示例#1
0
/*
 * Checks whether key is allowed in authorized_keys-format file,
 * returns 1 if the key is allowed or 0 otherwise.
 */
static int
check_authkeys_file(FILE *f, char *file, Key* key, struct passwd *pw)
{
	char line[SSH_MAX_PUBKEY_BYTES];
	int found_key = 0;
	u_long linenum = 0;
	Key *found;

	found_key = 0;

	found = NULL;
	while (read_keyfile_line(f, file, line, sizeof(line), &linenum) != -1) {
		char *cp, *key_options = NULL, *fp = NULL;
		const char *reason = NULL;

		/* Always consume entrire file */
		if (found_key)
			continue;
		if (found != NULL)
			key_free(found);
		found = key_new(key_is_cert(key) ? KEY_UNSPEC : key->type);
		auth_clear_options();

		/* Skip leading whitespace, empty and comment lines. */
		for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
			;
		if (!*cp || *cp == '\n' || *cp == '#')
			continue;

		if (key_read(found, &cp) != 1) {
			/* no key?  check if there are options for this key */
			int quoted = 0;
			debug2("user_key_allowed: check options: '%s'", cp);
			key_options = cp;
			for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
				if (*cp == '\\' && cp[1] == '"')
					cp++;	/* Skip both */
				else if (*cp == '"')
					quoted = !quoted;
			}
			/* Skip remaining whitespace. */
			for (; *cp == ' ' || *cp == '\t'; cp++)
				;
			if (key_read(found, &cp) != 1) {
				debug2("user_key_allowed: advance: '%s'", cp);
				/* still no key?  advance to next line*/
				continue;
			}
		}
		if (key_is_cert(key)) {
			if (!key_equal(found, key->cert->signature_key))
				continue;
			if (auth_parse_options(pw, key_options, file,
			    linenum) != 1)
				continue;
			if (!key_is_cert_authority)
				continue;
			if ((fp = sshkey_fingerprint(found,
			    options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
				continue;
			debug("matching CA found: file %s, line %lu, %s %s",
			    file, linenum, key_type(found), fp);
			/*
			 * If the user has specified a list of principals as
			 * a key option, then prefer that list to matching
			 * their username in the certificate principals list.
			 */
			if (authorized_principals != NULL &&
			    !match_principals_option(authorized_principals,
			    key->cert)) {
				reason = "Certificate does not contain an "
				    "authorized principal";
 fail_reason:
				free(fp);
				error("%s", reason);
				auth_debug_add("%s", reason);
				continue;
			}
			if (key_cert_check_authority(key, 0, 0,
			    authorized_principals == NULL ? pw->pw_name : NULL,
			    &reason) != 0)
				goto fail_reason;
			if (auth_cert_options(key, pw, &reason) != 0)
				goto fail_reason;
			verbose("Accepted certificate ID \"%s\" (serial %llu) "
			    "signed by %s CA %s via %s", key->cert->key_id,
			    (unsigned long long)key->cert->serial,
			    key_type(found), fp, file);
			free(fp);
			found_key = 1;
			break;
		} else if (key_equal(found, key)) {
			if (auth_parse_options(pw, key_options, file,
			    linenum) != 1)
				continue;
			if (key_is_cert_authority)
				continue;
			if ((fp = sshkey_fingerprint(found,
			    options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
				continue;
			debug("matching key found: file %s, line %lu %s %s",
			    file, linenum, key_type(found), fp);
			free(fp);
			found_key = 1;
			continue;
		}
	}
	if (found != NULL)
		key_free(found);
	if (!found_key)
		debug2("key not found");
	return found_key;
}
示例#2
0
/* return 1 if user allows given key */
static int
user_key_allowed2(struct passwd *pw, Key *key, char *file)
{
	char line[SSH_MAX_PUBKEY_BYTES];
	const char *reason;
	int found_key = 0;
	FILE *f;
	u_long linenum = 0;
	Key *found;
	char *fp;

	/* Temporarily use the user's uid. */
	temporarily_use_uid(pw);

	debug("trying public key file %s", file);
	f = auth_openkeyfile(file, pw, options.strict_modes);

	if (!f) {
		restore_uid();
		return 0;
	}

	found_key = 0;
	found = key_new(key_is_cert(key) ? KEY_UNSPEC : key->type);

	while (read_keyfile_line(f, file, line, sizeof(line), &linenum) != -1) {
		char *cp, *key_options = NULL;

		auth_clear_options();

