diff --git a/client/Makefile b/client/Makefile
index 6c04a752..4a4dd65a 100644
--- a/client/Makefile
+++ b/client/Makefile
@@ -110,6 +110,10 @@ CMDSRCS = 	crapto1/crapto1.c\
 			ui.c \
 			cmddata.c \
 			lfdemod.c \
+			emv/crypto.c\
+			emv/emv_pk.c\
+			emv/emv_pki.c\
+			emv/emv_pki_priv.c\
 			emv/apduinfo.c\
 			emv/dump.c\
 			emv/tlv.c\
diff --git a/client/emv/crypto.c b/client/emv/crypto.c
new file mode 100644
index 00000000..a40e1a6b
--- /dev/null
+++ b/client/emv/crypto.c
@@ -0,0 +1,181 @@
+/*
+ * libopenemv - a library to work with EMV family of smart cards
+ * Copyright (C) 2015 Dmitry Eremin-Solenikov
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "crypto.h"
+#include "crypto_backend.h"
+
+#include <string.h>
+
+static struct crypto_backend *crypto_backend;
+
+static bool crypto_init(void)
+{
+	//const char *driver;
+
+	if (crypto_backend)
+		return true;
+
+	//	crypto_backend = crypto_nettle_init(); TODO!!!!!
+
+	if (!crypto_backend)
+		return false;
+
+	return true;
+}
+
+struct crypto_hash *crypto_hash_open(enum crypto_algo_hash hash)
+{
+	struct crypto_hash *ch;
+
+	if (!crypto_init())
+		return NULL;
+
+	ch = crypto_backend->hash_open(hash);
+	if (ch)
+		ch->algo = hash;
+
+	return ch;
+}
+
+void crypto_hash_close(struct crypto_hash *ch)
+{
+	ch->close(ch);
+}
+
+void crypto_hash_write(struct crypto_hash *ch, const unsigned char *buf, size_t len)
+{
+	ch->write(ch, buf, len);
+}
+
+unsigned char *crypto_hash_read(struct crypto_hash *ch)
+{
+	return ch->read(ch);
+}
+
+size_t crypto_hash_get_size(const struct crypto_hash *ch)
+{
+	return ch->get_size(ch);
+}
+
+struct crypto_pk *crypto_pk_open(enum crypto_algo_pk pk, ...)
+{
+	struct crypto_pk *cp;
+	va_list vl;
+
+	if (!crypto_init())
+		return NULL;
+
+	va_start(vl, pk);
+	cp = crypto_backend->pk_open(pk, vl);
+	va_end(vl);
+
+	if (cp)
+		cp->algo = pk;
+
+	return cp;
+}
+
+struct crypto_pk *crypto_pk_open_priv(enum crypto_algo_pk pk, ...)
+{
+	struct crypto_pk *cp;
+	va_list vl;
+
+	if (!crypto_init())
+		return NULL;
+
+	if (!crypto_backend->pk_open_priv)
+		return NULL;
+
+	va_start(vl, pk);
+	cp = crypto_backend->pk_open_priv(pk, vl);
+	va_end(vl);
+
+	if (cp)
+		cp->algo = pk;
+
+	return cp;
+}
+
+struct crypto_pk *crypto_pk_genkey(enum crypto_algo_pk pk, ...)
+{
+	struct crypto_pk *cp;
+	va_list vl;
+
+	if (!crypto_init())
+		return NULL;
+
+	if (!crypto_backend->pk_genkey)
+		return NULL;
+
+	va_start(vl, pk);
+	cp = crypto_backend->pk_genkey(pk, vl);
+	va_end(vl);
+
+	if (cp)
+		cp->algo = pk;
+
+	return cp;
+}
+
+void crypto_pk_close(struct crypto_pk *cp)
+{
+	cp->close(cp);
+}
+
+unsigned char *crypto_pk_encrypt(const struct crypto_pk *cp, const unsigned char *buf, size_t len, size_t *clen)
+{
+	return cp->encrypt(cp, buf, len, clen);
+}
+
+unsigned char *crypto_pk_decrypt(const struct crypto_pk *cp, const unsigned char *buf, size_t len, size_t *clen)
+{
+	if (!cp->decrypt) {
+		*clen = 0;
+
+		return NULL;
+	}
+
+	return cp->decrypt(cp, buf, len, clen);
+}
+
+enum crypto_algo_pk crypto_pk_get_algo(const struct crypto_pk *cp)
+{
+	if (!cp)
+		return PK_INVALID;
+
+	return cp->algo;
+}
+
+size_t crypto_pk_get_nbits(const struct crypto_pk *cp)
+{
+	if (!cp->get_nbits)
+		return 0;
+
+	return cp->get_nbits(cp);
+}
+
+unsigned char *crypto_pk_get_parameter(const struct crypto_pk *cp, unsigned param, size_t *plen)
+{
+	*plen = 0;
+
+	if (!cp->get_parameter)
+		return NULL;
+
+	return cp->get_parameter(cp, param, plen);
+}
diff --git a/client/emv/crypto.h b/client/emv/crypto.h
new file mode 100644
index 00000000..940e8b2b
--- /dev/null
+++ b/client/emv/crypto.h
@@ -0,0 +1,48 @@
+/*
+ * libopenemv - a library to work with EMV family of smart cards
+ * Copyright (C) 2015 Dmitry Eremin-Solenikov
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ */
+
+#ifndef CRYPTO_H
+#define CRYPTO_H
+
+#include <stdbool.h>
+#include <stddef.h>
+
+enum crypto_algo_hash {
+	HASH_INVALID,
+	HASH_SHA_1,
+};
+
+struct crypto_hash *crypto_hash_open(enum crypto_algo_hash hash);
+void crypto_hash_close(struct crypto_hash *ch);
+void crypto_hash_write(struct crypto_hash *ch, const unsigned char *buf, size_t len);
+unsigned char *crypto_hash_read(struct crypto_hash *ch);
+size_t crypto_hash_get_size(const struct crypto_hash *ch);
+
+enum crypto_algo_pk {
+	PK_INVALID,
+	PK_RSA,
+};
+
+struct crypto_pk *crypto_pk_open(enum crypto_algo_pk pk, ...);
+struct crypto_pk *crypto_pk_open_priv(enum crypto_algo_pk pk, ...);
+struct crypto_pk *crypto_pk_genkey(enum crypto_algo_pk pk, ...);
+void crypto_pk_close(struct crypto_pk *cp);
+unsigned char *crypto_pk_encrypt(const struct crypto_pk *cp, const unsigned char *buf, size_t len, size_t *clen);
+unsigned char *crypto_pk_decrypt(const struct crypto_pk *cp, const unsigned char *buf, size_t len, size_t *clen);
+enum crypto_algo_pk crypto_pk_get_algo(const struct crypto_pk *cp);
+size_t crypto_pk_get_nbits(const struct crypto_pk *cp);
+unsigned char *crypto_pk_get_parameter(const struct crypto_pk *cp, unsigned param, size_t *plen);
+
+#endif
diff --git a/client/emv/crypto_backend.h b/client/emv/crypto_backend.h
new file mode 100644
index 00000000..79273c0a
--- /dev/null
+++ b/client/emv/crypto_backend.h
@@ -0,0 +1,48 @@
+/*
+ * libopenemv - a library to work with EMV family of smart cards
+ * Copyright (C) 2015 Dmitry Eremin-Solenikov
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ */
+
+#ifndef CRYPTO_BACKEND_H
+#define CRYPTO_BACKEND_H
+
+#include "crypto.h"
+
+#include <stddef.h>
+#include <stdarg.h>
+
+struct crypto_hash {
+	enum crypto_algo_hash algo;
+	void (*write)(struct crypto_hash *ch, const unsigned char *buf, size_t len);
+	unsigned char *(*read)(struct crypto_hash *ch);
+	void (*close)(struct crypto_hash *ch);
