AFV

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Activation File Verification

AFV are activation files used for/by development unit, they follow this format
Below format is as parsed by firmware 1.692 or below, firmware 1.800 or later expect a newer AFV format.

# VITA/ActivationCode
# format_version=1
# code_num=2
# code_size=199
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa, 1546297725, ‭‭2082758400‬,          1, f32fe2cc3a6346714949b219e68391d13766e467053b265d110241c33c7d8e58d4466c84a9d2422511b11a450b34c6db270b51f55d5921ea50c7feb571675a88
bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb, 1546297725, ‭‭2082758400‬,          1, f32fe2cc3a6346714949b219e68391d149cadd26411291837b62c98ad5a7cd8b64dff1c0a224273c9de99327b3a5f6524db261536fe60f657056be94d0ee08d0

Syntax of the header is as follows:

Value Description
# VITA/ActivationCode MAGIC
# format_version=1 AFV format version
# code_num=2 Number of activation codes, can be incremented to add multiple devices per activation file
# code_size=199 Number of characters per code + 1
# extra_data_size=513 Only in later activation files using signatures (for firmware 2.10+)
# VITA/ActivationCode
# format_version=1
# code_num=1
# code_size=199
open_psid, start_date(epoch decimal), end_date(epoch decimal)‬, issue_no, encrypted_activation_token

Crafting an AFV file

Base token buffer

Build a 0x70 token buffer as follows:

Offset(h) 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F

00000000  61 63 74 00 01 00 00 00 01 00 00 00 7D A1 2A 5C  act.........}¡*\
00000010  00 5F 24 7C AA AA AA AA AA AA AA AA AA AA AA AA  ._$|ªªªªªªªªªªªª
00000020  AA AA AA AA 00 00 00 00 00 00 00 00 00 00 00 00  ªªªª............
00000030  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00000040  61 63 74 00 01 00 00 00 01 00 00 00 7D A1 2A 5C  act.........}¡*\
00000050  00 5F 24 7C AA AA AA AA AA AA AA AA AA AA AA AA  ._$|ªªªªªªªªªªªª
00000060  AA AA AA AA 00 00 00 00 00 00 00 00 00 00 00 00  ªªªª............
00000070  XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX  CMAC will be there

Macro Structure

Offset Size Description
0x00 0x30 Activation Data (as seen in act.dat)
0x30 0x10 Padding, zeroed
0x40 0x30 Encrypted Activation Data (in decrypted form), can be a 100% copy of the data from 0x0 to 0x30
0x70 0x10 CMAC of 0 thru 0x70

Detailed Structure

Offset Size Description
0x00 4 Magic "act\0"
0x04 4 Format version (always 0x1)
0x08 4 Issue No (increments for each activation, it needs to be higher than the current token/activation counter, you may need to keep incrementing it until it works, or use a higher value like 0x20)
0x0C 4 Start date (Unix time, hex, little-endian)
0x10 4 End date (Unix time, hex, little-endian)
0x14 0x10 OpenPSID
0x24 0x1C Padding
0x40 4 unk
0x45 1 set to 0x1 on later encrypted token (ignored on the vita side)
0x46 1 set to the first AID byte in later encrypted tokens (ignored on the vita side)
0x47 1 set to the second AID byte in later encrypted tokens (ignored on the vita side)

It is speculated that on later sony's own encrypted token bytes 0x05 to 0x07 (0x45 to 0x47 in the buffer) are set to avoid having the first encrypted CBC block data repeat across multiple devices. Those bytes are ignored by act_sm and can be all set to 0x00.

AES256-CMAC

Take the 0x70 first bytes of the base token buffer:

Offset(h) 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F

00000000  61 63 74 00 01 00 00 00 01 00 00 00 7D A1 2A 5C  act.........}¡*\
00000010  00 5F 24 7C AA AA AA AA AA AA AA AA AA AA AA AA  ._$|ªªªªªªªªªªªª
00000020  AA AA AA AA 00 00 00 00 00 00 00 00 00 00 00 00  ªªªª............
00000030  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00000040  61 63 74 00 01 00 00 00 01 00 00 00 7D A1 2A 5C  act.........}¡*\
00000050  00 5F 24 7C AA AA AA AA AA AA AA AA AA AA AA AA  ._$|ªªªªªªªªªªªª
00000060  AA AA AA AA 00 00 00 00 00 00 00 00 00 00 00 00  ªªªª............

