packetstorm sync

1 files changed, 794 insertions, 0 deletions

diff --git a/other/openssh-2.1.1p4/readconf.c b/other/openssh-2.1.1p4/readconf.c
new file mode 100644
index 0000000..06cfaa1
--- /dev/null
+++ b/other/openssh-2.1.1p4/readconf.c
@@ -0,0 +1,794 @@
+/*
+ *
+ * readconf.c
+ *
+ * Author: Tatu Ylonen <ylo@cs.hut.fi>
+ *
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ *                    All rights reserved
+ *
+ * Created: Sat Apr 22 00:03:10 1995 ylo
+ *
+ * Functions for reading the configuration files.
+ *
+ */
+
+#include "includes.h"
+RCSID("$OpenBSD: readconf.c,v 1.43 2000/07/14 22:59:46 markus Exp $");
+
+#include "ssh.h"
+#include "cipher.h"
+#include "readconf.h"
+#include "match.h"
+#include "xmalloc.h"
+#include "compat.h"
+
+/* Format of the configuration file:
+
+   # Configuration data is parsed as follows:
+   #  1. command line options
+   #  2. user-specific file
+   #  3. system-wide file
+   # Any configuration value is only changed the first time it is set.
+   # Thus, host-specific definitions should be at the beginning of the
+   # configuration file, and defaults at the end.
+
+   # Host-specific declarations.  These may override anything above.  A single
+   # host may match multiple declarations; these are processed in the order
+   # that they are given in.
+
+   Host *.ngs.fi ngs.fi
+     FallBackToRsh no
+
+   Host fake.com
+     HostName another.host.name.real.org
+     User blaah
+     Port 34289
+     ForwardX11 no
+     ForwardAgent no
+
+   Host books.com
+     RemoteForward 9999 shadows.cs.hut.fi:9999
+     Cipher 3des
+
+   Host fascist.blob.com
+     Port 23123
+     User tylonen
+     RhostsAuthentication no
+     PasswordAuthentication no
+
+   Host puukko.hut.fi
+     User t35124p
+     ProxyCommand ssh-proxy %h %p
+
+   Host *.fr
+     UseRsh yes
+
+   Host *.su
+     Cipher none
+     PasswordAuthentication no
+
+   # Defaults for various options
+   Host *
+     ForwardAgent no
+     ForwardX11 yes
+     RhostsAuthentication yes
+     PasswordAuthentication yes
+     RSAAuthentication yes
+     RhostsRSAAuthentication yes
+     FallBackToRsh no
+     UseRsh no
+     StrictHostKeyChecking yes
+     KeepAlives no
+     IdentityFile ~/.ssh/identity
+     Port 22
+     EscapeChar ~
+
+*/
+
+/* Keyword tokens. */
+
+typedef enum {
+        oBadOption,
+        oForwardAgent, oForwardX11, oGatewayPorts, oRhostsAuthentication,
+        oPasswordAuthentication, oRSAAuthentication, oFallBackToRsh, oUseRsh,
+        oSkeyAuthentication, oXAuthLocation,
+#ifdef KRB4
+        oKerberosAuthentication,
+#endif /* KRB4 */
+#ifdef AFS
+        oKerberosTgtPassing, oAFSTokenPassing,
+#endif
+        oIdentityFile, oHostName, oPort, oCipher, oRemoteForward, oLocalForward,
+        oUser, oHost, oEscapeChar, oRhostsRSAAuthentication, oProxyCommand,
+        oGlobalKnownHostsFile, oUserKnownHostsFile, oConnectionAttempts,
+        oBatchMode, oCheckHostIP, oStrictHostKeyChecking, oCompression,
+        oCompressionLevel, oKeepAlives, oNumberOfPasswordPrompts, oTISAuthentication,
+        oUsePrivilegedPort, oLogLevel, oCiphers, oProtocol, oIdentityFile2,
+        oGlobalKnownHostsFile2, oUserKnownHostsFile2, oDSAAuthentication
+} OpCodes;
+
+/* Textual representations of the tokens. */
+
+static struct {
+        const char *name;
+        OpCodes opcode;
+} keywords[] = {
+        { "forwardagent", oForwardAgent },
+        { "forwardx11", oForwardX11 },
+        { "xauthlocation", oXAuthLocation },
+        { "gatewayports", oGatewayPorts },
+        { "useprivilegedport", oUsePrivilegedPort },
+        { "rhostsauthentication", oRhostsAuthentication },
+        { "passwordauthentication", oPasswordAuthentication },
+        { "rsaauthentication", oRSAAuthentication },
