EVP fetching: make operation_id part of the method identity

Because the operation identity wasn't integrated with the created
methods, the following code would give unexpected results:

    EVP_MD *md = EVP_MD_fetch(NULL, "MD5", NULL);
    EVP_CIPHER *cipher = EVP_CIPHER_fetch(NULL, "MD5", NULL);

    if (md != NULL)
        printf("MD5 is a digest\n");
    if (cipher != NULL)
        printf("MD5 is a cipher\n");

The message is that MD5 is both a digest and a cipher.

Partially fixes #9106

Reviewed-by: Shane Lontis <shane.lontis@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/9109)

2 files changed, 74 insertions, 22 deletions

diff --git a/crypto/core_fetch.c b/crypto/core_fetch.c
index a99f092486..56a3c5cadb 100644
--- a/crypto/core_fetch.c
+++ b/crypto/core_fetch.c
@@ -59,12 +59,12 @@ static int ossl_method_construct_this(OSSL_PROVIDER *provider, void *cbdata)
              * If we haven't been told not to store,
              * add to the global store
              */
-            data->mcm->put(data->libctx, NULL, method,
+            data->mcm->put(data->libctx, NULL, method, data->operation_id,
                            thismap->algorithm_name,
                            thismap->property_definition, data->mcm_data);
         }
 
-        data->mcm->put(data->libctx, data->store, method,
+        data->mcm->put(data->libctx, data->store, method, data->operation_id,
                        thismap->algorithm_name, thismap->property_definition,
                        data->mcm_data);
 
@@ -83,7 +83,8 @@ void *ossl_method_construct(OPENSSL_CTX *libctx, int operation_id,
     void *method = NULL;
 
     if ((method =
-         mcm->get(libctx, NULL, name, propquery, mcm_data)) == NULL) {
+         mcm->get(libctx, NULL, operation_id, name, propquery, mcm_data))
+        == NULL) {
         struct construct_data_st cbdata;
 
         /*
@@ -101,7 +102,8 @@ void *ossl_method_construct(OPENSSL_CTX *libctx, int operation_id,
         ossl_provider_forall_loaded(libctx, ossl_method_construct_this,
                                     &cbdata);
 
-        method = mcm->get(libctx, cbdata.store, name, propquery, mcm_data);
+        method = mcm->get(libctx, cbdata.store, operation_id, name,
+                          propquery, mcm_data);
         mcm->dealloc_tmp_store(cbdata.store);
     }
 
diff --git a/crypto/evp/evp_fetch.c b/crypto/evp/evp_fetch.c
index d3b5bcada2..1c9e27db87 100644
--- a/crypto/evp/evp_fetch.c
+++ b/crypto/evp/evp_fetch.c
@@ -39,7 +39,6 @@ static const OPENSSL_CTX_METHOD default_method_store_method = {
 struct method_data_st {
     OPENSSL_CTX *libctx;
     const char *name;
-    int id;
     OSSL_METHOD_CONSTRUCT_METHOD *mcm;
     void *(*method_from_dispatch)(const OSSL_DISPATCH *, OSSL_PROVIDER *);
     int (*refcnt_up_method)(void *method);
@@ -66,24 +65,45 @@ static OSSL_METHOD_STORE *get_default_method_store(OPENSSL_CTX *libctx)
                                 &default_method_store_method);
 }
 
+/*
+ * To identity the method in the method store, we mix the name identity
+ * with the operation identity, with the assumption that we don't have
+ * more than 2^24 names or more than 2^8 operation types.
+ *
+ * The resulting identity is a 32-bit integer, composed like this:
+ *
+ * +---------24 bits--------+-8 bits-+
+ * |      name identity     | op id  |
+ * +------------------------+--------+
+ */
+static uint32_t method_id(unsigned int operation_id, unsigned int name_id)
+{
+    if (!ossl_assert(name_id < (1 << 24) || operation_id < (1 << 8))
+        || !ossl_assert(name_id > 0 && operation_id > 0))
+        return 0;
+    return ((name_id << 8) & 0xFFFFFF00) | (operation_id & 0x000000FF);
+}
+
 static void *get_method_from_store(OPENSSL_CTX *libctx, void *store,
-                                   const char *name, const char *propquery,
-                                   void *data)
+                                   int operation_id, const char *name,
+                                   const char *propquery, void *data)
 {
     struct method_data_st *methdata = data;
     void *method = NULL;
     OSSL_NAMEMAP *namemap;
-    int id;
+    int nameid;
+    uint32_t methid;
 
     if (store == NULL
         && (store = get_default_method_store(libctx)) == NULL)
         return NULL;
 
     if ((namemap = ossl_namemap_stored(libctx)) == NULL
-        || (id = ossl_namemap_add(namemap, name)) == 0)
+        || (nameid = ossl_namemap_add(namemap, name)) == 0
+        || (methid = method_id(operation_id, nameid)) == 0)
         return NULL;
 
