+/* $OpenBSD: auth-options.c,v 1.41 2008/03/26 21:28:14 djm Exp $ */
+/*
+ * Author: Tatu Ylonen <ylo@cs.hut.fi>
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ * All rights reserved
+ * As far as I am concerned, the code I have written for this software
+ * can be used freely for any purpose. Any derived versions of this
+ * software must be clearly marked as such, and if the derived work is
+ * incompatible with the protocol description in the RFC file, it must be
+ * called by a name other than "ssh" or "Secure Shell".
+ */
+
#include "includes.h"
-RCSID("$Id$");
-#include "ssh.h"
-#include "packet.h"
+#include <sys/types.h>
+
+#include <netdb.h>
+#include <pwd.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdarg.h>
+
#include "xmalloc.h"
#include "match.h"
+#include "log.h"
+#include "canohost.h"
+#include "buffer.h"
+#include "channels.h"
+#include "auth-options.h"
+#include "servconf.h"
+#include "misc.h"
+#include "key.h"
+#include "hostfile.h"
+#include "auth.h"
+#ifdef GSSAPI
+#include "ssh-gss.h"
+#endif
+#include "monitor_wrap.h"
/* Flags set authorized_keys flags */
int no_port_forwarding_flag = 0;
int no_agent_forwarding_flag = 0;
int no_x11_forwarding_flag = 0;
int no_pty_flag = 0;
+int no_user_rc = 0;
/* "command=" option. */
char *forced_command = NULL;
/* "environment=" options. */
struct envstring *custom_environment = NULL;
-/* return 1 if access is granted, 0 if not. side effect: sets key option flags */
+/* "tunnel=" option. */
+int forced_tun_device = -1;
+
+extern ServerOptions options;
+
+void
+auth_clear_options(void)
+{
+ no_agent_forwarding_flag = 0;
+ no_port_forwarding_flag = 0;
+ no_pty_flag = 0;
+ no_x11_forwarding_flag = 0;
+ no_user_rc = 0;
+ while (custom_environment) {
+ struct envstring *ce = custom_environment;
+ custom_environment = ce->next;
+ xfree(ce->s);
+ xfree(ce);
+ }
+ if (forced_command) {
+ xfree(forced_command);
+ forced_command = NULL;
+ }
+ forced_tun_device = -1;
+ channel_clear_permitted_opens();
+ auth_debug_reset();
+}
+
+/*
+ * return 1 if access is granted, 0 if not.
+ * side effect: sets key option flags
+ */
int
-auth_parse_options(struct passwd *pw, char *options, unsigned long linenum)
+auth_parse_options(struct passwd *pw, char *opts, char *file, u_long linenum)
{
const char *cp;
- if (!options)
+ int i;
+
+ /* reset options */
+ auth_clear_options();
+
+ if (!opts)
return 1;
- while (*options && *options != ' ' && *options != '\t') {
+
+ while (*opts && *opts != ' ' && *opts != '\t') {
cp = "no-port-forwarding";
- if (strncmp(options, cp, strlen(cp)) == 0) {
- packet_send_debug("Port forwarding disabled.");
+ if (strncasecmp(opts, cp, strlen(cp)) == 0) {
+ auth_debug_add("Port forwarding disabled.");
no_port_forwarding_flag = 1;
- options += strlen(cp);
+ opts += strlen(cp);
goto next_option;
}
cp = "no-agent-forwarding";
- if (strncmp(options, cp, strlen(cp)) == 0) {
- packet_send_debug("Agent forwarding disabled.");
+ if (strncasecmp(opts, cp, strlen(cp)) == 0) {
+ auth_debug_add("Agent forwarding disabled.");
