text: /*
   * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
   * 2006.
   */
  /* ====================================================================
   * Copyright (c) 2006 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 "internal/cryptlib.h"
  #include <openssl/x509.h>
  #include <openssl/asn1.h>
  #include <openssl/dsa.h>
  #include <openssl/bn.h>
  #ifndef OPENSSL_NO_CMS
  # include <openssl/cms.h>
  #endif
  #include "internal/asn1_int.h"
  
  static int dsa_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey)
  {
      const unsigned char *p, *pm;
      int pklen, pmlen;
      int ptype;
      void *pval;
      ASN1_STRING *pstr;
      X509_ALGOR *palg;
      ASN1_INTEGER *public_key = NULL;
  
      DSA *dsa = NULL;
  
      if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, &palg, pubkey))
          return 0;
      X509_ALGOR_get0(NULL, &ptype, &pval, palg);
  
      if (ptype == V_ASN1_SEQUENCE) {
          pstr = pval;
          pm = pstr->data;
          pmlen = pstr->length;
  
          if ((dsa = d2i_DSAparams(NULL, &pm, pmlen)) == NULL) {
              DSAerr(DSA_F_DSA_PUB_DECODE, DSA_R_DECODE_ERROR);
              goto err;
          }
  
      } else if ((ptype == V_ASN1_NULL) || (ptype == V_ASN1_UNDEF)) {
          if ((dsa = DSA_new()) == NULL) {
              DSAerr(DSA_F_DSA_PUB_DECODE, ERR_R_MALLOC_FAILURE);
              goto err;
          }
      } else {
          DSAerr(DSA_F_DSA_PUB_DECODE, DSA_R_PARAMETER_ENCODING_ERROR);
          goto err;
      }
  
      if ((public_key = d2i_ASN1_INTEGER(NULL, &p, pklen)) == NULL) {
          DSAerr(DSA_F_DSA_PUB_DECODE, DSA_R_DECODE_ERROR);
          goto err;
      }
  
      if ((dsa->pub_key = ASN1_INTEGER_to_BN(public_key, NULL)) == NULL) {
          DSAerr(DSA_F_DSA_PUB_DECODE, DSA_R_BN_DECODE_ERROR);
          goto err;
      }
  
      ASN1_INTEGER_free(public_key);
      EVP_PKEY_assign_DSA(pkey, dsa);
      return 1;
  
   err:
      ASN1_INTEGER_free(public_key);
      DSA_free(dsa);
      return 0;
  
  }
  
  static int dsa_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
  {
      DSA *dsa;
      int ptype;
      unsigned char *penc = NULL;
      int penclen;
      ASN1_STRING *str = NULL;
      ASN1_INTEGER *pubint = NULL;
  
      dsa = pkey->pkey.dsa;
      if (pkey->save_parameters && dsa->p && dsa->q && dsa->g) {
          str = ASN1_STRING_new();
          if (str == NULL) {
              DSAerr(DSA_F_DSA_PUB_ENCODE, ERR_R_MALLOC_FAILURE);
              goto err;
          }
          str->length = i2d_DSAparams(dsa, &str->data);
          if (str->length <= 0) {
              DSAerr(DSA_F_DSA_PUB_ENCODE, ERR_R_MALLOC_FAILURE);
              goto err;
          }
          ptype = V_ASN1_SEQUENCE;
      } else
          ptype = V_ASN1_UNDEF;
  
      pubint = BN_to_ASN1_INTEGER(dsa->pub_key, NULL);
  
      if (pubint == NULL) {
          DSAerr(DSA_F_DSA_PUB_ENCODE, ERR_R_MALLOC_FAILURE);
          goto err;
      }
  
      penclen = i2d_ASN1_INTEGER(pubint, &penc);
      ASN1_INTEGER_free(pubint);
  
      if (penclen <= 0) {
          DSAerr(DSA_F_DSA_PUB_ENCODE, ERR_R_MALLOC_FAILURE);
          goto err;
      }
  
      if (X509_PUBKEY_set0_param(pk, OBJ_nid2obj(EVP_PKEY_DSA),
                                 ptype, str, penc, penclen))
          return 1;
  
   err:
      OPENSSL_free(penc);
      ASN1_STRING_free(str);
  
      return 0;
  }
  
  /*
   * In PKCS#8 DSA: you just get a private key integer and parameters in the
   * AlgorithmIdentifier the pubkey must be recalculated.
   */
  
  static int dsa_priv_decode(EVP_PKEY *pkey, PKCS8_PRIV_KEY_INFO *p8)
  {
      const unsigned char *p, *pm;
      int pklen, pmlen;
      int ptype;
      void *pval;
      ASN1_STRING *pstr;
      X509_ALGOR *palg;
      ASN1_INTEGER *privkey = NULL;
      BN_CTX *ctx = NULL;
  
