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/*
* Unix SMB/Netbios implementation.
* Utility for managing share permissions
*
* Copyright (C) Tim Potter 2000
* Copyright (C) Jeremy Allison 2000
* Copyright (C) Jelmer Vernooij 2003
* Copyright (C) Gerald (Jerry) Carter 2005.
*
* 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 <http://www.gnu.org/licenses/>.
*/
#include "includes.h"
#include "popt_common.h"
#include "../libcli/security/security.h"
static TALLOC_CTX *ctx;
enum acl_mode { SMB_ACL_DELETE,
SMB_ACL_MODIFY,
SMB_ACL_ADD,
SMB_ACL_SET,
SMB_SD_DELETE,
SMB_ACL_VIEW };
struct perm_value {
const char *perm;
uint32 mask;
};
/* These values discovered by inspection */
static const struct perm_value special_values[] = {
{ "R", SEC_RIGHTS_FILE_READ },
{ "W", SEC_RIGHTS_FILE_WRITE },
{ "X", SEC_RIGHTS_FILE_EXECUTE },
{ "D", SEC_STD_DELETE },
{ "P", SEC_STD_WRITE_DAC },
{ "O", SEC_STD_WRITE_OWNER },
{ NULL, 0 },
};
#define SEC_RIGHTS_DIR_CHANGE ( SEC_RIGHTS_DIR_READ|SEC_STD_DELETE|\
SEC_RIGHTS_DIR_WRITE|SEC_DIR_TRAVERSE )
static const struct perm_value standard_values[] = {
{ "READ", SEC_RIGHTS_DIR_READ|SEC_DIR_TRAVERSE },
{ "CHANGE", SEC_RIGHTS_DIR_CHANGE },
{ "FULL", SEC_RIGHTS_DIR_ALL },
{ NULL, 0 },
};
/********************************************************************
print an ACE on a FILE
********************************************************************/
static void print_ace(FILE *f, struct security_ace *ace)
{
const struct perm_value *v;
int do_print = 0;
uint32 got_mask;
fprintf(f, "%s:", sid_string_tos(&ace->trustee));
/* Ace type */
if (ace->type == SEC_ACE_TYPE_ACCESS_ALLOWED) {
fprintf(f, "ALLOWED");
} else if (ace->type == SEC_ACE_TYPE_ACCESS_DENIED) {
fprintf(f, "DENIED");
} else {
fprintf(f, "%d", ace->type);
}
/* Not sure what flags can be set in a file ACL */
fprintf(f, "/%d/", ace->flags);
/* Standard permissions */
for (v = standard_values; v->perm; v++) {
if (ace->access_mask == v->mask) {
fprintf(f, "%s", v->perm);
return;
}
}
/* Special permissions. Print out a hex value if we have
leftover bits in the mask. */
got_mask = ace->access_mask;
again:
for (v = special_values; v->perm; v++) {
if ((ace->access_mask & v->mask) == v->mask) {
if (do_print) {
fprintf(f, "%s", v->perm);
}
got_mask &= ~v->mask;
}
}
if (!do_print) {
if (got_mask != 0) {
fprintf(f, "0x%08x", ace->access_mask);
} else {
do_print = 1;
goto again;
}
}
}
/********************************************************************
print an ascii version of a security descriptor on a FILE handle
********************************************************************/
static void sec_desc_print(FILE *f, struct security_descriptor *sd)
{
uint32 i;
fprintf(f, "REVISION:%d\n", sd->revision);
/* Print owner and group sid */
fprintf(f, "OWNER:%s\n", sid_string_tos(sd->owner_sid));
fprintf(f, "GROUP:%s\n", sid_string_tos(sd->group_sid));
/* Print aces */
for (i = 0; sd->dacl && i < sd->dacl->num_aces; i++) {
struct security_ace *ace = &sd->dacl->aces[i];
fprintf(f, "ACL:");
print_ace(f, ace);
fprintf(f, "\n");
}
}
/********************************************************************
parse an ACE in the same format as print_ace()
********************************************************************/
static bool parse_ace(struct security_ace *ace, const char *orig_str)
{
char *p;
const char *cp;
char *tok;
unsigned int atype = 0;
unsigned int aflags = 0;
unsigned int amask = 0;
struct dom_sid sid;
uint32_t mask;
const struct perm_value *v;
char *str = SMB_STRDUP(orig_str);
TALLOC_CTX *frame = talloc_stackframe();
if (!str) {
TALLOC_FREE(frame);
return False;
}
ZERO_STRUCTP(ace);
p = strchr_m(str,':');
if (!p) {
fprintf(stderr, "ACE '%s': missing ':'.\n", orig_str);
SAFE_FREE(str);
TALLOC_FREE(frame);
return False;
}
*p = '\0';
p++;
/* Try to parse numeric form */
if (sscanf(p, "%i/%i/%i", &atype, &aflags, &amask) == 3 &&
