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authorSteve French <stfrench@microsoft.com>2023-05-22 04:46:30 +0300
committerSteve French <stfrench@microsoft.com>2023-05-25 00:29:21 +0300
commit38c8a9a52082579090e34c033d439ed2cd1a462d (patch)
treeca6c3bf5b2b912f32735c1aa0a045cd21a47a205 /fs/smb/server/auth.c
parentcb8b02fd6343228966324528adf920bfb8b8e681 (diff)
downloadlinux-38c8a9a52082579090e34c033d439ed2cd1a462d.tar.xz
smb: move client and server files to common directory fs/smb
Move CIFS/SMB3 related client and server files (cifs.ko and ksmbd.ko and helper modules) to new fs/smb subdirectory: fs/cifs --> fs/smb/client fs/ksmbd --> fs/smb/server fs/smbfs_common --> fs/smb/common Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
Diffstat (limited to 'fs/smb/server/auth.c')
-rw-r--r--fs/smb/server/auth.c1206
1 files changed, 1206 insertions, 0 deletions
diff --git a/fs/smb/server/auth.c b/fs/smb/server/auth.c
new file mode 100644
index 000000000000..5e5e120edcc2
--- /dev/null
+++ b/fs/smb/server/auth.c
@@ -0,0 +1,1206 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2016 Namjae Jeon <linkinjeon@kernel.org>
+ * Copyright (C) 2018 Samsung Electronics Co., Ltd.
+ */
+
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/uaccess.h>
+#include <linux/backing-dev.h>
+#include <linux/writeback.h>
+#include <linux/uio.h>
+#include <linux/xattr.h>
+#include <crypto/hash.h>
+#include <crypto/aead.h>
+#include <linux/random.h>
+#include <linux/scatterlist.h>
+
+#include "auth.h"
+#include "glob.h"
+
+#include <linux/fips.h>
+#include <crypto/des.h>
+
+#include "server.h"
+#include "smb_common.h"
+#include "connection.h"
+#include "mgmt/user_session.h"
+#include "mgmt/user_config.h"
+#include "crypto_ctx.h"
+#include "transport_ipc.h"
+#include "../common/arc4.h"
+
+/*
+ * Fixed format data defining GSS header and fixed string
+ * "not_defined_in_RFC4178@please_ignore".
+ * So sec blob data in neg phase could be generated statically.
+ */
+static char NEGOTIATE_GSS_HEADER[AUTH_GSS_LENGTH] = {
+#ifdef CONFIG_SMB_SERVER_KERBEROS5
+ 0x60, 0x5e, 0x06, 0x06, 0x2b, 0x06, 0x01, 0x05,
+ 0x05, 0x02, 0xa0, 0x54, 0x30, 0x52, 0xa0, 0x24,
+ 0x30, 0x22, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86,
+ 0xf7, 0x12, 0x01, 0x02, 0x02, 0x06, 0x09, 0x2a,
+ 0x86, 0x48, 0x82, 0xf7, 0x12, 0x01, 0x02, 0x02,
+ 0x06, 0x0a, 0x2b, 0x06, 0x01, 0x04, 0x01, 0x82,
+ 0x37, 0x02, 0x02, 0x0a, 0xa3, 0x2a, 0x30, 0x28,
+ 0xa0, 0x26, 0x1b, 0x24, 0x6e, 0x6f, 0x74, 0x5f,
+ 0x64, 0x65, 0x66, 0x69, 0x6e, 0x65, 0x64, 0x5f,
+ 0x69, 0x6e, 0x5f, 0x52, 0x46, 0x43, 0x34, 0x31,
+ 0x37, 0x38, 0x40, 0x70, 0x6c, 0x65, 0x61, 0x73,
+ 0x65, 0x5f, 0x69, 0x67, 0x6e, 0x6f, 0x72, 0x65
+#else
+ 0x60, 0x48, 0x06, 0x06, 0x2b, 0x06, 0x01, 0x05,
+ 0x05, 0x02, 0xa0, 0x3e, 0x30, 0x3c, 0xa0, 0x0e,
+ 0x30, 0x0c, 0x06, 0x0a, 0x2b, 0x06, 0x01, 0x04,
+ 0x01, 0x82, 0x37, 0x02, 0x02, 0x0a, 0xa3, 0x2a,
+ 0x30, 0x28, 0xa0, 0x26, 0x1b, 0x24, 0x6e, 0x6f,
+ 0x74, 0x5f, 0x64, 0x65, 0x66, 0x69, 0x6e, 0x65,
+ 0x64, 0x5f, 0x69, 0x6e, 0x5f, 0x52, 0x46, 0x43,
+ 0x34, 0x31, 0x37, 0x38, 0x40, 0x70, 0x6c, 0x65,
+ 0x61, 0x73, 0x65, 0x5f, 0x69, 0x67, 0x6e, 0x6f,
+ 0x72, 0x65
+#endif
+};
+
+void ksmbd_copy_gss_neg_header(void *buf)
+{
+ memcpy(buf, NEGOTIATE_GSS_HEADER, AUTH_GSS_LENGTH);
+}
+
+/**
+ * ksmbd_gen_sess_key() - function to generate session key
+ * @sess: session of connection
+ * @hash: source hash value to be used for find session key
+ * @hmac: source hmac value to be used for finding session key
+ *
+ */
+static int ksmbd_gen_sess_key(struct ksmbd_session *sess, char *hash,
+ char *hmac)
+{
+ struct ksmbd_crypto_ctx *ctx;
+ int rc;
+
+ ctx = ksmbd_crypto_ctx_find_hmacmd5();
+ if (!ctx) {
+ ksmbd_debug(AUTH, "could not crypto alloc hmacmd5\n");
+ return -ENOMEM;
+ }
+
+ rc = crypto_shash_setkey(CRYPTO_HMACMD5_TFM(ctx),
+ hash,
+ CIFS_HMAC_MD5_HASH_SIZE);
+ if (rc) {
+ ksmbd_debug(AUTH, "hmacmd5 set key fail error %d\n", rc);
+ goto out;
+ }
+
+ rc = crypto_shash_init(CRYPTO_HMACMD5(ctx));
+ if (rc) {
