Commit 98bac62c authored by Pavel Shilovsky's avatar Pavel Shilovsky Committed by Steve French

CIFS: Move RFC1002 check to a separate function

Reviewed-and-Tested-by: default avatarJeff Layton <jlayton@redhat.com>
Signed-off-by: default avatarPavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: default avatarSteve French <sfrench@us.ibm.com>
parent e7015fb1
...@@ -416,6 +416,63 @@ read_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg, ...@@ -416,6 +416,63 @@ read_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg,
return rc; return rc;
} }
static bool
check_rfc1002_header(struct TCP_Server_Info *server, char *buf)
{
char temp = *buf;
unsigned int pdu_length = be32_to_cpu(
((struct smb_hdr *)buf)->smb_buf_length);
/*
* The first byte big endian of the length field,
* is actually not part of the length but the type
* with the most common, zero, as regular data.
*/
if (temp == (char) RFC1002_SESSION_KEEP_ALIVE) {
return false;
} else if (temp == (char)RFC1002_POSITIVE_SESSION_RESPONSE) {
cFYI(1, "Good RFC 1002 session rsp");
return false;
} else if (temp == (char)RFC1002_NEGATIVE_SESSION_RESPONSE) {
/*
* We get this from Windows 98 instead of an error on
* SMB negprot response.
*/
cFYI(1, "Negative RFC1002 Session Response Error 0x%x)",
pdu_length);
/* give server a second to clean up */
msleep(1000);
/*
* Always try 445 first on reconnect since we get NACK
* on some if we ever connected to port 139 (the NACK
* is since we do not begin with RFC1001 session
* initialize frame).
*/
cifs_set_port((struct sockaddr *)
&server->dstaddr, CIFS_PORT);
cifs_reconnect(server);
wake_up(&server->response_q);
return false;
} else if (temp != (char) 0) {
cERROR(1, "Unknown RFC 1002 frame");
cifs_dump_mem(" Received Data: ", buf, 4);
cifs_reconnect(server);
return false;
}
/* else we have an SMB response */
if ((pdu_length > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) ||
(pdu_length < sizeof(struct smb_hdr) - 1 - 4)) {
cERROR(1, "Invalid size SMB length %d pdu_length %d",
4, pdu_length+4);
cifs_reconnect(server);
wake_up(&server->response_q);
return false;
}
return true;
}
static int static int
cifs_demultiplex_thread(void *p) cifs_demultiplex_thread(void *p)
{ {
...@@ -429,7 +486,6 @@ cifs_demultiplex_thread(void *p) ...@@ -429,7 +486,6 @@ cifs_demultiplex_thread(void *p)
struct list_head *tmp, *tmp2; struct list_head *tmp, *tmp2;
struct task_struct *task_to_wake = NULL; struct task_struct *task_to_wake = NULL;
struct mid_q_entry *mid_entry; struct mid_q_entry *mid_entry;
char temp;
bool isLargeBuf = false; bool isLargeBuf = false;
bool isMultiRsp; bool isMultiRsp;
int rc; int rc;
...@@ -482,59 +538,21 @@ cifs_demultiplex_thread(void *p) ...@@ -482,59 +538,21 @@ cifs_demultiplex_thread(void *p)
else if (rc == 1) else if (rc == 1)
continue; continue;
/* The right amount was read from socket - 4 bytes */ /*
/* so we can now interpret the length field */ * The right amount was read from socket - 4 bytes,
* so we can now interpret the length field.
/* the first byte big endian of the length field, */
is actually not part of the length but the type
with the most common, zero, as regular data */
temp = *buf;
/* Note that FC 1001 length is big endian on the wire, /*
but we convert it here so it is always manipulated * Note that RFC 1001 length is big endian on the wire,
as host byte order */ * but we convert it here so it is always manipulated
* as host byte order.
*/
pdu_length = be32_to_cpu(smb_buffer->smb_buf_length); pdu_length = be32_to_cpu(smb_buffer->smb_buf_length);
cFYI(1, "rfc1002 length 0x%x", pdu_length+4); cFYI(1, "rfc1002 length 0x%x", pdu_length+4);
if (!check_rfc1002_header(server, buf))
if (temp == (char) RFC1002_SESSION_KEEP_ALIVE) {
continue;
} else if (temp == (char)RFC1002_POSITIVE_SESSION_RESPONSE) {
cFYI(1, "Good RFC 1002 session rsp");
continue;
} else if (temp == (char)RFC1002_NEGATIVE_SESSION_RESPONSE) {
/* we get this from Windows 98 instead of
an error on SMB negprot response */
cFYI(1, "Negative RFC1002 Session Response Error 0x%x)",
pdu_length);
/* give server a second to clean up */
msleep(1000);
/* always try 445 first on reconnect since we get NACK
* on some if we ever connected to port 139 (the NACK
* is since we do not begin with RFC1001 session
* initialize frame)
*/
cifs_set_port((struct sockaddr *)
&server->dstaddr, CIFS_PORT);
cifs_reconnect(server);
wake_up(&server->response_q);
continue;
} else if (temp != (char) 0) {
cERROR(1, "Unknown RFC 1002 frame");
cifs_dump_mem(" Received Data: ", buf, length);
cifs_reconnect(server);
continue;
}
/* else we have an SMB response */
if ((pdu_length > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) ||
(pdu_length < sizeof(struct smb_hdr) - 1 - 4)) {
cERROR(1, "Invalid size SMB length %d pdu_length %d",
length, pdu_length+4);
cifs_reconnect(server);
wake_up(&server->response_q);
continue; continue;
}
/* else length ok */ /* else length ok */
if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE - 4) { if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE - 4) {
......
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