      STACK_OF(ASN1_TYPE) *ndsa = NULL;
      DSA *dsa = NULL;
  
      if (!PKCS8_pkey_get0(NULL, &p, &pklen, &palg, p8))
          return 0;
      X509_ALGOR_get0(NULL, &ptype, &pval, palg);
  
      /* Check for broken DSA PKCS#8, UGH! */
      if (*p == (V_ASN1_SEQUENCE | V_ASN1_CONSTRUCTED)) {
          ASN1_TYPE *t1, *t2;
          if ((ndsa = d2i_ASN1_SEQUENCE_ANY(NULL, &p, pklen)) == NULL)
              goto decerr;
          if (sk_ASN1_TYPE_num(ndsa) != 2)
              goto decerr;
          /*-
           * Handle Two broken types:
           * SEQUENCE {parameters, priv_key}
           * SEQUENCE {pub_key, priv_key}
           */
  
          t1 = sk_ASN1_TYPE_value(ndsa, 0);
          t2 = sk_ASN1_TYPE_value(ndsa, 1);
          if (t1->type == V_ASN1_SEQUENCE) {
              p8->broken = PKCS8_EMBEDDED_PARAM;
              pval = t1->value.ptr;
          } else if (ptype == V_ASN1_SEQUENCE)
              p8->broken = PKCS8_NS_DB;
          else
              goto decerr;
  
          if (t2->type != V_ASN1_INTEGER)
              goto decerr;
  
          privkey = t2->value.integer;
      } else {
          const unsigned char *q = p;
          if ((privkey = d2i_ASN1_INTEGER(NULL, &p, pklen)) == NULL)
              goto decerr;
          if (privkey->type == V_ASN1_NEG_INTEGER) {
              p8->broken = PKCS8_NEG_PRIVKEY;
              ASN1_STRING_clear_free(privkey);
              if ((privkey = d2i_ASN1_UINTEGER(NULL, &q, pklen)) == NULL)
                  goto decerr;
          }
          if (ptype != V_ASN1_SEQUENCE)
              goto decerr;
      }
  
      pstr = pval;
      pm = pstr->data;
      pmlen = pstr->length;
      if ((dsa = d2i_DSAparams(NULL, &pm, pmlen)) == NULL)
          goto decerr;
      /* We have parameters now set private key */
      if ((dsa->priv_key = BN_secure_new()) == NULL
          || !ASN1_INTEGER_to_BN(privkey, dsa->priv_key)) {
          DSAerr(DSA_F_DSA_PRIV_DECODE, DSA_R_BN_ERROR);
          goto dsaerr;
      }
      /* Calculate public key */
      if ((dsa->pub_key = BN_new()) == NULL) {
          DSAerr(DSA_F_DSA_PRIV_DECODE, ERR_R_MALLOC_FAILURE);
          goto dsaerr;
      }
      if ((ctx = BN_CTX_new()) == NULL) {
          DSAerr(DSA_F_DSA_PRIV_DECODE, ERR_R_MALLOC_FAILURE);
          goto dsaerr;
      }
  
      if (!BN_mod_exp(dsa->pub_key, dsa->g, dsa->priv_key, dsa->p, ctx)) {
          DSAerr(DSA_F_DSA_PRIV_DECODE, DSA_R_BN_ERROR);
          goto dsaerr;
      }
  
      EVP_PKEY_assign_DSA(pkey, dsa);
      BN_CTX_free(ctx);
      if (ndsa)
          sk_ASN1_TYPE_pop_free(ndsa, ASN1_TYPE_free);
      else
          ASN1_STRING_clear_free(privkey);
  
      return 1;
  
   decerr:
      DSAerr(DSA_F_DSA_PRIV_DECODE, EVP_R_DECODE_ERROR);
   dsaerr:
      BN_CTX_free(ctx);
      ASN1_STRING_clear_free(privkey);
      sk_ASN1_TYPE_pop_free(ndsa, ASN1_TYPE_free);
      DSA_free(dsa);
      return 0;
  }
  
