On Fri, 13 Jul 2012 11:53:28 +0400
Pavel Shilovsky <pshilovsky@xxxxxxxxx> wrote:
> From: Pavel Shilovsky <piastry@xxxxxxxxxxx>
>
> and add negotiate request type to let set_credits know that
> we are only on negotiate stage and no need to make a decision
> about disabling echos and oplocks.
>
> Signed-off-by: Pavel Shilovsky <piastry@xxxxxxxxxxx>
> ---
> fs/cifs/Makefile | 3 +-
> fs/cifs/cifsglob.h | 13 ++-
> fs/cifs/cifssmb.c | 7 -
> fs/cifs/smb2misc.c | 7 +-
> fs/cifs/smb2ops.c | 22 ++++-
> fs/cifs/smb2pdu.c | 330 +++++++++++++++++++++++++++++++++++++++++++++++++++
> fs/cifs/smb2pdu.h | 39 ++++++
> fs/cifs/smb2proto.h | 7 +
> 8 files changed, 417 insertions(+), 11 deletions(-)
> create mode 100644 fs/cifs/smb2pdu.c
>
> diff --git a/fs/cifs/Makefile b/fs/cifs/Makefile
> index b77e9ec..daf6837 100644
> --- a/fs/cifs/Makefile
> +++ b/fs/cifs/Makefile
> @@ -16,4 +16,5 @@ cifs-$(CONFIG_CIFS_DFS_UPCALL) += dns_resolve.o cifs_dfs_ref.o
>
> cifs-$(CONFIG_CIFS_FSCACHE) += fscache.o cache.o
>
> -cifs-$(CONFIG_CIFS_SMB2) += smb2ops.o smb2maperror.o smb2transport.o smb2misc.o
> +cifs-$(CONFIG_CIFS_SMB2) += smb2ops.o smb2maperror.o smb2transport.o \
> + smb2misc.o smb2pdu.o
> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
> index 480b638..2d48f88 100644
> --- a/fs/cifs/cifsglob.h
> +++ b/fs/cifs/cifsglob.h
> @@ -313,6 +313,12 @@ get_rfc1002_length(void *buf)
> return be32_to_cpu(*((__be32 *)buf));
> }
>
> +static inline void
> +inc_rfc1001_len(void *buf, int count)
> +{
> + be32_add_cpu((__be32 *)buf, count);
> +}
> +
> struct TCP_Server_Info {
> struct list_head tcp_ses_list;
> struct list_head smb_ses_list;
> @@ -393,6 +399,10 @@ struct TCP_Server_Info {
> atomic_t in_send; /* requests trying to send */
> atomic_t num_waiters; /* blocked waiting to get in sendrecv */
> #endif
> +#ifdef CONFIG_CIFS_SMB2
> + unsigned int max_read;
> + unsigned int max_write;
> +#endif /* CONFIG_CIFS_SMB2 */
> };
>
> static inline unsigned int
> @@ -986,7 +996,8 @@ static inline void free_dfs_info_array(struct dfs_info3_param *param,
> /* Type of request operation */
> #define CIFS_ECHO_OP 0x080 /* echo request */
> #define CIFS_OBREAK_OP 0x0100 /* oplock break request */
> -#define CIFS_OP_MASK 0x0180 /* mask request type */
> +#define CIFS_NEG_OP 0x0200 /* negotiate request */
> +#define CIFS_OP_MASK 0x0380 /* mask request type */
>
> /* Security Flags: indicate type of session setup needed */
> #define CIFSSEC_MAY_SIGN 0x00001
> diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
> index 28b5116..409f5b0 100644
> --- a/fs/cifs/cifssmb.c
> +++ b/fs/cifs/cifssmb.c
> @@ -388,13 +388,6 @@ vt2_err:
> return -EINVAL;
> }
>
> -static inline void inc_rfc1001_len(void *pSMB, int count)
> -{
> - struct smb_hdr *hdr = (struct smb_hdr *)pSMB;
> -
> - be32_add_cpu(&hdr->smb_buf_length, count);
> -}
> -
> int
> CIFSSMBNegotiate(const unsigned int xid, struct cifs_ses *ses)
> {
> diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
> index d422678..e4dede4 100644
> --- a/fs/cifs/smb2misc.c
> +++ b/fs/cifs/smb2misc.c
> @@ -199,7 +199,7 @@ static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
> * Returns the pointer to the beginning of the data area. Length of the data
> * area and the offset to it (from the beginning of the smb are also returned.
