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package sun.security.jca;

import java.security.Provider;

Collection of methods to get and set provider list. Also includes special code for the provider list during JAR verification.
Author: Andreas Sterbenz
Since: 1.5
/** * Collection of methods to get and set provider list. Also includes * special code for the provider list during JAR verification. * * @author Andreas Sterbenz * @since 1.5 */
public class Providers { private static final ThreadLocal<ProviderList> threadLists = new InheritableThreadLocal<>(); // number of threads currently using thread-local provider lists // tracked to allow an optimization if == 0 private static volatile int threadListsUsed; // current system-wide provider list // Note volatile immutable object, so no synchronization needed. private static volatile ProviderList providerList; static { // set providerList to empty list first in case initialization somehow // triggers a getInstance() call (although that should not happen) providerList = ProviderList.EMPTY; providerList = ProviderList.fromSecurityProperties(); } private Providers() { // empty } // After the switch to modules, JDK providers are all in modules and JDK // no longer needs to load signed jars during start up. // // However, for earlier releases, it need special handling to resolve // circularities when loading signed JAR files during startup. The code // below is part of that. // // Basically, before we load data from a signed JAR file, we parse // the PKCS#7 file and verify the signature. We need a // CertificateFactory, Signatures, etc. to do that. We have to make // sure that we do not try to load the implementation from the JAR // file we are just verifying. // // To avoid that, we use different provider settings during JAR // verification. However, we do not want those provider settings to // interfere with other parts of the system. Therefore, we make them local // to the Thread executing the JAR verification code. // // The code here is used by sun.security.util.SignatureFileVerifier. // See there for details. // Hardcoded names of providers to use for JAR verification. // MUST NOT be on the bootclasspath and not in signed JAR files. private static final String[] jarVerificationProviders = { "SUN", "SunRsaSign", // Note: when SunEC is in a signed JAR file, it's not signed // by EC algorithms. So it's still safe to be listed here. "SunEC", }; // Return Sun provider. // This method should only be called by // sun.security.util.ManifestEntryVerifier and java.security.SecureRandom. public static Provider getSunProvider() { return new sun.security.provider.Sun(); }
Start JAR verification. This sets a special provider list for the current thread. You MUST save the return value from this method and you MUST call stopJarVerification() with that object once you are done.
/** * Start JAR verification. This sets a special provider list for * the current thread. You MUST save the return value from this * method and you MUST call stopJarVerification() with that object * once you are done. */
public static Object startJarVerification() { ProviderList currentList = getProviderList(); ProviderList jarList = currentList.getJarList(jarVerificationProviders); if (jarList.getProvider("SUN") == null) { // add backup provider Provider p; try { p = new sun.security.provider.VerificationProvider(); } catch (Exception e) { throw new RuntimeException("Missing provider for jar verification", e); } ProviderList.add(jarList, p); } // return the old thread-local provider list, usually null return beginThreadProviderList(jarList); }
Stop JAR verification. Call once you have completed JAR verification.
/** * Stop JAR verification. Call once you have completed JAR verification. */
public static void stopJarVerification(Object obj) { // restore old thread-local provider list endThreadProviderList((ProviderList)obj); }
Return the current ProviderList. If the thread-local list is set, it is returned. Otherwise, the system wide list is returned.
/** * Return the current ProviderList. If the thread-local list is set, * it is returned. Otherwise, the system wide list is returned. */
public static ProviderList getProviderList() { ProviderList list = getThreadProviderList(); if (list == null) { list = getSystemProviderList(); } return list; }
Set the current ProviderList. Affects the thread-local list if set, otherwise the system wide list.
/** * Set the current ProviderList. Affects the thread-local list if set, * otherwise the system wide list. */
public static void setProviderList(ProviderList newList) { if (getThreadProviderList() == null) { setSystemProviderList(newList); } else { changeThreadProviderList(newList); } }
Get the full provider list with invalid providers (those that could not be loaded) removed. This is the list we need to present to applications.
/** * Get the full provider list with invalid providers (those that * could not be loaded) removed. This is the list we need to * present to applications. */
public static ProviderList getFullProviderList() { ProviderList list; synchronized (Providers.class) { list = getThreadProviderList(); if (list != null) { ProviderList newList = list.removeInvalid(); if (newList != list) { changeThreadProviderList(newList); list = newList; } return list; } } list = getSystemProviderList(); ProviderList newList = list.removeInvalid(); if (newList != list) { setSystemProviderList(newList); list = newList; } return list; } private static ProviderList getSystemProviderList() { return providerList; } private static void setSystemProviderList(ProviderList list) { providerList = list; } public static ProviderList getThreadProviderList() { // avoid accessing the threadlocal if none are currently in use // (first use of ThreadLocal.get() for a Thread allocates a Map) if (threadListsUsed == 0) { return null; } return threadLists.get(); } // Change the thread local provider list. Use only if the current thread // is already using a thread local list and you want to change it in place. // In other cases, use the begin/endThreadProviderList() methods. private static void changeThreadProviderList(ProviderList list) { threadLists.set(list); }
Methods to manipulate the thread local provider list. It is for use by JAR verification (see above) and the SunJSSE FIPS mode only. It should be used as follows: ProviderList list = ...; ProviderList oldList = Providers.beginThreadProviderList(list); try { // code that needs thread local provider list } finally { Providers.endThreadProviderList(oldList); }
/** * Methods to manipulate the thread local provider list. It is for use by * JAR verification (see above) and the SunJSSE FIPS mode only. * * It should be used as follows: * * ProviderList list = ...; * ProviderList oldList = Providers.beginThreadProviderList(list); * try { * // code that needs thread local provider list * } finally { * Providers.endThreadProviderList(oldList); * } * */
public static synchronized ProviderList beginThreadProviderList(ProviderList list) { if (ProviderList.debug != null) { ProviderList.debug.println("ThreadLocal providers: " + list); } ProviderList oldList = threadLists.get(); threadListsUsed++; threadLists.set(list); return oldList; } public static synchronized void endThreadProviderList(ProviderList list) { if (list == null) { if (ProviderList.debug != null) { ProviderList.debug.println("Disabling ThreadLocal providers"); } threadLists.remove(); } else { if (ProviderList.debug != null) { ProviderList.debug.println ("Restoring previous ThreadLocal providers: " + list); } threadLists.set(list); } threadListsUsed--; } }