From ad4cff2625651bda9de25de9aba96bdf213d0a0a Mon Sep 17 00:00:00 2001 From: Richard Jones Date: Wed, 28 Jul 2010 15:38:57 +0100 Subject: [PATCH] New API: file-architecture This change simply converts the existing Perl-only function file_architecture into a core API call. The core API call is written in C and available in all languages and from guestfish. --- README | 4 + configure.ac | 19 +++ perl/lib/Sys/Guestfs/Lib.pm | 147 +---------------------- perl/t/510-lib-file-arch.t | 70 ----------- po/POTFILES.in | 1 + src/Makefile.am | 3 +- src/generator.ml | 128 ++++++++++++++++++++ src/inspect.c | 280 ++++++++++++++++++++++++++++++++++++++++++++ 8 files changed, 437 insertions(+), 215 deletions(-) delete mode 100644 perl/t/510-lib-file-arch.t create mode 100644 src/inspect.c diff --git a/README b/README index ea1da1f..867bc56 100644 --- a/README +++ b/README @@ -48,6 +48,10 @@ Requirements - XDR, rpcgen (on Linux these are provided by glibc) +- pcre (Perl Compatible Regular Expressions C library) + +- libmagic (the library that corresponds to the 'file' command) + - squashfs-tools (mksquashfs only) - genisoimage / mkisofs diff --git a/configure.ac b/configure.ac index 1922773..e04357d 100644 --- a/configure.ac +++ b/configure.ac @@ -185,6 +185,15 @@ AC_ARG_ENABLE([appliance], AM_CONDITIONAL([ENABLE_APPLIANCE],[test "x$enable_appliance" = "xyes"]) AC_MSG_RESULT([$enable_appliance]) +dnl Check for PCRE. +AC_CHECK_LIB([pcre],[pcre_compile], + [AC_SUBST([LIBPCRE], ["-lpcre"])], + [AC_MSG_FAILURE( + [Perl Compatible Regular Expressions library (PCRE) is required])]) +AC_CHECK_HEADER([pcre.h],[], + [AC_MSG_FAILURE( + [Perl Compatible Regular Expressions library (PCRE) header file pcre.h is required])]) + dnl Check for rpcgen and XDR library. rpcgen is optional. AC_CHECK_PROG([RPCGEN],[rpcgen],[rpcgen],[no]) AM_CONDITIONAL([HAVE_RPCGEN],[test "x$RPCGEN" != "xno"]) @@ -449,6 +458,16 @@ dnl For i18n. AM_GNU_GETTEXT([external]) AM_GNU_GETTEXT_VERSION([0.17]) +dnl libmagic (required) +AC_CHECK_LIB([magic],[magic_file],[ + AC_SUBST([LIBMAGIC], ["-lmagic"]) + ],[ + AC_MSG_FAILURE([libmagic is required]) + ]) +AC_CHECK_HEADER([magic.h],[],[ + AC_MSG_FAILURE([magic.h header file is required]) + ]) + dnl hivex library (highly recommended). dnl This used to be a part of libguestfs, but was spun off into its dnl own separate upstream project in libguestfs 1.0.85. diff --git a/perl/lib/Sys/Guestfs/Lib.pm b/perl/lib/Sys/Guestfs/Lib.pm index bdc788e..bb97506 100644 --- a/perl/lib/Sys/Guestfs/Lib.pm +++ b/perl/lib/Sys/Guestfs/Lib.pm @@ -347,159 +347,18 @@ sub resolve_windows_path =head2 file_architecture - $arch = file_architecture ($g, $path) +Deprecated function. Replace any calls to this function with: -The C function lets you get the architecture for a -particular binary or library in the guest. By "architecture" we mean -what processor it is compiled for (eg. C or C). - -The function works on at least the following types of files: - -=over 4 - -=item * - -many types of Un*x binary - -=item * - -many types of Un*x shared library - -=item * - -Windows Win32 and Win64 binaries - -=item * - -Windows Win32 and Win64 DLLs - -Win32 binaries and DLLs return C. - -Win64 binaries and DLLs return C. - -=item * - -Linux kernel modules - -=item * - -Linux new-style initrd images - -=item * - -some non-x86 Linux vmlinuz kernels - -=back - -What it can't do currently: - -=over 4 - -=item * - -static libraries (libfoo.a) - -=item * - -Linux old-style initrd as compressed ext2 filesystem (RHEL 3) - -=item * - -x86 Linux vmlinuz kernels - -x86 vmlinuz images (bzImage format) consist of a mix of 16-, 32- and -compressed code, and are horribly hard to unpack. If you want to find -the architecture