text: /*
   * Copyright 1995-2022 The OpenSSL Project Authors. All Rights Reserved.
   *
   * Licensed under the Apache License 2.0 (the "License").  You may not use
   * this file except in compliance with the License.  You can obtain a copy
   * in the file LICENSE in the source distribution or at
   * https://www.openssl.org/source/license.html
   */
  
  #include <stdio.h>
  #include "internal/cryptlib.h"
  #include <openssl/objects.h>
  #include <openssl/x509.h>
  #include <openssl/pkcs7.h>
  #include "crypto/asn1.h"
  #include "crypto/evp.h"
  #include "crypto/x509.h" /* for sk_X509_add1_cert() */
  #include "pk7_local.h"
  
  long PKCS7_ctrl(PKCS7 *p7, int cmd, long larg, char *parg)
  {
      int nid;
      long ret;
  
      nid = OBJ_obj2nid(p7->type);
  
      switch (cmd) {
      /* NOTE(emilia): does not support detached digested data. */
      case PKCS7_OP_SET_DETACHED_SIGNATURE:
          if (nid == NID_pkcs7_signed) {
              ret = p7->detached = (int)larg;
              if (ret && PKCS7_type_is_data(p7->d.sign->contents)) {
                  ASN1_OCTET_STRING *os;
                  os = p7->d.sign->contents->d.data;
                  ASN1_OCTET_STRING_free(os);
                  p7->d.sign->contents->d.data = NULL;
              }
          } else {
              ERR_raise(ERR_LIB_PKCS7,
                        PKCS7_R_OPERATION_NOT_SUPPORTED_ON_THIS_TYPE);
              ret = 0;
          }
          break;
      case PKCS7_OP_GET_DETACHED_SIGNATURE:
          if (nid == NID_pkcs7_signed) {
              if (p7->d.sign == NULL || p7->d.sign->contents->d.ptr == NULL)
                  ret = 1;
              else
                  ret = 0;
  
              p7->detached = ret;
          } else {
              ERR_raise(ERR_LIB_PKCS7,
                        PKCS7_R_OPERATION_NOT_SUPPORTED_ON_THIS_TYPE);
              ret = 0;
          }
  
          break;
      default:
          ERR_raise(ERR_LIB_PKCS7, PKCS7_R_UNKNOWN_OPERATION);
          ret = 0;
      }
      return ret;
  }
  
  int PKCS7_content_new(PKCS7 *p7, int type)
  {
      PKCS7 *ret = NULL;
  
      if ((ret = PKCS7_new()) == NULL)
          goto err;
      if (!PKCS7_set_type(ret, type))
          goto err;
      if (!PKCS7_set_content(p7, ret))
          goto err;
  
      return 1;
   err:
      PKCS7_free(ret);
      return 0;
  }
  
  int PKCS7_set_content(PKCS7 *p7, PKCS7 *p7_data)
  {
      int i;
  
      i = OBJ_obj2nid(p7->type);
      switch (i) {
      case NID_pkcs7_signed:
          PKCS7_free(p7->d.sign->contents);
          p7->d.sign->contents = p7_data;
          break;
      case NID_pkcs7_digest:
          PKCS7_free(p7->d.digest->contents);
          p7->d.digest->contents = p7_data;
          break;
      case NID_pkcs7_data:
      case NID_pkcs7_enveloped:
      case NID_pkcs7_signedAndEnveloped:
      case NID_pkcs7_encrypted:
      default:
          ERR_raise(ERR_LIB_PKCS7, PKCS7_R_UNSUPPORTED_CONTENT_TYPE);
          goto err;
      }
      return 1;
   err:
      return 0;
  }
  
  int PKCS7_set_type(PKCS7 *p7, int type)
  {
      ASN1_OBJECT *obj;
  
