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samba-mirror/source3/lib/substitute.c
Günther Deschner 0b98400cc0 r8686: Revert %LOGONSERVER%-substitution. The substition is done on the client,
not on the server.

We now preserve this windows variable (important for vampired setups)
and correctly substitute only the "%L"s in strings like:

        "%LOGONSERVER% %L %lOgOnSeRvEr% %L".

Guenther
(This used to be commit dccf777f42)
2007-10-10 11:00:15 -05:00

823 lines
21 KiB
C

/*
Unix SMB/CIFS implementation.
string substitution functions
Copyright (C) Andrew Tridgell 1992-2000
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 2 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, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#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;
/* don't let anonymous logins override the name */
if (! *name)
return;
fstrcpy(tmp,name);
trim_char(tmp,' ',' ');
strlower_m(tmp);
alpha_strcpy(smb_user_name,tmp,SAFE_NETBIOS_CHARS,sizeof(smb_user_name)-1);
}
char* sub_get_smb_name( void )
{
return smb_user_name;
}
/*******************************************************************
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_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 %$(NAME) expand it as an environment variable.
Return the number of characters by which the pointer should be advanced.
Based on code by Branko Cibej <branko.cibej@hermes.si>
When this is called p points at the '%' character.
********************************************************************/
static size_t expand_env_var(char *p, int len)
{
fstring envname;
char *envval;
char *q, *r;
int copylen;
if (p[1] != '$')
return 1;
if (p[2] != '(')
return 2;
/*
* Look for the terminating ')'.
*/
if ((q = strchr_m(p,')')) == NULL) {
DEBUG(0,("expand_env_var: Unterminated environment variable [%s]\n", p));
return 2;
}
/*
* Extract the name from within the %$(NAME) string.
*/
r = p+3;
copylen = MIN((q-r),(sizeof(envname)-1));
strncpy(envname,r,copylen);
envname[copylen] = '\0';
if ((envval = getenv(envname)) == NULL) {
DEBUG(0,("expand_env_var: Environment variable [%s] not set\n", envname));
return 2;
}
/*
* Copy the full %$(NAME) into envname so it
* can be replaced.
*/
copylen = MIN((q+1-p),(sizeof(envname)-1));
strncpy(envname,p,copylen);
envname[copylen] = '\0';
string_sub(p,envname,envval,len);
return 0; /* Allow the environment contents to be parsed. */
}
/*******************************************************************
Given a pointer to a %$(NAME) in p and the whole string in str
expand it as an environment variable.
Return a new allocated and expanded string.
Based on code by Branko Cibej <branko.cibej@hermes.si>
When this is called p points at the '%' character.
May substitute multiple occurrencies of the same env var.
********************************************************************/
static char * realloc_expand_env_var(char *str, char *p)
{
char *envname;
char *envval;
char *q, *r;
int copylen;
if (p[0] != '%' || p[1] != '$' || 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 %$(NAME) string.
*/
r = p + 3;
copylen = q - r;
envname = (char *)SMB_MALLOC(copylen + 1 + 4); /* reserve space for use later add %$() chars */
if (envname == 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);
if (r == NULL) return NULL;
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)
{
static 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()) {
char *home_path_start;
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 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)
{
static 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 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, char *str,size_t len)
{
char *p, *s;
fstring pidstr;
struct passwd *pass;
const char *local_machine_name = get_local_machine_name();
for (s=str; (p=strchr_m(s, '%'));s=p) {
fstring tmp_str;
int l = (int)len - (int)(p-str);
if (l < 0)
l = 0;
switch (*(p+1)) {
case 'U' :
fstrcpy(tmp_str, smb_name);
strlower_m(tmp_str);
string_sub(p,"%U",tmp_str,l);
break;
case 'G' :
fstrcpy(tmp_str, smb_name);
if ((pass = Get_Pwnam(tmp_str))!=NULL) {
string_sub(p,"%G",gidtoname(pass->pw_gid),l);
} else {
p += 2;
}
break;
case 'D' :
fstrcpy(tmp_str, current_user_info.domain);
