ksmimecrypto.cpp

/* This file is part of the KDE project
 *
 * Copyright (C) 2003 Stefan Rompf <sux@loplof.de>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */
 
 
#include <tqptrlist.h>
#include <tqcstring.h>
#include <tqstring.h>
#include <kdebug.h>
 
#include "kopenssl.h"
#include "ksslcertificate.h"
#include "ksslpkcs12.h"
#include "ksmimecrypto.h"
 
// this hack provided by Malte Starostik to avoid glibc/openssl bug
// on some systems
#ifdef KSSL_HAVE_SSL
#define crypt _openssl_crypt
#include <openssl/err.h>
#undef crypt
#endif
 
 
#ifdef KSSL_HAVE_SSL
static const char eot = 0;
 
class KSMIMECryptoPrivate {
    KOpenSSLProxy *kossl;
 
public:
    KSMIMECryptoPrivate(KOpenSSLProxy *kossl);
 
 
    STACK_OF(X509) *certsToX509(TQPtrList<KSSLCertificate> &certs);
 
    KSMIMECrypto::rc signMessage(BIO *clearText,
                 BIO *cipherText,
                 KSSLPKCS12 &privKey, TQPtrList<KSSLCertificate> &certs,
                 bool detached);
 
    KSMIMECrypto::rc encryptMessage(BIO *clearText,
                    BIO *cipherText, KSMIMECrypto::algo algorithm,
                    TQPtrList<KSSLCertificate> &recip);
 
    KSMIMECrypto::rc checkSignature(BIO *clearText,
                    BIO *signature, bool detached,
                    TQPtrList<KSSLCertificate> &recip);
    
    KSMIMECrypto::rc decryptMessage(BIO *cipherText,
                    BIO *clearText,
                    KSSLPKCS12 &privKey);
    
    void MemBIOToQByteArray(BIO *src, TQByteArray &dest);
 
    KSMIMECrypto::rc sslErrToRc(void);
};
 
 
KSMIMECryptoPrivate::KSMIMECryptoPrivate(KOpenSSLProxy *kossl): kossl(kossl) {
}
 
 
STACK_OF(X509) *KSMIMECryptoPrivate::certsToX509(TQPtrList<KSSLCertificate> &certs) {
    STACK_OF(X509) *x509 = reinterpret_cast<STACK_OF(X509)*>(kossl->OPENSSL_sk_new(NULL));
    KSSLCertificate *cert = certs.first();
    while(cert) {
    kossl->OPENSSL_sk_push(x509, cert->getCert());
    cert = certs.next();
    }
    return x509;
}
 
 
KSMIMECrypto::rc KSMIMECryptoPrivate::signMessage(BIO *clearText,
                          BIO *cipherText,
                          KSSLPKCS12 &privKey, TQPtrList<KSSLCertificate> &certs,
                          bool detached) {
 
    STACK_OF(X509) *other = NULL;
    KSMIMECrypto::rc rc;
    int flags = detached?PKCS7_DETACHED:0;
 
    if (certs.count()) other = certsToX509(certs);
 
    PKCS7 *p7 = kossl->PKCS7_sign(privKey.getCertificate()->getCert(), privKey.getPrivateKey(),
                  other, clearText, flags);
 
    if (other) kossl->OPENSSL_sk_free(other);
 
    if (!p7) return sslErrToRc();
 
    if (kossl->i2d_PKCS7_bio(cipherText, p7)) {
    rc = KSMIMECrypto::KSC_R_OK;
    } else {
    rc = sslErrToRc();
    }
 
    kossl->PKCS7_free(p7);
 
    return rc;
}
 
KSMIMECrypto::rc KSMIMECryptoPrivate::encryptMessage(BIO *clearText,
                             BIO *cipherText, KSMIMECrypto::algo algorithm,
                             TQPtrList<KSSLCertificate> &recip) {
    EVP_CIPHER *cipher = NULL;
    KSMIMECrypto::rc rc;
    switch(algorithm) {
    case KSMIMECrypto::KSC_C_DES3_CBC:
        cipher = kossl->EVP_des_ede3_cbc();
        break;
    case KSMIMECrypto::KSC_C_RC2_CBC_128:
        cipher = kossl->EVP_rc2_cbc();
        break;
    case KSMIMECrypto::KSC_C_RC2_CBC_64:
        cipher = kossl->EVP_rc2_64_cbc();
        break;
    case KSMIMECrypto::KSC_C_DES_CBC:
        cipher = kossl->EVP_des_cbc();
        break;
    case KSMIMECrypto::KSC_C_RC2_CBC_40:
        cipher = kossl->EVP_rc2_40_cbc();
        break;
    }
    if (!cipher) return KSMIMECrypto::KSC_R_NOCIPHER;
 
    STACK_OF(X509) *certs = certsToX509(recip);
 
