diff options
Diffstat (limited to 'fs/cifs')
| -rw-r--r-- | fs/cifs/Kconfig | 1 | ||||
| -rw-r--r-- | fs/cifs/cifsencrypt.c | 30 | ||||
| -rw-r--r-- | fs/cifs/cifsglob.h | 2 | ||||
| -rw-r--r-- | fs/cifs/cifsproto.h | 1 | ||||
| -rw-r--r-- | fs/cifs/smb2glob.h | 4 | ||||
| -rw-r--r-- | fs/cifs/smb2pdu.c | 52 | ||||
| -rw-r--r-- | fs/cifs/smb2proto.h | 2 | ||||
| -rw-r--r-- | fs/cifs/smb2transport.c | 165 | ||||
| -rw-r--r-- | fs/cifs/transport.c | 24 |
9 files changed, 253 insertions, 28 deletions
diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig index a08306a8bec9..802930179c2b 100644 --- a/fs/cifs/Kconfig +++ b/fs/cifs/Kconfig @@ -9,6 +9,7 @@ config CIFS select CRYPTO_ARC4 select CRYPTO_ECB select CRYPTO_DES + select CRYPTO_SHA256 help This is the client VFS module for the Common Internet File System (CIFS) protocol which is the successor to the Server Message Block diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c index 6a0d741159f0..724738c1a560 100644 --- a/fs/cifs/cifsencrypt.c +++ b/fs/cifs/cifsencrypt.c @@ -686,12 +686,17 @@ calc_seckey(struct cifs_ses *ses) void cifs_crypto_shash_release(struct TCP_Server_Info *server) { + if (server->secmech.hmacsha256) + crypto_free_shash(server->secmech.hmacsha256); + if (server->secmech.md5) crypto_free_shash(server->secmech.md5); if (server->secmech.hmacmd5) crypto_free_shash(server->secmech.hmacmd5); + kfree(server->secmech.sdeschmacsha256); + kfree(server->secmech.sdeschmacmd5); kfree(server->secmech.sdescmd5); @@ -716,6 +721,13 @@ cifs_crypto_shash_allocate(struct TCP_Server_Info *server) goto crypto_allocate_md5_fail; } + server->secmech.hmacsha256 = crypto_alloc_shash("hmac(sha256)", 0, 0); + if (IS_ERR(server->secmech.hmacsha256)) { + cERROR(1, "could not allocate crypto hmacsha256\n"); + rc = PTR_ERR(server->secmech.hmacsha256); + goto crypto_allocate_hmacsha256_fail; + } + size = sizeof(struct shash_desc) + crypto_shash_descsize(server->secmech.hmacmd5); server->secmech.sdeschmacmd5 = kmalloc(size, GFP_KERNEL); @@ -727,7 +739,6 @@ cifs_crypto_shash_allocate(struct TCP_Server_Info *server) server->secmech.sdeschmacmd5->shash.tfm = server->secmech.hmacmd5; server->secmech.sdeschmacmd5->shash.flags = 0x0; - size = sizeof(struct shash_desc) + crypto_shash_descsize(server->secmech.md5); server->secmech.sdescmd5 = kmalloc(size, GFP_KERNEL); @@ -739,12 +750,29 @@ cifs_crypto_shash_allocate(struct TCP_Server_Info *server) server->secmech.sdescmd5->shash.tfm = server->secmech.md5; server->secmech.sdescmd5->shash.flags = 0x0; + size = sizeof(struct shash_desc) + + crypto_shash_descsize(server->secmech.hmacsha256); + server->secmech.sdeschmacsha256 = kmalloc(size, GFP_KERNEL); + if (!server->secmech.sdeschmacsha256) { + cERROR(1, "%s: Can't alloc hmacsha256\n", __func__); + rc = -ENOMEM; + goto crypto_allocate_hmacsha256_sdesc_fail; + } + server->secmech.sdeschmacsha256->shash.tfm = server->secmech.hmacsha256; + server->secmech.sdeschmacsha256->shash.flags = 0x0; + return 0; +crypto_allocate_hmacsha256_sdesc_fail: + kfree(server->secmech.sdescmd5); + crypto_allocate_md5_sdesc_fail: kfree(server->secmech.sdeschmacmd5); crypto_allocate_hmacmd5_sdesc_fail: + crypto_free_shash(server->secmech.hmacsha256); + +crypto_allocate_hmacsha256_fail: