Add certificate validation and PGP/MIME encryption; rename to pro.thinhha.mailsender

- validation: CertificateValidator checks revocation, expiry, matching
  user ID, a valid communications encryption subkey and the algorithm
  policy; uses the earlier expiry when PGPainless and Bouncy Castle disagree
- crypto: PgpEncryptor (ASCII armor, hidden recipients for Bcc)
- mime: PgpMimeEncryptor builds RFC 3156 multipart/encrypted from the
  whole CRLF-canonical inner entity, keeping envelope headers in the clear
- autoconfigure: validator and encryptor beans
- demo: encrypts when a valid key is found, plaintext otherwise
- rename groupId and Java packages to pro.thinhha.mailsender

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01G71TQ5jDETVwdUJxGAwaiT

mailsender-pgp-spring-boot-autoconfigure/src/main/java/pro/thinhha/mailsender/pgp/autoconfigure/PgpMailAutoConfiguration.java

@@ -1,4 +1,4 @@
-package io.github.sneakybugmaster.mailsender.pgp.autoconfigure;
+package pro.thinhha.mailsender.pgp.autoconfigure;
 
 import java.io.IOException;
 import java.io.InputStream;
@@ -18,19 +18,23 @@ import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Primary;
 import org.springframework.core.io.Resource;
 
-import io.github.sneakybugmaster.mailsender.pgp.discovery.CachingKeyDiscovery;
-import io.github.sneakybugmaster.mailsender.pgp.discovery.Certificates;
-import io.github.sneakybugmaster.mailsender.pgp.discovery.CompositeKeyDiscovery;
-import io.github.sneakybugmaster.mailsender.pgp.discovery.HostResolver;
-import io.github.sneakybugmaster.mailsender.pgp.discovery.HttpWkdFetcher;
-import io.github.sneakybugmaster.mailsender.pgp.discovery.KeyDiscovery;
-import io.github.sneakybugmaster.mailsender.pgp.discovery.StaticKeyDiscovery;
-import io.github.sneakybugmaster.mailsender.pgp.discovery.WkdFetcher;
-import io.github.sneakybugmaster.mailsender.pgp.discovery.WkdKeyDiscovery;
+import pro.thinhha.mailsender.pgp.crypto.PgpEncryptor;
+import pro.thinhha.mailsender.pgp.discovery.CachingKeyDiscovery;
+import pro.thinhha.mailsender.pgp.discovery.Certificates;
+import pro.thinhha.mailsender.pgp.discovery.CompositeKeyDiscovery;
+import pro.thinhha.mailsender.pgp.discovery.HostResolver;
+import pro.thinhha.mailsender.pgp.discovery.HttpWkdFetcher;
+import pro.thinhha.mailsender.pgp.discovery.KeyDiscovery;
+import pro.thinhha.mailsender.pgp.discovery.StaticKeyDiscovery;
+import pro.thinhha.mailsender.pgp.discovery.WkdFetcher;
+import pro.thinhha.mailsender.pgp.discovery.WkdKeyDiscovery;
+import pro.thinhha.mailsender.pgp.mime.PgpMimeEncryptor;
+import pro.thinhha.mailsender.pgp.validation.CertificateValidator;
 
 /**
- * Key discovery beans: pinned keys first, then WKD behind a cache. The primary {@link KeyDiscovery} bean is the
- * combined chain; {@link CachingKeyDiscovery} is exposed separately so applications can evict entries.
+ * Key discovery (pinned keys first, then WKD behind a cache), certificate validation and PGP/MIME encryption beans.
+ * The primary {@link KeyDiscovery} bean is the combined chain; {@link CachingKeyDiscovery} is exposed separately so
+ * applications can evict entries.
  */
 @AutoConfiguration
 @EnableConfigurationProperties(PgpMailProperties.class)
@@ -75,6 +79,24 @@ public class PgpMailAutoConfiguration {
         return new CompositeKeyDiscovery(chain);
     }
 