+ ksmbd_debug(AUTH, "could not init hmacmd5 error %d\n", rc);
+ goto out;
+ }
+
+ rc = crypto_shash_update(CRYPTO_HMACMD5(ctx),
+ hmac,
+ SMB2_NTLMV2_SESSKEY_SIZE);
+ if (rc) {
+ ksmbd_debug(AUTH, "Could not update with response error %d\n", rc);
+ goto out;
+ }
+
+ rc = crypto_shash_final(CRYPTO_HMACMD5(ctx), sess->sess_key);
+ if (rc) {
+ ksmbd_debug(AUTH, "Could not generate hmacmd5 hash error %d\n", rc);
+ goto out;
+ }
+
+out:
+ ksmbd_release_crypto_ctx(ctx);
+ return rc;
+}
+
+static int calc_ntlmv2_hash(struct ksmbd_conn *conn, struct ksmbd_session *sess,
+ char *ntlmv2_hash, char *dname)
+{
+ int ret, len, conv_len;
+ wchar_t *domain = NULL;
+ __le16 *uniname = NULL;
+ struct ksmbd_crypto_ctx *ctx;
+
+ ctx = ksmbd_crypto_ctx_find_hmacmd5();
+ if (!ctx) {
+ ksmbd_debug(AUTH, "can't generate ntlmv2 hash\n");
+ return -ENOMEM;
+ }
+
+ ret = crypto_shash_setkey(CRYPTO_HMACMD5_TFM(ctx),
+ user_passkey(sess->user),
+ CIFS_ENCPWD_SIZE);
+ if (ret) {
+ ksmbd_debug(AUTH, "Could not set NT Hash as a key\n");
+ goto out;
+ }
+
+ ret = crypto_shash_init(CRYPTO_HMACMD5(ctx));
+ if (ret) {
+ ksmbd_debug(AUTH, "could not init hmacmd5\n");
+ goto out;
+ }
+
+ /* convert user_name to unicode */
+ len = strlen(user_name(sess->user));
+ uniname = kzalloc(2 + UNICODE_LEN(len), GFP_KERNEL);
+ if (!uniname) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ conv_len = smb_strtoUTF16(uniname, user_name(sess->user), len,
+ conn->local_nls);
+ if (conv_len < 0 || conv_len > len) {
+ ret = -EINVAL;
+ goto out;
+ }
+ UniStrupr(uniname);
+
+ ret = crypto_shash_update(CRYPTO_HMACMD5(ctx),
+ (char *)uniname,
+ UNICODE_LEN(conv_len));
+ if (ret) {
+ ksmbd_debug(AUTH, "Could not update with user\n");
+ goto out;
+ }
+
+ /* Convert domain name or conn name to unicode and uppercase */
+ len = strlen(dname);
+ domain = kzalloc(2 + UNICODE_LEN(len), GFP_KERNEL);
+ if (!domain) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ conv_len = smb_strtoUTF16((__le16 *)domain, dname, len,
+ conn->local_nls);
+ if (conv_len < 0 || conv_len > len) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = crypto_shash_update(CRYPTO_HMACMD5(ctx),
+ (char *)domain,
+ UNICODE_LEN(conv_len));
+ if (ret) {
+ ksmbd_debug(AUTH, "Could not update with domain\n");
+ goto out;
+ }
+
+ ret = crypto_shash_final(CRYPTO_HMACMD5(ctx), ntlmv2_hash);
+ if (ret)
+ ksmbd_debug(AUTH, "Could not generate md5 hash\n");
+out:
+ kfree(uniname);
+ kfree(domain);
+ ksmbd_release_crypto_ctx(ctx);
+ return ret;
+}
+
+/**
+ * ksmbd_auth_ntlmv2() - NTLMv2 authentication handler
+ * @sess: session of connection
+ * @ntlmv2: NTLMv2 challenge response
+ * @blen: NTLMv2 blob length
+ * @domain_name: domain name
+ *
+ * Return: 0 on success, error number on error
+ */
+int ksmbd_auth_ntlmv2(struct ksmbd_conn *conn, struct ksmbd_session *sess,
+ struct ntlmv2_resp *ntlmv2, int blen, char *domain_name,
+ char *cryptkey)
+{
+ char ntlmv2_hash[CIFS_ENCPWD_SIZE];
+ char ntlmv2_rsp[CIFS_HMAC_MD5_HASH_SIZE];
+ struct ksmbd_crypto_ctx *ctx = NULL;
+ char *construct = NULL;
+ int rc, len;
+
+ rc = calc_ntlmv2_hash(conn, sess, ntlmv2_hash, domain_name);
+ if (rc) {
+ ksmbd_debug(AUTH, "could not get v2 hash rc %d\n", rc);
+ goto out;
+ }
+
+ ctx = ksmbd_crypto_ctx_find_hmacmd5();
+ if (!ctx) {
+ ksmbd_debug(AUTH, "could not crypto alloc hmacmd5\n");
+ return -ENOMEM;
+ }
+
+ rc = crypto_shash_setkey(CRYPTO_HMACMD5_TFM(ctx),
+ ntlmv2_hash,
+ CIFS_HMAC_MD5_HASH_SIZE);
+ if (rc) {
+ ksmbd_debug(AUTH, "Could not set NTLMV2 Hash as a key\n");
+ goto out;
+ }
+
+ rc = crypto_shash_init(CRYPTO_HMACMD5(ctx));
+ if (rc) {
+ ksmbd_debug(AUTH, "Could not init hmacmd5\n");
+ goto out;
+ }
+
+ len = CIFS_CRYPTO_KEY_SIZE + blen;
+ construct = kzalloc(len, GFP_KERNEL);
+ if (!construct) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ memcpy(construct, cryptkey, CIFS_CRYPTO_KEY_SIZE);
+ memcpy(construct + CIFS_CRYPTO_KEY_SIZE, &ntlmv2->blob_signature, blen);
+
+ rc = crypto_shash_update(CRYPTO_HMACMD5(ctx), construct, len);
+ if (rc) {
+ ksmbd_debug(AUTH, "Could not update with response\n");
