readme

FUZZING.md

@@ -0,0 +1,34 @@
+## Fuzzing
+
+Fuzzing is mainly applicable to packages that parse complex inputs (both text and binary), and is especially useful for hardening of systems that parse inputs from potentially malicious users (e.g. anything accepted over a network).
+To run a p2p protocol fuzzer locally, use the command:
+
+```
+make fuzz
+```
+That command should generate a `gossip-fuzz.zip` in the `fuzzing/` directory and runs fuzzer:
+
+```
+2020/12/30 22:50:51 workers: 0, corpus: 1 (3s ago), crashers: 0, restarts: 1/0, execs: 0 (0/sec), cover: 0, uptime: 3s
+2020/12/30 22:50:54 workers: 0, corpus: 1 (6s ago), crashers: 0, restarts: 1/0, execs: 0 (0/sec), cover: 0, uptime: 6s
+2020/12/30 22:50:57 workers: 3, corpus: 1 (9s ago), crashers: 0, restarts: 1/0, execs: 0 (0/sec), cover: 0, uptime: 9s
+2020/12/30 22:51:00 workers: 3, corpus: 1 (12s ago), crashers: 1, restarts: 1/0, execs: 0 (0/sec), cover: 0, uptime: 12s
+2020/12/30 22:51:03 workers: 3, corpus: 1 (15s ago), crashers: 1, restarts: 1/0, execs: 0 (0/sec), cover: 0, uptime: 15s
+2020/12/30 22:51:06 workers: 3, corpus: 1 (18s ago), crashers: 1, restarts: 1/0, execs: 0 (0/sec), cover: 0, uptime: 18s
+2020/12/30 22:51:09 workers: 3, corpus: 1 (21s ago), crashers: 1, restarts: 1/0, execs: 0 (0/sec), cover: 0, uptime: 21s
+2020/12/30 22:51:12 workers: 3, corpus: 1 (24s ago), crashers: 1, restarts: 1/0, execs: 0 (0/sec), cover: 0, uptime: 24s
+2020/12/30 22:51:15 workers: 3, corpus: 1 (27s ago), crashers: 1, restarts: 1/0, execs: 0 (0/sec), cover: 0, uptime: 27s
+2020/12/30 22:51:18 workers: 3, corpus: 1 (30s ago), crashers: 1, restarts: 1/0, execs: 0 (0/sec), cover: 0, uptime: 30s
+2020/12/30 22:51:21 workers: 3, corpus: 1 (33s ago), crashers: 1, restarts: 1/0, execs: 0 (0/sec), cover: 0, uptime: 33s
+2020/12/30 22:51:24 workers: 3, corpus: 1 (36s ago), crashers: 1, restarts: 1/0, execs: 0 (0/sec), cover: 0, uptime: 36s
+2020/12/30 22:51:27 workers: 3, corpus: 1 (39s ago), crashers: 1, restarts: 1/0, execs: 0 (0/sec), cover: 0, uptime: 39s
+2020/12/30 22:51:30 workers: 3, corpus: 1 (42s ago), crashers: 1, restarts: 1/0, execs: 0 (0/sec), cover: 0, uptime: 42s
+```
+
+See [github.com/dvyukov/go-fuzz](https://github.com/dvyukov/go-fuzz) to get more details.
+
+
+### Notes
+
+Once a 'crasher' is found, the fuzzer tries to avoid reporting the same vector twice, so stores the fault in the `suppressions` folder. Thus, if you 
+e.g. make changes to fix a bug, you should _remove_ all data from the `suppressions`-folder, to verify that the issue is indeed resolved. 

README.md

@@ -135,6 +135,9 @@ ok  	github.com/Fantom-foundation/go-opera/gossip/filters	1.250s
 ok  	github.com/Fantom-foundation/go-opera/integration	21.640s
 ```
 
+Also it is tested with [fuzzing](./FUZZING.md).
+
+
 ### Operating a private network (fakenet)
 
 Fakenet is a private network optimized for your private testing.

gossip/handler_fuzz.go

@@ -1,4 +1,4 @@
-//build gofuzz
+//+build gofuzz
 
 package gossip