From patchwork Sun Sep 19 03:02:35 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shirish Pargaonkar X-Patchwork-Id: 193082 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id o8J36kGJ019169 for ; Sun, 19 Sep 2010 03:07:20 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754611Ab0ISDHU (ORCPT ); Sat, 18 Sep 2010 23:07:20 -0400 Received: from mail-vw0-f46.google.com ([209.85.212.46]:65018 "EHLO mail-vw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753343Ab0ISDHT (ORCPT ); Sat, 18 Sep 2010 23:07:19 -0400 Received: by mail-vw0-f46.google.com with SMTP id 3so2462371vws.19 for ; Sat, 18 Sep 2010 20:07:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:from:to:cc:subject:date :message-id:x-mailer; bh=e7DZXckYjdx4t+HYd51/ONlOlIH0a+h2UPz/PxVBURg=; b=Kkn+3FZkzER4O6Z0D20xuTckr69pX5V3Ep2ISqIkcEmIG1RdUoynCWV3Ff7seLVhNK bjldXAA8tmmHXBHm1A7dhjxGEM7IWH32tJXPZqIufRC+r38q9FUNbxps9P+16crCdbMr j7TKg0wg9WP79cGYTrw7sFf/7O/hEydTBrHzw= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer; b=xVuGuN6qR7bP6lHTED/btudLT/KWLgcmzl0w3/snSQPQ6tQ44eQG7MIX8cZ820k1Jh on5b4QavTkcTztxNT2Xe6nhUHXhmeHCaD5qzd4bnGYbR1hzDuAg0SX3A8rkvLSwZ3lDO NmBrI3upBQtDajlwLQ4KYNj6XATg+ZNvXQmbA= Received: by 10.220.33.202 with SMTP id i10mr3570678vcd.208.1284865638211; Sat, 18 Sep 2010 20:07:18 -0700 (PDT) Received: from localhost ([32.97.110.58]) by mx.google.com with ESMTPS id w31sm3524954vbs.5.2010.09.18.20.07.16 (version=TLSv1/SSLv3 cipher=RC4-MD5); Sat, 18 Sep 2010 20:07:17 -0700 (PDT) From: shirishpargaonkar@gmail.com To: smfrench@gmail.com Cc: linux-cifs@vger.kernel.org, Shirish Pargaonkar Subject: [PATCH -v6 3/4] cifs NTLMv2/NTLMSSP define crypto hash functions and create and send keys needed for key exchange Date: Sat, 18 Sep 2010 22:02:35 -0500 Message-Id: <1284865355-16815-1-git-send-email-shirishpargaonkar@gmail.com> X-Mailer: git-send-email 1.6.0.2 Sender: linux-cifs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter1.kernel.org [140.211.167.41]); Sun, 19 Sep 2010 03:07:20 +0000 (UTC) diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig index 917b7d4..0ed2139 100644 --- a/fs/cifs/Kconfig +++ b/fs/cifs/Kconfig @@ -2,6 +2,9 @@ config CIFS tristate "CIFS support (advanced network filesystem, SMBFS successor)" depends on INET select NLS + select CRYPTO + select CRYPTO_MD5 + select CRYPTO_ARC4 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 730038a..48026c6 100644 --- a/fs/cifs/cifsencrypt.c +++ b/fs/cifs/cifsencrypt.c @@ -477,3 +477,128 @@ void CalcNTLMv2_response(const struct cifsSesInfo *ses, hmac_md5_final(v2_session_response, &context); /* cifs_dump_mem("v2_sess_rsp: ", v2_session_response, 32); */ } + +int +calc_seckey(struct TCP_Server_Info *server) +{ + int rc; + struct crypto_blkcipher *tfm_arc4; + struct scatterlist sgin, sgout; + struct blkcipher_desc desc; + + if (!server) { + cERROR(1, "%s: Can't determine ciphertext key\n", __func__); + return 1; + } + + mutex_lock(&server->srv_mutex); + if (server->cphready) { + mutex_unlock(&server->srv_mutex); + return 0; + } + + get_random_bytes(server->ntlmssp.sec_key, CIFS_NTLMV2_SESSKEY_SIZE); + + tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", + 