      /*
       * PKCS7_content_free(p7);
       */
      obj = OBJ_nid2obj(type);    /* will not fail */
  
      switch (type) {
      case NID_pkcs7_signed:
          p7->type = obj;
          if ((p7->d.sign = PKCS7_SIGNED_new()) == NULL)
              goto err;
          if (!ASN1_INTEGER_set(p7->d.sign->version, 1)) {
              PKCS7_SIGNED_free(p7->d.sign);
              p7->d.sign = NULL;
              goto err;
          }
          break;
      case NID_pkcs7_data:
          p7->type = obj;
          if ((p7->d.data = ASN1_OCTET_STRING_new()) == NULL)
              goto err;
          break;
      case NID_pkcs7_signedAndEnveloped:
          p7->type = obj;
          if ((p7->d.signed_and_enveloped = PKCS7_SIGN_ENVELOPE_new())
              == NULL)
              goto err;
          if (!ASN1_INTEGER_set(p7->d.signed_and_enveloped->version, 1))
              goto err;
          p7->d.signed_and_enveloped->enc_data->content_type
              = OBJ_nid2obj(NID_pkcs7_data);
          break;
      case NID_pkcs7_enveloped:
          p7->type = obj;
          if ((p7->d.enveloped = PKCS7_ENVELOPE_new())
              == NULL)
              goto err;
          if (!ASN1_INTEGER_set(p7->d.enveloped->version, 0))
              goto err;
          p7->d.enveloped->enc_data->content_type = OBJ_nid2obj(NID_pkcs7_data);
          break;
      case NID_pkcs7_encrypted:
          p7->type = obj;
          if ((p7->d.encrypted = PKCS7_ENCRYPT_new())
              == NULL)
              goto err;
          if (!ASN1_INTEGER_set(p7->d.encrypted->version, 0))
              goto err;
          p7->d.encrypted->enc_data->content_type = OBJ_nid2obj(NID_pkcs7_data);
          break;
  
      case NID_pkcs7_digest:
          p7->type = obj;
          if ((p7->d.digest = PKCS7_DIGEST_new())
              == NULL)
              goto err;
          if (!ASN1_INTEGER_set(p7->d.digest->version, 0))
              goto err;
          break;
      default:
          ERR_raise(ERR_LIB_PKCS7, PKCS7_R_UNSUPPORTED_CONTENT_TYPE);
          goto err;
      }
      return 1;
   err:
      return 0;
  }
  
  int PKCS7_set0_type_other(PKCS7 *p7, int type, ASN1_TYPE *other)
  {
      p7->type = OBJ_nid2obj(type);
      p7->d.other = other;
      return 1;
  }
  
  int PKCS7_add_signer(PKCS7 *p7, PKCS7_SIGNER_INFO *psi)
  {
      int i, j;
      ASN1_OBJECT *obj;
      X509_ALGOR *alg;
      STACK_OF(PKCS7_SIGNER_INFO) *signer_sk;
      STACK_OF(X509_ALGOR) *md_sk;
  
      i = OBJ_obj2nid(p7->type);
      switch (i) {
      case NID_pkcs7_signed:
          signer_sk = p7->d.sign->signer_info;
          md_sk = p7->d.sign->md_algs;
          break;
      case NID_pkcs7_signedAndEnveloped:
          signer_sk = p7->d.signed_and_enveloped->signer_info;
          md_sk = p7->d.signed_and_enveloped->md_algs;
          break;
      default:
          ERR_raise(ERR_LIB_PKCS7, PKCS7_R_WRONG_CONTENT_TYPE);
          return 0;
      }
  
      obj = psi->digest_alg->algorithm;
      /* If the digest is not currently listed, add it */
      j = 0;
      for (i = 0; i < sk_X509_ALGOR_num(md_sk); i++) {
          alg = sk_X509_ALGOR_value(md_sk, i);
          if (OBJ_cmp(obj, alg->algorithm) == 0) {
              j = 1;
              break;
          }
      }
      if (!j) {                   /* we need to add another algorithm */
          int nid;
  
          if ((alg = X509_ALGOR_new()) == NULL
              || (alg->parameter = ASN1_TYPE_new()) == NULL) {
              X509_ALGOR_free(alg);
              ERR_raise(ERR_LIB_PKCS7, ERR_R_MALLOC_FAILURE);
              return 0;
          }
          /*
           * If there is a constant copy of the ASN1 OBJECT in libcrypto, then
           * use that.  Otherwise, use a dynamically duplicated copy
           */
          if ((nid = OBJ_obj2nid(obj)) != NID_undef)
              alg->algorithm = OBJ_nid2obj(nid);
          else
              alg->algorithm = OBJ_dup(obj);
          alg->parameter->type = V_ASN1_NULL;
          if (alg->algorithm == NULL || !sk_X509_ALGOR_push(md_sk, alg)) {
              X509_ALGOR_free(alg);
              return 0;
          }
      }
  
