diff options
Diffstat (limited to 'tools/mkimage/patches/090-reproducible-SOURCE_DATE_EPOCH.patch')
| -rw-r--r-- | tools/mkimage/patches/090-reproducible-SOURCE_DATE_EPOCH.patch | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/tools/mkimage/patches/090-reproducible-SOURCE_DATE_EPOCH.patch b/tools/mkimage/patches/090-reproducible-SOURCE_DATE_EPOCH.patch new file mode 100644 index 0000000000..c238fd62ed --- /dev/null +++ b/tools/mkimage/patches/090-reproducible-SOURCE_DATE_EPOCH.patch @@ -0,0 +1,82 @@ +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 +@@ -4928,6 +4928,18 @@ within that device. + normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the + virtual address in NOR flash. + ++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 +@@ -89,6 +89,9 @@ static void image_set_header(void *ptr, + 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; + +@@ -97,9 +100,25 @@ 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, params->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); |