diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7e105d4..63ccae8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -61,6 +61,7 @@ target_sources(pico_fido PUBLIC
         ${CMAKE_CURRENT_LIST_DIR}/src/fido/credential.c
         ${CMAKE_CURRENT_LIST_DIR}/src/fido/cbor_get_assertion.c
         ${CMAKE_CURRENT_LIST_DIR}/src/fido/cbor_selection.c
+        ${CMAKE_CURRENT_LIST_DIR}/src/fido/cbor_cred_mgmt.c
         )
 set(HSM_DRIVER "hid")
 include(pico-hsm-sdk/pico_hsm_sdk_import.cmake)
diff --git a/src/fido/cbor_cred_mgmt.c b/src/fido/cbor_cred_mgmt.c
new file mode 100644
index 0000000..1f529b3
--- /dev/null
+++ b/src/fido/cbor_cred_mgmt.c
@@ -0,0 +1,206 @@
+
+/*
+ * This file is part of the Pico FIDO distribution (https://github.com/polhenarejos/pico-fido).
+ * 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 "ctap2_cbor.h"
+#include "fido.h"
+#include "ctap.h"
+#include "bsp/board.h"
+#include "cbor_make_credential.h"
+#include "files.h"
+#include "apdu.h"
+
+uint8_t rp_counter = 1;
+uint8_t rp_total = 0;
+uint8_t cred_counter = 1;
+uint8_t cred_total = 0;
+
+int cbor_cred_mgmt(const uint8_t *data, size_t len) {
+    CborParser parser;
+    CborValue map;
+    CborError error = CborNoError;
+    uint64_t subcommand = 0, pinUvAuthProtocol = 0;
+    CborByteString pinUvAuthParam = {0}, rpIdHash = {0};
+    PublicKeyCredentialDescriptor credentialId = {0};
+    PublicKeyCredentialUserEntity user = {0};
+    size_t resp_size = 0;
+    CborEncoder encoder, mapEncoder, mapEncoder2;
+
+    CBOR_CHECK(cbor_parser_init(data, len, 0, &parser, &map));
+    uint64_t val_c = 1;
+    CBOR_PARSE_MAP_START(map, 1) {
+        uint64_t val_u = 0;
+        CBOR_FIELD_GET_UINT(val_u, 1);
+        if (val_c <= 4 && val_c != val_u)
+            CBOR_ERROR(CTAP2_ERR_MISSING_PARAMETER);
+        if (val_u < val_c)
+            CBOR_ERROR(CTAP2_ERR_INVALID_CBOR);
+        val_c = val_u + 1;
+        if (val_u == 0x01) {
+            CBOR_FIELD_GET_UINT(subcommand, 1);
+        }
+        else if (val_u == 0x02) {
+            uint64_t subpara = 0;
+            CBOR_PARSE_MAP_START(_f1, 2) {
+                CBOR_FIELD_GET_UINT(subpara, 2);
+                if (subpara == 0x01) {
+                    CBOR_FIELD_GET_BYTES(rpIdHash, 2);
+                }
+                else if (subpara == 0x02) {
+                    CBOR_PARSE_MAP_START(_f2, 3) {
+                        CBOR_FIELD_GET_KEY_TEXT(3);
+                        CBOR_FIELD_KEY_TEXT_VAL_BYTES(3, "id", credentialId.id);
+                        CBOR_FIELD_KEY_TEXT_VAL_TEXT(3, "type", credentialId.type);
+                        if (strcmp(_fd3, "transports") == 0) {
+                            CBOR_PARSE_ARRAY_START(_f3, 4) {
+                                CBOR_FIELD_GET_TEXT(credentialId.transports[credentialId.transports_len], 4);
+                                credentialId.transports_len++;
+                            }
+                            CBOR_PARSE_ARRAY_END(_f3, 4);
+                        }
+                    }
+                    CBOR_PARSE_MAP_END(_f2, 3);
+                }
+                else if (subpara == 0x03) {
+                    CBOR_PARSE_MAP_START(_f1, 3) {
+                        CBOR_FIELD_GET_KEY_TEXT(3);
+                        CBOR_FIELD_KEY_TEXT_VAL_BYTES(3, "id", user.id);
+                        CBOR_FIELD_KEY_TEXT_VAL_TEXT(3, "name", user.parent.name);
+                        CBOR_FIELD_KEY_TEXT_VAL_TEXT(3, "displayName", user.displayName);
+                    }
+                    CBOR_PARSE_MAP_END(_f1, 3);
