/*
Unix SMB/CIFS implementation.
string substitution functions
Copyright (C) Andrew Tridgell 1992-2000
Copyright (C) Gerald Carter 2006
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"
extern struct current_user current_user;
fstring local_machine="";
fstring remote_arch="UNKNOWN";
userdom_struct current_user_info;
fstring remote_proto="UNKNOWN";
static fstring remote_machine;
static fstring smb_user_name;
/**
* Set the 'local' machine name
* @param local_name the name we are being called
* @param if this is the 'final' name for us, not be be changed again
*/
void set_local_machine_name(const char* local_name, bool perm)
{
static bool already_perm = False;
fstring tmp_local_machine;
fstrcpy(tmp_local_machine,local_name);
trim_char(tmp_local_machine,' ',' ');
/*
* Windows NT/2k uses "*SMBSERVER" and XP uses "*SMBSERV"
* arrggg!!!
*/
if ( strequal(tmp_local_machine, "*SMBSERVER") || strequal(tmp_local_machine, "*SMBSERV") ) {
fstrcpy( local_machine, client_socket_addr() );
return;
}
if (already_perm)
return;
already_perm = perm;
alpha_strcpy(local_machine,tmp_local_machine,SAFE_NETBIOS_CHARS,sizeof(local_machine)-1);
strlower_m(local_machine);
}
/**
* Set the 'remote' machine name
* @param remote_name the name our client wants to be called by
* @param if this is the 'final' name for them, not be be changed again
*/
void set_remote_machine_name(const char* remote_name, bool perm)
{
static bool already_perm = False;
fstring tmp_remote_machine;
if (already_perm)
return;
already_perm = perm;
fstrcpy(tmp_remote_machine,remote_name);
trim_char(tmp_remote_machine,' ',' ');
alpha_strcpy(remote_machine,tmp_remote_machine,SAFE_NETBIOS_CHARS,sizeof(remote_machine)-1);
strlower_m(remote_machine);
}
const char* get_remote_machine_name(void)
{
return remote_machine;
}
const char* get_local_machine_name(void)
{
if (!*local_machine) {
return global_myname();
}
return local_machine;
}
/*******************************************************************
Setup the string used by %U substitution.
********************************************************************/
void sub_set_smb_name(const char *name)
{
fstring tmp;
int len;
bool is_machine_account = False;
/* don't let anonymous logins override the name */
if (! *name)
return;
fstrcpy( tmp, name );
trim_char( tmp, ' ', ' ' );
strlower_m( tmp );
len = strlen( tmp );
if ( len == 0 )
return;
/* long story but here goes....we have to allow usernames
ending in '$' as they are valid machine account names.
So check for a machine account and re-add the '$'
at the end after the call to alpha_strcpy(). --jerry */
if ( tmp[len-1] == '$' )
is_machine_account = True;
alpha_strcpy( smb_user_name, tmp, SAFE_NETBIOS_CHARS, sizeof(smb_user_name)-1 );
if ( is_machine_account ) {
len = strlen( smb_user_name );
smb_user_name[len-1] = '$';
}
}
/*******************************************************************
Setup the strings used by substitutions. Called per packet. Ensure
%U name is set correctly also.
********************************************************************/
void set_current_user_info(const userdom_struct *pcui)
{
current_user_info = *pcui;
/* The following is safe as current_user_info.smb_name
* has already been sanitised in register_existing_vuid. */
fstrcpy(smb_user_name, current_user_info.smb_name);
}
/*******************************************************************
return the current active user name
*******************************************************************/
const char* get_current_username( void )
{
if ( current_user_info.smb_name[0] == '\0' )
return smb_user_name;
return current_user_info.smb_name;
}
/*******************************************************************
Given a pointer to a %$(NAME) in p and the whole string in str
expand it as an environment variable.
Return a new allocated and expanded string.
Based on code by Branko Cibej
When this is called p points at the '%' character.
May substitute multiple occurrencies of the same env var.
