Vendor import of OpenSSH.

1 files changed, 708 insertions, 0 deletions

diff --git a/crypto/openssh/readconf.c b/crypto/openssh/readconf.c
new file mode 100644
index 0000000..32afcdd
--- /dev/null
+++ b/crypto/openssh/readconf.c
@@ -0,0 +1,708 @@
+/*
+ * 
+ * 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("$Id: readconf.c,v 1.22 1999/12/01 13:59:15 markus Exp $");
+
+#include "ssh.h"
+#include "cipher.h"
+#include "readconf.h"
+#include "xmalloc.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,
+#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
+} OpCodes;
+
+/* Textual representations of the tokens. */
+
+static struct {
+	const char *name;
+	OpCodes opcode;
+} keywords[] = {
+	{ "forwardagent", oForwardAgent },
+	{ "forwardx11", oForwardX11 },
+	{ "gatewayports", oGatewayPorts },
+	{ "useprivilegedport", oUsePrivilegedPort },
+	{ "rhostsauthentication", oRhostsAuthentication },
+	{ "passwordauthentication", oPasswordAuthentication },
+	{ "rsaauthentication", oRSAAuthentication },
+	{ "skeyauthentication", oSkeyAuthentication },
+#ifdef KRB4
+	{ "kerberosauthentication", oKerberosAuthentication },
+#endif /* KRB4 */
+#ifdef AFS
+	{ "kerberostgtpassing", oKerberosTgtPassing },
+	{ "afstokenpassing", oAFSTokenPassing },
+#endif
+	{ "fallbacktorsh", oFallBackToRsh },
+	{ "usersh", oUseRsh },
+	{ "identityfile", oIdentityFile },
+	{ "hostname", oHostName },
+	{ "proxycommand", oProxyCommand },
+	{ "port", oPort },
+	{ "cipher", oCipher },
+	{ "remoteforward", oRemoteForward },
+	{ "localforward", oLocalForward },
+	{ "user", oUser },
+	{ "host", oHost },
+	{ "escapechar", oEscapeChar },
+	{ "rhostsrsaauthentication", oRhostsRSAAuthentication },
+	{ "globalknownhostsfile", oGlobalKnownHostsFile },
+	{ "userknownhostsfile", oUserKnownHostsFile },
+	{ "connectionattempts", oConnectionAttempts },
+	{ "batchmode", oBatchMode },
+	{ "checkhostip", oCheckHostIP },
+	{ "stricthostkeychecking", oStrictHostKeyChecking },
+	{ "compression", oCompression },
+	{ "compressionlevel", oCompressionLevel },
+	{ "keepalive", oKeepAlives },
+	{ "numberofpasswordprompts", oNumberOfPasswordPrompts },
+	{ "tisauthentication", oTISAuthentication },
+	{ "loglevel", oLogLevel },
+	{ NULL, 0 }
+};
+
+/* Characters considered whitespace in strtok calls. */
+#define WHITESPACE " \t\r\n"
+
+
+/*
+ * 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], *cp, *string, **charptr, *cp2;
+	int opcode, *intptr, value;
+	u_short fwd_port, fwd_host_port;
+
+	/* Skip leading whitespace. */
+	cp = line + strspn(line, WHITESPACE);
+	if (!*cp || *cp == '\n' || *cp == '#')
+		return 0;
+
+	/* Get the keyword. (Each line is supposed to begin with a keyword). */
+	cp = strtok(cp, WHITESPACE);
+	opcode = parse_token(cp, filename, linenum);
+
+	switch (opcode) {
+	case oBadOption:
+		/* don't panic, but count bad options */
+		return -1;
+		/* NOTREACHED */
+	case oForwardAgent:
+		intptr = &options->forward_agent;
+parse_flag:
+		cp = strtok(NULL, WHITESPACE);
+		if (!cp)
+			fatal("%.200s line %d: Missing yes/no argument.", filename, linenum);
+		value = 0;	/* To avoid compiler warning... */
+		if (strcmp(cp, "yes") == 0 || strcmp(cp, "true") == 0)
+			value = 1;
+		else if (strcmp(cp, "no") == 0 || strcmp(cp, "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 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;
+		cp = strtok(NULL, WHITESPACE);
+		if (!cp)
+			fatal("%.200s line %d: Missing yes/no argument.",
+			      filename, linenum);
+		value = 0;	/* To avoid compiler warning... */
+		if (strcmp(cp, "yes") == 0 || strcmp(cp, "true") == 0)
+			value = 1;
+		else if (strcmp(cp, "no") == 0 || strcmp(cp, "false") == 0)
+			value = 0;
+		else if (strcmp(cp, "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:
+		cp = strtok(NULL, WHITESPACE);
+		if (!cp)
+			fatal("%.200s line %d: Missing argument.", filename, linenum);
+		if (*activep) {
+			if (options->num_identity_files >= SSH_MAX_IDENTITY_FILES)
+				fatal("%.200s line %d: Too many identity files specified (max %d).",
+				      filename, linenum, SSH_MAX_IDENTITY_FILES);
+			options->identity_files[options->num_identity_files++] = xstrdup(cp);
+		}
+		break;
+
+	case oUser:
+		charptr = &options->user;
+parse_string:
+		cp = strtok(NULL, WHITESPACE);
+		if (!cp)
+			fatal("%.200s line %d: Missing argument.", filename, linenum);