+        { "dsaauthentication", oDSAAuthentication },
+        { "skeyauthentication", oSkeyAuthentication },
+#ifdef KRB4
+        { "kerberosauthentication", oKerberosAuthentication },
+#endif /* KRB4 */
+#ifdef AFS
+        { "kerberostgtpassing", oKerberosTgtPassing },
+        { "afstokenpassing", oAFSTokenPassing },
+#endif
+        { "fallbacktorsh", oFallBackToRsh },
+        { "usersh", oUseRsh },
+        { "identityfile", oIdentityFile },
+        { "identityfile2", oIdentityFile2 },
+        { "hostname", oHostName },
+        { "proxycommand", oProxyCommand },
+        { "port", oPort },
+        { "cipher", oCipher },
+        { "ciphers", oCiphers },
+        { "protocol", oProtocol },
+        { "remoteforward", oRemoteForward },
+        { "localforward", oLocalForward },
+        { "user", oUser },
+        { "host", oHost },
+        { "escapechar", oEscapeChar },
+        { "rhostsrsaauthentication", oRhostsRSAAuthentication },
+        { "globalknownhostsfile", oGlobalKnownHostsFile },
+        { "userknownhostsfile", oUserKnownHostsFile },
+        { "globalknownhostsfile2", oGlobalKnownHostsFile2 },
+        { "userknownhostsfile2", oUserKnownHostsFile2 },
+        { "connectionattempts", oConnectionAttempts },
+        { "batchmode", oBatchMode },
+        { "checkhostip", oCheckHostIP },
+        { "stricthostkeychecking", oStrictHostKeyChecking },
+        { "compression", oCompression },
+        { "compressionlevel", oCompressionLevel },
+        { "keepalive", oKeepAlives },
+        { "numberofpasswordprompts", oNumberOfPasswordPrompts },
+        { "tisauthentication", oTISAuthentication },
+        { "loglevel", oLogLevel },
+        { NULL, 0 }
+};
+
+/*
+ * Adds a local TCP/IP port forward to options.  Never returns if there is an
+ * error.
+ */
+
+void
+add_local_forward(Options *options, u_short port, const char *host,
+                  u_short host_port)
+{
+        Forward *fwd;
+        extern uid_t original_real_uid;
+        if (port < IPPORT_RESERVED && original_real_uid != 0)
+                fatal("Privileged ports can only be forwarded by root.\n");
+        if (options->num_local_forwards >= SSH_MAX_FORWARDS_PER_DIRECTION)
+                fatal("Too many local forwards (max %d).", SSH_MAX_FORWARDS_PER_DIRECTION);
+        fwd = &options->local_forwards[options->num_local_forwards++];
+        fwd->port = port;
+        fwd->host = xstrdup(host);
+        fwd->host_port = host_port;
+}
+
+/*
+ * Adds a remote TCP/IP port forward to options.  Never returns if there is
+ * an error.
+ */
+
+void
+add_remote_forward(Options *options, u_short port, const char *host,
+                   u_short host_port)
+{
+        Forward *fwd;
+        if (options->num_remote_forwards >= SSH_MAX_FORWARDS_PER_DIRECTION)
+                fatal("Too many remote forwards (max %d).",
+                      SSH_MAX_FORWARDS_PER_DIRECTION);
+        fwd = &options->remote_forwards[options->num_remote_forwards++];
+        fwd->port = port;
+        fwd->host = xstrdup(host);
+        fwd->host_port = host_port;
+}
+
+/*
+ * Returns the number of the token pointed to by cp of length len. Never
+ * returns if the token is not known.
+ */
+
+static OpCodes
+parse_token(const char *cp, const char *filename, int linenum)
+{
+        unsigned int i;
+
+        for (i = 0; keywords[i].name; i++)
+                if (strcasecmp(cp, keywords[i].name) == 0)
+                        return keywords[i].opcode;
+
+        fprintf(stderr, "%s: line %d: Bad configuration option: %s\n",
+                filename, linenum, cp);
+        return oBadOption;
+}
+
+/*
+ * Processes a single option line as used in the configuration files. This
+ * only sets those values that have not already been set.
