diff options
Diffstat (limited to 'libraries/spongycastle/mail/src/main/java/org/spongycastle/mail/smime/SMIMEGenerator.java')
| -rw-r--r-- | libraries/spongycastle/mail/src/main/java/org/spongycastle/mail/smime/SMIMEGenerator.java | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/libraries/spongycastle/mail/src/main/java/org/spongycastle/mail/smime/SMIMEGenerator.java b/libraries/spongycastle/mail/src/main/java/org/spongycastle/mail/smime/SMIMEGenerator.java new file mode 100644 index 000000000..168cc4a42 --- /dev/null +++ b/libraries/spongycastle/mail/src/main/java/org/spongycastle/mail/smime/SMIMEGenerator.java @@ -0,0 +1,223 @@ +package org.bouncycastle.mail.smime; + +import java.io.IOException; +import java.security.NoSuchAlgorithmException; +import java.security.Provider; +import java.util.Enumeration; +import java.util.HashMap; +import java.util.Map; + +import javax.crypto.KeyGenerator; +import javax.mail.Header; +import javax.mail.MessagingException; +import javax.mail.Multipart; +import javax.mail.Session; +import javax.mail.internet.MimeBodyPart; +import javax.mail.internet.MimeMessage; + +import org.bouncycastle.cms.CMSEnvelopedGenerator; +import org.bouncycastle.util.Strings; + +/** + * super class of the various generators. + */ +public class SMIMEGenerator +{ + private static Map BASE_CIPHER_NAMES = new HashMap(); + + static + { + BASE_CIPHER_NAMES.put(CMSEnvelopedGenerator.DES_EDE3_CBC, "DESEDE"); + BASE_CIPHER_NAMES.put(CMSEnvelopedGenerator.AES128_CBC, "AES"); + BASE_CIPHER_NAMES.put(CMSEnvelopedGenerator.AES192_CBC, "AES"); + BASE_CIPHER_NAMES.put(CMSEnvelopedGenerator.AES256_CBC, "AES"); + } + + protected boolean useBase64 = true; + protected String encoding = "base64"; // default sets base64 + + /** + * base constructor + */ + protected SMIMEGenerator() + { + } + + /** + * set the content-transfer-encoding for the CMS block (enveloped data, signature, etc...) in the message. + * + * @param encoding the encoding to use, default "base64", use "binary" for a binary encoding. + */ + public void setContentTransferEncoding( + String encoding) + { + this.encoding = encoding; + this.useBase64 = Strings.toLowerCase(encoding).equals("base64"); + } + + /** + * Make sure we have a valid content body part - setting the headers + * with defaults if neccessary. + */ + protected MimeBodyPart makeContentBodyPart( + MimeBodyPart content) + throws SMIMEException + { + // + // add the headers to the body part - if they are missing, in + // the event they have already been set the content settings override + // any defaults that might be set. + // + try + { + MimeMessage msg = new MimeMessage((Session)null); + + Enumeration e = content.getAllHeaders(); + + msg.setDataHandler(content.getDataHandler()); + + while (e.hasMoreElements()) + { + Header hdr =(Header)e.nextElement(); + + msg.setHeader(hdr.getName(), hdr.getValue()); + } + + msg.saveChanges(); + + // + // we do this to make sure at least the default headers are + // set in the body part. + // + e = msg.getAllHeaders(); + + while (e.hasMoreElements()) + { + Header hdr =(Header)e.nextElement(); + + if (Strings.toLowerCase(hdr.getName()).startsWith("content-")) + { + content.setHeader(hdr.getName(), hdr.getValue()); + } + } + } + catch (MessagingException e) + { + throw new SMIMEException("exception saving message state.", e); + } + + return content; + } + + /** + * extract an appropriate body part from the passed in MimeMessage + */ + protected MimeBodyPart makeContentBodyPart( + MimeMessage message) + throws SMIMEException + { + MimeBodyPart content = new MimeBodyPart(); + + // + // add the headers to the body part. + // + try + { + message.removeHeader("Message-Id"); + message.removeHeader("Mime-Version"); + + // JavaMail has a habit of reparsing some content types, if the bodypart is + // a multipart it might be signed, we rebuild the body part using the raw input stream for the message. + try + { + if (message.getContent() instanceof Multipart) + { + content.setContent(message.getRawInputStream(), message.getContentType()); + + extractHeaders(content, message); + + return content; + } + } + catch (MessagingException e) + { + // fall back to usual method below + } + + content.setContent(message.getContent(), message.getContentType()); + + content.setDataHandler(message.getDataHandler()); + + extractHeaders(content, message); + } + catch (MessagingException e) + { + throw new SMIMEException("exception saving message state.", e); + } + catch (IOException e) + { + throw new SMIMEException("exception getting message content.", e); + } + + return content; + } + + private void extractHeaders(MimeBodyPart content, MimeMessage message) + throws MessagingException + { + Enumeration e = message.getAllHeaders(); + + while (e.hasMoreElements()) + { + Header hdr =(Header)e.nextElement(); + + content.addHeader(hdr.getName(), hdr.getValue()); + } + } + + protected KeyGenerator createSymmetricKeyGenerator( + String encryptionOID, + Provider provider) + throws NoSuchAlgorithmException + { + try + { + return createKeyGenerator(encryptionOID, provider); + } + catch (NoSuchAlgorithmException e) + { + try + { + String algName = (String)BASE_CIPHER_NAMES.get(encryptionOID); + if (algName != null) + { + return createKeyGenerator(algName, provider); + } + } + catch (NoSuchAlgorithmException ex) + { + // ignore + } + if (provider != null) + { + return createSymmetricKeyGenerator(encryptionOID, null); + } + throw e; + } + } + + private KeyGenerator createKeyGenerator( + String algName, + Provider provider) + throws NoSuchAlgorithmException + { + if (provider != null) + { + return KeyGenerator.getInstance(algName, provider); + } + else + { + return KeyGenerator.getInstance(algName); + } + } +} |