of a kernel, use the architecture of the associated -initrd or kernel module(s) instead. - -=back + $g->file_architecture ($path); =cut -sub _elf_arch_to_canonical -{ - local $_ = shift; - - if ($_ eq "Intel 80386") { - return "i386"; - } elsif ($_ eq "Intel 80486") { - return "i486"; # probably not in the wild - } elsif ($_ eq "x86-64") { - return "x86_64"; - } elsif ($_ eq "AMD x86-64") { - return "x86_64"; - } elsif (/SPARC32/) { - return "sparc"; - } elsif (/SPARC V9/) { - return "sparc64"; - } elsif ($_ eq "IA-64") { - return "ia64"; - } elsif (/64.*PowerPC/) { - return "ppc64"; - } elsif (/PowerPC/) { - return "ppc"; - } else { - warn __x("returning non-canonical architecture type '{arch}'", - arch => $_); - return $_; - } -} - -my @_initrd_binaries = ("nash", "modprobe", "sh", "bash"); - sub file_architecture { - local $_; my $g = shift; my $path = shift; - # Our basic tool is 'file' ... - my $file = $g->file ($path); - - if ($file =~ /ELF.*(?:executable|shared object|relocatable), (.+?),/) { - # ELF executable or shared object. We need to convert - # what file(1) prints into the canonical form. - return _elf_arch_to_canonical ($1); - } elsif ($file =~ /PE32 executable/) { - return "i386"; # Win32 executable or DLL - } elsif ($file =~ /PE32\+ executable/) { - return "x86_64"; # Win64 executable or DLL - } - - elsif ($file =~ /cpio archive/) { - # Probably an initrd. - my $zcat = "cat"; - if ($file =~ /gzip/) { - $zcat = "zcat"; - } elsif ($file =~ /bzip2/) { - $zcat = "bzcat"; - } - - # Download and unpack it to find a binary file. - my $dir = tempdir (CLEANUP => 1); - $g->download ($path, "$dir/initrd"); - - my $bins = join " ", map { "bin/$_" } @_initrd_binaries; - my $cmd = "cd $dir && $zcat initrd | cpio --quiet -id $bins"; - my $r = system ($cmd); - die __x("cpio command failed: {error}", error => $?) - unless $r == 0; - - foreach my $bin (@_initrd_binaries) { - if (-f "$dir/bin/$bin") { - $_ = `file $dir/bin/$bin`; - if (/ELF.*executable, (.+?),/) { - return _elf_arch_to_canonical ($1); - } - } - } - - die __x("file_architecture: no known binaries found in initrd image: {path}", - path => $path); - } - - die __x("file_architecture: unknown architecture: {path}", - path => $path); + return $g->file_architecture ($path); } =head1 OPERATING SYSTEM INSPECTION FUNCTIONS diff --git a/perl/t/510-lib-file-arch.t b/perl/t/510-lib-file-arch.t deleted file mode 100644 index dfe32bc..0000000 --- a/perl/t/510-lib-file-arch.t +++ /dev/null @@ -1,70 +0,0 @@ -# libguestfs Perl bindings -*- perl -*- -# Copyright (C) 2009 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., 675 Mass Ave, Cambridge, MA 02139, USA. - -use strict; -use warnings; - -BEGIN { - use Test::More; - eval "use Locale::TextDomain";; - if (exists $INC{"Locale/TextDomain.pm"}) { - plan tests => 16; - } else { - plan skip_all => "no perl-libintl module"; - exit 0; - } -} - -use Sys::Guestfs; -use Sys::Guestfs::Lib; - -my $h = Sys::Guestfs->new (); -ok ($h); - -$h->add_drive_ro ("../images/test.iso"); -ok (1); - -$h->launch (); -ok (1); - -$h->mount_ro ("/dev/sda", "/"); -ok (1); - -is (Sys::Guestfs::Lib::file_architecture ($h, "/bin-i586-dynamic"), - "i386"); -is (Sys::Guestfs::Lib::file_architecture ($h, "/bin-sparc-dynamic"), - "sparc"); -is (Sys::Guestfs::Lib::file_architecture ($h, "/bin-win32.exe"), - "i386"); -is (Sys::Guestfs::Lib::file_architecture ($h, "/bin-win64.exe"), - "x86_64"); -is (Sys::Guestfs::Lib::file_architecture ($h, "/bin-x86_64-dynamic"), - "x86_64"); -is (Sys::Guestfs::Lib::file_architecture ($h, "/lib-i586.so"), - "i386"); -is (Sys::Guestfs::Lib::file_architecture ($h, "/lib-sparc.so"), - "sparc"); -is (Sys::Guestfs::Lib::file_architecture ($h, "/lib-win32.dll"), - "i386"); -is (Sys::Guestfs::Lib::file_architecture ($h, "/lib-win64.dll"), - "x86_64"); -is (Sys::Guestfs::Lib::file_architecture ($h, "/lib-x86_64.so"), - "x86_64"); -is (Sys::Guestfs::Lib::file_architecture ($h, "/initrd-x86_64.img"), - "x86_64"); -is (Sys::Guestfs::Lib::file_architecture ($h, "/initrd-x86_64.img.gz"), - "x86_64"); diff --git a/po/POTFILES.in b/po/POTFILES.in index fdc2b70..bf066ea 100644 --- a/po/POTFILES.in +++ b/po/POTFILES.in @@ -102,6 +102,7 @@ ruby/ext/guestfs/_guestfs.c src/actions.c src/bindtests.c src/guestfs.c +src/inspect.c src/launch.c src/proto.c test-tool/helper.c diff --git a/src/Makefile.am b/src/Makefile.am index 4135c8c..61cec04 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -126,11 +126,12 @@ libguestfs_la_SOURCES = \ gettext.h \ actions.c \ bindtests.c \ + inspect.c \ launch.c \ proto.c \ libguestfs.syms -libguestfs_la_LIBADD = $(LTLIBTHREAD) ../gnulib/lib/libgnu.la +libguestfs_la_LIBADD = $(LIBPCRE) $(LIBMAGIC) $(LTLIBTHREAD) ../gnulib/lib/libgnu.la # Make libguestfs include the convenience library. noinst_LTLIBRARIES = libprotocol.la diff --git a/src/generator.ml b/src/generator.ml index 6791a6a..77c7642 100755 --- a/src/generator.ml +++ b/src/generator.ml @@ -940,6 +940,134 @@ to specify the QEMU interface emulation to use at run time."); This is the same as C but it allows you to specify the QEMU interface emulation to use at run time."); + ("file_architecture", (RString "arch", [Pathname "filename"]), -1, [], + [InitISOFS, Always, TestOutput ( + [["file_architecture"; "/bin-i586-dynamic"]], "i386"); + InitISOFS, Always, TestOutput ( + [["file_architecture"; "/bin-sparc-dynamic"]], "sparc"); + InitISOFS, Always, TestOutput ( + [["file_architecture"; "/bin-win32.exe"]], "i386"); + InitISOFS, Always, TestOutput ( + [["file_architecture"; "/bin-win64.exe"]], "x86_64"); + InitISOFS, Always, TestOutput ( + [["file_architecture"; "/bin-x86_64-dynamic"]], "x86_64"); + InitISOFS, Always, TestOutput ( + [["file_architecture"; "/lib-i586.so"]], "i386"); + InitISOFS, Always, TestOutput ( + [["file_architecture"; "/lib-sparc.so"]], "sparc"); + InitISOFS, Always, TestOutput ( + [["file_architecture"; "/lib-win32.dll"]], "i386"); + InitISOFS, Always, TestOutput ( + [["file_architecture"; "/lib-win64.dll"]], "x86_64"); + InitISOFS, Always, TestOutput ( + [["file_architecture"; "/lib-x86_64.so"]], "x86_64"); + InitISOFS, Always, TestOutput ( + [["file_architecture"; "/initrd-x86_64.img"]], "x86_64"); + InitISOFS, Always, TestOutput ( + [["file_architecture"; "/initrd-x86_64.img.gz"]], "x86_64");], + "detect the architecture of a binary file", + "\ +This detects the architecture of the binary C, +and returns it if known. + +Currently defined architectures are: + +=over 4 + +=item \"i386\" + +This string is returned for all 32 bit i386, i486, i586, i686 binaries +irrespective of the precise processor requirements of the binary. + +=item \"x86_64\" + +64 bit x86-64. + +=item \"sparc\" + +32 bit SPARC. + +=item \"sparc64\" + +64 bit SPARC V9 and above. + +=item \"ia64\" + +Intel Itanium. + +=item \"ppc\" + +32 bit Power PC. + +=item \"ppc64\" + +64 bit Power PC. + +=back + +Libguestfs may return other architecture strings in future. + +The function works on at least the following types of files: + +=over 4 + +=item * + +many types of Un*x and Linux binary + +=item * + +many types of Un*x and Linux shared library + +=item * + +Windows Win32 and Win64 binaries + +=item * + +Windows Win32 and Win64 DLLs + +Win32 binaries and DLLs return C. + +Win64 binaries and DLLs return C. + +=item * + +Linux kernel modules + +=item * + +Linux new-style initrd images + +=item * + +some non-x86 Linux vmlinuz kernels + +=back + +What