+ */
+
+int
+process_config_line(Options *options, const char *host,
+                    char *line, const char *filename, int linenum,
+                    int *activep)
+{
+        char buf[256], *s, *string, **charptr, *endofnumber, *keyword, *arg;
+        int opcode, *intptr, value;
+        u_short fwd_port, fwd_host_port;
+
+        s = line;
+        /* Get the keyword. (Each line is supposed to begin with a keyword). */
+        keyword = strdelim(&s);
+        /* Ignore leading whitespace. */
+        if (*keyword == '\0')
+                keyword = strdelim(&s);
+        if (!*keyword || *keyword == '\n' || *keyword == '#')
+                return 0;
+
+        opcode = parse_token(keyword, filename, linenum);
+
+        switch (opcode) {
+        case oBadOption:
+                /* don't panic, but count bad options */
+                return -1;
+                /* NOTREACHED */
+        case oForwardAgent:
+                intptr = &options->forward_agent;
+parse_flag:
+                arg = strdelim(&s);
+                if (!arg || *arg == '\0')
+                        fatal("%.200s line %d: Missing yes/no argument.", filename, linenum);
+                value = 0;      /* To avoid compiler warning... */
+                if (strcmp(arg, "yes") == 0 || strcmp(arg, "true") == 0)
+                        value = 1;
+                else if (strcmp(arg, "no") == 0 || strcmp(arg, "false") == 0)
+                        value = 0;
+                else
+                        fatal("%.200s line %d: Bad yes/no argument.", filename, linenum);
+                if (*activep && *intptr == -1)
+                        *intptr = value;
+                break;
+
+        case oForwardX11:
+                intptr = &options->forward_x11;
+                goto parse_flag;
+
+        case oGatewayPorts:
+                intptr = &options->gateway_ports;
+                goto parse_flag;
+
+        case oUsePrivilegedPort:
+                intptr = &options->use_privileged_port;
+                goto parse_flag;
+
+        case oRhostsAuthentication:
+                intptr = &options->rhosts_authentication;
+                goto parse_flag;
+
+        case oPasswordAuthentication:
+                intptr = &options->password_authentication;
+                goto parse_flag;
+
+        case oDSAAuthentication:
+                intptr = &options->dsa_authentication;
+                goto parse_flag;
+
+        case oRSAAuthentication:
+                intptr = &options->rsa_authentication;
+                goto parse_flag;
+
+        case oRhostsRSAAuthentication:
+                intptr = &options->rhosts_rsa_authentication;
+                goto parse_flag;
+
+        case oTISAuthentication:
+                /* fallthrough, there is no difference on the client side */
+        case oSkeyAuthentication:
+                intptr = &options->skey_authentication;
+                goto parse_flag;
+
+#ifdef KRB4
+        case oKerberosAuthentication:
+                intptr = &options->kerberos_authentication;
+                goto parse_flag;
+#endif /* KRB4 */
+
+#ifdef AFS
+        case oKerberosTgtPassing:
+                intptr = &options->kerberos_tgt_passing;
+                goto parse_flag;
+
+        case oAFSTokenPassing:
+                intptr = &options->afs_token_passing;
+                goto parse_flag;
+#endif
+
+        case oFallBackToRsh:
+                intptr = &options->fallback_to_rsh;
+                goto parse_flag;
+
+        case oUseRsh:
+                intptr = &options->use_rsh;
+                goto parse_flag;
+
+        case oBatchMode:
+                intptr = &options->batch_mode;
+                goto parse_flag;
+
+        case oCheckHostIP:
+                intptr = &options->check_host_ip;
+                goto parse_flag;
+
+        case oStrictHostKeyChecking:
+                intptr = &options->strict_host_key_checking;
+                arg = strdelim(&s);
+                if (!arg || *arg == '\0')
+                        fatal("%.200s line %d: Missing yes/no argument.",
+                              filename, linenum);
+                value = 0;      /* To avoid compiler warning... */
+                if (strcmp(arg, "yes") == 0 || strcmp(arg, "true") == 0)
+                        value = 1;
+                else if (strcmp(arg, "no") == 0 || strcmp(arg, "false") == 0)
+                        value = 0;
+                else if (strcmp(arg, "ask") == 0)
+                        value = 2;
+                else
+                        fatal("%.200s line %d: Bad yes/no/ask argument.", filename, linenum);
+                if (*activep && *intptr == -1)
+                        *intptr = value;
+                break;
+
+        case oCompression:
+                intptr = &options->compression;
+                goto parse_flag;
+
+        case oKeepAlives:
+                intptr = &options->keepalives;
+                goto parse_flag;
+
+        case oNumberOfPasswordPrompts:
+                intptr = &options->number_of_password_prompts;
+                goto parse_int;
+
+        case oCompressionLevel:
+                intptr = &options->compression_level;
+                goto parse_int;
+
+        case oIdentityFile:
+        case oIdentityFile2:
+                arg = strdelim(&s);
+                if (!arg || *arg == '\0')
+                        fatal("%.200s line %d: Missing argument.", filename, linenum);
+                if (*activep) {
+                        intptr = (opcode == oIdentityFile) ?
