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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /fs/smb/client/smb2transport.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/smb/client/smb2transport.c')
-rw-r--r--fs/smb/client/smb2transport.c947
1 files changed, 947 insertions, 0 deletions
diff --git a/fs/smb/client/smb2transport.c b/fs/smb/client/smb2transport.c
new file mode 100644
index 0000000000..5a3ca62d2f
--- /dev/null
+++ b/fs/smb/client/smb2transport.c
@@ -0,0 +1,947 @@
+// SPDX-License-Identifier: LGPL-2.1
+/*
+ *
+ * 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
+ *
+ */
+
+#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 "cifsglob.h"
+#include "cifsproto.h"
+#include "smb2proto.h"
+#include "cifs_debug.h"
+#include "smb2status.h"
+#include "smb2glob.h"
+
+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);
+ if (rc)
+ goto err;
+
+ rc = cifs_alloc_hash("cmac(aes)", &p->aes_cmac);
+ if (rc)
+ goto err;
+
+ return 0;
+err:
+ cifs_free_hash(&p->hmacsha256);
+ 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);
+ if (rc)
+ return rc;
+
+ rc = cifs_alloc_hash("cmac(aes)", &p->aes_cmac);
+ if (rc)
+ goto err;
+
+ rc = cifs_alloc_hash("sha512", &p->sha512);
+ if (rc)
+ goto err;
+
+ return 0;
+
+err:
+ cifs_free_hash(&p->aes_cmac);
+ cifs_free_hash(&p->hmacsha256);
+ return rc;
+}
+
+
+static
+int smb2_get_sign_key(__u64 ses_id, struct TCP_Server_Info *server, u8 *key)
+{
+ struct cifs_chan *chan;
+ struct TCP_Server_Info *pserver;
+ struct cifs_ses *ses = NULL;
+ int i;
+ int rc = 0;
+ bool is_binding = false;
+
+ spin_lock(&cifs_tcp_ses_lock);
+
+ /* If server is a channel, select the primary channel */
+ pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
+
+ list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
+ if (ses->Suid == ses_id)
+ goto found;
+ }
+ trace_smb3_ses_not_found(ses_id);
+ cifs_server_dbg(FYI, "%s: Could not find session 0x%llx\n",
+ __func__, ses_id);
+ rc = -ENOENT;
+ goto out;
+
+found:
+ spin_lock(&ses->ses_lock);
+ spin_lock(&ses->chan_lock);
+
+ is_binding = (cifs_chan_needs_reconnect(ses, server) &&
+ ses->ses_status == SES_GOOD);
+ if (is_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);
+ spin_unlock(&ses->chan_lock);
+ spin_unlock(&ses->ses_lock);
+ 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);
+ spin_unlock(&ses->chan_lock);
+ spin_unlock(&ses->ses_lock);
+ goto out;
+ }
+ }
+ spin_unlock(&ses->chan_lock);
+ spin_unlock(&ses->ses_lock);
+
+ 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 TCP_Server_Info *pserver;
+ struct cifs_ses *ses;
+
+ /* If server is a channel, select the primary channel */
+ pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
+
+ list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
+ if (ses->Suid != ses_id)
+ continue;
+
+ spin_lock(&ses->ses_lock);
+ if (ses->ses_status == SES_EXITING) {
+ spin_unlock(&ses->ses_lock);
+ continue;
+ }
+ cifs_smb_ses_inc_refcount(ses);
+ spin_unlock(&ses->ses_lock);
+ 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);
+ if (!tcon) {
+ cifs_put_smb_ses(ses);
+ spin_unlock(&cifs_tcp_ses_lock);
+ return NULL;
+ }
+ spin_unlock(&cifs_tcp_ses_lock);
+ /* tcon already has a ref to ses, so we don't need ses anymore */
+ cifs_put_smb_ses(ses);
+
+ return tcon;
+}
+
+int
+smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server,
+ bool allocate_crypto)
+{
+ int rc;
+ unsigned char smb2_signature[SMB2_HMACSHA256_SIZE];
+ unsigned char *sigptr = smb2_signature;
+ struct kvec *iov = rqst->rq_iov;
+ struct smb2_hdr *shdr = (struct smb2_hdr *)iov[0].iov_base;
+ struct cifs_ses *ses;
+ struct shash_desc *shash = NULL;
+ struct smb_rqst drqst;
+
+ ses = smb2_find_smb_ses(server, le64_to_cpu(shdr->SessionId));