+	size_t (*get_size)(const struct crypto_hash *ch);
+};
+
+struct crypto_pk {
+	enum crypto_algo_pk algo;
+	unsigned char *(*encrypt)(const struct crypto_pk *cp, const unsigned char *buf, size_t len, size_t *clen);
+	unsigned char *(*decrypt)(const struct crypto_pk *cp, const unsigned char *buf, size_t len, size_t *clen);
+	unsigned char *(*get_parameter)(const struct crypto_pk *cp, unsigned param, size_t *plen);
+	size_t (*get_nbits)(const struct crypto_pk *cp);
+	void (*close)(struct crypto_pk *cp);
+};
+
+struct crypto_backend {
+	struct crypto_hash *(*hash_open)(enum crypto_algo_hash hash);
+	struct crypto_pk *(*pk_open)(enum crypto_algo_pk pk, va_list vl);
+	struct crypto_pk *(*pk_open_priv)(enum crypto_algo_pk pk, va_list vl);
+	struct crypto_pk *(*pk_genkey)(enum crypto_algo_pk pk, va_list vl);
+};
+
+#endif
diff --git a/client/emv/crypto_libgcrypt.c b/client/emv/crypto_libgcrypt.c
new file mode 100644
index 00000000..03bcf45b
--- /dev/null
+++ b/client/emv/crypto_libgcrypt.c
@@ -0,0 +1,532 @@
+/*
+ * libopenemv - a library to work with EMV family of smart cards
+ * Copyright (C) 2015 Dmitry Eremin-Solenikov
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "openemv/crypto.h"
+#include "crypto_backend.h"
+
+#include <stdarg.h>
+#include <stdio.h>
+
+#define GCRYPT_NO_DEPRECATED
+#define GCRYPT_NO_MPI_MACROS
+#include <gcrypt.h>
+
+struct crypto_hash_libgcrypt {
+	struct crypto_hash ch;
+	gcry_md_hd_t md;
+};
+
+static void crypto_hash_libgcrypt_close(struct crypto_hash *_ch)
+{
+	struct crypto_hash_libgcrypt *ch = container_of(_ch, struct crypto_hash_libgcrypt, ch);
+
+	gcry_md_close(ch->md);
+	free(ch);
+}
+
+static void crypto_hash_libgcrypt_write(struct crypto_hash *_ch, const unsigned char *buf, size_t len)
+{
+	struct crypto_hash_libgcrypt *ch = container_of(_ch, struct crypto_hash_libgcrypt, ch);
+
+	gcry_md_write(ch->md, buf, len);
+}
+
+static unsigned char *crypto_hash_libgcrypt_read(struct crypto_hash *_ch)
+{
+	struct crypto_hash_libgcrypt *ch = container_of(_ch, struct crypto_hash_libgcrypt, ch);
+
+	return gcry_md_read(ch->md, 0);
+}
+
+static size_t crypto_hash_libgcrypt_get_size(const struct crypto_hash *ch)
+{
+	int algo = GCRY_MD_NONE;
+
+	if (ch->algo == HASH_SHA_1)
+		algo = GCRY_MD_SHA1;
+
+	return gcry_md_get_algo_dlen(algo);
+}
+
+static struct crypto_hash *crypto_hash_libgcrypt_open(enum crypto_algo_hash hash)
+{
+	struct crypto_hash_libgcrypt *ch = malloc(sizeof(*ch));
+	gcry_error_t err;
+	int algo = GCRY_MD_NONE;
+
+	if (hash == HASH_SHA_1)
+		algo = GCRY_MD_SHA1;
+
+	err = gcry_md_open(&ch->md, algo, 0);
+	if (err) {
+		fprintf(stderr, "LibGCrypt error %s/%s\n",
+				gcry_strsource (err),
+				gcry_strerror (err));
+		free(ch);
+
+		return NULL;
+	}
+
+	ch->ch.write = crypto_hash_libgcrypt_write;
+	ch->ch.read = crypto_hash_libgcrypt_read;
+	ch->ch.close = crypto_hash_libgcrypt_close;
+	ch->ch.get_size = crypto_hash_libgcrypt_get_size;
+
+	return &ch->ch;
+}
+
+struct crypto_pk_libgcrypt {
+	struct crypto_pk cp;
+	gcry_sexp_t pk;
+};
+
+static struct crypto_pk *crypto_pk_libgcrypt_open_rsa(va_list vl)
+{
+	struct crypto_pk_libgcrypt *cp = malloc(sizeof(*cp));
+	gcry_error_t err;
+	char *mod = va_arg(vl, char *);
+	int modlen = va_arg(vl, size_t);
+	char *exp = va_arg(vl, char *);
+	int explen = va_arg(vl, size_t);
+
+	err = gcry_sexp_build(&cp->pk, NULL, "(public-key (rsa (n %b) (e %b)))",
+			modlen, mod, explen, exp);
+	if (err) {
+		fprintf(stderr, "LibGCrypt error %s/%s\n",
+				gcry_strsource (err),
+				gcry_strerror (err));
+		free(cp);
+		return NULL;
+	}
+
+	return &cp->cp;
+}
+
+static struct crypto_pk *crypto_pk_libgcrypt_open_priv_rsa(va_list vl)
+{
+	struct crypto_pk_libgcrypt *cp = malloc(sizeof(*cp));
+	gcry_error_t err;
+	char *mod = va_arg(vl, char *);
+	int modlen = va_arg(vl, size_t);
+	char *exp = va_arg(vl, char *);
+	int explen = va_arg(vl, size_t);
+	char *d = va_arg(vl, char *);
+	int dlen = va_arg(vl, size_t);
+	char *p = va_arg(vl, char *);
+	int plen = va_arg(vl, size_t);
+	gcry_mpi_t pmpi;
+	char *q = va_arg(vl, char *);
+	int qlen = va_arg(vl, size_t);
+	gcry_mpi_t qmpi;
+	(void) va_arg(vl, char *);
+	(void) va_arg(vl, size_t);
+	(void) va_arg(vl, char *);
+	(void) va_arg(vl, size_t);
+	char *inv = va_arg(vl, char *);
+	int invlen = va_arg(vl, size_t);
+	gcry_mpi_t invmpi;
+
+	err = gcry_mpi_scan(&pmpi, GCRYMPI_FMT_USG, p, plen, NULL);
+	if (err)
+		goto err_p;
+
+	err = gcry_mpi_scan(&qmpi, GCRYMPI_FMT_USG, q, qlen, NULL);
+	if (err)
+		goto err_q;
+
+	err = gcry_mpi_scan(&invmpi, GCRYMPI_FMT_USG, inv, invlen, NULL);
+	if (err)
+		goto err_inv;
+
+	if (gcry_mpi_cmp (pmpi, qmpi) > 0) {
+		gcry_mpi_swap (pmpi, qmpi);
+		gcry_mpi_invm (invmpi, pmpi, qmpi);
+	}
+
+	err = gcry_sexp_build(&cp->pk, NULL, "(private-key (rsa (n %b) (e %b) (d %b) (p %M) (q %M) (u %M)))",
+			modlen, mod, explen, exp, dlen, d,
+			pmpi, qmpi, invmpi);
+	if (err)
+		goto err_sexp;
+
+	err = gcry_pk_testkey(cp->pk);
+	if (err)
+		goto err_test;
+
+	gcry_mpi_release(invmpi);
+	gcry_mpi_release(qmpi);
+	gcry_mpi_release(pmpi);
+
+	return &cp->cp;
+
+err_test:
+	gcry_sexp_release(cp->pk);
+err_sexp:
+	gcry_mpi_release(invmpi);
+err_inv:
+	gcry_mpi_release(qmpi);
+err_q:
+	gcry_mpi_release(pmpi);
+err_p:
+	free(cp);
+
+	fprintf(stderr, "LibGCrypt error %s/%s\n",
+			gcry_strsource (err),
+			gcry_strerror (err));
+	return NULL;
+}
+
+static struct crypto_pk *crypto_pk_libgcrypt_genkey_rsa(va_list vl)
+{
+	struct crypto_pk_libgcrypt *cp = malloc(sizeof(*cp));
+	gcry_error_t err;
+	gcry_sexp_t params;
+	int transient = va_arg(vl, int);
+	unsigned int nbits = va_arg(vl, unsigned int);
+	unsigned int exp = va_arg(vl, unsigned int);
+
+	err = gcry_sexp_build(&params, NULL,
+			transient ?