+                            &options->num_identity_files :
+                            &options->num_identity_files2;
+                        if (*intptr >= SSH_MAX_IDENTITY_FILES)
+                                fatal("%.200s line %d: Too many identity files specified (max %d).",
+                                      filename, linenum, SSH_MAX_IDENTITY_FILES);
+                        charptr = (opcode == oIdentityFile) ?
+                            &options->identity_files[*intptr] :
+                            &options->identity_files2[*intptr];
+                        *charptr = xstrdup(arg);
+                        *intptr = *intptr + 1;
+                }
+                break;
+
+        case oXAuthLocation:
+                charptr=&options->xauth_location;
+                goto parse_string;
+
+        case oUser:
+                charptr = &options->user;
+parse_string:
+                arg = strdelim(&s);
+                if (!arg || *arg == '\0')
+                        fatal("%.200s line %d: Missing argument.", filename, linenum);
+                if (*activep && *charptr == NULL)
+                        *charptr = xstrdup(arg);
+                break;
+
+        case oGlobalKnownHostsFile:
+                charptr = &options->system_hostfile;
+                goto parse_string;
+
+        case oUserKnownHostsFile:
+                charptr = &options->user_hostfile;
+                goto parse_string;
+
+        case oGlobalKnownHostsFile2:
+                charptr = &options->system_hostfile2;
+                goto parse_string;
+
+        case oUserKnownHostsFile2:
+                charptr = &options->user_hostfile2;
+                goto parse_string;
+
+        case oHostName:
+                charptr = &options->hostname;
+                goto parse_string;
+
+        case oProxyCommand:
+                charptr = &options->proxy_command;
+                string = xstrdup("");
+                while ((arg = strdelim(&s)) != NULL && *arg != '\0') {
+                        string = xrealloc(string, strlen(string) + strlen(arg) + 2);
+                        strcat(string, " ");
+                        strcat(string, arg);
+                }
+                if (*activep && *charptr == NULL)
+                        *charptr = string;
+                else
+                        xfree(string);
+                return 0;
+
+        case oPort:
+                intptr = &options->port;
+parse_int:
+                arg = strdelim(&s);
+                if (!arg || *arg == '\0')
+                        fatal("%.200s line %d: Missing argument.", filename, linenum);
+                if (arg[0] < '0' || arg[0] > '9')
+                        fatal("%.200s line %d: Bad number.", filename, linenum);
+
+                /* Octal, decimal, or hex format? */
+                value = strtol(arg, &endofnumber, 0);
+                if (arg == endofnumber)
+                        fatal("%.200s line %d: Bad number.", filename, linenum);
+                if (*activep && *intptr == -1)
+                        *intptr = value;
+                break;
+
+        case oConnectionAttempts:
+                intptr = &options->connection_attempts;
+                goto parse_int;
+
+        case oCipher:
+                intptr = &options->cipher;
+                arg = strdelim(&s);
+                if (!arg || *arg == '\0')
+                        fatal("%.200s line %d: Missing argument.", filename, linenum);
+                value = cipher_number(arg);
+                if (value == -1)
+                        fatal("%.200s line %d: Bad cipher '%s'.",
+                              filename, linenum, arg ? arg : "<NONE>");
+                if (*activep && *intptr == -1)
+                        *intptr = value;
+                break;
+
+        case oCiphers:
+                arg = strdelim(&s);
+                if (!arg || *arg == '\0')
+                        fatal("%.200s line %d: Missing argument.", filename, linenum);
+                if (!ciphers_valid(arg))
+                        fatal("%.200s line %d: Bad SSH2 cipher spec '%s'.",
+                              filename, linenum, arg ? arg : "<NONE>");
+                if (*activep && options->ciphers == NULL)
+                        options->ciphers = xstrdup(arg);
+                break;
+
+        case oProtocol:
+                intptr = &options->protocol;
+                arg = strdelim(&s);
+                if (!arg || *arg == '\0')
+                        fatal("%.200s line %d: Missing argument.", filename, linenum);
+                value = proto_spec(arg);
+                if (value == SSH_PROTO_UNKNOWN)
+                        fatal("%.200s line %d: Bad protocol spec '%s'.",
