kernel_optimize_test/fs/cifs/smb2transport.c

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/*
* fs/cifs/smb2transport.c
*
* Copyright (C) International Business Machines Corp., 2002, 2011
* Etersoft, 2012
* Author(s): Steve French (sfrench@us.ibm.com)
* Jeremy Allison (jra@samba.org) 2006
* Pavel Shilovsky (pshilovsky@samba.org) 2012
*
* 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
*/
#include <linux/fs.h>
#include <linux/list.h>
#include <linux/wait.h>
#include <linux/net.h>
#include <linux/delay.h>
#include <linux/uaccess.h>
#include <asm/processor.h>
#include <linux/mempool.h>
#include <linux/highmem.h>
#include <crypto/aead.h>
#include "smb2pdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "smb2proto.h"
#include "cifs_debug.h"
#include "smb2status.h"
#include "smb2glob.h"
static int
smb2_crypto_shash_allocate(struct TCP_Server_Info *server)
{
return cifs_alloc_hash("hmac(sha256)",
&server->secmech.hmacsha256,
&server->secmech.sdeschmacsha256);
}
static int
smb3_crypto_shash_allocate(struct TCP_Server_Info *server)
{
struct cifs_secmech *p = &server->secmech;
int rc;
rc = cifs_alloc_hash("hmac(sha256)",
&p->hmacsha256,
&p->sdeschmacsha256);
if (rc)
goto err;
rc = cifs_alloc_hash("cmac(aes)", &p->cmacaes, &p->sdesccmacaes);
if (rc)
goto err;
return 0;
err:
cifs_free_hash(&p->hmacsha256, &p->sdeschmacsha256);
return rc;
}
int
smb311_crypto_shash_allocate(struct TCP_Server_Info *server)
{
struct cifs_secmech *p = &server->secmech;
int rc = 0;
rc = cifs_alloc_hash("hmac(sha256)",
&p->hmacsha256,
&p->sdeschmacsha256);
if (rc)
return rc;
rc = cifs_alloc_hash("cmac(aes)", &p->cmacaes, &p->sdesccmacaes);
if (rc)
goto err;
rc = cifs_alloc_hash("sha512", &p->sha512, &p->sdescsha512);
if (rc)
goto err;
return 0;
err:
cifs_free_hash(&p->cmacaes, &p->sdesccmacaes);
cifs_free_hash(&p->hmacsha256, &p->sdeschmacsha256);
return rc;
}
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
static
int smb2_get_sign_key(__u64 ses_id, struct TCP_Server_Info *server, u8 *key)
{
struct cifs_chan *chan;
struct cifs_ses *ses = NULL;
int i;
int rc = 0;
spin_lock(&cifs_tcp_ses_lock);
list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
if (ses->Suid == ses_id)
goto found;
}
}
cifs_server_dbg(VFS, "%s: Could not find session 0x%llx\n",
__func__, ses_id);
rc = -ENOENT;
goto out;
found:
if (ses->binding) {
/*
* If we are in the process of binding a new channel
* to an existing session, use the master connection
* session key
*/
memcpy(key, ses->smb3signingkey, SMB3_SIGN_KEY_SIZE);
goto out;
}
/*
* Otherwise, use the channel key.