+			"(genkey (rsa (nbits %u) (rsa-use-e %u) (flags transient-key)))":
+			"(genkey (rsa (nbits %u) (rsa-use-e %u)))",
+			nbits, exp);
+	if (err) {
+		fprintf(stderr, "LibGCrypt error %s/%s\n",
+				gcry_strsource (err),
+				gcry_strerror (err));
+		free(cp);
+		return NULL;
+	}
+
+	err = gcry_pk_genkey(&cp->pk, params);
+	gcry_sexp_release(params);
+	if (err) {
+		fprintf(stderr, "LibGCrypt error %s/%s\n",
+				gcry_strsource (err),
+				gcry_strerror (err));
+		free(cp);
+		return NULL;
+	}
+
+	return &cp->cp;
+}
+
+static void crypto_pk_libgcrypt_close(struct crypto_pk *_cp)
+{
+	struct crypto_pk_libgcrypt *cp = container_of(_cp, struct crypto_pk_libgcrypt, cp);
+
+	gcry_sexp_release(cp->pk);
+	free(cp);
+}
+
+static unsigned char *crypto_pk_libgcrypt_encrypt(const struct crypto_pk *_cp, const unsigned char *buf, size_t len, size_t *clen)
+{
+	struct crypto_pk_libgcrypt *cp = container_of(_cp, struct crypto_pk_libgcrypt, cp);
+	gcry_error_t err;
+	int blen = len;
+	gcry_sexp_t dsexp, esexp, asexp;
+	gcry_mpi_t tmpi;
+	size_t templen;
+	size_t keysize;
+	unsigned char *result;
+
+	err = gcry_sexp_build(&dsexp, NULL, "(data (flags raw) (value %b))",
+			blen, buf);
+	if (err) {
+		fprintf(stderr, "LibGCrypt error %s/%s\n",
+				gcry_strsource (err),
+				gcry_strerror (err));
+		return NULL;
+	}
+
+	err = gcry_pk_encrypt(&esexp, dsexp, cp->pk);
+	gcry_sexp_release(dsexp);
+	if (err) {
+		fprintf(stderr, "LibGCrypt error %s/%s\n",
+				gcry_strsource (err),
+				gcry_strerror (err));
+		return NULL;
+	}
+
+	asexp = gcry_sexp_find_token(esexp, "a", 1);
+	gcry_sexp_release(esexp);
+	if (!asexp)
+		return NULL;
+
+	tmpi = gcry_sexp_nth_mpi(asexp, 1, GCRYMPI_FMT_USG);
+	gcry_sexp_release(asexp);
+	if (!tmpi)
+		return NULL;
+
+	keysize = (gcry_pk_get_nbits(cp->pk) + 7) / 8;
+	result = malloc(keysize);
+	if (!result) {
+		gcry_mpi_release(tmpi);
+		return NULL;
+	}
+
+	err = gcry_mpi_print(GCRYMPI_FMT_USG, NULL, keysize, &templen, tmpi);
+	if (err) {
+		fprintf(stderr, "LibGCrypt error %s/%s\n",
+				gcry_strsource (err),
+				gcry_strerror (err));
+		gcry_mpi_release(tmpi);
+		free(result);
+		return NULL;
+	}
+
+	err = gcry_mpi_print(GCRYMPI_FMT_USG, result + keysize - templen, templen, &templen, tmpi);
+	if (err) {
+		fprintf(stderr, "LibGCrypt error %s/%s\n",
+				gcry_strsource (err),
+				gcry_strerror (err));
+		gcry_mpi_release(tmpi);
+		free(result);
+		return NULL;
+	}
+	memset(result, 0, keysize - templen);
+
+	*clen = keysize;
+	gcry_mpi_release(tmpi);
+
+	return result;
+}
+
+static unsigned char *crypto_pk_libgcrypt_decrypt(const struct crypto_pk *_cp, const unsigned char *buf, size_t len, size_t *clen)
+{
+	struct crypto_pk_libgcrypt *cp = container_of(_cp, struct crypto_pk_libgcrypt, cp);
+	gcry_error_t err;
+	int blen = len;
+	gcry_sexp_t esexp, dsexp;
+	gcry_mpi_t tmpi;
+	size_t templen;
+	size_t keysize;
+	unsigned char *result;
+
+	/* XXX: RSA-only! */
+	err = gcry_sexp_build(&esexp, NULL, "(enc-val (flags) (rsa (a %b)))",
+			blen, buf);
+	if (err) {
+		fprintf(stderr, "LibGCrypt error %s/%s\n",
+				gcry_strsource (err),
+				gcry_strerror (err));
+		return NULL;
+	}
+
+	err = gcry_pk_decrypt(&dsexp, esexp, cp->pk);
+	gcry_sexp_release(esexp);
+	if (err) {
+		fprintf(stderr, "LibGCrypt error %s/%s\n",
+				gcry_strsource (err),
+				gcry_strerror (err));
+		return NULL;
+	}
+
+	tmpi = gcry_sexp_nth_mpi(dsexp, 1, GCRYMPI_FMT_USG);
+	gcry_sexp_release(dsexp);
+	if (!tmpi)
+		return NULL;
+
+	keysize = (gcry_pk_get_nbits(cp->pk) + 7) / 8;
+	result = malloc(keysize);
+	if (!result) {
+		gcry_mpi_release(tmpi);
+		return NULL;
+	}
+
+	err = gcry_mpi_print(GCRYMPI_FMT_USG, NULL, keysize, &templen, tmpi);
+	if (err) {
+		fprintf(stderr, "LibGCrypt error %s/%s\n",
+				gcry_strsource (err),
+				gcry_strerror (err));
+		gcry_mpi_release(tmpi);
+		free(result);
+		return NULL;
+	}
+
+	err = gcry_mpi_print(GCRYMPI_FMT_USG, result + keysize - templen, templen, &templen, tmpi);
+	if (err) {
+		fprintf(stderr, "LibGCrypt error %s/%s\n",
+				gcry_strsource (err),
+				gcry_strerror (err));
+		gcry_mpi_release(tmpi);
+		free(result);
+		return NULL;
+	}
+	memset(result, 0, keysize - templen);
+
+	*clen = keysize;
+	gcry_mpi_release(tmpi);
+
+	return result;
+}
+
+static size_t crypto_pk_libgcrypt_get_nbits(const struct crypto_pk *_cp)
+{
+	struct crypto_pk_libgcrypt *cp = container_of(_cp, struct crypto_pk_libgcrypt, cp);
+
+	return gcry_pk_get_nbits(cp->pk);
+}
+
+static unsigned char *crypto_pk_libgcrypt_get_parameter(const struct crypto_pk *_cp, unsigned param, size_t *plen)
+{
+	struct crypto_pk_libgcrypt *cp = container_of(_cp, struct crypto_pk_libgcrypt, cp);
+	gcry_error_t err;
+	gcry_sexp_t psexp;
+	gcry_mpi_t tmpi;
+	size_t parameter_size;
+	unsigned char *result;
+	const char *name;
+
+	/* XXX: RSA-only! */
+	if (param == 0)
+		name = "n";
+	else if (param == 1)
+		name = "e";
+	else
+		return NULL;
+
+	psexp = gcry_sexp_find_token(cp->pk, name, 1);
+	if (!psexp)
+		return NULL;
+
+	tmpi = gcry_sexp_nth_mpi(psexp, 1, GCRYMPI_FMT_USG);
+	gcry_sexp_release(psexp);
+	if (!tmpi)
+		return NULL;
+
+	parameter_size = (gcry_mpi_get_nbits(tmpi) + 7) / 8;
+	result = malloc(parameter_size);
+	if (!result) {
+		gcry_mpi_release(tmpi);
+		return NULL;
+	}
+
+	err = gcry_mpi_print(GCRYMPI_FMT_USG, result, parameter_size, NULL, tmpi);
+	if (err) {
+		fprintf(stderr, "LibGCrypt error %s/%s\n",
+				gcry_strsource (err),
+				gcry_strerror (err));
+		gcry_mpi_release(tmpi);
+		free(result);
+		return NULL;
+	}
+
+	*plen = parameter_size;
+	gcry_mpi_release(tmpi);
+
+	return result;
+}
+
+static struct crypto_pk *crypto_pk_libgcrypt_open(enum crypto_algo_pk pk, va_list vl)
+{
+	struct crypto_pk *cp;
+
+	if (pk == PK_RSA)
+		cp = crypto_pk_libgcrypt_open_rsa(vl);
+	else
+		return NULL;
+
+	cp->close = crypto_pk_libgcrypt_close;
+	cp->encrypt = crypto_pk_libgcrypt_encrypt;
+	cp->get_parameter = crypto_pk_libgcrypt_get_parameter;
+	cp->get_nbits = crypto_pk_libgcrypt_get_nbits;
+
+	return cp;
+}
+