+ if (unlikely(!ses)) {
+ cifs_server_dbg(VFS, "%s: Could not find session\n", __func__);
+ return -ENOENT;
+ }
+
+ memset(smb2_signature, 0x0, SMB2_HMACSHA256_SIZE);
+ memset(shdr->Signature, 0x0, SMB2_SIGNATURE_SIZE);
+
+ if (allocate_crypto) {
+ rc = cifs_alloc_hash("hmac(sha256)", &shash);
+ if (rc) {
+ cifs_server_dbg(VFS,
+ "%s: sha256 alloc failed\n", __func__);
+ goto out;
+ }
+ } else {
+ shash = server->secmech.hmacsha256;
+ }
+
+ rc = crypto_shash_setkey(shash->tfm, ses->auth_key.response,
+ SMB2_NTLMV2_SESSKEY_SIZE);
+ if (rc) {
+ cifs_server_dbg(VFS,
+ "%s: Could not update with response\n",
+ __func__);
+ goto out;
+ }
+
+ rc = crypto_shash_init(shash);
+ if (rc) {
+ cifs_server_dbg(VFS, "%s: Could not init sha256", __func__);
+ goto out;
+ }
+
+ /*
+ * 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__);
+ goto out;
+ }
+ drqst.rq_iov++;
+ drqst.rq_nvec--;
+ }
+
+ rc = __cifs_calc_signature(&drqst, server, sigptr, shash);
+ if (!rc)
+ memcpy(shdr->Signature, sigptr, SMB2_SIGNATURE_SIZE);
+
+out:
+ if (allocate_crypto)
+ cifs_free_hash(&shash);
+ if (ses)
+ cifs_put_smb_ses(ses);
+ 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 L128[4] = {0, 0, 0, 128};
+ __u8 L256[4] = {0, 0, 1, 0};
+ 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->tfm,
+ 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.hmacsha256);
+ if (rc) {
+ cifs_server_dbg(VFS, "%s: Could not init sign hmac\n", __func__);
+ goto smb3signkey_ret;
+ }
+
+ rc = crypto_shash_update(server->secmech.hmacsha256, 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.hmacsha256, 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.hmacsha256, &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.hmacsha256, context.iov_base, context.iov_len);
+ if (rc) {
+ cifs_server_dbg(VFS, "%s: Could not update with context\n", __func__);
+ goto smb3signkey_ret;
+ }
+
+ if ((server->cipher_type == SMB2_ENCRYPTION_AES256_CCM) ||
+ (server->cipher_type == SMB2_ENCRYPTION_AES256_GCM)) {
+ rc = crypto_shash_update(server->secmech.hmacsha256, L256, 4);
+ } else {
+ rc = crypto_shash_update(server->secmech.hmacsha256, L128, 4);
+ }
+ if (rc) {
+ cifs_server_dbg(VFS, "%s: Could not update with L\n", __func__);
+ goto smb3signkey_ret;
+ }
+
+ rc = crypto_shash_final(server->secmech.hmacsha256, 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,
+ struct TCP_Server_Info *server,
+ const struct derivation_triplet *ptriplet)
+{
+ int rc;
+ bool is_binding = false;
+ int chan_index = 0;
+
+ spin_lock(&ses->ses_lock);
+ spin_lock(&ses->chan_lock);
+ is_binding = (cifs_chan_needs_reconnect(ses, server) &&
+ ses->ses_status == SES_GOOD);
+
+ chan_index = cifs_ses_get_chan_index(ses, server);
+ if (chan_index == CIFS_INVAL_CHAN_INDEX) {
+ spin_unlock(&ses->chan_lock);
+ spin_unlock(&ses->ses_lock);
+
+ return -EINVAL;
+ }
+
+ spin_unlock(&ses->chan_lock);
+ spin_unlock(&ses->ses_lock);
+
+ /*
+ * 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
+ */
+
+ if (is_binding) {
+ rc = generate_key(ses, ptriplet->signing.label,
+ ptriplet->signing.context,
+ ses->chans[chan_index].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;
+
+ /* safe to access primary channel, since it will never go away */
+ spin_lock(&ses->chan_lock);
+ memcpy(ses->chans[chan_index].signkey, ses->smb3signingkey,
+ SMB3_SIGN_KEY_SIZE);
+ spin_unlock(&ses->chan_lock);
+
+ rc = generate_key(ses, ptriplet->encryption.label,
+ ptriplet->encryption.context,
+ ses->smb3encryptionkey,
+ SMB3_ENC_DEC_KEY_SIZE);
+ if (rc)
+ return rc;
+ rc = generate_key(ses, ptriplet->decryption.label,
+ ptriplet->decryption.context,
+ ses->smb3decryptionkey,
+ SMB3_ENC_DEC_KEY_SIZE);
+ 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, "Cipher type %d\n", server->cipher_type);