+                }
+            }
+            CBOR_PARSE_MAP_END(_f1, 2);
+        }
+        else if (val_u == 0x03) {
+            CBOR_FIELD_GET_UINT(pinUvAuthProtocol, 1);
+        }
+        else if (val_u == 0x04) { // pubKeyCredParams
+            CBOR_FIELD_GET_BYTES(pinUvAuthParam, 1);
+        }
+    }
+    CBOR_PARSE_MAP_END(map, 1);
+
+    if (subcommand != 0x03) {
+        if (pinUvAuthParam.present == false)
+            CBOR_ERROR(CTAP2_ERR_PUAT_REQUIRED);
+        if (pinUvAuthProtocol != 1 && pinUvAuthProtocol != 2)
+            CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
+    }
+
+    cbor_encoder_init(&encoder, ctap_resp->init.data + 1, CTAP_MAX_PACKET_SIZE, 0);
+    if(subcommand == 0x01) {
+        if (verify(pinUvAuthProtocol, paut.data, (const uint8_t *)"\x01", 1, pinUvAuthParam.data) != CborNoError)
+            CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
+        uint8_t existing = 0;
+        for (int i = 0; i < MAX_RESIDENT_CREDENTIALS; i++) {
+            if (file_has_data(search_dynamic_file(EF_CRED + i)))
+                existing++;
+        }
+        CBOR_CHECK(cbor_encoder_create_map(&encoder, &mapEncoder, 2));
+        CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x01));
+        CBOR_CHECK(cbor_encode_uint(&mapEncoder, existing));
+        CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x02));
+        CBOR_CHECK(cbor_encode_uint(&mapEncoder, MAX_RESIDENT_CREDENTIALS-existing));
+    }
+    else if (subcommand == 0x02 || subcommand == 0x03) {
+        file_t *rp_ef = NULL;
+        if (subcommand == 0x02) {
+            if (verify(pinUvAuthProtocol, paut.data, (const uint8_t *)"\x02", 1, pinUvAuthParam.data) != CborNoError)
+                CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
+        }
+        else {
+            if (rp_counter >= rp_total)
+                CBOR_ERROR(CTAP2_ERR_NOT_ALLOWED);
+        }
+        uint8_t skip = 0;
+        for (int i = 0; i < MAX_RESIDENT_CREDENTIALS; i++) {
+            file_t *tef = search_dynamic_file(EF_RP + i);
+            if (file_has_data(tef)) {
+                if (++skip == rp_counter) {
+                    if (rp_ef == NULL)
+                        rp_ef = tef;
+                    if (subcommand == 0x03)
+                        break;
+                }
+                rp_total++;
+            }
+        }
+        if (rp_ef == NULL) // should not happen
+            CBOR_ERROR(CTAP2_ERR_OPERATION_DENIED);
+        CBOR_CHECK(cbor_encoder_create_map(&encoder, &mapEncoder, subcommand == 0x02 ? 3 : 2));
+        CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x03));
+        CBOR_CHECK(cbor_encoder_create_map(&mapEncoder, &mapEncoder2, 1));
+        CBOR_CHECK(cbor_encode_text_stringz(&mapEncoder2, "id"));
+        CBOR_CHECK(cbor_encode_byte_string(&mapEncoder2, file_get_data(rp_ef)+33, file_get_size(rp_ef)-33));
+        CBOR_CHECK(cbor_encoder_close_container(&mapEncoder, &mapEncoder2));
+        CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x04));
+        CBOR_CHECK(cbor_encode_byte_string(&mapEncoder, file_get_data(rp_ef)+1, 32));
+        if (subcommand == 0x02) {
+            CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x05));
+            CBOR_CHECK(cbor_encode_uint(&mapEncoder, rp_total));
+        }
+    }
+    else if (subcommand == 0x04) {
+        uint8_t submap[37];
+        submap[0] = 0x04;
+        memcpy(submap + 1, "\xA1\x01\x58\x20", 4);
+        memcpy(submap + 1 + 4, rpIdHash.data, 32);