string_to_sid(&sid, str)) {
goto done;
}
/* Try to parse text form */
if (!string_to_sid(&sid, str)) {
fprintf(stderr, "ACE '%s': failed to convert '%s' to SID\n",
orig_str, str);
SAFE_FREE(str);
TALLOC_FREE(frame);
return False;
}
cp = p;
if (!next_token_talloc(frame, &cp, &tok, "/")) {
fprintf(stderr, "ACE '%s': failed to find '/' character.\n",
orig_str);
SAFE_FREE(str);
TALLOC_FREE(frame);
return False;
}
if (strncmp(tok, "ALLOWED", strlen("ALLOWED")) == 0) {
atype = SEC_ACE_TYPE_ACCESS_ALLOWED;
} else if (strncmp(tok, "DENIED", strlen("DENIED")) == 0) {
atype = SEC_ACE_TYPE_ACCESS_DENIED;
} else {
fprintf(stderr, "ACE '%s': missing 'ALLOWED' or 'DENIED' "
"entry at '%s'\n", orig_str, tok);
SAFE_FREE(str);
TALLOC_FREE(frame);
return False;
}
/* Only numeric form accepted for flags at present */
/* no flags on share permissions */
if (!(next_token_talloc(frame, &cp, &tok, "/") &&
sscanf(tok, "%i", &aflags) && aflags == 0)) {
fprintf(stderr, "ACE '%s': bad integer flags entry at '%s'\n",
orig_str, tok);
SAFE_FREE(str);
TALLOC_FREE(frame);
return False;
}
if (!next_token_talloc(frame, &cp, &tok, "/")) {
fprintf(stderr, "ACE '%s': missing / at '%s'\n",
orig_str, tok);
SAFE_FREE(str);
TALLOC_FREE(frame);
return False;
}
if (strncmp(tok, "0x", 2) == 0) {
if (sscanf(tok, "%i", &amask) != 1) {
fprintf(stderr, "ACE '%s': bad hex number at '%s'\n",
orig_str, tok);
TALLOC_FREE(frame);
SAFE_FREE(str);
return False;
}
goto done;
}
for (v = standard_values; v->perm; v++) {
if (strcmp(tok, v->perm) == 0) {
amask = v->mask;
goto done;
}
}
p = tok;
while(*p) {
bool found = False;
for (v = special_values; v->perm; v++) {
if (v->perm[0] == *p) {
amask |= v->mask;
found = True;
}
}
if (!found) {
fprintf(stderr, "ACE '%s': bad permission value at "
"'%s'\n", orig_str, p);
TALLOC_FREE(frame);
SAFE_FREE(str);
return False;
}
p++;
}
if (*p) {
TALLOC_FREE(frame);
SAFE_FREE(str);
return False;
}
done:
mask = amask;
init_sec_ace(ace, &sid, atype, mask, aflags);
SAFE_FREE(str);
TALLOC_FREE(frame);
return True;
}
/********************************************************************
********************************************************************/
static struct security_descriptor* parse_acl_string(TALLOC_CTX *mem_ctx, const char *szACL, size_t *sd_size )
{
struct security_descriptor *sd = NULL;
struct security_ace *ace;
struct security_acl *theacl;
int num_ace;
const char *pacl;
int i;
if ( !szACL )
return NULL;
pacl = szACL;
num_ace = count_chars( pacl, ',' ) + 1;
if ( !(ace = TALLOC_ZERO_ARRAY( mem_ctx, struct security_ace, num_ace )) )
return NULL;
for ( i=0; i<num_ace; i++ ) {
char *end_acl = strchr_m( pacl, ',' );
fstring acl_string;
strncpy( acl_string, pacl, MIN( PTR_DIFF( end_acl, pacl ), sizeof(fstring)-1) );
acl_string[MIN( PTR_DIFF( end_acl, pacl ), sizeof(fstring)-1)] = '\0';
if ( !parse_ace( &ace[i], acl_string ) )
return NULL;
pacl = end_acl;
pacl++;
}
if ( !(theacl = make_sec_acl( mem_ctx, NT4_ACL_REVISION, num_ace, ace )) )
return NULL;
sd = make_sec_desc( mem_ctx, SD_REVISION, SEC_DESC_SELF_RELATIVE,
NULL, NULL, NULL, theacl, sd_size);
return sd;
}
/* add an ACE to a list of ACEs in a struct security_acl */
static bool add_ace(TALLOC_CTX *mem_ctx, struct security_acl **the_acl, struct security_ace *ace)
{
struct security_acl *new_ace;
struct security_ace *aces;
if (! *the_acl) {
return (((*the_acl) = make_sec_acl(mem_ctx, 3, 1, ace)) != NULL);
}
if (!(aces = SMB_CALLOC_ARRAY(struct security_ace, 1+(*the_acl)->num_aces))) {
return False;
}
memcpy(aces, (*the_acl)->aces, (*the_acl)->num_aces * sizeof(struct
security_ace));
memcpy(aces+(*the_acl)->num_aces, ace, sizeof(struct security_ace));
new_ace = make_sec_acl(mem_ctx,(*the_acl)->revision,1+(*the_acl)->num_aces, aces);
SAFE_FREE(aces);
(*the_acl) = new_ace;
return True;
}
/* The MSDN is contradictory over the ordering of ACE entries in an ACL.
