Fix EVP_PKEY_CTX_add1_hkdf_info() behavior

Fix #23448

`EVP_PKEY_CTX_add1_hkdf_info()` behaves like a `set1` function.

Fix the setting of the parameter in the params code.
Update the TLS_PRF code to also use the params code.
Add tests.

Reviewed-by: Shane Lontis <shane.lontis@oracle.com>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/23456)

2 files changed, 50 insertions, 0 deletions

diff --git a/providers/implementations/exchange/kdf_exch.c b/providers/implementations/exchange/kdf_exch.c
index 4aaf673398..84ff369db4 100644
--- a/providers/implementations/exchange/kdf_exch.c
+++ b/providers/implementations/exchange/kdf_exch.c
@@ -28,9 +28,13 @@ static OSSL_FUNC_keyexch_derive_fn kdf_derive;
 static OSSL_FUNC_keyexch_freectx_fn kdf_freectx;
 static OSSL_FUNC_keyexch_dupctx_fn kdf_dupctx;
 static OSSL_FUNC_keyexch_set_ctx_params_fn kdf_set_ctx_params;
+static OSSL_FUNC_keyexch_get_ctx_params_fn kdf_get_ctx_params;
 static OSSL_FUNC_keyexch_settable_ctx_params_fn kdf_tls1_prf_settable_ctx_params;
 static OSSL_FUNC_keyexch_settable_ctx_params_fn kdf_hkdf_settable_ctx_params;
 static OSSL_FUNC_keyexch_settable_ctx_params_fn kdf_scrypt_settable_ctx_params;
+static OSSL_FUNC_keyexch_gettable_ctx_params_fn kdf_tls1_prf_gettable_ctx_params;
+static OSSL_FUNC_keyexch_gettable_ctx_params_fn kdf_hkdf_gettable_ctx_params;
+static OSSL_FUNC_keyexch_gettable_ctx_params_fn kdf_scrypt_gettable_ctx_params;
 
 typedef struct {
     void *provctx;
@@ -169,6 +173,13 @@ static int kdf_set_ctx_params(void *vpkdfctx, const OSSL_PARAM params[])
     return EVP_KDF_CTX_set_params(pkdfctx->kdfctx, params);
 }
 
+static int kdf_get_ctx_params(void *vpkdfctx, OSSL_PARAM params[])
+{
+    PROV_KDF_CTX *pkdfctx = (PROV_KDF_CTX *)vpkdfctx;
+
+    return EVP_KDF_CTX_get_params(pkdfctx->kdfctx, params);
+}
+
 static const OSSL_PARAM *kdf_settable_ctx_params(ossl_unused void *vpkdfctx,
                                                  void *provctx,
                                                  const char *kdfname)
@@ -197,6 +208,34 @@ KDF_SETTABLE_CTX_PARAMS(tls1_prf, "TLS1-PRF")
 KDF_SETTABLE_CTX_PARAMS(hkdf, "HKDF")
 KDF_SETTABLE_CTX_PARAMS(scrypt, "SCRYPT")
 
+static const OSSL_PARAM *kdf_gettable_ctx_params(ossl_unused void *vpkdfctx,
+                                                 void *provctx,
+                                                 const char *kdfname)
+{
+    EVP_KDF *kdf = EVP_KDF_fetch(PROV_LIBCTX_OF(provctx), kdfname,
+                                 NULL);
+    const OSSL_PARAM *params;
+
+    if (kdf == NULL)
+        return NULL;
+
+    params = EVP_KDF_gettable_ctx_params(kdf);
+    EVP_KDF_free(kdf);
+
+    return params;
+}
+
+#define KDF_GETTABLE_CTX_PARAMS(funcname, kdfname) \
+    static const OSSL_PARAM *kdf_##funcname##_gettable_ctx_params(void *vpkdfctx, \
+                                                                  void *provctx) \
+    { \
+        return kdf_gettable_ctx_params(vpkdfctx, provctx, kdfname); \
+    }
+
+KDF_GETTABLE_CTX_PARAMS(tls1_prf, "TLS1-PRF")
+KDF_GETTABLE_CTX_PARAMS(hkdf, "HKDF")
+KDF_GETTABLE_CTX_PARAMS(scrypt, "SCRYPT")
+
 #define KDF_KEYEXCH_FUNCTIONS(funcname) \
     const OSSL_DISPATCH ossl_kdf_##funcname##_keyexch_functions[] = { \
         { OSSL_FUNC_KEYEXCH_NEWCTX, (void (*)(void))kdf_##funcname##_newctx }, \
@@ -205,8 +244,11 @@ KDF_SETTABLE_CTX_PARAMS(scrypt, "SCRYPT")
         { OSSL_FUNC_KEYEXCH_FREECTX, (void (*)(void))kdf_freectx }, \
         { OSSL_FUNC_KEYEXCH_DUPCTX, (void (*)(void))kdf_dupctx }, \
         { OSSL_FUNC_KEYEXCH_SET_CTX_PARAMS, (void (*)(void))kdf_set_ctx_params }, \
+        { OSSL_FUNC_KEYEXCH_GET_CTX_PARAMS, (void (*)(void))kdf_get_ctx_params }, \
         { OSSL_FUNC_KEYEXCH_SETTABLE_CTX_PARAMS, \
         (void (*)(void))kdf_##funcname##_settable_ctx_params }, \
+        { OSSL_FUNC_KEYEXCH_GETTABLE_CTX_PARAMS, \
+        (void (*)(void))kdf_##funcname##_gettable_ctx_params }, \
         OSSL_DISPATCH_END \
     };
 
diff --git a/providers/implementations/kdfs/hkdf.c b/providers/implementations/kdfs/hkdf.c
index a83e298227..a634216419 100644
--- a/providers/implementations/kdfs/hkdf.c
+++ b/providers/implementations/kdfs/hkdf.c
@@ -316,6 +316,13 @@ static int kdf_hkdf_get_ctx_params(void *vctx, OSSL_PARAM params[])
             return 0;
         return OSSL_PARAM_set_size_t(p, sz);
     }
+    if ((p = OSSL_PARAM_locate(params, OSSL_KDF_PARAM_INFO)) != NULL) {
+        if (ctx->info == NULL || ctx->info_len == 0) {
+            p->return_size = 0;
+            return 1;
+        }
+        return OSSL_PARAM_set_octet_string(p, ctx->info, ctx->info_len);
+    }
     return -2;
 }
 
@@ -324,6 +331,7 @@ static const OSSL_PARAM *kdf_hkdf_gettable_ctx_params(ossl_unused void *ctx,
 {
     static const OSSL_PARAM known_gettable_ctx_params[] = {
         OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE, NULL),
+        OSSL_PARAM_octet_string(OSSL_KDF_PARAM_INFO, NULL, 0),
         OSSL_PARAM_END
     };
     return known_gettable_ctx_params;