+ goto out;
+ }
+
+ rc = crypto_shash_final(CRYPTO_HMACMD5(ctx), ntlmv2_rsp);
+ if (rc) {
+ ksmbd_debug(AUTH, "Could not generate md5 hash\n");
+ goto out;
+ }
+ ksmbd_release_crypto_ctx(ctx);
+ ctx = NULL;
+
+ rc = ksmbd_gen_sess_key(sess, ntlmv2_hash, ntlmv2_rsp);
+ if (rc) {
+ ksmbd_debug(AUTH, "Could not generate sess key\n");
+ goto out;
+ }
+
+ if (memcmp(ntlmv2->ntlmv2_hash, ntlmv2_rsp, CIFS_HMAC_MD5_HASH_SIZE) != 0)
+ rc = -EINVAL;
+out:
+ if (ctx)
+ ksmbd_release_crypto_ctx(ctx);
+ kfree(construct);
+ return rc;
+}
+
+/**
+ * ksmbd_decode_ntlmssp_auth_blob() - helper function to construct
+ * authenticate blob
+ * @authblob: authenticate blob source pointer
+ * @usr: user details
+ * @sess: session of connection
+ *
+ * Return: 0 on success, error number on error
+ */
+int ksmbd_decode_ntlmssp_auth_blob(struct authenticate_message *authblob,
+ int blob_len, struct ksmbd_conn *conn,
+ struct ksmbd_session *sess)
+{
+ char *domain_name;
+ unsigned int nt_off, dn_off;
+ unsigned short nt_len, dn_len;
+ int ret;
+
+ if (blob_len < sizeof(struct authenticate_message)) {
+ ksmbd_debug(AUTH, "negotiate blob len %d too small\n",
+ blob_len);
+ return -EINVAL;
+ }
+
+ if (memcmp(authblob->Signature, "NTLMSSP", 8)) {
+ ksmbd_debug(AUTH, "blob signature incorrect %s\n",
+ authblob->Signature);
+ return -EINVAL;
+ }
+
+ nt_off = le32_to_cpu(authblob->NtChallengeResponse.BufferOffset);
+ nt_len = le16_to_cpu(authblob->NtChallengeResponse.Length);
+ dn_off = le32_to_cpu(authblob->DomainName.BufferOffset);
+ dn_len = le16_to_cpu(authblob->DomainName.Length);
+
+ if (blob_len < (u64)dn_off + dn_len || blob_len < (u64)nt_off + nt_len ||
+ nt_len < CIFS_ENCPWD_SIZE)
+ return -EINVAL;
+
+ /* TODO : use domain name that imported from configuration file */
+ domain_name = smb_strndup_from_utf16((const char *)authblob + dn_off,
+ dn_len, true, conn->local_nls);
+ if (IS_ERR(domain_name))
+ return PTR_ERR(domain_name);
+
+ /* process NTLMv2 authentication */
+ ksmbd_debug(AUTH, "decode_ntlmssp_authenticate_blob dname%s\n",
+ domain_name);
+ ret = ksmbd_auth_ntlmv2(conn, sess,
+ (struct ntlmv2_resp *)((char *)authblob + nt_off),
+ nt_len - CIFS_ENCPWD_SIZE,
+ domain_name, conn->ntlmssp.cryptkey);
+ kfree(domain_name);
+
+ /* The recovered secondary session key */
+ if (conn->ntlmssp.client_flags & NTLMSSP_NEGOTIATE_KEY_XCH) {
+ struct arc4_ctx *ctx_arc4;
+ unsigned int sess_key_off, sess_key_len;
+
+ sess_key_off = le32_to_cpu(authblob->SessionKey.BufferOffset);
+ sess_key_len = le16_to_cpu(authblob->SessionKey.Length);
+
+ if (blob_len < (u64)sess_key_off + sess_key_len)
+ return -EINVAL;
+
+ ctx_arc4 = kmalloc(sizeof(*ctx_arc4), GFP_KERNEL);
+ if (!ctx_arc4)
+ return -ENOMEM;
+
+ cifs_arc4_setkey(ctx_arc4, sess->sess_key,
+ SMB2_NTLMV2_SESSKEY_SIZE);
+ cifs_arc4_crypt(ctx_arc4, sess->sess_key,
+ (char *)authblob + sess_key_off, sess_key_len);
+ kfree_sensitive(ctx_arc4);
+ }
+
+ return ret;
+}
+
+/**
+ * ksmbd_decode_ntlmssp_neg_blob() - helper function to construct
+ * negotiate blob
+ * @negblob: negotiate blob source pointer
+ * @rsp: response header pointer to be updated
+ * @sess: session of connection
+ *
+ */
+int ksmbd_decode_ntlmssp_neg_blob(struct negotiate_message *negblob,
+ int blob_len, struct ksmbd_conn *conn)
+{
+ if (blob_len < sizeof(struct negotiate_message)) {
+ ksmbd_debug(AUTH, "negotiate blob len %d too small\n",
+ blob_len);
+ return -EINVAL;
+ }
+
+ if (memcmp(negblob->Signature, "NTLMSSP", 8)) {
+ ksmbd_debug(AUTH, "blob signature incorrect %s\n",
+ negblob->Signature);
+ return -EINVAL;
+ }
+
+ conn->ntlmssp.client_flags = le32_to_cpu(negblob->NegotiateFlags);
+ return 0;
+}
+
+/**
+ * ksmbd_build_ntlmssp_challenge_blob() - helper function to construct
+ * challenge blob
+ * @chgblob: challenge blob source pointer to initialize
+ * @rsp: response header pointer to be updated
+ * @sess: session of connection
+ *
+ */
+unsigned int
+ksmbd_build_ntlmssp_challenge_blob(struct challenge_message *chgblob,
+ struct ksmbd_conn *conn)
+{
