diff options
Diffstat (limited to 'fs/smb/server/auth.c')
| -rw-r--r-- | fs/smb/server/auth.c | 1216 |
1 files changed, 1216 insertions, 0 deletions
diff --git a/fs/smb/server/auth.c b/fs/smb/server/auth.c new file mode 100644 index 0000000000..229a652787 --- /dev/null +++ b/fs/smb/server/auth.c @@ -0,0 +1,1216 @@ +// 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; + + if (sess_key_len > CIFS_KEY_SIZE) + 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, total_entries = 0, sg_idx = 0; + + if (!nvec) + return NULL; + + nr_entries = kcalloc(nvec, sizeof(int), GFP_KERNEL); + if (!nr_entries) + 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) { + kfree(nr_entries); + 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); + kfree(nr_entries); + 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; +} |