io: refactoring EmbedOcspLookup:

--- single return point
--- changed stack reduction MEMORY_E to -1 to match XMALLOC fail at httpBuf
--- variable written removed
--- variable ocspRespSz renamed to ret (initialized with -1  and set only once with process_http_response result)

src/io.c

@@ -836,11 +836,9 @@ static int process_http_response(int sfd, byte** respBuf,
 int EmbedOcspLookup(void* ctx, const char* url, int urlSz,
                         byte* ocspReqBuf, int ocspReqSz, byte** ocspRespBuf)
 {
-    int httpBufSz;
     SOCKET_T sfd = 0;
     word16   port;
-    int ocspRespSz = 0;
+    int      ret = -1;
-    byte* httpBuf = NULL;
 #ifdef CYASSL_SMALL_STACK
     char*    path;
     char*    domainName;
@@ -849,94 +847,70 @@ int EmbedOcspLookup(void* ctx, const char* url, int urlSz,
     char     domainName[80];
 #endif
 
-    (void)ctx;
-
-    if (ocspReqBuf == NULL || ocspReqSz == 0) {
-        CYASSL_MSG("OCSP request is required for lookup");
-        return -1;
-    }
-
-    if (ocspRespBuf == NULL) {
-        CYASSL_MSG("Cannot save OCSP response");
-        return -1;
-    }
-
 #ifdef CYASSL_SMALL_STACK
     path = (char*)XMALLOC(80, NULL, DYNAMIC_TYPE_TMP_BUFFER);
     if (path == NULL)
-        return MEMORY_E;
+        return -1;
     
     domainName = (char*)XMALLOC(80, NULL, DYNAMIC_TYPE_TMP_BUFFER);
     if (domainName == NULL) {
         XFREE(path, NULL, DYNAMIC_TYPE_TMP_BUFFER);
-        return MEMORY_E;
-    }
-#endif
-
-    if (decode_url(url, urlSz, domainName, path, &port) < 0) {
-        CYASSL_MSG("Unable to decode OCSP URL");
-#ifdef CYASSL_SMALL_STACK
-        XFREE(path,       NULL, DYNAMIC_TYPE_TMP_BUFFER);
-        XFREE(domainName, NULL, DYNAMIC_TYPE_TMP_BUFFER);
-#endif
         return -1;
     }
+#endif
 
+    (void)ctx;
+
+    if (ocspReqBuf == NULL || ocspReqSz == 0) {
+        CYASSL_MSG("OCSP request is required for lookup");
+    }
+    else if (ocspRespBuf == NULL) {
+        CYASSL_MSG("Cannot save OCSP response");
+    }
+    else if (decode_url(url, urlSz, domainName, path, &port) < 0) {
+        CYASSL_MSG("Unable to decode OCSP URL");
+    }
+    else {
         /* Note, the library uses the EmbedOcspRespFree() callback to
          * free this buffer. */
-    httpBufSz = SCRATCH_BUFFER_SIZE;
+        int   httpBufSz = SCRATCH_BUFFER_SIZE;
-    httpBuf = (byte*)XMALLOC(httpBufSz, NULL, DYNAMIC_TYPE_IN_BUFFER);
+        byte* httpBuf   = (byte*)XMALLOC(httpBufSz, NULL, 
+                                                        DYNAMIC_TYPE_IN_BUFFER);
 
         if (httpBuf == NULL) {
             CYASSL_MSG("Unable to create OCSP response buffer");
-#ifdef CYASSL_SMALL_STACK
-        XFREE(path,       NULL, DYNAMIC_TYPE_TMP_BUFFER);
-        XFREE(domainName, NULL, DYNAMIC_TYPE_TMP_BUFFER);
-#endif
-        return -1;
         }
-
+        else {
             httpBufSz = build_http_request(domainName, path, ocspReqSz,
                                                             httpBuf, httpBufSz);
 
-    if ((tcp_connect(&sfd, domainName, port) == 0) && (sfd > 0)) {
+            if ((tcp_connect(&sfd, domainName, port) != 0) || (sfd <= 0)) {
-        int written;
-        written = (int)send(sfd, (char*)httpBuf, httpBufSz, 0);
-        if (written == httpBufSz) {
-            written = (int)send(sfd, (char*)ocspReqBuf, ocspReqSz, 0);
-            if (written == ocspReqSz) {
-                ocspRespSz = process_http_response(sfd, ocspRespBuf,
-                                                 httpBuf, SCRATCH_BUFFER_SIZE);
-            }
-        }
-        close(sfd);
-        if (ocspRespSz == 0) {
-            CYASSL_MSG("OCSP response was not OK, no OCSP response");
-            XFREE(httpBuf,    NULL, DYNAMIC_TYPE_IN_BUFFER);
-#ifdef CYASSL_SMALL_STACK
-            XFREE(path,       NULL, DYNAMIC_TYPE_TMP_BUFFER);
-            XFREE(domainName, NULL, DYNAMIC_TYPE_TMP_BUFFER);
-#endif
-            return -1;
-        }
-    } else {
                 CYASSL_MSG("OCSP Responder connection failed");
-        close(sfd);
+            }
-        XFREE(httpBuf,    NULL, DYNAMIC_TYPE_IN_BUFFER);
+            else if ((int)send(sfd, (char*)httpBuf, httpBufSz, 0) !=
-#ifdef CYASSL_SMALL_STACK
+                                                                    httpBufSz) {
-        XFREE(path,       NULL, DYNAMIC_TYPE_TMP_BUFFER);
+                CYASSL_MSG("OCSP http request failed");
-        XFREE(domainName, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+            }
-#endif
+            else if ((int)send(sfd, (char*)ocspReqBuf, ocspReqSz, 0) !=
-        return -1;
+                                                                    ocspReqSz) {
+                CYASSL_MSG("OCSP ocsp request failed");
+            }
+            else {
+                ret = process_http_response(sfd, ocspRespBuf, httpBuf,
+                                                           SCRATCH_BUFFER_SIZE);
             }
 
+            close(sfd);
             XFREE(httpBuf, NULL, DYNAMIC_TYPE_IN_BUFFER);
+        }
+    }
+
 #ifdef CYASSL_SMALL_STACK
     XFREE(path,       NULL, DYNAMIC_TYPE_TMP_BUFFER);
     XFREE(domainName, NULL, DYNAMIC_TYPE_TMP_BUFFER);
 #endif
 
-    return ocspRespSz;
+    return ret;
 }