Move cmd functions to separate files.

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

src/openpgp/cmd_keypair_gen.c

@@ -0,0 +1,138 @@
+/*
+ * 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"
+#include "do.h"
+#include "random.h"
+
+int cmd_keypair_gen() {
+    if (P2(apdu) != 0x0) {
+        return SW_INCORRECT_P1P2();
+    }
+    if (apdu.nc != 2 && apdu.nc != 5) {
+        return SW_WRONG_LENGTH();
+    }
+    if (!has_pw3 && P1(apdu) == 0x80) {
+        return SW_SECURITY_STATUS_NOT_SATISFIED();
+    }
+
+    uint16_t fid = 0x0;
+    int r = PICOKEY_OK;
+    if (apdu.data[0] == 0xB6) {
+        fid = EF_PK_SIG;
+    }
+    else if (apdu.data[0] == 0xB8) {
+        fid = EF_PK_DEC;
+    }
+    else if (apdu.data[0] == 0xA4) {
+        fid = EF_PK_AUT;
+    }
+    else {
+        return SW_WRONG_DATA();
+    }
+
+    file_t *algo_ef = search_by_fid(fid - 0x0010, NULL, SPECIFY_EF);
+    if (!algo_ef) {
+        return SW_REFERENCE_NOT_FOUND();
+    }
+    const uint8_t *algo = algorithm_attr_rsa2k + 1;
+    uint16_t algo_len = algorithm_attr_rsa2k[0];
+    if (algo_ef && algo_ef->data) {
+        algo = file_get_data(algo_ef);
+        algo_len = file_get_size(algo_ef);
+    }
+    if (P1(apdu) == 0x80) { //generate
+        if (algo[0] == ALGO_RSA) {
+            int exponent = 65537, nlen = (algo[1] << 8) | algo[2];
+            printf("KEYPAIR RSA %d\r\n", nlen);
+            //if (nlen != 2048 && nlen != 4096)
+            //    return SW_FUNC_NOT_SUPPORTED();
+            mbedtls_rsa_context rsa;
+            mbedtls_rsa_init(&rsa);
+            uint8_t index = 0;
+            r = mbedtls_rsa_gen_key(&rsa, random_gen, &index, nlen, exponent);
+            if (r != 0) {
+                mbedtls_rsa_free(&rsa);
+                return SW_EXEC_ERROR();
+            }
+            r = store_keys(&rsa, ALGO_RSA, fid, true);
+            make_rsa_response(&rsa);
+            mbedtls_rsa_free(&rsa);
+            if (r != PICOKEY_OK) {
+                return SW_EXEC_ERROR();
+            }
+        }
+        else if (algo[0] == ALGO_ECDH || algo[0] == ALGO_ECDSA) {
+            printf("KEYPAIR ECDSA\r\n");
+            mbedtls_ecp_group_id gid = get_ec_group_id_from_attr(algo + 1, algo_len - 1);
+            if (gid == MBEDTLS_ECP_DP_NONE) {
+                return SW_FUNC_NOT_SUPPORTED();
+            }
+            mbedtls_ecdsa_context ecdsa;
+            mbedtls_ecdsa_init(&ecdsa);
+            uint8_t index = 0;
+            r = mbedtls_ecdsa_genkey(&ecdsa, gid, random_gen, &index);
+            if (r != 0) {
+                mbedtls_ecdsa_free(&ecdsa);
+                return SW_EXEC_ERROR();
+            }
+            r = store_keys(&ecdsa, algo[0], fid, true);
+            make_ecdsa_response(&ecdsa);
+            mbedtls_ecdsa_free(&ecdsa);
+            if (r != PICOKEY_OK) {
+                return SW_EXEC_ERROR();
+            }
+        }
+        else {
+            return SW_FUNC_NOT_SUPPORTED();
+        }
+        file_t *pbef = search_by_fid(fid + 3, NULL, SPECIFY_EF);
+        if (!pbef) {
+            return SW_REFERENCE_NOT_FOUND();
+        }
+        r = file_put_data(pbef, res_APDU, res_APDU_size);
+        if (r != PICOKEY_OK) {
+            return SW_EXEC_ERROR();
+        }
+        if (fid == EF_PK_SIG) {
+            reset_sig_count();
+        }
+        else if (fid == EF_PK_DEC) {
+            // OpenPGP does not allow generating AES keys. So, we generate a new one when gen for DEC is called.
+            // It is a 256 AES key by default.
+            uint8_t aes_key[32]; //maximum AES key size
+            uint8_t key_size = 32;
+            memcpy(aes_key, random_bytes_get(key_size), key_size);
+            r = store_keys(aes_key, ALGO_AES_256, EF_AES_KEY, true);
+            /* if storing the key fails, we silently continue */
+            //if (r != PICOKEY_OK)
+            //    return SW_EXEC_ERROR();
+        }
+        low_flash_available();
+        return SW_OK();
+    }
+    else if (P1(apdu) == 0x81) { //read
+        file_t *ef = search_by_fid(fid + 3, NULL, SPECIFY_EF);
+        if (!ef || !ef->data) {
+            return SW_REFERENCE_NOT_FOUND();
+        }
+        res_APDU_size = file_get_size(ef);
+        memcpy(res_APDU, file_get_data(ef), res_APDU_size);
+        return SW_OK();
+    }
+    return SW_INCORRECT_P1P2();
+}