Firmware

DH_SD-Mao-Rhea_Eng_P_Stream3_IVS_V2.422.0000.1.R.20161130.bin

Dahua firmware released Nov 30, 2016. May work with 25 devices, including CA-HZ2012T-S2, CA-HZ2023T-S2, CA-HZ2025T-S2.

Download

Permanent copy on the Internet Archive (item page)

Hardware IDs this firmware's installer accepts (25 devices).

Where these IDs come from

Install: the installer's device list (board families), 5 IDs, vendor General (not counted: a more specific list exists)
check.img: the device's own hardware check list, 25 IDs

Read from inside the firmware (dahua package (zip variant)).

Flash layout: 15 partitions, 9 written by this firmware

From the firmware's partition table (partitionV2.txt).

Partition	Start	End	Size	Image	Filesystem	Built
MinBoot	0x0	0x100000	1.0 MB	dhboot-min.bin.img	—	2017-06-23
U-Boot	0x200000	0x300000	1.0 MB	dhboot.bin.img	—	2017-06-23
hwid	0x300000	0x400000	1.0 MB	not written	—	—
updateflag	0x400000	0x500000	1.0 MB	not written	—	—
partition(ro)	0x500000	0x600000	1.0 MB	partition-x.cramfs.img	cramfs	2017-06-23
custom(ro)	0x600000	0x940000	3.3 MB	custom-x.squashfs.img	squashfs	2017-06-23
product(ro)	0x940000	0xc80000	3.3 MB	pd-x.squashfs.img	squashfs	2017-06-23
Kernel	0xc80000	0x1200000	5.5 MB	kernel.img	—	2017-06-23
romfs(ro)	0x1200000	0x1600000	4.0 MB	romfs-x.squashfs.img	squashfs	2017-08-28
web(ro)	0x1600000	0x1e00000	8.0 MB	web-x.squashfs.img	squashfs	2017-06-23
user(ro)	0x1e00000	0x3a80000	28.5 MB	user-x.squashfs.img	squashfs	2017-08-28
lens	0x7100000	0x7200000	1.0 MB	not written	—	—
syslog	0x7200000	0x7600000	4.0 MB	not written	ubi	—
config	0x7600000	0x7a00000	4.0 MB	not written	ubi	—
backup	0x7a00000	0x7e00000	4.0 MB	not written	ubi	—

Other files for much of the same hardware, from any vendor.