make EmbedGenerateCookie a callback, USER_IO can install their own or default to ours

cyassl/internal.h

@@ -884,18 +884,18 @@ int  SetCipherList(Suites*, const char* list);
         CYASSL_LOCAL
         void EmbedOcspRespFree(void*, byte*);
     #endif
-#endif
 
-#ifdef CYASSL_DTLS
+    #ifdef CYASSL_DTLS
-    CYASSL_LOCAL
+        CYASSL_LOCAL
-    int EmbedReceiveFrom(CYASSL *ssl, char *buf, int sz, void *ctx);
+        int EmbedReceiveFrom(CYASSL *ssl, char *buf, int sz, void *ctx);
-    CYASSL_LOCAL 
+        CYASSL_LOCAL 
-    int EmbedSendTo(CYASSL *ssl, char *buf, int sz, void *ctx);
+        int EmbedSendTo(CYASSL *ssl, char *buf, int sz, void *ctx);
-    CYASSL_LOCAL
+        CYASSL_LOCAL
-    int EmbedGenerateCookie(byte *buf, int sz, void *ctx);
+        int EmbedGenerateCookie(CYASSL* ssl, byte *buf, int sz, void *ctx);
-    CYASSL_LOCAL
+        CYASSL_LOCAL
-    int IsUDP(void*);
+        int IsUDP(void*);
-#endif
+    #endif /* CYASSL_DTLS */
+#endif /* CYASSL_USER_IO */
 
 
 /* CyaSSL Cipher type just points back to SSL */
@@ -1089,6 +1089,9 @@ struct CYASSL_CTX {
     byte        groupMessages;    /* group handshake messages before sending */
     CallbackIORecv CBIORecv;
     CallbackIOSend CBIOSend;
+#ifdef CYASSL_DTLS
+    CallbackGenCookie CBIOCookie;       /* gen cookie callback */
+#endif
     VerifyCallback  verifyCallback;     /* cert verification callback */
     word32          timeout;            /* session timeout */
 #ifdef HAVE_ECC
@@ -1623,6 +1626,7 @@ struct CYASSL {
     int             dtls_timeout;
     DtlsPool*       dtls_pool;
     DtlsMsg*        dtls_msg_list;
+    void*           IOCB_CookieCtx;     /* gen cookie ctx */
 #endif
 #ifdef CYASSL_CALLBACKS
     HandShakeInfo   handShakeInfo;      /* info saved during handshake */

cyassl/ssl.h

@@ -809,6 +809,11 @@ CYASSL_API void CyaSSL_SetIOWriteCtx(CYASSL* ssl, void *ctx);
 CYASSL_API void CyaSSL_SetIOReadFlags( CYASSL* ssl, int flags);
 CYASSL_API void CyaSSL_SetIOWriteFlags(CYASSL* ssl, int flags);
 
+typedef int (*CallbackGenCookie)(CYASSL* ssl, unsigned char* buf, int sz,
+                                 void* ctx);
+CYASSL_API void CyaSSL_CTX_SetGenCookie(CYASSL_CTX*, CallbackGenCookie);
+CYASSL_API void CyaSSL_SetCookieCtx(CYASSL* ssl, void *ctx);
+
 typedef int (*CallbackIOOcsp)(void*, const char*, int,
                                          unsigned char*, int, unsigned char**);
 typedef void (*CallbackIOOcspRespFree)(void*,unsigned char*); 

src/internal.c

@@ -367,14 +367,16 @@ int InitSSL_Ctx(CYASSL_CTX* ctx, CYASSL_METHOD* method)
     #ifdef CYASSL_DTLS
         if (method->version.major == DTLS_MAJOR
                                   && method->version.minor >= DTLSv1_2_MINOR) {
-            ctx->CBIORecv = EmbedReceiveFrom;
+            ctx->CBIORecv   = EmbedReceiveFrom;
-            ctx->CBIOSend = EmbedSendTo;
+            ctx->CBIOSend   = EmbedSendTo;
+            ctx->CBIOCookie = EmbedGenerateCookie;
         }
     #endif
 #else
     /* user will set */
-    ctx->CBIORecv = NULL;
+    ctx->CBIORecv   = NULL;
-    ctx->CBIOSend = NULL;
+    ctx->CBIOSend   = NULL;
+    ctx->CBIOCookie = NULL;
 #endif
     ctx->partialWrite   = 0;
     ctx->verifyCallback = 0;
@@ -1227,6 +1229,9 @@ int InitSSL(CYASSL* ssl, CYASSL_CTX* ctx)
 
     ssl->IOCB_ReadCtx  = &ssl->rfd;  /* prevent invalid pointer access if not */
     ssl->IOCB_WriteCtx = &ssl->wfd;  /* correctly set */
+#ifdef CYASSL_DTLS
+    ssl->IOCB_CookieCtx = NULL;      /* we don't use for default cb */
+#endif
 