      psi->ctx = ossl_pkcs7_get0_ctx(p7);
      if (!sk_PKCS7_SIGNER_INFO_push(signer_sk, psi))
          return 0;
      return 1;
  }
  
  int PKCS7_add_certificate(PKCS7 *p7, X509 *x509)
  {
      int i;
      STACK_OF(X509) **sk;
  
      i = OBJ_obj2nid(p7->type);
      switch (i) {
      case NID_pkcs7_signed:
          sk = &(p7->d.sign->cert);
          break;
      case NID_pkcs7_signedAndEnveloped:
          sk = &(p7->d.signed_and_enveloped->cert);
          break;
      default:
          ERR_raise(ERR_LIB_PKCS7, PKCS7_R_WRONG_CONTENT_TYPE);
          return 0;
      }
  
      return ossl_x509_add_cert_new(sk, x509, X509_ADD_FLAG_UP_REF);
  }
  
  int PKCS7_add_crl(PKCS7 *p7, X509_CRL *crl)
  {
      int i;
      STACK_OF(X509_CRL) **sk;
  
      i = OBJ_obj2nid(p7->type);
      switch (i) {
      case NID_pkcs7_signed:
          sk = &(p7->d.sign->crl);
          break;
      case NID_pkcs7_signedAndEnveloped:
          sk = &(p7->d.signed_and_enveloped->crl);
          break;
      default:
          ERR_raise(ERR_LIB_PKCS7, PKCS7_R_WRONG_CONTENT_TYPE);
          return 0;
      }
  
      if (*sk == NULL)
          *sk = sk_X509_CRL_new_null();
      if (*sk == NULL) {
          ERR_raise(ERR_LIB_PKCS7, ERR_R_MALLOC_FAILURE);
          return 0;
      }
  
      X509_CRL_up_ref(crl);
      if (!sk_X509_CRL_push(*sk, crl)) {
          X509_CRL_free(crl);
          return 0;
      }
      return 1;
  }
  
  static int pkcs7_ecdsa_or_dsa_sign_verify_setup(PKCS7_SIGNER_INFO *si,
                                                  int verify)
  {
      if (!verify) {
          int snid, hnid;
          X509_ALGOR *alg1, *alg2;
          EVP_PKEY *pkey = si->pkey;
  
          PKCS7_SIGNER_INFO_get0_algs(si, 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_get_id(pkey)))
              return -1;
          return X509_ALGOR_set0(alg2, OBJ_nid2obj(snid), V_ASN1_UNDEF, NULL);
      }
      return 1;
  }
  
  static int pkcs7_rsa_sign_verify_setup(PKCS7_SIGNER_INFO *si, int verify)
  {
      if (!verify) {
          X509_ALGOR *alg = NULL;
  
          PKCS7_SIGNER_INFO_get0_algs(si, NULL, NULL, &alg);
          if (alg != NULL)
              return X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsaEncryption),
                                     V_ASN1_NULL, NULL);
      }
      return 1;
  }
  
  int PKCS7_SIGNER_INFO_set(PKCS7_SIGNER_INFO *p7i, X509 *x509, EVP_PKEY *pkey,
                            const EVP_MD *dgst)
  {
      int ret;
  
      /* We now need to add another PKCS7_SIGNER_INFO entry */
      if (!ASN1_INTEGER_set(p7i->version, 1))
          return 0;
      if (!X509_NAME_set(&p7i->issuer_and_serial->issuer,
                         X509_get_issuer_name(x509)))
          return 0;
  
      /*
       * because ASN1_INTEGER_set is used to set a 'long' we will do things the
       * ugly way.
       */
      ASN1_INTEGER_free(p7i->issuer_and_serial->serial);
      if (!(p7i->issuer_and_serial->serial =
            ASN1_INTEGER_dup(X509_get0_serialNumber(x509))))
          return 0;
  
      /* lets keep the pkey around for a while */
      EVP_PKEY_up_ref(pkey);
      p7i->pkey = pkey;
  