However NT4 gives a "The information may have been modified by a
computer running Windows NT 5.0" if denied ACEs do not appear before
allowed ACEs. */
static int ace_compare(struct security_ace *ace1, struct security_ace *ace2)
{
if (sec_ace_equal(ace1, ace2))
return 0;
if (ace1->type != ace2->type)
return ace2->type - ace1->type;
if (dom_sid_compare(&ace1->trustee, &ace2->trustee))
return dom_sid_compare(&ace1->trustee, &ace2->trustee);
if (ace1->flags != ace2->flags)
return ace1->flags - ace2->flags;
if (ace1->access_mask != ace2->access_mask)
return ace1->access_mask - ace2->access_mask;
if (ace1->size != ace2->size)
return ace1->size - ace2->size;
return memcmp(ace1, ace2, sizeof(struct security_ace));
}
static void sort_acl(struct security_acl *the_acl)
{
uint32 i;
if (!the_acl) return;
TYPESAFE_QSORT(the_acl->aces, the_acl->num_aces, ace_compare);
for (i=1;i<the_acl->num_aces;) {
if (sec_ace_equal(&the_acl->aces[i-1], &the_acl->aces[i])) {
int j;
for (j=i; j<the_acl->num_aces-1; j++) {
the_acl->aces[j] = the_acl->aces[j+1];
}
the_acl->num_aces--;
} else {
i++;
}
}
}
static int change_share_sec(TALLOC_CTX *mem_ctx, const char *sharename, char *the_acl, enum acl_mode mode)
{
struct security_descriptor *sd = NULL;
struct security_descriptor *old = NULL;
size_t sd_size = 0;
uint32 i, j;
if (mode != SMB_ACL_SET && mode != SMB_SD_DELETE) {
if (!(old = get_share_security( mem_ctx, sharename, &sd_size )) ) {
fprintf(stderr, "Unable to retrieve permissions for share "
"[%s]\n", sharename);
return -1;
}
}
if ( (mode != SMB_ACL_VIEW && mode != SMB_SD_DELETE) &&
!(sd = parse_acl_string(mem_ctx, the_acl, &sd_size )) ) {
fprintf( stderr, "Failed to parse acl\n");
return -1;
}
switch (mode) {
case SMB_ACL_VIEW:
sec_desc_print( stdout, old);
return 0;
case SMB_ACL_DELETE:
for (i=0;sd->dacl && i<sd->dacl->num_aces;i++) {
bool found = False;
for (j=0;old->dacl && j<old->dacl->num_aces;j++) {
if (sec_ace_equal(&sd->dacl->aces[i], &old->dacl->aces[j])) {
uint32 k;
for (k=j; k<old->dacl->num_aces-1;k++) {
old->dacl->aces[k] = old->dacl->aces[k+1];
}
old->dacl->num_aces--;
found = True;
break;
}
}
if (!found) {
printf("ACL for ACE:");
print_ace(stdout, &sd->dacl->aces[i]);
printf(" not found\n");
}
}
break;
case SMB_ACL_MODIFY:
for (i=0;sd->dacl && i<sd->dacl->num_aces;i++) {
bool found = False;
for (j=0;old->dacl && j<old->dacl->num_aces;j++) {
if (dom_sid_equal(&sd->dacl->aces[i].trustee,
&old->dacl->aces[j].trustee)) {
old->dacl->aces[j] = sd->dacl->aces[i];
found = True;
}
}
if (!found) {
printf("ACL for SID %s not found\n",
sid_string_tos(&sd->dacl->aces[i].trustee));
}
}
if (sd->owner_sid) {
old->owner_sid = sd->owner_sid;
}
if (sd->group_sid) {
old->group_sid = sd->group_sid;
}
break;
case SMB_ACL_ADD:
for (i=0;sd->dacl && i<sd->dacl->num_aces;i++) {
add_ace(mem_ctx, &old->dacl, &sd->dacl->aces[i]);
}
break;
case SMB_ACL_SET:
old = sd;
break;
case SMB_SD_DELETE:
if (!delete_share_security(sharename)) {
fprintf( stderr, "Failed to delete security descriptor for "
"share [%s]\n", sharename );
return -1;