********************************************************************/
static char * realloc_expand_env_var(char *str, char *p)
{
char *envname;
char *envval;
char *q, *r;
int copylen;
if (p[0] != '%' || p[1] != '$' || p[2] != '(') {
return str;
}
/*
* Look for the terminating ')'.
*/
if ((q = strchr_m(p,')')) == NULL) {
DEBUG(0,("expand_env_var: Unterminated environment variable [%s]\n", p));
return str;
}
/*
* Extract the name from within the %$(NAME) string.
*/
r = p + 3;
copylen = q - r;
/* reserve space for use later add %$() chars */
if ( (envname = (char *)SMB_MALLOC(copylen + 1 + 4)) == NULL ) {
return NULL;
}
strncpy(envname,r,copylen);
envname[copylen] = '\0';
if ((envval = getenv(envname)) == NULL) {
DEBUG(0,("expand_env_var: Environment variable [%s] not set\n", envname));
SAFE_FREE(envname);
return str;
}
/*
* Copy the full %$(NAME) into envname so it
* can be replaced.
*/
copylen = q + 1 - p;
strncpy(envname,p,copylen);
envname[copylen] = '\0';
r = realloc_string_sub(str, envname, envval);
SAFE_FREE(envname);
return r;
}
/*******************************************************************
*******************************************************************/
static char *longvar_domainsid( void )
{
DOM_SID sid;
char *sid_string;
if ( !secrets_fetch_domain_sid( lp_workgroup(), &sid ) ) {
return NULL;
}
sid_string = SMB_STRDUP( sid_string_static( &sid ) );
if ( !sid_string ) {
DEBUG(0,("longvar_domainsid: failed to dup SID string!\n"));
}
return sid_string;
}
/*******************************************************************
*******************************************************************/
struct api_longvar {
const char *name;
char* (*fn)( void );
};
static struct api_longvar longvar_table[] = {
{ "DomainSID", longvar_domainsid },
{ NULL, NULL }
};
static char *get_longvar_val( const char *varname )
{
int i;
DEBUG(7,("get_longvar_val: expanding variable [%s]\n", varname));
for ( i=0; longvar_table[i].name; i++ ) {
if ( strequal( longvar_table[i].name, varname ) ) {
return longvar_table[i].fn();
}
}
return NULL;
}
/*******************************************************************
Expand the long smb.conf variable names given a pointer to a %(NAME).
Return the number of characters by which the pointer should be advanced.
When this is called p points at the '%' character.
********************************************************************/
static char *realloc_expand_longvar(char *str, char *p)
{
fstring varname;
char *value;
char *q, *r;
int copylen;
if ( p[0] != '%' || p[1] != '(' ) {
return str;
}
/* Look for the terminating ')'.*/
if ((q = strchr_m(p,')')) == NULL) {
DEBUG(0,("realloc_expand_longvar: Unterminated environment variable [%s]\n", p));
return str;
}
/* Extract the name from within the %(NAME) string.*/
r = p+2;
copylen = MIN( (q-r), (sizeof(varname)-1) );
strncpy(varname, r, copylen);
varname[copylen] = '\0';
if ((value = get_longvar_val(varname)) == NULL) {
DEBUG(0,("realloc_expand_longvar: Variable [%s] not set. Skipping\n", varname));
return str;
}
/* Copy the full %(NAME) into envname so it can be replaced.*/
copylen = MIN( (q+1-p),(sizeof(varname)-1) );
strncpy( varname, p, copylen );
varname[copylen] = '\0';
r = realloc_string_sub(str, varname, value);
SAFE_FREE( value );
/* skip over the %(varname) */
return r;
}
/*******************************************************************
Patch from jkf@soton.ac.uk
Added this to implement %p (NIS auto-map version of %H)
*******************************************************************/
static char *automount_path(const char *user_name)
{
pstring server_path;
/* use the passwd entry as the default */
/* this will be the default if WITH_AUTOMOUNT is not used or fails */
pstrcpy(server_path, get_user_home_dir(user_name));
#if (defined(HAVE_NETGROUP) && defined (WITH_AUTOMOUNT))
if (lp_nis_home_map()) {
const char *home_path_start;
const char *automount_value = automount_lookup(user_name);
if(strlen(automount_value) > 0) {
home_path_start = strchr_m(automount_value,':');
if (home_path_start != NULL) {
DEBUG(5, ("NIS lookup succeeded. Home path is: %s\n",
home_path_start?(home_path_start+1):""));
pstrcpy(server_path, home_path_start+1);
}
} else {
/* NIS key lookup failed: default to user home directory from password file */
DEBUG(5, ("NIS lookup failed. Using Home path from passwd file. Home path is: %s\n", server_path ));
}
}
#endif
DEBUG(4,("Home server path: %s\n", server_path));
return talloc_strdup(talloc_tos(), server_path);
}
/*******************************************************************
Patch from jkf@soton.ac.uk
This is Luke's original function with the NIS lookup code
moved out to a separate function.
