Como modificar um ISO de instalação e mantê-lo inicializável?

Eu sei que tem havido algumas perguntas semelhantes, mas elas não são específicas o suficiente.

Eu tenho um ISO de instalação do Windows 10 x64 e estou tentando extrair os arquivos fazer algumas modificações e depois fazer um novo ISO dos arquivos extraídos/modificados.

Basicamente funciona bem, mas o problema é que não consigo descobrir como torná-lo inicializável UEFI novamente (no modo legado/BIOS ele inicializa bem).

Eu passei por inúmeras postagens seguindo instruções sobre como fazer isso, mas nenhuma delas funcionou para o meu Windows 10 ISO. A maioria dessas postagens menciona apenas versões mais antigas do Windows e aquelas que mencionam o Windows 10 não especificam se conseguiram funcionar com uma versão x64 atual e se conseguiram inicializar UEFI a partir dela. (Provavelmente não, porque certamente não funciona para mim.)

Acabei tentando replicar a saída de isoinfo -d -i ./windows10.isoe dumpet -i ./windows10.isoo máximo que pude.

E isso é o mais próximo que consegui: (Edit: Atualizado -eltorito-alt-bootconforme sugerido pela telcoM)

ISO original (isoinfo):

$ isoinfo -d -i ./original.iso
CD-ROM is in ISO 9660 format
System id: 
Volume id: CCCOMA_X64FRE_EN-US_DV9
Volume set id: CCCOMA_X64FRE_EN-US_DV9
Publisher id: MICROSOFT CORPORATION
Data preparer id: MICROSOFT CORPORATION, ONE MICROSOFT WAY, REDMOND WA 98052, (425) 882-8080
Application id: CDIMAGE 2.56 (01/01/2005 TM)
Copyright File id: 
Abstract File id: 
Bibliographic File id: 
Volume set size is: 1
Volume set sequence number is: 1
Logical block size is: 2048
Volume size is: 2411879
El Torito VD version 1 found, boot catalog is in sector 22
NO Joliet present
NO Rock Ridge present
Eltorito validation header:
    Hid 1
    Arch 0 (x86)
    ID 'Microsoft Corporation'
    Key 55 AA
    Eltorito defaultboot header:
        Bootid 88 (bootable)
        Boot media 0 (No Emulation Boot)
        Load segment 0
        Sys type 0
        Nsect 8
        Bootoff 202 514

ISO modificado (isoinfo):

$ isoinfo -d -i ./modified.iso
CD-ROM is in ISO 9660 format
System id: 
Volume id: CCCOMA_X64FRE_EN-US_DV9
Volume set id: CCCOMA_X64FRE_EN-US_DV9
Publisher id: Microsoft Corporation
Data preparer id: MICROSOFT CORPORATION, ONE MICROSOFT WAY, REDMOND WA 98052, (425) 882-8080
Application id: CDIMAGE 2.56 (01/01/2005 TM)
Copyright File id: 
Abstract File id: 
Bibliographic File id: 
Volume set size is: 1
Volume set sequence number is: 1
Logical block size is: 2048
Volume size is: 2411275
El Torito VD version 1 found, boot catalog is in sector 1506
NO Joliet present
NO Rock Ridge present
Eltorito validation header:
    Hid 1
    Arch 0 (x86)
    ID 'Microsoft Corporation'
    Key 55 AA
    Eltorito defaultboot header:
        Bootid 88 (bootable)
        Boot media 0 (No Emulation Boot)
        Load segment 0
        Sys type 0
        Nsect 8
        Bootoff 8CD 2253

Diferença entre as saídas isoinfo acima:

$ diff <(isoinfo -i ./original.iso) <(isoinfo -i ./modified.iso)
5c5
< Publisher id: MICROSOFT CORPORATION
---
> Publisher id: Microsoft Corporation
14,15c14,15
< Volume size is: 2411879
< El Torito VD version 1 found, boot catalog is in sector 22
---
> Volume size is: 2411275
> El Torito VD version 1 found, boot catalog is in sector 1506
29c29
<         Bootoff 202 514
---
>         Bootoff 8CD 2253

ISO original (dump):

$ dumpet -i ./original.iso
Validation Entry:
        Header Indicator: 0x01 (Validation Entry)
        PlatformId: 0x00 (80x86)
        ID: "Microsoft Corporation"
        Checksum: 0x494c
        Key bytes: 0x55aa
Boot Catalog Default Entry:
        Entry is bootable
        Boot Media emulation type: no emulation
        Media load segment: 0x0 (0000:7c00)
        System type: 0 (0x00)
        Load Sectors: 8 (0x0008)
        Load LBA: 514 (0x00000202)
Section Header Entry:
        Header Indicator: 0x91 (Final Section Header Entry)
        PlatformId: 0xef (EFI)
        Section Entries: 1
        ID: ""
Boot Catalog Section Entry:
        Entry is bootable
        Boot Media emulation type: no emulation
        Media load address: 0 (0x0000)
        System type: 0 (0x00)
        Load Sectors: 1 (0x0001)
        Load LBA: 516 (0x00000204)

