/* v3_scts.c */

/*

 * Written by Rob Stradling (rob@comodo.com) for the OpenSSL project 2014.

 */

/* ====================================================================

 * Copyright (c) 2014 The OpenSSL Project.  All rights reserved.

 *

 * 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.

 *

 * 3. All advertising materials mentioning features or use of this

 *    software must display the following acknowledgment:

 *    "This product includes software developed by the OpenSSL Project

 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"

 *

 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to

 *    endorse or promote products derived from this software without

 *    prior written permission. For written permission, please contact

 *    licensing@OpenSSL.org.

 *

 * 5. Products derived from this software may not be called "OpenSSL"

 *    nor may "OpenSSL" appear in their names without prior written

 *    permission of the OpenSSL Project.

 *

 * 6. Redistributions of any form whatsoever must retain the following

 *    acknowledgment:

 *    "This product includes software developed by the OpenSSL Project

 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"

 *

 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY

 * EXPRESSED 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 OpenSSL PROJECT OR

 * ITS CONTRIBUTORS 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.

 * ====================================================================

 *

 * This product includes cryptographic software written by Eric Young

 * (eay@cryptsoft.com).  This product includes software written by Tim

 * Hudson (tjh@cryptsoft.com).

 *

 */

#include <stdio.h>

#include "cryptlib.h"

#include <openssl/asn1.h>

#include <openssl/x509v3.h>

/* Signature and hash algorithms from RFC 5246 */

#define TLSEXT_hash_sha256                              4

#define TLSEXT_signature_rsa                            1

#define TLSEXT_signature_ecdsa                          3

#define n2s(c,s)        ((s=(((unsigned int)(c[0]))<< 8)| \

                            (((unsigned int)(c[1]))    )),c+=2)

#if (defined(_WIN32) || defined(_WIN64)) && !defined(__MINGW32__)

# define SCT_TIMESTAMP unsigned __int64

#elif defined(__arch64__)

# define SCT_TIMESTAMP unsigned long

#else

# define SCT_TIMESTAMP unsigned long long

#endif

#define n2l8(c,l)       (l =((SCT_TIMESTAMP)(*((c)++)))<<56, \

                         l|=((SCT_TIMESTAMP)(*((c)++)))<<48, \

                         l|=((SCT_TIMESTAMP)(*((c)++)))<<40, \

                         l|=((SCT_TIMESTAMP)(*((c)++)))<<32, \

                         l|=((SCT_TIMESTAMP)(*((c)++)))<<24, \

                         l|=((SCT_TIMESTAMP)(*((c)++)))<<16, \

                         l|=((SCT_TIMESTAMP)(*((c)++)))<< 8, \

                         l|=((SCT_TIMESTAMP)(*((c)++))))

typedef struct SCT_st {

    /* The encoded SCT */

    unsigned char *sct;

    unsigned short sctlen;

    /*

     * Components of the SCT.  "logid", "ext" and "sig" point to addresses

     * inside "sct".

     */

    unsigned char version;

    unsigned char *logid;

    unsigned short logidlen;

    SCT_TIMESTAMP timestamp;

    unsigned char *ext;

    unsigned short extlen;

    unsigned char hash_alg;

    unsigned char sig_alg;

    unsigned char *sig;

    unsigned short siglen;

} SCT;

DECLARE_STACK_OF(SCT)

static void SCT_LIST_free(STACK_OF(SCT) *a);

static STACK_OF(SCT) *d2i_SCT_LIST(STACK_OF(SCT) **a,

                                   const unsigned char **pp, long length);

static int i2r_SCT_LIST(X509V3_EXT_METHOD *method, STACK_OF(SCT) *sct_list,

                        BIO *out, int indent);

const X509V3_EXT_METHOD v3_ct_scts[] = {

    {NID_ct_precert_scts, 0, NULL,

     0, (X509V3_EXT_FREE)SCT_LIST_free,

     (X509V3_EXT_D2I)d2i_SCT_LIST, 0,

     0, 0, 0, 0,

     (X509V3_EXT_I2R)i2r_SCT_LIST, 0,

     NULL},

    {NID_ct_cert_scts, 0, NULL,

     0, (X509V3_EXT_FREE)SCT_LIST_free,

     (X509V3_EXT_D2I)d2i_SCT_LIST, 0,

     0, 0, 0, 0,

     (X509V3_EXT_I2R)i2r_SCT_LIST, 0,

     NULL},

};

static void tls12_signature_print(BIO *out, const unsigned char hash_alg,

                                  const unsigned char sig_alg)

{

    int nid = NID_undef;

    /* RFC6962 only permits two signature algorithms */

    if (hash_alg == TLSEXT_hash_sha256) {

        if (sig_alg == TLSEXT_signature_rsa)

            nid = NID_sha256WithRSAEncryption;

        else if (sig_alg == TLSEXT_signature_ecdsa)

            nid = NID_ecdsa_with_SHA256;

    }

    if (nid == NID_undef)

        BIO_printf(out, "%02X%02X", hash_alg, sig_alg);

    else

        BIO_printf(out, "%s", OBJ_nid2ln(nid));

}

static void timestamp_print(BIO *out, SCT_TIMESTAMP timestamp)

{

    ASN1_GENERALIZEDTIME *gen;

    char genstr[20];

    gen = ASN1_GENERALIZEDTIME_new();

    ASN1_GENERALIZEDTIME_adj(gen, (time_t)0,

                             (int)(timestamp / 86400000),

                             (timestamp % 86400000) / 1000);

    /*

     * Note GeneralizedTime from ASN1_GENERALIZETIME_adj is always 15

     * characters long with a final Z. Update it with fractional seconds.