+		if (*activep && *charptr == NULL)
+			*charptr = xstrdup(cp);
+		break;
+
+	case oGlobalKnownHostsFile:
+		charptr = &options->system_hostfile;
+		goto parse_string;
+
+	case oUserKnownHostsFile:
+		charptr = &options->user_hostfile;
+		goto parse_string;
+
+	case oHostName:
+		charptr = &options->hostname;
+		goto parse_string;
+
+	case oProxyCommand:
+		charptr = &options->proxy_command;
+		string = xstrdup("");
+		while ((cp = strtok(NULL, WHITESPACE)) != NULL) {
+			string = xrealloc(string, strlen(string) + strlen(cp) + 2);
+			strcat(string, " ");
+			strcat(string, cp);
+		}
+		if (*activep && *charptr == NULL)
+			*charptr = string;
+		else
+			xfree(string);
+		return 0;
+
+	case oPort:
+		intptr = &options->port;
+parse_int:
+		cp = strtok(NULL, WHITESPACE);
+		if (!cp)
+			fatal("%.200s line %d: Missing argument.", filename, linenum);
+		if (cp[0] < '0' || cp[0] > '9')
+			fatal("%.200s line %d: Bad number.", filename, linenum);
+
+		/* Octal, decimal, or hex format? */
+		value = strtol(cp, &cp2, 0);
+		if (cp == cp2)
+			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;
+		cp = strtok(NULL, WHITESPACE);
+		value = cipher_number(cp);
+		if (value == -1)
+			fatal("%.200s line %d: Bad cipher '%s'.",
+			      filename, linenum, cp ? cp : "<NONE>");
+		if (*activep && *intptr == -1)
+			*intptr = value;
+		break;
+
+	case oLogLevel:
+		intptr = (int *) &options->log_level;
+		cp = strtok(NULL, WHITESPACE);
+		value = log_level_number(cp);
+		if (value == (LogLevel) - 1)
+			fatal("%.200s line %d: unsupported log level '%s'\n",
+			      filename, linenum, cp ? cp : "<NONE>");
+		if (*activep && (LogLevel) * intptr == -1)
+			*intptr = (LogLevel) value;
+		break;
+
+	case oRemoteForward:
+		cp = strtok(NULL, WHITESPACE);
+		if (!cp)
+			fatal("%.200s line %d: Missing argument.", filename, linenum);
+		if (cp[0] < '0' || cp[0] > '9')
+			fatal("%.200s line %d: Badly formatted port number.",
+			      filename, linenum);
+		fwd_port = atoi(cp);
+		cp = strtok(NULL, WHITESPACE);
+		if (!cp)
+			fatal("%.200s line %d: Missing second argument.",
+			      filename, linenum);
+		if (sscanf(cp, "%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:
+		cp = strtok(NULL, WHITESPACE);
+		if (!cp)
+			fatal("%.200s line %d: Missing argument.", filename, linenum);
+		if (cp[0] < '0' || cp[0] > '9')
+			fatal("%.200s line %d: Badly formatted port number.",
+			      filename, linenum);
+		fwd_port = atoi(cp);
+		cp = strtok(NULL, WHITESPACE);
+		if (!cp)
+			fatal("%.200s line %d: Missing second argument.",
+			      filename, linenum);
+		if (sscanf(cp, "%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 ((cp = strtok(NULL, WHITESPACE)) != NULL)
+			if (match_pattern(host, cp)) {
+				debug("Applying options for %.100s", cp);
+				*activep = 1;
+				break;
+			}
+		/* Avoid garbage check below, as strtok already returned NULL. */
+		return 0;
+
+	case oEscapeChar:
+		intptr = &options->escape_char;
+		cp = strtok(NULL, WHITESPACE);
+		if (!cp)
+			fatal("%.200s line %d: Missing argument.", filename, linenum);
+		if (cp[0] == '^' && cp[2] == 0 &&
+		    (unsigned char) cp[1] >= 64 && (unsigned char) cp[1] < 128)
+			value = (unsigned char) cp[1] & 31;
+		else if (strlen(cp) == 1)
+			value = (unsigned char) cp[0];
+		else if (strcmp(cp, "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 (strtok(NULL, WHITESPACE) != NULL)
+		fatal("%.200s line %d: garbage at end of line.",
+		      filename, linenum);
+	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->gateway_ports = -1;
+	options->use_privileged_port = -1;
+	options->rhosts_authentication = -1;
+	options->rsa_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->num_identity_files = 0;
+	options->hostname = NULL;
+	options->proxy_command = NULL;
+	options->user = NULL;
+	options->escape_char = -1;
+	options->system_hostfile = NULL;
+	options->user_hostfile = 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 = 1;
+	if (options->forward_x11 == -1)
+		options->forward_x11 = 1;
+	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->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 = 1;
+	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;
+	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->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->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 */
+}