+ 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);
+ if ((server->cipher_type == SMB2_ENCRYPTION_AES256_CCM) ||
+ (server->cipher_type == SMB2_ENCRYPTION_AES256_GCM)) {
+ cifs_dbg(VFS, "ServerIn Key %*ph\n",
+ SMB3_GCM256_CRYPTKEY_SIZE, ses->smb3encryptionkey);
+ cifs_dbg(VFS, "ServerOut Key %*ph\n",
+ SMB3_GCM256_CRYPTKEY_SIZE, ses->smb3decryptionkey);
+ } else {
+ cifs_dbg(VFS, "ServerIn Key %*ph\n",
+ SMB3_GCM128_CRYPTKEY_SIZE, ses->smb3encryptionkey);
+ cifs_dbg(VFS, "ServerOut Key %*ph\n",
+ SMB3_GCM128_CRYPTKEY_SIZE, ses->smb3decryptionkey);
+ }
+#endif
+ return rc;
+}
+
+int
+generate_smb30signingkey(struct cifs_ses *ses,
+ struct TCP_Server_Info *server)
+
+{
+ 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, server, &triplet);
+}
+
+int
+generate_smb311signingkey(struct cifs_ses *ses,
+ struct TCP_Server_Info *server)
+
+{
+ 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, server, &triplet);
+}
+
+int
+smb3_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server,
+ bool allocate_crypto)
+{
+ int rc;
+ unsigned char smb3_signature[SMB2_CMACAES_SIZE];
+ unsigned char *sigptr = smb3_signature;
+ struct kvec *iov = rqst->rq_iov;
+ struct smb2_hdr *shdr = (struct smb2_hdr *)iov[0].iov_base;
+ struct shash_desc *shash = NULL;
+ struct smb_rqst drqst;
+ u8 key[SMB3_SIGN_KEY_SIZE];
+
+ rc = smb2_get_sign_key(le64_to_cpu(shdr->SessionId), server, key);
+ if (unlikely(rc)) {
+ cifs_server_dbg(FYI, "%s: Could not get signing key\n", __func__);
+ return rc;
+ }
+
+ if (allocate_crypto) {
+ rc = cifs_alloc_hash("cmac(aes)", &shash);
+ if (rc)
+ return rc;
+ } else {
+ shash = server->secmech.aes_cmac;
+ }
+
+ memset(smb3_signature, 0x0, SMB2_CMACAES_SIZE);
+ memset(shdr->Signature, 0x0, SMB2_SIGNATURE_SIZE);
+
+ rc = crypto_shash_setkey(shash->tfm, key, SMB2_CMACAES_SIZE);
+ if (rc) {
+ cifs_server_dbg(VFS, "%s: Could not set key for cmac aes\n", __func__);
+ goto out;
+ }
+
+ /*
+ * we already allocate aes_cmac 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__);
+ goto out;
+ }
+
+ /*
+ * 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__);
+ goto out;
+ }
+ drqst.rq_iov++;
+ drqst.rq_nvec--;
+ }
+
+ rc = __cifs_calc_signature(&drqst, server, sigptr, shash);
+ if (!rc)
+ memcpy(shdr->Signature, sigptr, SMB2_SIGNATURE_SIZE);
+
+out:
+ if (allocate_crypto)
+ cifs_free_hash(&shash);
+ 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;
+ struct smb2_hdr *shdr;
+ struct smb2_sess_setup_req *ssr;
+ bool is_binding;
+ bool is_signed;
+
+ shdr = (struct smb2_hdr *)rqst->rq_iov[0].iov_base;
+ ssr = (struct smb2_sess_setup_req *)shdr;
+
+ 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;
+ spin_lock(&server->srv_lock);
+ if (server->ops->need_neg &&
+ server->ops->need_neg(server)) {
+ spin_unlock(&server->srv_lock);
+ return 0;
+ }
+ spin_unlock(&server->srv_lock);
+ if (!is_binding && !server->session_estab) {
+ strncpy(shdr->Signature, "BSRSPYL", 8);
+ return 0;
+ }
+
+ rc = server->ops->calc_signature(rqst, server, false);
+
+ return rc;
+}
+
+int
+smb2_verify_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
+{
+ unsigned int rc;
+ char server_response_sig[SMB2_SIGNATURE_SIZE];
+ struct smb2_hdr *shdr =
+ (struct smb2_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);
+
+ rc = server->ops->calc_signature(rqst, server, true);
+
+ if (rc)
+ return rc;
+
+ if (memcmp(server_response_sig, shdr->Signature, SMB2_SIGNATURE_SIZE)) {
+ cifs_dbg(VFS, "sign fail cmd 0x%x message id 0x%llx\n",
+ shdr->Command, shdr->MessageId);
+ 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_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_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));
+ 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.
