First of all, my native language is spanish so I'd want to apologize if I write bad some (or all) sentences.
I'm developing an App in Xamarin.android that uses Digital Signature on a PDF document and lately the class I use to stamp the signature had a lot of problems. This is the issue I'm facing now:
Fatal signal 6 (SIGABRT), code -6 in tid 30481 (al.FirmaDigital)
I'm pretty new in Xamarin and I don't have idea why is this going on. I've been investigating and I found that this error occurs when a program sends a signal to abort the process. But I don't know what is causing this error.
I only know this error appears when it run the line 175 of the code: objSignedCms.ComputeSignature(objCmsSigner, false); (I used a try/catch but it doesn't throw any exception. The app just close itself and the logcat sends that error).
I let you here the class I'm using to sign the document so you can see if you can help me.
Thanks in advance!
using System;
using System.Collections.Generic;
using System.Linq;
using System.Collections;
using System.IO;
using iTextSharp.text;
using iTextSharp.text.pdf;
using Org.BouncyCastle.X509;
using SysX509 = System.Security.Cryptography.X509Certificates;
using System.Security.Cryptography;
using System.Security.Cryptography.Pkcs;
namespace FirmaDigital.FirmaDigital
{
public static class PDF
{
/// <summary>
/// Firma un documento
/// </summary>
/// <param name="Source">Documento origen</param>
/// <param name="Target">Documento destino</param>
/// <param name="Certificate">Certificado a utilizar</param>
/// <param name="Reason">Razón de la firma</param>
/// <param name="Location">Ubicación</param>
/// <param name="AddVisibleSign">Establece si hay que agregar la firma visible al documento</param>
/// FormatPlace. Posibles valores para Lugar de la firma:
/// A4TL: A4 normal, arriba a la izquierda
/// A4TR: A4 normal, arriba a la derecha
/// A4BL: A4 normal, abajo a la izquierda
/// A4BR: A4 normal, abajo a la derecha
/// A4aTL: A4 apaisado, arriba a la izquierda
/// A4aTR: A4 apaisado, arriba a la derecha
/// A4aBL: A4 apaisado, abajo a la izquierda
/// A4aBR: A4 apaisado, abajo a la derecha
public static void SignHashed(string Source, string Target, SysX509.X509Certificate2 Certificate, string Reason, string Location, bool AddVisibleSign, string FormatPlace, string TSA)
{
X509CertificateParser objCP = new X509CertificateParser();
X509Certificate[] objChain = new X509Certificate[] { objCP.ReadCertificate(Certificate.RawData) };
PdfReader objReader = new PdfReader(Source);
PdfStamper objStamper = PdfStamper.CreateSignature(objReader, new FileStream(Target, FileMode.Create), '\0');
PdfSignatureAppearance objSA = objStamper.SignatureAppearance;
int LastPage = objReader.NumberOfPages;
if (AddVisibleSign)
{
switch (FormatPlace)
{
case "A4TL":
objSA.SetVisibleSignature(new Rectangle(50, 750, 300, 780), LastPage, null);
break;
case "A4TR":
objSA.SetVisibleSignature(new Rectangle(350, 750, 600, 780), LastPage, null);
break;
case "A4BL":
objSA.SetVisibleSignature(new Rectangle(50, 50, 300, 80), LastPage, null);
break;
case "A4BR":
objSA.SetVisibleSignature(new Rectangle(350, 50, 600, 80), LastPage, null);
break;
case "A4aTL":
objSA.SetVisibleSignature(new Rectangle(50, 570, 300, 600), LastPage, null);
break;
case "A4aTR":
objSA.SetVisibleSignature(new Rectangle(530, 570, 780, 600), LastPage, null);
break;
case "A4aBL":
objSA.SetVisibleSignature(new Rectangle(50, 20, 300, 50), LastPage, null);
break;
case "A4aBR":
objSA.SetVisibleSignature(new Rectangle(530, 20, 780, 50), LastPage, null);
break;
}
}
objSA.SignDate = DateTime.Now;
objSA.Certificate = objChain[0];
objSA.Reason = Reason;
objSA.Location = Location;
objSA.Acro6Layers = true;
objSA.SignatureRenderingMode = PdfSignatureAppearance.RenderingMode.DESCRIPTION;
PdfSignature objSignature = new PdfSignature(PdfName.ADOBE_PPKMS, PdfName.ADBE_PKCS7_SHA1);
objSignature.Date = new PdfDate(objSA.SignDate);
objSignature.Name = "Nombre de Prueba";
if (objSA.Reason != null)
objSignature.Reason = objSA.Reason;
if (objSA.Location != null)
objSignature.Location = objSA.Location;
objSA.CryptoDictionary = objSignature;
int intCSize = 4000;
Hashtable objTable = new Hashtable();
objTable[PdfName.CONTENTS] = intCSize * 2 + 2;
var dict = HashtableToDictionary<PdfName, int>(objTable);
objSA.PreClose(dict);
HashAlgorithm objSHA1 = new SHA1CryptoServiceProvider();
Stream objStream = objSA.GetRangeStream();
int intRead = 0;
byte[] bytBuffer = new byte[8192];
while ((intRead = objStream.Read(bytBuffer, 0, 8192)) > 0)
objSHA1.TransformBlock(bytBuffer, 0, intRead, bytBuffer, 0);
objSHA1.TransformFinalBlock(bytBuffer, 0, 0);
byte[] bytPK = SignMsg(objSHA1.Hash, Certificate, false, Source, TSA);
byte[] bytOut = new byte[intCSize];
PdfDictionary objDict = new PdfDictionary();
Array.Copy(bytPK, 0, bytOut, 0, bytPK.Length);
objDict.Put(PdfName.CONTENTS, new PdfString(bytOut).SetHexWriting(true));
objSA.Close(objDict);
}
public static Dictionary<K, V> HashtableToDictionary<K, V>(Hashtable table)
{
return table
.Cast<DictionaryEntry>()
.ToDictionary(kvp => (K)kvp.Key, kvp => (V)kvp.Value);
}
/// <summary>
/// Crea la firma CMS/PKCS #7
/// </summary>
private static byte[] SignMsg(byte[] Message, SysX509.X509Certificate2 SignerCertificate, bool Detached, string Source, string TSA)
{
try
{
//Creamos el contenedor
ContentInfo contentInfo = new ContentInfo(Message);
//Instanciamos el objeto SignedCms con el contenedor
SignedCms objSignedCms = new SignedCms(contentInfo, Detached);
//Creamos el "firmante"
CmsSigner objCmsSigner = new CmsSigner(SignerCertificate);
// Include the following line if the top certificate in the
// smartcard is not in the trusted list.