		/* Skip leading whitespace, empty and comment lines. */
		for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
			;
		if (!*cp || *cp == '\n' || *cp == '#')
			continue;

		if (key_read(found, &cp) != 1) {
			/* no key?  check if there are options for this key */
			int quoted = 0;
			debug2("user_key_allowed: check options: '%s'", cp);
			key_options = cp;
			for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
				if (*cp == '\\' && cp[1] == '"')
					cp++;	/* Skip both */
				else if (*cp == '"')
					quoted = !quoted;
			}
			/* Skip remaining whitespace. */
			for (; *cp == ' ' || *cp == '\t'; cp++)
				;
			if (key_read(found, &cp) != 1) {
				debug2("user_key_allowed: advance: '%s'", cp);
				/* still no key?  advance to next line*/
				continue;
			}
		}
		if (key_is_cert(key)) {
			if (!key_equal(found, key->cert->signature_key))
				continue;
			if (auth_parse_options(pw, key_options, file,
			    linenum) != 1)
				continue;
			if (!key_is_cert_authority)
				continue;
			fp = key_fingerprint(found, SSH_FP_MD5,
			    SSH_FP_HEX);
			debug("matching CA found: file %s, line %lu, %s %s",
			    file, linenum, key_type(found), fp);
			/*
			 * If the user has specified a list of principals as
			 * a key option, then prefer that list to matching
			 * their username in the certificate principals list.
			 */
			if (authorized_principals != NULL &&
			    !match_principals_option(authorized_principals,
			    key->cert)) {
				reason = "Certificate does not contain an "
				    "authorized principal";
 fail_reason:
				xfree(fp);
				error("%s", reason);
				auth_debug_add("%s", reason);
				continue;
			}
			if (key_cert_check_authority(key, 0, 0,
			    authorized_principals == NULL ? pw->pw_name : NULL,
			    &reason) != 0)
				goto fail_reason;
			if (auth_cert_options(key, pw) != 0) {
				xfree(fp);
				continue;
			}
			verbose("Accepted certificate ID \"%s\" "
			    "signed by %s CA %s via %s", key->cert->key_id,
			    key_type(found), fp, file);
			xfree(fp);
			found_key = 1;
			break;
		} else if (key_equal(found, key)) {
			if (auth_parse_options(pw, key_options, file,
			    linenum) != 1)
				continue;
			if (key_is_cert_authority)
				continue;
			found_key = 1;
			debug("matching key found: file %s, line %lu",
			    file, linenum);
			fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
			verbose("Found matching %s key: %s",
			    key_type(found), fp);
			xfree(fp);
			break;
		}
	}
	restore_uid();
	fclose(f);
	key_free(found);
	if (!found_key)
		debug2("key not found");
	return found_key;
}
示例#3
0
/* return 1 if user allows given key */
static int
user_key_allowed2(struct passwd *pw, Key *key, char *file)
{
	char line[SSH_MAX_PUBKEY_BYTES];
	const char *reason;
	int found_key = 0;
	FILE *f;
	u_long linenum = 0;
	Key *found;
	char *fp;
#ifdef WITH_LDAP_PUBKEY
	ldap_key_t * k;
	unsigned int i = 0;
#endif

	/* Temporarily use the user's uid. */
	temporarily_use_uid(pw);

#ifdef WITH_LDAP_PUBKEY
	found_key = 0;
	/* allocate a new key type */
	found = key_new(key->type);
 
	/* first check if the options is enabled, then try.. */
	if (options.lpk.on) {
	    debug("[LDAP] trying LDAP first uid=%s",pw->pw_name);
	    if (ldap_ismember(&options.lpk, pw->pw_name) > 0) {
		if ((k = ldap_getuserkey(&options.lpk, pw->pw_name)) != NULL) {
		    /* Skip leading whitespace, empty and comment lines. */
		    for (i = 0 ; i < k->num ; i++) {
			/* dont forget if multiple keys to reset options */
			char *cp, *xoptions = NULL;

			for (cp = (char *)k->keys[i]->bv_val; *cp == ' ' || *cp == '\t'; cp++)
			    ;
			if (!*cp || *cp == '\n' || *cp == '#')
			    continue;

