diff options
Diffstat (limited to 'crypto/openssh/scard-opensc.c')
-rw-r--r-- | crypto/openssh/scard-opensc.c | 462 |
1 files changed, 462 insertions, 0 deletions
diff --git a/crypto/openssh/scard-opensc.c b/crypto/openssh/scard-opensc.c new file mode 100644 index 0000000..dd21de3 --- /dev/null +++ b/crypto/openssh/scard-opensc.c @@ -0,0 +1,462 @@ +/* + * Copyright (c) 2002 Juha Yrjölä. All rights reserved. + * Copyright (c) 2001 Markus Friedl. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include "includes.h" +#if defined(SMARTCARD) && defined(USE_OPENSC) + +#include <openssl/evp.h> +#include <openssl/x509.h> + +#include <opensc/opensc.h> +#include <opensc/pkcs15.h> + +#include "key.h" +#include "log.h" +#include "xmalloc.h" +#include "readpass.h" +#include "scard.h" + +#if OPENSSL_VERSION_NUMBER < 0x00907000L && defined(CRYPTO_LOCK_ENGINE) +#define USE_ENGINE +#define RSA_get_default_method RSA_get_default_openssl_method +#else +#endif + +#ifdef USE_ENGINE +#include <openssl/engine.h> +#define sc_get_rsa sc_get_engine +#else +#define sc_get_rsa sc_get_rsa_method +#endif + +static int sc_reader_id; +static sc_context_t *ctx = NULL; +static sc_card_t *card = NULL; +static sc_pkcs15_card_t *p15card = NULL; + +static char *sc_pin = NULL; + +struct sc_priv_data +{ + struct sc_pkcs15_id cert_id; + int ref_count; +}; + +void +sc_close(void) +{ + if (p15card) { + sc_pkcs15_unbind(p15card); + p15card = NULL; + } + if (card) { + sc_disconnect_card(card, 0); + card = NULL; + } + if (ctx) { + sc_release_context(ctx); + ctx = NULL; + } +} + +static int +sc_init(void) +{ + int r; + + r = sc_establish_context(&ctx, "openssh"); + if (r) + goto err; + r = sc_connect_card(ctx->reader[sc_reader_id], 0, &card); + if (r) + goto err; + r = sc_pkcs15_bind(card, &p15card); + if (r) + goto err; + return 0; +err: + sc_close(); + return r; +} + +/* private key operations */ + +static int +sc_prkey_op_init(RSA *rsa, struct sc_pkcs15_object **key_obj_out) +{ + int r; + struct sc_priv_data *priv; + struct sc_pkcs15_object *key_obj; + struct sc_pkcs15_prkey_info *key; + struct sc_pkcs15_object *pin_obj; + struct sc_pkcs15_pin_info *pin; + + priv = (struct sc_priv_data *) RSA_get_app_data(rsa); + if (priv == NULL) + return -1; + if (p15card == NULL) { + sc_close(); + r = sc_init(); + if (r) { + error("SmartCard init failed: %s", sc_strerror(r)); + goto err; + } + } + r = sc_pkcs15_find_prkey_by_id(p15card, &priv->cert_id, &key_obj); + if (r) { + error("Unable to find private key from SmartCard: %s", + sc_strerror(r)); + goto err; + } + key = key_obj->data; + r = sc_pkcs15_find_pin_by_auth_id(p15card, &key_obj->auth_id, + &pin_obj); + if (r) { + error("Unable to find PIN object from SmartCard: %s", + sc_strerror(r)); + goto err; + } + pin = pin_obj->data; + r = sc_lock(card); + if (r) { + error("Unable to lock smartcard: %s", sc_strerror(r)); + goto err; + } + if (sc_pin != NULL) { + r = sc_pkcs15_verify_pin(p15card, pin, sc_pin, + strlen(sc_pin)); + if (r) { + sc_unlock(card); + error("PIN code verification failed: %s", + sc_strerror(r)); + goto err; + } + } + *key_obj_out = key_obj; + return 0; +err: + sc_close(); + return -1; +} + +static int +sc_private_decrypt(int flen, u_char *from, u_char *to, RSA *rsa, + int padding) +{ + struct sc_pkcs15_object *key_obj; + int r; + + if (padding != RSA_PKCS1_PADDING) + return -1; + r = sc_prkey_op_init(rsa, &key_obj); + if (r) + return -1; + r = sc_pkcs15_decipher(p15card, key_obj, 0, from, flen, to, flen); + sc_unlock(card); + if (r < 0) { + error("sc_pkcs15_decipher() failed: %s", sc_strerror(r)); + goto err; + } + return r; +err: + sc_close(); + return -1; +} + +static int +sc_sign(int type, u_char *m, unsigned int m_len, + unsigned char *sigret, unsigned int *siglen, RSA *rsa) +{ + struct sc_pkcs15_object *key_obj; + int r; + unsigned long flags = 0; + + r = sc_prkey_op_init(rsa, &key_obj); + if (r) + return -1; + /* FIXME: length of sigret correct? */ + /* FIXME: check 'type' and modify flags accordingly */ + flags = SC_ALGORITHM_RSA_PAD_PKCS1 | SC_ALGORITHM_RSA_HASH_SHA1; + r = sc_pkcs15_compute_signature(p15card, key_obj, flags, + m, m_len, sigret, RSA_size(rsa)); + sc_unlock(card); + if (r < 0) { + error("sc_pkcs15_compute_signature() failed: %s", + sc_strerror(r)); + goto err; + } + *siglen = r; + return 1; +err: + sc_close(); + return 0; +} + +static int +sc_private_encrypt(int flen, u_char *from, u_char *to, RSA *rsa, + int padding) +{ + error("Private key encryption not supported"); + return -1; +} + +/* called on free */ + +static int (*orig_finish)(RSA *rsa) = NULL; + +static int +sc_finish(RSA *rsa) +{ + struct sc_priv_data *priv; + + priv = RSA_get_app_data(rsa); + priv->ref_count--; + if (priv->ref_count == 0) { + free(priv); + sc_close(); + } + if (orig_finish) + orig_finish(rsa); + return 1; +} + +/* engine for overloading private key operations */ + +static RSA_METHOD * +sc_get_rsa_method(void) +{ + static RSA_METHOD smart_rsa; + const RSA_METHOD *def = RSA_get_default_method(); + + /* use the OpenSSL version */ + memcpy(&smart_rsa, def, sizeof(smart_rsa)); + + smart_rsa.name = "opensc"; + + /* overload */ + smart_rsa.rsa_priv_enc = sc_private_encrypt; + smart_rsa.rsa_priv_dec = sc_private_decrypt; + smart_rsa.rsa_sign = sc_sign; + + /* save original */ + orig_finish = def->finish; + smart_rsa.finish = sc_finish; + + return &smart_rsa; +} + +#ifdef USE_ENGINE +static ENGINE * +sc_get_engine(void) +{ + static ENGINE *smart_engine = NULL; + + if ((smart_engine = ENGINE_new()) == NULL) + fatal("ENGINE_new failed"); + + ENGINE_set_id(smart_engine, "opensc"); + ENGINE_set_name(smart_engine, "OpenSC"); + + ENGINE_set_RSA(smart_engine, sc_get_rsa_method()); + ENGINE_set_DSA(smart_engine, DSA_get_default_openssl_method()); + ENGINE_set_DH(smart_engine, DH_get_default_openssl_method()); + ENGINE_set_RAND(smart_engine, RAND_SSLeay()); + ENGINE_set_BN_mod_exp(smart_engine, BN_mod_exp); + + return smart_engine; +} +#endif + +static void +convert_rsa_to_rsa1(Key * in, Key * out) +{ + struct sc_priv_data *priv; + + out->rsa->flags = in->rsa->flags; + out->flags = in->flags; + RSA_set_method(out->rsa, RSA_get_method(in->rsa)); + BN_copy(out->rsa->n, in->rsa->n); + BN_copy(out->rsa->e, in->rsa->e); + priv = RSA_get_app_data(in->rsa); + priv->ref_count++; + RSA_set_app_data(out->rsa, priv); + return; +} + +static int +sc_read_pubkey(Key * k, const struct sc_pkcs15_object *cert_obj) +{ + int r; + sc_pkcs15_cert_t *cert = NULL; + struct sc_priv_data *priv = NULL; + sc_pkcs15_cert_info_t *cinfo = cert_obj->data; + + X509 *x509 = NULL; + EVP_PKEY *pubkey = NULL; + u8 *p; + char *tmp; + + debug("sc_read_pubkey() with cert id %02X", cinfo->id.value[0]); + r = sc_pkcs15_read_certificate(p15card, cinfo, &cert); + if (r) { + log("Certificate read failed: %s", sc_strerror(r)); + goto err; + } + x509 = X509_new(); + if (x509 == NULL) { + r = -1; + goto err; + } + p = cert->data; + if (!d2i_X509(&x509, &p, cert->data_len)) { + log("Unable to parse X.509 certificate"); + r = -1; + goto err; + } + sc_pkcs15_free_certificate(cert); + cert = NULL; + pubkey = X509_get_pubkey(x509); + X509_free(x509); + x509 = NULL; + if (pubkey->type != EVP_PKEY_RSA) { + log("Public key is of unknown type"); + r = -1; + goto err; + } + k->rsa = EVP_PKEY_get1_RSA(pubkey); + EVP_PKEY_free(pubkey); + + k->rsa->flags |= RSA_FLAG_SIGN_VER; + RSA_set_method(k->rsa, sc_get_rsa_method()); + priv = xmalloc(sizeof(struct sc_priv_data)); + priv->cert_id = cinfo->id; + priv->ref_count = 1; + RSA_set_app_data(k->rsa, priv); + + k->flags = KEY_FLAG_EXT; + tmp = key_fingerprint(k, SSH_FP_MD5, SSH_FP_HEX); + debug("fingerprint %d %s", key_size(k), tmp); + xfree(tmp); + + return 0; +err: + if (cert) + sc_pkcs15_free_certificate(cert); + if (pubkey) + EVP_PKEY_free(pubkey); + if (x509) + X509_free(x509); + return r; +} + +Key ** +sc_get_keys(const char *id, const char *pin) +{ + Key *k, **keys; + int i, r, real_count = 0, key_count; + sc_pkcs15_id_t cert_id; + sc_pkcs15_object_t *certs[32]; + char *buf = xstrdup(id), *p; + + debug("sc_get_keys called: id = %s", id); + + if (sc_pin != NULL) + xfree(sc_pin); + sc_pin = (pin == NULL) ? NULL : xstrdup(pin); + + cert_id.len = 0; + if ((p = strchr(buf, ':')) != NULL) { + *p = 0; + p++; + sc_pkcs15_hex_string_to_id(p, &cert_id); + } + r = sscanf(buf, "%d", &sc_reader_id); + xfree(buf); + if (r != 1) + goto err; + if (p15card == NULL) { + sc_close(); + r = sc_init(); + if (r) { + error("Smartcard init failed: %s", sc_strerror(r)); + goto err; + } + } + if (cert_id.len) { + r = sc_pkcs15_find_cert_by_id(p15card, &cert_id, &certs[0]); + if (r < 0) + goto err; + key_count = 1; + } else { + r = sc_pkcs15_get_objects(p15card, SC_PKCS15_TYPE_CERT_X509, + certs, 32); + if (r == 0) { + log("No certificates found on smartcard"); + r = -1; + goto err; + } else if (r < 0) { + error("Certificate enumeration failed: %s", + sc_strerror(r)); + goto err; + } + key_count = r; + } + /* FIXME: only keep entries with a corresponding private key */ + keys = xmalloc(sizeof(Key *) * (key_count*2+1)); + for (i = 0; i < key_count; i++) { + k = key_new(KEY_RSA); + if (k == NULL) + break; + r = sc_read_pubkey(k, certs[i]); + if (r) { + error("sc_read_pubkey failed: %s", sc_strerror(r)); + key_free(k); + continue; + } + keys[real_count] = k; + real_count++; + k = key_new(KEY_RSA1); + if (k == NULL) + break; + convert_rsa_to_rsa1(keys[real_count-1], k); + keys[real_count] = k; + real_count++; + } + keys[real_count] = NULL; + + return keys; +err: + sc_close(); + return NULL; +} + +int +sc_put_key(Key *prv, const char *id) +{ + error("key uploading not yet supported"); + return -1; +} + +#endif /* SMARTCARD */ |