[CIFS] Fix ntlmv2 auth with ntlmssp

Make ntlmv2 as an authentication mechanism within ntlmssp
instead of ntlmv1.
Parse type 2 response in ntlmssp negotiation to pluck
AV pairs and use them to calculate ntlmv2 response token.
Also, assign domain name from the sever response in type 2
packet of ntlmssp and use that (netbios) domain name in
calculation of response.

Enable cifs/smb signing using rc4 and md5.

Changed name of the structure mac_key to session_key to reflect
the type of key it holds.

Use kernel crypto_shash_* APIs instead of the equivalent cifs functions.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 294 insertions, 122 deletions

diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
index 847628dfdc44..051d00011ca3 100644
--- a/fs/cifs/cifsencrypt.c
+++ b/fs/cifs/cifsencrypt.c
@@ -27,6 +27,7 @@
 #include "md5.h"
 #include "cifs_unicode.h"
 #include "cifsproto.h"
+#include "ntlmssp.h"
 #include <linux/ctype.h>
 #include <linux/random.h>
 
@@ -42,21 +43,44 @@ extern void SMBencrypt(unsigned char *passwd, const unsigned char *c8,
 		       unsigned char *p24);
 
 static int cifs_calculate_signature(const struct smb_hdr *cifs_pdu,
-				    const struct mac_key *key, char *signature)
+			struct TCP_Server_Info *server, char *signature)
 {
-	struct	MD5Context context;
+	int rc = 0;
+	struct {
+		struct shash_desc shash;
+		char ctx[crypto_shash_descsize(server->ntlmssp.md5)];
+	} sdesc;
 
-	if ((cifs_pdu == NULL) || (signature == NULL) || (key == NULL))
+	if (cifs_pdu == NULL || server == NULL || signature == NULL)
 		return -EINVAL;
 
-	cifs_MD5_init(&context);
-	cifs_MD5_update(&context, (char *)&key->data, key->len);
-	cifs_MD5_update(&context, cifs_pdu->Protocol, cifs_pdu->smb_buf_length);
+	sdesc.shash.tfm = server->ntlmssp.md5;
+	sdesc.shash.flags = 0x0;
+
+	rc = crypto_shash_init(&sdesc.shash);
+	if (rc) {
+		cERROR(1, "could not initialize master crypto API hmacmd5\n");
+		return rc;
+	}
+
+	if (server->secType == RawNTLMSSP)
+		crypto_shash_update(&sdesc.shash,
+			server->session_key.data.ntlmv2.key,
+			CIFS_NTLMV2_SESSKEY_SIZE);
+	else
+		crypto_shash_update(&sdesc.shash,
+			(char *)&server->session_key.data,
+			server->session_key.len);
+
+	crypto_shash_update(&sdesc.shash,
+			cifs_pdu->Protocol, cifs_pdu->smb_buf_length);
+
+	rc = crypto_shash_final(&sdesc.shash, signature);
 
-	cifs_MD5_final(signature, &context);
 	return 0;
 }
 
+
 int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
 		  __u32 *pexpected_response_sequence_number)
 {
@@ -78,8 +102,7 @@ int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
 	server->sequence_number++;
 	spin_unlock(&GlobalMid_Lock);
 
-	rc = cifs_calculate_signature(cifs_pdu, &server->mac_signing_key,
-				      smb_signature);
+	rc = cifs_calculate_signature(cifs_pdu, server, smb_signature);
 	if (rc)
 		memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
 	else
@@ -89,16 +112,36 @@ int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
 }
 
 static int cifs_calc_signature2(const struct kvec *iov, int n_vec,
-				const struct mac_key *key, char *signature)
+			struct TCP_Server_Info *server, char *signature)
 {
-	struct  MD5Context context;
 	int i;
+	int rc = 0;
+	struct {
+		struct shash_desc shash;
+		char ctx[crypto_shash_descsize(server->ntlmssp.md5)];
+	} sdesc;
 
-	if ((iov == NULL) || (signature == NULL) || (key == NULL))
+	if (iov == NULL || server == NULL || signature == NULL)
 		return -EINVAL;
 
