Add basic cloning support

client/src/cmdhfgallagher.c

@@ -11,6 +11,7 @@
  */
 
 #include "cmdhfgallagher.h"
+#include "generator.h"
 #include "mifare.h"
 #include "mifare/desfirecore.h"
 #include "mifare/gallaghercore.h"
@@ -48,6 +49,8 @@ static int readCardApplicationDirectory(DesfireContext_t *ctx, uint8_t *destBuf,
     for (uint8_t i = 0; i < 3; i++) {
         size_t readLen;
         DesfireReadFile(ctx, i, 0, 36, &destBuf[i * 36], &readLen);
+        // end if the last entry is NULL
+        if (memcmp(&destBuf[36 * i + 30], "\0\0\0\0\0\0", 6) == 0) break;
     }
 
     // Keep only valid entries
@@ -82,11 +85,11 @@ static int readCardApplicationCredentials(DesfireContext_t *ctx, uint8_t *aid, u
     DesfireSetCommandSet(ctx, DCCNativeISO);
 
     // Select and authenticate to AID
-    int res = DesfireSelectAndAuthenticateAppW(ctx, DACEV1, ISW6bAID, le24toh(aid), false, verbose);
+    int res = DesfireSelectAndAuthenticateAppW(ctx, DACEV1, ISW6bAID, DesfireAIDByteToUint(aid), false, verbose);
     HF_GALLAGHER_RETURN_IF_ERROR(res);
 
     // Read file 0 (contains credentials)
-    uint8_t buf[16] = { 0x00 };
+    uint8_t buf[16] = {0};
     size_t readLen = 0;
     DesfireSetCommMode(ctx, DCMEncrypted);
     res = DesfireReadFile(ctx, 0, 0, 16, buf, &readLen);
@@ -220,39 +223,362 @@ static int CmdGallagherReader(const char *Cmd) {
     return continuousMode ? PM3_SUCCESS : res;
 }
 
