Peer review fixes

Author: dgarske

examples/keygen/keygen.c

@@ -297,27 +297,10 @@ int TPM2_Keygen_Example(void* userCtx, int argc, char *argv[])
                      XSTRLEN("-paramkey=")) == 0) {
             /* Choose a PQC key for the param-enc session (separate from the
              * child key -mlkem/-mldsa selection above). Value is e.g.
-             * "mlkem", "mlkem=768", "mldsa" or "mldsa=65". */
+             * "mlkem", "mlkem=768", "mldsa" or "mldsa=65". Reuses the shared
+             * value-form parser so validation stays consistent. */
             const char* pkVal = argv[argc-1] + XSTRLEN("-paramkey=");
-        #ifdef WOLFTPM_MLKEM
-            if (XSTRNCMP(pkVal, "mlkem", 5) == 0) {
-                int n = (pkVal[5] == '=') ? XATOI(&pkVal[6]) : 768;
-                pqcParamEncAlg = TPM_ALG_MLKEM;
-                pqcParamSet = (n == 512) ? TPM_MLKEM_512 :
-                              (n == 1024) ? TPM_MLKEM_1024 : TPM_MLKEM_768;
-            }
-            else
-        #endif
-        #ifdef WOLFTPM_MLDSA
-            if (XSTRNCMP(pkVal, "mldsa", 5) == 0) {
-                int n = (pkVal[5] == '=') ? XATOI(&pkVal[6]) : 65;
-                pqcParamEncAlg = TPM_ALG_MLDSA;
-                pqcParamSet = (n == 44) ? TPM_MLDSA_44 :
-                              (n == 87) ? TPM_MLDSA_87 : TPM_MLDSA_65;
-            }
-            else
-        #endif
-            {
+            if (!parsePqcParamSet(pkVal, &pqcParamEncAlg, &pqcParamSet)) {
                 printf("Invalid -paramkey value: %s\n", pkVal);
                 usage();
                 return 0;

examples/tpm_test_keys.c

@@ -503,32 +503,58 @@ int getPrimaryParamEncKey(WOLFTPM2_DEV* pDev, WOLFTPM2_SESSION* session,
     return rc;
 }
 
-int parsePqcParamEncArg(const char* arg, TPM_ALG_ID* alg, int* paramSet)
+int parsePqcParamSet(const char* val, TPM_ALG_ID* alg, int* paramSet)
 {
-    if (arg == NULL || alg == NULL || paramSet == NULL)
+    int n;
+
+    if (val == NULL || alg == NULL || paramSet == NULL)
         return 0;
 #ifdef WOLFTPM_MLKEM
-    if (XSTRCMP(arg, "-mlkem") == 0 ||
-            XSTRNCMP(arg, "-mlkem=", 7) == 0) {
-        int n = (arg[6] == '=') ? XATOI(&arg[7]) : 768;
+    if (XSTRCMP(val, "mlkem") == 0 ||
+            XSTRNCMP(val, "mlkem=", 6) == 0) {
+        n = (val[5] == '=') ? XATOI(&val[6]) : 768;
         *alg = TPM_ALG_MLKEM;
-        *paramSet = (n == 512) ? TPM_MLKEM_512 :
-                    (n == 1024) ? TPM_MLKEM_1024 : TPM_MLKEM_768;
+        if (n == 512)
+            *paramSet = TPM_MLKEM_512;
+        else if (n == 768)
+            *paramSet = TPM_MLKEM_768;
+        else if (n == 1024)
+            *paramSet = TPM_MLKEM_1024;
+        else {
+            printf("Invalid ML-KEM parameter set: %d (use 512, 768, or 1024)\n",
+                n);
+            return 0;
+        }
         return 1;
     }
 #endif
 #ifdef WOLFTPM_MLDSA
-    if (XSTRCMP(arg, "-mldsa") == 0 ||
-            XSTRNCMP(arg, "-mldsa=", 7) == 0) {
-        int n = (arg[6] == '=') ? XATOI(&arg[7]) : 65;
+    if (XSTRCMP(val, "mldsa") == 0 ||
+            XSTRNCMP(val, "mldsa=", 6) == 0) {
+        n = (val[5] == '=') ? XATOI(&val[6]) : 65;
         *alg = TPM_ALG_MLDSA;
-        *paramSet = (n == 44) ? TPM_MLDSA_44 :
-                    (n == 87) ? TPM_MLDSA_87 : TPM_MLDSA_65;
+        if (n == 44)
+            *paramSet = TPM_MLDSA_44;
+        else if (n == 65)
+            *paramSet = TPM_MLDSA_65;
+        else if (n == 87)
+            *paramSet = TPM_MLDSA_87;
+        else {
+            printf("Invalid ML-DSA parameter set: %d (use 44, 65, or 87)\n", n);
+            return 0;
+        }
         return 1;
     }
 #endif
     return 0;
 }
+
+int parsePqcParamEncArg(const char* arg, TPM_ALG_ID* alg, int* paramSet)
+{
+    if (arg == NULL || arg[0] != '-')
+        return 0;
+    return parsePqcParamSet(arg + 1, alg, paramSet);
+}
 #endif /* WOLFTPM_MLDSA || WOLFTPM_MLKEM */
 