+ struct target_info *tinfo;
+ wchar_t *name;
+ __u8 *target_name;
+ unsigned int flags, blob_off, blob_len, type, target_info_len = 0;
+ int len, uni_len, conv_len;
+ int cflags = conn->ntlmssp.client_flags;
+
+ memcpy(chgblob->Signature, NTLMSSP_SIGNATURE, 8);
+ chgblob->MessageType = NtLmChallenge;
+
+ flags = NTLMSSP_NEGOTIATE_UNICODE |
+ NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_TARGET_TYPE_SERVER |
+ NTLMSSP_NEGOTIATE_TARGET_INFO;
+
+ if (cflags & NTLMSSP_NEGOTIATE_SIGN) {
+ flags |= NTLMSSP_NEGOTIATE_SIGN;
+ flags |= cflags & (NTLMSSP_NEGOTIATE_128 |
+ NTLMSSP_NEGOTIATE_56);
+ }
+
+ if (cflags & NTLMSSP_NEGOTIATE_SEAL && smb3_encryption_negotiated(conn))
+ flags |= NTLMSSP_NEGOTIATE_SEAL;
+
+ if (cflags & NTLMSSP_NEGOTIATE_ALWAYS_SIGN)
+ flags |= NTLMSSP_NEGOTIATE_ALWAYS_SIGN;
+
+ if (cflags & NTLMSSP_REQUEST_TARGET)
+ flags |= NTLMSSP_REQUEST_TARGET;
+
+ if (conn->use_spnego &&
+ (cflags & NTLMSSP_NEGOTIATE_EXTENDED_SEC))
+ flags |= NTLMSSP_NEGOTIATE_EXTENDED_SEC;
+
+ if (cflags & NTLMSSP_NEGOTIATE_KEY_XCH)
+ flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
+
+ chgblob->NegotiateFlags = cpu_to_le32(flags);
+ len = strlen(ksmbd_netbios_name());
+ name = kmalloc(2 + UNICODE_LEN(len), GFP_KERNEL);
+ if (!name)
+ return -ENOMEM;
+
+ conv_len = smb_strtoUTF16((__le16 *)name, ksmbd_netbios_name(), len,
+ conn->local_nls);
+ if (conv_len < 0 || conv_len > len) {
+ kfree(name);
+ return -EINVAL;
+ }
+
+ uni_len = UNICODE_LEN(conv_len);
+
+ blob_off = sizeof(struct challenge_message);
+ blob_len = blob_off + uni_len;
+
+ chgblob->TargetName.Length = cpu_to_le16(uni_len);
+ chgblob->TargetName.MaximumLength = cpu_to_le16(uni_len);
+ chgblob->TargetName.BufferOffset = cpu_to_le32(blob_off);
+
+ /* Initialize random conn challenge */
+ get_random_bytes(conn->ntlmssp.cryptkey, sizeof(__u64));
+ memcpy(chgblob->Challenge, conn->ntlmssp.cryptkey,
+ CIFS_CRYPTO_KEY_SIZE);
+
+ /* Add Target Information to security buffer */
+ chgblob->TargetInfoArray.BufferOffset = cpu_to_le32(blob_len);
+
+ target_name = (__u8 *)chgblob + blob_off;
+ memcpy(target_name, name, uni_len);
+ tinfo = (struct target_info *)(target_name + uni_len);
+
+ chgblob->TargetInfoArray.Length = 0;
+ /* Add target info list for NetBIOS/DNS settings */
+ for (type = NTLMSSP_AV_NB_COMPUTER_NAME;
+ type <= NTLMSSP_AV_DNS_DOMAIN_NAME; type++) {
+ tinfo->Type = cpu_to_le16(type);
+ tinfo->Length = cpu_to_le16(uni_len);
+ memcpy(tinfo->Content, name, uni_len);
+ tinfo = (struct target_info *)((char *)tinfo + 4 + uni_len);
+ target_info_len += 4 + uni_len;
+ }
+
+ /* Add terminator subblock */
+ tinfo->Type = 0;
+ tinfo->Length = 0;
+ target_info_len += 4;
+
+ chgblob->TargetInfoArray.Length = cpu_to_le16(target_info_len);
+ chgblob->TargetInfoArray.MaximumLength = cpu_to_le16(target_info_len);
+ blob_len += target_info_len;
+ kfree(name);
+ ksmbd_debug(AUTH, "NTLMSSP SecurityBufferLength %d\n", blob_len);
+ return blob_len;
+}
+
+#ifdef CONFIG_SMB_SERVER_KERBEROS5
+int ksmbd_krb5_authenticate(struct ksmbd_session *sess, char *in_blob,
+ int in_len, char *out_blob, int *out_len)
+{
+ struct ksmbd_spnego_authen_response *resp;
+ struct ksmbd_user *user = NULL;
+ int retval;
+
+ resp = ksmbd_ipc_spnego_authen_request(in_blob, in_len);
+ if (!resp) {
+ ksmbd_debug(AUTH, "SPNEGO_AUTHEN_REQUEST failure\n");
+ return -EINVAL;
+ }
+
+ if (!(resp->login_response.status & KSMBD_USER_FLAG_OK)) {
+ ksmbd_debug(AUTH, "krb5 authentication failure\n");
+ retval = -EPERM;
+ goto out;
+ }
+
+ if (*out_len <= resp->spnego_blob_len) {
+ ksmbd_debug(AUTH, "buf len %d, but blob len %d\n",
+ *out_len, resp->spnego_blob_len);
+ retval = -EINVAL;
+ goto out;
+ }
+
+ if (resp->session_key_len > sizeof(sess->sess_key)) {
+ ksmbd_debug(AUTH, "session key is too long\n");
+ retval = -EINVAL;
+ goto out;
+ }
+
+ user = ksmbd_alloc_user(&resp->login_response);
+ if (!user) {
+ ksmbd_debug(AUTH, "login failure\n");
+ retval = -ENOMEM;
+ goto out;
+ }
+ sess->user = user;
+
+ memcpy(sess->sess_key, resp->payload, resp->session_key_len);