    PKCS7 *p7 = kossl->PKCS7_encrypt(certs, clearText, cipher, 0);
 
    kossl->OPENSSL_sk_free(certs);
 
    if (!p7) return sslErrToRc();
 
    if (kossl->i2d_PKCS7_bio(cipherText, p7)) {
    rc = KSMIMECrypto::KSC_R_OK;
    } else {
    rc = sslErrToRc();
    }
 
    kossl->PKCS7_free(p7);
 
    return rc;
}
 
 
KSMIMECrypto::rc KSMIMECryptoPrivate::checkSignature(BIO *clearText,
                             BIO *signature, bool detached,
                             TQPtrList<KSSLCertificate> &recip) {
    
    PKCS7 *p7 = kossl->d2i_PKCS7_bio(signature, NULL);
    KSMIMECrypto::rc rc = KSMIMECrypto::KSC_R_OTHER;
 
    if (!p7) return sslErrToRc();
 
    BIO *in;
    BIO *out;
    if (detached) {
    in = clearText;
    out = NULL;
    } else {
    in = NULL;
    out = clearText;
    }
 
    X509_STORE *dummystore = kossl->X509_STORE_new();
    if (kossl->PKCS7_verify(p7, NULL, dummystore, in, out, PKCS7_NOVERIFY)) {
    STACK_OF(X509) *signers = kossl->PKCS7_get0_signers(p7, 0, PKCS7_NOVERIFY);
    int num = kossl->OPENSSL_sk_num(signers);
 
    for(int n=0; n<num; n++) {
        KSSLCertificate *signer = KSSLCertificate::fromX509(reinterpret_cast<X509*>(kossl->OPENSSL_sk_value(signers, n)));
        recip.append(signer);
    }
 
    kossl->OPENSSL_sk_free(signers);
    rc = KSMIMECrypto::KSC_R_OK;
    } else {
    rc = sslErrToRc();
    }
 
    kossl->X509_STORE_free(dummystore);
    kossl->PKCS7_free(p7);
 
    return rc;
}
 
 
KSMIMECrypto::rc KSMIMECryptoPrivate::decryptMessage(BIO *cipherText,
                             BIO *clearText,
                             KSSLPKCS12 &privKey) {
    
    PKCS7 *p7 = kossl->d2i_PKCS7_bio(cipherText, NULL);
    KSMIMECrypto::rc rc;
 
    if (!p7) return sslErrToRc();
 
    if (kossl->PKCS7_decrypt(p7, privKey.getPrivateKey(), privKey.getCertificate()->getCert(), 
                 clearText, 0)) {
    rc = KSMIMECrypto::KSC_R_OK;
    } else {
    rc = sslErrToRc();
    }
 
    kossl->PKCS7_free(p7);
 
    return rc;
}
 
 
void KSMIMECryptoPrivate::MemBIOToQByteArray(BIO *src, TQByteArray &dest) {
    char *buf;
    long len = kossl->BIO_get_mem_data(src, &buf);
    dest.assign(buf, len);
    /* Now this goes quite a bit into openssl internals.
       We assume that openssl uses malloc() (it does in
       default config) and rip out the buffer.
    */
    void *ptr = kossl->BIO_get_data(src);
    reinterpret_cast<BUF_MEM *>(ptr)->data = NULL;
}
 
    
KSMIMECrypto::rc KSMIMECryptoPrivate::sslErrToRc(void) {
    unsigned long cerr = kossl->ERR_get_error();
 
    // To be completed and possibly fixed
 
    switch(ERR_GET_REASON(cerr)) {
    case ERR_R_MALLOC_FAILURE:
        return KSMIMECrypto::KSC_R_NOMEM;
    }
 
    switch(ERR_GET_LIB(cerr)) {
    case ERR_LIB_PKCS7:
        switch(ERR_GET_REASON(cerr)) {  
        case PKCS7_R_WRONG_CONTENT_TYPE:
        case PKCS7_R_NO_CONTENT:
        case PKCS7_R_NO_SIGNATURES_ON_DATA:
            return KSMIMECrypto::KSC_R_FORMAT;
            break;
        case PKCS7_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE:
        case PKCS7_R_DECRYPT_ERROR: // Hmm?
            return KSMIMECrypto::KSC_R_WRONGKEY;
            break;
        case PKCS7_R_DIGEST_FAILURE:
            return KSMIMECrypto::KSC_R_VERIFY;
        default:
            break;
        }
        break;
    default:
        break;
    }
 
    kdDebug(7029) <<"KSMIMECrypto: uncaught error " <<ERR_GET_LIB(cerr)
          <<" " <<ERR_GET_REASON(cerr) <<endl;
    return KSMIMECrypto::KSC_R_OTHER;
}    
#endif
 