*******************************************************************/
static const char *automount_server(const char *user_name)
{
pstring server_name;
const char *local_machine_name = get_local_machine_name();
/* use the local machine name as the default */
/* this will be the default if WITH_AUTOMOUNT is not used or fails */
if (local_machine_name && *local_machine_name)
pstrcpy(server_name, local_machine_name);
else
pstrcpy(server_name, global_myname());
#if (defined(HAVE_NETGROUP) && defined (WITH_AUTOMOUNT))
if (lp_nis_home_map()) {
int home_server_len;
char *automount_value = automount_lookup(user_name);
home_server_len = strcspn(automount_value,":");
DEBUG(5, ("NIS lookup succeeded. Home server length: %d\n",home_server_len));
if (home_server_len > sizeof(pstring))
home_server_len = sizeof(pstring);
strncpy(server_name, automount_value, home_server_len);
server_name[home_server_len] = '\0';
}
#endif
DEBUG(4,("Home server: %s\n", server_name));
return talloc_strdup(talloc_tos(), server_name);
}
/****************************************************************************
Do some standard substitutions in a string.
len is the length in bytes of the space allowed in string str. If zero means
don't allow expansions.
****************************************************************************/
void standard_sub_basic(const char *smb_name, const char *domain_name,
char *str, size_t len)
{
char *s;
if ( (s = alloc_sub_basic( smb_name, domain_name, str )) != NULL ) {
strncpy( str, s, len );
}
SAFE_FREE( s );
}
/****************************************************************************
Do some standard substitutions in a string.
This function will return an allocated string that have to be freed.
****************************************************************************/
char *talloc_sub_basic(TALLOC_CTX *mem_ctx, const char *smb_name,
const char *domain_name, const char *str)
{
char *a, *t;
if ( (a = alloc_sub_basic(smb_name, domain_name, str)) == NULL ) {
return NULL;
}
t = talloc_strdup(mem_ctx, a);
SAFE_FREE(a);
return t;
}
/****************************************************************************
****************************************************************************/
char *alloc_sub_basic(const char *smb_name, const char *domain_name,
const char *str)
{
char *b, *p, *s, *r, *a_string;
fstring pidstr, vnnstr;
struct passwd *pass;
char addr[INET6_ADDRSTRLEN];
const char *local_machine_name = get_local_machine_name();
/* workaround to prevent a crash while looking at bug #687 */
if (!str) {
DEBUG(0,("alloc_sub_basic: NULL source string! This should not happen\n"));
return NULL;
}
a_string = SMB_STRDUP(str);
if (a_string == NULL) {
DEBUG(0, ("alloc_sub_basic: Out of memory!\n"));
return NULL;
}
for (b = s = a_string; (p = strchr_m(s, '%')); s = a_string + (p - b)) {
r = NULL;
b = a_string;
switch (*(p+1)) {
case 'U' :
r = strdup_lower(smb_name);
if (r == NULL) {
goto error;
}
a_string = realloc_string_sub(a_string, "%U", r);
break;
case 'G' :
r = SMB_STRDUP(smb_name);
if (r == NULL) {
goto error;
}
if ((pass = Get_Pwnam(r))!=NULL) {
a_string = realloc_string_sub(a_string, "%G", gidtoname(pass->pw_gid));
}
break;
case 'D' :
r = strdup_upper(domain_name);
if (r == NULL) {
goto error;
}
a_string = realloc_string_sub(a_string, "%D", r);