strupper_m(tmp_str);
string_sub(p,"%D", tmp_str,l);
break;
case 'I' :
string_sub(p,"%I", client_addr(),l);
break;
case 'i' :
string_sub(p,"%i", client_socket_addr(),l);
break;
case 'L' :
if (!StrnCaseCmp(p, "\%LOGONSERVER\%", 13)) {
p++;
break;
}
if (local_machine_name && *local_machine_name) {
string_sub_once(p, "%L", local_machine_name, l);
} else {
pstring temp_name;
pstrcpy(temp_name, global_myname());
strlower_m(temp_name);
string_sub_once(p, "%L", temp_name, l);
}
break;
case 'M' :
string_sub(p,"%M", client_name(),l);
break;
case 'R' :
string_sub(p,"%R", remote_proto,l);
break;
case 'T' :
string_sub(p,"%T", timestring(False),l);
break;
case 'a' :
string_sub(p,"%a", remote_arch,l);
break;
case 'd' :
slprintf(pidstr,sizeof(pidstr)-1, "%d",(int)sys_getpid());
string_sub(p,"%d", pidstr,l);
break;
case 'h' :
string_sub(p,"%h", myhostname(),l);
break;
case 'm' :
string_sub(p,"%m", get_remote_machine_name(),l);
break;
case 'v' :
string_sub(p,"%v", SAMBA_VERSION_STRING,l);
break;
case '$' :
p += expand_env_var(p,l);
break; /* Expand environment variables */
case '\0':
p++;
break; /* don't run off the end of the string */
default: p+=2;
break;
}
}
}
static void standard_sub_advanced(int snum, const char *user,
const char *connectpath, gid_t gid,
const char *smb_name, char *str, size_t len)
{
char *p, *s, *home;
for (s=str; (p=strchr_m(s, '%'));s=p) {
int l = (int)len - (int)(p-str);
if (l < 0)
l = 0;
switch (*(p+1)) {
case 'N' :
string_sub(p,"%N", automount_server(user),l);
break;
case 'H':
if ((home = get_user_home_dir(user)))
string_sub(p,"%H",home, l);
else
p += 2;
break;
case 'P':
string_sub(p,"%P", connectpath, l);
break;
case 'S':
if ( snum != -1 )
string_sub(p,"%S", lp_servicename(snum), l);
break;
case 'g':
string_sub(p,"%g", gidtoname(gid), l);
break;
case 'u':
string_sub(p,"%u", user, l);
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':
if ( snum != -1 )
string_sub(p,"%p", automount_path(lp_servicename(snum)), l);
break;
case '\0':
p++;
break; /* don't run off the end of the string */
default: p+=2;
break;
}
}
standard_sub_basic(smb_name, str, len);
}
/****************************************************************************
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 *str)
{
char *a, *t;
a = alloc_sub_basic(smb_name, str);
if (!a) return NULL;
t = talloc_strdup(mem_ctx, a);
SAFE_FREE(a);
return t;
}
char *alloc_sub_basic(const char *smb_name, const char *str)
{
char *b, *p, *s, *t, *r, *a_string;
fstring pidstr;
struct passwd *pass;
const char *local_machine_name = get_local_machine_name();
/* workaround to prevent a crash while lookinf 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_specified: Out of memory!\n"));
return NULL;
}
for (b = s = a_string; (p = strchr_m(s, '%')); s = a_string + (p - b)) {
r = NULL;
b = t = a_string;
switch (*(p+1)) {
case 'U' :
r = strdup_lower(smb_name);
if (r == NULL) goto error;
t = realloc_string_sub(t, "%U", r);
break;
case 'G' :
r = SMB_STRDUP(smb_name);
if (r == NULL) goto error;
if ((pass = Get_Pwnam(r))!=NULL) {
t = realloc_string_sub(t, "%G", gidtoname(pass->pw_gid));
}
break;
case 'D' :
r = strdup_upper(current_user_info.domain);
if (r == NULL) goto error;
t = realloc_string_sub(t, "%D", r);
break;
case 'I' :
t = realloc_string_sub(t, "%I", client_addr());
break;
case 'L' :
if (local_machine_name && *local_machine_name)
t = realloc_string_sub(t, "%L", local_machine_name);
else
t = realloc_string_sub(t, "%L", global_myname());
break;
case 'N':
t = realloc_string_sub(t, "%N", automount_server(smb_name));
break;
case 'M' :
t = realloc_string_sub(t, "%M", client_name());
break;
case 'R' :
t = realloc_string_sub(t, "%R", remote_proto);
break;
case 'T' :
t = realloc_string_sub(t, "%T", timestring(False));
break;
case 'a' :
t = realloc_string_sub(t, "%a", remote_arch);
break;
case 'd' :
slprintf(pidstr,sizeof(pidstr)-1, "%d",(int)sys_getpid());
t = realloc_string_sub(t, "%d", pidstr);
break;
case 'h' :
t = realloc_string_sub(t, "%h", myhostname());
break;
case 'm' :
t = realloc_string_sub(t, "%m", remote_machine);
break;
case 'v' :
t = realloc_string_sub(t, "%v", SAMBA_VERSION_STRING);
break;
case '$' :
t = realloc_expand_env_var(t, p); /* Expand environment variables */
break;
default:
break;
