/* 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 <http://www.gnu.org/licenses/>. */ #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] == '$' ) is_machine_account = True; alpha_strcpy( smb_user_name, tmp, SAFE_NETBIOS_CHARS, sizeof(smb_user_name)-1 ); if ( is_machine_account ) { len = strlen( smb_user_name ); smb_user_name[len-1] = '$'; } } 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 %$(NAME) in p and the whole string in str expand it as an environment variable. Return a new allocated and expanded string. Based on code by Branko Cibej <branko.cibej@hermes.si> When this is called p points at the '%' character. May substitute multiple occurrencies of the same env var. ********************************************************************/ static char * realloc_expand_env_var(char *str, char *p) { char *envname; char *envval; char *q, *r; int copylen; if (p[0] != '%' || p[1] != '$' || 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 %$(NAME) string. */ r = p + 3; copylen = q - r; /* reserve space for use later add %$() 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 ); }; 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) { 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()) { 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 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, 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; 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()); 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 ); } }