*/
for (i = 0; i < ses->chan_count; i++) {
chan = ses->chans + i;
if (chan->server == server) {
memcpy(key, chan->signkey, SMB3_SIGN_KEY_SIZE);
goto out;
}
}
cifs_dbg(VFS,
"%s: Could not find channel signing key for session 0x%llx\n",
__func__, ses_id);
rc = -ENOENT;
out:
spin_unlock(&cifs_tcp_ses_lock);
return rc;
}
static struct cifs_ses *
smb2_find_smb_ses_unlocked(struct TCP_Server_Info *server, __u64 ses_id)
{
struct cifs_ses *ses;
list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
if (ses->Suid != ses_id)
continue;
return ses;
}
return NULL;
}
struct cifs_ses *
smb2_find_smb_ses(struct TCP_Server_Info *server, __u64 ses_id)
{
struct cifs_ses *ses;
spin_lock(&cifs_tcp_ses_lock);
ses = smb2_find_smb_ses_unlocked(server, ses_id);
spin_unlock(&cifs_tcp_ses_lock);
return ses;
}
static struct cifs_tcon *
smb2_find_smb_sess_tcon_unlocked(struct cifs_ses *ses, __u32 tid)
{
struct cifs_tcon *tcon;
list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
if (tcon->tid != tid)
continue;
++tcon->tc_count;
return tcon;
}
return NULL;
}
/*
* Obtain tcon corresponding to the tid in the given
* cifs_ses
*/
struct cifs_tcon *
smb2_find_smb_tcon(struct TCP_Server_Info *server, __u64 ses_id, __u32 tid)
{
struct cifs_ses *ses;
struct cifs_tcon *tcon;
spin_lock(&cifs_tcp_ses_lock);
ses = smb2_find_smb_ses_unlocked(server, ses_id);
if (!ses) {
spin_unlock(&cifs_tcp_ses_lock);
return NULL;
}
tcon = smb2_find_smb_sess_tcon_unlocked(ses, tid);
spin_unlock(&cifs_tcp_ses_lock);
return tcon;
}
int
smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
{
int rc;
unsigned char smb2_signature[SMB2_HMACSHA256_SIZE];
unsigned char *sigptr = smb2_signature;
struct kvec *iov = rqst->rq_iov;
struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)iov[0].iov_base;
struct cifs_ses *ses;
struct shash_desc *shash;
struct smb_rqst drqst;
ses = smb2_find_smb_ses(server, shdr->SessionId);
if (!ses) {
cifs_server_dbg(VFS, "%s: Could not find session\n", __func__);
return 0;
}
memset(smb2_signature, 0x0, SMB2_HMACSHA256_SIZE);
memset(shdr->Signature, 0x0, SMB2_SIGNATURE_SIZE);
rc = smb2_crypto_shash_allocate(server);
if (rc) {
cifs_server_dbg(VFS, "%s: sha256 alloc failed\n", __func__);
return rc;
}
rc = crypto_shash_setkey(server->secmech.hmacsha256,
ses->auth_key.response, SMB2_NTLMV2_SESSKEY_SIZE);
if (rc) {
cifs_server_dbg(VFS, "%s: Could not update with response\n", __func__);
return rc;
}
shash = &server->secmech.sdeschmacsha256->shash;
rc = crypto_shash_init(shash);
if (rc) {
cifs_server_dbg(VFS, "%s: Could not init sha256", __func__);
return rc;
}
/*
* For SMB2+, __cifs_calc_signature() expects to sign only the actual
* data, that is, iov[0] should not contain a rfc1002 length.
*
* Sign the rfc1002 length prior to passing the data (iov[1-N]) down to
* __cifs_calc_signature().
*/
drqst = *rqst;
if (drqst.rq_nvec >= 2 && iov[0].iov_len == 4) {
rc = crypto_shash_update(shash, iov[0].iov_base,
iov[0].iov_len);
if (rc) {
cifs_server_dbg(VFS, "%s: Could not update with payload\n",
__func__);
return rc;
}
drqst.rq_iov++;
drqst.rq_nvec--;
}
rc = __cifs_calc_signature(&drqst, server, sigptr, shash);
if (!rc)
memcpy(shdr->Signature, sigptr, SMB2_SIGNATURE_SIZE);
return rc;
}
static int generate_key(struct cifs_ses *ses, struct kvec label,
struct kvec context, __u8 *key, unsigned int key_size)
{
unsigned char zero = 0x0;
__u8 i[4] = {0, 0, 0, 1};
__u8 L[4] = {0, 0, 0, 128};
int rc = 0;
unsigned char prfhash[SMB2_HMACSHA256_SIZE];
unsigned char *hashptr = prfhash;
struct TCP_Server_Info *server = ses->server;
memset(prfhash, 0x0, SMB2_HMACSHA256_SIZE);
memset(key, 0x0, key_size);
rc = smb3_crypto_shash_allocate(server);
if (rc) {
cifs_server_dbg(VFS, "%s: crypto alloc failed\n", __func__);
goto smb3signkey_ret;
}
rc = crypto_shash_setkey(server->secmech.hmacsha256,
ses->auth_key.response, SMB2_NTLMV2_SESSKEY_SIZE);
if (rc) {
cifs_server_dbg(VFS, "%s: Could not set with session key\n", __func__);
goto smb3signkey_ret;
}
rc = crypto_shash_init(&server->secmech.sdeschmacsha256->shash);
if (rc) {