-	cifs_MD5_init(&context);
-	cifs_MD5_update(&context, (char *)&key->data, key->len);
+	sdesc.shash.tfm = server->ntlmssp.md5;
+	sdesc.shash.flags = 0x0;
+
+	rc = crypto_shash_init(&sdesc.shash);
+	if (rc) {
+		cERROR(1, "could not initialize master crypto API hmacmd5\n");
+		return rc;
+	}
+
+	if (server->secType == RawNTLMSSP)
+		crypto_shash_update(&sdesc.shash,
+			server->session_key.data.ntlmv2.key,
+			CIFS_NTLMV2_SESSKEY_SIZE);
+	else
+		crypto_shash_update(&sdesc.shash,
+			(char *)&server->session_key.data,
+			server->session_key.len);
+
 	for (i = 0; i < n_vec; i++) {
 		if (iov[i].iov_len == 0)
 			continue;
@@ -111,18 +154,18 @@ static int cifs_calc_signature2(const struct kvec *iov, int n_vec,
 		if (i == 0) {
 			if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
 				break; /* nothing to sign or corrupt header */
-			cifs_MD5_update(&context, iov[0].iov_base+4,
-				  iov[0].iov_len-4);
+			crypto_shash_update(&sdesc.shash,
+				iov[i].iov_base + 4, iov[i].iov_len - 4);
 		} else
-			cifs_MD5_update(&context, iov[i].iov_base, iov[i].iov_len);
+			crypto_shash_update(&sdesc.shash,
+				iov[i].iov_base, iov[i].iov_len);
 	}
 
-	cifs_MD5_final(signature, &context);
+	rc = crypto_shash_final(&sdesc.shash, signature);
 
 	return 0;
 }
 
-
 int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
 		   __u32 *pexpected_response_sequence_number)
 {
@@ -145,8 +188,7 @@ int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
 	server->sequence_number++;
 	spin_unlock(&GlobalMid_Lock);
 
-	rc = cifs_calc_signature2(iov, n_vec, &server->mac_signing_key,
-				      smb_signature);
+	rc = cifs_calc_signature2(iov, n_vec, server, smb_signature);
 	if (rc)
 		memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
 	else
@@ -156,14 +198,14 @@ int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
 }
 
 int cifs_verify_signature(struct smb_hdr *cifs_pdu,
-			  const struct mac_key *mac_key,
+			  struct TCP_Server_Info *server,
 			  __u32 expected_sequence_number)
 {
-	unsigned int rc;
+	int rc;
 	char server_response_sig[8];
 	char what_we_think_sig_should_be[20];
 
-	if ((cifs_pdu == NULL) || (mac_key == NULL))
+	if (cifs_pdu == NULL || server == NULL)
 		return -EINVAL;
 
 	if (cifs_pdu->Command == SMB_COM_NEGOTIATE)
@@ -192,7 +234,7 @@ int cifs_verify_signature(struct smb_hdr *cifs_pdu,
 					cpu_to_le32(expected_sequence_number);
 	cifs_pdu->Signature.Sequence.Reserved = 0;
 
-	rc = cifs_calculate_signature(cifs_pdu, mac_key,
+	rc = cifs_calculate_signature(cifs_pdu, server,
 		what_we_think_sig_should_be);
 
 	if (rc)
@@ -209,7 +251,7 @@ int cifs_verify_signature(struct smb_hdr *cifs_pdu,
 }
 
 /* We fill in key by putting in 40 byte array which was allocated by caller */
-int cifs_calculate_mac_key(struct mac_key *key, const char *rn,
+int cifs_calculate_session_key(struct session_key *key, const char *rn,
 			   const char *password)
 {
 	char temp_key[16];
@@ -223,63 +265,6 @@ int cifs_calculate_mac_key(struct mac_key *key, const char *rn,
 	return 0;
 }
 