ISO modificado (despejo):

$ dumpet -i ./modified.iso 
Validation Entry:
        Header Indicator: 0x01 (Validation Entry)
        PlatformId: 0x00 (80x86)
        ID: "Microsoft Corporation"
        Checksum: 0x494c
        Key bytes: 0x55aa
Boot Catalog Default Entry:
        Entry is bootable
        Boot Media emulation type: no emulation
        Media load segment: 0x0 (0000:7c00)
        System type: 0 (0x00)
        Load Sectors: 8 (0x0008)
        Load LBA: 2253 (0x000008cd)
Section Header Entry:
        Header Indicator: 0x91 (Final Section Header Entry)
        PlatformId: 0xef (EFI)
        Section Entries: 1
        ID: ""
Boot Catalog Section Entry:
        Entry is bootable
        Boot Media emulation type: no emulation
        Media load address: 0 (0x0000)
        System type: 0 (0x00)
        Load Sectors: 2984 (0x0ba8)
        Load LBA: 1507 (0x000005e3)

Diferença entre as saídas do dumpet acima:

$ diff <(dumpet -i ./original.iso) <(dumpet -i ./modified.iso)
13c13
<       Load LBA: 514 (0x00000202)
---
>       Load LBA: 2253 (0x000008cd)
24,25c24,25
<       Load Sectors: 1 (0x0001)
<       Load LBA: 516 (0x00000204)
---
>       Load Sectors: 2984 (0x0ba8)
>       Load LBA: 1507 (0x000005e3)

Eu escrevi um script para reproduzir completamente o problema com o mesmo ISO que estou usando:

#!/usr/bin/env bash

##################################
# Download the Windows 10 x64 ISO

WIN10_IMG_DESTINATION="./windows.iso"
WIN10_IMG_ARCH="x64"

if [ ! -f "${WIN10_IMG_DESTINATION}" ]; then
    if [[ "$WIN10_IMG_ARCH" == "x86" ]] || [[ "$WIN10_IMG_ARCH" == "i386" ]] ; then
        echo "Retrieving the x86 Windows 10 iso URL..."
        WINDOWS_10_ISO_URL=$(curl -LsI -o /dev/null -w %{url_effective} "https://windows101tricks.com/1903-iso-32")
    else
        echo "Retrieving the x64 Windows 10 iso URL..."
        WINDOWS_10_ISO_URL=$(curl -LsI -o /dev/null -w %{url_effective} "https://windows101tricks.com/1903-iso-64")
    fi

    echo "Making sure the URL comes from a trusted Microsoft (sub)domain..."
    if [[ $WINDOWS_10_ISO_URL == https://software-download.microsoft.com/* ]] ; then
        echo "Downloading the Windows 10 installation iso..."
        wget "$WINDOWS_10_ISO_URL" -O "$WIN10_IMG_DESTINATION"
    else
        echo "URL validation failed. Please download the Windows 10 iso manually."
        exit 1
    fi
else
    echo "Windows 10 iso already exists. Skipping download..."
fi
#
##################################



# Variable containing the path to the windows.iso
WIN10_IMG="$WIN10_IMG_DESTINATION"

TMP="./tmp"
ISO_FILES="${TMP}/iso-files"
ISO_MP="${TMP}/iso-mountpoint"

# Remove ./tmp if it already exists, then create ./tmp/iso-files and ./tmp/iso-mountpoint
rm -rf "${TMP}"
mkdir -p "${ISO_FILES}"
mkdir -p "${ISO_MP}"
# Extract the files fromt he ISO to ./tmp/iso-files
sudo mount -t udf "${WIN10_IMG}" "${ISO_MP}"
sudo cp -Rva ${ISO_MP}/* "${ISO_FILES}"
sudo umount "${ISO_MP}"

# Make modifications to the Windows ISO
#BOOT_DIR="${ISO_FILES}/efi/microsoft/boot"
#sudo mv "${BOOT_DIR}/cdboot.efi" "${BOOT_DIR}/tmp.efi"
#sudo mv "${BOOT_DIR}/cdboot_noprompt.efi" "${BOOT_DIR}/cdboot.efi"
#sudo mv "${BOOT_DIR}/tmp.efi" "${BOOT_DIR}/cdboot_noprompt.efi"

# Extract the boot.img (didn't help at all)
#BOOT_SECTOR_LENGTH="$(isoinfo -d -i "${WIN10_IMG}" | grep "Nsect " | grep -o "[^ ]*$")"
#STARTING_SECTOR="$(isoinfo -d -i ./vm-files/windows10.iso | grep "Bootoff " | grep -o "[^ ]*$")"
#dd if="${WIN10_IMG}" of="${ISO_FILES}/boot.img" bs=2048 count="${BOOT_SECTOR_LENGTH}" skip="${STARTING_SECTOR}"


# Extract boot load segment address and size
BOOT_LOAD_SEG="$(dumpet -i "${WIN10_IMG}" | grep "Media load segment: " | cut -d ':' -f2 | cut -d ' ' -f2)"
BOOT_LOAD_SIZE="$(dumpet -i "${WIN10_IMG}" | grep "Load Sectors: " | grep -o "[^:]*$" | cut -d ' ' -f2 | head -1)"