no_agent_forwarding_flag = 1;
- options += strlen(cp);
+ opts += strlen(cp);
goto next_option;
}
cp = "no-X11-forwarding";
- if (strncmp(options, cp, strlen(cp)) == 0) {
- packet_send_debug("X11 forwarding disabled.");
+ if (strncasecmp(opts, cp, strlen(cp)) == 0) {
+ auth_debug_add("X11 forwarding disabled.");
no_x11_forwarding_flag = 1;
- options += strlen(cp);
+ opts += strlen(cp);
goto next_option;
}
cp = "no-pty";
- if (strncmp(options, cp, strlen(cp)) == 0) {
- packet_send_debug("Pty allocation disabled.");
+ if (strncasecmp(opts, cp, strlen(cp)) == 0) {
+ auth_debug_add("Pty allocation disabled.");
no_pty_flag = 1;
- options += strlen(cp);
+ opts += strlen(cp);
+ goto next_option;
+ }
+ cp = "no-user-rc";
+ if (strncasecmp(opts, cp, strlen(cp)) == 0) {
+ auth_debug_add("User rc file execution disabled.");
+ no_user_rc = 1;
+ opts += strlen(cp);
goto next_option;
}
cp = "command=\"";
- if (strncmp(options, cp, strlen(cp)) == 0) {
- int i;
- options += strlen(cp);
- forced_command = xmalloc(strlen(options) + 1);
+ if (strncasecmp(opts, cp, strlen(cp)) == 0) {
+ opts += strlen(cp);
+ forced_command = xmalloc(strlen(opts) + 1);
i = 0;
- while (*options) {
- if (*options == '"')
+ while (*opts) {
+ if (*opts == '"')
break;
- if (*options == '\\' && options[1] == '"') {
- options += 2;
+ if (*opts == '\\' && opts[1] == '"') {
+ opts += 2;
forced_command[i++] = '"';
continue;
}
- forced_command[i++] = *options++;
+ forced_command[i++] = *opts++;
}
- if (!*options) {
+ if (!*opts) {
debug("%.100s, line %lu: missing end quote",
- SSH_USER_PERMITTED_KEYS, linenum);
- packet_send_debug("%.100s, line %lu: missing end quote",
- SSH_USER_PERMITTED_KEYS, linenum);
- continue;
+ file, linenum);
+ auth_debug_add("%.100s, line %lu: missing end quote",
+ file, linenum);
+ xfree(forced_command);
+ forced_command = NULL;
+ goto bad_option;
}
- forced_command[i] = 0;
- packet_send_debug("Forced command: %.900s", forced_command);
- options++;
+ forced_command[i] = '\0';
+ auth_debug_add("Forced command: %.900s", forced_command);
+ opts++;
goto next_option;
}
cp = "environment=\"";
- if (strncmp(options, cp, strlen(cp)) == 0) {
- int i;
+ if (options.permit_user_env &&
+ strncasecmp(opts, cp, strlen(cp)) == 0) {
char *s;
struct envstring *new_envstring;
- options += strlen(cp);
- s = xmalloc(strlen(options) + 1);
+
+ opts += strlen(cp);
+ s = xmalloc(strlen(opts) + 1);
i = 0;
- while (*options) {
- if (*options == '"')
+ while (*opts) {
+ if (*opts == '"')
break;
- if (*options == '\\' && options[1] == '"') {
- options += 2;
+ if (*opts == '\\' && opts[1] == '"') {
+ opts += 2;
s[i++] = '"';
continue;
}
- s[i++] = *options++;
+ s[i++] = *opts++;
}
- if (!*options) {
+ if (!*opts) {
debug("%.100s, line %lu: missing end quote",
- SSH_USER_PERMITTED_KEYS, linenum);
- packet_send_debug("%.100s, line %lu: missing end quote",
- SSH_USER_PERMITTED_KEYS, linenum);
- continue;
+ file, linenum);
+ auth_debug_add("%.100s, line %lu: missing end quote",
+ file, linenum);
+ xfree(s);
+ goto bad_option;
