===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/ssh/auth-options.c,v
retrieving revision 1.75
retrieving revision 1.76
diff -u -r1.75 -r1.76
--- src/usr.bin/ssh/auth-options.c	2018/03/03 03:06:02	1.75
+++ src/usr.bin/ssh/auth-options.c	2018/03/03 03:15:51	1.76
@@ -1,15 +1,5 @@
-/* $OpenBSD: auth-options.c,v 1.75 2018/03/03 03:06:02 djm Exp $ */
+/* $OpenBSD: auth-options.c,v 1.76 2018/03/03 03:15:51 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".
- */
-/*
  * Copyright (c) 2018 Damien Miller <djm@mindrot.org>
  *
  * Permission to use, copy, modify, and distribute this software for any
@@ -36,649 +26,15 @@
 #include <ctype.h>
 #include <limits.h>
 
-#include "key.h"	/* XXX for typedef */
-#include "buffer.h"	/* XXX for typedef */
 #include "xmalloc.h"
-#include "match.h"
 #include "ssherr.h"
-#include "ssh2.h"
 #include "log.h"
-#include "canohost.h"
-#include "packet.h"
 #include "sshbuf.h"
 #include "misc.h"
-#include "channels.h"
-#include "servconf.h"
 #include "sshkey.h"
+#include "match.h"
+#include "ssh2.h"
 #include "auth-options.h"
-#include "hostfile.h"
-#include "auth.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;
-int key_is_cert_authority = 0;
-
-/* "command=" option. */
-char *forced_command = NULL;
-
-/* "environment=" options. */
-struct envstring *custom_environment = NULL;
-
-/* "tunnel=" option. */
-int forced_tun_device = -1;
-
-/* "principals=" option. */
-char *authorized_principals = NULL;
-
-extern ServerOptions options;
-
-/* XXX refactor to be stateless */
-
-void
-auth_clear_options(void)
-{
-	struct ssh *ssh = active_state;		/* XXX */
-
-	no_agent_forwarding_flag = 0;
-	no_port_forwarding_flag = 0;
-	no_pty_flag = 0;
-	no_x11_forwarding_flag = 0;
-	no_user_rc = 0;
-	key_is_cert_authority = 0;
-	while (custom_environment) {
-		struct envstring *ce = custom_environment;
-		custom_environment = ce->next;
-		free(ce->s);
-		free(ce);
-	}
-	free(forced_command);
-	forced_command = NULL;
-	free(authorized_principals);
-	authorized_principals = NULL;
-	forced_tun_device = -1;
-	channel_clear_permitted_opens(ssh);
-}
-
-/*
- * Match flag 'opt' in *optsp, and if allow_negate is set then also match
- * 'no-opt'. Returns -1 if option not matched, 1 if option matches or 0
- * if negated option matches. 
- * If the option or negated option matches, then *optsp is updated to
- * point to the first character after the option and, if 'msg' is not NULL
- * then a message based on it added via auth_debug_add().
- */
-static int
-match_flag(const char *opt, int allow_negate, char **optsp, const char *msg)
-{
-	size_t opt_len = strlen(opt);
-	char *opts = *optsp;
-	int negate = 0;
-
-	if (allow_negate && strncasecmp(opts, "no-", 3) == 0) {
-		opts += 3;
-		negate = 1;
-	}
-	if (strncasecmp(opts, opt, opt_len) == 0) {
-		*optsp = opts + opt_len;
-		if (msg != NULL) {
-			auth_debug_add("%s %s.", msg,
-			    negate ? "disabled" : "enabled");
-		}
-		return negate ? 0 : 1;
-	}
-	return -1;
-}
-
-/*
- * return 1 if access is granted, 0 if not.
- * side effect: sets key option flags
- * XXX remove side effects; fill structure instead.