crypto_free_shash(server->secmech.md5); crypto_allocate_md5_fail: diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index 48c7c83a7a99..6217df707909 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -128,8 +128,10 @@ struct sdesc { struct cifs_secmech { struct crypto_shash *hmacmd5; /* hmac-md5 hash function */ struct crypto_shash *md5; /* md5 hash function */ + struct crypto_shash *hmacsha256; /* hmac-sha256 hash function */ struct sdesc *sdeschmacmd5; /* ctxt to generate ntlmv2 hash, CR1 */ struct sdesc *sdescmd5; /* ctxt to generate cifs/smb signature */ + struct sdesc *sdeschmacsha256; /* ctxt to generate smb2 signature */ }; /* per smb session structure/fields */ diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h index f20d0c8ee7ce..541738fcaebc 100644 --- a/fs/cifs/cifsproto.h +++ b/fs/cifs/cifsproto.h @@ -65,6 +65,7 @@ extern char *cifs_compose_mount_options(const char *sb_mountdata, extern struct mid_q_entry *AllocMidQEntry(const struct smb_hdr *smb_buffer, struct TCP_Server_Info *server); extern void DeleteMidQEntry(struct mid_q_entry *midEntry); +extern void cifs_delete_mid(struct mid_q_entry *mid); extern void cifs_wake_up_task(struct mid_q_entry *mid); extern int cifs_call_async(struct TCP_Server_Info *server, struct kvec *iov, unsigned int nvec, mid_receive_t *receive, diff --git a/fs/cifs/smb2glob.h b/fs/cifs/smb2glob.h index 11505d73ff32..8635574ea8b6 100644 --- a/fs/cifs/smb2glob.h +++ b/fs/cifs/smb2glob.h @@ -47,4 +47,8 @@ #define END_OF_CHAIN 4 #define RELATED_REQUEST 8 +#define SMB2_SIGNATURE_SIZE (16) +#define SMB2_NTLMV2_SESSKEY_SIZE (16) +#define SMB2_HMACSHA256_SIZE (32) + #endif /* _SMB2_GLOB_H */ diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 00dc45a7881c..30c92c847fe8 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -118,9 +118,9 @@ smb2_hdr_assemble(struct smb2_hdr *hdr, __le16 smb2_cmd /* command */ , /* BB how does SMB2 do case sensitive? */ /* if (tcon->nocase) hdr->Flags |= SMBFLG_CASELESS; */ - /* if (tcon->ses && tcon->ses->server && + if (tcon->ses && tcon->ses->server && (tcon->ses->server->sec_mode & SECMODE_SIGN_REQUIRED)) - hdr->Flags |= SMB2_FLAGS_SIGNED; */ + hdr->Flags |= SMB2_FLAGS_SIGNED; out: pdu->StructureSize2 = cpu_to_le16(parmsize); return; @@ -441,6 +441,38 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses) rc = -EIO; goto neg_exit; } + + cFYI(1, "sec_flags 0x%x", sec_flags); + if (sec_flags & CIFSSEC_MUST_SIGN) { + cFYI(1, "Signing required"); + if (!(server->sec_mode & (SMB2_NEGOTIATE_SIGNING_REQUIRED | + SMB2_NEGOTIATE_SIGNING_ENABLED))) { + cERROR(1, "signing required but server lacks support"); + rc = -EOPNOTSUPP; + goto neg_exit; + } + server->sec_mode |= SECMODE_SIGN_REQUIRED; + } else if (sec_flags & CIFSSEC_MAY_SIGN) { + cFYI(1, "Signing optional"); + if (server->sec_mode & SMB2_NEGOTIATE_SIGNING_REQUIRED) { + cFYI(1, "Server requires signing"); + server->sec_mode |= SECMODE_SIGN_REQUIRED; + } else { + server->sec_mode &= + ~(SECMODE_SIGN_ENABLED | SECMODE_SIGN_REQUIRED); + } + } else { + cFYI(1, "Signing disabled"); + if (server->sec_mode & SMB2_NEGOTIATE_SIGNING_REQUIRED) { + cERROR(1, "Server requires packet signing to