+static struct crypto_pk *crypto_pk_libgcrypt_open_priv(enum crypto_algo_pk pk, va_list vl)
+{
+	struct crypto_pk *cp;
+
+	if (pk == PK_RSA)
+		cp = crypto_pk_libgcrypt_open_priv_rsa(vl);
+	else
+		return NULL;
+
+	cp->close = crypto_pk_libgcrypt_close;
+	cp->encrypt = crypto_pk_libgcrypt_encrypt;
+	cp->decrypt = crypto_pk_libgcrypt_decrypt;
+	cp->get_parameter = crypto_pk_libgcrypt_get_parameter;
+	cp->get_nbits = crypto_pk_libgcrypt_get_nbits;
+
+	return cp;
+}
+
+static struct crypto_pk *crypto_pk_libgcrypt_genkey(enum crypto_algo_pk pk, va_list vl)
+{
+	struct crypto_pk *cp;
+
+	if (pk == PK_RSA)
+		cp = crypto_pk_libgcrypt_genkey_rsa(vl);
+	else
+		return NULL;
+
+	cp->close = crypto_pk_libgcrypt_close;
+	cp->encrypt = crypto_pk_libgcrypt_encrypt;
+	cp->decrypt = crypto_pk_libgcrypt_decrypt;
+	cp->get_parameter = crypto_pk_libgcrypt_get_parameter;
+	cp->get_nbits = crypto_pk_libgcrypt_get_nbits;
+
+	return cp;
+}
+
+static struct crypto_backend crypto_libgcrypt_backend = {
+	.hash_open = crypto_hash_libgcrypt_open,
+	.pk_open = crypto_pk_libgcrypt_open,
+	.pk_open_priv = crypto_pk_libgcrypt_open_priv,
+	.pk_genkey = crypto_pk_libgcrypt_genkey,
+};
+
+struct crypto_backend *crypto_libgcrypt_init(void)
+{
+	/* Version check should be the very first call because it
+	 * makes sure that important subsystems are intialized. */
+	if (!gcry_check_version (GCRYPT_VERSION)) {
+		fputs ("libgcrypt version mismatch\n", stderr);
+		return NULL;
+	}
+
+	/* We don't want to see any warnings, e.g. because we have not yet
+	 * parsed program options which might be used to suppress such
+	 * warnings. */
+	gcry_control (GCRYCTL_SUSPEND_SECMEM_WARN);
+
+	/* ... If required, other initialization goes here.  Note that the
+	 * process might still be running with increased privileges and that
+	 * the secure memory has not been intialized.  */
+
+	/* Allocate a pool of 16k secure memory.  This make the secure memory
+	 * available and also drops privileges where needed.  */
+	gcry_control (GCRYCTL_INIT_SECMEM, 16384, 0);
+
+	/* It is now okay to let Libgcrypt complain when there was/is
+	 * a problem with the secure memory. */
+	gcry_control (GCRYCTL_RESUME_SECMEM_WARN);
+
+	/* ... If required, other initialization goes here.  */
+
+	/* Tell Libgcrypt that initialization has completed. */
+	gcry_control (GCRYCTL_INITIALIZATION_FINISHED, 0);
+
+//	gcry_control (GCRYCTL_SET_DEBUG_FLAGS, 3u , 0);
+//	gcry_control (GCRYCTL_PRINT_CONFIG, stdout);
+
+	return &crypto_libgcrypt_backend;
+}
diff --git a/client/emv/emv_pk.c b/client/emv/emv_pk.c
new file mode 100644
index 00000000..d9b3ac32
--- /dev/null
+++ b/client/emv/emv_pk.c
@@ -0,0 +1,521 @@
+/*
+ * libopenemv - a library to work with EMV family of smart cards
+ * Copyright (C) 2012, 2015 Dmitry Eremin-Solenikov
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "emv_pk.h"
+#include "crypto.h"
+
+/* For asprintf */
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdbool.h>
+#include <string.h>
+#include <stdlib.h>
+
+#define BCD(c) (((c) >= '0' && (c) <= '9') ? ((c) - '0') : \
+		-1)
+
+#define HEX(c) (((c) >= '0' && (c) <= '9') ? ((c) - '0') : \
+		((c) >= 'A' && (c) <= 'F') ? ((c) - 'A' + 10) : \
+		((c) >= 'a' && (c) <= 'f') ? ((c) - 'a' + 10) : \
+		-1)
+
+#define TOHEX(v) ((v) < 10 ? (v) + '0' : (v) - 10 + 'a')
+
+static ssize_t emv_pk_read_bin(char *buf, unsigned char *bin, size_t size, size_t *read)
+{
+	size_t left = size;
+	char *p = buf;
+	while (*p && *p == ' ')
+		p++;
+
+	while (left > 0) {
+		int c1, c2;
+		c1 = HEX(*p);
+		if (c1 == -1)
+			return -(p - buf);
+		p++;
+		c2 = HEX(*p);
+		if (c2 == -1)
+			return -(p - buf);
+		p++;
+		*bin = (c1 * 16 + c2);
+		bin ++;
+		left --;
+		if (*p == ':')
+			p++;
+		else if (read) {
+			*read = (size - left);
+			break;
+		} else if (left == 0)
+			break;
+		else
+			return -(p - buf);
+	}
+
+	while (*p && *p == ' ')
+		p++;
+
+	p--;
+
+	return (p - buf);
+}
+
+static ssize_t emv_pk_read_ymv(char *buf, unsigned *ymv)
+{
+	int i;
+	unsigned char temp[3];
+	char *p = buf;
+
+	*ymv = 0;
+
+	while (*p && *p == ' ')
+		p++;
+
+	for (i = 0; i < 3; i++) {
+		int c1, c2;
+		c1 = BCD(*p);
+		if (c1 == -1)
+			return -(p - buf);
+		p++;
+		c2 = BCD(*p);
+		if (c2 == -1)
+			return -(p - buf);
+		p++;
+		temp[i] = (c1 * 16 + c2);
+	}
+
+	while (*p && *p == ' ')
+		p++;
+
+	p--;
+
+	if (temp[1] > 0x12 || temp[2] > 0x31)
+		return -(p - buf);
+
+	*ymv = (temp[0] * 0x10000 + temp[1] * 0x100 + temp[2]);
+
+	return (p - buf);
+}
+
+static ssize_t emv_pk_read_string(char *buf, char *str, size_t size)
+{
+	char *p = buf;
+	while (*p && *p == ' ')
+		p++;
+
+	while (size > 1) {
+		if (*p == ' ')
+			break;
+		else if (*p < 0x20 || *p >= 0x7f)
+			return -(p - buf);
+		*str = *p;
+		p++;
+		str ++;
+		size --;
+	}
+
+	*str = 0;
+
+	while (*p && *p == ' ')
+		p++;
+
+	p--;
+
+	return (p - buf);
+}
+
+
+struct emv_pk *emv_pk_parse_pk(char *buf)
+{
+	struct emv_pk *r = calloc(1, sizeof(*r));
+	ssize_t l;
+	char temp[10];
+
+	l = emv_pk_read_bin(buf, r->rid, 5, NULL);
+	if (l <= 0)
+		goto out;
+	buf += l;
+
+	l = emv_pk_read_bin(buf, &r->index, 1, NULL);
+	if (l <= 0)
+		goto out;
+	buf += l;
+
+	l = emv_pk_read_ymv(buf, &r->expire);
+	if (l <= 0)
+		goto out;
+	buf += l;
+
+	l = emv_pk_read_string(buf, temp, sizeof(temp));
+	if (l <= 0)
+		goto out;
+	buf += l;
+
+	if (!strcmp(temp, "rsa"))
+		r->pk_algo = PK_RSA;
+	else
+		goto out;
+
+	l = emv_pk_read_bin(buf, r->exp, sizeof(r->exp), &r->elen);
+	if (l <= 0)
+		goto out;
+	buf += l;
+
+	r->modulus = malloc(2048/8);
+	l = emv_pk_read_bin(buf, r->modulus, 2048/8, &r->mlen);
+	if (l <= 0)
+		goto out2;
+	buf += l;
+
+	l = emv_pk_read_string(buf, temp, sizeof(temp));
+	if (l <= 0)
+		goto out2;
+	buf += l;
+
+	if (!strcmp(temp, "sha1"))
+		r->hash_algo = HASH_SHA_1;
+	else
+		goto out2;
+
+	l = emv_pk_read_bin(buf, r->hash, 20, NULL);
+	if (l <= 0)
+		goto out2;
+
+	return r;
+
+out2:
+	free(r->modulus);
+out:
+	free(r);
+	return NULL;
+}
+
+static size_t emv_pk_write_bin(char *out, size_t outlen, const unsigned char *buf, size_t len)