 int getRSAkey(WOLFTPM2_DEV* pDev, WOLFTPM2_KEY* pStorageKey, WOLFTPM2_KEY* key,

examples/tpm_test_keys.h

@@ -66,9 +66,18 @@ WOLFTPM_LOCAL int getPrimaryParamEncKey(WOLFTPM2_DEV* pDev,
                                         int paramSet,
                                         int paramEncAlg);
 
+/* Parse a PQC parameter-set value (no leading dash): "mlkem[=512|768|1024]"
+ * or "mldsa[=44|65|87]". On match sets *alg (TPM_ALG_MLKEM / TPM_ALG_MLDSA)
+ * and *paramSet and returns 1. Returns 0 if the value is not recognized, or
+ * if a parameter set is given but is not a supported value (a message is
+ * printed in that case). */
+WOLFTPM_LOCAL int parsePqcParamSet(const char* val, TPM_ALG_ID* alg,
+                                   int* paramSet);
+
 /* Parse a PQC parameter-encryption key option: "-mlkem[=512|768|1024]"
  * (salt) or "-mldsa[=44|65|87]" (bind). On match sets *alg (TPM_ALG_MLKEM /
- * TPM_ALG_MLDSA) and *paramSet and returns 1; returns 0 if not recognized. */
+ * TPM_ALG_MLDSA) and *paramSet and returns 1; returns 0 if not recognized or
+ * if an unsupported parameter set is given. Wraps parsePqcParamSet(). */
 WOLFTPM_LOCAL int parsePqcParamEncArg(const char* arg, TPM_ALG_ID* alg,
                                       int* paramSet);
 #endif

src/tpm2_param_enc.c

@@ -208,7 +208,13 @@ static TPM2B_AUTH* TPM2_ParamEncBindKey(TPM2_AUTH_SESSION* session)
      * the session key). In every other case - a secondary encrypt-only
      * session (name.size 0), or a session authorizing a different entity
      * (whose authValue, if any, is already in session->auth, including the
-     * empty-auth case) - the bind authValue must not be added. */
+     * empty-auth case) - the bind authValue must not be added.
+     * The size test uses <= (not ==) deliberately: in the realistic case the
+     * lone session key is exactly one digest, but <= is kept as a defensive
+     * lower bound so a bound-own-entity session is still admitted even if the
+     * session key is shorter than a full digest. A session authorizing a
+     * different entity always has auth.size strictly greater than the digest
+     * (sessionKey || entityAuth) and so remains excluded either way. */
     if (session->bind != NULL && digestSz > 0 &&
             session->name.size > 0 &&
             session->name.size == session->bindName.size &&

wolftpm/tpm2.h

@@ -1992,7 +1992,9 @@ typedef struct TPM2_AUTH_SESSION {
      * authorization session is authorizing its own bind entity, so the bind
      * authValue is folded into the parameter-encryption key only in that case
      * (TPM 2.0 Part 1: the param-enc key is the session key concatenated with
-     * the authValue of the entity the session authorizes). */
+     * the authValue of the entity the session authorizes).
+     * Placed at the end of the struct so the offsets of existing members are
+     * unchanged; the size growth is covered by the 4.0.0 major version. */
     TPM2B_NAME bindName;
 } TPM2_AUTH_SESSION;