cifs_server_dbg(VFS, "%s: Could not init sign hmac\n", __func__);
goto smb3signkey_ret;
}
rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
i, 4);
if (rc) {
cifs_server_dbg(VFS, "%s: Could not update with n\n", __func__);
goto smb3signkey_ret;
}
rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
label.iov_base, label.iov_len);
if (rc) {
cifs_server_dbg(VFS, "%s: Could not update with label\n", __func__);
goto smb3signkey_ret;
}
rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
&zero, 1);
if (rc) {
cifs_server_dbg(VFS, "%s: Could not update with zero\n", __func__);
goto smb3signkey_ret;
}
rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
context.iov_base, context.iov_len);
if (rc) {
cifs_server_dbg(VFS, "%s: Could not update with context\n", __func__);
goto smb3signkey_ret;
}
rc = crypto_shash_update(&server->secmech.sdeschmacsha256->shash,
L, 4);
if (rc) {
cifs_server_dbg(VFS, "%s: Could not update with L\n", __func__);
goto smb3signkey_ret;
}
rc = crypto_shash_final(&server->secmech.sdeschmacsha256->shash,
hashptr);
if (rc) {
cifs_server_dbg(VFS, "%s: Could not generate sha256 hash\n", __func__);
goto smb3signkey_ret;
}
memcpy(key, hashptr, key_size);
smb3signkey_ret:
return rc;
}
struct derivation {
struct kvec label;
struct kvec context;
};
struct derivation_triplet {
struct derivation signing;
struct derivation encryption;
struct derivation decryption;
};
static int
generate_smb3signingkey(struct cifs_ses *ses,
const struct derivation_triplet *ptriplet)
{
int rc;
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
/*
* All channels use the same encryption/decryption keys but
* they have their own signing key.
*
* When we generate the keys, check if it is for a new channel
* (binding) in which case we only need to generate a signing
* key and store it in the channel as to not overwrite the
* master connection signing key stored in the session
*/
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
if (ses->binding) {
rc = generate_key(ses, ptriplet->signing.label,
ptriplet->signing.context,
cifs_ses_binding_channel(ses)->signkey,
SMB3_SIGN_KEY_SIZE);
if (rc)
return rc;
} else {
rc = generate_key(ses, ptriplet->signing.label,
ptriplet->signing.context,
ses->smb3signingkey,
SMB3_SIGN_KEY_SIZE);
if (rc)
return rc;
memcpy(ses->chans[0].signkey, ses->smb3signingkey,
SMB3_SIGN_KEY_SIZE);
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
rc = generate_key(ses, ptriplet->encryption.label,
ptriplet->encryption.context,
ses->smb3encryptionkey,
SMB3_SIGN_KEY_SIZE);
rc = generate_key(ses, ptriplet->decryption.label,
ptriplet->decryption.context,
ses->smb3decryptionkey,
SMB3_SIGN_KEY_SIZE);
if (rc)
return rc;
}
if (rc)
return rc;
#ifdef CONFIG_CIFS_DEBUG_DUMP_KEYS
cifs_dbg(VFS, "%s: dumping generated AES session keys\n", __func__);
/*
* The session id is opaque in terms of endianness, so we can't
* print it as a long long. we dump it as we got it on the wire
*/
cifs_dbg(VFS, "Session Id %*ph\n", (int)sizeof(ses->Suid),
&ses->Suid);
cifs_dbg(VFS, "Session Key %*ph\n",
SMB2_NTLMV2_SESSKEY_SIZE, ses->auth_key.response);
cifs_dbg(VFS, "Signing Key %*ph\n",
SMB3_SIGN_KEY_SIZE, ses->smb3signingkey);
cifs_dbg(VFS, "ServerIn Key %*ph\n",
SMB3_SIGN_KEY_SIZE, ses->smb3encryptionkey);
cifs_dbg(VFS, "ServerOut Key %*ph\n",
SMB3_SIGN_KEY_SIZE, ses->smb3decryptionkey);
#endif
return rc;
}
int
generate_smb30signingkey(struct cifs_ses *ses)
{
struct derivation_triplet triplet;
struct derivation *d;
d = &triplet.signing;
d->label.iov_base = "SMB2AESCMAC";
d->label.iov_len = 12;
d->context.iov_base = "SmbSign";
d->context.iov_len = 8;
d = &triplet.encryption;
d->label.iov_base = "SMB2AESCCM";
d->label.iov_len = 11;
d->context.iov_base = "ServerIn ";
d->context.iov_len = 10;
d = &triplet.decryption;
d->label.iov_base = "SMB2AESCCM";
d->label.iov_len = 11;
d->context.iov_base = "ServerOut";
d->context.iov_len = 10;
return generate_smb3signingkey(ses, &triplet);
}
int
generate_smb311signingkey(struct cifs_ses *ses)
{
struct derivation_triplet triplet;
struct derivation *d;
