diff --git a/wolfcrypt/src/port/kcapi/kcapi_aes.c b/wolfcrypt/src/port/kcapi/kcapi_aes.c
index 4a11a306f..536a955d7 100644
--- a/wolfcrypt/src/port/kcapi/kcapi_aes.c
+++ b/wolfcrypt/src/port/kcapi/kcapi_aes.c
@@ -236,7 +236,9 @@ int wc_AesGcmEncrypt(Aes* aes, byte* out, const byte* in, word32 sz,
     byte*   data = NULL;
     word32  dataSz;
     int     inbuflen = 0, outbuflen = 0;
+#ifndef KCAPI_USE_XMALLOC
     size_t  pageSz = (size_t)sysconf(_SC_PAGESIZE);
+#endif
 
     /* argument checks */
     if (aes == NULL || authTagSz > AES_BLOCK_SIZE) {
@@ -267,11 +269,17 @@ int wc_AesGcmEncrypt(Aes* aes, byte* out, const byte* in, word32 sz,
         outbuflen = (int)kcapi_aead_outbuflen_enc(aes->handle, sz, authInSz,
             authTagSz);
         dataSz = (inbuflen > outbuflen) ? inbuflen : outbuflen;
-
+    #ifdef KCAPI_USE_XMALLOC
+        data = (byte *)XMALLOC(dataSz, aes->heap, DYNAMIC_TYPE_TMP_BUFFER);
+        if (data == NULL) {
+            ret = MEMORY_E;
+        }
+    #else
         ret = posix_memalign((void*)&data, pageSz, dataSz);
         if (ret < 0) {
             ret = MEMORY_E;
         }
+    #endif
     }
 
     if (ret >= 0) {
@@ -312,10 +320,12 @@ int wc_AesGcmEncrypt(Aes* aes, byte* out, const byte* in, word32 sz,
         XMEMCPY(authTag, data + authInSz + sz, authTagSz);
     }
 
-    /* Using free as this is in an environment that will have it
-     * available along with posix_memalign. */
     if (data != NULL) {
+    #ifdef KCAPI_USE_XMALLOC
+        XFREE(data, aes->heap, DYNAMIC_TYPE_TMP_BUFFER);
+    #else
         free(data);
+    #endif
     }
     if (aes != NULL && aes->handle != NULL) {
         kcapi_aead_destroy(aes->handle);
@@ -337,7 +347,9 @@ int wc_AesGcmDecrypt(Aes* aes, byte* out, const byte* in, word32 sz,
     byte*   data = NULL;
     word32  dataSz;
     int     inbuflen = 0, outbuflen = 0;
+#ifndef KCAPI_USE_XMALLOC
     size_t  pageSz = (size_t)sysconf(_SC_PAGESIZE);
+#endif
 
     /* argument checks */
     if (aes == NULL || (sz != 0 && (in == NULL || out == NULL)) ||
@@ -369,11 +381,17 @@ int wc_AesGcmDecrypt(Aes* aes, byte* out, const byte* in, word32 sz,
         outbuflen = (int)kcapi_aead_outbuflen_dec(aes->handle, sz, authInSz,
             authTagSz);
         dataSz = (inbuflen > outbuflen) ? inbuflen : outbuflen;
-
+    #ifdef KCAPI_USE_XMALLOC
+        data = (byte*)XMALLOC(dataSz, aes->heap, DYNAMIC_TYPE_TMP_BUFFER);
+        if (data == NULL) {
+            ret = MEMORY_E;
+        }
+    #else
         ret = posix_memalign((void*)&data, pageSz, dataSz);
         if (ret < 0) {
             ret = MEMORY_E;
         }
+    #endif
     }
 
     if (ret >= 0) {
@@ -413,10 +431,12 @@ int wc_AesGcmDecrypt(Aes* aes, byte* out, const byte* in, word32 sz,
         XMEMCPY(out, data + authInSz, sz);
     }
 