+{
+	int i;
+	size_t pos = 0;
+
+	if (len == 0)
+		return 0;
+	if (outlen < len * 3)
+		return 0;
+
+	out[pos++] = TOHEX(buf[0] >> 4);
+	out[pos++] = TOHEX(buf[0] & 0xf);
+	for (i = 1; i < len; i++) {
+		out[pos++] = ':';
+		out[pos++] = TOHEX(buf[i] >> 4);
+		out[pos++] = TOHEX(buf[i] & 0xf);
+	}
+	out[pos++] = ' ';
+
+	return pos;
+}
+
+static size_t emv_pk_write_str(char *out, size_t outlen, const char *str)
+{
+	size_t len = strlen(str);
+
+	if (len == 0)
+		return 0;
+	if (outlen < len)
+		return 0;
+
+	memcpy(out, str, len);
+
+	return len;
+}
+
+char *emv_pk_dump_pk(const struct emv_pk *pk)
+{
+	size_t outsize = 1024; /* should be enough */
+	char *out = malloc(outsize); /* should be enough */
+	size_t outpos = 0;
+	size_t rc;
+
+	if (!out)
+		return NULL;
+
+	rc = emv_pk_write_bin(out + outpos, outsize - outpos, pk->rid, 5);
+	if (rc == 0)
+		goto err;
+	outpos += rc;
+
+	rc = emv_pk_write_bin(out + outpos, outsize - outpos, &pk->index, 1);
+	if (rc == 0)
+		goto err;
+	outpos += rc;
+
+	if (outpos + 7 > outsize)
+		goto err;
+	out[outpos++] = TOHEX((pk->expire >> 20) & 0xf);
+	out[outpos++] = TOHEX((pk->expire >> 16) & 0xf);
+	out[outpos++] = TOHEX((pk->expire >> 12) & 0xf);
+	out[outpos++] = TOHEX((pk->expire >> 8 ) & 0xf);
+	out[outpos++] = TOHEX((pk->expire >> 4 ) & 0xf);
+	out[outpos++] = TOHEX((pk->expire >> 0 ) & 0xf);
+	out[outpos++] = ' ';
+
+	if (pk->pk_algo == PK_RSA) {
+		rc = emv_pk_write_str(out + outpos, outsize - outpos, "rsa");
+		if (rc == 0)
+			goto err;
+		outpos += rc;
+		out[outpos++] = ' ';
+	} else {
+		if (outpos + 4 > outsize)
+			goto err;
+		out[outpos++] = '?';
+		out[outpos++] = '?';
+		out[outpos++] = TOHEX(pk->pk_algo >> 4);
+		out[outpos++] = TOHEX(pk->pk_algo & 0xf);
+	}
+
+	rc = emv_pk_write_bin(out + outpos, outsize - outpos, pk->exp, pk->elen);
+	if (rc == 0)
+		goto err;
+	outpos += rc;
+
+	rc = emv_pk_write_bin(out + outpos, outsize - outpos, pk->modulus, pk->mlen);
+	if (rc == 0)
+		goto err;
+	outpos += rc;
+
+	if (pk->hash_algo == HASH_SHA_1) {
+		rc = emv_pk_write_str(out + outpos, outsize - outpos, "sha1");
+		if (rc == 0)
+			goto err;
+		outpos += rc;
+		out[outpos++] = ' ';
+	} else {
+		if (outpos + 4 > outsize)
+			goto err;
+		out[outpos++] = '?';
+		out[outpos++] = '?';
+		out[outpos++] = TOHEX(pk->pk_algo >> 4);
+		out[outpos++] = TOHEX(pk->pk_algo & 0xf);
+	}
+
+
+	rc = emv_pk_write_bin(out + outpos, outsize - outpos, pk->hash, 20);
+	if (rc == 0)
+		goto err;
+	outpos += rc;
+
+	out[outpos-1] = '\0';
+
+	return out;
+
+err:
+	free(out);
+	return NULL;
+}
+
+bool emv_pk_verify(const struct emv_pk *pk)
+{
+	struct crypto_hash *ch = crypto_hash_open(pk->hash_algo);
+	if (!ch)
+		return false;
+
+	crypto_hash_write(ch, pk->rid, sizeof(pk->rid));
+	crypto_hash_write(ch, &pk->index, 1);
+	crypto_hash_write(ch, pk->modulus, pk->mlen);
+	crypto_hash_write(ch, pk->exp, pk->elen);
+
+	unsigned char *h = crypto_hash_read(ch);
+	if (!h) {
+		crypto_hash_close(ch);
+		return false;
+	}
+
+	size_t hsize = crypto_hash_get_size(ch);
+	bool r = hsize && !memcmp(h, pk->hash, hsize) ? true : false;
+
+	crypto_hash_close(ch);
+
+	return r;
+}
+
+struct emv_pk *emv_pk_new(size_t modlen, size_t explen)
+{
+	struct emv_pk *pk;
+
+	/* Not supported ATM */
+	if (explen > 3)
+		return NULL;
+
+	pk = calloc(1, sizeof(*pk));
+	if (!pk)
+		return NULL;
+
+	pk->mlen = modlen;
+	pk->elen = explen;
+
+	pk->modulus = calloc(modlen, 1);
+	if (!pk->modulus) {
+		free(pk);
+		pk = NULL;
+	}
+
+	return pk;
+}
+
+void emv_pk_free(struct emv_pk *pk)
+{
+	if (!pk)
+		return;
+
+	free(pk->modulus);
+	free(pk);
+}
+
+static struct emv_pk *emv_pk_get_ca_pk_from_file(const char *fname,
+		const unsigned char *rid,
+		unsigned char idx)
+{
+	if  (!fname)
+		return NULL;
+
+	FILE *f = fopen(fname, "r");
+	if (!f) {
+		perror("fopen");
+		return NULL;
+	}
+
+	while (!feof(f)) {
+		char buf[BUFSIZ];
+		if (fgets(buf, sizeof(buf), f) == NULL)
+			break;
+
+		struct emv_pk *pk = emv_pk_parse_pk(buf);
+		if (!pk)
+			continue;
+		if (memcmp(pk->rid, rid, 5) || pk->index != idx) {
+			emv_pk_free(pk);
+			continue;
+		}
+
+		fclose(f);
+
+		return pk;
+	}
+
+	fclose(f);
+
+	return NULL;
+}
+
+char *emv_pk_get_ca_pk_file(const char *dirname, const unsigned char *rid, unsigned char idx)
+{
+	if (!dirname)
+		dirname = ".";//openemv_config_get_str("capk.dir", NULL);
+
+	if (!dirname)
+		return NULL;
+
+	char *filename;
+	int ret = asprintf(&filename, "%s/%02hhx%02hhx%02hhx%02hhx%02hhx_%02hhx.0",
+			dirname,
+			rid[0],
+			rid[1],
+			rid[2],
+			rid[3],
+			rid[4],
+			idx);
+
+	if (ret <= 0)
+		return NULL;
+
+	return filename;
+}
+
+char *emv_pk_get_ca_pk_rid_file(const char *dirname, const unsigned char *rid)
+{
+	if (!dirname)
+		dirname = "."; //openemv_config_get_str("capk.dir", NULL);
+
+	if (!dirname)
+		return NULL;
+
+	char *filename;
+	int ret = asprintf(&filename, "%s/%02hhx%02hhx%02hhx%02hhx%02hhx.pks",
+			dirname,
+			rid[0],
+			rid[1],
+			rid[2],
+			rid[3],
+			rid[4]);
+
+	if (ret <= 0)
+		return NULL;
+
+	return filename;
+}
+
+struct emv_pk *emv_pk_get_ca_pk(const unsigned char *rid, unsigned char idx)
+{
+	struct emv_pk *pk = NULL;
+
+	if (!pk) {
+		char *fname = emv_pk_get_ca_pk_file(NULL, rid, idx);
+		if (fname) {
+			pk = emv_pk_get_ca_pk_from_file(fname, rid, idx);
+			free(fname);
+		}
+	}
+
+	if (!pk) {
+		char *fname = emv_pk_get_ca_pk_rid_file(NULL, rid);
+		if (fname) {
+			pk = emv_pk_get_ca_pk_from_file(fname, rid, idx);
+			free(fname);
+		}
+	}
+
+	if (!pk) {
+		const char *fname = "capk.txt"; //openemv_config_get_str("capk.file", NULL);
+		if (!fname) {
+			fprintf(stderr, "No CA PK file specified!\n");
+			return NULL;
+		}
+
+		pk = emv_pk_get_ca_pk_from_file(fname, rid, idx);
+	}
+	if (!pk)
+		return NULL;
+
+	printf("Verifying CA PK for %02hhx:%02hhx:%02hhx:%02hhx:%02hhx IDX %02hhx %zd bits...",
+				pk->rid[0],
+				pk->rid[1],
+				pk->rid[2],
+				pk->rid[3],
+				pk->rid[4],
+				pk->index,
+				pk->mlen * 8);
+	if (emv_pk_verify(pk)) {
+		printf("OK\n");