d = &triplet.signing;
d->label.iov_base = "SMBSigningKey";
d->label.iov_len = 14;
d->context.iov_base = ses->preauth_sha_hash;
d->context.iov_len = 64;
d = &triplet.encryption;
d->label.iov_base = "SMBC2SCipherKey";
d->label.iov_len = 16;
d->context.iov_base = ses->preauth_sha_hash;
d->context.iov_len = 64;
d = &triplet.decryption;
d->label.iov_base = "SMBS2CCipherKey";
d->label.iov_len = 16;
d->context.iov_base = ses->preauth_sha_hash;
d->context.iov_len = 64;
return generate_smb3signingkey(ses, &triplet);
}
int
smb3_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
{
int rc;
unsigned char smb3_signature[SMB2_CMACAES_SIZE];
unsigned char *sigptr = smb3_signature;
struct kvec *iov = rqst->rq_iov;
struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)iov[0].iov_base;
struct shash_desc *shash = &server->secmech.sdesccmacaes->shash;
struct smb_rqst drqst;
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
u8 key[SMB3_SIGN_KEY_SIZE];
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
rc = smb2_get_sign_key(shdr->SessionId, server, key);
if (rc)
return 0;
memset(smb3_signature, 0x0, SMB2_CMACAES_SIZE);
memset(shdr->Signature, 0x0, SMB2_SIGNATURE_SIZE);
rc = crypto_shash_setkey(server->secmech.cmacaes,
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
key, SMB2_CMACAES_SIZE);
if (rc) {
cifs_server_dbg(VFS, "%s: Could not set key for cmac aes\n", __func__);
return rc;
}
/*
* we already allocate sdesccmacaes when we init smb3 signing key,
* so unlike smb2 case we do not have to check here if secmech are
* initialized
*/
rc = crypto_shash_init(shash);
if (rc) {
cifs_server_dbg(VFS, "%s: Could not init cmac aes\n", __func__);
return rc;
}
/*
* For SMB2+, __cifs_calc_signature() expects to sign only the actual
* data, that is, iov[0] should not contain a rfc1002 length.
*
* Sign the rfc1002 length prior to passing the data (iov[1-N]) down to
* __cifs_calc_signature().
*/
drqst = *rqst;
if (drqst.rq_nvec >= 2 && iov[0].iov_len == 4) {
rc = crypto_shash_update(shash, iov[0].iov_base,
iov[0].iov_len);
if (rc) {
cifs_server_dbg(VFS, "%s: Could not update with payload\n",
__func__);
return rc;
}
drqst.rq_iov++;
drqst.rq_nvec--;
}
rc = __cifs_calc_signature(&drqst, server, sigptr, shash);
if (!rc)
memcpy(shdr->Signature, sigptr, SMB2_SIGNATURE_SIZE);
return rc;
}
/* must be called with server->srv_mutex held */
static int
smb2_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server)
{
int rc = 0;
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
struct smb2_sync_hdr *shdr;
struct smb2_sess_setup_req *ssr;
bool is_binding;
bool is_signed;
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
shdr = (struct smb2_sync_hdr *)rqst->rq_iov[0].iov_base;
ssr = (struct smb2_sess_setup_req *)shdr;
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
is_binding = shdr->Command == SMB2_SESSION_SETUP &&
(ssr->Flags & SMB2_SESSION_REQ_FLAG_BINDING);
is_signed = shdr->Flags & SMB2_FLAGS_SIGNED;
if (!is_signed)
return 0;
if (server->tcpStatus == CifsNeedNegotiate)
return 0;
if (!is_binding && !server->session_estab) {
strncpy(shdr->Signature, "BSRSPYL", 8);
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
return 0;
}
rc = server->ops->calc_signature(rqst, server);
return rc;
}
int
smb2_verify_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
{
unsigned int rc;
char server_response_sig[16];
struct smb2_sync_hdr *shdr =
(struct smb2_sync_hdr *)rqst->rq_iov[0].iov_base;
if ((shdr->Command == SMB2_NEGOTIATE) ||
(shdr->Command == SMB2_SESSION_SETUP) ||
(shdr->Command == SMB2_OPLOCK_BREAK) ||
server->ignore_signature ||
(!server->session_estab))
return 0;
/*
* BB what if signatures are supposed to be on for session but
* server does not send one? BB
*/
/* Do not need to verify session setups with signature "BSRSPYL " */
if (memcmp(shdr->Signature, "BSRSPYL ", 8) == 0)
cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
shdr->Command);
/*
* Save off the origiginal signature so we can modify the smb and check
* our calculated signature against what the server sent.
