From 500a8bb751f05e8170f74bed3f1363c3ed90f39a Mon Sep 17 00:00:00 2001
From: Sei Lisa <sei-lisa@email.fake>
Date: Fri, 3 Feb 2023 21:48:33 +0100
Subject: [PATCH] llHMAC implementation (without importing hmac)

---
 lslopt/lslbasefuncs.py           | 37 +++++++++++++++++++++++++++++++-
 strutil.py                       |  5 +++--
 unit_tests/expr.suite/llhmac.lsl | 29 +++++++++++++++++++++++++
 unit_tests/expr.suite/llhmac.out |  3 +++
 unit_tests/expr.suite/llhmac.skp |  0
 5 files changed, 71 insertions(+), 3 deletions(-)
 create mode 100644 unit_tests/expr.suite/llhmac.lsl
 create mode 100644 unit_tests/expr.suite/llhmac.out
 create mode 100644 unit_tests/expr.suite/llhmac.skp

diff --git a/lslopt/lslbasefuncs.py b/lslopt/lslbasefuncs.py
index b42ddc6..b30b6aa 100644
--- a/lslopt/lslbasefuncs.py
+++ b/lslopt/lslbasefuncs.py
@@ -1307,6 +1307,41 @@ def llHash(s):
         hash = (hash * 65599 + ord(i)) & 0xFFFFFFFF
     return S32(hash)
 
+def llHMAC(pwd, data, alg):
+    pwd = bytewrap(uniwrap(fs(pwd)).encode('utf8'))
+    data = bytewrap(uniwrap(fs(data)).encode('utf8'))
+    alg = fs(alg)
+    hash = None
+    if alg == u'md5':
+        hash = hashlib.md5()
+    elif alg == u'sha1':
+        hash = hashlib.sha1()
+    elif alg == u'sha224':
+        hash = hashlib.sha224()
+    elif alg == u'sha256':
+        hash = hashlib.sha256()
+    elif alg == u'sha384':
+        hash = hashlib.sha384()
+    elif alg == u'sha512':
+        hash = hashlib.sha512()
+    if hash is None:
+        raise ELSLCantCompute  # we don't have info on how it behaves yet
+    # Calculate the HMAC here, to avoid requiring yet another module
+    if len(pwd) > hash.block_size:
+        tmp = hash.copy()
+        tmp.update(pwd)
+        pwd = bytewrap(tmp.digest())
+        del tmp
+    if len(pwd) < hash.block_size:
+        pwd += bytewrap(b'\x00') * (hash.block_size - len(pwd))
+    xorbytes = lambda a, b: bytewrap(x ^ y for (x, y) in zip(a, b))
+    ipadded = xorbytes(pwd, bytewrap(b'\x36') * hash.block_size)
+    opadded = xorbytes(pwd, bytewrap(b'\x5C') * hash.block_size)
+    ohash = hash.copy()
+    hash.update(ipadded + data)
+    ohash.update(opadded + hash.digest())
+    return b64encode(ohash.digest()).decode('utf8')
+
 def llInsertString(s, pos, src):
     s = fs(s)
     pos = fi(pos)
@@ -1316,7 +1351,7 @@ def llInsertString(s, pos, src):
 
 def llIntegerToBase64(x):
     x = fi(x)
-    return (b64encode(bytearray(((x>>24)&255, (x>>16)&255, (x>>8)&255, x&255)))
+    return (b64encode(bytewrap(((x>>24)&255, (x>>16)&255, (x>>8)&255, x&255)))
             .decode('utf8'))
 
 def llLinear2sRGB(v):
diff --git a/strutil.py b/strutil.py
index ba45189..7fcc8a3 100644
--- a/strutil.py
+++ b/strutil.py
@@ -23,14 +23,15 @@ codecs.register(lambda x: codecs.lookup('utf8') if x == 'cp65001' else None)
 
 import sys
 
+python2Narrow = False
 if sys.version_info.major >= 3:
     unicode = str
     unichr = chr
     xrange = range
     python3 = True
     python2 = False
-    python2Narrow = False
     uniwrap = unicode
+    bytewrap = bytes
 
     def str2u(s, enc=None):
         """Convert a native Python3 str to Unicode. This is a NOP."""
@@ -60,8 +61,8 @@ else:
     xrange = xrange
     python2 = True
     python3 = False
-    python2Narrow = False
     uniwrap = unicode
+    bytewrap = bytearray
 
     def str2u(s, enc=None):
         """Convert a native Python2 str to Unicode."""
diff --git a/unit_tests/expr.suite/llhmac.lsl b/unit_tests/expr.suite/llhmac.lsl
new file mode 100644
index 0000000..aa17e0b
--- /dev/null
+++ b/unit_tests/expr.suite/llhmac.lsl
@@ -0,0 +1,29 @@
+[ llHMAC("a", "b", "sha1")
+, llHMAC("-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----", "Hello, Avatar!", "sha1")
+]
diff --git a/unit_tests/expr.suite/llhmac.out b/unit_tests/expr.suite/llhmac.out
new file mode 100644
index 0000000..e54502e
--- /dev/null
+++ b/unit_tests/expr.suite/llhmac.out
@@ -0,0 +1,3 @@
+[ "ZleFVoaCOYbIdDYnMROXUgFMtgs="
+, "xK/3hcR1IVpVK9vftoztuVRGZFE="
+]
\ No newline at end of file
diff --git a/unit_tests/expr.suite/llhmac.skp b/unit_tests/expr.suite/llhmac.skp
new file mode 100644
index 0000000..e69de29