2 files changed, 44 insertions(+), 23 deletions(-)

M sha/sha.lua
M sha/sha.test.lua

@@ 8,7 8,7 @@ local rotr = u32.rotr
 local shr = u32.shr
 local sum = u32.sum
 
-M.sha256 = {
+M.sha256 = setmetatable({
    H0 = {
       0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a,
       0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19,


@@ 32,21 32,15 @@ M.sha256 = {
    bsig1 = function(x) return rotr(x, 6) ~ rotr(x, 11) ~ rotr(x, 25) end,
    ssig0 = function(x) return rotr(x, 7) ~ rotr(x, 18) ~ shr(x, 3) end,
    ssig1 = function(x) return rotr(x, 17) ~ rotr(x, 19) ~ shr(x, 10) end,
-}
-
-function M.sha256.init(buf)
-   H = {}
-   for k, v in pairs(M.sha256.H0) do
-      H[k] = v
-   end
-
-   local buf = buf or ""
-   return {
-      H = H,
-      buf = buf,
-      L = #buf,
-   }
-end
+}, {
+   __call = function(L, ...)
+      local ctx = L.init()
+      for _, bs in ipairs({...}) do
+         ctx:update(bs)
+      end
+      return ctx:finalize()
+   end,
+})
 
 local function sha256_process_blocks(ctx)
    if #ctx.buf < 64 then


@@ 113,6 107,7 @@ function M.sha256.update(ctx, bs)
    ctx.buf = ctx.buf .. bs
    ctx.L = ctx.L + #bs
    sha256_process_blocks(ctx)
+   return ctx
 end
 
 function M.sha256.pad(buf, l)


@@ 143,4 138,22 @@ function M.sha256.finalize(ctx)
    return digest
 end
 
+function M.sha256.init(buf)
+   H = {}
+   for k, v in pairs(M.sha256.H0) do
+      H[k] = v
+   end
+
+   local buf = buf or ""
+   local ctx = {
+      H = H,
+      buf = buf,
+      L = #buf,
+      update = M.sha256.update,
+      finalize = M.sha256.finalize,
+   }
+   sha256_process_blocks(ctx)
+   return ctx
+end
+
 return M

@@ 7,17 7,25 @@ local F = require("fresh")
 local N = 100
 
 function test_sha256_empty()
-    local ctx = L.sha256.init()
-    local digest = L.sha256.finalize(ctx)
+    local digest = L.sha256.init():finalize()
     lu.assertEquals(H.encode(digest), "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855")
 end
 
 function test_sha256_foo()
-    local ctx = L.sha256.init("foo")
-    local digest = L.sha256.finalize(ctx)
+    local digest = L.sha256.init("foo"):finalize()
     lu.assertEquals(H.encode(digest), "2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae")
 end
 
+function test_sha256_foobar_1()
+    local digest = L.sha256.init("foo"):update("bar"):finalize()
+    lu.assertEquals(H.encode(digest), "c3ab8ff13720e8ad9047dd39466b3c8974e592c2fa383d4a3960714caef0c4f2")
+end
+
+function test_sha256_foobar_2()
+    local digest = L.sha256("foo", "bar")
+    lu.assertEquals(H.encode(digest), "c3ab8ff13720e8ad9047dd39466b3c8974e592c2fa383d4a3960714caef0c4f2")
+end
+
 function test_sha256_pad()
     msg = H.decode("6162636465")
     padded = L.sha256.pad(msg, #msg)


@@ 31,9 39,9 @@ function test_sha256_fresh()
         local bs2 = F.bytestring()
 
         local ctx = L.sha256.init(bs0)
-        L.sha256.update(ctx, bs1)
-        L.sha256.update(ctx, bs2)
-        local digest = L.sha256.finalize(ctx)
+        ctx:update(bs1)
+        ctx:update(bs2)
+        local digest = ctx:finalize()
 
         lu.assertEquals(H.encode(digest), H.encode(ref.openssl.sha256(bs0, bs1, bs2)))
         lu.assertEquals(H.encode(digest), H.encode(ref.rfc.sha256(bs0, bs1, bs2)))