Stop sending retransmitted received blocks up to client

Fixed handling of retransmitted blocks on transmit
Properly aligned data to transmit within packet
Replaced calls to strerror() with Curl_strerror()

1 files changed, 30 insertions, 14 deletions

diff --git a/lib/tftp.c b/lib/tftp.c
index 780cceea5..078dcfd8c 100644
--- a/lib/tftp.c
+++ b/lib/tftp.c
@@ -86,6 +86,9 @@
 /* The last #include file should be: */
 #include "memdebug.h"
 
+/* RFC2348 allows the block size to be negotiated, but we don't support that */
+#define TFTP_BLOCKSIZE 512
+
 typedef enum {
   TFTP_MODE_NETASCII=0,
   TFTP_MODE_OCTET
@@ -122,7 +125,7 @@ typedef enum {
 } tftp_error_t;
 
 typedef struct tftp_packet {
-  unsigned char data[516];
+  unsigned char data[2 + 2 + TFTP_BLOCKSIZE];
 } tftp_packet_t;
 
 typedef struct tftp_state_data {
@@ -274,7 +277,7 @@ static void tftp_send_first(tftp_state_data_t *state, tftp_event_t event)
       /* If we are uploading, send an WRQ */
       setpacketevent(&state->spacket, TFTP_EVENT_WRQ);
       filename = curl_easy_unescape(data, filename, 0, NULL);
-      state->conn->upload_fromhere = (char *)&state->spacket.data[2];
+      state->conn->upload_fromhere = (char *)&state->spacket.data[4];
       if(data->set.infilesize != -1)
         Curl_pgrsSetUploadSize(data, data->set.infilesize);
     }
@@ -283,7 +286,7 @@ static void tftp_send_first(tftp_state_data_t *state, tftp_event_t event)
       setpacketevent(&state->spacket, TFTP_EVENT_RRQ);
     }
     snprintf((char *)&state->spacket.data[2],
-             512,
+             TFTP_BLOCKSIZE,
              "%s%c%s%c", filename, '\0',  mode, '\0');
     sbytes = 4 + (int)strlen(filename) + (int)strlen(mode);
     sbytes = sendto(state->sockfd, (void *)&state->spacket,
@@ -291,7 +294,7 @@ static void tftp_send_first(tftp_state_data_t *state, tftp_event_t event)
                     state->conn->ip_addr->ai_addr,
                     state->conn->ip_addr->ai_addrlen);
     if(sbytes < 0) {
-      failf(data, "%s\n", strerror(errno));
+      failf(data, "%s\n", Curl_strerror(state->conn, errno));
     }
     break;
 
@@ -359,10 +362,10 @@ static void tftp_rx(tftp_state_data_t *state, tftp_event_t event)
                     (struct sockaddr *)&state->remote_addr,
                     state->remote_addrlen);
     if(sbytes < 0) {
-      failf(data, "%s\n", strerror(errno));
+      failf(data, "%s\n", Curl_strerror(state->conn, errno));
     }
 
-    /* Check if completed (That is, a less than full packet is recieved) */
+    /* Check if completed (That is, a less than full packet is received) */
     if (state->rbytes < (int)sizeof(state->spacket)){
       state->state = TFTP_STATE_FIN;
     }
@@ -387,7 +390,7 @@ static void tftp_rx(tftp_state_data_t *state, tftp_event_t event)
                       state->remote_addrlen);
       /* Check all sbytes were sent */
       if(sbytes<0) {
-        failf(data, "%s\n", strerror(errno));
+        failf(data, "%s\n", Curl_strerror(state->conn, errno));
       }
     }
     break;
@@ -401,7 +404,7 @@ static void tftp_rx(tftp_state_data_t *state, tftp_event_t event)
     break;
   }
   Curl_pgrsSetDownloadCounter(data,
-                              (curl_off_t) state->block*512);
+                              (curl_off_t) state->block*TFTP_BLOCKSIZE);
 }
 
 /**********************************************************
@@ -433,6 +436,16 @@ static void tftp_tx(tftp_state_data_t *state, tftp_event_t event)
         failf(data, "%s\n",
               "tftp_tx: giving up waiting for block %d ack",
               state->block);
+      } else {
+	/* Re-send the data packet */
+	sbytes = sendto(state->sockfd, (void *)&state->spacket,
+			4+state->sbytes, SEND_4TH_ARG,
+			(struct sockaddr *)&state->remote_addr,
+			state->remote_addrlen);
+	/* Check all sbytes were sent */
+	if(sbytes<0) {
+	  failf(data, "%s\n", Curl_strerror(state->conn, errno));
+	}
       }
       return;
     }
@@ -442,18 +455,18 @@ static void tftp_tx(tftp_state_data_t *state, tftp_event_t event)
     state->retries = 0;
     setpacketevent(&state->spacket, TFTP_EVENT_DATA);
     setpacketblock(&state->spacket, state->block);
-    if(state->block > 1 && state->sbytes < 512) {
+    if(state->block > 1 && state->sbytes < TFTP_BLOCKSIZE) {
       state->state = TFTP_STATE_FIN;
       return;
     }
-    Curl_fillreadbuffer(state->conn, 512, &state->sbytes);
+    Curl_fillreadbuffer(state->conn, TFTP_BLOCKSIZE, &state->sbytes);
     sbytes = sendto(state->sockfd, (void *)state->spacket.data,
                     4+state->sbytes, SEND_4TH_ARG,
                     (struct sockaddr *)&state->remote_addr,
                     state->remote_addrlen);
     /* Check all sbytes were sent */
     if(sbytes<0) {
-      failf(data, "%s\n", strerror(errno));
+      failf(data, "%s\n", Curl_strerror(state->conn, errno));
     }
     break;
 
@@ -474,7 +487,7 @@ static void tftp_tx(tftp_state_data_t *state, tftp_event_t event)
                       state->remote_addrlen);
       /* Check all sbytes were sent */
       if(sbytes<0) {
-        failf(data, "%s\n", strerror(errno));
+        failf(data, "%s\n", Curl_strerror(state->conn, errno));
       }
     }
     break;
@@ -489,7 +502,7 @@ static void tftp_tx(tftp_state_data_t *state, tftp_event_t event)
   }
 
   /* Update the progress meter */
-  Curl_pgrsSetUploadCounter(data, (curl_off_t) state->block*512);
+  Curl_pgrsSetUploadCounter(data, (curl_off_t) state->block*TFTP_BLOCKSIZE);
 }
 
 /**********************************************************
@@ -675,9 +688,12 @@ CURLcode Curl_tftp(struct connectdata *conn, bool *done)
 
 	switch(event) {
 	case TFTP_EVENT_DATA:
-	  if (state->rbytes > 4)
+	  /* Don't pass to the client empty or retransmitted packets */
+	  if (state->rbytes > 4 && 
+	      ((state->block+1) == getrpacketblock(&state->rpacket))) {
 	    Curl_client_write(data, CLIENTWRITE_BODY,
 			  (char *)&state->rpacket.data[4], state->rbytes-4);
+	  }
 	  break;
 	case TFTP_EVENT_ERROR:
 	  state->error = (tftp_error_t)getrpacketblock(&state->rpacket);