+int GallagherDiversifyKey(uint8_t *sitekey, uint8_t *uid, uint8_t uidLen, uint8_t keyNo, uint32_t aid, uint8_t *keyOut) {
+    // Generate diversification input
+    uint8_t kdfInputLen = 11;
+    int res = mfdes_kdf_input_gallagher(uid, uidLen, keyNo, aid, keyOut, &kdfInputLen);
+    HF_GALLAGHER_RETURN_IF_ERROR(res);
+
+    // Make temporary DesfireContext
+    DesfireContext_t dctx = {0};
+    DesfireSetKey(&dctx, 0, T_AES, sitekey);
+    
+    // Diversify input & copy to output buffer
+    MifareKdfAn10922(&dctx, DCOMasterKey, keyOut, kdfInputLen);
+    memcpy(keyOut, dctx.key, CRYPTO_AES128_KEY_SIZE);
+
+    return PM3_SUCCESS;
+}
+
+static int createGallagherCredentialsApplication(DesfireContext_t *ctx, uint8_t *sitekey, uint8_t *aid, bool verbose) {
+    DesfireSetCommMode(ctx, DCMPlain);
+    DesfireSetCommandSet(ctx, DCCNativeISO);
+    int res = DesfireSelectAndAuthenticateAppW(ctx, DACEV1, ISW6bAID, 0x000000, false, verbose);
+    HF_GALLAGHER_RETURN_IF_ERROR(res);
+
+    // Create application
+    DesfireCryptoAlgorithm dstalgo = T_AES;
+    uint8_t keycount = 3;
+    uint8_t ks1 = 0x0B;
+    uint8_t ks2 = (DesfireKeyAlgoToType(dstalgo) << 6) | keycount;;
+
+    uint8_t data[5] = {0};
+    memcpy(&data[0], aid, 3);
+    data[3] = ks1;
+    data[4] = ks2;
+
+    DesfireSetCommMode(ctx, DCMMACed);
+    res = DesfireCreateApplication(ctx, data, ARRAYLEN(data));
+    HF_GALLAGHER_RETURN_IF_ERROR(res);
+
+    // Select the new application
+    DesfireSetCommMode(ctx, DCMPlain);
+    res = DesfireSelectEx(ctx, true, ISW6bAID, DesfireAIDByteToUint(aid), NULL);
+    HF_GALLAGHER_RETURN_IF_ERROR(res);
+    if (verbose)
+        PrintAndLogEx(INFO, "AID: %06x is " _GREEN_("selected"), DesfireAIDByteToUint(aid));
+
+    // Add key 2, then key 0 (we must authenticate with key 0 in order to make changes)
+    for (int i = 2; i >= 0; i -= 2) {
+        // Diversify key
+        uint8_t buf[CRYPTO_AES128_KEY_SIZE] = {0};
+        res = GallagherDiversifyKey(sitekey, ctx->uid, ctx->uidlen, i, DesfireAIDByteToUint(aid), buf);
+        HF_GALLAGHER_RETURN_IF_ERROR(res);
+
+        if (verbose)
+            PrintAndLogEx(INFO, " Diversified key %d: " _GREEN_("%s"), i, sprint_hex_inrow(buf, ARRAYLEN(buf)));
+
+        // Authenticate
+        uint8_t blankKey[DESFIRE_MAX_KEY_SIZE] = {0};
+        DesfireSetKeyNoClear(ctx, 0, T_AES, blankKey);
+        DesfireSetCommMode(ctx, DCMPlain);
+        res = DesfireAuthenticate(ctx, DACEV1, verbose);
+        HF_GALLAGHER_RETURN_IF_ERROR(res);
+
+        // Change key
+        DesfireSetCommMode(ctx, DCMEncryptedPlain);
+        res = DesfireChangeKey(ctx, false, i, dstalgo, 1, buf, dstalgo, blankKey, true);
+        HF_GALLAGHER_RETURN_IF_ERROR(res);
+        if (verbose)
+            PrintAndLogEx(INFO, " Successfully set key %d", i);
+    }
+
+    return PM3_SUCCESS;
+}
+
+static int createGallagherCredentialsFile(DesfireContext_t *ctx, uint8_t *sitekey, uint8_t *aid, GallagherCredentials_t *creds, bool verbose) {
+    // Set up context
+    DesfireSetKeyNoClear(ctx, 0, T_AES, sitekey);
+    DesfireSetKdf(ctx, MFDES_KDF_ALGO_GALLAGHER, NULL, 0);
+    DesfireSetCommMode(ctx, DCMPlain);
+
+    // Select application
+    int res = DesfireSelectAndAuthenticateAppW(ctx, DACEV1, ISW6bAID, DesfireAIDByteToUint(aid), false, verbose);
+    HF_GALLAGHER_RETURN_IF_ERROR(res);
+
+    // Prepare create file command
+    uint8_t fileType = 0; // standard data file
+    uint8_t fileId = 0x00;
+    uint8_t fileSize = 16;
+    uint8_t fileAccessMode = 0x03; // encrypted
+    uint32_t fileRights = 0x2000; // key 0 has God mode, key 2 can read
+
+    uint8_t data[7] = {0};
+    data[0] = fileId;
+    data[1] = fileAccessMode;
+    data[2] = fileRights & 0xff;
+    data[3] = (fileRights >> 8) & 0xff;
+    Uint3byteToMemLe(&data[4], fileSize);
+
+    // Create file
+    res = DesfireCreateFile(ctx, fileType, data, ARRAYLEN(data), false);
+    HF_GALLAGHER_RETURN_IF_ERROR(res);
+
+    // Create file contents (2nd half is the bitwise inverse of the encoded creds)
+    uint8_t contents[16] = {0};
+    encodeCardholderCredentials(contents, creds);
+    for (int i = 0; i < 8; i++)
+        contents[i + 8] = contents[i] ^ 0xFF;
+
+    // Write file
+    DesfireSetCommMode(ctx, DCMEncrypted);
+    res = DesfireWriteFile(ctx, fileId, 0, ARRAYLEN(contents), contents);
+    HF_GALLAGHER_RETURN_IF_ERROR(res);
+
+    return PM3_SUCCESS;
+}
+
+static int createGallagherCAD(DesfireContext_t *ctx, uint8_t *sitekey, bool verbose) {
+    DesfireClearSession(ctx);
+    DesfireSetCommMode(ctx, DCMPlain);
+    DesfireSetCommandSet(ctx, DCCNativeISO);
+    int res = DesfireSelectAndAuthenticateAppW(ctx, DACEV1, ISW6bAID, 0x000000, false, verbose);
+    HF_GALLAGHER_RETURN_IF_ERROR(res);
+
+    // Create application
+    uint32_t aid = 0x2F81F4;
+    DesfireCryptoAlgorithm dstalgo = T_AES;
+    uint8_t keycount = 1;
+    uint8_t ks1 = 0x0B;
+    uint8_t ks2 = (DesfireKeyAlgoToType(dstalgo) << 6) | keycount;;
+
+    uint8_t data[5] = {0};
+    DesfireAIDUintToByte(aid, &data[0]);
+    data[3] = ks1;
+    data[4] = ks2;
+
+    DesfireSetCommMode(ctx, DCMMACed);
+    res = DesfireCreateApplication(ctx, data, ARRAYLEN(data));
+    HF_GALLAGHER_RETURN_IF_ERROR(res);
+
+    // Select the new application
+    DesfireSetCommMode(ctx, DCMPlain);
+    res = DesfireSelectEx(ctx, true, ISW6bAID, aid, NULL);
+    HF_GALLAGHER_RETURN_IF_ERROR(res);
+    if (verbose)
+        PrintAndLogEx(INFO, "AID: %06x is " _GREEN_("selected"), aid);
+
+    // Diversify key
+    uint8_t buf[CRYPTO_AES128_KEY_SIZE] = {0};
+    res = GallagherDiversifyKey(sitekey, ctx->uid, ctx->uidlen, 0, aid, buf);
+    HF_GALLAGHER_RETURN_IF_ERROR(res);
+
+    if (verbose)
+        PrintAndLogEx(INFO, " Diversified key 0: " _GREEN_("%s"), sprint_hex_inrow(buf, ARRAYLEN(buf)));
+
+    // Authenticate
+    uint8_t blankKey[DESFIRE_MAX_KEY_SIZE] = {0};
+    DesfireSetKeyNoClear(ctx, 0, T_AES, blankKey);
+    DesfireSetCommMode(ctx, DCMPlain);
+    res = DesfireAuthenticate(ctx, DACEV1, verbose);
+    HF_GALLAGHER_RETURN_IF_ERROR(res);
+
+    // Change key
+    DesfireSetCommMode(ctx, DCMEncryptedPlain);
+    res = DesfireChangeKey(ctx, false, 0, dstalgo, 1, buf, dstalgo, blankKey, true);
+    HF_GALLAGHER_RETURN_IF_ERROR(res);
+    if (verbose)
+        PrintAndLogEx(INFO, " Successfully set key 0");
+
+    return PM3_SUCCESS;
+}
+
+static int updateGallagherCAD(DesfireContext_t *ctx, uint8_t *sitekey, uint8_t *aid, GallagherCredentials_t *creds, bool verbose) {
+    uint32_t cadAid = 0x2F81F4;
+
+
+    // Check if CAD exists
+    uint8_t cad[36 * 3] = {0};
+    uint8_t numEntries = 0;
+    int res = DesfireSelectEx(ctx, true, ISW6bAID, cadAid, NULL);
+    if (res == PM3_SUCCESS) {
+        res = readCardApplicationDirectory(ctx, cad, ARRAYLEN(cad), &numEntries, verbose);
+        HF_GALLAGHER_RETURN_IF_ERROR(res);
+    } else {
+        DesfireSetCommandSet(ctx, DCCNativeISO);
+        res = createGallagherCAD(ctx, sitekey, verbose);
+        HF_GALLAGHER_RETURN_IF_ERROR(res);
+
+        // Check that there is space for the new entry
+        if (numEntries == 18) {
+            PrintAndLogEx(ERR, "Card application directory is full.");
+            return PM3_EFATAL;
+        }
+    }
+
+    uint8_t fileId = numEntries / 6; // 6 entries per file
+    uint8_t entryNum = numEntries % 6;
+
+    // Create entry
+    uint8_t *entry = &cad[numEntries * 6];
+    entry[0] = creds->region_code;
+    entry[1] = (creds->facility_code >> 8) & 0xFF;
+    entry[2] = creds->facility_code & 0xFF;
+    memcpy(&entry[3], aid, 3);
+    reverseAid(&entry[3]); // CAD stores AIDs backwards
+
+    // Set up context
+    DesfireSetKeyNoClear(ctx, 0, T_AES, sitekey);
+    DesfireSetKdf(ctx, MFDES_KDF_ALGO_GALLAGHER, NULL, 0);
+    DesfireSetCommMode(ctx, DCMPlain);
+
+    // Select application
+    res = DesfireSelectAndAuthenticateAppW(ctx, DACEV1, ISW6bAID, cadAid, false, verbose);
+    HF_GALLAGHER_RETURN_IF_ERROR(res);
+
+    // Create file if necessary
+    if (entryNum == 0) {
+        // Prepare create file command
+        uint8_t fileType = 0; // standard data file
+        uint8_t fileSize = 36;
+        uint8_t fileAccessMode = 0x00; // plain
+        uint32_t fileRights = 0xE000; // key 0 has God mode, everyone can read
+
+        uint8_t data[7] = {0};
+        data[0] = fileId;
+        data[1] = fileAccessMode;
+        data[2] = fileRights & 0xff;
+        data[3] = (fileRights >> 8) & 0xff;
+        Uint3byteToMemLe(&data[4], fileSize);
+
+        // Create file
+        res = DesfireCreateFile(ctx, fileType, data, ARRAYLEN(data), false);
+        HF_GALLAGHER_RETURN_IF_ERROR(res);
+
+        // Write file
+        res = DesfireWriteFile(ctx, fileId, fileId * 36, 36, entry);
+        HF_GALLAGHER_RETURN_IF_ERROR(res);
+    } else {
+        // Write file
+        res = DesfireWriteFile(ctx, fileId, entryNum * 6, 6, entry);
+        HF_GALLAGHER_RETURN_IF_ERROR(res);
+    }
+
+    return PM3_SUCCESS;
+}
+
 static int CmdGallagherClone(const char *Cmd) {
     CLIParserContext *ctx;
     CLIParserInit(&ctx, "hf gallagher clone",
                     "clone a GALLAGHER card to a blank DESFire card.",
-                    "hf gallagher clone --rc 1 --fc 22 --cn 3333 --il 4"
+                    "hf gallagher clone --rc 1 --fc 22 --cn 3333 --il 4 --sitekey 00112233445566778899aabbccddeeff"
                 );
 