-int CalcNTLMv2_partial_mac_key(struct cifsSesInfo *ses,
-			       const struct nls_table *nls_info)
-{
-	char temp_hash[16];
-	struct HMACMD5Context ctx;
-	char *ucase_buf;
-	__le16 *unicode_buf;
-	unsigned int i, user_name_len, dom_name_len;
-
-	if (ses == NULL)
-		return -EINVAL;
-
-	E_md4hash(ses->password, temp_hash);
-
-	hmac_md5_init_limK_to_64(temp_hash, 16, &ctx);
-	user_name_len = strlen(ses->userName);
-	if (user_name_len > MAX_USERNAME_SIZE)
-		return -EINVAL;
-	if (ses->domainName == NULL)
-		return -EINVAL; /* BB should we use CIFS_LINUX_DOM */
-	dom_name_len = strlen(ses->domainName);
-	if (dom_name_len > MAX_USERNAME_SIZE)
-		return -EINVAL;
-
-	ucase_buf = kmalloc((MAX_USERNAME_SIZE+1), GFP_KERNEL);
-	if (ucase_buf == NULL)
-		return -ENOMEM;
-	unicode_buf = kmalloc((MAX_USERNAME_SIZE+1)*4, GFP_KERNEL);
-	if (unicode_buf == NULL) {
-		kfree(ucase_buf);
-		return -ENOMEM;
-	}
-
-	for (i = 0; i < user_name_len; i++)
-		ucase_buf[i] = nls_info->charset2upper[(int)ses->userName[i]];
-	ucase_buf[i] = 0;
-	user_name_len = cifs_strtoUCS(unicode_buf, ucase_buf,
-				      MAX_USERNAME_SIZE*2, nls_info);
-	unicode_buf[user_name_len] = 0;
-	user_name_len++;
-
-	for (i = 0; i < dom_name_len; i++)
-		ucase_buf[i] = nls_info->charset2upper[(int)ses->domainName[i]];
-	ucase_buf[i] = 0;
-	dom_name_len = cifs_strtoUCS(unicode_buf+user_name_len, ucase_buf,
-				     MAX_USERNAME_SIZE*2, nls_info);
-
-	unicode_buf[user_name_len + dom_name_len] = 0;
-	hmac_md5_update((const unsigned char *) unicode_buf,
-		(user_name_len+dom_name_len)*2, &ctx);
-
-	hmac_md5_final(ses->server->ntlmv2_hash, &ctx);
-	kfree(ucase_buf);
-	kfree(unicode_buf);
-	return 0;
-}
-
 #ifdef CONFIG_CIFS_WEAK_PW_HASH
 void calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt,
 			char *lnm_session_key)
@@ -324,21 +309,29 @@ static int calc_ntlmv2_hash(struct cifsSesInfo *ses,
 {
 	int rc = 0;
 	int len;
-	char nt_hash[16];
-	struct HMACMD5Context *pctxt;
+	char nt_hash[CIFS_NTHASH_SIZE];
 	wchar_t *user;
 	wchar_t *domain;
-
-	pctxt = kmalloc(sizeof(struct HMACMD5Context), GFP_KERNEL);
-
-	if (pctxt == NULL)
-		return -ENOMEM;
+	wchar_t *server;
+	struct {
+		struct shash_desc shash;
+		char ctx[crypto_shash_descsize(ses->server->ntlmssp.hmacmd5)];
+	} sdesc;
 
 	/* calculate md4 hash of password */
 	E_md4hash(ses->password, nt_hash);
 
-	/* convert Domainname to unicode and uppercase */
-	hmac_md5_init_limK_to_64(nt_hash, 16, pctxt);
+	sdesc.shash.tfm = ses->server->ntlmssp.hmacmd5;
+	sdesc.shash.flags = 0x0;
+
+	crypto_shash_setkey(ses->server->ntlmssp.hmacmd5, nt_hash,
+				CIFS_NTHASH_SIZE);
+
+	rc = crypto_shash_init(&sdesc.shash);
+	if (rc) {
+		cERROR(1, "could not initialize master crypto API hmacmd5\n");
+		return rc;
+	}
 
 	/* convert ses->userName to unicode and uppercase */
 	len = strlen(ses->userName);
@@ -347,7 +340,8 @@ static int calc_ntlmv2_hash(struct cifsSesInfo *ses,
 		goto calc_exit_2;
 	len = cifs_strtoUCS((__le16 *)user, ses->userName, len, nls_cp);
 	UniStrupr(user);
-	hmac_md5_update((char *)user, 2*len, pctxt);
+
+	crypto_shash_update(&sdesc.shash, (char *)user, 2 * len);
 
 	/* convert ses->domainName to unicode and uppercase */
 	if (ses->domainName) {
@@ -363,65 +357,243 @@ static int calc_ntlmv2_hash(struct cifsSesInfo *ses,
 		   Maybe converting the domain name earlier makes sense */
 		/* UniStrupr(domain); */
 
-		hmac_md5_update((char *)domain, 2*len, pctxt);
+		crypto_shash_update(&sdesc.shash, (char *)domain, 2 * len);
 
 		kfree(domain);
+	} else if (ses->serverName) {
+		len = strlen(ses->serverName);
+
+		server = kmalloc(2 + (len * 2), GFP_KERNEL);
+		if (server == NULL)
+			goto calc_exit_1;
+		len = cifs_strtoUCS((__le16 *)server, ses->serverName, len,
+					nls_cp);
+		/* the following line was removed since it didn't work well
+		   with lower cased domain name that passed as an option.
+		   Maybe converting the domain name earlier makes sense */
+		/* UniStrupr(domain); */
+
+		crypto_shash_update(&sdesc.shash, (char *)server, 2 * len);
+
+		kfree(server);
 	}
 calc_exit_1:
 	kfree(user);
 calc_exit_2:
 	/* BB FIXME what about bytes 24 through 40 of the signing key?
 	   compare with the NTLM example */
-	hmac_md5_final(ses->server->ntlmv2_hash, pctxt);
+	rc = crypto_shash_final(&sdesc.shash, ses->server->ntlmv2_hash);
 