			if (key_read(found, &cp) != 1) {
			    /* no key?  check if there are options for this key */
			    int quoted = 0;
			    debug2("[LDAP] user_key_allowed: check options: '%s'", cp);
			    xoptions = cp;
			    for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
				if (*cp == '\\' && cp[1] == '"')
				    cp++;	/* Skip both */
				else if (*cp == '"')
				    quoted = !quoted;
			    }
			    /* Skip remaining whitespace. */
			    for (; *cp == ' ' || *cp == '\t'; cp++)
				;
			    if (key_read(found, &cp) != 1) {
				debug2("[LDAP] user_key_allowed: advance: '%s'", cp);
				/* still no key?  advance to next line*/
				continue;
			    }
			}

			if (key_equal(found, key) &&
				auth_parse_options(pw, xoptions, file, linenum) == 1) {
			    found_key = 1;
			    debug("[LDAP] matching key found");
			    fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
			    verbose("[LDAP] Found matching %s key: %s", key_type(found), fp);

			    /* restoring memory */
			    ldap_keys_free(k);
			    xfree(fp);
			    restore_uid();
			    key_free(found);
			    return found_key;
			    break;
			}
		    }/* end of LDAP for() */
		} else {
		    logit("[LDAP] no keys found for '%s'!", pw->pw_name);
		}
	    } else {
		logit("[LDAP] '%s' is not in '%s'", pw->pw_name, options.lpk.sgroup);
	    }
	}
#endif
	debug("trying public key file %s", file);
	f = auth_openkeyfile(file, pw, options.strict_modes);

	if (!f) {
		restore_uid();
		return 0;
	}

	found_key = 0;
	found = key_new(key_is_cert(key) ? KEY_UNSPEC : key->type);

	while (read_keyfile_line(f, file, line, sizeof(line), &linenum) != -1) {
		char *cp, *key_options = NULL;

		auth_clear_options();

		/* Skip leading whitespace, empty and comment lines. */
		for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
			;
		if (!*cp || *cp == '\n' || *cp == '#')
			continue;

		if (key_read(found, &cp) != 1) {
			/* no key?  check if there are options for this key */
			int quoted = 0;
			debug2("user_key_allowed: check options: '%s'", cp);
			key_options = cp;
			for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
				if (*cp == '\\' && cp[1] == '"')
					cp++;	/* Skip both */
				else if (*cp == '"')
					quoted = !quoted;
			}
			/* Skip remaining whitespace. */
			for (; *cp == ' ' || *cp == '\t'; cp++)
				;
			if (key_read(found, &cp) != 1) {
				debug2("user_key_allowed: advance: '%s'", cp);
				/* still no key?  advance to next line*/
				continue;
			}
		}
		if (key_is_cert(key)) {
			if (!key_equal(found, key->cert->signature_key))
				continue;
			if (auth_parse_options(pw, key_options, file,
			    linenum) != 1)
				continue;
			if (!key_is_cert_authority)
				continue;
			fp = key_fingerprint(found, SSH_FP_MD5,
			    SSH_FP_HEX);
			debug("matching CA found: file %s, line %lu, %s %s",
			    file, linenum, key_type(found), fp);
			/*
			 * If the user has specified a list of principals as
			 * a key option, then prefer that list to matching
			 * their username in the certificate principals list.
			 */
			if (authorized_principals != NULL &&
			    !match_principals_option(authorized_principals,
			    key->cert)) {
				reason = "Certificate does not contain an "
				    "authorized principal";
 fail_reason:
				xfree(fp);
				error("%s", reason);
				auth_debug_add("%s", reason);
				continue;
			}
			if (key_cert_check_authority(key, 0, 0,
			    authorized_principals == NULL ? pw->pw_name : NULL,
			    &reason) != 0)
				goto fail_reason;
			if (auth_cert_options(key, pw) != 0) {
				xfree(fp);
				continue;
			}
			verbose("Accepted certificate ID \"%s\" "
			    "signed by %s CA %s via %s", key->cert->key_id,
			    key_type(found), fp, file);
			xfree(fp);
			found_key = 1;
			break;
		} else if (key_equal(found, key)) {
			if (auth_parse_options(pw, key_options, file,
			    linenum) != 1)
				continue;
			if (key_is_cert_authority)
				continue;
			found_key = 1;
			debug("matching key found: file %s, line %lu",
			    file, linenum);
			fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
			verbose("Found matching %s key: %s",
			    key_type(found), fp);
			xfree(fp);
			break;
		}
	}
	restore_uid();
	fclose(f);
	key_free(found);
	if (!found_key)
		debug2("key not found");
	return found_key;
}