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Diffstat (limited to 'src/febootstrap.ml')
| -rw-r--r-- | src/febootstrap.ml | 422 |
1 files changed, 422 insertions, 0 deletions
diff --git a/src/febootstrap.ml b/src/febootstrap.ml new file mode 100644 index 0000000..7e48206 --- /dev/null +++ b/src/febootstrap.ml @@ -0,0 +1,422 @@ +(* febootstrap 3 + * Copyright (C) 2009-2010 Red Hat Inc. + * + * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + *) + +open Unix +open Printf + +open Febootstrap_package_handlers +open Febootstrap_utils +open Febootstrap_cmdline + +(* Create a temporary directory for use by all the functions in this file. *) +let tmpdir = tmpdir () + +let () = + debug "%s %s" Config.package_name Config.package_version; + + (* Instead of printing out warnings as we go along, accumulate them + * in lists and print them all out at the end. + *) + let warn_unreadable = ref [] in + + (* Determine which package manager this system uses. *) + check_system (); + let ph = get_package_handler () in + + debug "selected package handler: %s" (get_package_handler_name ()); + + (* Not --names: check files exist. *) + if not names_mode then ( + List.iter ( + fun pkg -> + if not (file_exists pkg) then ( + eprintf "febootstrap: %s: no such file (did you miss out the --names option?)\n" pkg; + exit 1 + ) + ) packages + ); + + (* --names: resolve the package list to a full list of package names + * (including dependencies). + *) + let packages = + if names_mode then ( + let packages = ph.ph_resolve_dependencies_and_download packages in + debug "resolved packages: %s" (String.concat " " packages); + packages + ) + else packages in + + (* Get the list of files. *) + let files = + List.flatten ( + List.map ( + fun pkg -> + let files = ph.ph_list_files pkg in + List.map (fun (filename, ft) -> filename, ft, pkg) files + ) packages + ) in + + (* Canonicalize the name of directories, so that /a and /a/ are the same. *) + let files = + List.map ( + fun (filename, ft, pkg) -> + let len = String.length filename in + let filename = + if len > 1 (* don't rewrite "/" *) && ft.ft_dir + && filename.[len-1] = '/' then + String.sub filename 0 (len-1) + else + filename in + (filename, ft, pkg) + ) files in + + (* Sort and combine duplicate files. *) + let files = + let files = List.sort compare files in + + let combine (name1, ft1, pkg1) (name2, ft2, pkg2) = + (* Rules for combining files. *) + if ft1.ft_config || ft2.ft_config then ( + (* It's a fairly frequent bug in Fedora for two packages to + * incorrectly list the same config file. Allow this, provided + * the size of both files is 0. + *) + if ft1.ft_size = 0 && ft2.ft_size = 0 then + (name1, ft1, pkg1) + else ( + eprintf "febootstrap: error: %s is a config file which is listed in two packages (%s, %s)\n" + name1 pkg1 pkg2; + exit 1 + ) + ) + else if (ft1.ft_dir || ft2.ft_dir) && (not (ft1.ft_dir && ft2.ft_dir)) then ( + eprintf "febootstrap: error: %s appears as both directory and ordinary file (%s, %s)\n" + name1 pkg1 pkg2; + exit 1 + ) + else if ft1.ft_ghost then + (name2, ft2, pkg2) + else + (name1, ft1, pkg1) + in + + let rec loop = function + | [] -> [] + | (name1, _, _ as f1) :: (name2, _, _ as f2) :: fs when name1 = name2 -> + let f = combine f1 f2 in loop (f :: fs) + | f :: fs -> f :: loop fs + in + loop files in + + (* Because we may have excluded some packages, and also because of + * distribution packaging errors, it's not necessarily true that a + * directory is created before each file in that directory. + * Determine those missing directories and add them now. + *) + let files = + let insert_dir, dir_seen = + let h = Hashtbl.create (List.length files) in + let insert_dir dir = Hashtbl.replace h dir true in + let dir_seen dir = Hashtbl.mem h dir in + insert_dir, dir_seen + in + let files = + List.map ( + fun (path, { ft_dir = is_dir }, _ as f) -> + if is_dir then + insert_dir path; + + let rec loop path = + let parent = Filename.dirname path in + if dir_seen parent then [] + else ( + insert_dir parent; + let newdir = (parent, { ft_dir = true; ft_config = false; + ft_ghost = false; ft_mode = 0o40755; + ft_size = 0 }, + "") in + newdir :: loop parent + ) + in + List.rev (f :: loop path) + ) files in + List.flatten files in + + (* Debugging. *) + debug "%d files and directories" (List.length files); + if false then ( + List.iter ( + fun (name, { ft_dir = dir; ft_ghost = ghost; ft_config = config; + ft_mode = mode; ft_size = size }, pkg) -> + printf "%s [%s%s%s%o %d] from %s\n" name + (if dir then "dir " else "") + (if ghost then "ghost " else "") + (if config then "config " else "") + mode size + pkg + ) files + ); + + (* Split the list of files into ones for hostfiles and ones for base image. *) + let p_hmac = Str.regexp "^\\..