break;
case 'I' :
a_string = realloc_string_sub(a_string, "%I", client_addr(addr));
break;
case 'i':
a_string = realloc_string_sub( a_string, "%i", client_socket_addr() );
break;
case 'L' :
if ( StrnCaseCmp(p, "%LOGONSERVER%", strlen("%LOGONSERVER%")) == 0 ) {
break;
}
if (local_machine_name && *local_machine_name) {
a_string = realloc_string_sub(a_string, "%L", local_machine_name);
} else {
a_string = realloc_string_sub(a_string, "%L", global_myname());
}
break;
case 'N':
a_string = realloc_string_sub(a_string, "%N", automount_server(smb_name));
break;
case 'M' :
a_string = realloc_string_sub(a_string, "%M", client_name());
break;
case 'R' :
a_string = realloc_string_sub(a_string, "%R", remote_proto);
break;
case 'T' :
a_string = realloc_string_sub(a_string, "%T", current_timestring(False));
break;
case 'a' :
a_string = realloc_string_sub(a_string, "%a", remote_arch);
break;
case 'd' :
slprintf(pidstr,sizeof(pidstr)-1, "%d",(int)sys_getpid());
a_string = realloc_string_sub(a_string, "%d", pidstr);
break;
case 'h' :
a_string = realloc_string_sub(a_string, "%h", myhostname());
break;
case 'm' :
a_string = realloc_string_sub(a_string, "%m", remote_machine);
break;
case 'v' :
a_string = realloc_string_sub(a_string, "%v", SAMBA_VERSION_STRING);
break;
case 'w' :
a_string = realloc_string_sub(a_string, "%w", lp_winbind_separator());
break;
case '$' :
a_string = realloc_expand_env_var(a_string, p); /* Expand environment variables */
break;
case '(':
a_string = realloc_expand_longvar( a_string, p );
break;
case 'V' :
slprintf(vnnstr,sizeof(vnnstr)-1, "%u", get_my_vnn());
a_string = realloc_string_sub(a_string, "%V", vnnstr);
break;
default:
break;
}
p++;
SAFE_FREE(r);
if ( !a_string ) {
return NULL;
}
}
return a_string;
error:
SAFE_FREE(a_string);
return NULL;
}
/****************************************************************************
Do some specific substitutions in a string.
This function will return an allocated string that have to be freed.
****************************************************************************/
char *talloc_sub_specified(TALLOC_CTX *mem_ctx,
const char *input_string,
const char *username,
const char *domain,
uid_t uid,
gid_t gid)
{
char *a_string;
char *ret_string = NULL;
char *b, *p, *s;
TALLOC_CTX *tmp_ctx;
if (!(tmp_ctx = talloc_new(mem_ctx))) {
DEBUG(0, ("talloc_new failed\n"));
return NULL;
}
a_string = talloc_strdup(tmp_ctx, input_string);
if (a_string == NULL) {
DEBUG(0, ("talloc_sub_specified: Out of memory!\n"));
goto done;
}
for (b = s = a_string; (p = strchr_m(s, '%')); s = a_string + (p - b)) {
b = a_string;
switch (*(p+1)) {
case 'U' :
a_string = talloc_string_sub(
tmp_ctx, a_string, "%U", username);
break;
case 'u' :
a_string = talloc_string_sub(
tmp_ctx, a_string, "%u", username);
break;
case 'G' :
if (gid != -1) {
a_string = talloc_string_sub(
tmp_ctx, a_string, "%G",
gidtoname(gid));
} else {
a_string = talloc_string_sub(
tmp_ctx, a_string,
"%G", "NO_GROUP");
}
break;
case 'g' :
if (gid != -1) {
a_string = talloc_string_sub(
tmp_ctx, a_string, "%g",
gidtoname(gid));
} else {
a_string = talloc_string_sub(
tmp_ctx, a_string, "%g", "NO_GROUP");
}
break;
case 'D' :
a_string = talloc_string_sub(tmp_ctx, a_string,
"%D", domain);
break;
case 'N' :
a_string = talloc_string_sub(