- */
-int
-auth_parse_options(struct passwd *pw, char *opts, const char *file,
-    u_long linenum)
-{
-	struct ssh *ssh = active_state;		/* XXX */
-	const char *cp;
-	int i, r;
-
-	/* reset options */
-	auth_clear_options();
-
-	if (!opts)
-		return 1;
-
-	while (*opts && *opts != ' ' && *opts != '\t') {
-		if ((r = match_flag("cert-authority", 0, &opts, NULL)) != -1) {
-			key_is_cert_authority = r;
-			goto next_option;
-		}
-		if ((r = match_flag("restrict", 0, &opts, NULL)) != -1) {
-			auth_debug_add("Key is restricted.");
-			no_port_forwarding_flag = 1;
-			no_agent_forwarding_flag = 1;
-			no_x11_forwarding_flag = 1;
-			no_pty_flag = 1;
-			no_user_rc = 1;
-			goto next_option;
-		}
-		if ((r = match_flag("port-forwarding", 1, &opts,
-		    "Port forwarding")) != -1) {
-			no_port_forwarding_flag = r != 1;
-			goto next_option;
-		}
-		if ((r = match_flag("agent-forwarding", 1, &opts,
-		    "Agent forwarding")) != -1) {
-			no_agent_forwarding_flag = r != 1;
-			goto next_option;
-		}
-		if ((r = match_flag("x11-forwarding", 1, &opts,
-		    "X11 forwarding")) != -1) {
-			no_x11_forwarding_flag = r != 1;
-			goto next_option;
-		}
-		if ((r = match_flag("pty", 1, &opts,
-		    "PTY allocation")) != -1) {
-			no_pty_flag = r != 1;
-			goto next_option;
-		}
-		if ((r = match_flag("user-rc", 1, &opts,
-		    "User rc execution")) != -1) {
-			no_user_rc = r != 1;
-			goto next_option;
-		}
-		cp = "command=\"";
-		if (strncasecmp(opts, cp, strlen(cp)) == 0) {
-			opts += strlen(cp);
-			free(forced_command);
-			forced_command = xmalloc(strlen(opts) + 1);
-			i = 0;
-			while (*opts) {
-				if (*opts == '"')
-					break;
-				if (*opts == '\\' && opts[1] == '"') {
-					opts += 2;
-					forced_command[i++] = '"';
-					continue;
-				}
-				forced_command[i++] = *opts++;
-			}
-			if (!*opts) {
-				debug("%.100s, line %lu: missing end quote",
-				    file, linenum);
-				auth_debug_add("%.100s, line %lu: missing end quote",
-				    file, linenum);
-				free(forced_command);
-				forced_command = NULL;
-				goto bad_option;
-			}
-			forced_command[i] = '\0';
-			auth_debug_add("Forced command.");
-			opts++;
-			goto next_option;
-		}
-		cp = "principals=\"";
-		if (strncasecmp(opts, cp, strlen(cp)) == 0) {
-			opts += strlen(cp);
-			free(authorized_principals);
-			authorized_principals = xmalloc(strlen(opts) + 1);
-			i = 0;
-			while (*opts) {
-				if (*opts == '"')
-					break;
-				if (*opts == '\\' && opts[1] == '"') {
-					opts += 2;
-					authorized_principals[i++] = '"';
-					continue;
-				}
-				authorized_principals[i++] = *opts++;
-			}
-			if (!*opts) {
-				debug("%.100s, line %lu: missing end quote",
-				    file, linenum);
-				auth_debug_add("%.100s, line %lu: missing end quote",
-				    file, linenum);
-				free(authorized_principals);
-				authorized_principals = NULL;
-				goto bad_option;
-			}
-			authorized_principals[i] = '\0';
-			auth_debug_add("principals: %.900s",
-			    authorized_principals);
-			opts++;
-			goto next_option;
-		}
-		cp = "environment=\"";
-		if (strncasecmp(opts, cp, strlen(cp)) == 0) {
-			char *s;
-			struct envstring *new_envstring;
-
-			opts += strlen(cp);
-			s = xmalloc(strlen(opts) + 1);
-			i = 0;
-			while (*opts) {
-				if (*opts == '"')
-					break;
-				if (*opts == '\\' && opts[1] == '"') {
-					opts += 2;
-					s[i++] = '"';
-					continue;
-				}
-				s[i++] = *opts++;
-			}
-			if (!*opts) {
-				debug("%.100s, line %lu: missing end quote",
-				    file, linenum);
-				auth_debug_add("%.100s, line %lu: missing end quote",
-				    file, linenum);
-				free(s);
-				goto bad_option;
-			}
-			s[i] = '\0';
-			opts++;
-			if (options.permit_user_env) {
-				auth_debug_add("Adding to environment: "
-				    "%.900s", s);
-				debug("Adding to environment: %.900s", s);
-				new_envstring = xcalloc(1,
-				    sizeof(*new_envstring));
-				new_envstring->s = s;
-				new_envstring->next = custom_environment;
-				custom_environment = new_envstring;
-				s = NULL;
-			}
-			free(s);
-			goto next_option;
-		}
-		cp = "from=\"";
