diff options
| -rw-r--r-- | Makefile | 7 | ||||
| -rw-r--r-- | README | 12 | ||||
| -rw-r--r-- | tools/default_image.c | 21 |
3 files changed, 36 insertions, 4 deletions
@@ -1230,9 +1230,10 @@ define filechk_version.h endef define filechk_timestamp.h - (LC_ALL=C date +'#define U_BOOT_DATE "%b %d %C%y"'; \ - LC_ALL=C date +'#define U_BOOT_TIME "%T"'; \ - LC_ALL=C date +'#define U_BOOT_TZ "%z"') + (SOURCE_DATE="$${SOURCE_DATE_EPOCH:+@$$SOURCE_DATE_EPOCH}"; \ + LC_ALL=C date -u -d "$${SOURCE_DATE:-now}" +'#define U_BOOT_DATE "%b %d %C%y"'; \ + LC_ALL=C date -u -d "$${SOURCE_DATE:-now}" +'#define U_BOOT_TIME "%T"'; \ + LC_ALL=C date -u -d "$${SOURCE_DATE:-now}" +'#define U_BOOT_TZ "%z"' ) endef $(version_h): include/config/uboot.release FORCE @@ -5081,6 +5081,18 @@ This firmware often needs to be loaded during U-Boot booting. - CONFIG_SYS_MEM_TOP_HIDE_MIN Define minimum DDR size to be hided from top of the DDR memory +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: ====================== diff --git a/tools/default_image.c b/tools/default_image.c index cf5c0d4393..18940af5b5 100644 --- a/tools/default_image.c +++ b/tools/default_image.c @@ -88,6 +88,9 @@ static void image_set_header(void *ptr, struct stat *sbuf, int ifd, struct image_tool_params *params) { uint32_t checksum; + char *source_date_epoch; + struct tm *time_universal; + time_t time; image_header_t * hdr = (image_header_t *)ptr; @@ -96,9 +99,25 @@ static void image_set_header(void *ptr, struct stat *sbuf, int ifd, 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); |