+ memcpy(out_blob, resp->payload + resp->session_key_len,
+ resp->spnego_blob_len);
+ *out_len = resp->spnego_blob_len;
+ retval = 0;
+out:
+ kvfree(resp);
+ return retval;
+}
+#else
+int ksmbd_krb5_authenticate(struct ksmbd_session *sess, char *in_blob,
+ int in_len, char *out_blob, int *out_len)
+{
+ return -EOPNOTSUPP;
+}
+#endif
+
+/**
+ * ksmbd_sign_smb2_pdu() - function to generate packet signing
+ * @conn: connection
+ * @key: signing key
+ * @iov: buffer iov array
+ * @n_vec: number of iovecs
+ * @sig: signature value generated for client request packet
+ *
+ */
+int ksmbd_sign_smb2_pdu(struct ksmbd_conn *conn, char *key, struct kvec *iov,
+ int n_vec, char *sig)
+{
+ struct ksmbd_crypto_ctx *ctx;
+ int rc, i;
+
+ ctx = ksmbd_crypto_ctx_find_hmacsha256();
+ if (!ctx) {
+ ksmbd_debug(AUTH, "could not crypto alloc hmacmd5\n");
+ return -ENOMEM;
+ }
+
+ rc = crypto_shash_setkey(CRYPTO_HMACSHA256_TFM(ctx),
+ key,
+ SMB2_NTLMV2_SESSKEY_SIZE);
+ if (rc)
+ goto out;
+
+ rc = crypto_shash_init(CRYPTO_HMACSHA256(ctx));
+ if (rc) {
+ ksmbd_debug(AUTH, "hmacsha256 init error %d\n", rc);
+ goto out;
+ }
+
+ for (i = 0; i < n_vec; i++) {
+ rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx),
+ iov[i].iov_base,
+ iov[i].iov_len);
+ if (rc) {
+ ksmbd_debug(AUTH, "hmacsha256 update error %d\n", rc);
+ goto out;
+ }
+ }
+
+ rc = crypto_shash_final(CRYPTO_HMACSHA256(ctx), sig);
+ if (rc)
+ ksmbd_debug(AUTH, "hmacsha256 generation error %d\n", rc);
+out:
+ ksmbd_release_crypto_ctx(ctx);
+ return rc;
+}
+
+/**
+ * ksmbd_sign_smb3_pdu() - function to generate packet signing
+ * @conn: connection
+ * @key: signing key
+ * @iov: buffer iov array
+ * @n_vec: number of iovecs
+ * @sig: signature value generated for client request packet
+ *
+ */
+int ksmbd_sign_smb3_pdu(struct ksmbd_conn *conn, char *key, struct kvec *iov,
+ int n_vec, char *sig)
+{
+ struct ksmbd_crypto_ctx *ctx;
+ int rc, i;
+
+ ctx = ksmbd_crypto_ctx_find_cmacaes();
+ if (!ctx) {
+ ksmbd_debug(AUTH, "could not crypto alloc cmac\n");
+ return -ENOMEM;
+ }
+
+ rc = crypto_shash_setkey(CRYPTO_CMACAES_TFM(ctx),
+ key,
+ SMB2_CMACAES_SIZE);
+ if (rc)
+ goto out;
+
+ rc = crypto_shash_init(CRYPTO_CMACAES(ctx));
+ if (rc) {
+ ksmbd_debug(AUTH, "cmaces init error %d\n", rc);
+ goto out;
+ }
+
+ for (i = 0; i < n_vec; i++) {
+ rc = crypto_shash_update(CRYPTO_CMACAES(ctx),
+ iov[i].iov_base,
+ iov[i].iov_len);
+ if (rc) {
+ ksmbd_debug(AUTH, "cmaces update error %d\n", rc);
+ goto out;
+ }
+ }
+
+ rc = crypto_shash_final(CRYPTO_CMACAES(ctx), sig);
+ if (rc)
+ ksmbd_debug(AUTH, "cmaces generation error %d\n", rc);
+out:
+ ksmbd_release_crypto_ctx(ctx);
+ return rc;
+}
+
+struct derivation {
+ struct kvec label;
+ struct kvec context;
+ bool binding;
+};
+
+static int generate_key(struct ksmbd_conn *conn, struct ksmbd_session *sess,
+ 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;
+ unsigned char prfhash[SMB2_HMACSHA256_SIZE];
+ unsigned char *hashptr = prfhash;
+ struct ksmbd_crypto_ctx *ctx;
+
+ memset(prfhash, 0x0, SMB2_HMACSHA256_SIZE);
+ memset(key, 0x0, key_size);
+
+ ctx = ksmbd_crypto_ctx_find_hmacsha256();
+ if (!ctx) {
+ ksmbd_debug(AUTH, "could not crypto alloc hmacmd5\n");
+ return -ENOMEM;
+ }
+
+ rc = crypto_shash_setkey(CRYPTO_HMACSHA256_TFM(ctx),
+ sess->sess_key,
+ SMB2_NTLMV2_SESSKEY_SIZE);
+ if (rc)
+ goto smb3signkey_ret;
+
+ rc = crypto_shash_init(CRYPTO_HMACSHA256(ctx));
+ if (rc) {
+ ksmbd_debug(AUTH, "hmacsha256 init error %d\n", rc);
+ goto smb3signkey_ret;
+ }
+
+ rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx), i, 4);
+ if (rc) {
+ ksmbd_debug(AUTH, "could not update with n\n");
+ goto smb3signkey_ret;
+ }
+
+ rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx),
+ label.iov_base,
+ label.iov_len);
+ if (rc) {
+ ksmbd_debug(AUTH, "could not update with label\n");
+ goto smb3signkey_ret;
+ }
+
+ rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx), &zero, 1);
+ if (rc) {
+ ksmbd_debug(AUTH, "could not update with zero\n");
+ goto smb3signkey_ret;