+                              filename, linenum, arg ? arg : "<NONE>");
+                if (*activep && *intptr == SSH_PROTO_UNKNOWN)
+                        *intptr = value;
+                break;
+
+        case oLogLevel:
+                intptr = (int *) &options->log_level;
+                arg = strdelim(&s);
+                value = log_level_number(arg);
+                if (value == (LogLevel) - 1)
+                        fatal("%.200s line %d: unsupported log level '%s'\n",
+                              filename, linenum, arg ? arg : "<NONE>");
+                if (*activep && (LogLevel) * intptr == -1)
+                        *intptr = (LogLevel) value;
+                break;
+
+        case oRemoteForward:
+                arg = strdelim(&s);
+                if (!arg || *arg == '\0')
+                        fatal("%.200s line %d: Missing argument.", filename, linenum);
+                if (arg[0] < '0' || arg[0] > '9')
+                        fatal("%.200s line %d: Badly formatted port number.",
+                              filename, linenum);
+                fwd_port = atoi(arg);
+                arg = strdelim(&s);
+                if (!arg || *arg == '\0')
+                        fatal("%.200s line %d: Missing second argument.",
+                              filename, linenum);
+                if (sscanf(arg, "%255[^:]:%hu", buf, &fwd_host_port) != 2)
+                        fatal("%.200s line %d: Badly formatted host:port.",
+                              filename, linenum);
+                if (*activep)
+                        add_remote_forward(options, fwd_port, buf, fwd_host_port);
+                break;
+
+        case oLocalForward:
+                arg = strdelim(&s);
+                if (!arg || *arg == '\0')
+                        fatal("%.200s line %d: Missing argument.", filename, linenum);
+                if (arg[0] < '0' || arg[0] > '9')
+                        fatal("%.200s line %d: Badly formatted port number.",
+                              filename, linenum);
+                fwd_port = atoi(arg);
+                arg = strdelim(&s);
+                if (!arg || *arg == '\0')
+                        fatal("%.200s line %d: Missing second argument.",
+                              filename, linenum);
+                if (sscanf(arg, "%255[^:]:%hu", buf, &fwd_host_port) != 2)
+                        fatal("%.200s line %d: Badly formatted host:port.",
+                              filename, linenum);
+                if (*activep)
+                        add_local_forward(options, fwd_port, buf, fwd_host_port);
+                break;
+
+        case oHost:
+                *activep = 0;
+                while ((arg = strdelim(&s)) != NULL && *arg != '\0')
+                        if (match_pattern(host, arg)) {
+                                debug("Applying options for %.100s", arg);
+                                *activep = 1;
+                                break;
+                        }
+                /* Avoid garbage check below, as strdelim is done. */
+                return 0;
+
+        case oEscapeChar:
+                intptr = &options->escape_char;
+                arg = strdelim(&s);
+                if (!arg || *arg == '\0')
+                        fatal("%.200s line %d: Missing argument.", filename, linenum);
+                if (arg[0] == '^' && arg[2] == 0 &&
+                    (unsigned char) arg[1] >= 64 && (unsigned char) arg[1] < 128)
+                        value = (unsigned char) arg[1] & 31;
+                else if (strlen(arg) == 1)
+                        value = (unsigned char) arg[0];
+                else if (strcmp(arg, "none") == 0)
+                        value = -2;
+                else {
+                        fatal("%.200s line %d: Bad escape character.",
+                              filename, linenum);
+                        /* NOTREACHED */
+                        value = 0;      /* Avoid compiler warning. */
+                }
+                if (*activep && *intptr == -1)
+                        *intptr = value;
+                break;
+
+        default:
+                fatal("process_config_line: Unimplemented opcode %d", opcode);
+        }
+
+        /* Check that there is no garbage at end of line. */
+        if ((arg = strdelim(&s)) != NULL && *arg != '\0')
+        {
+                fatal("%.200s line %d: garbage at end of line; \"%.200s\".",
+                      filename, linenum, arg);
+        }
+        return 0;
+}
+
+
+/*
+ * Reads the config file and modifies the options accordingly.  Options
+ * should already be initialized before this call.  This never returns if
+ * there is an error.  If the file does not exist, this returns immediately.