     */

    BIO_snprintf(genstr, sizeof(genstr), "%.14s.%03dZ",

                 ASN1_STRING_data(gen), (unsigned int)(timestamp % 1000));

    ASN1_GENERALIZEDTIME_set_string(gen, genstr);

    ASN1_GENERALIZEDTIME_print(out, gen);

    ASN1_GENERALIZEDTIME_free(gen);

}

static void SCT_free(SCT *sct)

{

    if (sct) {

        if (sct->sct)

            OPENSSL_free(sct->sct);

        OPENSSL_free(sct);

    }

}

static void SCT_LIST_free(STACK_OF(SCT) *a)

{

    sk_SCT_pop_free(a, SCT_free);

}

static STACK_OF(SCT) *d2i_SCT_LIST(STACK_OF(SCT) **a,

                                   const unsigned char **pp, long length)

{

    ASN1_OCTET_STRING *oct = NULL;

    STACK_OF(SCT) *sk = NULL;

    SCT *sct;

    unsigned char *p, *p2;

    unsigned short listlen, sctlen = 0, fieldlen;

    const unsigned char *q = *pp;

    if (d2i_ASN1_OCTET_STRING(&oct, &q, length) == NULL)

        return NULL;

    if (oct->length < 2)

        goto done;

    p = oct->data;

    n2s(p, listlen);

    if (listlen != oct->length - 2)

        goto done;

    if ((sk = sk_SCT_new_null()) == NULL)

        goto done;

    while (listlen > 0) {

        if (listlen < 2)

            goto err;

        n2s(p, sctlen);

        listlen -= 2;

        if ((sctlen < 1) || (sctlen > listlen))

            goto err;

        listlen -= sctlen;

        sct = OPENSSL_malloc(sizeof(SCT));

        if (!sct)

            goto err;

        if (!sk_SCT_push(sk, sct)) {

            OPENSSL_free(sct);

            goto err;

        }

        sct->sct = OPENSSL_malloc(sctlen);

        if (!sct->sct)

            goto err;

        memcpy(sct->sct, p, sctlen);

        sct->sctlen = sctlen;

        p += sctlen;

        p2 = sct->sct;

        sct->version = *p2++;

        if (sct->version == 0) { /* SCT v1 */

            /*-

             * Fixed-length header:

             *              struct {

             * (1 byte)       Version sct_version;

             * (32 bytes)     LogID id;

             * (8 bytes)      uint64 timestamp;

             * (2 bytes + ?)  CtExtensions extensions;

             */

            if (sctlen < 43)

                goto err;

            sctlen -= 43;

            sct->logid = p2;

            sct->logidlen = 32;

            p2 += 32;

            n2l8(p2, sct->timestamp);

            n2s(p2, fieldlen);

            if (sctlen < fieldlen)

                goto err;

            sct->ext = p2;

            sct->extlen = fieldlen;

            p2 += fieldlen;

            sctlen -= fieldlen;

            /*-

             * digitally-signed struct header:

             * (1 byte)       Hash algorithm

             * (1 byte)       Signature algorithm

             * (2 bytes + ?)  Signature

             */

            if (sctlen < 4)

                goto err;

            sctlen -= 4;

            sct->hash_alg = *p2++;

            sct->sig_alg = *p2++;

            n2s(p2, fieldlen);

            if (sctlen != fieldlen)

                goto err;

            sct->sig = p2;

            sct->siglen = fieldlen;

        }

    }

 done:

    ASN1_OCTET_STRING_free(oct);

    *pp = q;

    return sk;

 err:

    SCT_LIST_free(sk);

    sk = NULL;

    goto done;

}

static int i2r_SCT_LIST(X509V3_EXT_METHOD *method, STACK_OF(SCT) *sct_list,

                        BIO *out, int indent)

{

    SCT *sct;

    int i;

    for (i = 0; i < sk_SCT_num(sct_list);) {

        sct = sk_SCT_value(sct_list, i);

        BIO_printf(out, "%*sSigned Certificate Timestamp:", indent, "");

        BIO_printf(out, "\n%*sVersion   : ", indent + 4, "");

        if (sct->version == 0) { /* SCT v1 */

            BIO_printf(out, "v1(0)");

            BIO_printf(out, "\n%*sLog ID    : ", indent + 4, "");

            BIO_hex_string(out, indent + 16, 16, sct->logid, sct->logidlen);

            BIO_printf(out, "\n%*sTimestamp : ", indent + 4, "");

            timestamp_print(out, sct->timestamp);

            BIO_printf(out, "\n%*sExtensions: ", indent + 4, "");

            if (sct->extlen == 0)

                BIO_printf(out, "none");

            else

                BIO_hex_string(out, indent + 16, 16, sct->ext, sct->extlen);

            BIO_printf(out, "\n%*sSignature : ", indent + 4, "");

            tls12_signature_print(out, sct->hash_alg, sct->sig_alg);

            BIO_printf(out, "\n%*s            ", indent + 4, "");

            BIO_hex_string(out, indent + 16, 16, sct->sig, sct->siglen);

        } else {                /* Unknown version */

            BIO_printf(out, "unknown\n%*s", indent + 16, "");

            BIO_hex_string(out, indent + 16, 16, sct->sct, sct->sctlen);

        }

        if (++i < sk_SCT_num(sct_list))

            BIO_printf(out, "\n");

    }

    return 1;

}