Utils testing for EvaluatePolynomial; README, and documentation

Author: cipherboy

Contributors.md

@@ -0,0 +1,2 @@
+Contributors:
+    Alexander Scheel - [email protected]

README.md

@@ -1,3 +1,21 @@
-# sssa-golang
+# sssaas-golang
+An implementation of Shamir's Secret Sharing Algorithm in Go  
 
-sssa-golang
+    Copyright (C) 2015 Alexander Scheel, Joel May, Matthew Burket  
+    See Contributors.md for a complete list of contributors.  
+    Licensed under the MIT License.  
+
+## Usage
+Note: this library is for a pure implementation of SSS in Go;
+if you are looking for the API Library for SSSaaS, look [here](https://github.com/SSSAAS/sssaas-golang).
+
+    sssa.create(minimum int, shares int, raw string) - creates a set of shares
+
+    sssa.combine(shares []string) - combines shares into secret
+
+For more detailed documentation, check out docs/sssa.md
+
+## Contributing
+We welcome pull requests, issues, security advice on this library, or other contributions you feel are necessary. Feel free to open an issue to discuss any questions you have about this library.
+
+For security issues, send a GPG-encrypted email to <[email protected]> with public key [0xBDC5F518A973035E](https://pgp.mit.edu/pks/lookup?op=vindex&search=0xBDC5F518A973035E).

docs/safeprime.txt

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+99995644905598542077721161034987774965417302630805822064337798850767846245779

docs/sssa.md

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+# SSSA - Ruby
+## Constants
+    prime = 99995644905598542077721161034987774965417302630805822064337798850767846245779
+        Safe Prime; big.Int
+
+## Functions
+    create(minimum int, number int, raw string)
+        minimum - number of shares required to recreate the secret
+        number - total number of shares to generate
+        raw - secret to protect, as a string
+
+        returns shares as an array of base64 strings of variable length
+            dependent on the size of the raw secret
+
+    combine(shares []string)
+        shares - array of base64 strings returned by create function
+
+        returns a string of secret
+            note: this string can be ill-formatted utf8 potentially, if the
+            minimum number of shares was not met

utils_test.go

@@ -70,3 +70,29 @@ func TestModInverse(t *testing.T) {
 		}
 	}
 }
+
+func TestEvaluatePolynomial(t *testing.T) {
+	values := [][][]*big.Int {
+		[][]*big.Int{
+			[]*big.Int{big.NewInt(20), big.NewInt(21), big.NewInt(42),},
+			[]*big.Int{big.NewInt(0)},
+		},
+		[][]*big.Int{
+			[]*big.Int{big.NewInt(0), big.NewInt(0), big.NewInt(0),},
+			[]*big.Int{big.NewInt(4),},
+		},
+		[][]*big.Int{
+			[]*big.Int{big.NewInt(1), big.NewInt(2), big.NewInt(3), big.NewInt(4), big.NewInt(5),},
+			[]*big.Int{big.NewInt(10),},
+		},
+	}
+
+	actual := []*big.Int{big.NewInt(20), big.NewInt(0), big.NewInt(54321)}
+
+	for i := range(values) {
+		result := evaluatePolynomial(values[i][0], values[i][1][0])
+		if result.Cmp(actual[i]) != 0 {
+			t.Fatalf("Fatal: EvaluatePolynomial[%v] failed\nExpected: %v; Got: %v\n", i, actual[i], result)
+		}
+	}
+}