+ */
+
+void
+read_config_file(const char *filename, const char *host, Options *options)
+{
+        FILE *f;
+        char line[1024];
+        int active, linenum;
+        int bad_options = 0;
+
+        /* Open the file. */
+        f = fopen(filename, "r");
+        if (!f)
+                return;
+
+        debug("Reading configuration data %.200s", filename);
+
+        /*
+         * Mark that we are now processing the options.  This flag is turned
+         * on/off by Host specifications.
+         */
+        active = 1;
+        linenum = 0;
+        while (fgets(line, sizeof(line), f)) {
+                /* Update line number counter. */
+                linenum++;
+                if (process_config_line(options, host, line, filename, linenum, &active) != 0)
+                        bad_options++;
+        }
+        fclose(f);
+        if (bad_options > 0)
+                fatal("%s: terminating, %d bad configuration options\n",
+                      filename, bad_options);
+}
+
+/*
+ * Initializes options to special values that indicate that they have not yet
+ * been set.  Read_config_file will only set options with this value. Options
+ * are processed in the following order: command line, user config file,
+ * system config file.  Last, fill_default_options is called.
+ */
+
+void
+initialize_options(Options * options)
+{
+        memset(options, 'X', sizeof(*options));
+        options->forward_agent = -1;
+        options->forward_x11 = -1;
+        options->xauth_location = NULL;
+        options->gateway_ports = -1;
+        options->use_privileged_port = -1;
+        options->rhosts_authentication = -1;
+        options->rsa_authentication = -1;
+        options->dsa_authentication = -1;
+        options->skey_authentication = -1;
+#ifdef KRB4
+        options->kerberos_authentication = -1;
+#endif
+#ifdef AFS
+        options->kerberos_tgt_passing = -1;
+        options->afs_token_passing = -1;
+#endif
+        options->password_authentication = -1;
+        options->rhosts_rsa_authentication = -1;
+        options->fallback_to_rsh = -1;
+        options->use_rsh = -1;
+        options->batch_mode = -1;
+        options->check_host_ip = -1;
+        options->strict_host_key_checking = -1;
+        options->compression = -1;
+        options->keepalives = -1;
+        options->compression_level = -1;
+        options->port = -1;
+        options->connection_attempts = -1;
+        options->number_of_password_prompts = -1;
+        options->cipher = -1;
+        options->ciphers = NULL;
+        options->protocol = SSH_PROTO_UNKNOWN;
+        options->num_identity_files = 0;
+        options->num_identity_files2 = 0;
+        options->hostname = NULL;
+        options->proxy_command = NULL;
+        options->user = NULL;
+        options->escape_char = -1;
+        options->system_hostfile = NULL;
+        options->user_hostfile = NULL;
+        options->system_hostfile2 = NULL;
+        options->user_hostfile2 = NULL;
+        options->num_local_forwards = 0;
+        options->num_remote_forwards = 0;
+        options->log_level = (LogLevel) - 1;
+}
+
+/*
+ * Called after processing other sources of option data, this fills those
+ * options for which no value has been specified with their default values.
