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s3:smb2_server: split out a smb2_validate_sequence_number() function

metze
This commit is contained in:
Stefan Metzmacher 2012-06-25 23:17:55 +02:00
parent d6e7a76461
commit 984fdaf914

View File

@ -293,13 +293,76 @@ static NTSTATUS smbd_smb2_request_create(struct smbd_server_connection *sconn,
return NT_STATUS_OK;
}
static bool smb2_validate_sequence_number(struct smbd_server_connection *sconn,
uint64_t message_id, uint64_t seq_id)
{
struct bitmap *credits_bm = sconn->smb2.credits_bitmap;
unsigned int offset;
if (seq_id < sconn->smb2.seqnum_low) {
DEBUG(0,("smb2_validate_sequence_number: bad message_id "
"%llu (sequence id %llu) (low = %llu, max = %lu)\n",
(unsigned long long)message_id,
(unsigned long long)seq_id,
(unsigned long long)sconn->smb2.seqnum_low,
(unsigned long)sconn->smb2.max_credits));
return false;
}
if (seq_id > (sconn->smb2.seqnum_low + sconn->smb2.max_credits)) {
DEBUG(0,("smb2_validate_sequence_number: bad message_id "
"%llu (sequence id %llu) (low = %llu, max = %lu)\n",
(unsigned long long)message_id,
(unsigned long long)seq_id,
(unsigned long long)sconn->smb2.seqnum_low,
(unsigned long)sconn->smb2.max_credits));
return false;
}
offset = seq_id % sconn->smb2.max_credits;
if (bitmap_query(credits_bm, offset)) {
DEBUG(0,("smb2_validate_sequence_number: duplicate message_id "
"%llu (sequence id %llu) (low = %llu, max = %lu) "
"(bm offset %u)\n",
(unsigned long long)message_id,
(unsigned long long)seq_id,
(unsigned long long)sconn->smb2.seqnum_low,
(unsigned long)sconn->smb2.max_credits,
offset));
return false;
}
/* Mark the message_ids as seen in the bitmap. */
bitmap_set(credits_bm, offset);
if (seq_id != sconn->smb2.seqnum_low) {
return true;
}
/*
* Move the window forward by all the message_id's
* already seen.
*/
while (bitmap_query(credits_bm, offset)) {
DEBUG(10,("smb2_validate_sequence_number: clearing "
"id %llu (position %u) from bitmap\n",
(unsigned long long)(sconn->smb2.seqnum_low),
offset));
bitmap_clear(credits_bm, offset);
sconn->smb2.seqnum_low += 1;
offset = sconn->smb2.seqnum_low % sconn->smb2.max_credits;
}
return true;
}
static bool smb2_validate_message_id(struct smbd_server_connection *sconn,
const uint8_t *inhdr)
{
uint64_t message_id = BVAL(inhdr, SMB2_HDR_MESSAGE_ID);
struct bitmap *credits_bm = sconn->smb2.credits_bitmap;
uint16_t opcode = IVAL(inhdr, SMB2_HDR_OPCODE);
unsigned int bitmap_offset;
uint16_t credit_charge = 1;
uint64_t i;
@ -308,17 +371,6 @@ static bool smb2_validate_message_id(struct smbd_server_connection *sconn,
return true;
}
if (message_id < sconn->smb2.seqnum_low ||
message_id > (sconn->smb2.seqnum_low +
(sconn->smb2.max_credits))) {
DEBUG(0,("smb2_validate_message_id: bad message_id "
"%llu (low = %llu, max = %lu)\n",
(unsigned long long)message_id,
(unsigned long long)sconn->smb2.seqnum_low,
(unsigned long)sconn->smb2.max_credits ));
return false;
}
if (sconn->smb2.credits_granted == 0) {
DEBUG(0,("smb2_validate_message_id: client used more "
"credits than granted, message_id (%llu)\n",
@ -339,9 +391,6 @@ static bool smb2_validate_message_id(struct smbd_server_connection *sconn,
(unsigned long long) sconn->smb2.max_credits,
(unsigned long long) sconn->smb2.seqnum_low));
/* substract used credits */
sconn->smb2.credits_granted -= credit_charge;
/*
* now check the message ids
*
@ -350,36 +399,24 @@ static bool smb2_validate_message_id(struct smbd_server_connection *sconn,
* e.g. current mid = 15, charge 5 => mark 15-19 as used
*/
for (i = message_id; i <= (message_id+credit_charge-1); i++) {
for (i = 0; i <= (credit_charge-1); i++) {
uint64_t id = message_id + i;
bool ok;
DEBUG(11, ("Iterating mid %llu\n", (unsigned long long) i));
DEBUG(11, ("Iterating mid %llu charge %u (sequence %llu)\n",
(unsigned long long)message_id,
credit_charge,
(unsigned long long)id));
/* Mark the message_ids as seen in the bitmap. */
bitmap_offset = i % sconn->smb2.max_credits;
if (bitmap_query(credits_bm, bitmap_offset)) {
DEBUG(0,("smb2_validate_message_id: duplicate "
"message_id %llu (bm offset %u)\n",
(unsigned long long)i, bitmap_offset));
ok = smb2_validate_sequence_number(sconn, message_id, id);
if (!ok) {
return false;
}
bitmap_set(credits_bm, bitmap_offset);
if (i == sconn->smb2.seqnum_low) {
/* Move the window forward by all the message_id's
already seen. */
while (bitmap_query(credits_bm, bitmap_offset)) {
DEBUG(10,("smb2_validate_message_id: clearing "
"id %llu (position %u) from bitmap\n",
(unsigned long long)(sconn->smb2.seqnum_low),
bitmap_offset));
bitmap_clear(credits_bm, bitmap_offset);
sconn->smb2.seqnum_low += 1;
bitmap_offset = sconn->smb2.seqnum_low %
sconn->smb2.max_credits;
}
}
}
/* substract used credits */
sconn->smb2.credits_granted -= credit_charge;
return true;
}