From 439086099ad97a49c93102af1e6edafabea64b6f Mon Sep 17 00:00:00 2001 From: Volker Lendecke Date: Mon, 22 Sep 2008 19:29:05 +0200 Subject: Add netlogond auth method This authenticates against a local running samba4 using SamLogonEx. We retrieve the machine password using samba4's mymachinepwd script and store the schannel key for re-use in secrets.tdb. --- source3/auth/auth_netlogond.c | 321 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 321 insertions(+) create mode 100644 source3/auth/auth_netlogond.c (limited to 'source3/auth') diff --git a/source3/auth/auth_netlogond.c b/source3/auth/auth_netlogond.c new file mode 100644 index 0000000000..a57f3b74a3 --- /dev/null +++ b/source3/auth/auth_netlogond.c @@ -0,0 +1,321 @@ +/* + Unix SMB/CIFS implementation. + Authenticate against a netlogon pipe listening on a unix domain socket + Copyright (C) Volker Lendecke 2008 + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +#include "includes.h" + +#undef DBGC_CLASS +#define DBGC_CLASS DBGC_AUTH + +static NTSTATUS netlogond_validate(TALLOC_CTX *mem_ctx, + const struct auth_context *auth_context, + const char *ncalrpc_sockname, + uint8_t schannel_key[16], + const auth_usersupplied_info *user_info, + struct netr_SamInfo3 **pinfo3, + NTSTATUS *schannel_bind_result) +{ + struct rpc_pipe_client *p; + struct cli_pipe_auth_data *auth; + struct netr_SamInfo3 *info3 = NULL; + NTSTATUS status; + + *schannel_bind_result = NT_STATUS_OK; + + status = rpc_pipe_open_ncalrpc(talloc_tos(), ncalrpc_sockname, + &ndr_table_netlogon.syntax_id, &p); + if (!NT_STATUS_IS_OK(status)) { + DEBUG(10, ("rpc_pipe_open_ncalrpc failed: %s\n", + nt_errstr(status))); + return status; + } + + status = rpccli_schannel_bind_data(p, lp_workgroup(), + PIPE_AUTH_LEVEL_PRIVACY, + schannel_key, &auth); + if (!NT_STATUS_IS_OK(status)) { + DEBUG(10, ("rpccli_schannel_bind_data failed: %s\n", + nt_errstr(status))); + TALLOC_FREE(p); + return status; + } + + status = rpc_pipe_bind(p, auth); + if (!NT_STATUS_IS_OK(status)) { + DEBUG(10, ("rpc_pipe_bind failed: %s\n", nt_errstr(status))); + TALLOC_FREE(p); + *schannel_bind_result = status; + return status; + } + + /* + * We have to fake a struct dcinfo, so that + * rpccli_netlogon_sam_network_logon_ex can decrypt the session keys. + */ + + p->dc = talloc(p, struct dcinfo); + if (p->dc == NULL) { + DEBUG(0, ("talloc failed\n")); + TALLOC_FREE(p); + return NT_STATUS_NO_MEMORY; + } + + memcpy(p->dc->sess_key, schannel_key, 16); + + status = rpccli_netlogon_sam_network_logon_ex( + p, p, + user_info->logon_parameters,/* flags such as 'allow + * workstation logon' */ + global_myname(), /* server name */ + user_info->smb_name, /* user name logging on. */ + user_info->client_domain, /* domain name */ + user_info->wksta_name, /* workstation name */ + (uchar *)auth_context->challenge.data, /* 8 byte challenge. */ + user_info->lm_resp, /* lanman 24 byte response */ + user_info->nt_resp, /* nt 24 byte response */ + &info3); /* info3 out */ + + DEBUG(10, ("rpccli_netlogon_sam_network_logon_ex returned %s\n", + nt_errstr(status))); + + if (!NT_STATUS_IS_OK(status)) { + TALLOC_FREE(p); + return status; + } + + *pinfo3 = talloc_move(mem_ctx, &info3); + + TALLOC_FREE(p); + return NT_STATUS_OK; +} + +static char *mymachinepw(TALLOC_CTX *mem_ctx) +{ + fstring pwd; + const char *script; + char *to_free = NULL; + ssize_t nread; + int ret, fd; + + script = lp_parm_const_string( + GLOBAL_SECTION_SNUM, "auth_netlogond", "machinepwscript", + NULL); + + if (script == NULL) { + to_free = talloc_asprintf(talloc_tos(), "%s/%s", + get_dyn_SBINDIR(), "mymachinepw"); + script = to_free; + } + if (script == NULL) { + return NULL; + } + + ret = smbrun(script, &fd); + DEBUG(ret ? 