> */
> -static char *
> +char *
> smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr)
> {
> *off = 0;
> @@ -218,6 +218,11 @@ smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr)
> */
> switch (hdr->Command) {
> case SMB2_NEGOTIATE:
> + *off = le16_to_cpu(
> + ((struct smb2_negotiate_rsp *)hdr)->SecurityBufferOffset);
> + *len = le16_to_cpu(
> + ((struct smb2_negotiate_rsp *)hdr)->SecurityBufferLength);
> + break;
> case SMB2_SESSION_SETUP:
> case SMB2_CREATE:
> case SMB2_READ:
> diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
> index c6f8154..2b5232b 100644
> --- a/fs/cifs/smb2ops.c
> +++ b/fs/cifs/smb2ops.c
> @@ -61,7 +61,7 @@ smb2_add_credits(struct TCP_Server_Info *server, const unsigned int add,
> val = server->ops->get_credits_field(server, optype);
> *val += add;
> server->in_flight--;
> - if (server->in_flight == 0)
> + if (server->in_flight == 0 && (optype & CIFS_OP_MASK) != CIFS_NEG_OP)
> rc = change_conf(server);
> spin_unlock(&server->req_lock);
> wake_up(&server->request_q);
> @@ -139,6 +139,24 @@ smb2_dump_detail(void *buf)
> #endif
> }
>
> +static bool
> +smb2_need_neg(struct TCP_Server_Info *server)
> +{
> + return server->max_read == 0;
> +}
> +
> +static int
> +smb2_negotiate(const unsigned int xid, struct cifs_ses *ses)
> +{
> + int rc;
> + ses->server->CurrentMid = 0;
> + rc = SMB2_negotiate(xid, ses);
> + /* BB we probably don't need to retry with modern servers */
> + if (rc == -EAGAIN)
> + rc = -EHOSTDOWN;
> + return rc;
> +}
> +
> struct smb_version_operations smb21_operations = {
> .setup_request = smb2_setup_request,
> .check_receive = smb2_check_receive,
> @@ -150,6 +168,8 @@ struct smb_version_operations smb21_operations = {
> .find_mid = smb2_find_mid,
> .check_message = smb2_check_message,
> .dump_detail = smb2_dump_detail,
> + .need_neg = smb2_need_neg,
> + .negotiate = smb2_negotiate,
> };
>
> struct smb_version_values smb21_values = {
> diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
> new file mode 100644
> index 0000000..719e4c4
> --- /dev/null
> +++ b/fs/cifs/smb2pdu.c
> @@ -0,0 +1,330 @@
> +/*
> + * fs/cifs/smb2pdu.c
> + *
> + * Copyright (C) International Business Machines Corp., 2009, 2011
> + * Etersoft, 2012
> + * Author(s): Steve French (sfrench@xxxxxxxxxx)
> + * Pavel Shilovsky (pshilovsky@xxxxxxxxx) 2012
> + *
> + * Contains the routines for constructing the SMB2 PDUs themselves
> + *
> + * This library is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU Lesser General Public License as published
> + * by the Free Software Foundation; either version 2.1 of the License, or
> + * (at your option) any later version.
> + *
> + * This library is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
> + * the GNU Lesser General Public License for more details.
