LRPEncode ok

client/src/mifare/desfiretest.c

@@ -617,6 +617,32 @@ static bool TestLRPIncCounter(void) {
     return res;
 }
 
+static bool TestLRPEncode(void) {
+    bool res = true;
+    
+    uint8_t resp[100] = {0}; 
+    size_t resplen = 0;
+
+    LRPContext ctx = {0};
+
+    uint8_t key1[] = {0xE0, 0xC4, 0x93, 0x5F, 0xF0, 0xC2, 0x54, 0xCD, 0x2C, 0xEF, 0x8F, 0xDD, 0xC3, 0x24, 0x60, 0xCF};
+    uint8_t iv1[] = {0xC3, 0x31, 0x5D, 0xBF};
+    LRPSetKeyEx(&ctx, key1, iv1, sizeof(iv1) * 2, 0, true);
+    uint8_t data1[] = {0x01, 0x2D, 0x7F, 0x16, 0x53, 0xCA, 0xF6, 0x50, 0x3C, 0x6A, 0xB0, 0xC1, 0x01, 0x0E, 0x8C, 0xB0};
+    LRPEncode(&ctx, data1, sizeof (data1), resp, &resplen);
+    uint8_t res1[] = {0xFC, 0xBB, 0xAC, 0xAA, 0x4F, 0x29, 0x18, 0x24, 0x64, 0xF9, 0x9D, 0xE4, 0x10, 0x85, 0x26, 0x6F, 
+                      0x48, 0x0E, 0x86, 0x3E, 0x48, 0x7B, 0xAA, 0xF6, 0x87, 0xB4, 0x3E, 0xD1, 0xEC, 0xE0, 0xD6, 0x23};
+    res = res && (resplen == sizeof(res1));
+    res = res && (memcmp(resp, res1, sizeof(res1)) == 0);
+
+    if (res)
+        PrintAndLogEx(INFO, "LRP encode........ " _GREEN_("passed"));
+    else
+        PrintAndLogEx(ERR,  "LRP encode........ " _RED_("fail"));
+
+    return res;
+}
+
 bool DesfireTest(bool verbose) {
     bool res = true;
 
@@ -639,6 +665,7 @@ bool DesfireTest(bool verbose) {
     res = res && TestLRPUpdatedKeys();
     res = res && TestLRPEval();
     res = res && TestLRPIncCounter();
+    res = res && TestLRPEncode();
 
     PrintAndLogEx(INFO, "---------------------------");
     if (res)

client/src/mifare/lrpcrypto.c

@@ -53,6 +53,17 @@ void LRPSetKey(LRPContext *ctx, uint8_t *key, size_t updatedKeyNum, bool useBitP
     ctx->useBitPadding = useBitPadding;
 }
 
+void LRPSetCounter(LRPContext *ctx, uint8_t *counter, size_t counterLenNibbles) {
+    memcpy(ctx->counter, counter, counterLenNibbles / 2);
+    ctx->counterLenNibbles = counterLenNibbles;
+}
+
+void LRPSetKeyEx(LRPContext *ctx, uint8_t *key, uint8_t *counter, size_t counterLenNibbles, size_t updatedKeyNum, bool useBitPadding){
+    LRPSetKey(ctx, key, updatedKeyNum, useBitPadding);
+    LRPSetCounter(ctx, counter, counterLenNibbles);
+}
+
+
 // https://www.nxp.com/docs/en/application-note/AN12304.pdf
 // Algorithm 1
 void LRPGeneratePlaintexts(LRPContext *ctx, size_t plaintextsCount) {
@@ -120,3 +131,29 @@ void LRPIncCounter(uint8_t *ctr, size_t ctrlen) {
     }
 }
 
+// https://www.nxp.com/docs/en/application-note/AN12304.pdf
+// Algorithm 4
+void LRPEncode(LRPContext *ctx, uint8_t *data, size_t datalen, uint8_t *resp, size_t *resplen) {
+    *resplen = 0;
+    
+    uint8_t xdata[1024] = {0};
+    memcpy(xdata, data, datalen);
+    if (ctx->useBitPadding) {
+        xdata[datalen] = 0x80;
+        datalen++;
+    }
+    
+    if (datalen % CRYPTO_AES128_KEY_SIZE)
+        datalen = datalen + CRYPTO_AES128_KEY_SIZE - (datalen % CRYPTO_AES128_KEY_SIZE);
+    
+    if (datalen == 0)
+        return;
+
+    uint8_t y[CRYPTO_AES128_KEY_SIZE] = {0};
+    for (int i = 0; i < datalen / CRYPTO_AES128_KEY_SIZE; i++) {
+        LRPEvalLRP(ctx, ctx->counter, ctx->counterLenNibbles, true, y);
+        aes_encode(NULL, y, &xdata[i * CRYPTO_AES128_KEY_SIZE], &resp[i * CRYPTO_AES128_KEY_SIZE], CRYPTO_AES128_KEY_SIZE);
+        *resplen += CRYPTO_AES128_KEY_SIZE;
+        LRPIncCounter(ctx->counter, ctx->counterLenNibbles);
+    }
+}

client/src/mifare/lrpcrypto.h

@@ -25,6 +25,7 @@
 
 #define LRP_MAX_PLAINTEXTS_SIZE 16
 #define LRP_MAX_UPDATED_KEYS_SIZE 4
+#define LRP_MAX_COUNTER_SIZE (CRYPTO_AES128_KEY_SIZE * 4)
 
 typedef struct {
     uint8_t key[CRYPTO_AES128_KEY_SIZE];
@@ -35,14 +36,19 @@ typedef struct {
     size_t updatedKeysCount;
     uint8_t updatedKeys[LRP_MAX_UPDATED_KEYS_SIZE][CRYPTO_AES128_KEY_SIZE];
     size_t useUpdatedKeyNum;
+    
+    uint8_t counter[LRP_MAX_COUNTER_SIZE];
+    size_t counterLenNibbles; // len in bytes * 2 (or * 2 - 1)
 } LRPContext;
 
 void LRPClearContext(LRPContext *ctx);
 void LRPSetKey(LRPContext *ctx, uint8_t *key, size_t updatedKeyNum, bool useBitPadding);
+void LRPSetKeyEx(LRPContext *ctx, uint8_t *key, uint8_t *counter, size_t counterLenNibbles, size_t updatedKeyNum, bool useBitPadding);
+void LRPSetCounter(LRPContext *ctx, uint8_t *counter, size_t counterLenNibbles);
 void LRPGeneratePlaintexts(LRPContext *ctx, size_t plaintextsCount);
 void LRPGenerateUpdatedKeys(LRPContext *ctx, size_t updatedKeysCount);
 void LRPEvalLRP(LRPContext *ctx, uint8_t *iv, size_t ivlen, bool final, uint8_t *y);
 void LRPIncCounter(uint8_t *ctr, size_t ctrlen);
-void LRPEncode(LRPContext *ctx, uint8_t *ctr, size_t ctrlen, uint8_t *resp, size_t *resplen);
+void LRPEncode(LRPContext *ctx, uint8_t *data, size_t datalen, uint8_t *resp, size_t *resplen);
 
 #endif // __LRPCRYPTO_H