objCmsSigner.IncludeOption = SysX509.X509IncludeOption.EndCertOnly;
if (TSA != "S/TSA"){
objCmsSigner.UnsignedAttributes.Add(timeData);
}
// Sign the CMS/PKCS #7 message. The second argument is needed to ask for the pin.
objSignedCms.ComputeSignature(objCmsSigner, false);
//Encodeamos el mensaje CMS/PKCS #7
return objSignedCms.Encode();
}
catch (Exception ex)
{
throw ex;
}
}
}
}
[Edit]
I'll let you here the last 10 lines of the logcat:
09-13 13:54:55.788 D/Mono (18211): Assembly Ref addref System.Security.Cryptography.Algorithms[0x9c119fa0] -> mscorlib[0xb46d4580]: 18
Loaded assembly: System.Security.Cryptography.Algorithms.dll [External]
09-13 13:54:55.864 D/Mono (18211): Assembly Ref addref
System.Security.Cryptography.Algorithms[0x9c119fa0] -> System.Core[0xb477c4c0]: 5
09-13 13:54:55.881 D/Mono (18211): Assembly Ref addref System.Memory[0xb46d4b20] -> System.Runtime.CompilerServices.Unsafe[0xb46d4be0]: 2
09-13 13:54:55.882 D/Mono (18211): Unloading image System.Runtime.dll [0x9e0e8300].
09-13 13:54:55.883 D/Mono (18211): Image addref System.Runtime[0x9c119e80] -> System.Runtime.dll[0xb4447000]: 5
09-13 13:54:55.883 D/Mono (18211): Config attempting to parse: 'System.Runtime.dll.config'.
09-13 13:54:55.883 D/Mono (18211): Config attempting to parse: '/usr/local/etc/mono/assemblies/System.Runtime/System.Runtime.config'.
09-13 13:54:55.883 D/Mono (18211): Assembly Ref addref System.Runtime.CompilerServices.Unsafe[0xb46d4be0] -> System.Runtime[0xb46d4dc0]: 3
09-13 13:54:55.887 F/ (18211): * Assertion at /Users/builder/jenkins/workspace/xamarin-android/xamarin-android/external/mono/mono/mini/method-to-ir.c:13643, condition `ins->opcode >= MONO_CEE_LAST' not met
09-13 13:54:55.887 F/libc (18211): Fatal signal 6 (SIGABRT), code -6 in tid 18211 (al.FirmaDigital)
[Edit 2]
This is the logcat after doing what @SushiHangover told me to do:
09-14 11:33:04.450 Hipstreet 7DTB40 Debug 230 AEE not know revents:0
09-14 11:33:04.450 Hipstreet 7DTB40 Debug 230 AEE p 0 poll events 1 revents 0
09-14 11:33:04.450 Hipstreet 7DTB40 Debug 230 AEE p 1 poll events 1 revents 0
09-14 11:33:04.450 Hipstreet 7DTB40 Error 23079 libc Fatal signal 6 (SIGABRT), code -6 in tid 23079 (al.FirmaDigital)
09-14 11:33:04.450 Hipstreet 7DTB40 Debug 230 AEE aed_main_fork_worker: generator 0xb6437148, worker 0xbec4c928, recv_fd 0
09-14 11:33:04.450 Hipstreet 7DTB40 Debug 230 AEE not know revents:0
09-14 11:33:04.450 Hipstreet 7DTB40 Debug 230 AEE $===AEE===AEE===AEE===$
09-14 11:33:04.450 Hipstreet 7DTB40 Debug 230 AEE p 2 poll events 1 revents 1
09-14 11:33:04.449 Hipstreet 7DTB40 Error 23079 * Assertion at /Users/builder/jenkins/workspace/xamarin-android/xamarin-android/external/mono/mono/mini/method-to-ir.c:13643, condition `ins->opcode >= MONO_CEE_LAST' not met
09-14 11:33:04.443 Hipstreet 7DTB40 Debug 23079 Mono Assembly Ref addref System.Runtime.CompilerServices.Unsafe[0xb46d4be0] -> System.Runtime[0xb46d4dc0]: 3
09-14 11:33:04.443 Hipstreet 7DTB40 Debug 23079 Mono Config attempting to parse: '/usr/local/etc/mono/assemblies/System.Runtime/System.Runtime.config'.
09-14 11:33:04.442 Hipstreet 7DTB40 Debug 23079 Mono Config attempting to parse: 'System.Runtime.dll.config'.
