openssl: Add support for CMS-style signatures in PKCS#7 (RSA-PSS, ECDSA)

diff --git a/src/libstrongswan/plugins/openssl/openssl_pkcs7.c b/src/libstrongswan/plugins/openssl/openssl_pkcs7.c
index aadd91772fa51f005e2f84b4f690e29858a60f12..3adb02dea8cc83aa136004f920b55e1451fb0bbe 100644 (file)
--- a/src/libstrongswan/plugins/openssl/openssl_pkcs7.c
+++ b/src/libstrongswan/plugins/openssl/openssl_pkcs7.c
@@ -213,7 +213,8 @@ typedef struct {
 /**
  * Verify signerInfo signature
  */
-static auth_cfg_t *verify_signature(CMS_SignerInfo *si, int hash_oid)
+static auth_cfg_t *verify_signature(CMS_SignerInfo *si,
+                                                                       signature_params_t *sig_alg)
 {
        enumerator_t *enumerator;
        public_key_t *key;
@@ -249,7 +250,8 @@ static auth_cfg_t *verify_signature(CMS_SignerInfo *si, int hash_oid)
        /* TODO: find a better way to access and verify the signature */
        sig = openssl_asn1_str2chunk(si->signature);
        enumerator = lib->credmgr->create_trusted_enumerator(lib->credmgr,
-                                                                                                               KEY_RSA, serial, FALSE);
+                                                               key_type_from_signature_scheme(sig_alg->scheme),
+                                                               serial, FALSE);
        while (enumerator->enumerate(enumerator, &cert, &auth))
        {
                if (issuer->equals(issuer, cert->get_issuer(cert)))
@@ -257,7 +259,7 @@ static auth_cfg_t *verify_signature(CMS_SignerInfo *si, int hash_oid)
                        key = cert->get_public_key(cert);
                        if (key)
                        {
-                               if (key->verify(key, signature_scheme_from_oid(hash_oid), NULL,
+                               if (key->verify(key, sig_alg->scheme, sig_alg->params,
                                                                attrs, sig))
                                {
                                        found = auth->clone(auth);
@@ -340,6 +342,8 @@ METHOD(enumerator_t, signature_enumerate, bool,
        {
                CMS_SignerInfo *si;
                X509_ALGOR *digest, *sig;
+               signature_params_t sig_alg = {};
+               chunk_t sig_scheme;
                int hash_oid;
 
                /* clean up previous round */
@@ -350,12 +354,24 @@ METHOD(enumerator_t, signature_enumerate, bool,
 
                CMS_SignerInfo_get0_algs(si, NULL, NULL, &digest, &sig);
                hash_oid = openssl_asn1_known_oid(digest->algorithm);
-               if (openssl_asn1_known_oid(sig->algorithm) != OID_RSA_ENCRYPTION)
+               if (openssl_asn1_known_oid(sig->algorithm) == OID_RSA_ENCRYPTION)
                {
-                       DBG1(DBG_LIB, "only RSA digest encryption supported");
-                       continue;
+                       /* derive the signature scheme from the digest algorithm
+                        * for the classic PKCS#7 RSA mechansim */
+                       sig_alg.scheme = signature_scheme_from_oid(hash_oid);
+               }
+               else
+               {
+                       sig_scheme = openssl_i2chunk(X509_ALGOR, sig);
+                       if (!signature_params_parse(sig_scheme, 0, &sig_alg))
+                       {
+                               free(sig_scheme.ptr);
+                               continue;
+                       }
+                       free(sig_scheme.ptr);
                }
-               this->auth = verify_signature(si, hash_oid);
+               this->auth = verify_signature(si, &sig_alg);
+               signature_params_clear(&sig_alg);
                if (!this->auth)
                {
                        DBG1(DBG_LIB, "unable to verify pkcs7 attributes signature");