0, CRYPTO_ALG_ASYNC); + if (!tfm_arc4 || IS_ERR(tfm_arc4)) { + cERROR(1, "could not allocate crypto API arc4\n"); + mutex_unlock(&server->srv_mutex); + return PTR_ERR(tfm_arc4); + } + + desc.tfm = tfm_arc4; + + crypto_blkcipher_setkey(tfm_arc4, server->session_key.data.ntlmv2.key, + CIFS_CPHTXT_SIZE); + + sg_init_one(&sgin, server->ntlmssp.sec_key, CIFS_CPHTXT_SIZE); + sg_init_one(&sgout, server->ntlmssp.ciphertext, CIFS_CPHTXT_SIZE); + + rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, CIFS_CPHTXT_SIZE); + if (rc) { + cERROR(1, "could not encrypt session key rc: %d\n", rc); + crypto_free_blkcipher(tfm_arc4); + mutex_unlock(&server->srv_mutex); + return rc; + } + + crypto_free_blkcipher(tfm_arc4); + + server->sequence_number = 0; + server->cphready = true; + mutex_unlock(&server->srv_mutex); + + return 0; +} + +void +cifs_crypto_shash_release(struct TCP_Server_Info *server) +{ + if (server->secmech.md5) + crypto_free_shash(server->secmech.md5); + + if (server->secmech.hmacmd5) + crypto_free_shash(server->secmech.hmacmd5); + + kfree(server->secmech.sdeschmacmd5); + + kfree(server->secmech.sdescmd5); +} + +int +cifs_crypto_shash_allocate(struct TCP_Server_Info *server) +{ + int rc; + unsigned int size; + + server->secmech.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0); + if (!server->secmech.hmacmd5 || + IS_ERR(server->secmech.hmacmd5)) { + cERROR(1, "could not allocate crypto hmacmd5\n"); + return PTR_ERR(server->secmech.hmacmd5); + } + + server->secmech.md5 = crypto_alloc_shash("md5", 0, 0); + if (!server->secmech.md5 || IS_ERR(server->secmech.md5)) { + cERROR(1, "could not allocate crypto md5\n"); + rc = PTR_ERR(server->secmech.md5); + goto crypto_allocate_md5_fail; + } + + size = sizeof(struct shash_desc) + + crypto_shash_descsize(server->secmech.hmacmd5); + server->secmech.sdeschmacmd5 = kmalloc(size, GFP_KERNEL); + if (!server->secmech.sdeschmacmd5) { + cERROR(1, "cifs_crypto_shash_allocate: can't alloc hmacmd5\n"); + rc = -ENOMEM; + goto crypto_allocate_hmacmd5_sdesc_fail; + } + 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); + if (!server->secmech.sdescmd5) { + cERROR(1, "cifs_crypto_shash_allocate: can't alloc md5\n"); + rc = -ENOMEM; + goto crypto_allocate_md5_sdesc_fail; + } + server->secmech.sdescmd5->shash.tfm = server->secmech.md5; + server->secmech.sdescmd5->shash.flags = 0x0; + + return 0; + +crypto_allocate_md5_sdesc_fail: + kfree(server->secmech.sdeschmacmd5); + +crypto_allocate_hmacmd5_sdesc_fail: + crypto_free_shash(server->secmech.md5); + +crypto_allocate_md5_fail: + crypto_free_shash(server->secmech.hmacmd5); + + return rc; +} diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index c68f31c..c7da866 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -25,6 +25,9 @@ #include #include "cifs_fs_sb.h" #include "cifsacl.h" +#include +#include + /* * The sizes of various internal tables and strings */ @@ -109,6 +112,28 @@ struct session_key { } data; }; +/* crypto security descriptor definition */ +struct sdesc { + struct shash_desc shash; + char ctx[]; +}; + +/* crypto hashing related structure/fields, not speicific to a sec mech */ +struct cifs_secmech { + struct crypto_shash *hmacmd5; /* hmac-md5 hash function */ + struct crypto_shash *md5; /* md5 hash function */ + struct sdesc *sdeschmacmd5; /* ctxt to generate ntlmv2 hash, CR1 */ + struct sdesc *sdescmd5; /* ctxt to generate cifs/smb signature */ +}; + +/* per smb connection structure/fields */ +struct ntlmssp_auth { + __u32 client_flags; /* sent by client in type 1 ntlmsssp exchange */ + __u32 server_flags; /* sent by server in type 2 ntlmssp exchange */ + unsigned char sec_key[CIFS_CPHTXT_SIZE]; /* a nonce client generates */ + unsigned char ciphertext[CIFS_CPHTXT_SIZE]; /* sent to server */ +}; + struct cifs_cred { int uid; int gid; @@ -187,6 +212,9 @@ struct TCP_Server_Info { unsigned long lstrp; /* when we got last response from this server */ u16 dialect; /* dialect index that server chose */ /* extended security flavors that server supports */ + struct cifs_secmech secmech; /* crypto sec mech functs, descriptors */ + struct ntlmssp_auth ntlmssp; /* sec key, ciphertext, flags */ + bool cphready; /* ciphertext is calculated */ bool sec_kerberos; /* supports plain Kerberos */ bool sec_mskerberos; /* supports legacy MS Kerberos */ bool sec_kerberosu2u; /* supports U2U Kerberos */ diff --git a/fs/cifs/cifspdu.h b/fs/cifs/cifspdu.h index b0f4b56..dc90a36 100644 --- a/fs/cifs/cifspdu.h +++ b/fs/cifs/cifspdu.h @@ -134,6 +134,13 @@ * Size of the session key (crypto key encrypted with the password */ #define CIFS_SESS_KEY_SIZE (24) +#define CIFS_CLIENT_CHALLENGE_SIZE (8) +#define CIFS_SERVER_CHALLENGE_SIZE (8) +#define CIFS_HMAC_MD5_HASH_SIZE (16) +#define CIFS_CPHTXT_SIZE (16) +#define CIFS_NTLMV2_SESSKEY_SIZE (16) +#define CIFS_NTHASH_SIZE (16) + /* * Maximum user name length diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h index c155479..d89a87a 100644 --- a/fs/cifs/cifsproto.h +++ b/fs/cifs/cifsproto.h @@ -369,6 +369,9 @@ extern int cifs_calculate_session_key(struct session_key *key, const char *rn, extern void CalcNTLMv2_response(const struct cifsSesInfo *, char *); extern int setup_ntlmv2_rsp(struct cifsSesInfo *, char *, const struct nls_table *); +extern int cifs_crypto_shash_allocate(struct TCP_Server_Info *); +extern void cifs_crypto_shash_release(struct TCP_Server_Info *); +extern int calc_seckey(struct TCP_Server_Info *); #ifdef CONFIG_CIFS_WEAK_PW_HASH extern void calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt, char *lnm_session_key); diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index c99760a..4818089 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -199,6 +199,7 @@ cifs_reconnect(struct TCP_Server_Info *server) if (server->tcpStatus != CifsExiting) server->tcpStatus = CifsGood; server->sequence_number = 0; + server->cphready = false; spin_unlock(&GlobalMid_Lock); /* atomic_set(&server->inFlight,0);*/ wake_up(&server->response_q); @@ -1502,6 +1503,7 @@ cifs_put_tcp_session(struct TCP_Server_Info *server) server->tcpStatus = CifsExiting; spin_unlock(&GlobalMid_Lock); + cifs_crypto_shash_release(server); cifs_fscache_release_client_cookie(server); task = xchg(&server->tsk, NULL); @@ -1556,12 +1558,19 @@ cifs_get_tcp_session(struct smb_vol *volume_info) goto out_err; } + rc = cifs_crypto_shash_allocate(tcp_ses); + if (rc) { + cERROR(1, "could not setup hash structures rc %d", rc); + goto out_err; + } + tcp_ses->hostname = extract_hostname(volume_info->UNC); if (IS_ERR(tcp_ses->hostname)) { rc = PTR_ERR(tcp_ses->hostname); - goto out_err; + goto out_err2; } + tcp_ses->cphready = false; tcp_ses->noblocksnd = volume_info->noblocksnd; tcp_ses->noautotune = volume_info->noautotune; tcp_ses->tcp_nodelay = volume_info->sockopt_tcp_nodelay; @@ -1600,7 +1609,7 @@ cifs_get_tcp_session(struct smb_vol *volume_info) } if (rc < 0) { cERROR(1, "Error connecting to socket. Aborting operation"); - goto out_err; + goto out_err2; } /* @@ -1614,7 +1623,7 @@ cifs_get_tcp_session(struct smb_vol *volume_info) rc = PTR_ERR(tcp_ses->tsk); cERROR(1, "error %d create cifsd thread", rc); module_put(THIS_MODULE); - goto out_err; + goto out_err2; } /* thread spawned, put it on the list */ @@ -1626,6 +1635,9 @@ cifs_get_tcp_session(struct smb_vol *volume_info) return tcp_ses; +out_err2: + cifs_crypto_shash_release(tcp_ses); + out_err: if (tcp_ses) { if (!IS_ERR(tcp_ses->hostname)) diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c index af18a50..45555de 100644 --- a/fs/cifs/sess.c +++ b/fs/cifs/sess.c @@ -407,7 +407,7 @@ static int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len, /* In particular we can examine sign flags */ /* BB spec says that if AvId field of MsvAvTimestamp is populated then we must set the MIC field of the AUTHENTICATE_MESSAGE */ - + ses->server->ntlmssp.server_flags = le32_to_cpu(pblob->NegotiateFlags); tioffset = cpu_to_le16(pblob->TargetInfoArray.BufferOffset); tilen = cpu_to_le16(pblob->TargetInfoArray.Length); ses->tilen = tilen; @@ -443,10 +443,12 @@ static void build_ntlmssp_negotiate_blob(unsigned char *pbuffer, NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE | NTLMSSP_NEGOTIATE_NTLM; if (ses->server->secMode & - (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) + (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) { flags |= NTLMSSP_NEGOTIATE_SIGN; - if (ses->server->secMode & SECMODE_SIGN_REQUIRED) - flags |= NTLMSSP_NEGOTIATE_ALWAYS_SIGN; + if (!ses->server->cphready) + flags |= NTLMSSP_NEGOTIATE_KEY_XCH | + NTLMSSP_NEGOTIATE_EXTENDED_SEC; + } sec_blob->NegotiateFlags |= cpu_to_le32(flags); @@ -553,9 +555,19 @@ static int build_ntlmssp_auth_blob(unsigned char *pbuffer, sec_blob->WorkstationName.MaximumLength = 0; tmp += 2; - sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - pbuffer); - sec_blob->SessionKey.Length = 0; - sec_blob->SessionKey.MaximumLength = 0; + if ((ses->server->ntlmssp.server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) && + !calc_seckey(ses->server)) { + memcpy(tmp, ses->server->ntlmssp.ciphertext, CIFS_CPHTXT_SIZE); + sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - pbuffer); + sec_blob->SessionKey.Length = cpu_to_le16(CIFS_CPHTXT_SIZE); + sec_blob->SessionKey.MaximumLength = + cpu_to_le16(CIFS_CPHTXT_SIZE); + tmp += CIFS_CPHTXT_SIZE; + } else { + sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - pbuffer); + sec_blob->SessionKey.Length = 0; + sec_blob->SessionKey.MaximumLength = 0; + } setup_ntlmv2_ret: return tmp - pbuffer;