*/
memcpy(server_response_sig, shdr->Signature, SMB2_SIGNATURE_SIZE);
memset(shdr->Signature, 0, SMB2_SIGNATURE_SIZE);
mutex_lock(&server->srv_mutex);
rc = server->ops->calc_signature(rqst, server);
mutex_unlock(&server->srv_mutex);
if (rc)
return rc;
if (memcmp(server_response_sig, shdr->Signature, SMB2_SIGNATURE_SIZE))
return -EACCES;
else
return 0;
}
/*
* Set message id for the request. Should be called after wait_for_free_request
* and when srv_mutex is held.
*/
static inline void
smb2_seq_num_into_buf(struct TCP_Server_Info *server,
struct smb2_sync_hdr *shdr)
{
unsigned int i, num = le16_to_cpu(shdr->CreditCharge);
shdr->MessageId = get_next_mid64(server);
/* skip message numbers according to CreditCharge field */
for (i = 1; i < num; i++)
get_next_mid(server);
}
static struct mid_q_entry *
smb2_mid_entry_alloc(const struct smb2_sync_hdr *shdr,
struct TCP_Server_Info *server)
{
struct mid_q_entry *temp;
unsigned int credits = le16_to_cpu(shdr->CreditCharge);
if (server == NULL) {
cifs_dbg(VFS, "Null TCP session in smb2_mid_entry_alloc\n");
return NULL;
}
temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
memset(temp, 0, sizeof(struct mid_q_entry));
cifs: Fix use after free of a mid_q_entry With protocol version 2.0 mounts we have seen crashes with corrupt mid entries. Either the server->pending_mid_q list becomes corrupt with a cyclic reference in one element or a mid object fetched by the demultiplexer thread becomes overwritten during use. Code review identified a race between the demultiplexer thread and the request issuing thread. The demultiplexer thread seems to be written with the assumption that it is the sole user of the mid object until it calls the mid callback which either wakes the issuer task or deletes the mid. This assumption is not true because the issuer task can be woken up earlier by a signal. If the demultiplexer thread has proceeded as far as setting the mid_state to MID_RESPONSE_RECEIVED then the issuer thread will happily end up calling cifs_delete_mid while the demultiplexer thread still is using the mid object. Inserting a delay in the cifs demultiplexer thread widens the race window and makes reproduction of the race very easy: if (server->large_buf) buf = server->bigbuf; + usleep_range(500, 4000); server->lstrp = jiffies; To resolve this I think the proper solution involves putting a reference count on the mid object. This patch makes sure that the demultiplexer thread holds a reference until it has finished processing the transaction. Cc: stable@vger.kernel.org Signed-off-by: Lars Persson <larper@axis.com> Acked-by: Paulo Alcantara <palcantara@suse.de> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-06-25 20:05:25 +08:00
kref_init(&temp->refcount);
temp->mid = le64_to_cpu(shdr->MessageId);
temp->credits = credits > 0 ? credits : 1;
temp->pid = current->pid;
temp->command = shdr->Command; /* Always LE */
temp->when_alloc = jiffies;
temp->server = server;
/*
* The default is for the mid to be synchronous, so the
* default callback just wakes up the current task.