      /* Set the algorithms */
  
      if (!X509_ALGOR_set0(p7i->digest_alg, OBJ_nid2obj(EVP_MD_get_type(dgst)),
                           V_ASN1_NULL, NULL))
          return 0;
  
      if (EVP_PKEY_is_a(pkey, "EC") || EVP_PKEY_is_a(pkey, "DSA"))
          return pkcs7_ecdsa_or_dsa_sign_verify_setup(p7i, 0);
      if (EVP_PKEY_is_a(pkey, "RSA"))
          return pkcs7_rsa_sign_verify_setup(p7i, 0);
  
      if (pkey->ameth != NULL && pkey->ameth->pkey_ctrl != NULL) {
          ret = pkey->ameth->pkey_ctrl(pkey, ASN1_PKEY_CTRL_PKCS7_SIGN, 0, p7i);
          if (ret > 0)
              return 1;
          if (ret != -2) {
              ERR_raise(ERR_LIB_PKCS7, PKCS7_R_SIGNING_CTRL_FAILURE);
              return 0;
          }
      }
      ERR_raise(ERR_LIB_PKCS7, PKCS7_R_SIGNING_NOT_SUPPORTED_FOR_THIS_KEY_TYPE);
      return 0;
  }
  
  PKCS7_SIGNER_INFO *PKCS7_add_signature(PKCS7 *p7, X509 *x509, EVP_PKEY *pkey,
                                         const EVP_MD *dgst)
  {
      PKCS7_SIGNER_INFO *si = NULL;
  
      if (dgst == NULL) {
          int def_nid;
          if (EVP_PKEY_get_default_digest_nid(pkey, &def_nid) <= 0)
              goto err;
          dgst = EVP_get_digestbynid(def_nid);
          if (dgst == NULL) {
              ERR_raise(ERR_LIB_PKCS7, PKCS7_R_NO_DEFAULT_DIGEST);
              goto err;
          }
      }
  
      if ((si = PKCS7_SIGNER_INFO_new()) == NULL)
          goto err;
      if (!PKCS7_SIGNER_INFO_set(si, x509, pkey, dgst))
          goto err;
      if (!PKCS7_add_signer(p7, si))
          goto err;
      return si;
   err:
      PKCS7_SIGNER_INFO_free(si);
      return NULL;
  }
  
  static STACK_OF(X509) *pkcs7_get_signer_certs(const PKCS7 *p7)
  {
      if (PKCS7_type_is_signed(p7))
          return p7->d.sign->cert;
      if (PKCS7_type_is_signedAndEnveloped(p7))
          return p7->d.signed_and_enveloped->cert;
      return NULL;
  }
  
  static STACK_OF(PKCS7_RECIP_INFO) *pkcs7_get_recipient_info(const PKCS7 *p7)
  {
      if (PKCS7_type_is_signedAndEnveloped(p7))
          return p7->d.signed_and_enveloped->recipientinfo;
      if (PKCS7_type_is_enveloped(p7))
          return p7->d.enveloped->recipientinfo;
      return NULL;
  }
  
  /*
   * Set up the library context into any loaded structure that needs it.
   * i.e loaded X509 objects.
   */
  void ossl_pkcs7_resolve_libctx(PKCS7 *p7)
  {
      int i;
      const PKCS7_CTX *ctx = ossl_pkcs7_get0_ctx(p7);
      OSSL_LIB_CTX *libctx = ossl_pkcs7_ctx_get0_libctx(ctx);
      const char *propq = ossl_pkcs7_ctx_get0_propq(ctx);
      STACK_OF(PKCS7_RECIP_INFO) *rinfos = pkcs7_get_recipient_info(p7);
      STACK_OF(PKCS7_SIGNER_INFO) *sinfos = PKCS7_get_signer_info(p7);
      STACK_OF(X509) *certs = pkcs7_get_signer_certs(p7);
  
      if (ctx == NULL)
          return;
  
      for (i = 0; i < sk_X509_num(certs); i++)
          ossl_x509_set0_libctx(sk_X509_value(certs, i), libctx, propq);
  
      for (i = 0; i < sk_PKCS7_RECIP_INFO_num(rinfos); i++) {
          PKCS7_RECIP_INFO *ri = sk_PKCS7_RECIP_INFO_value(rinfos, i);
  
          ossl_x509_set0_libctx(ri->cert, libctx, propq);
      }
  
      for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
          PKCS7_SIGNER_INFO *si = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
  
          if (si != NULL)
              si->ctx = ctx;
      }
  }
  
  const PKCS7_CTX *ossl_pkcs7_get0_ctx(const PKCS7 *p7)
  {
      return p7 != NULL ? &p7->ctx : NULL;
  }
  
  void ossl_pkcs7_set0_libctx(PKCS7 *p7, OSSL_LIB_CTX *ctx)
  {
      p7->ctx.libctx = ctx;
  }
  