0 : 3, ("mymachinepw: Running the command `%s' gave %d\n", + script, ret)); + TALLOC_FREE(to_free); + + if (ret != 0) { + return NULL; + } + + pwd[sizeof(pwd)-1] = '\0'; + + nread = read(fd, pwd, sizeof(pwd)-1); + close(fd); + + if (nread <= 0) { + DEBUG(3, ("mymachinepwd: Could not read password\n")); + return NULL; + } + + DEBUG(0, ("pwd: %d [%s]\n", (int)nread, pwd)); + + if (pwd[nread-1] == '\n') { + pwd[nread-1] = '\0'; + } + + return talloc_strdup(mem_ctx, pwd); +} + +static NTSTATUS check_netlogond_security(const struct auth_context *auth_context, + void *my_private_data, + TALLOC_CTX *mem_ctx, + const auth_usersupplied_info *user_info, + auth_serversupplied_info **server_info) +{ + TALLOC_CTX *frame = talloc_stackframe(); + struct netr_SamInfo3 *info3 = NULL; + struct rpc_pipe_client *p; + struct cli_pipe_auth_data *auth; + uint32_t neg_flags = NETLOGON_NEG_AUTH2_ADS_FLAGS; + char *plaintext_machinepw; + uint8_t machine_password[16]; + uint8_t schannel_key[16]; + NTSTATUS schannel_bind_result, status; + struct named_mutex *mutex; + const char *ncalrpcsock; + + ncalrpcsock = lp_parm_const_string( + GLOBAL_SECTION_SNUM, "auth_netlogond", "socket", NULL); + + if (ncalrpcsock == NULL) { + ncalrpcsock = talloc_asprintf(talloc_tos(), "%s/%s", + get_dyn_NCALRPCDIR(), "DEFAULT"); + } + + if (ncalrpcsock == NULL) { + status = NT_STATUS_NO_MEMORY; + goto done; + } + + if (!secrets_fetch_local_schannel_key(schannel_key)) { + goto new_key; + } + + status = netlogond_validate(talloc_tos(), auth_context, ncalrpcsock, + schannel_key, user_info, &info3, + &schannel_bind_result); + + DEBUG(10, ("netlogond_validate returned %s\n", nt_errstr(status))); + + if (NT_STATUS_IS_OK(status)) { + goto okay; + } + + if (NT_STATUS_IS_OK(schannel_bind_result)) { + /* + * This is a real failure from the DC + */ + goto done; + } + + new_key: + + mutex = grab_named_mutex(talloc_tos(), "LOCAL_SCHANNEL_KEY", 60); + if (mutex == NULL) { + DEBUG(10, ("Could not get mutex LOCAL_SCHANNEL_KEY\n")); + status = NT_STATUS_ACCESS_DENIED; + goto done; + } + + DEBUG(10, ("schannel bind failed, setting up new key\n")); + + status = rpc_pipe_open_ncalrpc(talloc_tos(), ncalrpcsock, + &ndr_table_netlogon.syntax_id, &p); + + if (!NT_STATUS_IS_OK(status)) { + DEBUG(10, ("rpc_pipe_open_ncalrpc failed: %s\n", + nt_errstr(status))); + goto done; + } + + status = rpccli_anon_bind_data(p, &auth); + if (!NT_STATUS_IS_OK(status)) { + DEBUG(10, ("rpccli_anon_bind_data failed: %s\n", + nt_errstr(status))); + goto done; + } + + status = rpc_pipe_bind(p, auth); + if (!NT_STATUS_IS_OK(status)) { + DEBUG(10, ("rpc_pipe_bind failed: %s\n", nt_errstr(status))); + goto done; + } + + TALLOC_FREE(auth); + + plaintext_machinepw = mymachinepw(talloc_tos()); + if (plaintext_machinepw == NULL) { + status = NT_STATUS_NO_MEMORY; + goto done; + } + + E_md4hash(plaintext_machinepw, machine_password); + + TALLOC_FREE(plaintext_machinepw); + + status = rpccli_netlogon_setup_creds( + p, global_myname(), lp_workgroup(), global_myname(), + global_myname(), machine_password, SEC_CHAN_BDC, &neg_flags); + + if (!NT_STATUS_IS_OK(status)) { + DEBUG(10, ("rpccli_netlogon_setup_creds failed: %s\n", + nt_errstr(status))); + goto done; + } + + memcpy(schannel_key, p->dc->sess_key, 16); + secrets_store_local_schannel_key(schannel_key); + + TALLOC_FREE(p); + + /* + * Retry the authentication with the mutex held. This way nobody else + * can step on our toes. + */ + + status = netlogond_validate(talloc_tos(), auth_context, ncalrpcsock, + schannel_key, user_info, &info3, + &schannel_bind_result); + + DEBUG(10, ("netlogond_validate returned %s\n", nt_errstr(status))); + + if (!NT_STATUS_IS_OK(status)) { + goto done; + } + + okay: + + status = make_server_info_info3(mem_ctx, user_info->smb_name, + user_info->domain, server_info, + info3); + if (!NT_STATUS_IS_OK(status)) { + DEBUG(10, ("make_server_info_info3 failed: %s\n", + nt_errstr(status))); + TALLOC_FREE(frame); + return status; + } + + status = NT_STATUS_OK; + + done: + TALLOC_FREE(frame); + return status; +} + +/* module initialisation */ +static NTSTATUS auth_init_netlogond(struct auth_context *auth_context, + const char *param, + auth_methods **auth_method) +{ + if (!make_auth_methods(auth_context, auth_method)) { + return NT_STATUS_NO_MEMORY; + } + + (*auth_method)->name = "netlogond"; + (*auth_method)->auth = check_netlogond_security; + return NT_STATUS_OK; +} + +NTSTATUS auth_netlogond_init(void) +{ + smb_register_auth(AUTH_INTERFACE_VERSION, "netlogond", + auth_init_netlogond); + return NT_STATUS_OK; +} -- cgit