diff options
Diffstat (limited to 'lib/libfido2/src/pin.c')
| -rw-r--r-- | lib/libfido2/src/pin.c | 428 |
1 files changed, 428 insertions, 0 deletions
diff --git a/lib/libfido2/src/pin.c b/lib/libfido2/src/pin.c new file mode 100644 index 00000000000..5789cd86ea7 --- /dev/null +++ b/lib/libfido2/src/pin.c @@ -0,0 +1,428 @@ +/* + * Copyright (c) 2018 Yubico AB. All rights reserved. + * Use of this source code is governed by a BSD-style + * license that can be found in the LICENSE file. + */ + +#include <string.h> +#include "fido.h" +#include "fido/es256.h" + +static int +parse_pintoken(const cbor_item_t *key, const cbor_item_t *val, void *arg) +{ + fido_blob_t *token = arg; + + if (cbor_isa_uint(key) == false || + cbor_int_get_width(key) != CBOR_INT_8 || + cbor_get_uint8(key) != 2) { + log_debug("%s: cbor type", __func__); + return (0); /* ignore */ + } + + return (fido_blob_decode(val, token)); +} + +static int +fido_dev_get_pin_token_tx(fido_dev_t *dev, const char *pin, + const fido_blob_t *ecdh, const es256_pk_t *pk) +{ + fido_blob_t f; + fido_blob_t *p = NULL; + cbor_item_t *argv[6]; + int r; + + memset(&f, 0, sizeof(f)); + memset(argv, 0, sizeof(argv)); + + if ((p = fido_blob_new()) == NULL || fido_blob_set(p, + (const unsigned char *)pin, strlen(pin)) < 0) { + log_debug("%s: fido_blob_set", __func__); + r = FIDO_ERR_INVALID_ARGUMENT; + goto fail; + } + + if ((argv[0] = cbor_build_uint8(1)) == NULL || + (argv[1] = cbor_build_uint8(5)) == NULL || + (argv[2] = es256_pk_encode(pk, 0)) == NULL || + (argv[5] = encode_pin_hash_enc(ecdh, p)) == NULL) { + log_debug("%s: cbor encode", __func__); + r = FIDO_ERR_INTERNAL; + goto fail; + } + + if (cbor_build_frame(CTAP_CBOR_CLIENT_PIN, argv, 6, &f) < 0 || + tx(dev, CTAP_FRAME_INIT | CTAP_CMD_CBOR, f.ptr, f.len) < 0) { + log_debug("%s: tx", __func__); + r = FIDO_ERR_TX; + goto fail; + } + + r = FIDO_OK; +fail: + cbor_vector_free(argv, nitems(argv)); + fido_blob_free(&p); + free(f.ptr); + + return (r); +} + +static int +fido_dev_get_pin_token_rx(fido_dev_t *dev, const fido_blob_t *ecdh, + fido_blob_t *token, int ms) +{ + const uint8_t cmd = CTAP_FRAME_INIT | CTAP_CMD_CBOR; + fido_blob_t *aes_token = NULL; + unsigned char reply[2048]; + int reply_len; + int r; + + if ((aes_token = fido_blob_new()) == NULL) { + r = FIDO_ERR_INTERNAL; + goto fail; + } + + if ((reply_len = rx(dev, cmd, &reply, sizeof(reply), ms)) < 0) { + log_debug("%s: rx", __func__); + r = FIDO_ERR_RX; + goto fail; + } + + if ((r = parse_cbor_reply(reply, (size_t)reply_len, aes_token, + parse_pintoken)) != FIDO_OK) { + log_debug("%s: parse_pintoken", __func__); + goto fail; + } + + if (aes256_cbc_dec(ecdh, aes_token, token) < 0) { + log_debug("%s: aes256_cbc_dec", __func__); + r = FIDO_ERR_RX; + goto fail; + } + + r = FIDO_OK; +fail: + fido_blob_free(&aes_token); + + return (r); +} + +static int +fido_dev_get_pin_token_wait(fido_dev_t *dev, const char *pin, + const fido_blob_t *ecdh, const es256_pk_t *pk, fido_blob_t *token, int ms) +{ + int r; + + if ((r = fido_dev_get_pin_token_tx(dev, pin, ecdh, pk)) != FIDO_OK || + (r = fido_dev_get_pin_token_rx(dev, ecdh, token, ms)) != FIDO_OK) + return (r); + + return (FIDO_OK); +} + +int +fido_dev_get_pin_token(fido_dev_t *dev, const char *pin, + const fido_blob_t *ecdh, const es256_pk_t *pk, fido_blob_t *token) +{ + return (fido_dev_get_pin_token_wait(dev, pin, ecdh, pk, token, -1)); +} + +static