-    /* Using free as this is in an environment that will have it
-     * available along with posix_memalign. */
     if (data != NULL) {
+    #ifdef KCAPI_USE_XMALLOC
+        XFREE(data, aes->heap, DYNAMIC_TYPE_TMP_BUFFER);
+    #else
         free(data);
+    #endif
     }
     if (aes != NULL && aes->handle != NULL) {
         kcapi_aead_destroy(aes->handle);
diff --git a/wolfcrypt/src/port/kcapi/kcapi_ecc.c b/wolfcrypt/src/port/kcapi/kcapi_ecc.c
index 182d06070..4cb0a1c66 100644
--- a/wolfcrypt/src/port/kcapi/kcapi_ecc.c
+++ b/wolfcrypt/src/port/kcapi/kcapi_ecc.c
@@ -204,11 +204,12 @@ int KcapiEcc_SharedSecret(ecc_key* private_key, ecc_key* public_key, byte* out,
 {
     int ret = 0;
     word32 kcapiCurveId = 0;
-    byte* pub_aligned = NULL;
-    byte* out_aligned = NULL;
-    size_t pageSz = (size_t)sysconf(_SC_PAGESIZE);
+    byte* buf_aligned = NULL;
     byte* pub = NULL;
     word32 keySz;
+#ifndef KCAPI_USE_XMALLOC
+    size_t pageSz = (size_t)sysconf(_SC_PAGESIZE);
+#endif
 
     if (private_key == NULL || private_key->dp == NULL || public_key == NULL) {
         ret = BAD_FUNC_ARG;
@@ -242,53 +243,38 @@ int KcapiEcc_SharedSecret(ecc_key* private_key, ecc_key* public_key, byte* out,
         }
     }
     if (ret == 0) {
-        if ((size_t)pub % pageSz != 0) {
-            ret = posix_memalign((void*)&pub_aligned, pageSz, keySz * 2);
-            if (ret == 0) {
-                XMEMCPY(pub_aligned, pub, keySz * 2);
-            }
-            else {
-                ret = MEMORY_E;
-            }
+    #ifdef KCAPI_USE_XMALLOC
+        buf_aligned = (byte*)XMALLOC(keySz * 2, private_key->heap,
+            DYNAMIC_TYPE_TMP_BUFFER);
+        if (buf_aligned == NULL) {
+            ret = MEMORY_E;
         }
-        else {
-            pub_aligned = pub;
+    #else
+        ret = posix_memalign((void*)&buf_aligned, pageSz, keySz * 2);
+        if (ret != 0) {
+            ret = MEMORY_E;
         }
+    #endif
     }
     if (ret == 0) {
-        if ((size_t)out % pageSz != 0) {
-            ret = posix_memalign((void*)&out_aligned, pageSz, keySz * 2);
-            if (ret != 0) {
-                ret = MEMORY_E;
-            }
-        }
-        else {
-            out_aligned = out;
-        }
-    }
+        XMEMCPY(buf_aligned, pub, keySz * 2);
 
-    if (ret == 0) {
-        ret = (int)kcapi_kpp_ssgen(private_key->handle, pub_aligned,
-            keySz * 2, out_aligned, keySz * 2, KCAPI_ACCESS_HEURISTIC);
+        ret = (int)kcapi_kpp_ssgen(private_key->handle, buf_aligned,
+            keySz * 2, buf_aligned, keySz * 2, KCAPI_ACCESS_HEURISTIC);
         if (ret >= 0) {
             *outlen = ret / 2;
-            if (out_aligned != out) {
-                /* don't overflow out */
-                if (ret > (int)*outlen)
-                    ret = (int)*outlen;
-                XMEMCPY(out, out_aligned, ret);
-            }
+            XMEMCPY(out, buf_aligned, *outlen);
+
             ret = 0; /* success */
         }
     }
 
