Add a SMB2 crediting algorithm, by default the same as Windows. Defaults to 128 credits.

Jeremy.

diff --git a/source3/include/local.h b/source3/include/local.h
index 6c9a8c3055c86340ef9529ec7daae2bf4c3fb02b..3014f613b2a65ac184b6789bfe6aa6ca63ea63d3 100644 (file)
--- a/source3/include/local.h
+++ b/source3/include/local.h
@@ -265,4 +265,9 @@
 #define CLIENT_NDR_PADDING_SIZE 8
 #define SERVER_NDR_PADDING_SIZE 8
 
+#define DEFAULT_SMB2_MAX_READ (1024*1024)
+#define DEFAULT_SMB2_MAX_WRITE (1024*1024)
+#define DEFAULT_SMB2_MAX_TRANSACT (1024*1024)
+#define DEFAULT_SMB2_MAX_CREDITS 128
+
 #endif

diff --git a/source3/include/proto.h b/source3/include/proto.h
index 3ef12158b84a057338b601105d1ab109568187eb..084d97f16e2879de0e4ada5e53e5070d1818e1b3 100644 (file)
--- a/source3/include/proto.h
+++ b/source3/include/proto.h
@@ -3351,6 +3351,7 @@ int lp_config_backend(void);
 int lp_smb2_max_read(void);
 int lp_smb2_max_write(void);
 int lp_smb2_max_trans(void);
+int lp_smb2_max_credits(void);
 char *lp_preexec(int );
 char *lp_postexec(int );
 char *lp_rootpreexec(int );

diff --git a/source3/param/loadparm.c b/source3/param/loadparm.c
index 807d074082657d812599af468e7ef30ea7431a4a..ced8223833724537e5537835ee80c8f32b46130e 100644 (file)
--- a/source3/param/loadparm.c
+++ b/source3/param/loadparm.c
@@ -380,6 +380,7 @@ struct global {
        int ismb2_max_read;
        int ismb2_max_write;
        int ismb2_max_trans;
+       int ismb2_max_credits;
        char *ncalrpc_dir;
 };
 
@@ -2635,6 +2636,15 @@ static struct parm_struct parm_table[] = {
                .enum_list      = NULL,
                .flags          = FLAG_ADVANCED,
        },
+       {
+               .label          = "smb2 max credits",
+               .type           = P_INTEGER,
+               .p_class        = P_GLOBAL,
+               .ptr            = &Globals.ismb2_max_credits,
+               .special        = NULL,
+               .enum_list      = NULL,
+               .flags          = FLAG_ADVANCED,
+       },
 
        {N_("Printing Options"), P_SEP, P_SEPARATOR},
 
@@ -5404,9 +5414,10 @@ static void init_globals(bool reinit_globals)
        Globals.bMapUntrustedToDomain = false;
        Globals.bMulticastDnsRegister = true;
 
-       Globals.ismb2_max_read = 1024*1024;
-       Globals.ismb2_max_write = 1024*1024;
-       Globals.ismb2_max_trans = 1024*1024;
+       Globals.ismb2_max_read = DEFAULT_SMB2_MAX_READ;
+       Globals.ismb2_max_write = DEFAULT_SMB2_MAX_WRITE;
+       Globals.ismb2_max_trans = DEFAULT_SMB2_MAX_TRANSACT;
+       Globals.ismb2_max_credits = DEFAULT_SMB2_MAX_CREDITS;
 
        string_set(&Globals.ncalrpc_dir, get_dyn_NCALRPCDIR());
 
@@ -5777,7 +5788,13 @@ FN_GLOBAL_INTEGER(lp_config_backend, &Globals.ConfigBackend)
 FN_GLOBAL_INTEGER(lp_smb2_max_read, &Globals.ismb2_max_read)
 FN_GLOBAL_INTEGER(lp_smb2_max_write, &Globals.ismb2_max_write)
 FN_GLOBAL_INTEGER(lp_smb2_max_trans, &Globals.ismb2_max_trans)
-
+int lp_smb2_max_credits(void)
+{
+       if (Globals.ismb2_max_credits == 0) {
+               Globals.ismb2_max_credits = DEFAULT_SMB2_MAX_CREDITS;
+       }
+       return Globals.ismb2_max_credits;
+}
 FN_LOCAL_STRING(lp_preexec, szPreExec)
 FN_LOCAL_STRING(lp_postexec, szPostExec)
 FN_LOCAL_STRING(lp_rootpreexec, szRootPreExec)