-		if (strncasecmp(opts, cp, strlen(cp)) == 0) {
-			const char *remote_ip = ssh_remote_ipaddr(ssh);
-			const char *remote_host = auth_get_canonical_hostname(
-			    ssh, options.use_dns);
-			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);
-				free(patterns);
-				goto bad_option;
-			}
-			patterns[i] = '\0';
-			opts++;
-			switch (match_host_and_ip(remote_host, remote_ip,
-			    patterns)) {
-			case 1:
-				free(patterns);
-				/* Host name matches. */
-				goto next_option;
-			case -1:
-				debug("%.100s, line %lu: invalid criteria",
-				    file, linenum);
-				auth_debug_add("%.100s, line %lu: "
-				    "invalid criteria", file, linenum);
-				/* FALLTHROUGH */
-			case 0:
-				free(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);
-				break;
-			}
-			/* deny access */
-			return 0;
-		}
-		cp = "permitopen=\"";
-		if (strncasecmp(opts, cp, strlen(cp)) == 0) {
-			char *host, *p;
-			int 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);
-				free(patterns);
-				goto bad_option;
-			}
-			patterns[i] = '\0';
-			opts++;
-			p = patterns;
-			/* XXX - add streamlocal support */
-			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);
-				free(patterns);
-				goto bad_option;
-			}
-			host = cleanhostname(host);
-			if (p == NULL || (port = permitopen_port(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);
-				free(patterns);
-				goto bad_option;
-			}
-			if ((options.allow_tcp_forwarding & FORWARD_LOCAL) != 0)
-				channel_add_permitted_opens(ssh, host, port);
-			free(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);
-				free(tun);
-				forced_tun_device = -1;
-				goto bad_option;
-			}
-			tun[i] = '\0';
-			forced_tun_device = a2tun(tun, NULL);
-			free(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 (!*opts)
-			fatal("Bugs in auth-options.c option processing.");
-		if (*opts == ' ' || *opts == '\t')
-			break;		/* End of options. */
-		if (*opts != ',')
-			goto bad_option;
-		opts++;
-		/* Process the next option. */
-	}
-
-	/* grant access */
-	return 1;
-
-bad_option:
-	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);
-
-	/* deny access */
-	return 0;
-}
-
-#define OPTIONS_CRITICAL	1
-#define OPTIONS_EXTENSIONS	2
-static int
-parse_option_list(struct sshbuf *oblob, struct passwd *pw,
-    u_int which, int crit,
-    int *cert_no_port_forwarding_flag,
-    int *cert_no_agent_forwarding_flag,
-    int *cert_no_x11_forwarding_flag,
-    int *cert_no_pty_flag,
-    int *cert_no_user_rc,
-    char **cert_forced_command,
-    int *cert_source_address_done)
-{
-	struct ssh *ssh = active_state;		/* XXX */
-	char *command, *allowed;
-	const char *remote_ip;
-	char *name = NULL;
-	struct sshbuf *c = NULL, *data = NULL;
-	int r, ret = -1, result, found;
-
-	if ((c = sshbuf_fromb(oblob)) == NULL) {
-		error("%s: sshbuf_fromb failed", __func__);
-		goto out;
-	}
-
-	while (sshbuf_len(c) > 0) {
-		sshbuf_free(data);
-		data = NULL;
-		if ((r = sshbuf_get_cstring(c, &name, NULL)) != 0 ||
-		    (r = sshbuf_froms(c, &data)) != 0) {
-			error("Unable to parse certificate options: %s",
-			    ssh_err(r));
-			goto out;
-		}
-		debug3("found certificate option \"%.100s\" len %zu",
-		    name, sshbuf_len(data));
-		found = 0;
-		if ((which & OPTIONS_EXTENSIONS) != 0) {
-			if (strcmp(name, "permit-X11-forwarding") == 0) {
-				*cert_no_x11_forwarding_flag = 0;
-				found = 1;
-			} else if (strcmp(name,
-			    "permit-agent-forwarding") == 0) {
-				*cert_no_agent_forwarding_flag = 0;
-				found = 1;
-			} else if (strcmp(name,
-			    "permit-port-forwarding") == 0) {
-				*cert_no_port_forwarding_flag = 0;
-				found = 1;
-			} else if (strcmp(name, "permit-pty") == 0) {
-				*cert_no_pty_flag = 0;
-				found = 1;
-			} else if (strcmp(name, "permit-user-rc") == 0) {
-				*cert_no_user_rc = 0;
-				found = 1;
-			}
-		}
-		if (!found && (which & OPTIONS_CRITICAL) != 0) {
-			if (strcmp(name, "force-command") == 0) {
-				if ((r = sshbuf_get_cstring(data, &command,
-				    NULL)) != 0) {
-					error("Unable to parse \"%s\" "
-					    "section: %s", name, ssh_err(r));
