BNF Fuzzer

Generate random messages based on their BNF definition.

Quickl Start

Generate 10 random postal addresses:

$ go build .
$ ./bnfuzzer -file ./examples/postal.bnf -entry postal-address -count 10

Syntax of BNF files

We are trying to support BNF and ABNF syntaxes simultenously, by allowing to use different syntactical elements for the same constructions. For example you can use / and | for Rule Alternatives and even mix them up in the same file. Both of them are interpreted as aliternatives.

Maybe with some limitations we can enable support for EBNF as well, but it's a bit difficult because EBNF uses ; to indicate the end of the rule definition, but ABNF and BNF use it for comments.

The descriptions below are stolen from wikipedia.

Comments

; comment

For some reason I also added C-style comments. Maybe I should remove them so to not create even more confusion between BNF dialects...

// comment

Concatenation

fu = %x61 ; a
bar = %x62 ; b
mumble = fu bar fu

Alternative

fubar = fu / bar

or

fubar = fu | bar

Incremental alternatives

The rule

ruleset = alt1 / alt2
ruleset =/ alt3
ruleset =/ alt4 / alt5

is equivalent to

ruleset = alt1 / alt2 / alt3 / alt4 / alt5

Maybe to maintain the consistency with supporting mixed up syntax, we should allow to use =| along with =/...

Value range

OCTAL = %x30-37

is equivalent to

OCTAL = "0" / "1" / "2" / "3" / "4" / "5" / "6" / "7"

and also can be written as

OCTAL = "0" ... "9"

or

OCTAL = "\x30" ... "\x37"

Sequence group

group = a (b / c) d

Variable repetition

n*nRule

Specific repetition

nRule

Optional sequence

[Rule]