+        if (verify(pinUvAuthProtocol, paut.data, submap, sizeof(submap), pinUvAuthParam.data) != CborNoError)
+            CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
+        file_t *cred_ef = NULL;
+        for (int i = 0; i < MAX_RESIDENT_CREDENTIALS; i++) {
+            file_t *tef = search_dynamic_file(EF_CRED + i);
+            if (file_has_data(tef) && memcmp(file_get_data(tef), rpIdHash.data, 32) == 0) {
+                cred_ef = tef;
+                break;
+            }
+        }
+        if (!file_has_data(rp_ef) || *file_get_data(rp_ef) == 0)
+            CBOR_ERROR(CTAP2_ERR_NO_CREDENTIALS);
+        CBOR_CHECK(cbor_encoder_create_map(&encoder, &mapEncoder,  5));
+
+    }
+    else if (subcommand == 0x05) {
+
+    }
+    else if (subcommand == 0x06) {
+
+    }
+    else if (subcommand == 0x07) {
+
+    }
+    CBOR_CHECK(cbor_encoder_close_container(&encoder, &mapEncoder));
+    resp_size = cbor_encoder_get_buffer_size(&encoder, ctap_resp->init.data + 1);
+    err:
+    CBOR_FREE_BYTE_STRING(pinUvAuthParam);
+
+    CBOR_FREE_BYTE_STRING(rpIdHash);
+    CBOR_FREE_BYTE_STRING(user.id);
+    CBOR_FREE_BYTE_STRING(user.displayName);
+    CBOR_FREE_BYTE_STRING(user.parent.name);
+    CBOR_FREE_BYTE_STRING(credentialId.type);
+
+    if (error != CborNoError) {
+        if (error == CborErrorImproperValue)
+            return CTAP2_ERR_CBOR_UNEXPECTED_TYPE;
+        return error;
+    }
+    res_APDU_size = resp_size;
+    return 0;
+}
diff --git a/src/fido/credential.c b/src/fido/credential.c
index b68daa3..2642b20 100644
--- a/src/fido/credential.c
+++ b/src/fido/credential.c
@@ -234,12 +234,46 @@ int credential_store(const uint8_t *cred_id, size_t cred_id_len, const uint8_t *
     }
     if (sloti == -1)
         return -1;
-    credential_free(&cred);
     uint8_t *data = (uint8_t *)calloc(1, cred_id_len+32);
     memcpy(data, rp_id_hash, 32);
     memcpy(data + 32, cred_id, cred_id_len);
     file_t *ef = file_new(EF_CRED+sloti);
     flash_write_data_to_file(ef, data, cred_id_len + 32);
+    free(data);
+
+    sloti = -1;
+    for (int i = 0; i < MAX_RESIDENT_CREDENTIALS; i++) {
+        ef = search_dynamic_file(EF_RP + i);
+        if (!file_has_data(ef)) {
+            if (sloti == -1)
+                sloti = i;
+            continue;
+        }
+        if (memcmp(file_get_data(ef)+1, rp_id_hash, 32) == 0) {
+            sloti = i;
+            break;
+        }
+    }
+    if (sloti == -1)
+        return -1;
+    ef = search_dynamic_file(EF_RP + sloti);
+    if (file_has_data(ef)) {
+        data = (uint8_t *)calloc(1, file_get_size(ef));
+        memcpy(data, file_get_data(ef), file_get_size(ef));
+        data[0] += 1;
+        flash_write_data_to_file(ef, data, file_get_size(ef));
+        free(data);
+    }
+    else {
+        ef = file_new(EF_RP+sloti);
+        data = (uint8_t *)calloc(1, 1 + 32 + cred.rpId.len);
+        data[0] = 0;
+        memcpy(data+1, rp_id_hash, 32);
+        memcpy(data + 1 + 32, cred.rpId.data, cred.rpId.len);
+        flash_write_data_to_file(ef, data, 1 + 32 + cred.rpId.len);
+        free(data);
+    }
+    credential_free(&cred);
     low_flash_available();
     return 0;
 }
diff --git a/src/fido/files.h b/src/fido/files.h
index 858a23e..998d2a3 100644
--- a/src/fido/files.h
+++ b/src/fido/files.h
@@ -26,6 +26,7 @@
 #define EF_PIN          0x1080
 #define EF_AUTHTOKEN    0x1090
 #define EF_CRED         0xCF00 // Creds at 0xCF00 - 0xCFFF
+#define EF_RP           0xD000 // RPs at 0xD000 - 0xD0FF
 
 extern file_t *ef_keydev;
 extern file_t *ef_certdev;