View Issue Details
| ID | Project | Category | View Status | Date Submitted | Last Update |
|---|---|---|---|---|---|
| 0000682 | file | General | public | 2025-09-09 17:37 | 2025-09-09 17:37 |
| Reporter | alip | Assigned To | |||
| Priority | normal | Severity | feature | Reproducibility | N/A |
| Status | new | Resolution | open | ||
| Summary | 0000682: Feature request: Recognize files encrypted by Syd sandbox | ||||
| Description | Hello dear kind people, I am Ali Polatel, an Exherbo Linux developer and the main author of Syd sandbox. I have written a patch for file(1) to recognize files encrypted by Syd. You may find it attached. I am also attaching an encrypted test file called test.crypt which has the plaintext "The meaning of life is 42.\n" and it is encrypted with the key "0ce20c69e248311f50f51bdea4feac01d063ee57e051de6af3b7477eff9df23a". Running patched file(1) on the file gives the following output: test.crypt: SYD encrypted file, version 3, AES-256-CTR; HMAC-SHA256:86daea48e958ce631d9209ad6ecf919037f7c17562eaecb57ece75d0c83c96be, IV:4fc988c179ade4e6754b785c7f29c111, ciphertext 27 bytes To decrypt the file you install syd with "cargo install syd --locked" (packaged on Alpine, Arch, Exherbo, Gentoo, but alpine version is a bit old) And use the syd-aes tool: alip@hex ~ $ tail -c +54 test.crypt | syd-aes -d -k${SYD_KEY} -i 4fc988c179ade4e6754b785c7f29c111 -t SYD-ENC The meaning of life is 42. alip@hex ~ $ There's no defined extension for this encrypted file yet. You may find documentation here: https://man.exherbo.org/syd.7.html#Crypt_Sandboxing The URL is also mentoned in the patch. The magic file "syd" is also attached separately, so you may quickly test with an unpatched file(1) using -m. Thank you for the wonderful software! May you be forever young! Best regards, Ali Polatel | ||||
| Tags | libmagic, magic, patch | ||||
|
|
0001-magic-recognize-syd-encrypted-files.patch (2,249 bytes)
From 113236754315de718857edea23d7aaa513bbe5cf Mon Sep 17 00:00:00 2001 From: Ali Polatel <alip@hexsys.org> Date: Tue, 9 Sep 2025 16:28:02 +0200 Subject: [PATCH] magic: recognize syd encrypted files Documentation: https://man.exherbo.org/syd.7.html#Crypt_Sandboxing Signed-off-by: Ali Polatel <alip@hexsys.org> --- magic/Magdir/syd | 37 +++++++++++++++++++++++++++++++++++++ magic/Makefile.am | 1 + 2 files changed, 38 insertions(+) create mode 100644 magic/Magdir/syd diff --git a/magic/Magdir/syd b/magic/Magdir/syd new file mode 100644 index 00000000..0203d6f8 --- /dev/null +++ b/magic/Magdir/syd @@ -0,0 +1,37 @@ +#------------------------------------------------------------------------------ +# $File: syd,v $ +# syd: file(1) magic for syd(1) encrypted files +# +# From: Ali Polatel <alip@chesswob.org> +# Documentation: https://man.exherbo.org/syd.7.html#Crypt_Sandboxing +# No defined extension yet; files are recognized by magic header only. +# +# Layout: +# 0..3 : "\x7fSYD" +# 4 : version byte (current API: 3) +# 5..36 : HMAC (32 bytes, SHA256) +# 37..52 : IV (16 bytes) +# 53.. : ciphertext (AES-256-CTR) +#------------------------------------------------------------------------------ + +# Header and version +0 string \x7fSYD SYD encrypted file +>4 ubyte x \b, version %u + +# Version 3: algorithm + HMAC/IV as hex blobs + ciphertext size +>>4 ubyte =3 \b, AES-256-CTR; HMAC-SHA256: +>>>5 belong x \b%08x +>>>9 belong x \b%08x +>>>13 belong x \b%08x +>>>17 belong x \b%08x +>>>21 belong x \b%08x +>>>25 belong x \b%08x +>>>29 belong x \b%08x +>>>33 belong x \b%08x +>>>37 belong x \b, IV:%08x +>>>41 belong x \b%08x +>>>45 belong x \b%08x +>>>49 belong x \b%08x +>>>-0 offset-53 x \b, ciphertext %llu bytes + +# End of syd diff --git a/magic/Makefile.am b/magic/Makefile.am index 0a99b836..49241d5b 100644 --- a/magic/Makefile.am +++ b/magic/Makefile.am @@ -304,6 +304,7 @@ $(MAGIC_FRAGMENT_DIR)/statistics \ $(MAGIC_FRAGMENT_DIR)/subtitle \ $(MAGIC_FRAGMENT_DIR)/sun \ $(MAGIC_FRAGMENT_DIR)/svf \ +$(MAGIC_FRAGMENT_DIR)/syd \ $(MAGIC_FRAGMENT_DIR)/sylk \ $(MAGIC_FRAGMENT_DIR)/symbos \ $(MAGIC_FRAGMENT_DIR)/sysex \ -- 2.51.0 syd (1,175 bytes)
#------------------------------------------------------------------------------ # $File: syd,v $ # syd: file(1) magic for syd(1) encrypted files # # From: Ali Polatel <alip@chesswob.org> # Documentation: https://man.exherbo.org/syd.7.html#Crypt_Sandboxing # No defined extension yet; files are recognized by magic header only. # # Layout: # 0..3 : "\x7fSYD" # 4 : version byte (current API: 3) # 5..36 : HMAC (32 bytes, SHA256) # 37..52 : IV (16 bytes) # 53.. : ciphertext (AES-256-CTR) #------------------------------------------------------------------------------ # Header and version 0 string \x7fSYD SYD encrypted file >4 ubyte x \b, version %u # Version 3: algorithm + HMAC/IV as hex blobs + ciphertext size >>4 ubyte =3 \b, AES-256-CTR; HMAC-SHA256: >>>5 belong x \b%08x >>>9 belong x \b%08x >>>13 belong x \b%08x >>>17 belong x \b%08x >>>21 belong x \b%08x >>>25 belong x \b%08x >>>29 belong x \b%08x >>>33 belong x \b%08x >>>37 belong x \b, IV:%08x >>>41 belong x \b%08x >>>45 belong x \b%08x >>>49 belong x \b%08x >>>-0 offset-53 x \b, ciphertext %llu bytes # End of syd |
| Date Modified | Username | Field | Change |
|---|---|---|---|
| 2025-09-09 17:37 | alip | New Issue | |
| 2025-09-09 17:37 | alip | Tag Attached: libmagic | |
| 2025-09-09 17:37 | alip | Tag Attached: magic | |
| 2025-09-09 17:37 | alip | Tag Attached: patch | |
| 2025-09-09 17:37 | alip | File Added: 0001-magic-recognize-syd-encrypted-files.patch | |
| 2025-09-09 17:37 | alip | File Added: test.crypt | |
| 2025-09-09 17:37 | alip | File Added: syd |