*/
temp->callback = cifs_wake_up_task;
temp->callback_data = current;
atomic_inc(&midCount);
temp->mid_state = MID_REQUEST_ALLOCATED;
trace_smb3_cmd_enter(shdr->TreeId, shdr->SessionId,
le16_to_cpu(shdr->Command), temp->mid);
return temp;
}
static int
smb2_get_mid_entry(struct cifs_ses *ses, struct TCP_Server_Info *server,
struct smb2_sync_hdr *shdr, struct mid_q_entry **mid)
{
if (server->tcpStatus == CifsExiting)
return -ENOENT;
if (server->tcpStatus == CifsNeedReconnect) {
cifs_dbg(FYI, "tcp session dead - return to caller to retry\n");
return -EAGAIN;
}
if (server->tcpStatus == CifsNeedNegotiate &&
shdr->Command != SMB2_NEGOTIATE)
return -EAGAIN;
if (ses->status == CifsNew) {
if ((shdr->Command != SMB2_SESSION_SETUP) &&
(shdr->Command != SMB2_NEGOTIATE))
return -EAGAIN;
/* else ok - we are setting up session */
}
if (ses->status == CifsExiting) {
if (shdr->Command != SMB2_LOGOFF)
return -EAGAIN;
/* else ok - we are shutting down the session */
}
*mid = smb2_mid_entry_alloc(shdr, server);
if (*mid == NULL)
return -ENOMEM;
spin_lock(&GlobalMid_Lock);
list_add_tail(&(*mid)->qhead, &server->pending_mid_q);
spin_unlock(&GlobalMid_Lock);
return 0;
}
int
smb2_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
bool log_error)
{
unsigned int len = mid->resp_buf_size;
struct kvec iov[1];
struct smb_rqst rqst = { .rq_iov = iov,
.rq_nvec = 1 };
iov[0].iov_base = (char *)mid->resp_buf;
iov[0].iov_len = len;
dump_smb(mid->resp_buf, min_t(u32, 80, len));
/* convert the length into a more usable form */
if (len > 24 && server->sign && !mid->decrypted) {
int rc;
rc = smb2_verify_signature(&rqst, server);
if (rc)
cifs_server_dbg(VFS, "SMB signature verification returned error = %d\n",
rc);
}
return map_smb2_to_linux_error(mid->resp_buf, log_error);
}
struct mid_q_entry *
smb2_setup_request(struct cifs_ses *ses, struct TCP_Server_Info *server,
struct smb_rqst *rqst)
{
int rc;
struct smb2_sync_hdr *shdr =
(struct smb2_sync_hdr *)rqst->rq_iov[0].iov_base;
struct mid_q_entry *mid;
smb2_seq_num_into_buf(server, shdr);
rc = smb2_get_mid_entry(ses, server, shdr, &mid);
if (rc) {
revert_current_mid_from_hdr(server, shdr);
return ERR_PTR(rc);
}
rc = smb2_sign_rqst(rqst, server);
if (rc) {
revert_current_mid_from_hdr(server, shdr);
cifs_delete_mid(mid);
return ERR_PTR(rc);
}
return mid;
}
struct mid_q_entry *
smb2_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst)
{
int rc;
struct smb2_sync_hdr *shdr =
(struct smb2_sync_hdr *)rqst->rq_iov[0].iov_base;
struct mid_q_entry *mid;
if (server->tcpStatus == CifsNeedNegotiate &&
shdr->Command != SMB2_NEGOTIATE)
return ERR_PTR(-EAGAIN);
smb2_seq_num_into_buf(server, shdr);
mid = smb2_mid_entry_alloc(shdr, server);
if (mid == NULL) {
revert_current_mid_from_hdr(server, shdr);
return ERR_PTR(-ENOMEM);
}
rc = smb2_sign_rqst(rqst, server);
if (rc) {
revert_current_mid_from_hdr(server, shdr);
DeleteMidQEntry(mid);
return ERR_PTR(rc);
}
return mid;
}
int
smb3_crypto_aead_allocate(struct TCP_Server_Info *server)
{
struct crypto_aead *tfm;
if (!server->secmech.ccmaesencrypt) {
if (server->cipher_type == SMB2_ENCRYPTION_AES128_GCM)
tfm = crypto_alloc_aead("gcm(aes)", 0, 0);
else
tfm = crypto_alloc_aead("ccm(aes)", 0, 0);
if (IS_ERR(tfm)) {
cifs_server_dbg(VFS, "%s: Failed to alloc encrypt aead\n",
__func__);
return PTR_ERR(tfm);
}
server->secmech.ccmaesencrypt = tfm;
}
if (!server->secmech.ccmaesdecrypt) {
if (server->cipher_type == SMB2_ENCRYPTION_AES128_GCM)
tfm = crypto_alloc_aead("gcm(aes)", 0, 0);
else
tfm = crypto_alloc_aead("ccm(aes)", 0, 0);
if (IS_ERR(tfm)) {
crypto_free_aead(server->secmech.ccmaesencrypt);
server->secmech.ccmaesencrypt = NULL;
cifs_server_dbg(VFS, "%s: Failed to alloc decrypt aead\n",
__func__);
return PTR_ERR(tfm);
}
server->secmech.ccmaesdecrypt = tfm;
}
return 0;
}