-					goto out;
-				}
-				if (*cert_forced_command != NULL) {
-					error("Certificate has multiple "
-					    "force-command options");
-					free(command);
-					goto out;
-				}
-				*cert_forced_command = command;
-				found = 1;
-			}
-			if (strcmp(name, "source-address") == 0) {
-				if ((r = sshbuf_get_cstring(data, &allowed,
-				    NULL)) != 0) {
-					error("Unable to parse \"%s\" "
-					    "section: %s", name, ssh_err(r));
-					goto out;
-				}
-				if ((*cert_source_address_done)++) {
-					error("Certificate has multiple "
-					    "source-address options");
-					free(allowed);
-					goto out;
-				}
-				remote_ip = ssh_remote_ipaddr(ssh);
-				result = addr_match_cidr_list(remote_ip,
-				    allowed);
-				free(allowed);
-				switch (result) {
-				case 1:
-					/* accepted */
-					break;
-				case 0:
-					/* no match */
-					logit("Authentication tried for %.100s "
-					    "with valid certificate but not "
-					    "from a permitted host "
-					    "(ip=%.200s).", pw->pw_name,
-					    remote_ip);
-					auth_debug_add("Your address '%.200s' "
-					    "is not permitted to use this "
-					    "certificate for login.",
-					    remote_ip);
-					goto out;
-				case -1:
-				default:
-					error("Certificate source-address "
-					    "contents invalid");
-					goto out;
-				}
-				found = 1;
-			}
-		}
-
-		if (!found) {
-			if (crit) {
-				error("Certificate critical option \"%s\" "
-				    "is not supported", name);
-				goto out;
-			} else {
-				logit("Certificate extension \"%s\" "
-				    "is not supported", name);
-			}
-		} else if (sshbuf_len(data) != 0) {
-			error("Certificate option \"%s\" corrupt "
-			    "(extra data)", name);
-			goto out;
-		}
-		free(name);
-		name = NULL;
-	}
-	/* successfully parsed all options */
-	ret = 0;
-
- out:
-	if (ret != 0 &&
-	    cert_forced_command != NULL &&
-	    *cert_forced_command != NULL) {
-		free(*cert_forced_command);
-		*cert_forced_command = NULL;
-	}
-	free(name);
-	sshbuf_free(data);
-	sshbuf_free(c);
-	return ret;
-}
-
-/*
- * Set options from critical certificate options. These supersede user key
- * options so this must be called after auth_parse_options().
- */
-int
-auth_cert_options(struct sshkey *k, struct passwd *pw, const char **reason)
-{
-	int cert_no_port_forwarding_flag = 1;
-	int cert_no_agent_forwarding_flag = 1;
-	int cert_no_x11_forwarding_flag = 1;
-	int cert_no_pty_flag = 1;
-	int cert_no_user_rc = 1;
-	char *cert_forced_command = NULL;
-	int cert_source_address_done = 0;
-
-	*reason = "invalid certificate options";
-
-	/* Separate options and extensions for v01 certs */
-	if (parse_option_list(k->cert->critical, pw,
-	    OPTIONS_CRITICAL, 1, NULL, NULL, NULL, NULL, NULL,
-	    &cert_forced_command,
-	    &cert_source_address_done) == -1)
-		return -1;
-	if (parse_option_list(k->cert->extensions, pw,
-	    OPTIONS_EXTENSIONS, 0,
-	    &cert_no_port_forwarding_flag,
-	    &cert_no_agent_forwarding_flag,
-	    &cert_no_x11_forwarding_flag,
-	    &cert_no_pty_flag,
-	    &cert_no_user_rc,
-	    NULL, NULL) == -1)
-		return -1;
-
-	no_port_forwarding_flag |= cert_no_port_forwarding_flag;
-	no_agent_forwarding_flag |= cert_no_agent_forwarding_flag;
-	no_x11_forwarding_flag |= cert_no_x11_forwarding_flag;
-	no_pty_flag |= cert_no_pty_flag;
-	no_user_rc |= cert_no_user_rc;
-	/*
-	 * Only permit both CA and key option forced-command if they match.
-	 * Otherwise refuse the certificate.
-	 */
-	if (cert_forced_command != NULL && forced_command != NULL) {
-		if (strcmp(forced_command, cert_forced_command) == 0) {
-			free(forced_command);
-			forced_command = cert_forced_command;
-		} else {
-			*reason = "certificate and key options forced command "
-			    "do not match";
-			free(cert_forced_command);
-			return -1;
-		}
-	} else if (cert_forced_command != NULL)
-		forced_command = cert_forced_command;
-	/* success */
-	*reason = NULL;
-	return 0;
-}
-
-/*
- * authorized_keys options processing.
- */
 
 /*
  * Match flag 'opt' in *optsp, and if allow_negate is set then also match