X-Git-Url: https://main.carlh.net/gitweb/?a=blobdiff_plain;f=src%2Fcertificate_chain.cc;h=6b4216b5eeadb2a73f2428aaf26a7d2f6d1066e7;hb=d3598922d970bba6fcb468c331e1f0a33bef1a0f;hp=ac01d860d3c5c567aaa643ed29b714f6e2266f69;hpb=14ce6b8765f47db4f2cc4ab4d2eff64486792e62;p=libdcp.git diff --git a/src/certificate_chain.cc b/src/certificate_chain.cc index ac01d860..6b4216b5 100644 --- a/src/certificate_chain.cc +++ b/src/certificate_chain.cc @@ -51,6 +51,7 @@ #include #include #include +#include #include #include #include @@ -200,6 +201,7 @@ CertificateChain::CertificateChain ( f << "[ req ]\n" << "distinguished_name = req_distinguished_name\n" << "x509_extensions = v3_ca\n" + << "string_mask = nombstr\n" << "[ v3_ca ]\n" << "basicConstraints = critical,CA:true,pathlen:3\n" << "keyUsage = keyCertSign,cRLSign\n" @@ -233,6 +235,7 @@ CertificateChain::CertificateChain ( f << "[ default ]\n" << "distinguished_name = req_distinguished_name\n" << "x509_extensions = v3_ca\n" + << "string_mask = nombstr\n" << "[ v3_ca ]\n" << "basicConstraints = critical,CA:true,pathlen:2\n" << "keyUsage = keyCertSign,cRLSign\n" @@ -271,6 +274,7 @@ CertificateChain::CertificateChain ( f << "[ default ]\n" << "distinguished_name = req_distinguished_name\n" << "x509_extensions = v3_ca\n" + << "string_mask = nombstr\n" << "[ v3_ca ]\n" << "basicConstraints = critical,CA:false\n" << "keyUsage = digitalSignature,keyEncipherment\n" @@ -326,9 +330,8 @@ CertificateChain::CertificateChain (string s) } } - if (!attempt_reorder ()) { - throw MiscError ("could not find certificate chain order"); - } + /* This will throw an exception if the chain cannot be ordered */ + leaf_to_root (); } /** @return Root certificate */ @@ -336,34 +339,33 @@ Certificate CertificateChain::root () const { DCP_ASSERT (!_certificates.empty()); - return _certificates.front (); + return root_to_leaf().front (); } /** @return Leaf certificate */ Certificate CertificateChain::leaf () const { - DCP_ASSERT (_certificates.size() >= 2); - return _certificates.back (); + DCP_ASSERT (!_certificates.empty()); + return root_to_leaf().back (); } -/** @return Certificates in order from root to leaf */ +/** @return Certificates in order from leaf to root */ CertificateChain::List -CertificateChain::root_to_leaf () const +CertificateChain::leaf_to_root () const { - return _certificates; + List l = root_to_leaf (); + l.reverse (); + return l; } -/** @return Certificates in order from leaf to root */ CertificateChain::List -CertificateChain::leaf_to_root () const +CertificateChain::unordered () const { - List c = _certificates; - c.reverse (); - return c; + return _certificates; } -/** Add a certificate to the end of the chain. +/** Add a certificate to the chain. * @param c Certificate to add. */ void @@ -398,64 +400,99 @@ CertificateChain::remove (int i) } } -/** Check to see if the chain is valid (i.e. root signs the intermediate, intermediate +bool +CertificateChain::chain_valid () const +{ + return chain_valid (_certificates); +} + +/** Check to see if a chain is valid (i.e. root signs the intermediate, intermediate * signs the leaf and so on) and that the private key (if there is one) matches the * leaf certificate. * @return true if it's ok, false if not. */ bool -CertificateChain::valid () const +CertificateChain::chain_valid (List const & chain) const { - /* Check the certificate chain */ + /* Here I am taking a chain of certificates A/B/C/D and checking validity of B wrt A, + C wrt B and D wrt C. It also appears necessary to check the issuer of B/C/D matches + the subject of A/B/C; I don't understand why. I'm sure there's a better way of doing + this with OpenSSL but the documentation does not appear not likely to reveal it + any time soon. + */ X509_STORE* store = X509_STORE_new (); if (!store) { - return false; + throw MiscError ("could not create X509 store"); } - for (List::const_iterator i = _certificates.begin(); i != _certificates.end(); ++i) { + /* Put all the certificates into the store */ + for (List::const_iterator i = chain.begin(); i != chain.end(); ++i) { + if (!X509_STORE_add_cert (store, i->x509 ())) { + X509_STORE_free (store); + return false; + } + } + + /* Verify each one */ + for (List::const_iterator i = chain.begin(); i != chain.end(); ++i) { List::const_iterator j = i; ++j; - if (j == _certificates.end ()) { + if (j == chain.end ()) { break; } - if (!X509_STORE_add_cert (store, i->x509 ())) { - X509_STORE_free (store); - return false; - } - X509_STORE_CTX* ctx = X509_STORE_CTX_new (); if (!ctx) { X509_STORE_free (store); - return false; + throw MiscError ("could not create X509 store context"); } X509_STORE_set_flags (store, 0); - if (!X509_STORE_CTX_init (ctx, store, j->x509 (), 0)) { + if (!X509_STORE_CTX_init (ctx, store, j->x509(), 0)) { X509_STORE_CTX_free (ctx); X509_STORE_free (store); - return false; + throw MiscError ("could not initialise X509 store context"); } - int v = X509_verify_cert (ctx); + int const v = X509_verify_cert (ctx); X509_STORE_CTX_free (ctx); - if (v == 0) { + if (v != 1) { X509_STORE_free (store); return false; } + + /* I don't know why OpenSSL doesn't check this in verify_cert, but without this check + the certificates_validation8 test fails. + */ + if (j->issuer() != i->subject()) { + X509_STORE_free (store); + return false; + } + } X509_STORE_free (store); - /* Check that the leaf certificate matches the private key, if there is one */ + return true; +} - if (!_key) { +/** Check that there is a valid private key for the leaf certificate. + * Will return true if there are no certificates. + */ +bool +CertificateChain::private_key_valid () const +{ + if (_certificates.empty ()) { return true; } + if (!_key) { + return false; + } + BIO* bio = BIO_new_mem_buf (const_cast (_key->c_str ()), -1); if (!bio) { throw MiscError ("could not create memory BIO"); @@ -463,28 +500,56 @@ CertificateChain::valid () const RSA* private_key = PEM_read_bio_RSAPrivateKey (bio, 0, 0, 0); RSA* public_key = leaf().public_key (); + +#if OPENSSL_VERSION_NUMBER > 0x10100000L + BIGNUM const * private_key_n; + RSA_get0_key(private_key, &private_key_n, 0, 0); + BIGNUM const * public_key_n; + RSA_get0_key(public_key, &public_key_n, 0, 0); + bool const valid = !BN_cmp (private_key_n, public_key_n); +#else bool const valid = !BN_cmp (private_key->n, public_key->n); +#endif BIO_free (bio); return valid; } -/** @return true if the chain is now in order from root to leaf, - * false if no correct order was found. - */ bool -CertificateChain::attempt_reorder () +CertificateChain::valid (string* reason) const { - List original = _certificates; - _certificates.sort (); + try { + root_to_leaf (); + } catch (CertificateChainError& e) { + if (reason) { + *reason = "certificates do not form a chain"; + } + return false; + } + + if (!private_key_valid ()) { + if (reason) { + *reason = "private key does not exist, or does not match leaf certificate"; + } + return false; + } + + return true; +} + +/** @return Certificates in order from root to leaf */ +CertificateChain::List +CertificateChain::root_to_leaf () const +{ + List rtl = _certificates; + rtl.sort (); do { - if (valid ()) { - return true; + if (chain_valid (rtl)) { + return rtl; } - } while (std::next_permutation (_certificates.begin(), _certificates.end ())); + } while (std::next_permutation (rtl.begin(), rtl.end())); - _certificates = original; - return false; + throw CertificateChainError ("certificate chain is not consistent"); } /** Add a <Signer> and <ds:Signature> nodes to an XML node. @@ -497,6 +562,7 @@ CertificateChain::sign (xmlpp::Element* parent, Standard standard) const /* */ xmlpp::Element* signer = parent->add_child("Signer"); + signer->set_namespace_declaration ("http://www.w3.org/2000/09/xmldsig#", "dsig"); xmlpp::Element* data = signer->add_child("X509Data", "dsig"); xmlpp::Element* serial_element = data->add_child("X509IssuerSerial", "dsig"); serial_element->add_child("X509IssuerName", "dsig")->add_child_text (leaf().issuer()); @@ -505,7 +571,9 @@ CertificateChain::sign (xmlpp::Element* parent, Standard standard) const /* */ - xmlpp::Element* signature = parent->add_child("Signature", "dsig"); + xmlpp::Element* signature = parent->add_child("Signature"); + signature->set_namespace_declaration ("http://www.w3.org/2000/09/xmldsig#", "dsig"); + signature->set_namespace ("dsig"); xmlpp::Element* signed_info = signature->add_child ("SignedInfo", "dsig"); signed_info->add_child("CanonicalizationMethod", "dsig")->set_attribute ("Algorithm", "http://www.w3.org/TR/2001/REC-xml-c14n-20010315"); @@ -571,11 +639,6 @@ CertificateChain::add_signature_value (xmlpp::Node* parent, string ns) const throw runtime_error ("could not read private key"); } - /* XXX: set key name to the PEM string: this can't be right! */ - if (xmlSecKeySetName (signature_context->signKey, reinterpret_cast (_key->c_str())) < 0) { - throw MiscError ("could not set key name"); - } - int const r = xmlSecDSigCtxSign (signature_context, parent->cobj ()); if (r < 0) { throw MiscError (String::compose ("could not sign (%1)", r));