> + *
> + * You should have received a copy of the GNU Lesser General Public License
> + * along with this library; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
> + */
> +
> + /* SMB2 PDU handling routines here - except for leftovers (eg session setup) */
> + /* Note that there are handle based routines which must be */
> + /* treated slightly differently for reconnection purposes since we never */
> + /* want to reuse a stale file handle and only the caller knows the file info */
> +
> +#include <linux/fs.h>
> +#include <linux/kernel.h>
> +#include <linux/vfs.h>
> +#include <linux/uaccess.h>
> +#include <linux/xattr.h>
> +#include "smb2pdu.h"
> +#include "cifsglob.h"
> +#include "cifsacl.h"
> +#include "cifsproto.h"
> +#include "smb2proto.h"
> +#include "cifs_unicode.h"
> +#include "cifs_debug.h"
> +#include "ntlmssp.h"
> +#include "smb2status.h"
> +
> +/*
> + * The following table defines the expected "StructureSize" of SMB2 requests
> + * in order by SMB2 command. This is similar to "wct" in SMB/CIFS requests.
> + *
> + * Note that commands are defined in smb2pdu.h in le16 but the array below is
> + * indexed by command in host byte order.
> + */
> +static const int smb2_req_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
> + /* SMB2_NEGOTIATE */ 36,
> + /* SMB2_SESSION_SETUP */ 25,
> + /* SMB2_LOGOFF */ 4,
> + /* SMB2_TREE_CONNECT */ 9,
> + /* SMB2_TREE_DISCONNECT */ 4,
> + /* SMB2_CREATE */ 57,
> + /* SMB2_CLOSE */ 24,
> + /* SMB2_FLUSH */ 24,
> + /* SMB2_READ */ 49,
> + /* SMB2_WRITE */ 49,
> + /* SMB2_LOCK */ 48,
> + /* SMB2_IOCTL */ 57,
> + /* SMB2_CANCEL */ 4,
> + /* SMB2_ECHO */ 4,
> + /* SMB2_QUERY_DIRECTORY */ 33,
> + /* SMB2_CHANGE_NOTIFY */ 32,
> + /* SMB2_QUERY_INFO */ 41,
> + /* SMB2_SET_INFO */ 33,
> + /* SMB2_OPLOCK_BREAK */ 24 /* BB this is 36 for LEASE_BREAK variant */
> +};
> +
> +
> +static void
> +smb2_hdr_assemble(struct smb2_hdr *hdr, __le16 smb2_cmd /* command */ ,
> + const struct cifs_tcon *tcon)
> +{
> + struct smb2_pdu *pdu = (struct smb2_pdu *)hdr;
> + char *temp = (char *)hdr;
> + /* lookup word count ie StructureSize from table */
> + __u16 parmsize = smb2_req_struct_sizes[le16_to_cpu(smb2_cmd)];
> +
> + /*
> + * smaller than SMALL_BUFFER_SIZE but bigger than fixed area of
> + * largest operations (Create)
> + */
> + memset(temp, 0, 256);
> +
> + /* Note this is only network field converted to big endian */
> + hdr->smb2_buf_length = cpu_to_be32(parmsize + sizeof(struct smb2_hdr)
> + - 4 /* RFC 1001 length field itself not counted */);
> +
> + hdr->ProtocolId[0] = 0xFE;
> + hdr->ProtocolId[1] = 'S';
> + hdr->ProtocolId[2] = 'M';
> + hdr->ProtocolId[3] = 'B';
> + hdr->StructureSize = cpu_to_le16(64);
> + hdr->Command = smb2_cmd;
> + hdr->CreditRequest = cpu_to_le16(2); /* BB make this dynamic */
> + hdr->ProcessId = cpu_to_le32((__u16)current->tgid);
> +
> + if (!tcon)
> + goto out;
> +
> + hdr->TreeId = tcon->tid;
> + /* Uid is not converted */
> + if (tcon->ses)
> + hdr->SessionId = tcon->ses->Suid;
> + /* BB check following DFS flags BB */
> + /* BB do we have to add check for SHI1005_FLAGS_DFS_ROOT too? */
> + /* if (tcon->share_flags & SHI1005_FLAGS_DFS)
> + hdr->Flags |= SMB2_FLAGS_DFS_OPERATIONS; */
> + /* BB how does SMB2 do case sensitive? */
> + /* if (tcon->nocase)
> + hdr->Flags |= SMBFLG_CASELESS; */
> + /* if (tcon->ses && tcon->ses->server &&
> + (tcon->ses->server->sec_mode & SECMODE_SIGN_REQUIRED))
> + hdr->Flags |= SMB2_FLAGS_SIGNED; */
Beware the crazy adjacent comments like this. That sort of thing been
the source of many difficult to find bugs in the past. Consider
cleaning this up and surrounding it with #if 0 or something?
