Suricata

I'm unable to understand the statement, "direct 'sets' of Signature::alproto from keyword registration", could you please make it clearer?

With direct 'sets' I mean code like:

static int DetectHttpUriSetupSticky(DetectEngineCtx *de_ctx, Signature *s, const char *str)
{
    DetectBufferSetActiveList(s, g_http_uri_buffer_id);
    s->alproto = ALPROTO_HTTP;
    return 0;
}

Where Signature::alproto is set explicitly.

These cases should be replaced by calls to DetectSignatureSetAppProto. E.g.:

static int DetectHttpMethodSetupSticky(DetectEngineCtx *de_ctx, Signature *s, const char *str)
{
    if (DetectBufferSetActiveList(s, g_http_method_buffer_id) < 0)
        return -1;

    if (DetectSignatureSetAppProto(s, ALPROTO_HTTP) < 0)
        return -1;

    return 0;
}