     void *argtable[] = {
         arg_param_begin,
+        arg_lit0(NULL, "apdu",                  "show APDU requests and responses"),
+        arg_lit0("v",  "verbose",               "Verbose mode"),
+        arg_int0("n",  "keyno",   "<decimal>",  "Key number [default=0]"),
+        arg_str0("t",  "algo",    "<DES/2TDEA/3TDEA/AES>", "Crypt algo: DES, 2TDEA, 3TDEA, AES"),
+        arg_str0("k",  "key",     "<hex>",      "Key for authenticate (HEX 8(DES), 16(2TDEA or AES) or 24(3TDEA) bytes)"),
+
         arg_u64_1(NULL, "rc",      "<decimal>", "Region code. 4 bits max"),
         arg_u64_1(NULL, "fc",      "<decimal>", "Facility code. 2 bytes max"),
         arg_u64_1(NULL, "cn",      "<decimal>", "Card number. 3 bytes max"),
         arg_u64_1(NULL, "il",      "<decimal>", "Issue level. 4 bits max"),
+        arg_str0(NULL,  "aid",     "<hex>",     "Application ID to write (3 bytes) [default=2081F4]"),
+        arg_str1(NULL,  "sitekey", "<hex>",     "Master site key to compute diversified keys (16 bytes)"),
         arg_param_end
     };
     CLIExecWithReturn(ctx, Cmd, argtable, false);
 