 #ifndef NO_OLD_TLS
 #ifndef NO_MD5
@@ -2196,6 +2201,11 @@ static int Receive(CYASSL* ssl, byte* buf, word32 sz)
 {
     int recvd;
 
+    if (ssl->ctx->CBIORecv == NULL) {
+        CYASSL_MSG("Your IO Recv callback is null, please set");
+        return -1;
+    }
+
 retry:
     recvd = ssl->ctx->CBIORecv(ssl, (char *)buf, (int)sz, ssl->IOCB_ReadCtx);
     if (recvd < 0)
@@ -2290,6 +2300,11 @@ void ShrinkInputBuffer(CYASSL* ssl, int forcedFree)
 
 int SendBuffered(CYASSL* ssl)
 {
+    if (ssl->ctx->CBIOSend == NULL) {
+        CYASSL_MSG("Your IO Send callback is null, please set");
+        return SOCKET_ERROR_E;
+    }
+
     while (ssl->buffers.outputBuffer.length > 0) {
         int sent = ssl->ctx->CBIOSend(ssl,
                                       (char*)ssl->buffers.outputBuffer.buffer +
@@ -9016,8 +9031,12 @@ int SetCipherList(Suites* s, const char* list)
                         return BUFFER_ERROR;
                     if (i + b > totalSz)
                         return INCOMPLETE_DATA;
-                    if ((EmbedGenerateCookie(cookie, COOKIE_SZ, ssl)
+                    if (ssl->ctx->CBIORecv == NULL) {
-                                                                 != COOKIE_SZ)
+                        CYASSL_MSG("Your Cookie callback is null, please set");
+                        return COOKIE_ERROR;
+                    }
+                    if ((ssl->ctx->CBIOCookie(ssl, cookie, COOKIE_SZ,
+                                              ssl->IOCB_CookieCtx) != COOKIE_SZ)
                             || (b != COOKIE_SZ)
                             || (XMEMCMP(cookie, input + i, b) != 0)) {
                         return COOKIE_ERROR;
@@ -9327,7 +9346,12 @@ int SetCipherList(Suites* s, const char* list)
         output[idx++] =  ssl->chVersion.minor;
 
         output[idx++] = cookieSz;
-        if ((ret = EmbedGenerateCookie(output + idx, cookieSz, ssl)) < 0)
+        if (ssl->ctx->CBIORecv == NULL) {
+            CYASSL_MSG("Your Cookie callback is null, please set");
+            return COOKIE_ERROR;
+        }
+        if ((ret = ssl->ctx->CBIOCookie(ssl, output + idx, cookieSz,
+                                        ssl->IOCB_CookieCtx)) < 0)
             return ret;
 
         HashOutput(ssl, output, sendSz, 0);

src/io.c

@@ -429,9 +429,8 @@ int EmbedSendTo(CYASSL* ssl, char *buf, int sz, void *ctx)
 /* The DTLS Generate Cookie callback
  *  return : number of bytes copied into buf, or error
  */
-int EmbedGenerateCookie(byte *buf, int sz, void *ctx)
+int EmbedGenerateCookie(CYASSL* ssl, byte *buf, int sz, void *ctx)
 {
-    CYASSL* ssl = (CYASSL*)ctx;
     int sd = ssl->wfd;
     struct sockaddr_in peer;
     XSOCKLENT peerSz = sizeof(peer);
@@ -439,6 +438,8 @@ int EmbedGenerateCookie(byte *buf, int sz, void *ctx)
     int cookieSrcSz = 0;
     Sha sha;
 
+    (void)ctx;
+
     if (getpeername(sd, (struct sockaddr*)&peer, &peerSz) != 0) {
         CYASSL_MSG("getpeername failed in EmbedGenerateCookie");
         return GEN_COOKIE_E;
@@ -783,6 +784,23 @@ CYASSL_API void CyaSSL_SetIOWriteFlags(CYASSL* ssl, int flags)
     ssl->wflags = flags;
 }
 
+
+#ifdef CYASSL_DTLS
+
+CYASSL_API void CyaSSL_CTX_SetGenCookie(CYASSL_CTX* ctx, CallbackGenCookie cb)
+{
+    ctx->CBIOCookie = cb;
+}
+
+
+CYASSL_API void CyaSSL_SetCookieCtx(CYASSL* ssl, void *ctx)
+{
+	ssl->IOCB_CookieCtx = ctx;
+}
+
+#endif /* CYASSL_DTLS */
+
+
 #ifdef HAVE_OCSP
 
 CYASSL_API void CyaSSL_SetIOOcsp(CYASSL_CTX* ctx, CallbackIOOcsp cb)