fastboot driver: repack vendor boot ramdisk
When a user issues `fastboot flash vendor_boot:foo ramdisk.img`, the fastboot driver
fetches the vendor_boot image from the device,
determines if `foo` is a valid vendor ramdisk fragment,
repacks a new vendor boot image, then
flash the vendor boot image back.
This requires vendor boot header V4.
As a convinent alias, `fastboot flash vendor_boot:default ramdisk.img`
flashes the whole vendor ramdisk image. This works on vendor boot header
V3 & 4.
Fixes: 173654501
Test: pass
Change-Id: I42b2483a736ea8aa9fd9372b960502a642934cdc
diff --git a/fastboot/fastboot.cpp b/fastboot/fastboot.cpp
index dacac97..94efeea 100644
--- a/fastboot/fastboot.cpp
+++ b/fastboot/fastboot.cpp
@@ -76,6 +76,7 @@
#include "udp.h"
#include "usb.h"
#include "util.h"
+#include "vendor_boot_img_utils.h"
using android::base::borrowed_fd;
using android::base::ReadFully;
@@ -1292,6 +1293,40 @@
do_for_partitions(partition, slot_override, fetch, false /* force slot */);
}
+// Return immediately if not flashing a vendor boot image. If flashing a vendor boot image,
+// repack vendor_boot image with an updated ramdisk. After execution, buf is set
+// to the new image to flash, and return value is the real partition name to flash.
+static std::string repack_ramdisk(const char* pname, struct fastboot_buffer* buf) {
+ std::string_view pname_sv{pname};
+
+ if (!android::base::StartsWith(pname_sv, "vendor_boot:") &&
+ !android::base::StartsWith(pname_sv, "vendor_boot_a:") &&
+ !android::base::StartsWith(pname_sv, "vendor_boot_b:")) {
+ return std::string(pname_sv);
+ }
+ if (buf->type != FB_BUFFER_FD) {
+ die("Flashing sparse vendor ramdisk image is not supported.");
+ }
+ if (buf->sz <= 0) {
+ die("repack_ramdisk() sees negative size: %" PRId64, buf->sz);
+ }
+ std::string partition(pname_sv.substr(0, pname_sv.find(':')));
+ std::string ramdisk(pname_sv.substr(pname_sv.find(':') + 1));
+
+ unique_fd vendor_boot(make_temporary_fd("vendor boot repack"));
+ uint64_t vendor_boot_size = fetch_partition(partition, vendor_boot);
+ auto repack_res = replace_vendor_ramdisk(vendor_boot, vendor_boot_size, ramdisk, buf->fd,
+ static_cast<uint64_t>(buf->sz));
+ if (!repack_res.ok()) {
+ die("%s", repack_res.error().message().c_str());
+ }
+
+ buf->fd = std::move(vendor_boot);
+ buf->sz = vendor_boot_size;
+ buf->image_size = vendor_boot_size;
+ return partition;
+}
+
static void do_flash(const char* pname, const char* fname) {
verbose("Do flash %s %s", pname, fname);
struct fastboot_buffer buf;
@@ -1302,7 +1337,8 @@
if (is_logical(pname)) {
fb->ResizePartition(pname, std::to_string(buf.image_size));
}
- flash_buf(pname, &buf);
+ std::string flash_pname = repack_ramdisk(pname, &buf);
+ flash_buf(flash_pname, &buf);
}
// Sets slot_override as the active slot. If slot_override is blank,