Fix PDOL parsing

DarkFlippers · Feb 9, 2024 · d195de5 · d195de5
1 parent ec35662
commit d195de5
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Showing 2 changed files with 19 additions and 23 deletions.
diff --git a/applications/main/nfc/helpers/protocol_support/emv/emv_render.c b/applications/main/nfc/helpers/protocol_support/emv/emv_render.c
@@ -29,18 +29,6 @@ void nfc_render_emv_uid(const uint8_t* uid, const uint8_t uid_len, FuriString* s
     furi_string_cat_printf(str, "\n");
 }
 
-void nfc_render_emv_aid(const uint8_t* uid, const uint8_t uid_len, FuriString* str) {
-    if(uid_len == 0) return;
-
-    furi_string_cat_printf(str, "UID: ");
-
-    for(uint8_t i = 0; i < uid_len; i++) {
-        furi_string_cat_printf(str, "%02X ", uid[i]);
-    }
-
-    furi_string_cat_printf(str, "\n");
-}
-
 void nfc_render_emv_data(const EmvData* data, FuriString* str) {
     nfc_render_emv_pan(data->emv_application.pan, data->emv_application.pan_len, str);
     nfc_render_emv_name(data->emv_application.name, str);
@@ -83,7 +71,7 @@ void nfc_render_emv_application(const EmvApplication* apl, FuriString* str) {
         return;
     }
 
-    furi_string_cat_printf(str, "  AID:");
+    furi_string_cat_printf(str, "AID: ");
     for(uint8_t i = 0; i < len; i++) furi_string_cat_printf(str, "%02X", apl->aid[i]);
     furi_string_cat_printf(str, "\n");
 }

diff --git a/lib/nfc/protocols/emv/emv_poller_i.c b/lib/nfc/protocols/emv/emv_poller_i.c
@@ -3,6 +3,7 @@
 
 #define TAG "EMVPoller"
 
+// "Terminal" parameters, which could be requested by card
 const PDOLValue pdol_term_info = {0x9F59, {0xC8, 0x80, 0x00}}; // Terminal transaction information
 const PDOLValue pdol_term_type = {0x9F5A, {0x00}}; // Terminal transaction type
 const PDOLValue pdol_merchant_type = {0x9F58, {0x01}}; // Merchant type indicator
@@ -392,18 +393,25 @@ static void emv_prepare_pdol(APDU* dest, APDU* src) {
     uint8_t tlen = 0;
     uint8_t i = 0;
     while(i < src->size) {
-        bool tag_found = emv_parse_tag(src->data, src->size, &tag, &tlen, &i);
-        if(tag_found) {
-            for(uint8_t j = 0; j < COUNT_OF(pdol_values); j++) {
-                if(tag == pdol_values[j]->tag) {
-                    memcpy(dest->data + dest->size, pdol_values[j]->data, tlen);
-                    dest->size += tlen;
-                    break;
-                }
+        bool tag_found = false;
+        if(!emv_parse_tag(src->data, src->size, &tag, &tlen, &i)) {
+            FURI_LOG_T(TAG, "Parsing PDOL failed at 0x%x", i);
+            dest->size = 0;
+            return;
+        }
+
+        furi_check(dest->size + tlen < sizeof(dest->data));
+        for(uint8_t j = 0; j < COUNT_OF(pdol_values); j++) {
+            if(tag == pdol_values[j]->tag) {
+                memcpy(dest->data + dest->size, pdol_values[j]->data, tlen);
+                dest->size += tlen;
+                tag_found = true;
+                break;
             }
-        } else {
+        }
+
+        if(!tag_found) {
             // Unknown tag, fill zeros
-            furi_check(dest->size + tlen < sizeof(dest->data));
             memset(dest->data + dest->size, 0, tlen);
             dest->size += tlen;
         }