From 8daa83a594a2e98f39d764422bfbdbc62c9efd44 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Fri, 19 Apr 2024 19:20:00 +0200 Subject: Adding upstream version 2:4.20.0+dfsg. Signed-off-by: Daniel Baumann --- source3/modules/vfs_expand_msdfs.c | 270 +++++++++++++++++++++++++++++++++++++ 1 file changed, 270 insertions(+) create mode 100644 source3/modules/vfs_expand_msdfs.c (limited to 'source3/modules/vfs_expand_msdfs.c') diff --git a/source3/modules/vfs_expand_msdfs.c b/source3/modules/vfs_expand_msdfs.c new file mode 100644 index 0000000..503ee84 --- /dev/null +++ b/source3/modules/vfs_expand_msdfs.c @@ -0,0 +1,270 @@ +/* + * Expand msdfs targets based on client IP + * + * Copyright (C) Volker Lendecke, 2004 + * + * 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" +#include "system/filesys.h" +#include "smbd/smbd.h" +#include "../librpc/gen_ndr/ndr_netlogon.h" +#include "smbd/globals.h" +#include "auth.h" +#include "../lib/tsocket/tsocket.h" +#include "msdfs.h" +#include "source3/lib/substitute.h" + +#undef DBGC_CLASS +#define DBGC_CLASS DBGC_VFS + +/********************************************************** + Under mapfile we expect a table of the following format: + + IP-Prefix whitespace expansion + + For example: + 192.168.234 local.samba.org + 192.168 remote.samba.org + default.samba.org + + This is to redirect a DFS client to a host close to it. +***********************************************************/ + +static char *read_target_host(TALLOC_CTX *ctx, const char *mapfile, + const char *clientaddr) +{ + FILE *f; + char buf[1024]; + char *space = buf; + bool found = false; + + f = fopen(mapfile, "r"); + + if (f == NULL) { + DEBUG(0,("can't open IP map %s. Error %s\n", + mapfile, strerror(errno) )); + return NULL; + } + + DEBUG(10, ("Scanning mapfile [%s]\n", mapfile)); + + while (fgets(buf, sizeof(buf), f) != NULL) { + + if ((strlen(buf) > 0) && (buf[strlen(buf)-1] == '\n')) + buf[strlen(buf)-1] = '\0'; + + DEBUG(10, ("Scanning line [%s]\n", buf)); + + space = strchr_m(buf, ' '); + + if (space == NULL) { + DEBUG(0, ("Ignoring invalid line %s\n", buf)); + continue; + } + + *space = '\0'; + + if (strncmp(clientaddr, buf, strlen(buf)) == 0) { + found = true; + break; + } + } + + fclose(f); + + if (!found) { + return NULL; + } + + space += 1; + + while (isspace(*space)) + space += 1; + + return talloc_strdup(ctx, space); +} + +/********************************************************** + + Expand the msdfs target host using read_target_host + explained above. The syntax used in the msdfs link is + + msdfs:@table-filename@/share + + Everything between and including the two @-signs is + replaced by the substitution string found in the table + described above. + +***********************************************************/ + +static char *expand_msdfs_target(TALLOC_CTX *ctx, + connection_struct *conn, + char *target) +{ + const struct loadparm_substitution *lp_sub = + loadparm_s3_global_substitution(); + char *mapfilename = NULL; + char *filename_start = strchr_m(target, '@'); + char *filename_end = NULL; + int filename_len = 0; + char *targethost = NULL; + char *new_target = NULL; + char *raddr; + + if (filename_start == NULL) { + DEBUG(10, ("No filename start in %s\n", target)); + return NULL; + } + + filename_end = strchr_m(filename_start+1, '@'); + + if (filename_end == NULL) { + DEBUG(10, ("No filename end in %s\n", target)); + return NULL; + } + + filename_len = PTR_DIFF(filename_end, filename_start+1); + mapfilename = talloc_strdup(ctx, filename_start+1); + if (!mapfilename) { + return NULL; + } + mapfilename[filename_len] = '\0'; + + /* + * dfs links returned have had '/' characters replaced with '\'. + * Return them to '/' so we can have absolute path mapfilenames. + */ + string_replace(mapfilename, '\\', '/'); + + DEBUG(10, ("Expanding from table [%s]\n", mapfilename)); + + raddr = tsocket_address_inet_addr_string(conn->sconn->remote_address, + ctx); + if (raddr == NULL) { + return NULL; + } + + targethost = read_target_host(ctx, mapfilename, raddr); + if (targethost == NULL) { + DEBUG(1, ("Could not expand target host from file %s\n", + mapfilename)); + return NULL; + } + + targethost = talloc_sub_full(ctx, + lp_servicename(talloc_tos(), lp_sub, SNUM(conn)), + conn->session_info->unix_info->unix_name, + conn->connectpath, + conn->session_info->unix_token->gid, + conn->session_info->unix_info->sanitized_username, + conn->session_info->info->domain_name, + targethost); + + DEBUG(10, ("Expanded targethost to %s\n", targethost)); + + /* Replace the part between '@...@' */ + *filename_start = '\0'; + new_target = talloc_asprintf(ctx, + "%s%s%s", + target, + targethost, + filename_end+1); + if (!new_target) { + return NULL; + } + + DEBUG(10, ("New DFS target: %s\n", new_target)); + return new_target; +} + +static NTSTATUS expand_read_dfs_pathat(struct vfs_handle_struct *handle, + TALLOC_CTX *mem_ctx, + struct files_struct *dirfsp, + struct smb_filename *smb_fname, + struct referral **ppreflist, + size_t *preferral_count) +{ + NTSTATUS status; + size_t i; + struct referral *reflist = NULL; + size_t count = 0; + TALLOC_CTX *frame = talloc_stackframe(); + + /* + * Always call the NEXT function first, then + * modify the return if needed. + */ + status = SMB_VFS_NEXT_READ_DFS_PATHAT(handle, + mem_ctx, + dirfsp, + smb_fname, + ppreflist, + preferral_count); + + if (!NT_STATUS_IS_OK(status)) { + TALLOC_FREE(frame); + return status; + } + + /* + * This function can be called to check if a pathname + * is an MSDFS link, but not return the values of it. + * In this case ppreflist and preferral_count are NULL, + * so don't bother trying to look at any returns. + */ + if (ppreflist == NULL || preferral_count == NULL) { + TALLOC_FREE(frame); + return status; + } + + /* + * We are always returning the values returned + * returned by the NEXT call, but we might mess + * with the reflist[i].alternate_path values, + * so use local pointers to minimise indirections. + */ + count = *preferral_count; + reflist = *ppreflist; + + for (i = 0; i < count; i++) { + if (strchr_m(reflist[i].alternate_path, '@') != NULL) { + char *new_altpath = expand_msdfs_target(frame, + handle->conn, + reflist[i].alternate_path); + if (new_altpath == NULL) { + TALLOC_FREE(*ppreflist); + *preferral_count = 0; + TALLOC_FREE(frame); + return NT_STATUS_NO_MEMORY; + } + reflist[i].alternate_path = talloc_move(reflist, + &new_altpath); + } + } + TALLOC_FREE(frame); + return status; +} + +static struct vfs_fn_pointers vfs_expand_msdfs_fns = { + .read_dfs_pathat_fn = expand_read_dfs_pathat, +}; + +static_decl_vfs; +NTSTATUS vfs_expand_msdfs_init(TALLOC_CTX *ctx) +{ + return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "expand_msdfs", + &vfs_expand_msdfs_fns); +} -- cgit v1.2.3