signatures v1 and v2

client/mifare/ndef.c

@@ -160,14 +160,8 @@ static int ndefPrintHeader(NDEFHeader_t *header) {
     return PM3_SUCCESS;
 }
 
-static int ndefDecodeSig(uint8_t *sig, size_t siglen) {
+static int ndefDecodeSig1(uint8_t *sig, size_t siglen) {
-    size_t indx = 0;
+    size_t indx = 1;
-    PrintAndLogEx(NORMAL, "\tsignature version: 0x%02x", sig[0]);
-    if (sig[0] != 0x01 && sig[0] != 0x20) {
-        PrintAndLogEx(ERR, "signature version unknown.");
-        return PM3_ESOFT;
-    }
-    indx++;
 
     uint8_t sigType = sig[indx] & 0x7f;
     bool sigURI = sig[indx] & 0x80;
@@ -225,6 +219,85 @@ static int ndefDecodeSig(uint8_t *sig, size_t siglen) {
     return PM3_SUCCESS;
 };
 
+// https://github.com/nfcpy/ndeflib/blob/master/src/ndef/signature.py#L292
+static int ndefDecodeSig2(uint8_t *sig, size_t siglen) {
+    size_t indx = 1;
+
+    uint8_t sigType = sig[indx] & 0x7f;
+    bool sigURI = sig[indx] & 0x80;
+    indx++;
+    
+    uint8_t hashType = sig[indx];
+    indx++;
+
+    PrintAndLogEx(NORMAL, "\tsignature type: %s", ((sigType < stNA) ? ndefSigType_s[sigType] : ndefSigType_s[stNA]));
+    PrintAndLogEx(NORMAL, "\tsignature uri: %s", (sigURI ? "present" : "not present"));
+    PrintAndLogEx(NORMAL, "\thash type: %s", ((hashType == 0x02) ? "SHA-256" : "unknown");
+
+    if (sigURI) {
+        size_t intsigurilen = (sig[indx] << 8) + sig[indx + 1];
+        indx += 2;
+        PrintAndLogEx(NORMAL, "\tsignature uri [%zu]: %.*s", intsigurilen, (int)intsigurilen, &sig[indx]);
+        indx += intsigurilen;
+    }
+return 0;
+  /*  if (sigType == stECDSA_P192 || sigType == stECDSA_P256) {
+        indx += 3;
+        PrintAndLogEx(NORMAL, "\tsignature [%zu]: %s", intsiglen, sprint_hex_inrow(&sig[indx], intsiglen));
+
+        uint8_t rval[300] = {0};
+        uint8_t sval[300] = {0};
+        int res = ecdsa_asn1_get_signature(&sig[indx], intsiglen, rval, sval);
+        if (!res) {
+            PrintAndLogEx(NORMAL, "\t\tr: %s", sprint_hex(rval, 32));
+            PrintAndLogEx(NORMAL, "\t\ts: %s", sprint_hex(sval, 32));
+        }
+    }
+    indx += intsiglen;*/
+
+    uint8_t certFormat = (sig[indx] >> 4) & 0x07;
+    uint8_t certCount = sig[indx] & 0x0f;
+    bool certURI = sig[indx] & 0x80;
+
+    PrintAndLogEx(NORMAL, "\tcertificate format: %s", ((certFormat < sfNA) ? ndefCertificateFormat_s[certFormat] : ndefCertificateFormat_s[sfNA]));
+    PrintAndLogEx(NORMAL, "\tcertificates count: %d", certCount);
+
+    // print certificates
+    indx++;
+    for (int i = 0; i < certCount; i++) {
+        size_t intcertlen = (sig[indx + 1] << 8) + sig[indx + 2];
+        indx += 2;
+
+        PrintAndLogEx(NORMAL, "\tcertificate %d [%zu]: %s", i + 1, intcertlen, sprint_hex_inrow(&sig[indx], intcertlen));
+        indx += intcertlen;
+    }
+
+    // have certificate uri
+    if ((indx <= siglen) && certURI) {
+        size_t inturilen = (sig[indx] << 8) + sig[indx + 1];
+        indx += 2;
+        PrintAndLogEx(NORMAL, "\tcertificate uri [%zu]: %.*s", inturilen, (int)inturilen, &sig[indx]);
+    }
+
+    return PM3_SUCCESS;
+};
+
+static int ndefDecodeSig(uint8_t *sig, size_t siglen) {
+    PrintAndLogEx(NORMAL, "\tsignature version: 0x%02x", sig[0]);
+    if (sig[0] != 0x01 && sig[0] != 0x20) {
+        PrintAndLogEx(ERR, "signature version unknown.");
+        return PM3_ESOFT;
+    }
+    
+    if (sig[0] == 0x01)
+        return ndefDecodeSig1(sig, siglen);
+    
+    if (sig[0] == 0x20)
+        return ndefDecodeSig2(sig, siglen);
+    
+    return PM3_ESOFT;
+}
+
 static int ndefDecodePayload(NDEFHeader_t *ndef) {
 
     switch (ndef->TypeNameFormat) {