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Diffstat (limited to 'libjava/classpath/gnu/javax/security/auth/login/ConfigFileParser.java')
| -rw-r--r-- | libjava/classpath/gnu/javax/security/auth/login/ConfigFileParser.java | 346 |
1 files changed, 346 insertions, 0 deletions
diff --git a/libjava/classpath/gnu/javax/security/auth/login/ConfigFileParser.java b/libjava/classpath/gnu/javax/security/auth/login/ConfigFileParser.java new file mode 100644 index 000000000..5c4c4261f --- /dev/null +++ b/libjava/classpath/gnu/javax/security/auth/login/ConfigFileParser.java @@ -0,0 +1,346 @@ +/* ConfigFileParser.java -- JAAS Login Configuration default syntax parser + Copyright (C) 2006 Free Software Foundation, Inc. + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + + +package gnu.javax.security.auth.login; + +import gnu.java.security.Configuration; + +import java.io.IOException; +import java.io.Reader; +import java.util.ArrayList; +import java.util.HashMap; +import java.util.List; +import java.util.Map; +import java.util.logging.Logger; + +import javax.security.auth.login.AppConfigurationEntry; + +/** + * A parser that knows how to interpret JAAS Login Module Configuration files + * written in the <i>default syntax</i> which is interpreted as adhering to + * the following grammar: + * + * <pre> + * CONFIG ::= APP_OR_OTHER_ENTRY+ + * APP_OR_OTHER_ENTRY ::= APP_NAME_OR_OTHER JAAS_CONFIG_BLOCK + * APP_NAME_OR_OTHER ::= APP_NAME + * | 'other' + * JAAS_CONFIG_BLOCK ::= '{' (LOGIN_MODULE_ENTRY ';')+ '}' ';' + * LOGIN_MODULE_ENTRY ::= MODULE_CLASS FLAG MODULE_OPTION* ';' + * FLAG ::= 'required' + * | 'requisite' + * | 'sufficient' + * | 'optional' + * MODULE_OPTION ::= PARAM_NAME '=' PARAM_VALUE + * + * APP_NAME ::= JAVA_IDENTIFIER + * MODULE_CLASS ::= JAVA_IDENTIFIER ('.' JAVA_IDENTIFIER)* + * PARAM_NAME ::= STRING + * PARAM_VALUE ::= '"' STRING '"' | ''' STRING ''' | STRING + * </pre> + * + * <p>This parser handles UTF-8 entities when used as APP_NAME and PARAM_VALUE. + * It also checks for the use of Java identifiers used in MODULE_CLASS, thus + * minimizing the risks of having {@link java.lang.ClassCastException}s thrown + * at runtime due to syntactically invalid names.</p> + * + * <p>In the above context, a JAVA_IDENTIFIER is a sequence of tokens, + * separated by the character '.'. Each of these tokens obeys the following:</p> + * + * <ol> + * <li>its first character yields <code>true</code> when used as an input to + * the {@link java.lang.Character#isJavaIdentifierStart(char)}, and</li> + * <li>all remaining characters, yield <code>true</code> when used as an + * input to {@link java.lang.Character#isJavaIdentifierPart(char)}.</li> + * </ol> + */ +public final class ConfigFileParser +{ + private static final Logger log = Logger.getLogger(ConfigFileParser.class.getName()); + private ConfigFileTokenizer cft; + private Map map = new HashMap(); + + // default 0-arguments constructor + + /** + * Returns the parse result as a {@link Map} where the keys are application + * names, and the entries are {@link List}s of {@link AppConfigurationEntry} + * entries, one for each login module entry, in the order they were + * encountered, for that application name in the just parsed configuration + * file. + */ + public Map getLoginModulesMap() + { + return map; + } + + /** + * Parses the {@link Reader}'s contents assuming it is in the <i>default + * syntax</i>. + * + * @param r the {@link Reader} whose contents are assumed to be a JAAS Login + * Configuration Module file written in the <i>default syntax</i>. + * @throws IOException if an exception occurs while parsing the input. + */ + public void parse(Reader r) throws IOException + { + initParser(r); + + while (parseAppOrOtherEntry()) + { + /* do nothing */ + } + } + + private void initParser(Reader r) throws IOException + { + map.clear(); + + cft = new ConfigFileTokenizer(r); + } + + /** + * @return <code>true</code> if an APP_OR_OTHER_ENTRY was correctly parsed. + * Returns <code>false</code> otherwise. + * @throws IOException if an exception occurs while parsing the input. + */ + private boolean parseAppOrOtherEntry() throws IOException + { + int c = cft.nextToken(); + if (c == ConfigFileTokenizer.TT_EOF) + return false; + + if (c != ConfigFileTokenizer.TT_WORD) + { + cft.pushBack(); + return false; + } + + String appName = cft.sval; + if (Configuration.DEBUG) + log.fine("APP_NAME_OR_OTHER = " + appName); + if (cft.nextToken() != '{') + abort("Missing '{' after APP_NAME_OR_OTHER"); + + List lmis = new ArrayList(); + while (parseACE(lmis)) + { + /* do nothing */ + } + + c = cft.nextToken(); + if (c != '}') + abort("Was expecting '}' but found " + (char) c); + + c = cft.nextToken(); + if (c != ';') + abort("Was expecting ';' but found " + (char) c); + + List listOfACEs = (List) map.get(appName); + if (listOfACEs == null) + { + listOfACEs = new