-    /* Using free as this is in an environment that will have it
-     * available along with posix_memalign. */
-    if (pub_aligned != NULL && pub != pub_aligned) {
-        free(pub_aligned);
-    }
-    if (out_aligned != NULL && out != out_aligned) {
-        free(out_aligned);
+    if (buf_aligned != NULL) {
+    #ifdef KCAPI_USE_XMALLOC
+        XFREE(buf_aligned, private_key->heap, DYNAMIC_TYPE_TMP_BUFFER);
+    #else
+        free(buf_aligned);
+    #endif
     }
 
     return ret;
@@ -307,8 +293,18 @@ static int KcapiEcc_SetPrivKey(ecc_key* key)
     if (ret == 0) {
         priv[0] = ECDSA_KEY_VERSION;
         priv[1] = kcapiCurveId;
-        ret = wc_export_int(&key->k, priv + KCAPI_PARAM_SZ, &keySz, keySz,
-                            WC_TYPE_UNSIGNED_BIN);
+    #ifdef WOLF_PRIVATE_KEY_ID
+        if (key->idLen > 0) {
+            WOLFSSL_MSG("Using ID based private key");
+            keySz = key->idLen;
+            XMEMCPY(priv + KCAPI_PARAM_SZ, key->id, keySz);
+        }
+        else
+    #endif
+        {
+            ret = wc_export_int(&key->k, priv + KCAPI_PARAM_SZ, &keySz, keySz,
+                                WC_TYPE_UNSIGNED_BIN);
+        }
     }
     if (ret == 0) {
         /* call with NULL to so KCAPI treats incoming data as hash */
@@ -328,11 +324,13 @@ int KcapiEcc_Sign(ecc_key* key, const byte* hash, word32 hashLen, byte* sig,
                   word32 sigLen)
 {
     int ret = 0;
-    byte* hash_aligned = NULL;
-    byte* sig_aligned = NULL;
-    size_t pageSz = (size_t)sysconf(_SC_PAGESIZE);
+    byte* buf_aligned = NULL;
     int handleInit = 0;
     word32 keySz;
+    word32 maxBufSz;
+#ifndef KCAPI_USE_XMALLOC
+    size_t pageSz = (size_t)sysconf(_SC_PAGESIZE);
+#endif
 
     if (key == NULL || key->dp == NULL) {
         ret = BAD_FUNC_ARG;
@@ -357,48 +355,37 @@ int KcapiEcc_Sign(ecc_key* key, const byte* hash, word32 hashLen, byte* sig,
         }
     }
     if (ret == 0) {
-        if ((size_t)sig % pageSz != 0) {
-            ret = posix_memalign((void*)&sig_aligned, pageSz, keySz * 2);
-            if (ret != 0) {
-                ret = MEMORY_E;
-            }
+        maxBufSz = (hashLen > keySz * 2) ? hashLen : (keySz * 2);
+    #ifdef KCAPI_USE_XMALLOC
+        buf_aligned = (unsigned char*)XMALLOC(maxBufSz, key->heap,
+            DYNAMIC_TYPE_TMP_BUFFER);
+        if (buf_aligned == NULL) {
+            ret = MEMORY_E;
         }
-        else {
-            sig_aligned = sig;
+    #else
+        ret = posix_memalign((void*)&buf_aligned, pageSz, maxBufSz);
+        if (ret != 0) {
+            ret = MEMORY_E;
         }
+    #endif
     }
     if (ret == 0) {
-        if ((size_t)hash % pageSz != 0) {
-            ret = posix_memalign((void*)&hash_aligned, pageSz, hashLen);
-            if (ret == 0) {
-                XMEMCPY(hash_aligned, hash, hashLen);
-            }
-            else {
-                ret = MEMORY_E;
-            }
-        }
-        else {
-            hash_aligned = (byte*)hash;
-        }
-    }
-    if (ret == 0) {
-        ret = (int)kcapi_akcipher_sign(key->handle, hash_aligned, hashLen,
-            sig_aligned, keySz*2, KCAPI_ACCESS_HEURISTIC);
+        XMEMCPY(buf_aligned, hash, hashLen);
+
+        ret = (int)kcapi_akcipher_sign(key->handle, buf_aligned, hashLen,
+            buf_aligned, keySz * 2, KCAPI_ACCESS_HEURISTIC);
         if (ret >= 0) {
-            if (sig_aligned != sig) {
-                XMEMCPY(sig, sig_aligned, ret);
-            }
+            XMEMCPY(sig, buf_aligned, ret);
             ret = 0; /* mark success */
         }
     }
 
