Extracted TDES auth to separate method

lib/nfc/protocols/mf_ultralight/mf_ultralight_poller.c

@@ -453,29 +453,11 @@ static NfcCommand mf_ultralight_poller_handler_auth_ultralight_c(MfUltralightPol
         if(!instance->mfu_event.data->auth_context.skip_auth) {
             FURI_LOG_D(TAG, "Trying to authenticate with 3des key");
             instance->auth_context.tdes_key = instance->mfu_event.data->auth_context.tdes_key;
-            do {
-                uint8_t output[MF_ULTRALIGHT_C_AUTH_DATA_SIZE];
-                uint8_t RndA[MF_ULTRALIGHT_C_AUTH_RND_BLOCK_SIZE] = {0};
-                furi_hal_random_fill_buf(RndA, sizeof(RndA));
-                instance->error = mf_ultralight_poller_authenticate_start(instance, RndA, output);
-                if(instance->error != MfUltralightErrorNone) break;
+            instance->error = mf_ultralight_poller_auth_tdes(instance, &instance->auth_context);
 
-                uint8_t decoded_shifted_RndA[MF_ULTRALIGHT_C_AUTH_RND_BLOCK_SIZE] = {0};
-                const uint8_t* RndB = output + MF_ULTRALIGHT_C_AUTH_RND_B_BLOCK_OFFSET;
-                instance->error = mf_ultralight_poller_authenticate_end(
-                    instance, RndB, output, decoded_shifted_RndA);
-                if(instance->error != MfUltralightErrorNone) break;
-
-                mf_ultralight_3des_shift_data(RndA);
-                instance->auth_context.auth_success =
-                    (memcmp(RndA, decoded_shifted_RndA, sizeof(decoded_shifted_RndA)) == 0);
-
-                if(instance->auth_context.auth_success) {
-                    FURI_LOG_D(TAG, "Auth success");
-                }
-            } while(false);
-
-            if(instance->error != MfUltralightErrorNone || !instance->auth_context.auth_success) {
+            if(instance->error == MfUltralightErrorNone && instance->auth_context.auth_success) {
+                FURI_LOG_D(TAG, "Auth success");
+            } else {
                 FURI_LOG_D(TAG, "Auth failed");
                 iso14443_3a_poller_halt(instance->iso14443_3a_poller);
             }

lib/nfc/protocols/mf_ultralight/mf_ultralight_poller.h

@@ -81,6 +81,19 @@ MfUltralightError mf_ultralight_poller_auth_pwd(
     MfUltralightPoller* instance,
     MfUltralightPollerAuthContext* data);
 
+/**
+ * @brief Perform 3DES authentication with key.
+ *
+ * Must ONLY be used inside the callback function.
+ *
+ * @param[in, out] instance pointer to the instance to be used in the transaction.
+ * @param[in, out] data pointer to the authentication context.
+ * @return MfUltralightErrorNone on success, an error code on failure.
+ */
+MfUltralightError mf_ultralight_poller_auth_tdes(
+    MfUltralightPoller* instance,
+    MfUltralightPollerAuthContext* data);
+
 /**
  * @brief Start authentication procedure.
  *

lib/nfc/protocols/mf_ultralight/mf_ultralight_poller_i.c

@@ -1,6 +1,7 @@
 #include "mf_ultralight_poller_i.h"
 
 #include <furi.h>
+#include <furi_hal.h>
 
 #define TAG "MfUltralightPoller"
 
@@ -62,6 +63,38 @@ MfUltralightError mf_ultralight_poller_auth_pwd(
     return ret;
 }
 
+MfUltralightError mf_ultralight_poller_auth_tdes(
+    MfUltralightPoller* instance,
+    MfUltralightPollerAuthContext* data) {
+    furi_check(instance);
+    furi_check(data);
+
+    MfUltralightError ret = MfUltralightErrorNone;
+
+    uint8_t output[MF_ULTRALIGHT_C_AUTH_DATA_SIZE];
+    uint8_t RndA[MF_ULTRALIGHT_C_AUTH_RND_BLOCK_SIZE] = {0};
+    furi_hal_random_fill_buf(RndA, sizeof(RndA));
+
+    ret = mf_ultralight_poller_authenticate_start(instance, RndA, output);
+
+    if(ret != MfUltralightErrorNone) {
+        return ret;
+    }
+
+    uint8_t decoded_shifted_RndA[MF_ULTRALIGHT_C_AUTH_RND_BLOCK_SIZE] = {0};
+    const uint8_t* RndB = output + MF_ULTRALIGHT_C_AUTH_RND_B_BLOCK_OFFSET;
+    ret = mf_ultralight_poller_authenticate_end(instance, RndB, output, decoded_shifted_RndA);
+
+    if(ret != MfUltralightErrorNone) {
+        return ret;
+    }
+
+    mf_ultralight_3des_shift_data(RndA);
+    data->auth_success = (memcmp(RndA, decoded_shifted_RndA, sizeof(decoded_shifted_RndA)) == 0);
+
+    return ret;
+}
+
 static MfUltralightError mf_ultralight_poller_send_authenticate_cmd(
     MfUltralightPoller* instance,
     const uint8_t* cmd,

targets/f7/api_symbols.csv

@@ -1,5 +1,5 @@
 entry,status,name,type,params
-Version,+,86.0,,
+Version,+,86.2,,
 Header,+,applications/drivers/subghz/cc1101_ext/cc1101_ext_interconnect.h,,
 Header,+,applications/services/bt/bt_service/bt.h,,
 Header,+,applications/services/bt/bt_service/bt_keys_storage.h,,
@@ -2741,6 +2741,7 @@ Function,+,mf_ultralight_is_equal,_Bool,"const MfUltralightData*, const MfUltral
 Function,+,mf_ultralight_is_page_pwd_or_pack,_Bool,"MfUltralightType, uint16_t"
 Function,+,mf_ultralight_load,_Bool,"MfUltralightData*, FlipperFormat*, uint32_t"
 Function,+,mf_ultralight_poller_auth_pwd,MfUltralightError,"MfUltralightPoller*, MfUltralightPollerAuthContext*"
+Function,+,mf_ultralight_poller_auth_tdes,MfUltralightError,"MfUltralightPoller*, MfUltralightPollerAuthContext*"
 Function,+,mf_ultralight_poller_authenticate_end,MfUltralightError,"MfUltralightPoller*, const uint8_t*, const uint8_t*, uint8_t*"
 Function,+,mf_ultralight_poller_authenticate_start,MfUltralightError,"MfUltralightPoller*, const uint8_t*, uint8_t*"
 Function,+,mf_ultralight_poller_read_counter,MfUltralightError,"MfUltralightPoller*, uint8_t, MfUltralightCounter*"