-    uint64_t region_code = arg_get_u64(ctx, 1); // uint16, will be validated later
+    SetAPDULogging(arg_get_lit(ctx, 1));
-    uint64_t facility_code = arg_get_u64(ctx, 2); // uint32, will be validated later
+    bool verbose = arg_get_lit(ctx, 2) || true;
-    uint64_t card_number = arg_get_u64(ctx, 3); // uint64
+    int keyNum = arg_get_int_def(ctx, 3, 0);
-    uint64_t issue_level = arg_get_u64(ctx, 4); // uint32, will be validated later
+    
+    int algo = T_DES;
+    if (CLIGetOptionList(arg_get_str(ctx, 4), DesfireAlgoOpts, &algo)) return PM3_ESOFT;
+
+    int keyLen = 0;
+    uint8_t key[DESFIRE_MAX_KEY_SIZE] = {0};
+    CLIGetHexWithReturn(ctx, 5, key, &keyLen);
+    if (keyLen && keyLen != desfire_get_key_length(algo)) {
+        PrintAndLogEx(ERR, "%s key must have %d bytes length instead of %d.", CLIGetOptionListStr(DesfireAlgoOpts, algo), desfire_get_key_length(algo), keyLen);
+        return PM3_EINVARG;
+    }
+    if (keyLen == 0) {
+        // Default to a key of all zeros
+        keyLen = desfire_get_key_length(algo);
+    }
+
+    uint64_t region_code = arg_get_u64(ctx, 6); // uint16, will be validated later
+    uint64_t facility_code = arg_get_u64(ctx, 7); // uint32, will be validated later
+    uint64_t card_number = arg_get_u64(ctx, 8); // uint64
+    uint64_t issue_level = arg_get_u64(ctx, 9); // uint32, will be validated later
+
+    int aidLen = 0;
+    uint8_t aid[3] = "\x20\x81\xF4";
+    CLIGetHexWithReturn(ctx, 10, aid, &aidLen);
+    if (aidLen > 0 && aidLen != 3) {
+        PrintAndLogEx(ERR, "--aid must be 3 bytes");
+        return PM3_EINVARG;
+    }
+    reverseAid(aid); // PM3 displays AIDs backwards
+
+    // Check that the AID is in the expected range
+    if (memcmp(aid, "\xF4\x81", 2) != 0 || aid[2] < 0x20 || aid[2] > 0x2B) {
+        PrintAndLogEx(WARNING, "Invalid Gallagher AID %06X, expected 2?81F4.", DesfireAIDByteToUint(aid));
+    }
+    
+    int sitekeyLen = 0;
+    uint8_t sitekey[16] = {0};
+    CLIGetHexWithReturn(ctx, 11, sitekey, &sitekeyLen);
+    if (sitekeyLen > 0 && sitekeyLen != 16) {
+        PrintAndLogEx(ERR, "--sitekey must be 16 bytes");
+        return PM3_EINVARG;
+    }
     CLIParserFree(ctx);
 