+ }
+
+ rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx),
+ context.iov_base,
+ context.iov_len);
+ if (rc) {
+ ksmbd_debug(AUTH, "could not update with context\n");
+ goto smb3signkey_ret;
+ }
+
+ if (key_size == SMB3_ENC_DEC_KEY_SIZE &&
+ (conn->cipher_type == SMB2_ENCRYPTION_AES256_CCM ||
+ conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM))
+ rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx), L256, 4);
+ else
+ rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx), L128, 4);
+ if (rc) {
+ ksmbd_debug(AUTH, "could not update with L\n");
+ goto smb3signkey_ret;
+ }
+
+ rc = crypto_shash_final(CRYPTO_HMACSHA256(ctx), hashptr);
+ if (rc) {
+ ksmbd_debug(AUTH, "Could not generate hmacmd5 hash error %d\n",
+ rc);
+ goto smb3signkey_ret;
+ }
+
+ memcpy(key, hashptr, key_size);
+
+smb3signkey_ret:
+ ksmbd_release_crypto_ctx(ctx);
+ return rc;
+}
+
+static int generate_smb3signingkey(struct ksmbd_session *sess,
+ struct ksmbd_conn *conn,
+ const struct derivation *signing)
+{
+ int rc;
+ struct channel *chann;
+ char *key;
+
+ chann = lookup_chann_list(sess, conn);
+ if (!chann)
+ return 0;
+
+ if (conn->dialect >= SMB30_PROT_ID && signing->binding)
+ key = chann->smb3signingkey;
+ else
+ key = sess->smb3signingkey;
+
+ rc = generate_key(conn, sess, signing->label, signing->context, key,
+ SMB3_SIGN_KEY_SIZE);
+ if (rc)
+ return rc;
+
+ if (!(conn->dialect >= SMB30_PROT_ID && signing->binding))
+ memcpy(chann->smb3signingkey, key, SMB3_SIGN_KEY_SIZE);
+
+ ksmbd_debug(AUTH, "dumping generated AES signing keys\n");
+ ksmbd_debug(AUTH, "Session Id %llu\n", sess->id);
+ ksmbd_debug(AUTH, "Session Key %*ph\n",
+ SMB2_NTLMV2_SESSKEY_SIZE, sess->sess_key);
+ ksmbd_debug(AUTH, "Signing Key %*ph\n",
+ SMB3_SIGN_KEY_SIZE, key);
+ return 0;
+}
+
+int ksmbd_gen_smb30_signingkey(struct ksmbd_session *sess,
+ struct ksmbd_conn *conn)
+{
+ struct derivation d;
+
+ d.label.iov_base = "SMB2AESCMAC";
+ d.label.iov_len = 12;
+ d.context.iov_base = "SmbSign";
+ d.context.iov_len = 8;
+ d.binding = conn->binding;
+
+ return generate_smb3signingkey(sess, conn, &d);
+}
+
+int ksmbd_gen_smb311_signingkey(struct ksmbd_session *sess,
+ struct ksmbd_conn *conn)
+{
+ struct derivation d;
+
+ d.label.iov_base = "SMBSigningKey";
+ d.label.iov_len = 14;
+ if (conn->binding) {
+ struct preauth_session *preauth_sess;
+
+ preauth_sess = ksmbd_preauth_session_lookup(conn, sess->id);
+ if (!preauth_sess)
+ return -ENOENT;
+ d.context.iov_base = preauth_sess->Preauth_HashValue;
+ } else {
+ d.context.iov_base = sess->Preauth_HashValue;
+ }
+ d.context.iov_len = 64;
+ d.binding = conn->binding;
+
+ return generate_smb3signingkey(sess, conn, &d);
+}
+
+struct derivation_twin {
+ struct derivation encryption;
+ struct derivation decryption;
+};
+
+static int generate_smb3encryptionkey(struct ksmbd_conn *conn,
+ struct ksmbd_session *sess,
+ const struct derivation_twin *ptwin)
+{
+ int rc;
+
+ rc = generate_key(conn, sess, ptwin->encryption.label,
+ ptwin->encryption.context, sess->smb3encryptionkey,
+ SMB3_ENC_DEC_KEY_SIZE);
+ if (rc)
+ return rc;
+
+ rc = generate_key(conn, sess, ptwin->decryption.label,
+ ptwin->decryption.context,
+ sess->smb3decryptionkey, SMB3_ENC_DEC_KEY_SIZE);
+ if (rc)
+ return rc;
+
+ ksmbd_debug(AUTH, "dumping generated AES encryption keys\n");
+ ksmbd_debug(AUTH, "Cipher type %d\n", conn->cipher_type);
+ ksmbd_debug(AUTH, "Session Id %llu\n", sess->id);
+ ksmbd_debug(AUTH, "Session Key %*ph\n",
+ SMB2_NTLMV2_SESSKEY_SIZE, sess->sess_key);
+ if (conn->cipher_type == SMB2_ENCRYPTION_AES256_CCM ||
+ conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM) {
+ ksmbd_debug(AUTH, "ServerIn Key %*ph\n",
+ SMB3_GCM256_CRYPTKEY_SIZE, sess->smb3encryptionkey);
+ ksmbd_debug(AUTH, "ServerOut Key %*ph\n",
+ SMB3_GCM256_CRYPTKEY_SIZE, sess->smb3decryptionkey);
+ } else {
+ ksmbd_debug(AUTH, "ServerIn Key %*ph\n",
+ SMB3_GCM128_CRYPTKEY_SIZE, sess->smb3encryptionkey);
+ ksmbd_debug(AUTH, "ServerOut Key %*ph\n",
+ SMB3_GCM128_CRYPTKEY_SIZE, sess->smb3decryptionkey);