}
- s[i] = 0;
- packet_send_debug("Adding to environment: %.900s", s);
+ s[i] = '\0';
+ auth_debug_add("Adding to environment: %.900s", s);
debug("Adding to environment: %.900s", s);
- options++;
+ opts++;
new_envstring = xmalloc(sizeof(struct envstring));
new_envstring->s = s;
new_envstring->next = custom_environment;
goto next_option;
}
cp = "from=\"";
- if (strncmp(options, cp, strlen(cp)) == 0) {
- int mname, mip;
- char *patterns = xmalloc(strlen(options) + 1);
- int i;
- options += strlen(cp);
+ if (strncasecmp(opts, cp, strlen(cp)) == 0) {
+ const char *remote_ip = get_remote_ipaddr();
+ const char *remote_host = get_canonical_hostname(
+ options.use_dns);
+ char *patterns = xmalloc(strlen(opts) + 1);
+
+ opts += strlen(cp);
i = 0;
- while (*options) {
- if (*options == '"')
+ while (*opts) {
+ if (*opts == '"')
break;
- if (*options == '\\' && options[1] == '"') {
- options += 2;
+ if (*opts == '\\' && opts[1] == '"') {
+ opts += 2;
patterns[i++] = '"';
continue;
}
- patterns[i++] = *options++;
+ patterns[i++] = *opts++;
}
- if (!*options) {
+ if (!*opts) {
debug("%.100s, line %lu: missing end quote",
- SSH_USER_PERMITTED_KEYS, linenum);
- packet_send_debug("%.100s, line %lu: missing end quote",
- SSH_USER_PERMITTED_KEYS, linenum);
- continue;
+ file, linenum);
+ auth_debug_add("%.100s, line %lu: missing end quote",
+ file, linenum);
+ xfree(patterns);
+ goto bad_option;
}
- patterns[i] = 0;
- options++;
- /*
- * Deny access if we get a negative
- * match for the hostname or the ip
- * or if we get not match at all
- */
- mname = match_hostname(get_canonical_hostname(),
- patterns, strlen(patterns));
- mip = match_hostname(get_remote_ipaddr(),
- patterns, strlen(patterns));
- xfree(patterns);
- if (mname == -1 || mip == -1 ||
- (mname != 1 && mip != 1)) {
- log("Authentication tried for %.100s with correct key but not from a permitted host (host=%.200s, ip=%.200s).",
- pw->pw_name, get_canonical_hostname(),
- get_remote_ipaddr());
- packet_send_debug("Your host '%.200s' is not permitted to use this key for login.",
- get_canonical_hostname());
- /* key invalid for this host, reset flags */
- no_agent_forwarding_flag = 0;
- no_port_forwarding_flag = 0;
- no_pty_flag = 0;
- no_x11_forwarding_flag = 0;
- while (custom_environment) {
- struct envstring *ce = custom_environment;
- custom_environment = ce->next;
- xfree(ce->s);
- xfree(ce);
- }
- if (forced_command) {
- xfree(forced_command);
- forced_command = NULL;
- }
+ patterns[i] = '\0';
+ opts++;
+ if (match_host_and_ip(remote_host, remote_ip,
+ patterns) != 1) {
+ xfree(patterns);
+ logit("Authentication tried for %.100s with "
+ "correct key but not from a permitted "
+ "host (host=%.200s, ip=%.200s).",
+ pw->pw_name, remote_host, remote_ip);
+ auth_debug_add("Your host '%.200s' is not "
+ "permitted to use this key for login.",
+ remote_host);
/* deny access */
return 0;
}
+ xfree(patterns);
/* Host name matches. */
goto next_option;
}
+ cp = "permitopen=\"";
+ if (strncasecmp(opts, cp, strlen(cp)) == 0) {
+ char *host, *p;
