Move cmd functions to separate files.

Signed-off-by: Pol Henarejos <pol.henarejos@cttc.es>

src/openpgp/cmd_change_pin.c

@@ -0,0 +1,62 @@
+/*
+ * This file is part of the Pico OpenPGP distribution (https://github.com/polhenarejos/pico-openpgp).
+ * Copyright (c) 2022 Pol Henarejos.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 3.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "openpgp.h"
+
+int cmd_change_pin() {
+    if (P1(apdu) != 0x0) {
+        return SW_WRONG_P1P2();
+    }
+    uint16_t fid = 0x1000 | P2(apdu);
+    file_t *pw;
+    if (!(pw = search_by_fid(fid, NULL, SPECIFY_EF))) {
+        return SW_REFERENCE_NOT_FOUND();
+    }
+    uint8_t pin_len = file_get_data(pw)[0];
+    uint16_t r = 0;
+    if ((r = load_dek()) != PICOKEY_OK) {
+        return SW_EXEC_ERROR();
+    }
+    r = check_pin(pw, apdu.data, pin_len);
+    if (r != 0x9000) {
+        return r;
+    }
+    uint8_t dhash[33];
+    dhash[0] = apdu.nc - pin_len;
+    double_hash_pin(apdu.data + pin_len, apdu.nc - pin_len, dhash + 1);
+    file_put_data(pw, dhash, sizeof(dhash));
+
+    file_t *tf = search_by_fid(EF_DEK, NULL, SPECIFY_EF);
+    if (!tf) {
+        return SW_REFERENCE_NOT_FOUND();
+    }
+    uint8_t def[IV_SIZE + 32 + 32 + 32 + 32] = {0};
+    memcpy(def, file_get_data(tf), file_get_size(tf));
+    if (P2(apdu) == 0x81) {
+        hash_multi(apdu.data + pin_len, apdu.nc - pin_len, session_pw1);
+        memcpy(def + IV_SIZE, dek + IV_SIZE, 32);
+        aes_encrypt_cfb_256(session_pw1, def, def + IV_SIZE, 32);
+    }
+    else if (P2(apdu) == 0x83) {
+        hash_multi(apdu.data + pin_len, apdu.nc - pin_len, session_pw3);
+        memcpy(def + IV_SIZE + 32 + 32, dek + IV_SIZE, 32);
+        aes_encrypt_cfb_256(session_pw3, def, def + IV_SIZE + 32 + 32, 32);
+    }
+    file_put_data(tf, def, sizeof(def));
+    low_flash_available();
+    return SW_OK();
+}