+ }
+ return 0;
+}
+
+int ksmbd_gen_smb30_encryptionkey(struct ksmbd_conn *conn,
+ struct ksmbd_session *sess)
+{
+ struct derivation_twin twin;
+ struct derivation *d;
+
+ d = &twin.encryption;
+ d->label.iov_base = "SMB2AESCCM";
+ d->label.iov_len = 11;
+ d->context.iov_base = "ServerOut";
+ d->context.iov_len = 10;
+
+ d = &twin.decryption;
+ d->label.iov_base = "SMB2AESCCM";
+ d->label.iov_len = 11;
+ d->context.iov_base = "ServerIn ";
+ d->context.iov_len = 10;
+
+ return generate_smb3encryptionkey(conn, sess, &twin);
+}
+
+int ksmbd_gen_smb311_encryptionkey(struct ksmbd_conn *conn,
+ struct ksmbd_session *sess)
+{
+ struct derivation_twin twin;
+ struct derivation *d;
+
+ d = &twin.encryption;
+ d->label.iov_base = "SMBS2CCipherKey";
+ d->label.iov_len = 16;
+ d->context.iov_base = sess->Preauth_HashValue;
+ d->context.iov_len = 64;
+
+ d = &twin.decryption;
+ d->label.iov_base = "SMBC2SCipherKey";
+ d->label.iov_len = 16;
+ d->context.iov_base = sess->Preauth_HashValue;
+ d->context.iov_len = 64;
+
+ return generate_smb3encryptionkey(conn, sess, &twin);
+}
+
+int ksmbd_gen_preauth_integrity_hash(struct ksmbd_conn *conn, char *buf,
+ __u8 *pi_hash)
+{
+ int rc;
+ struct smb2_hdr *rcv_hdr = smb2_get_msg(buf);
+ char *all_bytes_msg = (char *)&rcv_hdr->ProtocolId;
+ int msg_size = get_rfc1002_len(buf);
+ struct ksmbd_crypto_ctx *ctx = NULL;
+
+ if (conn->preauth_info->Preauth_HashId !=
+ SMB2_PREAUTH_INTEGRITY_SHA512)
+ return -EINVAL;
+
+ ctx = ksmbd_crypto_ctx_find_sha512();
+ if (!ctx) {
+ ksmbd_debug(AUTH, "could not alloc sha512\n");
+ return -ENOMEM;
+ }
+
+ rc = crypto_shash_init(CRYPTO_SHA512(ctx));
+ if (rc) {
+ ksmbd_debug(AUTH, "could not init shashn");
+ goto out;
+ }
+
+ rc = crypto_shash_update(CRYPTO_SHA512(ctx), pi_hash, 64);
+ if (rc) {
+ ksmbd_debug(AUTH, "could not update with n\n");
+ goto out;
+ }
+
+ rc = crypto_shash_update(CRYPTO_SHA512(ctx), all_bytes_msg, msg_size);
+ if (rc) {
+ ksmbd_debug(AUTH, "could not update with n\n");
+ goto out;
+ }
+
+ rc = crypto_shash_final(CRYPTO_SHA512(ctx), pi_hash);
+ if (rc) {
+ ksmbd_debug(AUTH, "Could not generate hash err : %d\n", rc);
+ goto out;
+ }
+out:
+ ksmbd_release_crypto_ctx(ctx);
+ return rc;
+}
+
+int ksmbd_gen_sd_hash(struct ksmbd_conn *conn, char *sd_buf, int len,
+ __u8 *pi_hash)
+{
+ int rc;
+ struct ksmbd_crypto_ctx *ctx = NULL;
+
+ ctx = ksmbd_crypto_ctx_find_sha256();
+ if (!ctx) {
+ ksmbd_debug(AUTH, "could not alloc sha256\n");
+ return -ENOMEM;
+ }
+
+ rc = crypto_shash_init(CRYPTO_SHA256(ctx));
+ if (rc) {
+ ksmbd_debug(AUTH, "could not init shashn");
+ goto out;
+ }
+
+ rc = crypto_shash_update(CRYPTO_SHA256(ctx), sd_buf, len);
+ if (rc) {
+ ksmbd_debug(AUTH, "could not update with n\n");
+ goto out;
+ }
+
+ rc = crypto_shash_final(CRYPTO_SHA256(ctx), pi_hash);
+ if (rc) {
+ ksmbd_debug(AUTH, "Could not generate hash err : %d\n", rc);
+ goto out;
+ }
+out:
+ ksmbd_release_crypto_ctx(ctx);
+ return rc;
+}
+
+static int ksmbd_get_encryption_key(struct ksmbd_work *work, __u64 ses_id,
+ int enc, u8 *key)
+{
+ struct ksmbd_session *sess;
+ u8 *ses_enc_key;
+
+ if (enc)
+ sess = work->sess;
+ else
+ sess = ksmbd_session_lookup_all(work->conn, ses_id);
+ if (!sess)
+ return -EINVAL;
+
+ ses_enc_key = enc ? sess->smb3encryptionkey :
+ sess->smb3decryptionkey;
+ memcpy(key, ses_enc_key, SMB3_ENC_DEC_KEY_SIZE);
+
+ return 0;
+}
+
+static inline void smb2_sg_set_buf(struct scatterlist *sg, const void *buf,
+ unsigned int buflen)
+{
+ void *addr;
+
+ if (is_vmalloc_addr(buf))
+ addr = vmalloc_to_page(buf);
+ else
+ addr = virt_to_page(buf);
+ sg_set_page(sg, addr, buflen, offset_in_page(buf));
+}
+
+static struct scatterlist *ksmbd_init_sg(struct kvec *iov, unsigned int nvec,
+ u8 *sign)
+{
+ struct scatterlist *sg;
+ unsigned int assoc_data_len = sizeof(struct smb2_transform_hdr) - 20;
+ int i, nr_entries[3] = {0}, total_entries = 0, sg_idx = 0;
+
+ if (!nvec)
+ return NULL;
+
+ for (i = 0; i < nvec - 1; i++) {
+ unsigned long kaddr = (unsigned long)iov[i + 1].iov_base;
+