*\\.hmac$" in + + let hostfiles = ref [] + and baseimgfiles = ref [] in + List.iter ( + fun (path, {ft_dir = dir; ft_ghost = ghost; ft_config = config} ,_ as f) -> + let file = Filename.basename path in + + (* Ignore boot files, kernel, kernel modules. Supermin appliances + * are booted from external kernel and initrd, and + * febootstrap-supermin-helper copies the host kernel modules. + * Note we want to keep the /boot and /lib/modules directory entries. + *) + if string_prefix "/boot/" path then () + else if string_prefix "/lib/modules/" path then () + + (* Always write directory names to both output files. *) + else if dir then ( + hostfiles := f :: !hostfiles; + baseimgfiles := f :: !baseimgfiles; + ) + + (* Timezone configuration is config, but copy it from host system. *) + else if path = "/etc/localtime" then + hostfiles := f :: !hostfiles + + (* Ignore FIPS files (.*.hmac) (RHBZ#654638). *) + else if Str.string_match p_hmac file 0 then () + + (* Ghost files are created empty in the base image. *) + else if ghost then + baseimgfiles := f :: !baseimgfiles + + (* For config files we can't rely on the host-installed copy + * since the admin may have modified then. We have to get the + * original file from the package and put it in the base image. + *) + else if config then + baseimgfiles := f :: !baseimgfiles + + (* Anything else comes from the host. *) + else + hostfiles := f :: !hostfiles + ) files; + let hostfiles = List.rev !hostfiles + and baseimgfiles = List.rev !baseimgfiles in + + (* Write hostfiles. *) + + (* Regexps used below. *) + let p_ld_so = Str.regexp "^ld-[.0-9]+\\.so$" in + let p_libbfd = Str.regexp "^libbfd-.*\\.so$" in + let p_libgcc = Str.regexp "^libgcc_s-.*\\.so\\.\\([0-9]+\\)$" in + let p_libntfs3g = Str.regexp "^libntfs-3g\\.so\\..*$" in + let p_lib123so = Str.regexp "^lib\\(.*\\)-[-.0-9]+\\.so$" in + let p_lib123so123 = + Str.regexp "^lib\\(.*\\)-[-.0-9]+\\.so\\.\\([0-9]+\\)\\." in + let p_libso123 = Str.regexp "^lib\\(.*\\)\\.so\\.\\([0-9]+\\)\\." in + let ntfs3g_once = ref false in + + let chan = open_out (tmpdir // "hostfiles") in + List.iter ( + fun (path, {ft_dir = is_dir; ft_ghost = ghost; ft_config = config; + ft_mode = mode }, _) -> + let dir = Filename.dirname path in + let file = Filename.basename path in + + if is_dir then + fprintf chan "%s\n" path + + (* Warn about hostfiles which are unreadable by non-root. We + * won't be able to add those to the appliance at run time, but + * there's not much else we can do about it except get the + * distros to fix this nonsense. + *) + else if mode land 0o004 = 0 then + warn_unreadable := path :: !warn_unreadable + + (* Replace fixed numbers in some library names by wildcards. *) + else if Str.string_match p_ld_so file 0 then + fprintf chan "%s/ld-*.so\n" dir + + (* Special case for libbfd. *) + else if Str.string_match p_libbfd file 0 then + fprintf chan "%s/libbfd-*.so\n" dir + + (* Special case for libgcc_s-<gccversion>-<date>.so.N *) + else if Str.string_match p_libgcc file 0 then + fprintf chan "%s/libgcc_s-*.so.%s\n" dir (Str.matched_group 1 file) + + (* Special case for libntfs-3g.so.* *) + else if Str.string_match p_libntfs3g file 0 then ( + if not !ntfs3g_once then ( + fprintf chan "%s/libntfs-3g.so.*\n" dir; + ntfs3g_once := true + ) + ) + + (* libfoo-1.2.3.so *) + else if Str.string_match p_lib123so file 0 then + fprintf chan "%s/lib%s-*.so\n" dir (Str.matched_group 1 file) + + (* libfoo-1.2.3.so.123 (but NOT '*.so.N') *) + else if Str.string_match p_lib123so123 file 0 then + fprintf chan "%s/lib%s-*.so.%s.*\n" dir + (Str.matched_group 1 file) (Str.matched_group 2 file) + + (* libfoo.so.1.2.3 (but NOT '*.so.N') *) + else if Str.string_match p_libso123 file 0 then + fprintf chan "%s/lib%s.so.