+
+		return pk;
+	}
+
+	printf("Failed!\n");
+	emv_pk_free(pk);
+
+	return NULL;
+}
diff --git a/client/emv/emv_pk.h b/client/emv/emv_pk.h
new file mode 100644
index 00000000..e291a065
--- /dev/null
+++ b/client/emv/emv_pk.h
@@ -0,0 +1,48 @@
+/*
+ * libopenemv - a library to work with EMV family of smart cards
+ * Copyright (C) 2015 Dmitry Eremin-Solenikov
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ */
+
+#ifndef EMV_PK_H
+#define EMV_PK_H
+
+#include <stdbool.h>
+#include <stddef.h>
+
+struct emv_pk {
+	unsigned char rid[5];
+	unsigned char index;
+	unsigned char serial[3];
+	unsigned char pan[10];
+	unsigned char hash_algo;
+	unsigned char pk_algo;
+	unsigned char hash[20];
+	unsigned char exp[3];
+	size_t elen;
+	size_t mlen;
+	unsigned char *modulus;
+	unsigned int expire;
+};
+
+#define EXPIRE(yy, mm, dd)	0x ## yy ## mm ## dd
+
+struct emv_pk *emv_pk_parse_pk(char *buf);
+struct emv_pk *emv_pk_new(size_t modlen, size_t explen);
+void emv_pk_free(struct emv_pk *pk);
+char *emv_pk_dump_pk(const struct emv_pk *pk);
+bool emv_pk_verify(const struct emv_pk *pk);
+
+char *emv_pk_get_ca_pk_file(const char *dirname, const unsigned char *rid, unsigned char idx);
+char *emv_pk_get_ca_pk_rid_file(const char *dirname, const unsigned char *rid);
+struct emv_pk *emv_pk_get_ca_pk(const unsigned char *rid, unsigned char idx);
+#endif
diff --git a/client/emv/emv_pki.c b/client/emv/emv_pki.c
new file mode 100644
index 00000000..e4a9cc68
--- /dev/null
+++ b/client/emv/emv_pki.c
@@ -0,0 +1,390 @@
+/*
+ * libopenemv - a library to work with EMV family of smart cards
+ * Copyright (C) 2015 Dmitry Eremin-Solenikov
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "emv_pki.h"
+#include "crypto.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdarg.h>
+
+static const unsigned char empty_tlv_value[] = {};
+static const struct tlv empty_tlv = {.tag = 0x0, .len = 0, .value = empty_tlv_value};
+
+static size_t emv_pki_hash_psn[256] = { 0, 0, 11, 2, 17, 2, };
+
+static unsigned char *emv_pki_decode_message(const struct emv_pk *enc_pk,
+		uint8_t msgtype,
+		size_t *len,
+		const struct tlv *cert_tlv,
+		... /* A list of tlv pointers, end with NULL */
+		)
+{
+	struct crypto_pk *kcp;
+	unsigned char *data;
+	size_t data_len;
+	va_list vl;
+
+	if (!enc_pk)
+		return NULL;
+
+	if (!cert_tlv)
+		return NULL;
+
+	if (cert_tlv->len != enc_pk->mlen)
+		return NULL;
+
+	kcp = crypto_pk_open(enc_pk->pk_algo,
+			enc_pk->modulus, enc_pk->mlen,
+			enc_pk->exp, enc_pk->elen);
+	if (!kcp)
+		return NULL;
+
+	data = crypto_pk_encrypt(kcp, cert_tlv->value, cert_tlv->len, &data_len);
+	crypto_pk_close(kcp);
+
+	if (data[data_len-1] != 0xbc || data[0] != 0x6a || data[1] != msgtype) {
+		free(data);
+		return NULL;
+	}
+
+	size_t hash_pos = emv_pki_hash_psn[msgtype];
+	if (hash_pos == 0 || hash_pos > data_len){
+		free(data);
+		return NULL;
+	}
+
+	struct crypto_hash *ch;
+	ch = crypto_hash_open(data[hash_pos]);
+	if (!ch) {
+		free(data);
+		return NULL;
+	}
+
+	size_t hash_len = crypto_hash_get_size(ch);
+	crypto_hash_write(ch, data + 1, data_len - 2 - hash_len);
+
+	va_start(vl, cert_tlv);
+	while (true) {
+		const struct tlv *add_tlv = va_arg(vl, const struct tlv *);
+		if (!add_tlv)
+			break;
+
+		crypto_hash_write(ch, add_tlv->value, add_tlv->len);
+	}
+	va_end(vl);
+
+	if (memcmp(data + data_len - 1 - hash_len, crypto_hash_read(ch), hash_len)) {
+		crypto_hash_close(ch);
+		free(data);
+		return NULL;
+	}
+
+	crypto_hash_close(ch);
+
+	*len = data_len - hash_len - 1;
+
+	return data;
+}
+
+static unsigned emv_cn_length(const struct tlv *tlv)
+{
+	int i;
+
+	for (i = 0; i < tlv->len; i++) {
+		unsigned char c = tlv->value[i];
+
+		if (c >> 4 == 0xf)
+			return 2 * i;
+
+		if ((c & 0xf) == 0xf)
+			return 2 * i + 1;
+	}
+
+	return 2 * tlv->len;
+}
+
+static unsigned char emv_cn_get(const struct tlv *tlv, unsigned pos)
+{
+	if (pos > tlv->len * 2)
+		return 0xf;
+
+	unsigned char c = tlv->value[pos / 2];
+
+	if (pos % 2)
+		return c & 0xf;
+	else
+		return c >> 4;
+}
+
+static struct emv_pk *emv_pki_decode_key(const struct emv_pk *enc_pk,
+		unsigned char msgtype,
+		const struct tlv *pan_tlv,
+		const struct tlv *cert_tlv,
+		const struct tlv *exp_tlv,
+		const struct tlv *rem_tlv,
+		const struct tlv *add_tlv
+		)
+{
+	size_t pan_length;
+	unsigned char *data;
+	size_t data_len;
+	size_t pk_len;
+
+	if (!cert_tlv || !exp_tlv || !pan_tlv)
+		return NULL;
+
+	if (!rem_tlv)
+		rem_tlv = &empty_tlv;
+
+	if (msgtype == 2)
+		pan_length = 4;
+	else if (msgtype == 4)
+		pan_length = 10;
+	else
+		return NULL;
+
+	data = emv_pki_decode_message(enc_pk, msgtype, &data_len,
+			cert_tlv,
+			rem_tlv,
+			exp_tlv,
+			add_tlv,
+			NULL);
+	if (!data || data_len < 11 + pan_length)
+		return NULL;
+
+	/* Perform the rest of checks here */
+
+	struct tlv pan2_tlv = {
+		.tag = 0x5a,
+		.len = pan_length,
+		.value = &data[2],
+	};
+	unsigned pan_len = emv_cn_length(pan_tlv);
+	unsigned pan2_len = emv_cn_length(&pan2_tlv);
+
+	if (((msgtype == 2) && (pan2_len < 4 || pan2_len > pan_len)) ||
+	    ((msgtype == 4) && (pan2_len != pan_len))) {
+		free(data);
+
+		return NULL;
+	}
+
+	unsigned i;
+	for (i = 0; i < pan2_len; i++)
+		if (emv_cn_get(pan_tlv, i) != emv_cn_get(&pan2_tlv, i)) {
+			free(data);
+
+			return NULL;
+		}
+
+	pk_len = data[9 + pan_length];
+	if (pk_len > data_len - 11 - pan_length + rem_tlv->len) {
+		free(data);
+		return NULL;
+	}
+
+	if (exp_tlv->len != data[10 + pan_length]) {
+		free(data);
+		return NULL;
+	}
+
+	struct emv_pk *pk = emv_pk_new(pk_len, exp_tlv->len);
+
+	memcpy(pk->rid, enc_pk->rid, 5);
+	pk->index = enc_pk->index;
+
+	pk->hash_algo = data[7 + pan_length];
+	pk->pk_algo = data[8 + pan_length];
+	pk->expire = (data[3 + pan_length] << 16) | (data[2 + pan_length] << 8) | 0x31;
+	memcpy(pk->serial, data + 4 + pan_length, 3);
+	memcpy(pk->pan, data + 2, pan_length);
+	memset(pk->pan + pan_length, 0xff, 10 - pan_length);
+
+	memcpy(pk->modulus, data + 11 + pan_length,
+			pk_len < data_len - (11 + pan_length) ?
