
| #define DROPBEAR_SERVER_DELAY_ZLIB 1 |
| |
| /* 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. */ |
| |
| /* This requires crypt() */ |
| #ifdef HAVE_CRYPT |
| #define ENABLE_SVR_PASSWORD_AUTH |
| #endif |
| /* 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 |
| |
| /* This requires getpass. */ |
| #ifdef HAVE_GETPASS |
| #define ENABLE_CLI_PASSWORD_AUTH |
| #define ENABLE_CLI_INTERACT_AUTH |
| #endif |
| #define ENABLE_CLI_PUBKEY_AUTH |
| |
| /* A default argument for dbclient -i <privatekey>. |
| Homedir is prepended unless path begins with / */ |
| #define DROPBEAR_DEFAULT_CLI_AUTHKEY ".ssh/id_dropbear" |
| |
| /* 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 DROPBEAR_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 /* DROPBEAR_OPTIONS_H_ */ |