+ u_short port;
+ char *patterns = xmalloc(strlen(opts) + 1);
+
+ opts += strlen(cp);
+ i = 0;
+ while (*opts) {
+ if (*opts == '"')
+ break;
+ if (*opts == '\\' && opts[1] == '"') {
+ opts += 2;
+ patterns[i++] = '"';
+ continue;
+ }
+ patterns[i++] = *opts++;
+ }
+ if (!*opts) {
+ debug("%.100s, line %lu: missing end quote",
+ file, linenum);
+ auth_debug_add("%.100s, line %lu: missing "
+ "end quote", file, linenum);
+ xfree(patterns);
+ goto bad_option;
+ }
+ patterns[i] = '\0';
+ opts++;
+ p = patterns;
+ host = hpdelim(&p);
+ if (host == NULL || strlen(host) >= NI_MAXHOST) {
+ debug("%.100s, line %lu: Bad permitopen "
+ "specification <%.100s>", file, linenum,
+ patterns);
+ auth_debug_add("%.100s, line %lu: "
+ "Bad permitopen specification", file,
+ linenum);
+ xfree(patterns);
+ goto bad_option;
+ }
+ host = cleanhostname(host);
+ if (p == NULL || (port = a2port(p)) == 0) {
+ debug("%.100s, line %lu: Bad permitopen port "
+ "<%.100s>", file, linenum, p ? p : "");
+ auth_debug_add("%.100s, line %lu: "
+ "Bad permitopen port", file, linenum);
+ xfree(patterns);
+ goto bad_option;
+ }
+ if (options.allow_tcp_forwarding)
+ channel_add_permitted_opens(host, port);
+ xfree(patterns);
+ goto next_option;
+ }
+ cp = "tunnel=\"";
+ if (strncasecmp(opts, cp, strlen(cp)) == 0) {
+ char *tun = NULL;
+ opts += strlen(cp);
+ tun = xmalloc(strlen(opts) + 1);
+ i = 0;
+ while (*opts) {
+ if (*opts == '"')
+ break;
+ tun[i++] = *opts++;
+ }
+ if (!*opts) {
+ debug("%.100s, line %lu: missing end quote",
+ file, linenum);
+ auth_debug_add("%.100s, line %lu: missing end quote",
+ file, linenum);
+ xfree(tun);
+ forced_tun_device = -1;
+ goto bad_option;
+ }
+ tun[i] = '\0';
+ forced_tun_device = a2tun(tun, NULL);
+ xfree(tun);
+ if (forced_tun_device == SSH_TUNID_ERR) {
+ debug("%.100s, line %lu: invalid tun device",
+ file, linenum);
+ auth_debug_add("%.100s, line %lu: invalid tun device",
+ file, linenum);
+ forced_tun_device = -1;
+ goto bad_option;
+ }
+ auth_debug_add("Forced tun device: %d", forced_tun_device);
+ opts++;
+ goto next_option;
+ }
next_option:
/*
* Skip the comma, and move to the next option
* (or break out if there are no more).
*/
- if (!*options)
+ if (!*opts)
fatal("Bugs in auth-options.c option processing.");
- if (*options == ' ' || *options == '\t')
+ if (*opts == ' ' || *opts == '\t')
break; /* End of options. */
- if (*options != ',')
+ if (*opts != ',')
goto bad_option;
- options++;
+ opts++;
/* Process the next option. */
}
+
+ if (!use_privsep)
+ auth_debug_send();
+
/* grant access */
return 1;
bad_option:
- log("Bad options in %.100s file, line %lu: %.50s",
- SSH_USER_PERMITTED_KEYS, linenum, options);
- packet_send_debug("Bad options in %.100s file, line %lu: %.50s",
- SSH_USER_PERMITTED_KEYS, linenum, options);
+ logit("Bad options in %.100s file, line %lu: %.50s",
+ file, linenum, opts);
+ auth_debug_add("Bad options in %.100s file, line %lu: %.50s",
+ file, linenum, opts);
+
+ if (!use_privsep)
+ auth_debug_send();
+
/* deny access */
return 0;
}