+			pk_len :
+			data_len - (11 + pan_length));
+	memcpy(pk->modulus + data_len - (11 + pan_length), rem_tlv->value, rem_tlv->len);
+	memcpy(pk->exp, exp_tlv->value, exp_tlv->len);
+
+	free(data);
+
+	return pk;
+}
+
+struct emv_pk *emv_pki_recover_issuer_cert(const struct emv_pk *pk, struct tlvdb *db)
+{
+	return emv_pki_decode_key(pk, 2,
+			tlvdb_get(db, 0x5a, NULL),
+			tlvdb_get(db, 0x90, NULL),
+			tlvdb_get(db, 0x9f32, NULL),
+			tlvdb_get(db, 0x92, NULL),
+			NULL);
+}
+
+struct emv_pk *emv_pki_recover_icc_cert(const struct emv_pk *pk, struct tlvdb *db, const struct tlv *sda_tlv)
+{
+	return emv_pki_decode_key(pk, 4,
+			tlvdb_get(db, 0x5a, NULL),
+			tlvdb_get(db, 0x9f46, NULL),
+			tlvdb_get(db, 0x9f47, NULL),
+			tlvdb_get(db, 0x9f48, NULL),
+			sda_tlv);
+}
+
+struct emv_pk *emv_pki_recover_icc_pe_cert(const struct emv_pk *pk, struct tlvdb *db)
+{
+	return emv_pki_decode_key(pk, 4,
+			tlvdb_get(db, 0x5a, NULL),
+			tlvdb_get(db, 0x9f2d, NULL),
+			tlvdb_get(db, 0x9f2e, NULL),
+			tlvdb_get(db, 0x9f2f, NULL),
+			NULL);
+}
+
+struct tlvdb *emv_pki_recover_dac(const struct emv_pk *enc_pk, const struct tlvdb *db, const struct tlv *sda_tlv)
+{
+	size_t data_len;
+	unsigned char *data = emv_pki_decode_message(enc_pk, 3, &data_len,
+			tlvdb_get(db, 0x93, NULL),
+			sda_tlv,
+			NULL);
+
+	if (!data || data_len < 5)
+		return NULL;
+
+	struct tlvdb *dac_db = tlvdb_fixed(0x9f45, 2, data+3);
+
+	free(data);
+
+	return dac_db;
+}
+
+struct tlvdb *emv_pki_recover_idn(const struct emv_pk *enc_pk, const struct tlvdb *db, const struct tlv *dyn_tlv)
+{
+	size_t data_len;
+	unsigned char *data = emv_pki_decode_message(enc_pk, 5, &data_len,
+			tlvdb_get(db, 0x9f4b, NULL),
+			dyn_tlv,
+			NULL);
+
+	if (!data || data_len < 3)
+		return NULL;
+
+	if (data[3] < 2 || data[3] > data_len - 3) {
+		free(data);
+		return NULL;
+	}
+
+	size_t idn_len = data[4];
+	if (idn_len > data[3] - 1) {
+		free(data);
+		return NULL;
+	}
+
+	struct tlvdb *idn_db = tlvdb_fixed(0x9f4c, idn_len, data + 5);
+	free(data);
+
+	return idn_db;
+}
+
+static bool tlv_hash(void *data, const struct tlv *tlv, int level, bool is_leaf)
+{
+	struct crypto_hash *ch = data;
+	size_t tag_len;
+	unsigned char *tag;
+
+	if (tlv_is_constructed(tlv))
+		return true;
+
+	if (tlv->tag == 0x9f4b)
+		return true;
+
+	tag = tlv_encode(tlv, &tag_len);
+	crypto_hash_write(ch, tag, tag_len);
+	free(tag);
+
+	return true;
+}
+
+struct tlvdb *emv_pki_perform_cda(const struct emv_pk *enc_pk, const struct tlvdb *db,
+		const struct tlvdb *this_db,
+		const struct tlv *pdol_data_tlv,
+		const struct tlv *crm1_tlv,
+		const struct tlv *crm2_tlv)
+{
+	const struct tlv *un_tlv = tlvdb_get(db, 0x9f37, NULL);
+	const struct tlv *cid_tlv = tlvdb_get(this_db, 0x9f27, NULL);
+
+	if (!un_tlv || !cid_tlv)
+		return NULL;
+
+	size_t data_len;
+	unsigned char *data = emv_pki_decode_message(enc_pk, 5, &data_len,
+			tlvdb_get(this_db, 0x9f4b, NULL),
+			un_tlv,
+			NULL);
+	if (!data || data_len < 3)
+		return NULL;
+
+	if (data[3] < 30 || data[3] > data_len - 4) {
+		free(data);
+		return NULL;
+	}
+
+	if (!cid_tlv || cid_tlv->len != 1 || cid_tlv->value[0] != data[5 + data[4]]) {
+		free(data);
+		return NULL;
+	}
+
+	struct crypto_hash *ch;
+	ch = crypto_hash_open(enc_pk->hash_algo);
+	if (!ch) {
+		free(data);
+		return NULL;
+	}
+
+	if (pdol_data_tlv)
+		crypto_hash_write(ch, pdol_data_tlv->value, pdol_data_tlv->len);
+	if (crm1_tlv)
+		crypto_hash_write(ch, crm1_tlv->value, crm1_tlv->len);
+	if (crm2_tlv)
+		crypto_hash_write(ch, crm2_tlv->value, crm2_tlv->len);
+
+	tlvdb_visit(this_db, tlv_hash, ch, 0);
+
+	if (memcmp(data + 5 + data[4] + 1 + 8, crypto_hash_read(ch), 20)) {
+		crypto_hash_close(ch);
+		free(data);
+		return NULL;
+	}
+	crypto_hash_close(ch);
+
+	size_t idn_len = data[4];
+	if (idn_len > data[3] - 1) {
+		free(data);
+		return NULL;
+	}
+
+	struct tlvdb *idn_db = tlvdb_fixed(0x9f4c, idn_len, data + 5);
+	free(data);
+
+	return idn_db;
+}
diff --git a/client/emv/emv_pki.h b/client/emv/emv_pki.h
new file mode 100644
index 00000000..72d84cc4
--- /dev/null
+++ b/client/emv/emv_pki.h
@@ -0,0 +1,36 @@
+/*
+ * libopenemv - a library to work with EMV family of smart cards
+ * Copyright (C) 2015 Dmitry Eremin-Solenikov
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ */
+
+#ifndef EMV_PKI_H
+#define EMV_PKI_H
+
+#include "emv_pk.h"
+#include "tlv.h"
+
+#include <stddef.h>
+
+struct emv_pk *emv_pki_recover_issuer_cert(const struct emv_pk *pk, struct tlvdb *db);
+struct emv_pk *emv_pki_recover_icc_cert(const struct emv_pk *pk, struct tlvdb *db, const struct tlv *sda_tlv);
+struct emv_pk *emv_pki_recover_icc_pe_cert(const struct emv_pk *pk, struct tlvdb *db);
+
+struct tlvdb *emv_pki_recover_dac(const struct emv_pk *pk, const struct tlvdb *db, const struct tlv *sda_tlv);
+struct tlvdb *emv_pki_recover_idn(const struct emv_pk *pk, const struct tlvdb *db, const struct tlv *dyn_tlv);
+struct tlvdb *emv_pki_perform_cda(const struct emv_pk *enc_pk, const struct tlvdb *db,
+		const struct tlvdb *this_db,
+		const struct tlv *pdol_data_tlv,
+		const struct tlv *crm1_tlv,
+		const struct tlv *crm2_tlv);
+
+#endif
diff --git a/client/emv/emv_pki_priv.c b/client/emv/emv_pki_priv.c
new file mode 100644
index 00000000..a7043a77
--- /dev/null
+++ b/client/emv/emv_pki_priv.c
@@ -0,0 +1,281 @@
+/*
+ * libopenemv - a library to work with EMV family of smart cards
+ * Copyright (C) 2015 Dmitry Eremin-Solenikov
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "emv_pki_priv.h"
+#include "crypto.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdarg.h>
+
+struct emv_pk *emv_pki_make_ca(const struct crypto_pk *cp,
+		const unsigned char *rid, unsigned char index,
+		unsigned int expire, enum crypto_algo_hash hash_algo)
+{
+	size_t modlen, explen;
+	unsigned char *mod, *exp;
+
+	if (!rid)
+		return NULL;
+
+	mod = crypto_pk_get_parameter(cp, 0, &modlen);
+	exp = crypto_pk_get_parameter(cp, 1, &explen);
+
+	if (!mod || !modlen || !exp || !explen) {
+		free(mod);
+		free(exp);
+
+		return NULL;
+	}
+
+	struct emv_pk *pk = emv_pk_new(modlen, explen);
+	memcpy(pk->rid, rid, 5);
+	pk->index = index;
+	pk->expire = expire;
+	pk->pk_algo = crypto_pk_get_algo(cp);
+	pk->hash_algo = hash_algo;
+	memcpy(pk->modulus, mod, modlen);
