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-rw-r--r--node_modules/public-encrypt/publicEncrypt.js95
1 files changed, 95 insertions, 0 deletions
diff --git a/node_modules/public-encrypt/publicEncrypt.js b/node_modules/public-encrypt/publicEncrypt.js
new file mode 100644
index 000000000..f1ce40461
--- /dev/null
+++ b/node_modules/public-encrypt/publicEncrypt.js
@@ -0,0 +1,95 @@
+var parseKeys = require('parse-asn1');
+var randomBytes = require('randombytes');
+var createHash = require('create-hash');
+var mgf = require('./mgf');
+var xor = require('./xor');
+var bn = require('bn.js');
+var withPublic = require('./withPublic');
+var crt = require('browserify-rsa');
+
+var constants = {
+ RSA_PKCS1_OAEP_PADDING: 4,
+ RSA_PKCS1_PADDIN: 1,
+ RSA_NO_PADDING: 3
+};
+
+module.exports = function publicEncrypt(public_key, msg, reverse) {
+ var padding;
+ if (public_key.padding) {
+ padding = public_key.padding;
+ } else if (reverse) {
+ padding = 1;
+ } else {
+ padding = 4;
+ }
+ var key = parseKeys(public_key);
+ var paddedMsg;
+ if (padding === 4) {
+ paddedMsg = oaep(key, msg);
+ } else if (padding === 1) {
+ paddedMsg = pkcs1(key, msg, reverse);
+ } else if (padding === 3) {
+ paddedMsg = new bn(msg);
+ if (paddedMsg.cmp(key.modulus) >= 0) {
+ throw new Error('data too long for modulus');
+ }
+ } else {
+ throw new Error('unknown padding');
+ }
+ if (reverse) {
+ return crt(paddedMsg, key);
+ } else {
+ return withPublic(paddedMsg, key);
+ }
+};
+
+function oaep(key, msg){
+ var k = key.modulus.byteLength();
+ var mLen = msg.length;
+ var iHash = createHash('sha1').update(new Buffer('')).digest();
+ var hLen = iHash.length;
+ var hLen2 = 2 * hLen;
+ if (mLen > k - hLen2 - 2) {
+ throw new Error('message too long');
+ }
+ var ps = new Buffer(k - mLen - hLen2 - 2);
+ ps.fill(0);
+ var dblen = k - hLen - 1;
+ var seed = randomBytes(hLen);
+ var maskedDb = xor(Buffer.concat([iHash, ps, new Buffer([1]), msg], dblen), mgf(seed, dblen));
+ var maskedSeed = xor(seed, mgf(maskedDb, hLen));
+ return new bn(Buffer.concat([new Buffer([0]), maskedSeed, maskedDb], k));
+}
+function pkcs1(key, msg, reverse){
+ var mLen = msg.length;
+ var k = key.modulus.byteLength();
+ if (mLen > k - 11) {
+ throw new Error('message too long');
+ }
+ var ps;
+ if (reverse) {
+ ps = new Buffer(k - mLen - 3);
+ ps.fill(0xff);
+ } else {
+ ps = nonZero(k - mLen - 3);
+ }
+ return new bn(Buffer.concat([new Buffer([0, reverse?1:2]), ps, new Buffer([0]), msg], k));
+}
+function nonZero(len, crypto) {
+ var out = new Buffer(len);
+ var i = 0;
+ var cache = randomBytes(len*2);
+ var cur = 0;
+ var num;
+ while (i < len) {
+ if (cur === cache.length) {
+ cache = randomBytes(len*2);
+ cur = 0;
+ }
+ num = cache[cur++];
+ if (num) {
+ out[i++] = num;
+ }
+ }
+ return out;
+} \ No newline at end of file