  static int dsa_priv_encode(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pkey)
  {
      ASN1_STRING *params = NULL;
      ASN1_INTEGER *prkey = NULL;
      unsigned char *dp = NULL;
      int dplen;
  
      if (!pkey->pkey.dsa || !pkey->pkey.dsa->priv_key) {
          DSAerr(DSA_F_DSA_PRIV_ENCODE, DSA_R_MISSING_PARAMETERS);
          goto err;
      }
  
      params = ASN1_STRING_new();
  
      if (params == NULL) {
          DSAerr(DSA_F_DSA_PRIV_ENCODE, ERR_R_MALLOC_FAILURE);
          goto err;
      }
  
      params->length = i2d_DSAparams(pkey->pkey.dsa, &params->data);
      if (params->length <= 0) {
          DSAerr(DSA_F_DSA_PRIV_ENCODE, ERR_R_MALLOC_FAILURE);
          goto err;
      }
      params->type = V_ASN1_SEQUENCE;
  
      /* Get private key into integer */
      prkey = BN_to_ASN1_INTEGER(pkey->pkey.dsa->priv_key, NULL);
  
      if (!prkey) {
          DSAerr(DSA_F_DSA_PRIV_ENCODE, DSA_R_BN_ERROR);
          goto err;
      }
  
      dplen = i2d_ASN1_INTEGER(prkey, &dp);
  
      ASN1_STRING_clear_free(prkey);
      prkey = NULL;
  
      if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(NID_dsa), 0,
                           V_ASN1_SEQUENCE, params, dp, dplen))
          goto err;
  
      return 1;
  
   err:
      OPENSSL_free(dp);
      ASN1_STRING_free(params);
      ASN1_STRING_clear_free(prkey);
      return 0;
  }
  
  static int int_dsa_size(const EVP_PKEY *pkey)
  {
      return (DSA_size(pkey->pkey.dsa));
  }
  
  static int dsa_bits(const EVP_PKEY *pkey)
  {
      return BN_num_bits(pkey->pkey.dsa->p);
  }
  
  static int dsa_security_bits(const EVP_PKEY *pkey)
  {
      return DSA_security_bits(pkey->pkey.dsa);
  }
  
  static int dsa_missing_parameters(const EVP_PKEY *pkey)
  {
      DSA *dsa;
      dsa = pkey->pkey.dsa;
      if ((dsa->p == NULL) || (dsa->q == NULL) || (dsa->g == NULL))
          return 1;
      return 0;
  }
  
  static int dsa_copy_parameters(EVP_PKEY *to, const EVP_PKEY *from)
  {
      BIGNUM *a;
  
      if ((a = BN_dup(from->pkey.dsa->p)) == NULL)
          return 0;
      BN_free(to->pkey.dsa->p);
      to->pkey.dsa->p = a;
  
      if ((a = BN_dup(from->pkey.dsa->q)) == NULL)
          return 0;
      BN_free(to->pkey.dsa->q);
      to->pkey.dsa->q = a;
  
      if ((a = BN_dup(from->pkey.dsa->g)) == NULL)
          return 0;
      BN_free(to->pkey.dsa->g);
      to->pkey.dsa->g = a;
      return 1;
  }
  
  static int dsa_cmp_parameters(const EVP_PKEY *a, const EVP_PKEY *b)
  {
      if (BN_cmp(a->pkey.dsa->p, b->pkey.dsa->p) ||
          BN_cmp(a->pkey.dsa->q, b->pkey.dsa->q) ||
          BN_cmp(a->pkey.dsa->g, b->pkey.dsa->g))
          return 0;
      else
          return 1;
  }
  
  static int dsa_pub_cmp(const EVP_PKEY *a, const EVP_PKEY *b)
  {
      if (BN_cmp(b->pkey.dsa->pub_key, a->pkey.dsa->pub_key) != 0)
          return 0;
      else
          return 1;
  }
  
  static void int_dsa_free(EVP_PKEY *pkey)
  {
      DSA_free(pkey->pkey.dsa);
  }
  
  static void update_buflen(const BIGNUM *b, size_t *pbuflen)
  {
      size_t i;
      if (!b)
          return;
      if (*pbuflen < (i = (size_t)BN_num_bytes(b)))
          *pbuflen = i;
  }
  
  static int do_dsa_print(BIO *bp, const DSA *x, int off, int ptype)
  {
      unsigned char *m = NULL;
      int ret = 0;
      size_t buf_len = 0;
      const char *ktype = NULL;
  
