github.com/decred/dcrlnd@v0.7.6/fuzz/brontide/random_actthree.go (about)

     1  //go:build gofuzz
     2  // +build gofuzz
     3  
     4  package brontidefuzz
     5  
     6  import (
     7  	"github.com/decred/dcrlnd/brontide"
     8  )
     9  
    10  // Fuzz_random_actthree is a go-fuzz harness for ActThree in the brontide
    11  // handshake.
    12  func Fuzz_random_actthree(data []byte) int {
    13  	// Check if data is large enough.
    14  	if len(data) < brontide.ActThreeSize {
    15  		return 1
    16  	}
    17  
    18  	// This will return brontide machines with random keys.
    19  	initiator, responder := getBrontideMachines()
    20  
    21  	// Generate ActOne and send to the responder.
    22  	actOne, err := initiator.GenActOne()
    23  	if err != nil {
    24  		nilAndPanic(initiator, responder, err)
    25  	}
    26  
    27  	// Receiving ActOne should succeed, so we panic on error.
    28  	if err := responder.RecvActOne(actOne); err != nil {
    29  		nilAndPanic(initiator, responder, err)
    30  	}
    31  
    32  	// Generate ActTwo - this is not sent to the initiator because nothing is
    33  	// done with the initiator after this point and it would slow down fuzzing.
    34  	// GenActTwo needs to be called to set the appropriate state in the
    35  	// responder machine.
    36  	_, err = responder.GenActTwo()
    37  	if err != nil {
    38  		nilAndPanic(initiator, responder, err)
    39  	}
    40  
    41  	// Copy data into [ActThreeSize]byte.
    42  	var actThree [brontide.ActThreeSize]byte
    43  	copy(actThree[:], data)
    44  
    45  	// Responder receives ActThree, should fail on the MAC check.
    46  	if err := responder.RecvActThree(actThree); err == nil {
    47  		nilAndPanic(initiator, responder, nil)
    48  	}
    49  
    50  	return 1
    51  }