I'd prefer to see the above removed and a nicely-formatted comment in
english take its place.
> +out:
> + pdu->StructureSize2 = cpu_to_le16(parmsize);
> + return;
> +}
> +
> +static int
> +smb2_reconnect(__le16 smb2_command, struct cifs_tcon *tcon)
> +{
> + int rc = 0;
> + /* BB add missing code here */
> + return rc;
> +}
> +
> +/*
> + * Allocate and return pointer to an SMB request hdr, and set basic
> + * SMB information in the SMB header. If the return code is zero, this
> + * function must have filled in request_buf pointer.
> + */
> +static int
> +small_smb2_init(__le16 smb2_command, struct cifs_tcon *tcon,
> + void **request_buf)
> +{
> + int rc = 0;
> +
> + rc = smb2_reconnect(smb2_command, tcon);
> + if (rc)
> + return rc;
> +
> + /* BB eventually switch this to SMB2 specific small buf size */
> + *request_buf = cifs_small_buf_get();
> + if (*request_buf == NULL) {
> + /* BB should we add a retry in here if not a writepage? */
> + return -ENOMEM;
> + }
> +
> + smb2_hdr_assemble((struct smb2_hdr *) *request_buf, smb2_command, tcon);
> +
> + if (tcon != NULL) {
> +#ifdef CONFIG_CIFS_STATS2
> + /*
> + uint16_t com_code = le16_to_cpu(smb2_command);
> + cifs_stats_inc(&tcon->stats.smb2_stats.smb2_com_sent[com_code]);
> + */
> +#endif
> + cifs_stats_inc(&tcon->num_smbs_sent);
> + }
> +
> + return rc;
> +}
> +
> +static void
> +free_rsp_buf(int resp_buftype, void *rsp)
> +{
> + if (resp_buftype == CIFS_SMALL_BUFFER)
> + cifs_small_buf_release(rsp);
> + else if (resp_buftype == CIFS_LARGE_BUFFER)
> + cifs_buf_release(rsp);
> +}
> +
> +#define SMB2_NUM_PROT 1
> +
> +#define SMB2_PROT 0
> +#define SMB21_PROT 1
> +#define BAD_PROT 0xFFFF
> +
> +#define SMB2_PROT_ID 0x0202
> +#define SMB21_PROT_ID 0x0210
> +#define BAD_PROT_ID 0xFFFF
> +
> +static struct {
> + int index;
> + __le16 name;
> +} smb2protocols[] = {
> + {SMB2_PROT, cpu_to_le16(SMB2_PROT_ID)},
> + {SMB21_PROT, cpu_to_le16(SMB21_PROT_ID)},
> + {BAD_PROT, cpu_to_le16(BAD_PROT_ID)}
> +};
> +
> +/*
> + *
> + * SMB2 Worker functions follow:
> + *
> + * The general structure of the worker functions is:
> + * 1) Call smb2_init (assembles SMB2 header)
> + * 2) Initialize SMB2 command specific fields in fixed length area of SMB
> + * 3) Call smb_sendrcv2 (sends request on socket and waits for response)
> + * 4) Decode SMB2 command specific fields in the fixed length area
> + * 5) Decode variable length data area (if any for this SMB2 command type)
> + * 6) Call free smb buffer
> + * 7) return
> + *
> + */
> +
> +int
> +SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
> +{
> + struct smb2_negotiate_req *req;
> + struct smb2_negotiate_rsp *rsp;
> + struct kvec iov[1];
> + int rc = 0;
> + int resp_buftype;
> + struct TCP_Server_Info *server;
> + unsigned int sec_flags;
> + u16 i;
> + u16 temp = 0;
> + int blob_offset, blob_length;
> + char *security_blob;
> + int flags = CIFS_NEG_OP;
> +