     if (!isValidGallagherCredentials(region_code, facility_code, card_number, issue_level)) {
         return PM3_EINVARG;
     }
+    GallagherCredentials_t creds = {
+        .region_code = region_code,
+        .facility_code = facility_code,
+        .card_number = card_number,
+        .issue_level = issue_level,
+    };
 
-    // TODO: create data
+    // Set up context
+    DropField();
+    DesfireContext_t dctx = {0};
+    DesfireClearContext(&dctx);
 
-    PrintAndLogEx(INFO, "Preparing to clone Gallagher from specified data.");
+    // Get card UID (for key diversification)
+    int res = DesfireGetCardUID(&dctx);
+    HF_GALLAGHER_FAIL_IF_ERROR(res, true, "Failed retrieving card UID.");
 
-    // TODO: write data
+    // Create application
+        DesfireSetKeyNoClear(&dctx, keyNum, algo, key);
+        DesfireSetKdf(&dctx, MFDES_KDF_ALGO_NONE, NULL, 0);
+        res = createGallagherCredentialsApplication(&dctx, sitekey, aid, verbose);
+        HF_GALLAGHER_FAIL_IF_ERROR(res, true, "Failed creating Gallagher application.");
+        DropField();
 
+    // Create credential files
+        // Don't need to set keys here, they're generated automatically
+        res = createGallagherCredentialsFile(&dctx, sitekey, aid, &creds, verbose);
+        HF_GALLAGHER_FAIL_IF_ERROR(res, true, "Failed creating Gallagher credential file.");
+        DropField();
+
+    // Update card application directory
+        DesfireSetKeyNoClear(&dctx, keyNum, algo, key);
+        DesfireSetKdf(&dctx, MFDES_KDF_ALGO_NONE, NULL, 0);
+        res = updateGallagherCAD(&dctx, sitekey, aid, &creds, verbose);
+        HF_GALLAGHER_FAIL_IF_ERROR(res, true, "Failed updating Gallagher card application directory.");
+        DropField();
+
+    DropField();
     PrintAndLogEx(SUCCESS, "Done");
     PrintAndLogEx(HINT, "Hint: try " _YELLOW_("`hf gallagher reader`") " to verify");
     return PM3_ENOTIMPL;

client/src/cmdhfgallagher.h

@@ -13,9 +13,24 @@
 #define CMDHFGALLAGHER_H__
 
 #include "common.h"
+#include <stdint.h>
 
 int CmdHFGallagher(const char *Cmd);
 
+/**
+ * @brief Create Gallagher Application Master Key by diversifying
+ * the MIFARE Site Key with card UID, key number, and application ID.
+ * 
+ * @param sitekey MIFARE Site Key (16 bytes).
+ * @param uid Card unique ID (4 or 7 bytes).
+ * @param uidLen Length of UID.
+ * @param keyNum Key number (0 <= keyNum <= 2).
+ * @param aid Application ID (0x2?81F4 where 0 <= ? <= B).
+ * @param keyOut Buffer to copy the diversified key into (must be 16 bytes).
+ * @return PM3_SUCCESS if successful, PM3_EINVARG if an argument is invalid.
+ */
+int GallagherDiversifyKey(uint8_t *sitekey, uint8_t *uid, uint8_t uidLen, uint8_t keyNum, uint32_t aid, uint8_t *keyOut);
+
 #define HF_GALLAGHER_RETURN_IF_ERROR(res) if (res != PM3_SUCCESS) { return res; }
 #define HF_GALLAGHER_FAIL_IF_ERROR(res, verbose, reason) if (res != PM3_SUCCESS) { if (verbose) PrintAndLogEx(ERR, reason " Error code %d", res); DropField(); return res; }