2 files changed, 102 insertions, 16 deletions
diff --git a/demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/web/web.c b/demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/web/web.c
index 1907fc633..c0e717b0f 100644
--- a/demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/web/web.c
+++ b/demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/web/web.c
@@ -26,6 +26,8 @@
  * @{
  */
 
+#include <ctype.h>
+
 #include "ch.h"
 
 #include "lwip/opt.h"
@@ -36,6 +38,81 @@
 
 #if LWIP_NETCONN
 
+static char url_buffer[WEB_MAX_PATH_SIZE];
+
+#define HEXTOI(x) (isdigit(x) ? (x) - '0' : (x) - 'a' + 10)
+
+/**
+ * @brief   Decodes an URL sting.
+ * @note    The string is terminated by a zero or a separator.
+ *
+ * @param[in] url       encoded URL string
+ * @param[out] buf      buffer for the processed string
+ * @param[in] max       max number of chars to copy into the buffer
+ * @return              The conversion status.
+ * @retval false        string converted.
+ * @retval true         the string was not valid or the buffer overflowed
+ *
+ * @notapi
+ */
+static bool decode_url(const char *url, char *buf, size_t max) {
+
+  while (true) {
+    int h, l;
+    unsigned c = *url++;
+
+    switch (c) {
+    case 0:
+    case '\r':
+    case '\n':
+    case '\t':
+    case ' ':
+    case '?':
+      *buf = 0;
+      return false;
+    case '.':
+      if (max <= 1)
+        return true;
+
+      h = *(url + 1);
+      if (h == '.')
+        return true;
+
+      break;
+    case '%':
+      if (max <= 1)
+        return true;
+
+      h = tolower((int)*url++);
+      if (h == 0)
+        return true;
+      if (!isxdigit(h))
+        return true;
+
+      l = tolower((int)*url++);
+      if (l == 0)
+        return true;
+      if (!isxdigit(l))
+        return true;
+
+      c = (char)((HEXTOI(h) << 4) | HEXTOI(l));
+      break;
+    default:
+      if (max <= 1)
+        return true;
+
+      if (!isalnum(c) && (c != '_') && (c != '-') && (c != '+') &&
+          (c != '/'))
+        return true;
+
+      break;
+    }
+
+    *buf++ = c;
+    max--;
+  }
+}
+
 static const char http_html_hdr[] = "HTTP/1.1 200 OK\r\nContent-type: text/html\r\n\r\n";
 static const char http_index_html[] = "<html><head><title>Congrats!</title></head><body><h1>Welcome to our lwIP HTTP server!</h1><p>This is a small test page.</body></html>";
 
@@ -46,20 +123,25 @@ static void http_server_serve(struct netconn *conn) {
   err_t err;
 
   /* Read the data from the port, blocking if nothing yet there.
-   We assume the request (the part we care about) is in one netbuf */
+     We assume the request (the part we care about) is in one netbuf.*/
   err = netconn_recv(conn, &inbuf);
 
   if (err == ERR_OK) {
     netbuf_data(inbuf, (void **)&buf, &buflen);
 
     /* Is this an HTTP GET command? (only check the first 5 chars, since
-    there are other formats for GET, and we're keeping it very simple )*/
-    if (buflen>=5 &&
-        buf[0]=='G' &&
-        buf[1]=='E' &&
-        buf[2]=='T' &&
-        buf[3]==' ' &&
-        buf[4]=='/' ) {
+       there are other formats for GET, and we're keeping it very simple ).*/
+    if (buflen >= 5 &&
+        buf[0] == 'G' &&
+        buf[1] == 'E' &&
+        buf[2] == 'T' &&
+        buf[3] == ' ' &&
+        buf[4] == '/') {
+
+      if (decode_url(buf + 4, url_buffer, WEB_MAX_PATH_SIZE)) {
+        /* Invalid URL handling.*/
+        return;
+      }
 
       /* Send the HTML header
              * subtract 1 from the size, since we dont send the \0 in the string
@@ -80,12 +162,12 @@ static void http_server_serve(struct netconn *conn) {
 }
 
 /**
- * Stack area for the http thread.
+ * @brief   Stack area for the http thread.
  */
 THD_WORKING_AREA(wa_http_server, WEB_THREAD_STACK_SIZE);
 
 /**
- * HTTP server thread.
+ * @brief   HTTP server thread.
  */
 THD_FUNCTION(http_server, p) {
   struct netconn *conn, *newconn;
diff --git a/demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/web/web.h b/demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/web/web.h
index 902bf9be4..946576b8d 100644
--- a/demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/web/web.h
+++ b/demos/STM32/RT-STM32F746G-DISCOVERY-LWIP-FATFS-USB/web/web.h
@@ -24,16 +24,20 @@
 #ifndef _WEB_H_
 #define _WEB_H_
 
-#ifndef WEB_THREAD_STACK_SIZE
-#define WEB_THREAD_STACK_SIZE   1024
+#if !defined(WEB_THREAD_STACK_SIZE)
+#define WEB_THREAD_STACK_SIZE           1024
 #endif
 
-#ifndef WEB_THREAD_PORT
-#define WEB_THREAD_PORT         80
+#if !defined(WEB_THREAD_PORT)
+#define WEB_THREAD_PORT                 80
 #endif
 
-#ifndef WEB_THREAD_PRIORITY
-#define WEB_THREAD_PRIORITY     (LOWPRIO + 2)
+#if !defined(WEB_THREAD_PRIORITY)
+#define WEB_THREAD_PRIORITY             (LOWPRIO + 2)
+#endif
+
+#if !defined(WEB_MAX_PATH_SIZE)
+#define WEB_MAX_PATH_SIZE               128
 #endif
 
 extern THD_WORKING_AREA(wa_http_server, WEB_THREAD_STACK_SIZE);