%s.*\n" dir + (Str.matched_group 1 file) (Str.matched_group 2 file) + + (* Anything else comes from the host. *) + else + fprintf chan "%s\n" path + ) hostfiles; + close_out chan; + + (* Write base.img. + * + * We have to create directories and copy files to tmpdir/root + * and then call out to cpio to construct the initrd. + *) + let rootdir = tmpdir // "root" in + mkdir rootdir 0o755; + List.iter ( + fun (path, { ft_dir = is_dir; ft_ghost = ghost; ft_config = config; + ft_mode = mode }, pkg) -> + (* Always write directory names to both output files. *) + if is_dir then ( + (* Directory permissions are fixed up below. *) + if path <> "/" then mkdir (rootdir // path) 0o755 + ) + + (* Ghost files are just touched with the correct perms. *) + else if ghost then ( + let chan = open_out (rootdir // path) in + close_out chan; + chmod (rootdir // path) (mode land 0o777 lor 0o400) + ) + + (* For config files we can't rely on the host-installed copy + * since the admin may have modified it. We have to get the + * original file from the package. + *) + else if config then ( + let outfile = ph.ph_get_file_from_package pkg path in + + (* Note that the output config file might not be a regular file. *) + let statbuf = lstat outfile in + + let destfile = rootdir // path in + + (* Depending on the file type, copy it to destination. *) + match statbuf.st_kind with + | S_REG -> + (* Unreadable files (eg. /etc/gshadow). Make readable. *) + if statbuf.st_perm = 0 then chmod outfile 0o400; + let cmd = + sprintf "cp %s %s" + (Filename.quote outfile) (Filename.quote destfile) in + run_command cmd; + chmod destfile (mode land 0o777 lor 0o400) + | S_LNK -> + let link = readlink outfile in + symlink link destfile + | S_DIR -> assert false + | S_CHR + | S_BLK + | S_FIFO + | S_SOCK -> + eprintf "febootstrap: error: %s: don't know how to handle this type of file\n" path; + exit 1 + ) + + else + assert false (* should not be reached *) + ) baseimgfiles; + + (* Fix up directory permissions, in reverse order. Since we don't + * want to have a read-only directory that we can't write into above. + *) + List.iter ( + fun (path, { ft_dir = is_dir; ft_mode = mode }, _) -> + if is_dir then chmod (rootdir // path) (mode land 0o777 lor 0o700) + ) (List.rev baseimgfiles); + + (* Construct the 'base.img' initramfs. Feed in the list of filenames + * partly because we conveniently have them, and partly because + * this results in a nice alphabetical ordering in the cpio file. + *) + (*let cmd = sprintf "ls -lR %s" rootdir in + ignore (Sys.command cmd);*) + let cmd = + sprintf "(cd %s && cpio --quiet -o -0 -H newc) > %s" + rootdir (tmpdir // "base.img") in + let chan = open_process_out cmd in + List.iter (fun (path, _, _) -> fprintf chan ".%s\000" path) baseimgfiles; + let stat = close_process_out chan in + (match stat with + | WEXITED 0 -> () + | WEXITED i -> + eprintf "febootstrap: command '%s' failed (returned %d), see earlier error messages\n" cmd i; + exit i + | WSIGNALED i -> + eprintf "febootstrap: command '%s' killed by signal %d" cmd i; + exit 1 + | WSTOPPED i -> + eprintf "febootstrap: command '%s' stopped by signal %d" cmd i; + exit 1 + ); + + (* Undo directory permissions, because rm -rf can't delete files in + * unreadable directories. + *) + List.iter ( + fun (path, { ft_dir = is_dir; ft_mode = mode }, _) -> + if is_dir then chmod (rootdir // path) 0o755 + ) (List.rev baseimgfiles); + + (* Print warnings. *) + if warnings then ( + (match !warn_unreadable with + | [] -> () + | paths -> + eprintf "febootstrap: warning: some host files are unreadable by non-root\n"; + eprintf "febootstrap: warning: get your distro to fix these files:\n"; + List.iter + (fun path -> eprintf "\t%s\n%!" path) + (List.sort compare paths) + ); + ); + + (* Near-atomically copy files to the final output directory. *) + debug "writing %s ..." (outputdir // "base.img"); + let cmd = + sprintf "mv %s %s" + (Filename.quote (tmpdir // "base.img")) + (Filename.quote (outputdir // "base.img")) in + run_command cmd; + debug "writing %s ..." (outputdir // "hostfiles"); + let cmd = + sprintf "mv %s %s" + (Filename.quote (tmpdir // "hostfiles")) + (Filename.quote (outputdir // "hostfiles")) in + run_command cmd |