}
return 0;
}
/* Denied ACE entries must come before allowed ones */
sort_acl(old->dacl);
if ( !set_share_security( sharename, old ) ) {
fprintf( stderr, "Failed to store acl for share [%s]\n", sharename );
return 2;
}
return 0;
}
/********************************************************************
main program
********************************************************************/
int main(int argc, const char *argv[])
{
int opt;
int retval = 0;
enum acl_mode mode = SMB_ACL_SET;
static char *the_acl = NULL;
fstring sharename;
bool force_acl = False;
int snum;
poptContext pc;
bool initialize_sid = False;
struct poptOption long_options[] = {
POPT_AUTOHELP
{ "remove", 'r', POPT_ARG_STRING, &the_acl, 'r', "Remove ACEs", "ACL" },
{ "modify", 'm', POPT_ARG_STRING, &the_acl, 'm', "Modify existing ACEs", "ACL" },
{ "add", 'a', POPT_ARG_STRING, &the_acl, 'a', "Add ACEs", "ACL" },
{ "replace", 'R', POPT_ARG_STRING, &the_acl, 'R', "Overwrite share permission ACL", "ACLS" },
{ "delete", 'D', POPT_ARG_NONE, NULL, 'D', "Delete the entire security descriptor" },
{ "view", 'v', POPT_ARG_NONE, NULL, 'v', "View current share permissions" },
{ "machine-sid", 'M', POPT_ARG_NONE, NULL, 'M', "Initialize the machine SID" },
{ "force", 'F', POPT_ARG_NONE, NULL, 'F', "Force storing the ACL", "ACLS" },
POPT_COMMON_SAMBA
{ NULL }
};
if ( !(ctx = talloc_stackframe()) ) {
fprintf( stderr, "Failed to initialize talloc context!\n");
return -1;
}
/* set default debug level to 1 regardless of what smb.conf sets */
setup_logging( "sharesec", DEBUG_STDERR);
DEBUGLEVEL_CLASS[DBGC_ALL] = 1;
pc = poptGetContext("sharesec", argc, argv, long_options, 0);
poptSetOtherOptionHelp(pc, "sharename\n");
while ((opt = poptGetNextOpt(pc)) != -1) {
switch (opt) {
case 'r':
the_acl = smb_xstrdup(poptGetOptArg(pc));
mode = SMB_ACL_DELETE;
break;
case 'm':
the_acl = smb_xstrdup(poptGetOptArg(pc));
mode = SMB_ACL_MODIFY;
break;
case 'a':
the_acl = smb_xstrdup(poptGetOptArg(pc));
mode = SMB_ACL_ADD;
break;
case 'R':
the_acl = smb_xstrdup(poptGetOptArg(pc));
mode = SMB_ACL_SET;
break;
case 'D':
mode = SMB_SD_DELETE;
break;
case 'v':
mode = SMB_ACL_VIEW;
break;
case 'F':
force_acl = True;
break;
case 'M':
initialize_sid = True;
break;
}
}
setlinebuf(stdout);
load_case_tables();
lp_load( get_dyn_CONFIGFILE(), False, False, False, True );
/* check for initializing secrets.tdb first */
if ( initialize_sid ) {
struct dom_sid *sid = get_global_sam_sid();
if ( !sid ) {
fprintf( stderr, "Failed to retrieve Machine SID!\n");
return 3;
}
printf ("%s\n", sid_string_tos( sid ) );
return 0;
}
if ( mode == SMB_ACL_VIEW && force_acl ) {
fprintf( stderr, "Invalid combination of -F and -v\n");
return -1;
}
/* get the sharename */
if(!poptPeekArg(pc)) {
poptPrintUsage(pc, stderr, 0);
return -1;
}
fstrcpy(sharename, poptGetArg(pc));
snum = lp_servicenumber( sharename );
if ( snum == -1 && !force_acl ) {
fprintf( stderr, "Invalid sharename: %s\n", sharename);
return -1;
}
retval = change_share_sec(ctx, sharename, the_acl, mode);
talloc_destroy(ctx);
return retval;
}
|