+ */
+ get_task_struct(current);
+ temp->creator = current;
+ temp->callback = cifs_wake_up_task;
+ temp->callback_data = current;
+
+ atomic_inc(&mid_count);
+ temp->mid_state = MID_REQUEST_ALLOCATED;
+ trace_smb3_cmd_enter(le32_to_cpu(shdr->Id.SyncId.TreeId),
+ le64_to_cpu(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_hdr *shdr, struct mid_q_entry **mid)
+{
+ spin_lock(&server->srv_lock);
+ if (server->tcpStatus == CifsExiting) {
+ spin_unlock(&server->srv_lock);
+ return -ENOENT;
+ }
+
+ if (server->tcpStatus == CifsNeedReconnect) {
+ spin_unlock(&server->srv_lock);
+ cifs_dbg(FYI, "tcp session dead - return to caller to retry\n");
+ return -EAGAIN;
+ }
+
+ if (server->tcpStatus == CifsNeedNegotiate &&
+ shdr->Command != SMB2_NEGOTIATE) {
+ spin_unlock(&server->srv_lock);
+ return -EAGAIN;
+ }
+ spin_unlock(&server->srv_lock);
+
+ spin_lock(&ses->ses_lock);
+ if (ses->ses_status == SES_NEW) {
+ if ((shdr->Command != SMB2_SESSION_SETUP) &&
+ (shdr->Command != SMB2_NEGOTIATE)) {
+ spin_unlock(&ses->ses_lock);
+ return -EAGAIN;
+ }
+ /* else ok - we are setting up session */
+ }
+
+ if (ses->ses_status == SES_EXITING) {
+ if (shdr->Command != SMB2_LOGOFF) {
+ spin_unlock(&ses->ses_lock);
+ return -EAGAIN;
+ }
+ /* else ok - we are shutting down the session */
+ }
+ spin_unlock(&ses->ses_lock);
+
+ *mid = smb2_mid_entry_alloc(shdr, server);
+ if (*mid == NULL)
+ return -ENOMEM;
+ spin_lock(&server->mid_lock);
+ list_add_tail(&(*mid)->qhead, &server->pending_mid_q);
+ spin_unlock(&server->mid_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_hdr *shdr =
+ (struct smb2_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);
+ 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_hdr *shdr =
+ (struct smb2_hdr *)rqst->rq_iov[0].iov_base;
+ struct mid_q_entry *mid;
+
+ spin_lock(&server->srv_lock);
+ if (server->tcpStatus == CifsNeedNegotiate &&
+ shdr->Command != SMB2_NEGOTIATE) {
+ spin_unlock(&server->srv_lock);
+ return ERR_PTR(-EAGAIN);
+ }
+ spin_unlock(&server->srv_lock);
+
+ 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);
+ release_mid(mid);
+ return ERR_PTR(rc);
+ }
+
+ return mid;
+}
+
+int
+smb3_crypto_aead_allocate(struct TCP_Server_Info *server)
+{
+ struct crypto_aead *tfm;
+
+ if (!server->secmech.enc) {
+ if ((server->cipher_type == SMB2_ENCRYPTION_AES128_GCM) ||
+ (server->cipher_type == SMB2_ENCRYPTION_AES256_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 alloc encrypt aead\n",
+ __func__);
+ return PTR_ERR(tfm);
+ }
+ server->secmech.enc = tfm;
+ }
+
+ if (!server->secmech.dec) {
+ if ((server->cipher_type == SMB2_ENCRYPTION_AES128_GCM) ||
+ (server->cipher_type == SMB2_ENCRYPTION_AES256_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.enc);
+ server->secmech.enc = NULL;
+ cifs_server_dbg(VFS, "%s: Failed to alloc decrypt aead\n",
+ __func__);
+ return PTR_ERR(tfm);
+ }
+ server->secmech.dec = tfm;
+ }
+
+ return 0;
+}