it can't do currently: + +=over 4 + +=item * + +static libraries (libfoo.a) + +=item * + +Linux old-style initrd as compressed ext2 filesystem (RHEL 3) + +=item * + +x86 Linux vmlinuz kernels + +x86 vmlinuz images (bzImage format) consist of a mix of 16-, 32- and +compressed code, and are horribly hard to unpack. If you want to find +the architecture of a kernel, use the architecture of the associated +initrd or kernel module(s) instead. + +=back"); + ] (* daemon_functions are any functions which cause some action diff --git a/src/inspect.c b/src/inspect.c new file mode 100644 index 0000000..d19e23b --- /dev/null +++ b/src/inspect.c @@ -0,0 +1,280 @@ +/* libguestfs + * Copyright (C) 2010 Red Hat Inc. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include + +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#include "ignore-value.h" + +#include "guestfs.h" +#include "guestfs-internal.h" +#include "guestfs-internal-actions.h" +#include "guestfs_protocol.h" + +/* Compile all the regular expressions once when the shared library is + * loaded. PCRE is thread safe so we're supposedly OK here if + * multiple threads call into the libguestfs API functions below + * simultaneously. + */ +static pcre *re_file_elf; +static pcre *re_file_win64; +static pcre *re_elf_ppc64; + +static void compile_regexps (void) __attribute__((constructor)); +static void +compile_regexps (void) +{ + const char *err; + int offset; + +#define COMPILE(re,pattern,options) \ + do { \ + re = pcre_compile ((pattern), (options), &err, &offset, NULL); \ + if (re == NULL) { \ + ignore_value (write (2, err, strlen (err))); \ + abort (); \ + } \ + } while (0) + + COMPILE (re_file_elf, + "ELF.*(?:executable|shared object|relocatable), (.+?),", 0); + COMPILE (re_elf_ppc64, "64.*PowerPC", 0); +} + +/* Match a regular expression which contains no captures. Returns + * true if it matches or false if it doesn't. + */ +static int +match (guestfs_h *g, const char *str, const pcre *re) +{ + size_t len = strlen (str); + int vec[30], r; + + r = pcre_exec (re, NULL, str, len, 0, 0, vec, sizeof vec / sizeof vec[0]); + if (r == PCRE_ERROR_NOMATCH) + return 0; + if (r != 1) { + /* Internal error -- should not happen. */ + fprintf (stderr, "libguestfs: %s: %s: internal error: pcre_exec returned unexpected error code %d when matching against the string \"%s\"\n", + __FILE__, __func__, r, str); + return 0; + } + + return 1; +} + +/* Match a regular expression which contains exactly one capture. If + * the string matches, return the capture, otherwise return NULL. The + * caller must free the result. + */ +static char * +match1 (guestfs_h *g, const char *str, const pcre *re) +{ + size_t len = strlen (str); + int vec[30], r; + + r = pcre_exec (re, NULL, str, len, 0, 0, vec, sizeof vec / sizeof vec[0]); + if (r == PCRE_ERROR_NOMATCH) + return NULL; + if (r != 2) { + /* Internal error -- should not happen. */ + fprintf (stderr, "libguestfs: %s: %s: internal error: pcre_exec returned unexpected error code %d when matching against the string \"%s\"\n", + __FILE__, __func__, r, str); + return NULL; + } + + return safe_strndup (g, &str[vec[2]], vec[3]-vec[2]); +} + +/* Convert output from 'file' command on ELF files to the canonical + * architecture string. Caller must free the result. + */ +static char * +canonical_elf_arch (guestfs_h *g, const char *elf_arch) +{ + const char *r; + + if (strstr (elf_arch, "Intel 80386")) + r = "i386"; + else if (strstr (elf_arch, "Intel 80486")) + r = "i486"; + else if (strstr (elf_arch, "x86-64")) + r = "x86_64"; + else if (strstr (elf_arch, "AMD x86-64")) + r = "x86_64"; + else if (strstr (elf_arch, "SPARC32")) + r = "sparc"; + else if (strstr (elf_arch, "SPARC V9")) + r = "sparc64"; + else if (strstr (elf_arch, "IA-64")) + r = "ia64"; + else if (match (g, elf_arch, re_elf_ppc64)) + r = "ppc64"; + else if (strstr (elf_arch, "PowerPC")) + r = "ppc"; + else + r = elf_arch; + + char *ret = safe_strdup (g, r); + return ret; +} + +static int +is_regular_file (const char *filename) +{ + struct stat statbuf; + + return lstat (filename, &statbuf) == 0 && S_ISREG (statbuf.st_mode); +} + +/* Download and uncompress the cpio file to find binaries within. + * Notes: + * (1) Two lists must be identical. + * (2) Implicit limit of 31 bytes for length of each element (see code + * below). + */ +#define INITRD_BINARIES1 "bin/ls bin/rm bin/modprobe sbin/modprobe bin/sh bin/bash bin/dash bin/nash" +#define INITRD_BINARIES2 {"bin/ls", "bin/rm", "bin/modprobe", "sbin/modprobe", "bin/sh", "bin/bash", "bin/dash", "bin/nash"} + +static char * +cpio_arch (guestfs_h *g, const char *file, const char *path) +{ + char *ret = NULL; + + const char *method; + if (strstr (file, "gzip")) + method = "zcat"; + else if (strstr (file, "bzip2")) + method = "bzcat"; + else + method = "cat"; + + char dir[] = "/tmp/initrd.XXXXXX"; +#define dir_len (sizeof dir) + if (mkdtemp (dir) == NULL) { + perrorf (g, "mkdtemp"); + goto out; + } + + char dir_initrd[dir_len + 16]; + snprintf (dir_initrd, dir_len + 16, "%s/initrd", dir); + if (guestfs_download (g, path, dir_initrd) == -1) + goto out; + + char cmd[dir_len + 256]; + snprintf (cmd, dir_len + 256, + "cd %s && %s initrd | cpio --quiet -id " INITRD_BINARIES1, + dir, method); + int r = system (cmd); + if (r == -1 || WEXITSTATUS (r) != 0) { + perrorf (g, "cpio command failed"); + goto out; + } + + char bin[dir_len + 32]; + const char *bins[] = INITRD_BINARIES2; + size_t i; + for (i = 0; i < sizeof bins / sizeof bins[0]; ++i) { + snprintf (bin, dir_len + 32, "%s/%s", dir, bins[i]); + + if (is_regular_file (bin)) { + int flags = g->verbose ? MAGIC_DEBUG : 0; + flags |= MAGIC_ERROR | MAGIC_RAW; + + magic_t m = magic_open (flags); + if (m == NULL) { + perrorf (g, "magic_open"); + goto out; + } + + if (magic_load (m, NULL) == -1) { + perrorf (g, "magic_load: default magic database file"); + magic_close (m); + goto out; + } + + const char *line = magic_file (m, bin); + if (line == NULL) { + perrorf (g, "magic_file: %s", bin); + magic_close (m); + goto out; + } + + char *elf_arch; + if ((elf_arch = match1 (g, line, re_file_elf)) != NULL) { + ret = canonical_elf_arch (g, elf_arch); + free (elf_arch); + magic_close (m); + goto out; + } + magic_close (m); + } + } + error (g, "file_architecture: could not determine architecture of cpio archive"); + + out: + /* Free up the temporary directory. Note the directory name cannot + * contain shell meta-characters because of the way it was + * constructed above. + */ + snprintf (cmd, dir_len + 256, "rm -rf %s", dir); + ignore_value (system (cmd)); + + return ret; +#undef dir_len +} + +char * +guestfs__file_architecture (guestfs_h *g, const char *path) +{ + char *file = NULL; + char *elf_arch = NULL; + char *ret = NULL; + + /* Get the output of the "file" command. Note that because this + * runs in the daemon, LANG=C so it's in English. + */ + file = guestfs_file (g, path); + if (file == NULL) + return NULL; + + if ((elf_arch = match1 (g, file, re_file_elf)) != NULL) + ret = canonical_elf_arch (g, elf_arch); + else if (strstr (file, "PE32 executable")) + ret = safe_strdup (g, "i386"); + else if (strstr (file, "PE32+ executable")) + ret = safe_strdup (g, "x86_64"); + else if (strstr (file, "cpio archive")) + ret = cpio_arch (g, file, path); + else + error (g, "file_architecture: unknown architecture: %s", path); + + free (file); + free (elf_arch); + return ret; /* caller frees */ +} -- 1.8.3.1