-    /* Using free as this is in an environment that will have it
-     * available along with posix_memalign. */
-    if (sig_aligned != NULL && sig != sig_aligned) {
-        free(sig_aligned);
-    }
-    if (hash_aligned != NULL && hash != hash_aligned) {
-        free(hash_aligned);
+    if (buf_aligned != NULL) {
+    #ifdef KCAPI_USE_XMALLOC
+        XFREE(buf_aligned, key->heap, DYNAMIC_TYPE_TMP_BUFFER);
+    #else
+        free(buf_aligned);
+    #endif
     }
 
     if (handleInit) {
@@ -444,11 +431,12 @@ int KcapiEcc_Verify(ecc_key* key, const byte* hash, word32 hashLen, byte* sig,
                     word32 sigLen)
 {
     int ret = 0;
-    byte* sigHash_aligned = NULL;
-    size_t pageSz = (size_t)sysconf(_SC_PAGESIZE);
+    byte* buf_aligned = NULL;
     int handleInit = 0;
     word32 keySz = 0;
-    byte* outbuf = NULL;
+#ifndef KCAPI_USE_XMALLOC
+    size_t pageSz = (size_t)sysconf(_SC_PAGESIZE);
+#endif
 
     if (key == NULL || key->dp == NULL) {
         ret = BAD_FUNC_ARG;
@@ -464,39 +452,40 @@ int KcapiEcc_Verify(ecc_key* key, const byte* hash, word32 hashLen, byte* sig,
             ret = KcapiEcc_SetPubKey(key);
         }
     }
-    if (ret == 0) {
-        ret = posix_memalign((void*)&sigHash_aligned, pageSz, sigLen + hashLen);
-        if (ret != 0) {
-            ret = MEMORY_E;
-        }
-    }
     if (ret == 0) {
         keySz = key->dp->size;
-        ret = posix_memalign((void*)&outbuf, pageSz, keySz * 2);
+    #ifdef KCAPI_USE_XMALLOC
+        buf_aligned = (byte*)XMALLOC(sigLen + hashLen, key->heap,
+            DYNAMIC_TYPE_TMP_BUFFER);
+        if (buf_aligned == NULL) {
+            ret = MEMORY_E;
+        }
+    #else
+        ret = posix_memalign((void*)&buf_aligned, pageSz, sigLen + hashLen);
         if (ret != 0) {
             ret = MEMORY_E;
         }
+    #endif
     }
     if (ret == 0) {
-        XMEMCPY(sigHash_aligned, sig, sigLen);
-        XMEMCPY(sigHash_aligned + sigLen, hash, hashLen);
+        XMEMCPY(buf_aligned, sig, sigLen);
+        XMEMCPY(buf_aligned + sigLen, hash, hashLen);
 
-        ret = (int)kcapi_akcipher_verify(key->handle, sigHash_aligned,
-            sigLen + hashLen, outbuf, keySz * 2,
+        ret = (int)kcapi_akcipher_verify(key->handle, buf_aligned,
+            sigLen + hashLen, buf_aligned, keySz * 2,
             KCAPI_ACCESS_HEURISTIC);
         if (ret >= 0) {
+            /* verify output in buf_aligned is not used */
             ret = 0;
         }
-        (void)outbuf; /* not used */
     }
 
-    /* Using free as this is in an environment that will have it
-     * available along with posix_memalign. */
-    if (sigHash_aligned != NULL) {
-        free(sigHash_aligned);
-    }
-    if (outbuf != NULL) {
-        free(outbuf);
+    if (buf_aligned != NULL) {
+    #ifdef KCAPI_USE_XMALLOC
+        XFREE(buf_aligned, key->heap, DYNAMIC_TYPE_TMP_BUFFER);
+    #else
+        free(buf_aligned);
+    #endif
     }
 
     if (handleInit) {