Merge pull request #57 from bdpdx/bdpdx/add-hash-with-bytes-methods

Add methods to get the hash of a byte array

Author: itinance

README.md

@@ -29,7 +29,7 @@ pod install
 Import the lib into your project:
 
 ```javascript
-import { sha256 } from 'react-native-sha256';
+import { sha256, sha256Bytes } from 'react-native-sha256';
 ```
 
 Build a sha256-hash:
@@ -40,6 +40,15 @@ sha256("Test").then( hash => {
 })
 ```
 
+```javascript
+const message = new Uint8Array(8);
+const bytes = Array.from(message);
+
+sha256Bytes(message).then( hash => {
+    console.log(hash);
+})
+```
+
 # File-Hashes
 
 If you need to calculate SHA-256 hashes from a file, use this method of react-native-fs:

android/src/main/java/com/sha256lib/Sha256Module.java

@@ -4,6 +4,7 @@
 import com.facebook.react.bridge.ReactApplicationContext;
 import com.facebook.react.bridge.ReactContextBaseJavaModule;
 import com.facebook.react.bridge.ReactMethod;
+import com.facebook.react.bridge.ReadableArray;
 import com.facebook.react.bridge.Callback;
 import com.facebook.react.bridge.Promise;
 
@@ -28,13 +29,29 @@ public String getName() {
     return "sha256Lib";
   }
 
+  private static byte[] readableArrayToByteArray(ReadableArray readableArray) {
+      byte[] arr = new byte[readableArray.size()];
+      for (int i = 0; i < readableArray.size(); ++i) {
+          arr[i] = (byte) readableArray.getInt(i);
+      }
+
+      return arr;
+  }
+
   String buildHash(final String toHash, final String algo, final Integer length) throws NoSuchAlgorithmException, UnsupportedEncodingException {
     MessageDigest md = MessageDigest.getInstance(algo);
     md.update(toHash.getBytes("UTF-8"));
     byte[] digest = md.digest();
     return String.format("%0" + length.toString() + "x", new java.math.BigInteger(1, digest));
   }
 
+  String buildHashWithBytes(final ReadableArray toHash, final String algo, final Integer length) throws NoSuchAlgorithmException, UnsupportedEncodingException {
+    MessageDigest md = MessageDigest.getInstance(algo);
+    byte[] arr = Sha256Module.readableArrayToByteArray(toHash);
+    md.update(arr);
+    byte[] digest = md.digest();
+    return String.format("%0" + length.toString() + "x", new java.math.BigInteger(1, digest));
+  }
 
   @ReactMethod
   public void sha256(final String toHash, Promise promise) {
@@ -50,6 +67,20 @@ public void sha256(final String toHash, Promise promise) {
       }
   }
 
+  @ReactMethod
+  public void sha256Bytes(final ReadableArray toHash, Promise promise) {
+      try {
+          String hash = buildHashWithBytes(toHash, "SHA-256", 64);
+          promise.resolve(hash);
+      } catch (NoSuchAlgorithmException e) {
+          e.printStackTrace();
+          promise.reject("sha256", e.getMessage());
+      } catch (UnsupportedEncodingException e) {
+          e.printStackTrace();
+          promise.reject("sha256", e.getMessage());
+      }
+  }
+
   @ReactMethod
   public void sha1(final String toHash, Promise promise) {
       try {
@@ -64,4 +95,18 @@ public void sha1(final String toHash, Promise promise) {
       }
   }
 
+  @ReactMethod
+  public void sha1Bytes(final ReadableArray toHash, Promise promise) {
+      try {
+          String hash = buildHashWithBytes(toHash, "SHA-1", 40);
+          promise.resolve(hash);
+      } catch (NoSuchAlgorithmException e) {
+          e.printStackTrace();
+          promise.reject("sha1", e.getMessage());
+      } catch (UnsupportedEncodingException e) {
+          e.printStackTrace();
+          promise.reject("sha1", e.getMessage());
+      }
+  }
+
 }

ios/sha256.m

@@ -32,6 +32,31 @@ - (NSString*) calcHash: (NSString*) subject withDigestFunction: (DIGEST_FUNCTION
     return ret;
 }
 
+- (NSString*) calcHashWithBytes: (NSArray *) subject withDigestFunction: (DIGEST_FUNCTION) digest withDigestLength: (int) digestLength {
+    NSUInteger count = [subject count];
+    unsigned char *array = (unsigned char *) malloc(count);
+
+    if (array == nil) return nil;
+
+    for (int i = 0; i < count; ++i) {
+        array[i] = [[subject objectAtIndex: i] unsignedCharValue];
+    }
+
+    unsigned char result[digestLength];
+
+    digest(array, count, result);
+
+    free(array);
+
+    NSMutableString *ret = [NSMutableString stringWithCapacity:digestLength * 2];
+    for(int i = 0; i < digestLength; i++)
+    {
+        [ret appendFormat:@"%02x",result[i]];
+    }
+
+    return ret;
+}
+
 RCT_EXPORT_METHOD(sha1: (NSString *) data
                   resolver: (RCTPromiseResolveBlock) resolve
                   rejecter: (RCTPromiseRejectBlock) reject)
@@ -41,6 +66,20 @@ - (NSString*) calcHash: (NSString*) subject withDigestFunction: (DIGEST_FUNCTION
     resolve(ret);
 }
 
+RCT_EXPORT_METHOD(sha1Bytes: (NSArray *) data
+                  resolver: (RCTPromiseResolveBlock) resolve
+                  rejecter: (RCTPromiseRejectBlock) reject)
+
+{
+    NSString *ret = [self calcHashWithBytes:data withDigestFunction:CC_SHA1 withDigestLength: CC_SHA1_DIGEST_LENGTH];
+
+    if (ret) {
+        resolve(ret);
+    } else {
+        reject(@"error", @"out of memory", nil);
+    }
+}
+
 RCT_EXPORT_METHOD(sha256: (NSString *) data
                   resolver: (RCTPromiseResolveBlock) resolve
                   rejecter: (RCTPromiseRejectBlock) reject)
@@ -50,4 +89,18 @@ - (NSString*) calcHash: (NSString*) subject withDigestFunction: (DIGEST_FUNCTION
     resolve(ret);
 }
 
+RCT_EXPORT_METHOD(sha256Bytes: (NSArray *) data
+                  resolver: (RCTPromiseResolveBlock) resolve
+                  rejecter: (RCTPromiseRejectBlock) reject)
+
+{
+    NSString *ret = [self calcHashWithBytes:data withDigestFunction:CC_SHA256 withDigestLength: CC_SHA256_DIGEST_LENGTH];
+
+    if (ret) {
+        resolve(ret);
+    } else {
+        reject(@"error", @"out of memory", nil);
+    }
+}
+
 @end

sha256.d.ts

@@ -1,4 +1,6 @@
 declare module 'react-native-sha256' {
     export const sha1: (input: string) => Promise<string>;
+    export const sha1Bytes: (input: Array) => Promise<string>;
     export const sha256: (input: string) => Promise<string>;
+    export const sha256Bytes: (input: Array) => Promise<string>;
 }

sha256.js

@@ -12,6 +12,14 @@ export function sha256(data: string) {
   return sha256Lib.sha256(data);
 }
 
+export function sha256Bytes(data: Array) {
+  return sha256Lib.sha256Bytes(data);
+}
+ 
 export function sha1(data: string) {
   return sha256Lib.sha1(data);
 }
+
+export function sha1Bytes(data: Array) {
+  return sha256Lib.sha1Bytes(data);
+}