X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/69f98ec91e3fac3155d8e577c7544f7c99cec447..d03fb293bce1b06d49fb9faf5c492a1e2effc24b:/client/emv/emv_pk.c

diff --git a/client/emv/emv_pk.c b/client/emv/emv_pk.c
new file mode 100644
index 00000000..b577855e
--- /dev/null
+++ b/client/emv/emv_pk.c
@@ -0,0 +1,524 @@
+/*
+ * 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
+
+/* For asprintf */
+#define _GNU_SOURCE
+#include <stdio.h>
+
+#include "emv_pk.h"
+#include "crypto.h"
+#include "proxmark3.h"
+
+#include <stdbool.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/types.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[2048];
+		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 *relfname = "emv/capk.txt"; 
+
+		char fname[strlen(get_my_executable_directory()) + strlen(relfname) + 1];
+		strcpy(fname, get_my_executable_directory());
+		strcat(fname, relfname);
+
+		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;
+}