diff --git a/source3/smbd/globals.h b/source3/smbd/globals.h
index 5037b6d6b5f349ebd159c0533630c44d2f61f2d2..cb97cb5cd151b930916181b1acecbdfce731ba5d 100644 (file)
--- a/source3/smbd/globals.h
+++ b/source3/smbd/globals.h
@@ -581,7 +581,10 @@ struct smbd_server_connection {
                        bool blocking_lock_unlock_state;
                } locks;
                struct smbd_smb2_request *requests;
-               uint64_t credits_granted;
+               uint64_t seqnum_low;
+               uint32_t credits_granted;
+               uint32_t max_credits;
+               struct bitmap *credits_bitmap;
        } smb2;
 };
 

diff --git a/source3/smbd/smb2_server.c b/source3/smbd/smb2_server.c
index eb19d67b11551f9ef88de3adb661f5dde34febed..9ed74fca5ff734424ec3774456859eb2ca326e35 100644 (file)
--- a/source3/smbd/smb2_server.c
+++ b/source3/smbd/smb2_server.c
@@ -110,6 +110,13 @@ static NTSTATUS smbd_initialize_smb2(struct smbd_server_connection *sconn)
        }
        sconn->smb2.sessions.limit = 0x0000FFFE;
        sconn->smb2.sessions.list = NULL;
+       sconn->smb2.seqnum_low = 0;
+       sconn->smb2.credits_granted = 1;
+       sconn->smb2.max_credits = lp_smb2_max_credits();
+       sconn->smb2.credits_bitmap = bitmap_talloc(sconn, 2*sconn->smb2.max_credits);
+       if (sconn->smb2.credits_bitmap == NULL) {
+               return NT_STATUS_NO_MEMORY;
+       }
 
        ret = tstream_bsd_existing_socket(sconn, sconn->sock,
                                          &sconn->smb2.stream);
@@ -284,14 +291,70 @@ static NTSTATUS smbd_smb2_request_create(struct smbd_server_connection *sconn,
        return NT_STATUS_OK;
 }
 
-static NTSTATUS smbd_smb2_request_validate(struct smbd_smb2_request *req,
-                               uint16_t *p_creds_requested)
+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;
+
+       if (opcode == SMB2_OP_CANCEL) {
+               /* SMB2_CANCEL requests by definition resend messageids. */
+               return true;
+       }
+
+       if (message_id < sconn->smb2.seqnum_low ||
+                       message_id > (sconn->smb2.seqnum_low +
+                       (2*sconn->smb2.credits_granted))) {
+               DEBUG(0,("smb2_validate_message_id: bad message_id "
+                       "%llu (low = %llu, granted = %lu)\n",
+                       (unsigned long long)message_id,
+                       (unsigned long long)sconn->smb2.seqnum_low,
+                       (unsigned long)sconn->smb2.credits_granted ));
+               return false;
+       }
+
+       /* client just used a credit. */
+       SMB_ASSERT(sconn->smb2.credits_granted > 0);
+       sconn->smb2.credits_granted -= 1;
+
+       /* Mark the message_id as seen in the bitmap. */
+       bitmap_offset = (unsigned int)(message_id %
+                       (uint64_t)(sconn->smb2.max_credits * 2));
+       if (bitmap_query(credits_bm, bitmap_offset)) {
+               DEBUG(0,("smb2_validate_message_id: duplicate message_id "
+                       "%llu (bm offset %u)\n",
+                       (unsigned long long)message_id,
+                       bitmap_offset));
+               return false;
+       }
+       bitmap_set(credits_bm, bitmap_offset);
+
+       if (message_id == sconn->smb2.seqnum_low + 1) {
+               /* 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 + 1),
+                               bitmap_offset ));
+                       bitmap_clear(credits_bm, bitmap_offset);
+                       sconn->smb2.seqnum_low += 1;
+                       bitmap_offset = (bitmap_offset + 1) %
+                               (sconn->smb2.max_credits * 2);
+               }
+       }
+
+       return true;
+}
+
+static NTSTATUS smbd_smb2_request_validate(struct smbd_smb2_request *req)
 {
        int count;
        int idx;
        bool compound_related = false;
 