      const BIGNUM *priv_key, *pub_key;
  
      if (ptype == 2)
          priv_key = x->priv_key;
      else
          priv_key = NULL;
  
      if (ptype > 0)
          pub_key = x->pub_key;
      else
          pub_key = NULL;
  
      if (ptype == 2)
          ktype = "Private-Key";
      else if (ptype == 1)
          ktype = "Public-Key";
      else
          ktype = "DSA-Parameters";
  
      update_buflen(x->p, &buf_len);
      update_buflen(x->q, &buf_len);
      update_buflen(x->g, &buf_len);
      update_buflen(priv_key, &buf_len);
      update_buflen(pub_key, &buf_len);
  
      m = OPENSSL_malloc(buf_len + 10);
      if (m == NULL) {
          DSAerr(DSA_F_DO_DSA_PRINT, ERR_R_MALLOC_FAILURE);
          goto err;
      }
  
      if (priv_key) {
          if (!BIO_indent(bp, off, 128))
              goto err;
          if (BIO_printf(bp, "%s: (%d bit)\n", ktype, BN_num_bits(x->p))
              <= 0)
              goto err;
      }
  
      if (!ASN1_bn_print(bp, "priv:", priv_key, m, off))
          goto err;
      if (!ASN1_bn_print(bp, "pub: ", pub_key, m, off))
          goto err;
      if (!ASN1_bn_print(bp, "P:   ", x->p, m, off))
          goto err;
      if (!ASN1_bn_print(bp, "Q:   ", x->q, m, off))
          goto err;
      if (!ASN1_bn_print(bp, "G:   ", x->g, m, off))
          goto err;
      ret = 1;
   err:
      OPENSSL_free(m);
      return (ret);
  }
  
  static int dsa_param_decode(EVP_PKEY *pkey,
                              const unsigned char **pder, int derlen)
  {
      DSA *dsa;
  
      if ((dsa = d2i_DSAparams(NULL, pder, derlen)) == NULL) {
          DSAerr(DSA_F_DSA_PARAM_DECODE, ERR_R_DSA_LIB);
          return 0;
      }
      EVP_PKEY_assign_DSA(pkey, dsa);
      return 1;
  }
  
  static int dsa_param_encode(const EVP_PKEY *pkey, unsigned char **pder)
  {
      return i2d_DSAparams(pkey->pkey.dsa, pder);
  }
  
  static int dsa_param_print(BIO *bp, const EVP_PKEY *pkey, int indent,
                             ASN1_PCTX *ctx)
  {
      return do_dsa_print(bp, pkey->pkey.dsa, indent, 0);
  }
  
  static int dsa_pub_print(BIO *bp, const EVP_PKEY *pkey, int indent,
                           ASN1_PCTX *ctx)
  {
      return do_dsa_print(bp, pkey->pkey.dsa, indent, 1);
  }
  
  static int dsa_priv_print(BIO *bp, const EVP_PKEY *pkey, int indent,
                            ASN1_PCTX *ctx)
  {
      return do_dsa_print(bp, pkey->pkey.dsa, indent, 2);
  }
  
  static int old_dsa_priv_decode(EVP_PKEY *pkey,
                                 const unsigned char **pder, int derlen)
  {
      DSA *dsa;
  
      if ((dsa = d2i_DSAPrivateKey(NULL, pder, derlen)) == NULL) {
          DSAerr(DSA_F_OLD_DSA_PRIV_DECODE, ERR_R_DSA_LIB);
          return 0;
      }
      EVP_PKEY_assign_DSA(pkey, dsa);
      return 1;
  }
  
  static int old_dsa_priv_encode(const EVP_PKEY *pkey, unsigned char **pder)
  {
      return i2d_DSAPrivateKey(pkey->pkey.dsa, pder);
  }
  
  static int dsa_sig_print(BIO *bp, const X509_ALGOR *sigalg,
                           const ASN1_STRING *sig, int indent, ASN1_PCTX *pctx)
  {
      DSA_SIG *dsa_sig;
      const unsigned char *p;
      if (!sig) {
          if (BIO_puts(bp, "\n") <= 0)
              return 0;
          else
              return 1;
      }
      p = sig->data;
      dsa_sig = d2i_DSA_SIG(NULL, &p, sig->length);
      if (dsa_sig) {
          int rv = 0;
          size_t buf_len = 0;
          unsigned char *m = NULL;
          update_buflen(dsa_sig->r, &buf_len);
          update_buflen(dsa_sig->s, &buf_len);
          m = OPENSSL_malloc(buf_len + 10);
          if (m == NULL) {
              DSAerr(DSA_F_DSA_SIG_PRINT, ERR_R_MALLOC_FAILURE);
              goto err;
          }
  
