diff options
Diffstat (limited to '')
| -rw-r--r-- | src/pcsc.c | 394 |
1 files changed, 394 insertions, 0 deletions
diff --git a/src/pcsc.c b/src/pcsc.c new file mode 100644 index 0000000..d7bd6c6 --- /dev/null +++ b/src/pcsc.c @@ -0,0 +1,394 @@ +/* + * Copyright (c) 2022 Micro Focus or one of its affiliates. + * Copyright (c) 2022 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. + * SPDX-License-Identifier: BSD-2-Clause + */ + +#if __APPLE__ +#include <PCSC/wintypes.h> +#include <PCSC/winscard.h> +#else +#include <winscard.h> +#endif /* __APPLE__ */ + +#include <errno.h> + +#include "fido.h" +#include "fido/param.h" +#include "iso7816.h" + +#if defined(_WIN32) && !defined(__MINGW32__) +#define SCardConnect SCardConnectA +#define SCardListReaders SCardListReadersA +#endif + +#ifndef SCARD_PROTOCOL_Tx +#define SCARD_PROTOCOL_Tx SCARD_PROTOCOL_ANY +#endif + +#define BUFSIZE 1024 /* in bytes; passed to SCardListReaders() */ +#define APDULEN 264 /* 261 rounded up to the nearest multiple of 8 */ +#define READERS 8 /* maximum number of readers */ + +struct pcsc { + SCARDCONTEXT ctx; + SCARDHANDLE h; + SCARD_IO_REQUEST req; + uint8_t rx_buf[APDULEN]; + size_t rx_len; +}; + +static LONG +list_readers(SCARDCONTEXT ctx, char **buf) +{ + LONG s; + DWORD len; + + len = BUFSIZE; + if ((*buf = calloc(1, len)) == NULL) + goto fail; + if ((s = SCardListReaders(ctx, NULL, *buf, &len)) != SCARD_S_SUCCESS) { + fido_log_debug("%s: SCardListReaders 0x%lx", __func__, (long)s); + goto fail; + } + /* sanity check "multi-string" */ + if (len > BUFSIZE || len < 2) { + fido_log_debug("%s: bogus len=%u", __func__, (unsigned)len); + goto fail; + } + if ((*buf)[len - 1] != 0 || (*buf)[len - 2] != '\0') { + fido_log_debug("%s: bogus buf", __func__); + goto fail; + } + return (LONG)SCARD_S_SUCCESS; +fail: + free(*buf); + *buf = NULL; + + return (LONG)SCARD_E_NO_READERS_AVAILABLE; +} + +static char * +get_reader(SCARDCONTEXT ctx, const char *path) +{ + char *reader = NULL, *buf = NULL; + const char prefix[] = FIDO_PCSC_PREFIX "//slot"; + uint64_t n; + + if (path == NULL) + goto out; + if (strncmp(path, prefix, strlen(prefix)) != 0 || + fido_to_uint64(path + strlen(prefix), 10, &n) < 0 || + n > READERS - 1) { + fido_log_debug("%s: invalid path %s", __func__, path); + goto out; + } + if (list_readers(ctx, &buf) != SCARD_S_SUCCESS) { + fido_log_debug("%s: list_readers", __func__); + goto out; + } + for (const char *name = buf; *name != 0; name += strlen(name) + 1) { + if (n == 0) { + reader = strdup(name); + goto out; + } + n--; + } + fido_log_debug("%s: failed to find reader %s", __func__, path); +out: + free(buf); + + return reader; +} + +static int +prepare_io_request(DWORD prot, SCARD_IO_REQUEST *req) +{ + switch (prot) { + case SCARD_PROTOCOL_T0: + req->dwProtocol = SCARD_PCI_T0->dwProtocol; + req->cbPciLength = SCARD_PCI_T0->cbPciLength; + break; + case SCARD_PROTOCOL_T1: + req->dwProtocol = SCARD_PCI_T1->dwProtocol; + req->cbPciLength = SCARD_PCI_T1->cbPciLength; + break; + default: + fido_log_debug("%s: unknown protocol %lu", __func__, + (u_long)prot); + return -1; + } + + return 0; +} + +static int +copy_info(fido_dev_info_t *di, SCARDCONTEXT ctx, const char *reader, size_t idx) +{ + SCARDHANDLE h = 0; + SCARD_IO_REQUEST req; + DWORD prot = 0; + LONG s; + int ok = -1; + + memset(di, 0, sizeof(*di)); + memset(&req, 0, sizeof(req)); + + if ((s = SCardConnect(ctx, reader, SCARD_SHARE_SHARED, + SCARD_PROTOCOL_Tx, &h, &prot)) != SCARD_S_SUCCESS) { + fido_log_debug("%s: SCardConnect 0x%lx", __func__, (long)s); + goto fail; + } + if (prepare_io_request(prot, &req) < 0) { + fido_log_debug("%s: prepare_io_request", __func__); + goto fail; + } + if (asprintf(&di->path, "%s//slot%zu", FIDO_PCSC_PREFIX, idx) == -1) { + di->path = NULL; + fido_log_debug("%s: asprintf", __func__); + goto fail; + } + if (nfc_is_fido(di->path) == false) { + fido_log_debug("%s: nfc_is_fido: %s", __func__, di->path); + goto fail; + } + if ((di->manufacturer = strdup("PC/SC")) == NULL || + (di->product = strdup(reader)) == NULL) + goto fail; + + ok = 0; +fail: + if (h != 0) + SCardDisconnect(h, SCARD_LEAVE_CARD); + if (ok < 0) { + free(di->path); + free(di->manufacturer); + free(di->product); + explicit_bzero(di, sizeof(*di)); + } + + return ok; +} + +int +fido_pcsc_manifest(fido_dev_info_t *devlist, size_t ilen, size_t *olen) +{ + SCARDCONTEXT ctx = 0; + char *buf = NULL; + LONG s; + size_t idx = 0; + int r = FIDO_ERR_INTERNAL; + + *olen = 0; + + if (ilen == 0) + return FIDO_OK; + if (devlist == NULL) + return FIDO_ERR_INVALID_ARGUMENT; + + if ((s = SCardEstablishContext(SCARD_SCOPE_SYSTEM, NULL, NULL, + &ctx)) != SCARD_S_SUCCESS || ctx == 0) { + fido_log_debug("%s: SCardEstablishContext 0x%lx", __func__, + (long)s); + if (s == (LONG)SCARD_E_NO_SERVICE || + s == (LONG)SCARD_E_NO_SMARTCARD) + r = FIDO_OK; /* suppress error */ + goto out; + } + if ((s = list_readers(ctx, &buf)) != SCARD_S_SUCCESS) { + fido_log_debug("%s: list_readers 0x%lx", __func__, (long)s); + if (s == (LONG)SCARD_E_NO_READERS_AVAILABLE) + r = FIDO_OK; /* suppress error */ + goto out; + } + + for (const char *name = buf; *name != 0; name += strlen(name) + 1) { + if (idx == READERS) { + fido_log_debug("%s: stopping at %zu readers", __func__, + idx); + r = FIDO_OK; + goto out; + } + if (copy_info(&devlist[*olen], ctx, name, idx++) == 0) { + devlist[*olen].io = (fido_dev_io_t) { + fido_pcsc_open, + fido_pcsc_close, + fido_pcsc_read, + fido_pcsc_write, + }; + devlist[*olen].transport = (fido_dev_transport_t) { + fido_pcsc_rx, + fido_pcsc_tx, + }; + if (++(*olen) == ilen) + break; + } + } + + r = FIDO_OK; +out: + free(buf); + if (ctx != 0) + SCardReleaseContext(ctx); + + return r; +} + +void * +fido_pcsc_open(const char *path) +{ + char *reader = NULL; + struct pcsc *dev = NULL; + SCARDCONTEXT ctx = 0; + SCARDHANDLE h = 0; + SCARD_IO_REQUEST req; + DWORD prot = 0; + LONG s; + + memset(&req, 0, sizeof(req)); + + if ((s = SCardEstablishContext(SCARD_SCOPE_SYSTEM, NULL, NULL, + &ctx)) != SCARD_S_SUCCESS || ctx == 