+ if (is_vmalloc_addr(iov[i + 1].iov_base)) {
+ nr_entries[i] = ((kaddr + iov[i + 1].iov_len +
+ PAGE_SIZE - 1) >> PAGE_SHIFT) -
+ (kaddr >> PAGE_SHIFT);
+ } else {
+ nr_entries[i]++;
+ }
+ total_entries += nr_entries[i];
+ }
+
+ /* Add two entries for transform header and signature */
+ total_entries += 2;
+
+ sg = kmalloc_array(total_entries, sizeof(struct scatterlist), GFP_KERNEL);
+ if (!sg)
+ return NULL;
+
+ sg_init_table(sg, total_entries);
+ smb2_sg_set_buf(&sg[sg_idx++], iov[0].iov_base + 24, assoc_data_len);
+ for (i = 0; i < nvec - 1; i++) {
+ void *data = iov[i + 1].iov_base;
+ int len = iov[i + 1].iov_len;
+
+ if (is_vmalloc_addr(data)) {
+ int j, offset = offset_in_page(data);
+
+ for (j = 0; j < nr_entries[i]; j++) {
+ unsigned int bytes = PAGE_SIZE - offset;
+
+ if (!len)
+ break;
+
+ if (bytes > len)
+ bytes = len;
+
+ sg_set_page(&sg[sg_idx++],
+ vmalloc_to_page(data), bytes,
+ offset_in_page(data));
+
+ data += bytes;
+ len -= bytes;
+ offset = 0;
+ }
+ } else {
+ sg_set_page(&sg[sg_idx++], virt_to_page(data), len,
+ offset_in_page(data));
+ }
+ }
+ smb2_sg_set_buf(&sg[sg_idx], sign, SMB2_SIGNATURE_SIZE);
+ return sg;
+}
+
+int ksmbd_crypt_message(struct ksmbd_work *work, struct kvec *iov,
+ unsigned int nvec, int enc)
+{
+ struct ksmbd_conn *conn = work->conn;
+ struct smb2_transform_hdr *tr_hdr = smb2_get_msg(iov[0].iov_base);
+ unsigned int assoc_data_len = sizeof(struct smb2_transform_hdr) - 20;
+ int rc;
+ struct scatterlist *sg;
+ u8 sign[SMB2_SIGNATURE_SIZE] = {};
+ u8 key[SMB3_ENC_DEC_KEY_SIZE];
+ struct aead_request *req;
+ char *iv;
+ unsigned int iv_len;
+ struct crypto_aead *tfm;
+ unsigned int crypt_len = le32_to_cpu(tr_hdr->OriginalMessageSize);
+ struct ksmbd_crypto_ctx *ctx;
+
+ rc = ksmbd_get_encryption_key(work,
+ le64_to_cpu(tr_hdr->SessionId),
+ enc,
+ key);
+ if (rc) {
+ pr_err("Could not get %scryption key\n", enc ? "en" : "de");
+ return rc;
+ }
+
+ if (conn->cipher_type == SMB2_ENCRYPTION_AES128_GCM ||
+ conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM)
+ ctx = ksmbd_crypto_ctx_find_gcm();
+ else
+ ctx = ksmbd_crypto_ctx_find_ccm();
+ if (!ctx) {
+ pr_err("crypto alloc failed\n");
+ return -ENOMEM;
+ }
+
+ if (conn->cipher_type == SMB2_ENCRYPTION_AES128_GCM ||
+ conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM)
+ tfm = CRYPTO_GCM(ctx);
+ else
+ tfm = CRYPTO_CCM(ctx);
+
+ if (conn->cipher_type == SMB2_ENCRYPTION_AES256_CCM ||
+ conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM)
+ rc = crypto_aead_setkey(tfm, key, SMB3_GCM256_CRYPTKEY_SIZE);
+ else
+ rc = crypto_aead_setkey(tfm, key, SMB3_GCM128_CRYPTKEY_SIZE);
+ if (rc) {
+ pr_err("Failed to set aead key %d\n", rc);
+ goto free_ctx;
+ }
+
+ rc = crypto_aead_setauthsize(tfm, SMB2_SIGNATURE_SIZE);
+ if (rc) {
+ pr_err("Failed to set authsize %d\n", rc);
+ goto free_ctx;
+ }
+
+ req = aead_request_alloc(tfm, GFP_KERNEL);
+ if (!req) {
+ rc = -ENOMEM;
+ goto free_ctx;
+ }
+
+ if (!enc) {
+ memcpy(sign, &tr_hdr->Signature, SMB2_SIGNATURE_SIZE);
+ crypt_len += SMB2_SIGNATURE_SIZE;
+ }
+
+ sg = ksmbd_init_sg(iov, nvec, sign);
+ if (!sg) {
+ pr_err("Failed to init sg\n");
+ rc = -ENOMEM;
+ goto free_req;
+ }
+
+ iv_len = crypto_aead_ivsize(tfm);
+ iv = kzalloc(iv_len, GFP_KERNEL);
+ if (!iv) {
+ rc = -ENOMEM;
+ goto free_sg;
+ }
+
+ if (conn->cipher_type == SMB2_ENCRYPTION_AES128_GCM ||
+ conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM) {
+ memcpy(iv, (char *)tr_hdr->Nonce, SMB3_AES_GCM_NONCE);
+ } else {
+ iv[0] = 3;
+ memcpy(iv + 1, (char *)tr_hdr->Nonce, SMB3_AES_CCM_NONCE);
+ }
+
+ aead_request_set_crypt(req, sg, sg, crypt_len, iv);
+ aead_request_set_ad(req, assoc_data_len);
+ aead_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
+
+ if (enc)
+ rc = crypto_aead_encrypt(req);
+ else
+ rc = crypto_aead_decrypt(req);
+ if (rc)
+ goto free_iv;
+
+ if (enc)
+ memcpy(&tr_hdr->Signature, sign, SMB2_SIGNATURE_SIZE);
+
+free_iv:
+ kfree(iv);
+free_sg:
+ kfree(sg);
+free_req:
+ kfree(req);
+free_ctx:
+ ksmbd_release_crypto_ctx(ctx);
+ return rc;
+}