 
KSMIMECrypto::KSMIMECrypto() {
#ifdef KSSL_HAVE_SSL
    kossl = KOpenSSLProxy::self();
    priv = new KSMIMECryptoPrivate(kossl);
    if (!kossl->hasLibCrypto()) kossl = 0L;
#else
    kossl = 0L;
#endif
}
 
 
KSMIMECrypto::~KSMIMECrypto() {
#ifdef KSSL_HAVE_SSL
    delete priv;
#endif
}
 
 
KSMIMECrypto::rc KSMIMECrypto::signMessage(const TQCString &clearText,
                       TQByteArray &cipherText,
                       const KSSLPKCS12 &privKey,
                       const TQPtrList<KSSLCertificate> &certs,
                       bool detached) {
#ifdef KSSL_HAVE_SSL
    if (!kossl) return KSC_R_NO_SSL;
    BIO *in = kossl->BIO_new_mem_buf((char *)clearText.data(), clearText.size());
    BIO *out = kossl->BIO_new(kossl->BIO_s_mem());
 
    rc rc = priv->signMessage(in, out,
                  const_cast<KSSLPKCS12 &>(privKey),
                  const_cast<TQPtrList<KSSLCertificate> &>(certs),
                  detached);
 
    if (!rc) priv->MemBIOToQByteArray(out, cipherText);
 
    kossl->BIO_free(out);
    kossl->BIO_free(in);
 
    return rc;
#else
    return KSC_R_NO_SSL;
#endif
}
 
 
KSMIMECrypto::rc KSMIMECrypto::checkDetachedSignature(const TQCString &clearText,
                              const TQByteArray &signature,
                              TQPtrList<KSSLCertificate> &foundCerts) {
#ifdef KSSL_HAVE_SSL
    if (!kossl) return KSC_R_NO_SSL;
    BIO *txt = kossl->BIO_new_mem_buf((char *)clearText.data(), clearText.length());
    BIO *sig = kossl->BIO_new_mem_buf((char *)signature.data(), signature.size());
 
    rc rc = priv->checkSignature(txt, sig, true, foundCerts);
 
    kossl->BIO_free(sig);
    kossl->BIO_free(txt);
 
    return rc;
#else
    return KSC_R_NO_SSL;
#endif
}
 
 
KSMIMECrypto::rc KSMIMECrypto::checkOpaqueSignature(const TQByteArray &signedText,
                            TQCString &clearText,
                            TQPtrList<KSSLCertificate> &foundCerts) {
#ifdef KSSL_HAVE_SSL
    if (!kossl) return KSC_R_NO_SSL;
 
    BIO *in = kossl->BIO_new_mem_buf((char *)signedText.data(), signedText.size());
    BIO *out = kossl->BIO_new(kossl->BIO_s_mem());
   
    rc rc = priv->checkSignature(out, in, false, foundCerts);
 
    kossl->BIO_write(out, &eot, 1);
    priv->MemBIOToQByteArray(out, clearText);
 
    kossl->BIO_free(out);
    kossl->BIO_free(in);
 
    return rc;
#else
    return KSC_R_NO_SSL;
#endif
}
 
 
KSMIMECrypto::rc KSMIMECrypto::encryptMessage(const TQCString &clearText,
                          TQByteArray &cipherText,
                          algo algorithm,
                          const TQPtrList<KSSLCertificate> &recip) {
#ifdef KSSL_HAVE_SSL
    if (!kossl) return KSC_R_NO_SSL;
 
    BIO *in = kossl->BIO_new_mem_buf((char *)clearText.data(), clearText.size());
    BIO *out = kossl->BIO_new(kossl->BIO_s_mem());
 
    rc rc = priv->encryptMessage(in,out,algorithm,
                 const_cast< TQPtrList<KSSLCertificate> &>(recip));
 
    if (!rc) priv->MemBIOToQByteArray(out, cipherText);
 
    kossl->BIO_free(out);
    kossl->BIO_free(in);
 
    return rc;
#else
    return KSC_R_NO_SSL;
#endif
}
 
 
KSMIMECrypto::rc KSMIMECrypto::decryptMessage(const TQByteArray &cipherText,
                          TQCString &clearText,
                          const KSSLPKCS12 &privKey) {
#ifdef KSSL_HAVE_SSL
    if (!kossl) return KSC_R_NO_SSL;
 
    BIO *in = kossl->BIO_new_mem_buf((char *)cipherText.data(), cipherText.size());
    BIO *out = kossl->BIO_new(kossl->BIO_s_mem());
 
    rc rc = priv->decryptMessage(in,out,
                 const_cast<KSSLPKCS12 &>(privKey));
 
    kossl->BIO_write(out, &eot, 1);
    priv->MemBIOToQByteArray(out, clearText);
 
    kossl->BIO_free(out);
    kossl->BIO_free(in);
 
    return rc;
#else
    return KSC_R_NO_SSL;
#endif
}