Calculate the AES256-CMAC hash of this buffer using the following command:

openssl dgst -mac cmac -macopt cipher:aes-256-cbc -macopt hexkey:846D2DFD77D3C2E5F0E17EB18CC786928B881E2E17AE0CD8FDE88809D0D033C5 base_token_buffer.bin

For that particular buffer the return value is:

aes256_cmac(base_token_buffer.bin) = e555fe806c33978b4694af72b5597b1d

This 0x10 byte result must be written to offset 0x70.

Offset(h) 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F

00000000  61 63 74 00 01 00 00 00 01 00 00 00 7D A1 2A 5C  act.........}¡*\
00000010  00 5F 24 7C AA AA AA AA AA AA AA AA AA AA AA AA  ._$|ªªªªªªªªªªªª
00000020  AA AA AA AA 00 00 00 00 00 00 00 00 00 00 00 00  ªªªª............
00000030  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00000040  61 63 74 00 01 00 00 00 01 00 00 00 7D A1 2A 5C  act.........}¡*\
00000050  00 5F 24 7C AA AA AA AA AA AA AA AA AA AA AA AA  ._$|ªªªªªªªªªªªª
00000060  AA AA AA AA 00 00 00 00 00 00 00 00 00 00 00 00  ªªªª............
00000070  E5 55 FE 80 6C 33 97 8B 46 94 AF 72 B5 59 7B 1D  åUþ€l3—‹F”¯rµY{.

Intermediate Token

Create a 0x40 buffer using data of your previous buffer from 0x40 to 0x80:

Offset(h) 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F

00000000  61 63 74 00 01 00 00 00 01 00 00 00 7D A1 2A 5C  act.........}¡*\
00000010  00 5F 24 7C AA AA AA AA AA AA AA AA AA AA AA AA  ._$|ªªªªªªªªªªªª
00000020  AA AA AA AA 00 00 00 00 00 00 00 00 00 00 00 00  ªªªª............
00000030  E5 55 FE 80 6C 33 97 8B 46 94 AF 72 B5 59 7B 1D  åUþ€l3—‹F”¯rµY{.

Encrypt this 0x40 byte buffer with the following command:

openssl aes-256-cbc -in step2.bin -K 846D2DFD77D3C2E5F0E17EB18CC786928B881E2E17AE0CD8FDE88809D0D033C5 -iv C8A040662B10A1986A1894E94FBEFCF0 -e > intermediate_token.bin

Below is the result for that particular token:

Offset(h) 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F

00000000  F3 2F E2 CC 3A 63 46 71 49 49 B2 19 E6 83 91 D1  ó/âÌ:cFqII².惑Ñ
00000010  37 66 E4 67 05 3B 26 5D 11 02 41 C3 3C 7D 8E 58  7fäg.;&]..AÃ<}ŽX
00000020  D4 46 6C 84 A9 D2 42 25 11 B1 1A 45 0B 34 C6 DB  ÔFl„©ÒB%.±.E.4ÆÛ
00000030  27 0B 51 F5 5D 59 21 EA 50 C7 FE B5 71 67 5A 88  '.Qõ]Y!êPÇþµqgZˆ
00000040  77 06 44 05 52 64 1C 21 33 91 DB 1B 07 50 67 18  w.D.Rd.!3‘Û..Pg.

Final Token

Get the first 0x40 bytes of that encrypted buffer (disregard the last 0x10 bytes of CBC padding). That will be your final token.

Offset(h) 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F

00000000  F3 2F E2 CC 3A 63 46 71 49 49 B2 19 E6 83 91 D1  ó/âÌ:cFqII².惑Ñ
00000010  37 66 E4 67 05 3B 26 5D 11 02 41 C3 3C 7D 8E 58  7fäg.;&]..AÃ<}ŽX
00000020  D4 46 6C 84 A9 D2 42 25 11 B1 1A 45 0B 34 C6 DB  ÔFl„©ÒB%.±.E.4ÆÛ
00000030  27 0B 51 F5 5D 59 21 EA 50 C7 FE B5 71 67 5A 88  '.Qõ]Y!êPÇþµqgZˆ

Final AFV

You can now create your afv file as shown below:

# VITA/ActivationCode
# format_version=1
# code_num=1
# code_size=199
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa, 1546297725, ‭‭2082758400‬,          1, f32fe2cc3a6346714949b219e68391d13766e467053b265d110241c33c7d8e58d4466c84a9d2422511b11a450b34c6db270b51f55d5921ea50c7feb571675a88