int +pad64(const char *pin, fido_blob_t **ppin) +{ + size_t pin_len; + size_t ppin_len; + + pin_len = strlen(pin); + if (pin_len < 4 || pin_len > 255) { + log_debug("%s: invalid pin length", __func__); + return (FIDO_ERR_PIN_POLICY_VIOLATION); + } + + if ((*ppin = fido_blob_new()) == NULL) + return (FIDO_ERR_INTERNAL); + + ppin_len = (pin_len + 63) & ~63; + if (ppin_len < pin_len || ((*ppin)->ptr = calloc(1, ppin_len)) == NULL) { + fido_blob_free(ppin); + return (FIDO_ERR_INTERNAL); + } + + memcpy((*ppin)->ptr, pin, pin_len); + (*ppin)->len = ppin_len; + + return (FIDO_OK); +} + +static int +fido_dev_change_pin_tx(fido_dev_t *dev, const char *pin, const char *oldpin) +{ + fido_blob_t f; + fido_blob_t *ppin = NULL; + fido_blob_t *ecdh = NULL; + fido_blob_t *opin = NULL; + cbor_item_t *argv[6]; + es256_pk_t *pk = NULL; + int r; + + memset(&f, 0, sizeof(f)); + memset(argv, 0, sizeof(argv)); + + if ((opin = fido_blob_new()) == NULL || fido_blob_set(opin, + (const unsigned char *)oldpin, strlen(oldpin)) < 0) { + log_debug("%s: fido_blob_set", __func__); + r = FIDO_ERR_INVALID_ARGUMENT; + goto fail; + } + + if ((r = pad64(pin, &ppin)) != FIDO_OK) { + log_debug("%s: pad64", __func__); + goto fail; + } + + if ((r = fido_do_ecdh(dev, &pk, &ecdh)) != FIDO_OK) { + log_debug("%s: fido_do_ecdh", __func__); + goto fail; + } + + if ((argv[0] = cbor_build_uint8(1)) == NULL || + (argv[1] = cbor_build_uint8(4)) == NULL || + (argv[2] = es256_pk_encode(pk, 0)) == NULL || + (argv[3] = encode_change_pin_auth(ecdh, ppin, opin)) == NULL || + (argv[4] = encode_pin_enc(ecdh, ppin)) == NULL || + (argv[5] = encode_pin_hash_enc(ecdh, opin)) == NULL) { + log_debug("%s: cbor encode", __func__); + r = FIDO_ERR_INTERNAL; + goto fail; + } + + if (cbor_build_frame(CTAP_CBOR_CLIENT_PIN, argv, 6, &f) < 0 || + tx(dev, CTAP_FRAME_INIT | CTAP_CMD_CBOR, f.ptr, f.len) < 0) { + log_debug("%s: tx", __func__); + r = FIDO_ERR_TX; + goto fail; + } + + r = FIDO_OK; +fail: + cbor_vector_free(argv, nitems(argv)); + es256_pk_free(&pk); + fido_blob_free(&ppin); + fido_blob_free(&ecdh); + fido_blob_free(&opin); + free(f.ptr); + + return (r); + +} + +static int +fido_dev_set_pin_tx(fido_dev_t *dev, const char *pin) +{ + fido_blob_t f; + fido_blob_t *ppin = NULL; + fido_blob_t *ecdh = NULL; + cbor_item_t *argv[5]; + es256_pk_t *pk = NULL; + int r; + + memset(&f, 0, sizeof(f)); + memset(argv, 0, sizeof(argv)); + + if ((r = pad64(pin, &ppin)) != FIDO_OK) { + log_debug("%s: pad64", __func__); + goto fail; + } + + if ((r = fido_do_ecdh(dev, &pk, &ecdh)) != FIDO_OK) { + log_debug("%s: fido_do_ecdh", __func__); + goto fail; + } + + if ((argv[0] = cbor_build_uint8(1)) == NULL || + (argv[1] = cbor_build_uint8(3)) == NULL || + (argv[2] = es256_pk_encode(pk, 0)) == NULL || + (argv[3] = encode_set_pin_auth(ecdh, ppin)) == NULL || + (argv[4] = encode_pin_enc(ecdh, ppin)) == NULL) { + log_debug("%s: cbor encode", __func__); + r = FIDO_ERR_INTERNAL; + goto fail; + } + + if (cbor_build_frame(CTAP_CBOR_CLIENT_PIN, argv, 5, &f) < 0 || + tx(dev, CTAP_FRAME_INIT | CTAP_CMD_CBOR, f.ptr, f.len) < 0) { + log_debug("%s: tx", __func__); + r = FIDO_ERR_TX; + goto fail; + } + + r = FIDO_OK; +fail: + cbor_vector_free(argv, nitems(argv)); + es256_pk_free(&pk); + fido_blob_free(&ppin); + fido_blob_free(&ecdh); + free(f.ptr); + + return (r); +} + +static int +fido_dev_set_pin_wait(fido_dev_t *dev, const char *pin, const char *oldpin, + int ms) +{ + int r; + + if (oldpin != NULL) { + if ((r = fido_dev_change_pin_tx(dev, pin, oldpin)) != FIDO_OK) { + log_debug("%s: fido_dev_change_pin_tx", __func__); + return (r); + } + } else { + if ((r = fido_dev_set_pin_tx(dev, pin)) != FIDO_OK) { + log_debug("%s: fido_dev_set_pin_tx", __func__); + return (r); + } + } + + if ((r = rx_cbor_status(dev, ms)) != FIDO_OK) { + log_debug("%s: rx_cbor_status", __func__); + return (r); + } + + return (FIDO_OK); +} + +int +fido_dev_set_pin(fido_dev_t *dev, const char *pin, const char *oldpin) +{ + return (fido_dev_set_pin_wait(dev, pin, oldpin, -1)); +} + +static int +parse_retry_count(const cbor_item_t *key, const cbor_item_t *val, void *arg) +{ + int *retries = arg; + uint64_t n; + + if (cbor_isa_uint(key) == false || + cbor_int_get_width(key) != CBOR_INT_8 || + cbor_get_uint8(key) != 3) { + log_debug("%s: cbor type", __func__); + return (0); /* ignore */ + } + + if (decode_uint64(val, &n) < 0 || n > INT_MAX) { + log_debug("%s: decode_uint64", __func__); + return (-1); + } + + *retries = (int)n; + + return (0); +} + +static int +fido_dev_get_retry_count_tx(fido_dev_t *dev) +{ + fido_blob_t f; + cbor_item_t *argv[2]; + int r; + + memset(&f, 0, sizeof(f)); + memset(argv, 0, sizeof(argv)); + + if ((argv[0] = cbor_build_uint8(1)) == NULL || + (argv[1] = cbor_build_uint8(1)) == NULL) { + r = FIDO_ERR_INTERNAL; + goto fail; + } + + if (cbor_build_frame(CTAP_CBOR_CLIENT_PIN, argv, 2, &f) < 0 || + tx(dev, CTAP_FRAME_INIT | CTAP_CMD_CBOR, f.ptr, f.len) < 0) { + log_debug("%s: tx", __func__); + r = FIDO_ERR_TX; + goto fail; + } + + r = FIDO_OK; +fail: + cbor_vector_free(argv, nitems(argv)); + free(f.ptr); + + return (r); +} + +static int +fido_dev_get_retry_count_rx(fido_dev_t *dev, int *retries, int ms) +{ + const uint8_t cmd = CTAP_FRAME_INIT | CTAP_CMD_CBOR; + unsigned char reply[512]; + int reply_len; + int r; + + *retries = 0; + + if ((reply_len = rx(dev, cmd, &reply, sizeof(reply), ms)) < 0) { + log_debug("%s: rx", __func__); + return (FIDO_ERR_RX); + } + + if ((r = parse_cbor_reply(reply, (size_t)reply_len, retries, + parse_retry_count)) != FIDO_OK) { + log_debug("%s: parse_retry_count", __func__); + return (r); + } + + return (FIDO_OK); +} + +static int +fido_dev_get_retry_count_wait(fido_dev_t *dev, int *retries, int ms) +{ + int r; + + if ((r = fido_dev_get_retry_count_tx(dev)) != FIDO_OK || + (r = fido_dev_get_retry_count_rx(dev, retries, ms)) != FIDO_OK) + return (r); + + return (FIDO_OK); +} + +int +fido_dev_get_retry_count(fido_dev_t *dev, int *retries) +{ + return (fido_dev_get_retry_count_wait(dev, retries, -1)); +} + +int +add_cbor_pin_params(fido_dev_t *dev, const fido_blob_t *hmac_data, + const es256_pk_t *pk, const fido_blob_t *ecdh, const char *pin, + cbor_item_t **auth, cbor_item_t **opt) +{ + fido_blob_t *token = NULL; + int r; + + if ((token = fido_blob_new()) == NULL) { + r = FIDO_ERR_INTERNAL; + goto fail; + } + + if ((r = fido_dev_get_pin_token(dev, pin, ecdh, pk, token)) != FIDO_OK) { + log_debug("%s: fido_dev_get_pin_token", __func__); + goto fail; + } + + if ((*auth = encode_pin_auth(token, hmac_data)) == NULL || + (*opt = encode_pin_opt()) == NULL) { + log_debug("%s: cbor encode", __func__); + r = FIDO_ERR_INTERNAL; + goto fail; + } + + r = FIDO_OK; +fail: + fido_blob_free(&token); + + return (r); +} |