tmp_ctx, a_string, "%N",
automount_server(username));
break;
default:
break;
}
p++;
if (a_string == NULL) {
goto done;
}
}
/* Watch out, using "mem_ctx" here, so all intermediate stuff goes
* away with the TALLOC_FREE(tmp_ctx) further down. */
ret_string = talloc_sub_basic(mem_ctx, username, domain, a_string);
done:
TALLOC_FREE(tmp_ctx);
return ret_string;
}
/****************************************************************************
****************************************************************************/
static char *alloc_sub_advanced(const char *servicename, const char *user,
const char *connectpath, gid_t gid,
const char *smb_name, const char *domain_name,
const char *str)
{
char *a_string, *ret_string;
char *b, *p, *s, *h;
a_string = SMB_STRDUP(str);
if (a_string == NULL) {
DEBUG(0, ("alloc_sub_advanced: Out of memory!\n"));
return NULL;
}
for (b = s = a_string; (p = strchr_m(s, '%')); s = a_string + (p - b)) {
b = a_string;
switch (*(p+1)) {
case 'N' :
a_string = realloc_string_sub(a_string, "%N", automount_server(user));
break;
case 'H':
if ((h = get_user_home_dir(user)))
a_string = realloc_string_sub(a_string, "%H", h);
break;
case 'P':
a_string = realloc_string_sub(a_string, "%P", connectpath);
break;
case 'S':
a_string = realloc_string_sub(a_string, "%S", servicename);
break;
case 'g':
a_string = realloc_string_sub(a_string, "%g", gidtoname(gid));
break;
case 'u':
a_string = realloc_string_sub(a_string, "%u", user);
break;
/* Patch from jkf@soton.ac.uk Left the %N (NIS
* server name) in standard_sub_basic as it is
* a feature for logon servers, hence uses the
* username. The %p (NIS server path) code is
* here as it is used instead of the default
* "path =" string in [homes] and so needs the
* service name, not the username. */
case 'p':
a_string = realloc_string_sub(a_string, "%p",
automount_path(servicename));
break;
default:
break;
}
p++;
if (a_string == NULL) {
return NULL;
}
}
ret_string = alloc_sub_basic(smb_name, domain_name, a_string);
SAFE_FREE(a_string);
return ret_string;
}
/*
* This obviously is inefficient and needs to be merged into
* alloc_sub_advanced...
*/
char *talloc_sub_advanced(TALLOC_CTX *mem_ctx,
const char *servicename, const char *user,
const char *connectpath, gid_t gid,
const char *smb_name, const char *domain_name,
const char *str)
{
char *a, *t;
if (!(a = alloc_sub_advanced(servicename, user, connectpath, gid,
smb_name, domain_name, str))) {
return NULL;
}
t = talloc_strdup(mem_ctx, a);
SAFE_FREE(a);
return t;
}
void standard_sub_advanced(const char *servicename, const char *user,
const char *connectpath, gid_t gid,
const char *smb_name, const char *domain_name,
char *str, size_t len)
{
char *s;
s = alloc_sub_advanced(servicename, user, connectpath,
gid, smb_name, domain_name, str);
if ( s ) {
strncpy( str, s, len );
SAFE_FREE( s );
}
}
/****************************************************************************
* Do some standard substitutions in a string.
* ****************************************************************************/
void standard_sub_conn(connection_struct *conn, char *str, size_t len)
{
char *s;
s = alloc_sub_advanced(lp_servicename(SNUM(conn)), conn->user, conn->connectpath,
conn->gid, smb_user_name, "", str);
if ( s ) {
strncpy( str, s, len );
SAFE_FREE( s );
}
}