- rees@cvs.openbsd.org 2002/03/21 21:54:34
[scard.c scard.h ssh-keygen.c]
Add PIN-protection for secret key.
diff --git a/scard.c b/scard.c
index 9d044ac..a8ee2fe 100644
--- a/scard.c
+++ b/scard.c
@@ -24,7 +24,7 @@
#include "includes.h"
#ifdef SMARTCARD
-RCSID("$OpenBSD: scard.c,v 1.21 2002/03/21 18:08:15 rees Exp $");
+RCSID("$OpenBSD: scard.c,v 1.22 2002/03/21 21:54:34 rees Exp $");
#include <openssl/engine.h>
#include <openssl/evp.h>
@@ -33,8 +33,8 @@
#include "key.h"
#include "log.h"
#include "xmalloc.h"
-#include "scard.h"
#include "readpass.h"
+#include "scard.h"
#ifdef OPENSSL_VERSION_NUMBER
#if OPENSSL_VERSION_NUMBER >= 0x00907000L
@@ -53,10 +53,16 @@
#define MAX_BUF_SIZE 256
+u_char DEFAUT0[] = {0xad, 0x9f, 0x61, 0xfe, 0xfa, 0x20, 0xce, 0x63};
+
static int sc_fd = -1;
static char *sc_reader_id = NULL;
+static char *sc_pin = NULL;
static int cla = 0x00; /* class */
+static void sc_mk_digest(const char *pin, u_char *digest);
+static int get_AUT0(u_char *aut0);
+
/* interface to libsectok */
static int
@@ -193,6 +199,7 @@
int padding)
{
u_char *padded = NULL;
+ u_char aut0[EVP_MAX_MD_SIZE];
int sw, len, olen, status = -1;
debug("sc_private_decrypt called");
@@ -209,20 +216,34 @@
len = BN_num_bytes(rsa->n);
padded = xmalloc(len);
- sectok_apdu(sc_fd, CLA_SSH, INS_DECRYPT, 0, 0, len, (u_char *)from,
- 0, NULL, &sw);
+ sectok_apdu(sc_fd, CLA_SSH, INS_DECRYPT, 0, 0, len, from, len, padded, &sw);
+
+ if (sw == 0x6982) {
+ /* permission denied; try PIN if provided */
+ if (sc_pin && strlen(sc_pin) > 0) {
+ sc_mk_digest(sc_pin, aut0);
+ if (cyberflex_verify_AUT0(sc_fd, cla, aut0, 8) < 0) {
+ error("smartcard passphrase incorrect");
+ goto err;
+ }
+ } else {
+ /* try default AUT0 key */
+ if (cyberflex_verify_AUT0(sc_fd, cla, DEFAUT0, 8) < 0) {
+ /* default AUT0 key failed; prompt for passphrase */
+ if (get_AUT0(aut0) < 0 ||
+ cyberflex_verify_AUT0(sc_fd, cla, aut0, 8) < 0) {
+ error("smartcard passphrase incorrect");
+ goto err;
+ }
+ }
+ }
+ sectok_apdu(sc_fd, CLA_SSH, INS_DECRYPT, 0, 0, len, from, len, padded, &sw);
+ }
if (!sectok_swOK(sw)) {
error("sc_private_decrypt: INS_DECRYPT failed: %s",
sectok_get_sw(sw));
goto err;
}
- sectok_apdu(sc_fd, CLA_SSH, INS_GET_RESPONSE, 0, 0, 0, NULL,
- len, padded, &sw);
- if (!sectok_swOK(sw)) {
- error("sc_private_decrypt: INS_GET_RESPONSE failed: %s",
- sectok_get_sw(sw));
- goto err;
- }
olen = RSA_padding_check_PKCS1_type_2(to, len, padded + 1, len - 1,
len);
err:
@@ -256,19 +277,12 @@
error("RSA_padding_add_PKCS1_type_1 failed");
goto err;
}
- sectok_apdu(sc_fd, CLA_SSH, INS_DECRYPT, 0, 0, len, padded, 0, NULL, &sw);
+ sectok_apdu(sc_fd, CLA_SSH, INS_DECRYPT, 0, 0, len, padded, len, to, &sw);
if (!sectok_swOK(sw)) {
error("sc_private_decrypt: INS_DECRYPT failed: %s",
sectok_get_sw(sw));
goto err;
}
- sectok_apdu(sc_fd, CLA_SSH, INS_GET_RESPONSE, 0, 0, 0, NULL,
- len, to, &sw);
- if (!sectok_swOK(sw)) {
- error("sc_private_decrypt: INS_GET_RESPONSE failed: %s",
- sectok_get_sw(sw));
- goto err;
- }
err:
if (padded)
xfree(padded);
@@ -340,7 +354,7 @@
}
Key *
-sc_get_key(const char *id)
+sc_get_key(const char *id, const char *pin)
{
Key *k;
int status;
@@ -349,6 +363,10 @@
xfree(sc_reader_id);
sc_reader_id = xstrdup(id);
+ if (sc_pin != NULL)
+ xfree(sc_pin);
+ sc_pin = (pin == NULL) ? NULL : xstrdup(pin);
+
k = key_new(KEY_RSA);
if (k == NULL) {
return NULL;
@@ -376,19 +394,30 @@
goto done; \
} while (0)
-static int
-get_AUT0(char *aut0)
+static void
+sc_mk_digest(const char *pin, u_char *digest)
{
const EVP_MD *evp_md = EVP_sha1();
EVP_MD_CTX md;
+
+ EVP_DigestInit(&md, evp_md);
+ EVP_DigestUpdate(&md, pin, strlen(pin));
+ EVP_DigestFinal(&md, digest, NULL);
+}
+
+static int
+get_AUT0(u_char *aut0)
+{
char *pass;
pass = read_passphrase("Enter passphrase for smartcard: ", RP_ALLOW_STDIN);
if (pass == NULL)
return -1;
- EVP_DigestInit(&md, evp_md);
- EVP_DigestUpdate(&md, pass, strlen(pass));
- EVP_DigestFinal(&md, aut0, NULL);
+ if (!strcmp(pass, "-")) {
+ memcpy(aut0, DEFAUT0, sizeof DEFAUT0);
+ return 0;
+ }
+ sc_mk_digest(pass, aut0);
memset(pass, 0, strlen(pass));
xfree(pass);
return 0;
@@ -399,7 +428,6 @@
{
u_char *elements[NUM_RSA_KEY_ELEMENTS];
u_char key_fid[2];
- u_char DEFAUT0[] = {0xad, 0x9f, 0x61, 0xfe, 0xfa, 0x20, 0xce, 0x63};
u_char AUT0[EVP_MAX_MD_SIZE];
int len, status = -1, i, fd = -1, ret;
int sw = 0, cla = 0x00;
@@ -436,10 +464,12 @@
if (cyberflex_verify_AUT0(fd, cla, AUT0, sizeof(DEFAUT0)) < 0) {
if (get_AUT0(AUT0) < 0 ||
cyberflex_verify_AUT0(fd, cla, AUT0, sizeof(DEFAUT0)) < 0) {
- error("cyberflex_verify_AUT0 failed");
+ memset(AUT0, 0, sizeof(DEFAUT0));
+ error("smartcard passphrase incorrect");
goto done;
}
}
+ memset(AUT0, 0, sizeof(DEFAUT0));
key_fid[0] = 0x00;
key_fid[1] = 0x12;
if (cyberflex_load_rsa_priv(fd, cla, key_fid, 5, 8*len, elements,