From patchwork Tue Oct 12 19:45:35 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shirish Pargaonkar X-Patchwork-Id: 248971 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 o9CJnvww024407 for ; Tue, 12 Oct 2010 19:50:28 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754772Ab0JLTu2 (ORCPT ); Tue, 12 Oct 2010 15:50:28 -0400 Received: from mail-iw0-f174.google.com ([209.85.214.174]:35347 "EHLO mail-iw0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754251Ab0JLTu1 (ORCPT ); Tue, 12 Oct 2010 15:50:27 -0400 Received: by mail-iw0-f174.google.com with SMTP id 7so1136626iwn.19 for ; Tue, 12 Oct 2010 12:50:27 -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=u1n9A/vEHtkG7labeVoZbSIGpQt+OhFU0cnZQ+u0jwU=; 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Tue, 12 Oct 2010 19:50:28 +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 83a17d7..53ebaf8 100644 --- a/fs/cifs/cifsencrypt.c +++ b/fs/cifs/cifsencrypt.c @@ -532,3 +532,114 @@ 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 cifsSesInfo *ses) +{ + int rc; + struct crypto_blkcipher *tfm_arc4; + struct scatterlist sgin, sgout; + struct blkcipher_desc desc; + unsigned char sec_key[CIFS_NTLMV2_SESSKEY_SIZE]; /* a nonce */ + + get_random_bytes(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"); + return PTR_ERR(tfm_arc4); + } + + desc.tfm = tfm_arc4; + + crypto_blkcipher_setkey(tfm_arc4, ses->auth_key.data.ntlmv2.key, + CIFS_NTLMV2_SESSKEY_SIZE); + + sg_init_one(&sgin, sec_key, CIFS_NTLMV2_SESSKEY_SIZE); + sg_init_one(&sgout, ses->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); + return rc; + } + + /* make secondary_key/nonce as session key */ + memcpy(&ses->auth_key.data, sec_key, CIFS_NTLMV2_SESSKEY_SIZE); + + crypto_free_blkcipher(tfm_arc4); + + 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 5dd5659..d00499e 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 */ @@ -110,6 +113,27 @@ 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 ciphertext[CIFS_CPHTXT_SIZE]; /* sent to server */ +}; + struct cifs_cred { int uid; int gid; @@ -186,6 +210,7 @@ struct TCP_Server_Info { struct session_key session_key; unsigned long lstrp; /* when we got last response from this server */ u16 dialect; /* dialect index that server chose */ + struct cifs_secmech secmech; /* crypto sec mech functs, descriptors */ /* extended security flavors that server supports */ bool sec_kerberos; /* supports plain Kerberos */ bool sec_mskerberos; /* supports legacy MS Kerberos */ @@ -227,6 +252,7 @@ struct cifsSesInfo { struct session_key auth_key; char ntlmv2_hash[16]; unsigned int tilen; /* length of the target info blob */ + struct ntlmssp_auth ntlmssp; /* ciphertext, flags */ bool need_reconnect:1; /* connection reset, uid now invalid */ }; /* no more than one of the following three session flags may be set */ diff --git a/fs/cifs/cifspdu.h b/fs/cifs/cifspdu.h index e778165..54e1628 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) + /* * Max expected size of an av pair blob in ntlmv2 auth exchange diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h index 29a2ee8..dae3402 100644 --- a/fs/cifs/cifsproto.h +++ b/fs/cifs/cifsproto.h @@ -370,6 +370,9 @@ 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 cifsSesInfo *); #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 ca207e8..848e458 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -1560,6 +1560,7 @@ 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); @@ -1614,10 +1615,16 @@ 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->noblocksnd = volume_info->noblocksnd; @@ -1661,7 +1668,7 @@ 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; } /* @@ -1675,7 +1682,7 @@ 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 */ @@ -1687,6 +1694,9 @@ 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 28aedae..e755803 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->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; @@ -437,10 +437,12 @@ 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->session_estab) + flags |= NTLMSSP_NEGOTIATE_KEY_XCH | + NTLMSSP_NEGOTIATE_EXTENDED_SEC; + } sec_blob->NegotiateFlags |= cpu_to_le32(flags); @@ -544,9 +546,19 @@ 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->ntlmssp.server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) && + !calc_seckey(ses)) { + memcpy(tmp, ses->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;