Adapt ASN1_item_sign_ctx() for use with provided keypairs

The mechanism to do this is to ask the signature operation for the DER
encoded AlgorithmIdentifier that corresponds to the combination of
signature algorithm and digest algorithm.

Reviewed-by: Shane Lontis <shane.lontis@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/10920)

diff --git a/crypto/asn1/a_sign.c b/crypto/asn1/a_sign.c
index 564a500cf427e46a61258122d62e51cfd37e0c7f..0089ce29dd5c928810457e8cba8ce69270ced173 100644 (file)
--- a/crypto/asn1/a_sign.c
+++ b/crypto/asn1/a_sign.c
@@ -18,6 +18,7 @@
 #include <openssl/x509.h>
 #include <openssl/objects.h>
 #include <openssl/buffer.h>
+#include <openssl/core_names.h>
 #include "crypto/asn1.h"
 #include "crypto/evp.h"
 
@@ -156,11 +157,51 @@ int ASN1_item_sign_ctx(const ASN1_ITEM *it,
     }
 
     if (pkey->ameth == NULL) {
-        ASN1err(ASN1_F_ASN1_ITEM_SIGN_CTX, ASN1_R_DIGEST_AND_KEY_TYPE_NOT_SUPPORTED);
-        goto err;
-    }
+        EVP_PKEY_CTX *pctx = EVP_MD_CTX_pkey_ctx(ctx);
+        OSSL_PARAM params[2];
+        unsigned char aid[128];
+        size_t aid_len = 0;
+
+        if (pctx == NULL
+            || !EVP_PKEY_CTX_IS_SIGNATURE_OP(pctx)) {
+            ASN1err(ASN1_F_ASN1_ITEM_SIGN_CTX, ASN1_R_CONTEXT_NOT_INITIALISED);
+            goto err;
+        }
+
+        params[0] =
+            OSSL_PARAM_construct_octet_string(OSSL_SIGNATURE_PARAM_ALGORITHM_ID,
+                                              aid, sizeof(aid));
+        params[1] = OSSL_PARAM_construct_end();
+
+        if (EVP_PKEY_CTX_get_params(pctx, params) <= 0)
+            goto err;
+
+        if ((aid_len = params[0].return_size) == 0) {
+            ASN1err(ASN1_F_ASN1_ITEM_SIGN_CTX,
+                    ASN1_R_DIGEST_AND_KEY_TYPE_NOT_SUPPORTED);
+            goto err;
+        }
+
+        if (algor1 != NULL) {
+            const unsigned char *pp = aid;
+
+            if (d2i_X509_ALGOR(&algor1, &pp, aid_len) == NULL) {
+                ASN1err(ASN1_F_ASN1_ITEM_SIGN_CTX, ERR_R_INTERNAL_ERROR);
+                goto err;
+            }
+        }
+
+        if (algor2 != NULL) {
+            const unsigned char *pp = aid;
+
+            if (d2i_X509_ALGOR(&algor2, &pp, aid_len) == NULL) {
+                ASN1err(ASN1_F_ASN1_ITEM_SIGN_CTX, ERR_R_INTERNAL_ERROR);
+                goto err;
+            }
+        }
 
-    if (pkey->ameth->item_sign) {
+        rv = 3;
+    } else if (pkey->ameth->item_sign) {
         rv = pkey->ameth->item_sign(ctx, it, asn, algor1, algor2, signature);
         if (rv == 1)
             outl = signature->length;
@@ -189,7 +230,7 @@ int ASN1_item_sign_ctx(const ASN1_ITEM *it,
 #ifndef OPENSSL_NO_SM2
             EVP_PKEY_id(pkey) == NID_sm2 ? NID_sm2 :
 #endif
-        pkey->ameth->pkey_id;
+            pkey->ameth->pkey_id;
 
         if (!OBJ_find_sigid_by_algs(&signid, EVP_MD_nid(type), pkey_id)) {
             ASN1err(ASN1_F_ASN1_ITEM_SIGN_CTX,

diff --git a/include/openssl/core_names.h b/include/openssl/core_names.h
index 195fe6ed38ad698dcbd52a699e8b199eb700ca64..20b06ff96b49d9db60282f05abb8a17a6742eeae 100644 (file)
--- a/include/openssl/core_names.h
+++ b/include/openssl/core_names.h
@@ -158,6 +158,8 @@ extern "C" {
 #define OSSL_PKEY_PARAM_BITS                "bits" /* integer */
 #define OSSL_PKEY_PARAM_MAX_SIZE            "max-size" /* integer */
 #define OSSL_PKEY_PARAM_SECURITY_BITS       "security-bits" /* integer */
+#define OSSL_PKEY_PARAM_DIGEST              OSSL_ALG_PARAM_DIGEST
+#define OSSL_PKEY_PARAM_DIGEST_SIZE         "digest-size"
 #define OSSL_PKEY_PARAM_DEFAULT_DIGEST      "default-digest" /* utf8 string */
 #define OSSL_PKEY_PARAM_MANDATORY_DIGEST    "mandatory-digest" /* utf8 string */
 
@@ -200,8 +202,9 @@ extern "C" {
 #define OSSL_EXCHANGE_PARAM_PAD      "pad" /* uint */
 
 /* Signature parameters */
-#define OSSL_SIGNATURE_PARAM_DIGEST         OSSL_ALG_PARAM_DIGEST
-#define OSSL_SIGNATURE_PARAM_DIGEST_SIZE    "digest-size"
+#define OSSL_SIGNATURE_PARAM_ALGORITHM_ID       "algorithm-id"
+#define OSSL_SIGNATURE_PARAM_DIGEST             OSSL_PKEY_PARAM_DIGEST
+#define OSSL_SIGNATURE_PARAM_DIGEST_SIZE        OSSL_PKEY_PARAM_DIGEST_SIZE
 
 /* Asym cipher parameters */
 #define OSSL_ASYM_CIPHER_PARAM_PAD_MODE                 "pad-mode"