-       *p_creds_requested = 0;
        count = req->in.vector_count;
 
        if (count < 4) {
@@ -300,7 +363,6 @@ static NTSTATUS smbd_smb2_request_validate(struct smbd_smb2_request *req,
        }
 
        for (idx=1; idx < count; idx += 3) {
-               uint16_t creds_requested = 0;
                const uint8_t *inhdr = NULL;
                uint32_t flags;
 
@@ -314,16 +376,13 @@ static NTSTATUS smbd_smb2_request_validate(struct smbd_smb2_request *req,
 
                inhdr = (const uint8_t *)req->in.vector[idx].iov_base;
 
-               /* setup the SMB2 header */
+               /* Check the SMB2 header */
                if (IVAL(inhdr, SMB2_HDR_PROTOCOL_ID) != SMB2_MAGIC) {
                        return NT_STATUS_INVALID_PARAMETER;
                }
 
-               creds_requested = SVAL(inhdr, SMB2_HDR_CREDIT);
-               if (*p_creds_requested + creds_requested < creds_requested) {
-                       *p_creds_requested = 65535;
-               } else {
-                       *p_creds_requested += creds_requested;
+               if (!smb2_validate_message_id(req->sconn, inhdr)) {
+                       return NT_STATUS_INVALID_PARAMETER;
                }
 
                flags = IVAL(inhdr, SMB2_HDR_FLAGS);
@@ -374,6 +433,54 @@ static NTSTATUS smbd_smb2_request_validate(struct smbd_smb2_request *req,
        return NT_STATUS_OK;
 }
 
+static void smb2_set_operation_credit(struct smbd_server_connection *sconn,
+                       const struct iovec *in_vector,
+                       struct iovec *out_vector)
+{
+       uint8_t *outhdr = out_vector->iov_base;
+       uint16_t credits_requested = 0;
+       uint16_t credits_granted = 0;
+
+       if (in_vector != NULL) {
+               const uint8_t *inhdr = (const uint8_t *)in_vector->iov_base;
+               credits_requested = SVAL(inhdr, SMB2_HDR_CREDIT);
+       }
+
+       SMB_ASSERT(sconn->smb2.max_credits >= sconn->smb2.credits_granted);
+
+       /* Remember what we gave out. */
+       credits_granted = MIN(credits_requested, (sconn->smb2.max_credits -
+               sconn->smb2.credits_granted));
+
+       if (credits_granted == 0 && sconn->smb2.credits_granted == 0) {
+               /* Ensure the client credits can never drop to zero. */
+               credits_granted = 1;
+       }
+
+       SSVAL(outhdr, SMB2_HDR_CREDIT, credits_granted);
+       sconn->smb2.credits_granted += credits_granted;
+
+       DEBUG(10,("smb2_set_operation_credit: requested %u, "
+               "granted %u, total granted %u\n",
+               (unsigned int)credits_requested,
+               (unsigned int)credits_granted,
+               (unsigned int)sconn->smb2.credits_granted ));
+}
+
+static void smb2_calculate_credits(const struct smbd_smb2_request *inreq,
+                               struct smbd_smb2_request *outreq)
+{
+       int count, idx;
+
+       count = outreq->out.vector_count;
+
+       for (idx=1; idx < count; idx += 3) {
+               smb2_set_operation_credit(outreq->sconn,
+                       &inreq->in.vector[idx],
+                       &outreq->out.vector[idx]);
+       }
+}
+
 static NTSTATUS smbd_smb2_request_setup_out(struct smbd_smb2_request *req, uint16_t creds)
 {
        struct iovec *vector;
@@ -432,11 +539,6 @@ static NTSTATUS smbd_smb2_request_setup_out(struct smbd_smb2_request *req, uint1
                      NT_STATUS_V(NT_STATUS_INTERNAL_ERROR));
                SSVAL(outhdr, SMB2_HDR_OPCODE,
                      SVAL(inhdr, SMB2_HDR_OPCODE));
-               SSVAL(outhdr, SMB2_HDR_CREDIT,          creds);
-
-               /* Remember what we gave out. */
-               req->sconn->smb2.credits_granted += creds;
-
                SIVAL(outhdr, SMB2_HDR_FLAGS,
                      IVAL(inhdr, SMB2_HDR_FLAGS) | SMB2_HDR_FLAG_REDIRECT);
                SIVAL(outhdr, SMB2_HDR_NEXT_COMMAND,    next_command_ofs);
@@ -623,6 +725,9 @@ static NTSTATUS smb2_send_async_interim_response(const struct smbd_smb2_request
        /* And end the chain. */
        SIVAL(outhdr, SMB2_HDR_NEXT_COMMAND, 0);
 
