83 lines
2.6 KiB
Diff
83 lines
2.6 KiB
Diff
|
From f3f431a712729a1af94d01bd1bfde17a252ff02c Mon Sep 17 00:00:00 2001
|
||
|
|
From: Paul Kocialkowski <contact@paulk.fr>
|
||
|
|
Date: Sun, 26 Jul 2015 18:48:15 +0200
|
||
|
|
Subject: [PATCH] Reproducible U-Boot build support, using SOURCE_DATE_EPOCH
|
||
|
|
|
||
|
|
In order to achieve reproducible builds in U-Boot, timestamps that are defined
|
||
|
|
at build-time have to be somewhat eliminated. The SOURCE_DATE_EPOCH environment
|
||
|
|
variable allows setting a fixed value for those timestamps.
|
||
|
|
|
||
|
|
Simply by setting SOURCE_DATE_EPOCH to a fixed value, a number of targets can be
|
||
|
|
built reproducibly. This is the case for e.g. sunxi devices.
|
||
|
|
|
||
|
|
However, some other devices might need some more tweaks, especially regarding
|
||
|
|
the image generation tools.
|
||
|
|
|
||
|
|
Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
|
||
|
|
---
|
||
|
|
Makefile | 7 ++++---
|
||
|
|
README | 12 ++++++++++++
|
||
|
|
tools/default_image.c | 21 ++++++++++++++++++++-
|
||
|
|
3 files changed, 36 insertions(+), 4 deletions(-)
|
||
|
|
|
||
|
|
--- a/README
|
||
|
|
+++ b/README
|
||
|
|
@@ -2785,6 +2785,18 @@ Low Level (hardware related) configurati
|
||
|
|
that is executed before the actual U-Boot. E.g. when
|
||
|
|
compiling a NAND SPL.
|
||
|
|
|
||
|
|
+Reproducible builds
|
||
|
|
+-------------------
|
||
|
|
+
|
||
|
|
+In order to achieve reproducible builds, timestamps used in the U-Boot build
|
||
|
|
+process have to be set to a fixed value.
|
||
|
|
+
|
||
|
|
+This is done using the SOURCE_DATE_EPOCH environment variable.
|
||
|
|
+SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
|
||
|
|
+option for U-Boot or an environment variable in U-Boot.
|
||
|
|
+
|
||
|
|
+SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
|
||
|
|
+
|
||
|
|
Building the Software:
|
||
|
|
======================
|
||
|
|
|
||
|
|
--- a/tools/default_image.c
|
||
|
|
+++ b/tools/default_image.c
|
||
|
|
@@ -101,6 +101,9 @@ static void image_set_header (void *ptr,
|
||
|
|
struct mkimage_params *params)
|
||
|
|
{
|
||
|
|
uint32_t checksum;
|
||
|
|
+ char *source_date_epoch;
|
||
|
|
+ struct tm *time_universal;
|
||
|
|
+ time_t time;
|
||
|
|
|
||
|
|
image_header_t * hdr = (image_header_t *)ptr;
|
||
|
|
|
||
|
|
@@ -109,9 +112,25 @@ static void image_set_header (void *ptr,
|
||
|
|
sizeof(image_header_t)),
|
||
|
|
sbuf->st_size - sizeof(image_header_t));
|
||
|
|
|
||
|
|
+source_date_epoch = getenv("SOURCE_DATE_EPOCH");
|
||
|
|
+ if (source_date_epoch != NULL) {
|
||
|
|
+ time = (time_t) strtol(source_date_epoch, NULL, 10);
|
||
|
|
+
|
||
|
|
+ time_universal = gmtime(&time);
|
||
|
|
+ if (time_universal == NULL) {
|
||
|
|
+ fprintf(stderr, "%s: SOURCE_DATE_EPOCH is not valid\n",
|
||
|
|
+ __func__);
|
||
|
|
+ time = 0;
|
||
|
|
+ } else {
|
||
|
|
+ time = mktime(time_universal);
|
||
|
|
+ }
|
||
|
|
+ } else {
|
||
|
|
+ time = sbuf->st_mtime;
|
||
|
|
+ }
|
||
|
|
+
|
||
|
|
/* Build new header */
|
||
|
|
image_set_magic (hdr, IH_MAGIC);
|
||
|
|
- image_set_time (hdr, sbuf->st_mtime);
|
||
|
|
+ image_set_time(hdr, time);
|
||
|
|
image_set_size (hdr, sbuf->st_size - sizeof(image_header_t));
|
||
|
|
image_set_load (hdr, params->addr);
|
||
|
|
image_set_ep (hdr, params->ep);
|