}
p++;
SAFE_FREE(r);
if (t == NULL) goto error;
a_string = t;
}
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, *t;
a = alloc_sub_specified(input_string, username, domain, uid, gid);
if (!a) return NULL;
t = talloc_strdup(mem_ctx, a);
SAFE_FREE(a);
return t;
}
char *alloc_sub_specified(const char *input_string,
const char *username,
const char *domain,
uid_t uid,
gid_t gid)
{
char *a_string, *ret_string;
char *b, *p, *s, *t;
a_string = SMB_STRDUP(input_string);
if (a_string == NULL) {
DEBUG(0, ("alloc_sub_specified: Out of memory!\n"));
return NULL;
}
for (b = s = a_string; (p = strchr_m(s, '%')); s = a_string + (p - b)) {
b = t = a_string;
switch (*(p+1)) {
case 'U' :
t = realloc_string_sub(t, "%U", username);
break;
case 'u' :
t = realloc_string_sub(t, "%u", username);
break;
case 'G' :
if (gid != -1) {
t = realloc_string_sub(t, "%G", gidtoname(gid));
} else {
t = realloc_string_sub(t, "%G", "NO_GROUP");
}
break;
case 'g' :
if (gid != -1) {
t = realloc_string_sub(t, "%g", gidtoname(gid));
} else {
t = realloc_string_sub(t, "%g", "NO_GROUP");
}
break;
case 'D' :
t = realloc_string_sub(t, "%D", domain);
break;
case 'N' :
t = realloc_string_sub(t, "%N", automount_server(username));
break;
default:
break;
}
p++;
if (t == NULL) {
SAFE_FREE(a_string);
return NULL;
}
a_string = t;
}
ret_string = alloc_sub_basic(username, a_string);
SAFE_FREE(a_string);
return ret_string;
}
char *talloc_sub_advanced(TALLOC_CTX *mem_ctx,
int snum,
const char *user,
const char *connectpath,
gid_t gid,
const char *smb_name,
const char *str)
{
char *a, *t;
a = alloc_sub_advanced(snum, user, connectpath, gid, smb_name, str);
if (!a) return NULL;
t = talloc_strdup(mem_ctx, a);
SAFE_FREE(a);
return t;
}
char *alloc_sub_advanced(int snum, const char *user,
const char *connectpath, gid_t gid,
const char *smb_name, const char *str)
{
char *a_string, *ret_string;
char *b, *p, *s, *t, *h;
a_string = SMB_STRDUP(str);
if (a_string == NULL) {
DEBUG(0, ("alloc_sub_specified: Out of memory!\n"));
return NULL;
}
for (b = s = a_string; (p = strchr_m(s, '%')); s = a_string + (p - b)) {
b = t = a_string;
switch (*(p+1)) {
case 'N' :
t = realloc_string_sub(t, "%N", automount_server(user));
break;
case 'H':
if ((h = get_user_home_dir(user)))
t = realloc_string_sub(t, "%H", h);
break;
case 'P':
t = realloc_string_sub(t, "%P", connectpath);
break;
case 'S':
t = realloc_string_sub(t, "%S", lp_servicename(snum));
break;
case 'g':
t = realloc_string_sub(t, "%g", gidtoname(gid));
break;
case 'u':
t = realloc_string_sub(t, "%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':
t = realloc_string_sub(t, "%p", automount_path(lp_servicename(snum)));
break;
default:
break;
}
p++;
if (t == NULL) {
SAFE_FREE(a_string);
return NULL;
}
a_string = t;
}
ret_string = alloc_sub_basic(smb_name, a_string);
SAFE_FREE(a_string);
return ret_string;
}
/****************************************************************************
Do some standard substitutions in a string.
****************************************************************************/
void standard_sub_conn(connection_struct *conn, char *str, size_t len)
{
standard_sub_advanced(SNUM(conn), conn->user, conn->connectpath,
conn->gid, smb_user_name, str, len);
}
char *talloc_sub_conn(TALLOC_CTX *mem_ctx, connection_struct *conn, const char *str)
{
return talloc_sub_advanced(mem_ctx, SNUM(conn), conn->user,
conn->connectpath, conn->gid,
smb_user_name, str);
}
char *alloc_sub_conn(connection_struct *conn, const char *str)
{
return alloc_sub_advanced(SNUM(conn), conn->user, conn->connectpath,
conn->gid, smb_user_name, str);
}
/****************************************************************************
Like standard_sub but by snum.
****************************************************************************/
void standard_sub_snum(int snum, char *str, size_t len)
{
static uid_t cached_uid = -1;
static fstring cached_user;
/* calling uidtoname() on every substitute would be too expensive, so
we cache the result here as nearly every call is for the same uid */
if (cached_uid != current_user.uid) {
fstrcpy(cached_user, uidtoname(current_user.uid));
cached_uid = current_user.uid;
}
standard_sub_advanced(snum, cached_user, "", current_user.gid,
smb_user_name, str, len);
}