-    (void)ossl_method_store_fetch(store, id, propquery, &method);
+    (void)ossl_method_store_fetch(store, methid, propquery, &method);
 
     if (method != NULL
         && !methdata->refcnt_up_method(method)) {
@@ -93,15 +113,18 @@ static void *get_method_from_store(OPENSSL_CTX *libctx, void *store,
 }
 
 static int put_method_in_store(OPENSSL_CTX *libctx, void *store,
-                               void *method, const char *name,
-                               const char *propdef, void *data)
+                               void *method, int operation_id,
+                               const char *name, const char *propdef,
+                               void *data)
 {
     struct method_data_st *methdata = data;
     OSSL_NAMEMAP *namemap;
-    int id;
+    int nameid;
+    uint32_t methid;
 
     if ((namemap = ossl_namemap_stored(methdata->libctx)) == NULL
-        || (id = ossl_namemap_add(namemap, name)) == 0)
+        || (nameid = ossl_namemap_add(namemap, name)) == 0
+        || (methid = method_id(operation_id, nameid)) == 0)
         return 0;
 
     if (store == NULL
@@ -109,7 +132,7 @@ static int put_method_in_store(OPENSSL_CTX *libctx, void *store,
         return 0;
 
     if (methdata->refcnt_up_method(method)
-        && ossl_method_store_add(store, id, propdef, method,
+        && ossl_method_store_add(store, methid, propdef, method,
                                  methdata->destruct_method))
         return 1;
     return 0;
@@ -139,14 +162,32 @@ void *evp_generic_fetch(OPENSSL_CTX *libctx, int operation_id,
 {
     OSSL_METHOD_STORE *store = get_default_method_store(libctx);
     OSSL_NAMEMAP *namemap = ossl_namemap_stored(libctx);
-    int id;
+    int nameid = 0;
+    uint32_t methid = 0;
     void *method = NULL;
 
     if (store == NULL || namemap == NULL)
         return NULL;
 
-    if ((id = ossl_namemap_number(namemap, name)) == 0
-        || !ossl_method_store_cache_get(store, id, properties, &method)) {
+    /*
+     * If there's ever an operation_id == 0 passed, we have an internal
+     * programming error.
+     */
+    if (!ossl_assert(operation_id > 0))
+        return NULL;
+
+    /*
+     * method_id returns 0 if we have too many operations (more than
+     * about 2^8) or too many names (more than about 2^24).  In that
+     * case, we can't create any new method.
+     */
+    if ((nameid = ossl_namemap_number(namemap, name)) != 0
+        && (methid = method_id(operation_id, nameid)) == 0)
+        return NULL;
+
+    if (nameid == 0
+        || !ossl_method_store_cache_get(store, methid, properties,
+                                        &method)) {
         OSSL_METHOD_CONSTRUCT_METHOD mcm = {
             alloc_tmp_method_store,
             dealloc_tmp_method_store,
@@ -164,10 +205,19 @@ void *evp_generic_fetch(OPENSSL_CTX *libctx, int operation_id,
         mcmdata.destruct_method = free_method;
         mcmdata.refcnt_up_method = upref_method;
         mcmdata.destruct_method = free_method;
-        method = ossl_method_construct(libctx, operation_id, name,
-                                       properties, 0 /* !force_cache */,
-                                       &mcm, &mcmdata);
-        ossl_method_store_cache_set(store, id, properties, method);
+        if ((method = ossl_method_construct(libctx, operation_id, name,
+                                            properties, 0 /* !force_cache */,
+                                            &mcm, &mcmdata)) == NULL) {
+            /*
+             * If construction did create a method for us, we know that
+             * there is a correct nameid and methodid, since those have
+             * already been calculated in get_method_from_store() and
+             * put_method_in_store() above.
+             */
+            nameid = ossl_namemap_number(namemap, name);
+            methid = method_id(operation_id, nameid);
+            ossl_method_store_cache_set(store, methid, properties, method);
+        }
     } else {
         upref_method(method);
     }