admin/libiscsi
1
0
Fork 0
Code Issues Pull Requests Actions 2 Packages Projects Releases Wiki Activity

socket: calculate header checksum at the right place

Browse Source 
we mangled the PDU header after calculating the checksum which
effectively broke CRC32C header digests completely.

Signed-off-by: Peter Lieven <pl@kamp.de>
This commit is contained in:
Peter Lieven
2017-01-05 12:28:37 +01:00
parent ed1ed27dde
commit 23738bf1c3
1 changed files with 26 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files

44
lib/socket.c
View File

@@ -675,6 +675,25 @@ iscsi_read_from_socket(struct iscsi_context *iscsi)
return 0;
}
static int iscsi_pdu_update_headerdigest(struct iscsi_context *iscsi, struct iscsi_pdu *pdu)
{
unsigned long crc;
if (pdu->outdata.size < ISCSI_RAW_HEADER_SIZE + ISCSI_DIGEST_SIZE) {
iscsi_set_error(iscsi, "PDU too small (%u) to contain header digest",
(unsigned int) pdu->outdata.size);
return -1;
}
crc = crc32c((char *)pdu->outdata.data, ISCSI_RAW_HEADER_SIZE);
pdu->outdata.data[ISCSI_RAW_HEADER_SIZE+3] = (crc >> 24)&0xff;
pdu->outdata.data[ISCSI_RAW_HEADER_SIZE+2] = (crc >> 16)&0xff;
pdu->outdata.data[ISCSI_RAW_HEADER_SIZE+1] = (crc >> 8)&0xff;
pdu->outdata.data[ISCSI_RAW_HEADER_SIZE+0] = (crc) &0xff;
return 0;
}
static int
iscsi_write_to_socket(struct iscsi_context *iscsi)
{
@@ -724,7 +743,13 @@ iscsi_write_to_socket(struct iscsi_context *iscsi)
/* set exp statsn */
iscsi_pdu_set_expstatsn(iscsi->outqueue_current, iscsi->statsn + 1);
/* calculate header checksum */
if (iscsi->header_digest != ISCSI_HEADER_DIGEST_NONE &&
iscsi_pdu_update_headerdigest(iscsi, iscsi->outqueue_current) != 0) {
return -1;
}
ISCSI_LIST_REMOVE(&iscsi->outqueue, iscsi->outqueue_current);
if (!(iscsi->outqueue_current->flags & ISCSI_PDU_DELETE_WHEN_SENT)) {
/* we have to add the pdu to the waitqueue already here
@@ -954,23 +979,6 @@ static int iscsi_tcp_queue_pdu(struct iscsi_context *iscsi,
return -1;
}
if (iscsi->header_digest != ISCSI_HEADER_DIGEST_NONE) {
unsigned long crc;
if (pdu->outdata.size < ISCSI_RAW_HEADER_SIZE + 4) {
iscsi_set_error(iscsi, "PDU too small (%u) to contain header digest",
(unsigned int) pdu->outdata.size);
return -1;
}
crc = crc32c((char *)pdu->outdata.data, ISCSI_RAW_HEADER_SIZE);
pdu->outdata.data[ISCSI_RAW_HEADER_SIZE+3] = (crc >> 24)&0xff;
pdu->outdata.data[ISCSI_RAW_HEADER_SIZE+2] = (crc >> 16)&0xff;
pdu->outdata.data[ISCSI_RAW_HEADER_SIZE+1] = (crc >> 8)&0xff;
pdu->outdata.data[ISCSI_RAW_HEADER_SIZE+0] = (crc) &0xff;
}
iscsi_add_to_outqueue(iscsi, pdu);
return 0;