          if (BIO_write(bp, "\n", 1) != 1)
              goto err;
  
          if (!ASN1_bn_print(bp, "r:   ", dsa_sig->r, m, indent))
              goto err;
          if (!ASN1_bn_print(bp, "s:   ", dsa_sig->s, m, indent))
              goto err;
          rv = 1;
   err:
          OPENSSL_free(m);
          DSA_SIG_free(dsa_sig);
          return rv;
      }
      return X509_signature_dump(bp, sig, indent);
  }
  
  static int dsa_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2)
  {
      switch (op) {
      case ASN1_PKEY_CTRL_PKCS7_SIGN:
          if (arg1 == 0) {
              int snid, hnid;
              X509_ALGOR *alg1, *alg2;
              PKCS7_SIGNER_INFO_get0_algs(arg2, NULL, &alg1, &alg2);
              if (alg1 == NULL || alg1->algorithm == NULL)
                  return -1;
              hnid = OBJ_obj2nid(alg1->algorithm);
              if (hnid == NID_undef)
                  return -1;
              if (!OBJ_find_sigid_by_algs(&snid, hnid, EVP_PKEY_id(pkey)))
                  return -1;
              X509_ALGOR_set0(alg2, OBJ_nid2obj(snid), V_ASN1_UNDEF, 0);
          }
          return 1;
  #ifndef OPENSSL_NO_CMS
      case ASN1_PKEY_CTRL_CMS_SIGN:
          if (arg1 == 0) {
              int snid, hnid;
              X509_ALGOR *alg1, *alg2;
              CMS_SignerInfo_get0_algs(arg2, NULL, NULL, &alg1, &alg2);
              if (alg1 == NULL || alg1->algorithm == NULL)
                  return -1;
              hnid = OBJ_obj2nid(alg1->algorithm);
              if (hnid == NID_undef)
                  return -1;
              if (!OBJ_find_sigid_by_algs(&snid, hnid, EVP_PKEY_id(pkey)))
                  return -1;
              X509_ALGOR_set0(alg2, OBJ_nid2obj(snid), V_ASN1_UNDEF, 0);
          }
          return 1;
  
      case ASN1_PKEY_CTRL_CMS_RI_TYPE:
          *(int *)arg2 = CMS_RECIPINFO_NONE;
          return 1;
  #endif
  
      case ASN1_PKEY_CTRL_DEFAULT_MD_NID:
          *(int *)arg2 = NID_sha256;
          return 2;
  
      default:
          return -2;
  
      }
  
  }
  
  /* NB these are sorted in pkey_id order, lowest first */
  
  const EVP_PKEY_ASN1_METHOD dsa_asn1_meths[] = {
  
      {
       EVP_PKEY_DSA2,
       EVP_PKEY_DSA,
       ASN1_PKEY_ALIAS},
  
      {
       EVP_PKEY_DSA1,
       EVP_PKEY_DSA,
       ASN1_PKEY_ALIAS},
  
      {
       EVP_PKEY_DSA4,
       EVP_PKEY_DSA,
       ASN1_PKEY_ALIAS},
  
      {
       EVP_PKEY_DSA3,
       EVP_PKEY_DSA,
       ASN1_PKEY_ALIAS},
  
      {
       EVP_PKEY_DSA,
       EVP_PKEY_DSA,
       0,
  
       "DSA",
       "OpenSSL DSA method",
  
       dsa_pub_decode,
       dsa_pub_encode,
       dsa_pub_cmp,
       dsa_pub_print,
  
       dsa_priv_decode,
       dsa_priv_encode,
       dsa_priv_print,
  
       int_dsa_size,
       dsa_bits,
       dsa_security_bits,
  
       dsa_param_decode,
       dsa_param_encode,
       dsa_missing_parameters,
       dsa_copy_parameters,
       dsa_cmp_parameters,
       dsa_param_print,
       dsa_sig_print,
  
       int_dsa_free,
       dsa_pkey_ctrl,
       old_dsa_priv_decode,
       old_dsa_priv_encode}
  };
  