private List<PdfSignatureOrDocTimestampInfo> getSignatures(
CertificatePool validationCertPool, byte[] originalBytes) {
List<PdfSignatureOrDocTimestampInfo> signatures =
new ArrayList<PdfSignatureOrDocTimestampInfo>();
ByteArrayInputStream bais = null;
PDDocument doc = null;
try {
bais = new ByteArrayInputStream(originalBytes);
doc = PDDocument.load(bais);
List<PDSignature> pdSignatures = doc.getSignatureDictionaries();
if (CollectionUtils.isNotEmpty(pdSignatures)) {
logger.debug("{} signature(s) found", pdSignatures.size());
PdfDict catalog = new PdfBoxDict(doc.getDocumentCatalog().getCOSDictionary(), doc);
PdfDssDict dssDictionary = PdfDssDict.extract(catalog);
for (PDSignature signature : pdSignatures) {
String subFilter = signature.getSubFilter();
byte[] cms = signature.getContents(originalBytes);
if (StringUtils.isEmpty(subFilter) || ArrayUtils.isEmpty(cms)) {
logger.warn("Wrong signature with empty subfilter or cms.");
continue;
}
byte[] signedContent = signature.getSignedContent(originalBytes);
int[] byteRange = signature.getByteRange();
PdfSignatureOrDocTimestampInfo signatureInfo = null;
if (PdfBoxDocTimeStampService.SUB_FILTER_ETSI_RFC3161.getName().equals(subFilter)) {
boolean isArchiveTimestamp = false;
// LT or LTA
if (dssDictionary != null) {
// check is DSS dictionary already exist
if (isDSSDictionaryPresentInPreviousRevision(
getOriginalBytes(byteRange, signedContent))) {
isArchiveTimestamp = true;
}
}
signatureInfo =
new PdfBoxDocTimestampInfo(
validationCertPool,
signature,
dssDictionary,
cms,
signedContent,
isArchiveTimestamp);
} else {
signatureInfo =
new PdfBoxSignatureInfo(
validationCertPool, signature, dssDictionary, cms, signedContent);
}
if (signatureInfo != null) {
signatures.add(signatureInfo);
}
}
Collections.sort(signatures, new PdfSignatureOrDocTimestampInfoComparator());
linkSignatures(signatures);
for (PdfSignatureOrDocTimestampInfo sig : signatures) {
logger.debug(
"Signature "
+ sig.uniqueId()
+ " found with byteRange "
+ Arrays.toString(sig.getSignatureByteRange())
+ " ("
+ sig.getSubFilter()
+ ")");
}
}
} catch (Exception e) {
logger.warn("Cannot analyze signatures : " + e.getMessage(), e);
} finally {
IOUtils.closeQuietly(bais);
IOUtils.closeQuietly(doc);
}
return signatures;
}
