/**
* Test whether GUID is that of GTKG, and extract version major/minor, along
* with release status provided the `majp', `minp' and `relp' are non-NULL.
*/
static bool
guid_oob_is_gtkg(const guid_t *guid, uint8 *majp, uint8 *minp, bool *relp)
{
uint8 hec;
if (!guid_extract_gtkg_info(guid, 4, majp, minp, relp))
return FALSE; /* Marking incorrect, no need to compute HEC */
/*
* The HEC for OOB queries was made of the first 15 bytes for versions
* up to 0.98.4u (legacy encoding). Starting with 0.98.4, we have a
* different way of encoding the HEC to preserve its integrity even in
* the advent of OOB-proxying.
*
* Also bit 0 of the HEC is not significant (used to mark requeries)
* therefore it is masked out for comparison purposes.
*/
hec = peek_u8(&guid->v[15]) & ~GUID_REQUERY;
if (*majp >0 || *minp >= 99)
return booleanize((guid_hec_oob(guid) & ~GUID_REQUERY) == hec);
/*
* Transition period for servents earlier than 0.99: try the legacy marking
* for 0.97 and earlier. For 0.98, try the legacy marking first, then the
* new marking.
*/
if (*minp <= 97)
return booleanize((guid_hec_oob_legacy(guid) & ~GUID_REQUERY) == hec);
return booleanize((guid_hec_oob_legacy(guid) & ~GUID_REQUERY) == hec) ||
booleanize((guid_hec_oob(guid) & ~GUID_REQUERY) == hec);
}
/**
* Flag a MUID for OOB queries as being from GTKG, by patching `guid' in place.
*
* Bytes 4/5 become the GTKG version mark.
* Byte 15 becomes the HEC of the leading 15 bytes.
*/
static void
guid_flag_oob_gtkg(struct guid *muid)
{
poke_be16(&muid->v[4], gtkg_version_mark);
muid->v[15] = guid_hec_oob(muid); /* guid_hec() skips leading byte */
}