ArrayList(); + map.put(appName, listOfACEs); + } + listOfACEs.addAll(lmis); + return !appName.equalsIgnoreCase("other"); + } + + /** + * @return <code>true</code> if a LOGIN_MODULE_ENTRY was correctly parsed. + * Returns <code>false</code> otherwise. + * @throws IOException if an exception occurs while parsing the input. + */ + private boolean parseACE(List listOfACEs) throws IOException + { + int c = cft.nextToken(); + if (c != ConfigFileTokenizer.TT_WORD) + { + cft.pushBack(); + return false; + } + + String clazz = validateClassName(cft.sval); + if (Configuration.DEBUG) + log.fine("MODULE_CLASS = " + clazz); + + if (cft.nextToken() != ConfigFileTokenizer.TT_WORD) + abort("Was expecting FLAG but found none"); + + String flag = cft.sval; + if (Configuration.DEBUG) + log.fine("DEBUG: FLAG = " + flag); + AppConfigurationEntry.LoginModuleControlFlag f = null; + if (flag.equalsIgnoreCase("required")) + f = AppConfigurationEntry.LoginModuleControlFlag.REQUIRED; + else if (flag.equalsIgnoreCase("requisite")) + f = AppConfigurationEntry.LoginModuleControlFlag.REQUISITE; + else if (flag.equalsIgnoreCase("sufficient")) + f = AppConfigurationEntry.LoginModuleControlFlag.SUFFICIENT; + else if (flag.equalsIgnoreCase("optional")) + f = AppConfigurationEntry.LoginModuleControlFlag.OPTIONAL; + else + abort("Unknown Flag: " + flag); + + Map options = new HashMap(); + String paramName, paramValue; + c = cft.nextToken(); + while (c != ';') + { + if (c != ConfigFileTokenizer.TT_WORD) + abort("Was expecting PARAM_NAME but got '" + ((char) c) + "'"); + + paramName = cft.sval; + if (Configuration.DEBUG) + log.fine("PARAM_NAME = " + paramName); + if (cft.nextToken() != '=') + abort("Missing '=' after PARAM_NAME"); + + c = cft.nextToken(); + if (c != '"' && c != '\'') + { + if (Configuration.DEBUG) + log.fine("Was expecting a quoted string but got no quote character." + + " Assume unquoted string"); + } + paramValue = expandParamValue(cft.sval); + if (Configuration.DEBUG) + log.fine("PARAM_VALUE = " + paramValue); + options.put(paramName, paramValue); + + c = cft.nextToken(); + } + AppConfigurationEntry ace = new AppConfigurationEntry(clazz, f, options); + if (Configuration.DEBUG) + log.fine("LOGIN_MODULE_ENTRY = " + ace); + listOfACEs.add(ace); + return true; + } + + private void abort(String m) throws IOException + { + if (Configuration.DEBUG) + { + log.fine(m); + log.fine("Map (so far) = " + String.valueOf(map)); + } + throw new IOException(m); + } + + private String validateClassName(String cn) throws IOException + { + if (cn.startsWith(".") || cn.endsWith(".")) + abort("MODULE_CLASS MUST NOT start or end with a '.'"); + + String[] tokens = cn.split("\\."); + for (int i = 0; i < tokens.length; i++) + { + String t = tokens[i]; + if (! Character.isJavaIdentifierStart(t.charAt(0))) + abort("Class name [" + cn + + "] contains an invalid sub-package identifier: " + t); + + // we dont check the rest of the characters for isJavaIdentifierPart() + // because that's what the tokenizer does. + } + + return cn; + } + + /** + * The documentation of the {@link javax.security.auth.login.Configuration} + * states that: <i>"...If a String in the form, ${system.property}, occurs in + * the value, it will be expanded to the value of the system property."</i>. + * This method ensures this is the case. If such a string can not be expanded + * then it is left AS IS, assuming the LoginModule knows what to do with it. + * + * <p><b>IMPORTANT</b>: This implementation DOES NOT handle embedded ${} + * constructs. + * + * @param s the raw parameter value, incl. eventually strings of the form + * <code>${system.property}</code>. + * @return the input string with every occurence of + * <code>${system.property}</code> replaced with the value of the + * corresponding System property at the time of this method invocation. If + * the string is not a known System property name, then the complete sequence + * (incl. the ${} characters are passed AS IS. + */ + private String expandParamValue(String s) + { + String result = s; + try + { + int searchNdx = 0; + while (searchNdx < result.length()) + { + int i = s.indexOf("${", searchNdx); + if (i == -1) + break; + + int j = s.indexOf("}", i + 2); + if (j == -1) + { + if (Configuration.DEBUG) + log.fine("Found a ${ prefix with no } suffix. Ignore"); + break; + } + + String sysPropName = s.substring(i + 2, j); + if (Configuration.DEBUG) + log.fine("Found a reference to System property " + sysPropName); + String sysPropValue = System.getProperty(sysPropName); + if (Configuration.DEBUG) + log.fine("Resolved " + sysPropName + " to '" + sysPropValue + "'"); + if (sysPropValue != null) + { + result = s.substring(0, i) + sysPropValue + s.substring(j + 1); + searchNdx = i + sysPropValue.length(); + } + else + searchNdx = j + 1; + } + } + catch (Exception x) + { + if (Configuration.DEBUG) + log.fine("Exception (ignored) while expanding " + s + ": " + x); + } + + return result; + } +} |