be enabled" + " in /proc/fs/cifs/SecurityFlags."); + rc = -EOPNOTSUPP; + goto neg_exit; + } + server->sec_mode &= + ~(SECMODE_SIGN_ENABLED | SECMODE_SIGN_REQUIRED); + } + #ifdef CONFIG_SMB2_ASN1 /* BB REMOVEME when updated asn1.c ready */ rc = decode_neg_token_init(security_blob, blob_length, &server->sec_type); @@ -669,6 +701,8 @@ SMB2_logoff(const unsigned int xid, struct cifs_ses *ses) /* since no tcon, smb2_init can not do this, so do here */ req->hdr.SessionId = ses->Suid; + if (server->sec_mode & SECMODE_SIGN_REQUIRED) + req->hdr.Flags |= SMB2_FLAGS_SIGNED; rc = SendReceiveNoRsp(xid, ses, (char *) &req->hdr, 0); /* @@ -1268,10 +1302,16 @@ smb2_readv_callback(struct mid_q_entry *mid) case MID_RESPONSE_RECEIVED: credits_received = le16_to_cpu(buf->CreditRequest); /* result already set, check signature */ - /* if (server->sec_mode & - (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) - if (smb2_verify_signature(mid->resp_buf, server)) - cERROR(1, "Unexpected SMB signature"); */ + if (server->sec_mode & + (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) { + int rc; + + rc = smb2_verify_signature2(rdata->iov, rdata->nr_iov, + server); + if (rc) + cERROR(1, "SMB signature verification returned " + "error = %d", rc); + } /* FIXME: should this be counted toward the initiating task? */ task_io_account_read(rdata->bytes); cifs_stats_bytes_read(tcon, rdata->bytes); diff --git a/fs/cifs/smb2proto.h b/fs/cifs/smb2proto.h index 192d0c7d91eb..dbbdc39fa209 100644 --- a/fs/cifs/smb2proto.h +++ b/fs/cifs/smb2proto.h @@ -39,6 +39,8 @@ extern char *smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr); extern __le16 *cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb); +extern int smb2_verify_signature2(struct kvec *, unsigned int, + struct TCP_Server_Info *); 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, diff --git a/fs/cifs/smb2transport.c b/fs/cifs/smb2transport.c index 31f5d420b3ea..66479f252ae5 100644 --- a/fs/cifs/smb2transport.c +++ b/fs/cifs/smb2transport.c @@ -36,6 +36,149 @@ #include "smb2proto.h" #include "cifs_debug.h" #include "smb2status.h" +#include "smb2glob.h" + +static int +smb2_calc_signature2(const struct kvec *iov, int n_vec, + struct TCP_Server_Info *server) +{ + int i, rc; + unsigned char smb2_signature[SMB2_HMACSHA256_SIZE]; + unsigned char *sigptr = smb2_signature; + struct smb2_hdr *smb2_pdu = (struct smb2_hdr *)iov[0].iov_base; + + memset(smb2_signature, 0x0, SMB2_HMACSHA256_SIZE); + memset(smb2_pdu->Signature, 0x0, SMB2_SIGNATURE_SIZE); + + rc = crypto_shash_setkey(server->secmech.hmacsha256, + server->session_key.response, SMB2_NTLMV2_SESSKEY_SIZE); + if (rc) { + cERROR(1, "%s: Could not update with response\n", __func__); + return rc; + } + + rc = crypto_shash_init(&server->secmech.sdeschmacsha256->shash); + if (rc) { + cERROR(1, "%s: Could not init md5\n", __func__); + return rc; + } + + for (i = 0; i < n_vec; i++) { + if (iov[i].iov_len == 0) + continue; + if (iov[i].iov_base == NULL) { + cERROR(1, "null iovec entry"); + return -EIO; + } + /* + * The first entry includes a length field (which does not get + * signed that occupies the first 4 bytes before the header). + */ + if (i == 0) { + if (iov[0].iov_len <= 8) /* cmd field at offset 9 */ + break; /* nothing to sign or corrupt header */ + rc = + crypto_shash_update( + &server->secmech.sdeschmacsha256->shash, + iov[i].iov_base + 4, iov[i].iov_len - 4); + } else { + rc = + crypto_shash_update( + &server->secmech.sdeschmacsha256->shash, + iov[i].iov_base, iov[i].iov_len); + } + if (rc) { + cERROR(1, "%s: Could not update with payload\n", + __func__); + return rc; + } + } + + rc = crypto_shash_final(&server->secmech.sdeschmacsha256->shash, + sigptr); + if (rc) + cERROR(1, "%s: Could not generate sha256 hash\n", __func__); + + memcpy(smb2_pdu->Signature, sigptr, SMB2_SIGNATURE_SIZE); + + return rc; +} + +/* must be called with server->srv_mutex held */ +static int +smb2_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server) +{ + int rc = 0; + struct smb2_hdr *smb2_pdu = iov[0].iov_base; + + if (!(smb2_pdu->Flags & SMB2_FLAGS_SIGNED) || + server->tcpStatus == CifsNeedNegotiate) + return rc; + + if (!server->session_estab) { + strncpy(smb2_pdu->Signature, "BSRSPYL", 8); + return rc; + } + + rc = smb2_calc_signature2(iov, n_vec, server); + + return rc; +} + +int +smb2_verify_signature2(struct kvec *iov, unsigned int n_vec, + struct TCP_Server_Info *server) +{ + unsigned int rc; + char server_response_sig[16]; + struct smb2_hdr *smb2_pdu = (struct smb2_hdr *)iov[0].iov_base; + + if ((smb2_pdu->Command == SMB2_NEGOTIATE) || + (smb2_pdu->Command == SMB2_OPLOCK_BREAK) || + (!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(smb2_pdu->Signature, "BSRSPYL ", 8) == 0) + cFYI(1, "dummy signature received for smb command 0x%x", + smb2_pdu->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, smb2_pdu->Signature, SMB2_SIGNATURE_SIZE); + + memset(smb2_pdu->Signature, 0, SMB2_SIGNATURE_SIZE); + + mutex_lock(&server->srv_mutex); + rc = smb2_calc_signature2(iov, n_vec, server); + mutex_unlock(&server->srv_mutex); + + if (rc) + return rc; + + if (memcmp(server_response_sig, smb2_pdu->Signature, + SMB2_SIGNATURE_SIZE)) + return -EACCES; + else + return 0; +} + +static int +smb2_verify_signature(struct smb2_hdr *smb2_pdu, struct TCP_Server_Info *server) +{ + struct kvec iov; + + iov.iov_base = (char *)smb2_pdu; + iov.iov_len = get_rfc1002_length(smb2_pdu) + 4; + return smb2_verify_signature2(&iov, 1, server); +} /* * Set message id for the request. Should be called after wait_for_free_request @@ -118,12 +261,15 @@ smb2_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server, dump_smb(mid->resp_buf, min_t(u32, 80, len)); /* convert the length into a more usable form */ - /* BB - uncomment with SMB2 signing implementation */ - /* if ((len > 24) && + if ((len > 24) && (server->sec_mode & (SECMODE_SIGN_REQUIRED|SECMODE_SIGN_ENABLED))) { - if (smb2_verify_signature(mid->resp_buf, server)) - cERROR(1, "Unexpected SMB signature"); - } */ + int rc; + + rc = smb2_verify_signature(mid->resp_buf, server); + if (rc) + cERROR(1, "SMB signature verification returned error = " + "%d", rc); + } return map_smb2_to_linux_error(mid->resp_buf, log_error); } @@ -141,9 +287,9 @@ smb2_setup_request(struct cifs_ses *ses, struct kvec *iov, rc = smb2_get_mid_entry(ses, hdr, &mid); if (rc) return rc; - /* rc = smb2_sign_smb2(iov, nvec, ses->server); + rc = smb2_sign_smb2(iov, nvec, ses->server); if (rc) - delete_mid(mid); */ + cifs_delete_mid(mid); *ret_mid = mid; return rc; } @@ -162,11 +308,12 @@ smb2_setup_async_request(struct TCP_Server_Info *server, struct kvec *iov, if (mid == NULL) return -ENOMEM; - /* rc = smb2_sign_smb2(iov, nvec, server); + rc = smb2_sign_smb2(iov, nvec, server); if (rc) { DeleteMidQEntry(mid); return rc; - }*/ + } + *ret_mid = mid; return rc; } diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c index d9b639b95fa8..c4d7825dfc0a 100644 --- a/fs/cifs/transport.c +++ b/fs/cifs/transport.c @@ -109,8 +109,8 @@ DeleteMidQEntry(struct mid_q_entry *midEntry) mempool_free(midEntry, cifs_mid_poolp); } -static void -delete_mid(struct mid_q_entry *mid) +void +cifs_delete_mid(struct mid_q_entry *mid) { spin_lock(&GlobalMid_Lock); list_del(&mid->qhead); @@ -419,7 +419,7 @@ cifs_call_async(struct TCP_Server_Info *server, struct kvec *iov, if (rc == 0) return 0; - delete_mid(mid); + cifs_delete_mid(mid); add_credits(server, 1, optype); wake_up(&server->request_q); return rc; @@ -532,7 +532,7 @@ cifs_setup_request(struct cifs_ses *ses, struct kvec *iov, return rc; rc = cifs_sign_smbv(iov, nvec, ses->server, &mid->sequence_number); if (rc) - delete_mid(mid); + cifs_delete_mid(mid); *ret_mid = mid; return rc; } @@ -652,11 +652,11 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses, rc = ses->server->ops->check_receive(midQ, ses->server, flags & CIFS_LOG_ERROR); - /* mark it so buf will not be freed by delete_mid */ + /* mark it so buf will not be freed by cifs_delete_mid */ if ((flags & CIFS_NO_RESP) == 0) midQ->resp_buf = NULL; out: - delete_mid(midQ); + cifs_delete_mid(midQ); add_credits(ses->server, credits, optype); return rc; @@ -762,7 +762,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses, memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4); rc = cifs_check_receive(midQ, ses->server, 0); out: - delete_mid(midQ); + cifs_delete_mid(midQ); add_credits(ses->server, 1, 0); return rc; @@ -846,7 +846,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon, rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number); if (rc) { - delete_mid(midQ); + cifs_delete_mid(midQ); mutex_unlock(&ses->server->srv_mutex); return rc; } @@ -859,7 +859,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon, mutex_unlock(&ses->server->srv_mutex); if (rc < 0) { - delete_mid(midQ); + cifs_delete_mid(midQ); return rc; } @@ -880,7 +880,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon, blocking lock to return. */ rc = send_cancel(ses->server, in_buf, midQ); if (rc) { - delete_mid(midQ); + cifs_delete_mid(midQ); return rc; } } else { @@ -892,7 +892,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon, /* If we get -ENOLCK back the lock may have already been removed. Don't exit in this case. */ if (rc && rc != -ENOLCK) { - delete_mid(midQ); + cifs_delete_mid(midQ); return rc; } } @@ -929,7 +929,7 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon, memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4); rc = cifs_check_receive(midQ, ses->server, 0); out: - delete_mid(midQ); + cifs_delete_mid(midQ); if (rstart && rc == -EACCES) return -ERESTARTSYS; return rc; |