-	kfree(pctxt);
 	return rc;
 }
 
-void setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf,
-		      const struct nls_table *nls_cp)
+static int
+find_domain_name(struct cifsSesInfo *ses)
+{
+	int rc = 0;
+	unsigned int attrsize;
+	unsigned int type;
+	unsigned char *blobptr;
+	struct ntlmssp2_name *attrptr;
+
+	if (ses->server->tiblob) {
+		blobptr = ses->server->tiblob;
+		attrptr = (struct ntlmssp2_name *) blobptr;
+
+		while ((type = attrptr->type) != 0) {
+			blobptr += 2; /* advance attr type */
+			attrsize = attrptr->length;
+			blobptr += 2; /* advance attr size */
+			if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
+				if (!ses->domainName) {
+					ses->domainName =
+						kmalloc(attrptr->length + 1,
+								GFP_KERNEL);
+					if (!ses->domainName)
+							return -ENOMEM;
+					cifs_from_ucs2(ses->domainName,
+						(__le16 *)blobptr,
+						attrptr->length,
+						attrptr->length,
+						load_nls_default(), false);
+				}
+			}
+			blobptr += attrsize; /* advance attr  value */
+			attrptr = (struct ntlmssp2_name *) blobptr;
+		}
+	} else {
+		ses->server->tilen = 2 * sizeof(struct ntlmssp2_name);
+		ses->server->tiblob = kmalloc(ses->server->tilen, GFP_KERNEL);
+		if (!ses->server->tiblob) {
+			ses->server->tilen = 0;
+			cERROR(1, "Challenge target info allocation failure");
+			return -ENOMEM;
+		}
+		memset(ses->server->tiblob, 0x0, ses->server->tilen);
+		attrptr = (struct ntlmssp2_name *) ses->server->tiblob;
+		attrptr->type = cpu_to_le16(NTLMSSP_DOMAIN_TYPE);
+	}
+
+	return rc;
+}
+
+static int
+CalcNTLMv2_response(const struct TCP_Server_Info *server,
+			 char *v2_session_response)
 {
 	int rc;
+	struct {
+		struct shash_desc shash;
+		char ctx[crypto_shash_descsize(server->ntlmssp.hmacmd5)];
+	} sdesc;
+
+	sdesc.shash.tfm = server->ntlmssp.hmacmd5;
+	sdesc.shash.flags = 0x0;
+
+	crypto_shash_setkey(server->ntlmssp.hmacmd5, server->ntlmv2_hash,
+		CIFS_HMAC_MD5_HASH_SIZE);
+
+	rc = crypto_shash_init(&sdesc.shash);
+	if (rc) {
+		cERROR(1, "could not initialize master crypto API hmacmd5\n");
+		return rc;
+	}
+
+	memcpy(v2_session_response + CIFS_SERVER_CHALLENGE_SIZE,
+		server->cryptKey, CIFS_SERVER_CHALLENGE_SIZE);
+	crypto_shash_update(&sdesc.shash,
+		v2_session_response + CIFS_SERVER_CHALLENGE_SIZE,
+		sizeof(struct ntlmv2_resp) - CIFS_SERVER_CHALLENGE_SIZE);
+
+	if (server->tilen)
+		crypto_shash_update(&sdesc.shash,
+					server->tiblob, server->tilen);
+
+	rc = crypto_shash_final(&sdesc.shash, v2_session_response);
+
+	return rc;
+}
+
+int
+setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf,
+		      const struct nls_table *nls_cp)
+{
+	int rc = 0;
 	struct ntlmv2_resp *buf = (struct ntlmv2_resp *)resp_buf;
-	struct HMACMD5Context context;
+	struct {
+		struct shash_desc shash;
+		char ctx[crypto_shash_descsize(ses->server->ntlmssp.hmacmd5)];
+	} sdesc;
 
 	buf->blob_signature = cpu_to_le32(0x00000101);
 	buf->reserved = 0;
 	buf->time = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
 	get_random_bytes(&buf->client_chal, sizeof(buf->client_chal));
 	buf->reserved2 = 0;
-	buf->names[0].type = cpu_to_le16(NTLMSSP_DOMAIN_TYPE);
-	buf->names[0].length = 0;
-	buf->names[1].type = 0;
-	buf->names[1].length = 0;
+
+	if (!ses->domainName) {
+		rc = find_domain_name(ses);
+		if (rc) {
+			cERROR(1, "could not get domain/server name rc %d", rc);
+			return rc;
+		}
+	}
 