+ */
+
+void
+fill_default_options(Options * options)
+{
+        if (options->forward_agent == -1)
+                options->forward_agent = 0;
+        if (options->forward_x11 == -1)
+                options->forward_x11 = 0;
+#ifdef XAUTH_PATH
+        if (options->xauth_location == NULL)
+                options->xauth_location = XAUTH_PATH;
+#endif /* XAUTH_PATH */
+        if (options->gateway_ports == -1)
+                options->gateway_ports = 0;
+        if (options->use_privileged_port == -1)
+                options->use_privileged_port = 1;
+        if (options->rhosts_authentication == -1)
+                options->rhosts_authentication = 1;
+        if (options->rsa_authentication == -1)
+                options->rsa_authentication = 1;
+        if (options->dsa_authentication == -1)
+                options->dsa_authentication = 1;
+        if (options->skey_authentication == -1)
+                options->skey_authentication = 0;
+#ifdef KRB4
+        if (options->kerberos_authentication == -1)
+                options->kerberos_authentication = 1;
+#endif /* KRB4 */
+#ifdef AFS
+        if (options->kerberos_tgt_passing == -1)
+                options->kerberos_tgt_passing = 1;
+        if (options->afs_token_passing == -1)
+                options->afs_token_passing = 1;
+#endif /* AFS */
+        if (options->password_authentication == -1)
+                options->password_authentication = 1;
+        if (options->rhosts_rsa_authentication == -1)
+                options->rhosts_rsa_authentication = 1;
+        if (options->fallback_to_rsh == -1)
+                options->fallback_to_rsh = 0;
+        if (options->use_rsh == -1)
+                options->use_rsh = 0;
+        if (options->batch_mode == -1)
+                options->batch_mode = 0;
+        if (options->check_host_ip == -1)
+                options->check_host_ip = 1;
+        if (options->strict_host_key_checking == -1)
+                options->strict_host_key_checking = 2;  /* 2 is default */
+        if (options->compression == -1)
+                options->compression = 0;
+        if (options->keepalives == -1)
+                options->keepalives = 1;
+        if (options->compression_level == -1)
+                options->compression_level = 6;
+        if (options->port == -1)
+                options->port = 0;      /* Filled in ssh_connect. */
+        if (options->connection_attempts == -1)
+                options->connection_attempts = 4;
+        if (options->number_of_password_prompts == -1)
+                options->number_of_password_prompts = 3;
+        /* Selected in ssh_login(). */
+        if (options->cipher == -1)
+                options->cipher = SSH_CIPHER_NOT_SET;
+        /* options->ciphers, default set in myproposals.h */
+        if (options->protocol == SSH_PROTO_UNKNOWN)
+                options->protocol = SSH_PROTO_1|SSH_PROTO_2|SSH_PROTO_1_PREFERRED;
+        if (options->num_identity_files == 0) {
+                options->identity_files[0] =
+                        xmalloc(2 + strlen(SSH_CLIENT_IDENTITY) + 1);
+                sprintf(options->identity_files[0], "~/%.100s", SSH_CLIENT_IDENTITY);
+                options->num_identity_files = 1;
+        }
+        if (options->num_identity_files2 == 0) {
+                options->identity_files2[0] =
+                        xmalloc(2 + strlen(SSH_CLIENT_ID_DSA) + 1);
+                sprintf(options->identity_files2[0], "~/%.100s", SSH_CLIENT_ID_DSA);
+                options->num_identity_files2 = 1;
+        }
+        if (options->escape_char == -1)
+                options->escape_char = '~';
+        if (options->system_hostfile == NULL)
+                options->system_hostfile = SSH_SYSTEM_HOSTFILE;
+        if (options->user_hostfile == NULL)
+                options->user_hostfile = SSH_USER_HOSTFILE;
+        if (options->system_hostfile2 == NULL)
+                options->system_hostfile2 = SSH_SYSTEM_HOSTFILE2;
+        if (options->user_hostfile2 == NULL)
+                options->user_hostfile2 = SSH_USER_HOSTFILE2;
+        if (options->log_level == (LogLevel) - 1)
+                options->log_level = SYSLOG_LEVEL_INFO;
+        /* options->proxy_command should not be set by default */
+        /* options->user will be set in the main program if appropriate */
+        /* options->hostname will be set in the main program if appropriate */
+}