+	memcpy(pk->exp, exp, explen);
+
+	free(mod);
+	free(exp);
+
+	struct crypto_hash *ch = crypto_hash_open(pk->hash_algo);
+	if (!ch)
+		return false;
+
+	crypto_hash_write(ch, pk->rid, sizeof(pk->rid));
+	crypto_hash_write(ch, &pk->index, 1);
+	crypto_hash_write(ch, pk->modulus, pk->mlen);
+	crypto_hash_write(ch, pk->exp, pk->elen);
+
+	unsigned char *h = crypto_hash_read(ch);
+	if (!h) {
+		crypto_hash_close(ch);
+		emv_pk_free(pk);
+
+		return NULL;
+	}
+
+	memcpy(pk->hash, h, crypto_hash_get_size(ch));
+	crypto_hash_close(ch);
+
+	return pk;
+}
+
+static struct tlvdb *emv_pki_sign_message(const struct crypto_pk *cp,
+		tlv_tag_t cert_tag, tlv_tag_t rem_tag,
+		const unsigned char *msg, size_t msg_len,
+		... /* A list of tlv pointers, end with NULL */
+		)
+{
+	size_t tmp_len = (crypto_pk_get_nbits(cp) + 7) / 8;
+	unsigned char *tmp = malloc(tmp_len);
+	if (!tmp)
+		return NULL;
+
+	// XXX
+	struct crypto_hash *ch = crypto_hash_open(HASH_SHA_1);
+	if (!ch) {
+		free(tmp);
+
+		return NULL;
+	}
+
+	tmp[0] = 0x6a;
+	tmp[tmp_len - 1] = 0xbc;
+
+	const unsigned char *rem;
+	size_t rem_len;
+	size_t hash_len = crypto_hash_get_size(ch);
+	size_t part_len = tmp_len - 2 - hash_len;
+	if (part_len < msg_len) {
+		memcpy(tmp + 1, msg, part_len);
+		rem = msg + part_len;
+		rem_len = msg_len - part_len;
+	} else {
+		memcpy(tmp + 1, msg, msg_len);
+		memset(tmp + 1 + msg_len, 0xbb, part_len - msg_len);
+		rem = NULL;
+		rem_len = 0;
+	}
+	crypto_hash_write(ch, tmp + 1, part_len);
+	crypto_hash_write(ch, rem, rem_len);
+
+	va_list vl;
+	va_start(vl, msg_len);
+	while (true) {
+		const struct tlv *add_tlv = va_arg(vl, const struct tlv *);
+		if (!add_tlv)
+			break;
+
+		crypto_hash_write(ch, add_tlv->value, add_tlv->len);
+	}
+	va_end(vl);
+
+	unsigned char *h = crypto_hash_read(ch);
+	if (!h) {
+		crypto_hash_close(ch);
+		free(tmp);
+
+		return NULL;
+	}
+
+	memcpy(tmp + 1 + part_len, h, hash_len);
+	crypto_hash_close(ch);
+
+	size_t cert_len;
+	unsigned char *cert = crypto_pk_decrypt(cp, tmp, tmp_len, &cert_len);
+	free(tmp);
+
+	if (!cert)
+		return NULL;
+
+	struct tlvdb *db = tlvdb_fixed(cert_tag, cert_len, cert);
+	free(cert);
+	if (!db)
+		return NULL;
+
+	if (rem) {
+		struct tlvdb *rdb = tlvdb_fixed(rem_tag, rem_len, rem);
+		if (!rdb) {
+			tlvdb_free(db);
+
+			return NULL;
+		}
+		tlvdb_add(db, rdb);
+	}
+
+	return db;
+}
+
+static struct tlvdb *emv_pki_sign_key(const struct crypto_pk *cp,
+		struct emv_pk *ipk,
+		unsigned char msgtype,
+		size_t pan_len,
+		tlv_tag_t cert_tag,
+		tlv_tag_t exp_tag,
+		tlv_tag_t rem_tag,
+		const struct tlv *add_tlv
+		)
+{
+	unsigned pos = 0;
+	unsigned char *msg = malloc(1 + pan_len + 2 + 3 + 1 + 1 + 1 + 1 + ipk->mlen);
+
+	if (!msg)
+		return NULL;
+
+	msg[pos++] = msgtype;
+	memcpy(msg + pos, ipk->pan, pan_len); pos += pan_len;
+	msg[pos++] = (ipk->expire >> 8) & 0xff;
+	msg[pos++] = (ipk->expire >> 16) & 0xff;
+	memcpy(msg + pos, ipk->serial, 3); pos += 3;
+	msg[pos++] = ipk->hash_algo;
+	msg[pos++] = ipk->pk_algo;
+	msg[pos++] = ipk->mlen;
+	msg[pos++] = ipk->elen;
+	memcpy(msg + pos, ipk->modulus, ipk->mlen);
+	pos += ipk->mlen;
+
+	struct tlvdb *exp_db = tlvdb_fixed(exp_tag, ipk->elen, ipk->exp);
+	if (!exp_db) {
+		free(msg);
+
+		return NULL;
+	}
+
+	struct tlvdb *db = emv_pki_sign_message(cp,
+			cert_tag, rem_tag,
+			msg, pos,
+			tlvdb_get(exp_db, exp_tag, NULL),
+			add_tlv,
+			NULL);
+	free(msg);
+	if (!db)
+		return NULL;
+
+	tlvdb_add(db, exp_db);
+
+	return db;
+}
+
+struct tlvdb *emv_pki_sign_issuer_cert(const struct crypto_pk *cp, struct emv_pk *issuer_pk)
+{
+	return emv_pki_sign_key(cp, issuer_pk, 2, 4, 0x90, 0x9f32, 0x92, NULL);
+}
+
+struct tlvdb *emv_pki_sign_icc_cert(const struct crypto_pk *cp, struct emv_pk *icc_pk, const struct tlv *sda_tlv)
+{
+	return emv_pki_sign_key(cp, icc_pk, 4, 10, 0x9f46, 0x9f47, 0x9f48, sda_tlv);
+}
+
+struct tlvdb *emv_pki_sign_icc_pe_cert(const struct crypto_pk *cp, struct emv_pk *icc_pe_pk)
+{
+	return emv_pki_sign_key(cp, icc_pe_pk, 4, 10, 0x9f2d, 0x9f2e, 0x9f2f, NULL);
+}
+
+struct tlvdb *emv_pki_sign_dac(const struct crypto_pk *cp, const struct tlv *dac_tlv, const struct tlv *sda_tlv)
+{
+	unsigned pos = 0;
+	unsigned char *msg = malloc(1+1+dac_tlv->len);
+
+	if (!msg)
+		return NULL;
+
+	msg[pos++] = 3;
+	msg[pos++] = HASH_SHA_1;
+	memcpy(msg+pos, dac_tlv->value, dac_tlv->len);
+	pos += dac_tlv->len;
+
+	struct tlvdb *db = emv_pki_sign_message(cp,
+			0x93, 0,
+			msg, pos,
+			sda_tlv,
+			NULL);
+
+	free(msg);
+
+	return db;
+}
+
+struct tlvdb *emv_pki_sign_idn(const struct crypto_pk *cp, const struct tlv *idn_tlv, const struct tlv *dyn_tlv)
+{
+	unsigned pos = 0;
+	unsigned char *msg = malloc(1+1+1+1+idn_tlv->len);
+
+	if (!msg)
+		return NULL;
+
+	msg[pos++] = 5;
+	msg[pos++] = HASH_SHA_1;
+	msg[pos++] = idn_tlv->len + 1;
+	msg[pos++] = idn_tlv->len;
+	memcpy(msg+pos, idn_tlv->value, idn_tlv->len);
+	pos += idn_tlv->len;
+
+	struct tlvdb *db = emv_pki_sign_message(cp,
+			0x9f4b, 0,
+			msg, pos,
+			dyn_tlv,
+			NULL);
+
+	free(msg);
+
+	return db;
+}
diff --git a/client/emv/emv_pki_priv.h b/client/emv/emv_pki_priv.h
new file mode 100644
index 00000000..4f1639d5
--- /dev/null
+++ b/client/emv/emv_pki_priv.h
@@ -0,0 +1,35 @@
+/*
+ * libopenemv - a library to work with EMV family of smart cards
+ * Copyright (C) 2015 Dmitry Eremin-Solenikov
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ */
+
+#ifndef EMV_PKI_PRIV_H
+#define EMV_PKI_PRIV_H
+
+#include "crypto.h"
+#include "emv_pk.h"
+#include "tlv.h"
+
+#include <stddef.h>
+
+struct emv_pk *emv_pki_make_ca(const struct crypto_pk *cp,
+		const unsigned char *rid, unsigned char index,
+		unsigned int expire, enum crypto_algo_hash hash_algo);
+struct tlvdb *emv_pki_sign_issuer_cert(const struct crypto_pk *cp, struct emv_pk *issuer_pk);
+struct tlvdb *emv_pki_sign_icc_cert(const struct crypto_pk *cp, struct emv_pk *icc_pk, const struct tlv *sda_tlv);
+struct tlvdb *emv_pki_sign_icc_pe_cert(const struct crypto_pk *cp, struct emv_pk *icc_pe_pk);
+
+struct tlvdb *emv_pki_sign_dac(const struct crypto_pk *cp, const struct tlv *dac_tlv, const struct tlv *sda_tlv);
+struct tlvdb *emv_pki_sign_idn(const struct crypto_pk *cp, const struct tlv *idn_tlv, const struct tlv *dyn_tlv);
+
+#endif