 	/* calculate buf->ntlmv2_hash */
 	rc = calc_ntlmv2_hash(ses, nls_cp);
-	if (rc)
+	if (rc) {
+		cERROR(1, "could not get v2 hash rc %d", rc);
+		return rc;
+	}
+	rc = CalcNTLMv2_response(ses->server, resp_buf);
+	if (rc) {
 		cERROR(1, "could not get v2 hash rc %d", rc);
-	CalcNTLMv2_response(ses, resp_buf);
+		return rc;
+	}
+
+	crypto_shash_setkey(ses->server->ntlmssp.hmacmd5,
+			ses->server->ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
+
+	sdesc.shash.tfm = ses->server->ntlmssp.hmacmd5;
+	sdesc.shash.flags = 0x0;
+
+	rc = crypto_shash_init(&sdesc.shash);
+	if (rc) {
+		cERROR(1, "could not initialize master crypto API hmacmd5\n");
+		return rc;
+	}
+
+	crypto_shash_update(&sdesc.shash, resp_buf, CIFS_HMAC_MD5_HASH_SIZE);
 
-	/* now calculate the MAC key for NTLMv2 */
-	hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash, 16, &context);
-	hmac_md5_update(resp_buf, 16, &context);
-	hmac_md5_final(ses->server->mac_signing_key.data.ntlmv2.key, &context);
+	rc = crypto_shash_final(&sdesc.shash,
+		ses->server->session_key.data.ntlmv2.key);
 
-	memcpy(&ses->server->mac_signing_key.data.ntlmv2.resp, resp_buf,
-	       sizeof(struct ntlmv2_resp));
-	ses->server->mac_signing_key.len = 16 + sizeof(struct ntlmv2_resp);
+	memcpy(&ses->server->session_key.data.ntlmv2.resp, resp_buf,
+			sizeof(struct ntlmv2_resp));
+	ses->server->session_key.len = 16 + sizeof(struct ntlmv2_resp);
+
+	return rc;
 }
 
-void CalcNTLMv2_response(const struct cifsSesInfo *ses,
-			 char *v2_session_response)
+int
+calc_seckey(struct TCP_Server_Info *server)
 {
-	struct HMACMD5Context context;
-	/* rest of v2 struct already generated */
-	memcpy(v2_session_response + 8, ses->server->cryptKey, 8);
-	hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash, 16, &context);
+	int rc;
+	unsigned char sec_key[CIFS_NTLMV2_SESSKEY_SIZE];
+	struct crypto_blkcipher *tfm_arc4;
+	struct scatterlist sgin, sgout;
+	struct blkcipher_desc desc;
+
+	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 " "master crypto API arc4\n");
+		return 1;
+	}
+
+	crypto_blkcipher_setkey(tfm_arc4,
+		server->session_key.data.ntlmv2.key, CIFS_CPHTXT_SIZE);
+	sg_init_one(&sgin, 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)
+		memcpy(server->session_key.data.ntlmv2.key,
+				sec_key, CIFS_NTLMV2_SESSKEY_SIZE);
 
-	hmac_md5_update(v2_session_response+8,
-			sizeof(struct ntlmv2_resp) - 8, &context);
+	crypto_free_blkcipher(tfm_arc4);
 
-	hmac_md5_final(v2_session_response, &context);
-/*	cifs_dump_mem("v2_sess_rsp: ", v2_session_response, 32); */
+	return 0;
+}
+
+void
+cifs_crypto_shash_release(struct TCP_Server_Info *server)
+{
+	if (server->ntlmssp.md5)
+		crypto_free_shash(server->ntlmssp.md5);
+
+	if (server->ntlmssp.hmacmd5)
+		crypto_free_shash(server->ntlmssp.hmacmd5);
+}
+
+int
+cifs_crypto_shash_allocate(struct TCP_Server_Info *server)
+{
+	server->ntlmssp.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);
+	if (!server->ntlmssp.hmacmd5 ||
+			IS_ERR(server->ntlmssp.hmacmd5)) {
+		cERROR(1, "could not allocate master crypto API hmacmd5\n");
+		return 1;
+	}
+
+	server->ntlmssp.md5 = crypto_alloc_shash("md5", 0, 0);
+	if (!server->ntlmssp.md5 || IS_ERR(server->ntlmssp.md5)) {
+		crypto_free_shash(server->ntlmssp.hmacmd5);
+		cERROR(1, "could not allocate master crypto API md5\n");
+		return 1;
+	}
+
+	return 0;
 }