> + cFYI(1, "Negotiate protocol");
> +
> + if (ses->server)
> + server = ses->server;
> + else {
> + rc = -EIO;
> + return rc;
> + }
> +
> + rc = small_smb2_init(SMB2_NEGOTIATE, NULL, (void **) &req);
> + if (rc)
> + return rc;
> +
> + /* if any of auth flags (ie not sign or seal) are overriden use them */
> + if (ses->overrideSecFlg & (~(CIFSSEC_MUST_SIGN | CIFSSEC_MUST_SEAL)))
> + sec_flags = ses->overrideSecFlg; /* BB FIXME fix sign flags?*/
> + else /* if override flags set only sign/seal OR them with global auth */
> + sec_flags = global_secflags | ses->overrideSecFlg;
> +
> + cFYI(1, "sec_flags 0x%x", sec_flags);
> +
> + req->hdr.SessionId = 0;
> +
> + for (i = 0; i < SMB2_NUM_PROT; i++)
> + req->Dialects[i] = smb2protocols[i].name;
> +
> + req->DialectCount = cpu_to_le16(i);
> + inc_rfc1001_len(req, i * 2);
> +
> + /* only one of SMB2 signing flags may be set in SMB2 request */
> + if ((sec_flags & CIFSSEC_MUST_SIGN) == CIFSSEC_MUST_SIGN)
> + temp = SMB2_NEGOTIATE_SIGNING_REQUIRED;
> + else if (sec_flags & CIFSSEC_MAY_SIGN) /* MAY_SIGN is a single flag */
> + temp = SMB2_NEGOTIATE_SIGNING_ENABLED;
> +
Why "temp" here? A better variable name would be nice.
> + req->SecurityMode = cpu_to_le16(temp);
> +
> + req->Capabilities = cpu_to_le32(SMB2_GLOBAL_CAP_DFS);
> +
> + iov[0].iov_base = (char *)req;
> + /* 4 for rfc1002 length field */
> + iov[0].iov_len = get_rfc1002_length(req) + 4;
> +
> + rc = SendReceive2(xid, ses, iov, 1, &resp_buftype, flags);
> +
> + rsp = (struct smb2_negotiate_rsp *)iov[0].iov_base;
> + /*
> + * No tcon so can't do
> + * cifs_stats_inc(&tcon->stats.smb2_stats.smb2_com_fail[SMB2...]);
> + */
> + if (rc != 0)
> + goto neg_exit;
> +
> + if (rsp == NULL) {
> + rc = -EIO;
> + goto neg_exit;
> + }
> +
> + cFYI(1, "mode 0x%x", rsp->SecurityMode);
> +
> + if (rsp->DialectRevision == smb2protocols[SMB21_PROT].name)
> + cFYI(1, "negotiated smb2.1 dialect");
> + else if (rsp->DialectRevision == smb2protocols[SMB2_PROT].name)
> + cFYI(1, "negotiated smb2 dialect");
> + else {
> + cERROR(1, "Illegal dialect returned by server %d",
> + le16_to_cpu(rsp->DialectRevision));
> + rc = -EIO;
> + goto neg_exit;
> + }
> + server->dialect = le16_to_cpu(rsp->DialectRevision);
> +
> + server->maxBuf = le32_to_cpu(rsp->MaxTransactSize);
> + server->max_read = le32_to_cpu(rsp->MaxReadSize);
> + server->max_write = le32_to_cpu(rsp->MaxWriteSize);
> + /* BB Do we need to validate the SecurityMode? */
> + server->sec_mode = le16_to_cpu(rsp->SecurityMode);
> + server->capabilities = le32_to_cpu(rsp->Capabilities);
> +
> + security_blob = smb2_get_data_area_len(&blob_offset, &blob_length,
> + &rsp->hdr);
> + if (blob_length == 0) {
> + cERROR(1, "missing security blob on negprot");
> + rc = -EIO;
> + goto neg_exit;
> + }
> +#ifdef CONFIG_SMB2_ASN1 /* BB REMOVEME when updated asn1.c ready */
> + rc = decode_neg_token_init(security_blob, blob_length,