+    @Bean
+    @ConditionalOnMissingBean
+    CertificateValidator pgpCertificateValidator() {
+        return new CertificateValidator();
+    }
+
+    @Bean
+    @ConditionalOnMissingBean
+    PgpEncryptor pgpEncryptor() {
+        return new PgpEncryptor();
+    }
+
+    @Bean
+    @ConditionalOnMissingBean
+    PgpMimeEncryptor pgpMimeEncryptor(PgpEncryptor encryptor) {
+        return new PgpMimeEncryptor(encryptor);
+    }
+
     private static List<OpenPGPCertificate> read(String email, Resource resource) {
         try (InputStream in = resource.getInputStream()) {
             List<OpenPGPCertificate> certificates = Certificates.parse(in.readAllBytes());

mailsender-pgp-spring-boot-autoconfigure/src/main/java/pro/thinhha/mailsender/pgp/autoconfigure/PgpMailProperties.java

@@ -1,4 +1,4 @@
-package io.github.sneakybugmaster.mailsender.pgp.autoconfigure;
+package pro.thinhha.mailsender.pgp.autoconfigure;
 
 import java.time.Duration;
 import java.util.Map;
@@ -8,7 +8,7 @@ import org.springframework.boot.context.properties.bind.DefaultValue;
 import org.springframework.core.io.Resource;
 import org.springframework.util.unit.DataSize;
 
-import io.github.sneakybugmaster.mailsender.pgp.discovery.WkdFallback;
+import pro.thinhha.mailsender.pgp.discovery.WkdFallback;
 
 /**
  * {@code mail.pgp.*} configuration.

mailsender-pgp-spring-boot-autoconfigure/src/main/resources/META-INF/spring/org.springframework.boot.autoconfigure.AutoConfiguration.imports

@@ -1 +1 @@
-io.github.sneakybugmaster.mailsender.pgp.autoconfigure.PgpMailAutoConfiguration
+pro.thinhha.mailsender.pgp.autoconfigure.PgpMailAutoConfiguration

mailsender-pgp-spring-boot-autoconfigure/src/test/java/pro/thinhha/mailsender/pgp/autoconfigure/PgpMailAutoConfigurationTest.java

@@ -1,4 +1,4 @@
-package io.github.sneakybugmaster.mailsender.pgp.autoconfigure;
+package pro.thinhha.mailsender.pgp.autoconfigure;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -13,12 +13,14 @@ import org.pgpainless.PGPainless;
 import org.springframework.boot.autoconfigure.AutoConfigurations;
 import org.springframework.boot.test.context.runner.ApplicationContextRunner;
 
-import io.github.sneakybugmaster.mailsender.pgp.discovery.CachingKeyDiscovery;
-import io.github.sneakybugmaster.mailsender.pgp.discovery.DiscoveryResult;
-import io.github.sneakybugmaster.mailsender.pgp.discovery.DiscoverySource;
-import io.github.sneakybugmaster.mailsender.pgp.discovery.KeyDiscovery;
-import io.github.sneakybugmaster.mailsender.pgp.discovery.WkdFallback;
-import io.github.sneakybugmaster.mailsender.pgp.discovery.WkdFetcher;
+import pro.thinhha.mailsender.pgp.discovery.CachingKeyDiscovery;
+import pro.thinhha.mailsender.pgp.discovery.DiscoveryResult;
+import pro.thinhha.mailsender.pgp.discovery.DiscoverySource;
+import pro.thinhha.mailsender.pgp.discovery.KeyDiscovery;
+import pro.thinhha.mailsender.pgp.discovery.WkdFallback;
+import pro.thinhha.mailsender.pgp.discovery.WkdFetcher;
+import pro.thinhha.mailsender.pgp.mime.PgpMimeEncryptor;
+import pro.thinhha.mailsender.pgp.validation.CertificateValidator;
 
 class PgpMailAutoConfigurationTest {
 
@@ -31,7 +33,8 @@ class PgpMailAutoConfigurationTest {
     @Test
     void createsDiscoveryChainWithDefaults() {
         runner.run(context -> {
-            assertThat(context).hasSingleBean(WkdFetcher.class).hasSingleBean(CachingKeyDiscovery.class);
+            assertThat(context).hasSingleBean(WkdFetcher.class).hasSingleBean(CachingKeyDiscovery.class)
+                    .hasSingleBean(CertificateValidator.class).hasSingleBean(PgpMimeEncryptor.class);
             assertThat(context.getBean(KeyDiscovery.class)).isNotInstanceOf(CachingKeyDiscovery.class);
 
             PgpMailProperties properties = context.getBean(PgpMailProperties.class);