From a8b8017c34fefcb763d8b06c294b58d1c480b2e4 Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Thu, 31 Mar 2011 23:16:42 +0200 Subject: [PATCH] initramfs: Use KBUILD_BUILD_TIMESTAMP for generated entries gen_init_cpio gets the current time and uses it for each symlink, special file, and directory. Grab the current time once and make it possible to override it with the KBUILD_BUILD_TIMESTAMP variable for reproducible builds. Signed-off-by: Michal Marek --- Documentation/kbuild/kbuild.txt | 3 +- scripts/gen_initramfs_list.sh | 9 +++++- usr/gen_init_cpio.c | 53 +++++++++++++++++++++++++-------- 3 files changed, 50 insertions(+), 15 deletions(-) diff --git a/Documentation/kbuild/kbuild.txt b/Documentation/kbuild/kbuild.txt index f11ebb33e4a6ee..646e2c114ffff3 100644 --- a/Documentation/kbuild/kbuild.txt +++ b/Documentation/kbuild/kbuild.txt @@ -205,7 +205,8 @@ gcc -W... options for more extensive build-time checking. KBUILD_BUILD_TIMESTAMP -------------------------------------------------- Setting this to a date string overrides the timestamp used in the -UTS_VERSION definition (uname -v in the running kernel). The default value +UTS_VERSION definition (uname -v in the running kernel). The value has to +be a string that can be passed to date -d. The default value is the output of the date command at one point during build. KBUILD_BUILD_USER, KBUILD_BUILD_HOST diff --git a/scripts/gen_initramfs_list.sh b/scripts/gen_initramfs_list.sh index 4a43fe12d1792c..d44cf675bc22a6 100644 --- a/scripts/gen_initramfs_list.sh +++ b/scripts/gen_initramfs_list.sh @@ -287,8 +287,15 @@ done # we are carefull to delete tmp files if [ ! -z ${output_file} ]; then if [ -z ${cpio_file} ]; then + timestamp= + if test -n "$KBUILD_BUILD_TIMESTAMP"; then + timestamp="$(date -d"$KBUILD_BUILD_TIMESTAMP" +%s || :)" + if test -n "$timestamp"; then + timestamp="-t $timestamp" + fi + fi cpio_tfile="$(mktemp ${TMPDIR:-/tmp}/cpiofile.XXXXXX)" - usr/gen_init_cpio ${cpio_list} > ${cpio_tfile} + usr/gen_init_cpio $timestamp ${cpio_list} > ${cpio_tfile} else cpio_tfile=${cpio_file} fi diff --git a/usr/gen_init_cpio.c b/usr/gen_init_cpio.c index 7f06884ecd41b5..af0f22fb1ef71e 100644 --- a/usr/gen_init_cpio.c +++ b/usr/gen_init_cpio.c @@ -22,6 +22,7 @@ static unsigned int offset; static unsigned int ino = 721; +static time_t default_mtime; struct file_handler { const char *type; @@ -102,7 +103,6 @@ static int cpio_mkslink(const char *name, const char *target, unsigned int mode, uid_t uid, gid_t gid) { char s[256]; - time_t mtime = time(NULL); if (name[0] == '/') name++; @@ -114,7 +114,7 @@ static int cpio_mkslink(const char *name, const char *target, (long) uid, /* uid */ (long) gid, /* gid */ 1, /* nlink */ - (long) mtime, /* mtime */ + (long) default_mtime, /* mtime */ (unsigned)strlen(target)+1, /* filesize */ 3, /* major */ 1, /* minor */ @@ -152,7 +152,6 @@ static int cpio_mkgeneric(const char *name, unsigned int mode, uid_t uid, gid_t gid) { char s[256]; - time_t mtime = time(NULL); if (name[0] == '/') name++; @@ -164,7 +163,7 @@ static int cpio_mkgeneric(const char *name, unsigned int mode, (long) uid, /* uid */ (long) gid, /* gid */ 2, /* nlink */ - (long) mtime, /* mtime */ + (long) default_mtime, /* mtime */ 0, /* filesize */ 3, /* major */ 1, /* minor */ @@ -242,7 +241,6 @@ static int cpio_mknod(const char *name, unsigned int mode, unsigned int maj, unsigned int min) { char s[256]; - time_t mtime = time(NULL); if (dev_type == 'b') mode |= S_IFBLK; @@ -259,7 +257,7 @@ static int cpio_mknod(const char *name, unsigned int mode, (long) uid, /* uid */ (long) gid, /* gid */ 1, /* nlink */ - (long) mtime, /* mtime */ + (long) default_mtime, /* mtime */ 0, /* filesize */ 3, /* major */ 1, /* minor */ @@ -460,7 +458,7 @@ static int cpio_mkfile_line(const char *line) static void usage(const char *prog) { fprintf(stderr, "Usage:\n" - "\t%s \n" + "\t%s [-t ] \n" "\n" " is a file containing newline separated entries that\n" "describe the files to be included in the initramfs archive:\n" @@ -491,7 +489,11 @@ static void usage(const char *prog) "nod /dev/console 0600 0 0 c 5 1\n" "dir /root 0700 0 0\n" "dir /sbin 0755 0 0\n" - "file /sbin/kinit /usr/src/klibc/kinit/kinit 0755 0 0\n", + "file /sbin/kinit /usr/src/klibc/kinit/kinit 0755 0 0\n" + "\n" + " is time in seconds since Epoch that will be used\n" + "as mtime for symlinks, special files and directories. The default\n" + "is to use the current time for these entries.\n", prog); } @@ -529,17 +531,42 @@ int main (int argc, char *argv[]) char *args, *type; int ec = 0; int line_nr = 0; + const char *filename; + + default_mtime = time(NULL); + while (1) { + int opt = getopt(argc, argv, "t:h"); + char *invalid; - if (2 != argc) { + if (opt == -1) + break; + switch (opt) { + case 't': + default_mtime = strtol(optarg, &invalid, 10); + if (!*optarg || *invalid) { + fprintf(stderr, "Invalid timestamp: %s\n", + optarg); + usage(argv[0]); + exit(1); + } + break; + case 'h': + case '?': + usage(argv[0]); + exit(opt == 'h' ? 0 : 1); + } + } + + if (argc - optind != 1) { usage(argv[0]); exit(1); } - - if (!strcmp(argv[1], "-")) + filename = argv[optind]; + if (!strcmp(filename, "-")) cpio_list = stdin; - else if (! (cpio_list = fopen(argv[1], "r"))) { + else if (!(cpio_list = fopen(filename, "r"))) { fprintf(stderr, "ERROR: unable to open '%s': %s\n\n", - argv[1], strerror(errno)); + filename, strerror(errno)); usage(argv[0]); exit(1); }