+       /* Calculate outgoing credits */
+       smb2_calculate_credits(req, nreq);
+
        /* Re-sign if needed. */
        if (nreq->do_signing) {
                NTSTATUS status;
@@ -779,9 +884,6 @@ NTSTATUS smbd_smb2_request_pending_queue(struct smbd_smb2_request *req,
        SSVAL(hdr, SMB2_HDR_EPOCH, 0);
        SIVAL(hdr, SMB2_HDR_STATUS, NT_STATUS_V(STATUS_PENDING));
        SSVAL(hdr, SMB2_HDR_OPCODE, SVAL(reqhdr, SMB2_HDR_OPCODE));
-       SSVAL(hdr, SMB2_HDR_CREDIT, 5);
-
-       req->sconn->smb2.credits_granted += 5;
 
        SIVAL(hdr, SMB2_HDR_FLAGS, flags | SMB2_HDR_FLAG_ASYNC);
        SIVAL(hdr, SMB2_HDR_NEXT_COMMAND, 0);
@@ -799,6 +901,11 @@ NTSTATUS smbd_smb2_request_pending_queue(struct smbd_smb2_request *req,
        /* Match W2K8R2... */
        SCVAL(body, 0x08, 0x21);
 
+       /* Ensure we correctly go through crediting. */
+       smb2_set_operation_credit(req->sconn,
+                       NULL,
+                       &state->vector[1]);
+
        if (req->do_signing) {
                status = smb2_signing_sign_pdu(req->session->session_key,
                                        state->vector, 3);
@@ -876,8 +983,6 @@ NTSTATUS smbd_smb2_request_pending_queue(struct smbd_smb2_request *req,
        reqhdr = (uint8_t *)req->out.vector[1].iov_base;
        SIVAL(reqhdr, SMB2_HDR_FLAGS, flags | SMB2_HDR_FLAG_ASYNC);
        SBVAL(reqhdr, SMB2_HDR_PID, async_id);
-       /* Only return credits on the interim response. */
-       SSVAL(reqhdr, SMB2_HDR_CREDIT, 0);
 
        {
                const uint8_t *inhdr =
@@ -1331,13 +1436,18 @@ NTSTATUS smbd_smb2_request_dispatch(struct smbd_smb2_request *req)
 static NTSTATUS smbd_smb2_request_reply(struct smbd_smb2_request *req)
 {
        struct tevent_req *subreq;
+       int i = req->current_idx;
 
        req->subreq = NULL;
 
        smb2_setup_nbt_length(req->out.vector, req->out.vector_count);
 
+       /* Set credit for this operation. */
+       smb2_set_operation_credit(req->sconn,
+                       &req->in.vector[i],
+                       &req->out.vector[i]);
+
        if (req->do_signing) {
-               int i = req->current_idx;
                NTSTATUS status;
                status = smb2_signing_sign_pdu(req->session->session_key,
                                               &req->out.vector[i], 3);
@@ -2091,7 +2201,6 @@ void smbd_smb2_first_negprot(struct smbd_server_connection *sconn,
 
 static void smbd_smb2_request_incoming(struct tevent_req *subreq)
 {
-       uint16_t creds_requested = 0;
        struct smbd_server_connection *sconn = tevent_req_callback_data(subreq,
                                               struct smbd_server_connection);
        NTSTATUS status;
@@ -2118,7 +2227,7 @@ static void smbd_smb2_request_incoming(struct tevent_req *subreq)
        DEBUG(10,("smbd_smb2_request_incoming: idx[%d] of %d vectors\n",
                 req->current_idx, req->in.vector_count));
 
-       status = smbd_smb2_request_validate(req, &creds_requested);
+       status = smbd_smb2_request_validate(req);
        if (!NT_STATUS_IS_OK(status)) {
                smbd_server_connection_terminate(sconn, nt_errstr(status));
                return;