> + &server->sec_type);
> + if (rc == 1)
> + rc = 0;
> + else if (rc == 0) {
> + rc = -EIO;
> + goto neg_exit;
> + }
> +#endif
> +
> +neg_exit:
> + free_rsp_buf(resp_buftype, rsp);
> + return rc;
> +}
> diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
> index b08a277..ef8dae2 100644
> --- a/fs/cifs/smb2pdu.h
> +++ b/fs/cifs/smb2pdu.h
> @@ -148,4 +148,43 @@ struct smb2_err_rsp {
> __u8 ErrorData[1]; /* variable length */
> } __packed;
>
> +struct smb2_negotiate_req {
> + struct smb2_hdr hdr;
> + __le16 StructureSize; /* Must be 36 */
> + __le16 DialectCount;
> + __le16 SecurityMode;
> + __le16 Reserved; /* MBZ */
> + __le32 Capabilities;
> + __u8 ClientGUID[16]; /* MBZ */
> + __le64 ClientStartTime; /* MBZ */
> + __le16 Dialects[2]; /* variable length */
> +} __packed;
> +
> +/* SecurityMode flags */
> +#define SMB2_NEGOTIATE_SIGNING_ENABLED 0x0001
> +#define SMB2_NEGOTIATE_SIGNING_REQUIRED 0x0002
> +/* Capabilities flags */
> +#define SMB2_GLOBAL_CAP_DFS 0x00000001
> +#define SMB2_GLOBAL_CAP_LEASING 0x00000002 /* Resp only New to SMB2.1 */
> +#define SMB2_GLOBAL_CAP_LARGE_MTU 0X00000004 /* Resp only New to SMB2.1 */
> +
> +struct smb2_negotiate_rsp {
> + struct smb2_hdr hdr;
> + __le16 StructureSize; /* Must be 65 */
> + __le16 SecurityMode;
> + __le16 DialectRevision;
> + __le16 Reserved; /* MBZ */
> + __u8 ServerGUID[16];
> + __le32 Capabilities;
> + __le32 MaxTransactSize;
> + __le32 MaxReadSize;
> + __le32 MaxWriteSize;
> + __le64 SystemTime; /* MBZ */
> + __le64 ServerStartTime;
> + __le16 SecurityBufferOffset;
> + __le16 SecurityBufferLength;
> + __le32 Reserved2; /* may be any value, ignore */
> + __u8 Buffer[1]; /* variable length GSS security buffer */
> +} __packed;
> +
> #endif /* _SMB2PDU_H */
> diff --git a/fs/cifs/smb2proto.h b/fs/cifs/smb2proto.h
> index 19bf987..8817670 100644
> --- a/fs/cifs/smb2proto.h
> +++ b/fs/cifs/smb2proto.h
> @@ -35,10 +35,17 @@ struct statfs;
> extern int map_smb2_to_linux_error(char *buf, bool log_err);
> extern int smb2_check_message(char *buf, unsigned int length);
> extern unsigned int smb2_calc_size(struct smb2_hdr *hdr);
> +extern char *smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr);
>
> extern int smb2_check_receive(struct mid_q_entry *mid,
> struct TCP_Server_Info *server, bool log_error);
> extern int smb2_setup_request(struct cifs_ses *ses, struct kvec *iov,
> unsigned int nvec, struct mid_q_entry **ret_mid);
>
> +/*
> + * SMB2 Worker functions - most of protocol specific implementation details
> + * are contained within these calls.
> + */
> +extern int SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses);
> +
> #endif /* _SMB2PROTO_H */
Patch looks fine overall. A few nits here and there, but not worth
respinning unless you're in there for other reasons.
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
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