0) { + fido_log_debug("%s: SCardEstablishContext 0x%lx", __func__, + (long)s); + goto fail; + + } + if ((reader = get_reader(ctx, path)) == NULL) { + fido_log_debug("%s: get_reader(%s)", __func__, path); + goto fail; + } + if ((s = SCardConnect(ctx, reader, SCARD_SHARE_SHARED, + SCARD_PROTOCOL_Tx, &h, &prot)) != SCARD_S_SUCCESS) { + fido_log_debug("%s: SCardConnect 0x%lx", __func__, (long)s); + goto fail; + } + if (prepare_io_request(prot, &req) < 0) { + fido_log_debug("%s: prepare_io_request", __func__); + goto fail; + } + if ((dev = calloc(1, sizeof(*dev))) == NULL) + goto fail; + + dev->ctx = ctx; + dev->h = h; + dev->req = req; + ctx = 0; + h = 0; +fail: + if (h != 0) + SCardDisconnect(h, SCARD_LEAVE_CARD); + if (ctx != 0) + SCardReleaseContext(ctx); + free(reader); + + return dev; +} + +void +fido_pcsc_close(void *handle) +{ + struct pcsc *dev = handle; + + if (dev->h != 0) + SCardDisconnect(dev->h, SCARD_LEAVE_CARD); + if (dev->ctx != 0) + SCardReleaseContext(dev->ctx); + + explicit_bzero(dev->rx_buf, sizeof(dev->rx_buf)); + free(dev); +} + +int +fido_pcsc_read(void *handle, unsigned char *buf, size_t len, int ms) +{ + struct pcsc *dev = handle; + int r; + + (void)ms; + if (dev->rx_len == 0 || dev->rx_len > len || + dev->rx_len > sizeof(dev->rx_buf)) { + fido_log_debug("%s: rx_len", __func__); + return -1; + } + fido_log_xxd(dev->rx_buf, dev->rx_len, "%s: reading", __func__); + memcpy(buf, dev->rx_buf, dev->rx_len); + explicit_bzero(dev->rx_buf, sizeof(dev->rx_buf)); + r = (int)dev->rx_len; + dev->rx_len = 0; + + return r; +} + +int +fido_pcsc_write(void *handle, const unsigned char *buf, size_t len) +{ + struct pcsc *dev = handle; + DWORD n; + LONG s; + + if (len > INT_MAX) { + fido_log_debug("%s: len", __func__); + return -1; + } + + explicit_bzero(dev->rx_buf, sizeof(dev->rx_buf)); + dev->rx_len = 0; + n = (DWORD)sizeof(dev->rx_buf); + + fido_log_xxd(buf, len, "%s: writing", __func__); + + if ((s = SCardTransmit(dev->h, &dev->req, buf, (DWORD)len, NULL, + dev->rx_buf, &n)) != SCARD_S_SUCCESS) { + fido_log_debug("%s: SCardTransmit 0x%lx", __func__, (long)s); + explicit_bzero(dev->rx_buf, sizeof(dev->rx_buf)); + return -1; + } + dev->rx_len = (size_t)n; + + fido_log_xxd(dev->rx_buf, dev->rx_len, "%s: read", __func__); + + return (int)len; +} + +int +fido_pcsc_tx(fido_dev_t *d, uint8_t cmd, const u_char *buf, size_t count) +{ + return fido_nfc_tx(d, cmd, buf, count); +} + +int +fido_pcsc_rx(fido_dev_t *d, uint8_t cmd, u_char *buf, size_t count, int ms) +{ + return fido_nfc_rx(d, cmd, buf, count, ms); +} + +bool +fido_is_pcsc(const char *path) +{ + return strncmp(path, FIDO_PCSC_PREFIX, strlen(FIDO_PCSC_PREFIX)) == 0; +} + +int +fido_dev_set_pcsc(fido_dev_t *d) +{ + if (d->io_handle != NULL) { + fido_log_debug("%s: device open", __func__); + return -1; + } + d->io_own = true; + d->io = (fido_dev_io_t) { + fido_pcsc_open, + fido_pcsc_close, + fido_pcsc_read, + fido_pcsc_write, + }; + d->transport = (fido_dev_transport_t) { + fido_pcsc_rx, + fido_pcsc_tx, + }; + + return 0; +} |