From: Joseph C. Lehner <joseph.c.lehner@gmail.com>
Date: Thu, 2 May 2019 10:18:22 +0000 (+0200)
Subject: Conditionally enable TFTP block rollover hack
X-Git-Tag: v0.9.14~17
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=b3ba1c016b8fb2c970da9aae3fcb48fb4c255c94;p=oweals%2Fnmrpflash.git

Conditionally enable TFTP block rollover hack
---

diff --git a/tftp.c b/tftp.c
index f81f877..1e0dd73 100644
--- a/tftp.c
+++ b/tftp.c
@@ -314,6 +314,7 @@ int tftp_put(struct nmrpd_args *args)
 	char rx[2048], tx[2048];
 	const char *file_remote = args->file_remote;
 	char *val, *end;
+	bool freeze_block = false;
 
 	sock = -1;
 	ret = -1;
@@ -400,7 +401,7 @@ int tftp_put(struct nmrpd_args *args)
 
 		if (timeouts || ackblock == block) {
 			if (!timeouts) {
-				if (block < UINT16_MAX) {
+				if (!freeze_block) {
 					++block;
 				}
 
@@ -432,9 +433,20 @@ int tftp_put(struct nmrpd_args *args)
 			}
 
 			if (ackblock != -1 && ++errors > 5) {
-				fprintf(stderr, "Protocol error; bailing out.\n");
-				ret = -1;
-				goto cleanup;
+				if (ackblock == UINT16_MAX && block == 0 && !freeze_block) {
+					/* work around the 32 MiB limit if block rollover is not
+					 * supported, by transmitting all remaining packets as
+					 * block #65535 - reported working on a Netgear D7000.
+					 */
+					block = UINT16_MAX;
+					freeze_block = true;
+					errors = 0;
+					printf("Transmitting rest of file as block %d.\n", block);
+				} else {
+					fprintf(stderr, "Protocol error; bailing out.\n");
+					ret = -1;
+					goto cleanup;
+				}
 			}
 		}