# Extract meta data :
SYSTEM_ID="$(isoinfo -d -i "${WIN10_IMG}" | grep "System id: " | cut -d ' ' -f3-)"
VOLUME_ID="$(isoinfo -d -i "${WIN10_IMG}" | grep "Volume id: " | cut -d ' ' -f3-)"
VOLUME_SET_ID="$(isoinfo -d -i "${WIN10_IMG}" | grep "Volume set id: " | cut -d ' ' -f4-)"
#PUBLISHER_ID="$(isoinfo -d -i "${WIN10_IMG}" | grep "Publisher id: " | cut -d ' ' -f3-)" # Always uppercase
PUBLISHER_ID="$(isoinfo -d -i "${WIN10_IMG}" | grep "ID '" | cut -d "'" -f2)"
DATA_PREPARER_ID="$(isoinfo -d -i "${WIN10_IMG}" | grep "Data preparer id: " | cut -d ' ' -f4-)"
APPLICATION_ID="$(isoinfo -d -i "${WIN10_IMG}" | grep "Application id: " | cut -d ' ' -f3-)"
COPYRIGHT_FILE_ID="$(isoinfo -d -i "${WIN10_IMG}" | grep "Copyright file id: " | cut -d ' ' -f4-)"
ABSTRACT_FILE_ID="$(isoinfo -d -i "${WIN10_IMG}" | grep "Abstract file id: " | cut -d ' ' -f4-)"
BIBLIOGRAPHIC_FILE_ID="$(isoinfo -d -i "${WIN10_IMG}" | grep "Bibliographic file id: " | cut -d ' ' -f4-)"

# Create a new ISO image using mkisofs
# (.mkisofsrc is necessary, because some options are not available on the cli directly)
rm ".mkisofsrc"
echo "APPI=${APPLICATION_ID}" >> ".mkisofsrc"
echo "COPY=${COPYRIGHT_FILE_ID}" >> ".mkisofsrc"
echo "ABST=${ABSTRACT_FILE_ID}" >> ".mkisofsrc"
echo "BIBL=${BIBLIOGRAPHIC_FILE_ID}" >> ".mkisofsrc"
echo "PREP=${DATA_PREPARER_ID}" >> ".mkisofsrc"
echo "PUBL=${PUBLISHER_ID}" >> ".mkisofsrc"
echo "SYSI=${SYSTEM_ID}" >> ".mkisofsrc"
echo "VOLI=${VOLUME_ID}" >> ".mkisofsrc"
echo "VOLS=${VOLUME_SET_ID}" >> ".mkisofsrc"

sudo rm "${WIN10_IMG}.tmp.iso"
sudo mkisofs \
  -no-emul-boot \
  -b boot/etfsboot.com \
  -boot-load-seg "${BOOT_LOAD_SEG}" \
  -boot-load-size "${BOOT_LOAD_SIZE}" \
  -eltorito-alt-boot \
  -e efi/boot/bootx64.efi \
  -no-emul-boot \
  -iso-level 2 \
  -boot-info-table \
  -udf \
  -D \
  -N \
  -relaxed-filenames \
  -allow-lowercase \
  -o "${WIN10_IMG}.tmp.iso" \
  "${ISO_FILES}"

rm ".mkisofsrc"


# Print the variables that we gathered
echo
echo "Extracted meta data (form original image):"
echo "BOOT_LOAD_SEG: ${BOOT_LOAD_SEG}"
echo "BOOT_LOAD_SIZE: ${BOOT_LOAD_SIZE}"
echo "-------"
echo "SYSTEM_ID: ${SYSTEM_ID}"
echo "VOLUME_ID: ${VOLUME_ID}"
echo "VOLUME_SET_ID: ${VOLUME_SET_ID}"
echo "PUBLISHER_ID: ${PUBLISHER_ID}"
echo "DATA_PREPARER_ID: ${DATA_PREPARER_ID}"
echo "APPLICATION_ID: ${APPLICATION_ID}"
echo "COPYRIGHT_FILE_ID: ${COPYRIGHT_FILE_ID}"
echo "ABSTRACT_FILE_ID: ${ABSTRACT_FILE_ID}"
echo "BIBLIOGRAPHIC_FILE_ID: ${BIBLIOGRAPHIC_FILE_ID}"

# Show difference between new and old image as reported by isoinfo
echo
echo "-------------- isoinfo diff -----------------"
diff <(isoinfo -d -i "${WIN10_IMG}") <(isoinfo -d -i "${WIN10_IMG}.tmp.iso")

# Show difference between new and old image as reported by dumpet
echo
echo " -------------- dumpet diff -----------------"
diff <(dumpet -i "${WIN10_IMG}") <(dumpet -i "${WIN10_IMG}.tmp.iso")


# Overwrite the original ISO with the new one
#sudo rm "${WIN10_IMG}"
#sudo mv "${WIN10_IMG}.tmp.iso" "${WIN10_IMG}"