  int ossl_pkcs7_set1_propq(PKCS7 *p7, const char *propq)
  {
      if (p7->ctx.propq != NULL) {
          OPENSSL_free(p7->ctx.propq);
          p7->ctx.propq = NULL;
      }
      if (propq != NULL) {
          p7->ctx.propq = OPENSSL_strdup(propq);
          if (p7->ctx.propq == NULL) {
              ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
              return 0;
          }
      }
      return 1;
  }
  
  int ossl_pkcs7_ctx_propagate(const PKCS7 *from, PKCS7 *to)
  {
      ossl_pkcs7_set0_libctx(to, from->ctx.libctx);
      if (!ossl_pkcs7_set1_propq(to, from->ctx.propq))
          return 0;
  
      ossl_pkcs7_resolve_libctx(to);
      return 1;
  }
  
  OSSL_LIB_CTX *ossl_pkcs7_ctx_get0_libctx(const PKCS7_CTX *ctx)
  {
      return ctx != NULL ? ctx->libctx : NULL;
  }
  const char *ossl_pkcs7_ctx_get0_propq(const PKCS7_CTX *ctx)
  {
      return ctx != NULL ? ctx->propq : NULL;
  }
  
  int PKCS7_set_digest(PKCS7 *p7, const EVP_MD *md)
  {
      if (PKCS7_type_is_digest(p7)) {
          if ((p7->d.digest->md->parameter = ASN1_TYPE_new()) == NULL) {
              ERR_raise(ERR_LIB_PKCS7, ERR_R_MALLOC_FAILURE);
              return 0;
          }
          p7->d.digest->md->parameter->type = V_ASN1_NULL;
          p7->d.digest->md->algorithm = OBJ_nid2obj(EVP_MD_nid(md));
          return 1;
      }
  
      ERR_raise(ERR_LIB_PKCS7, PKCS7_R_WRONG_CONTENT_TYPE);
      return 1;
  }
  
  STACK_OF(PKCS7_SIGNER_INFO) *PKCS7_get_signer_info(PKCS7 *p7)
  {
      if (p7 == NULL || p7->d.ptr == NULL)
          return NULL;
      if (PKCS7_type_is_signed(p7)) {
          return p7->d.sign->signer_info;
      } else if (PKCS7_type_is_signedAndEnveloped(p7)) {
          return p7->d.signed_and_enveloped->signer_info;
      } else
          return NULL;
  }
  
  void PKCS7_SIGNER_INFO_get0_algs(PKCS7_SIGNER_INFO *si, EVP_PKEY **pk,
                                   X509_ALGOR **pdig, X509_ALGOR **psig)
  {
      if (pk)
          *pk = si->pkey;
      if (pdig)
          *pdig = si->digest_alg;
      if (psig)
          *psig = si->digest_enc_alg;
  }
  
  void PKCS7_RECIP_INFO_get0_alg(PKCS7_RECIP_INFO *ri, X509_ALGOR **penc)
  {
      if (penc)
          *penc = ri->key_enc_algor;
  }
  
  PKCS7_RECIP_INFO *PKCS7_add_recipient(PKCS7 *p7, X509 *x509)
  {
      PKCS7_RECIP_INFO *ri;
  
      if ((ri = PKCS7_RECIP_INFO_new()) == NULL)
          goto err;
      if (!PKCS7_RECIP_INFO_set(ri, x509))
          goto err;
      if (!PKCS7_add_recipient_info(p7, ri))
          goto err;
      ri->ctx = ossl_pkcs7_get0_ctx(p7);
      return ri;
   err:
      PKCS7_RECIP_INFO_free(ri);
      return NULL;
  }
  
  int PKCS7_add_recipient_info(PKCS7 *p7, PKCS7_RECIP_INFO *ri)
  {
      int i;
      STACK_OF(PKCS7_RECIP_INFO) *sk;
  
      i = OBJ_obj2nid(p7->type);
      switch (i) {
      case NID_pkcs7_signedAndEnveloped:
          sk = p7->d.signed_and_enveloped->recipientinfo;
          break;
      case NID_pkcs7_enveloped:
          sk = p7->d.enveloped->recipientinfo;
          break;
      default:
          ERR_raise(ERR_LIB_PKCS7, PKCS7_R_WRONG_CONTENT_TYPE);
          return 0;
      }
  
      if (!sk_PKCS7_RECIP_INFO_push(sk, ri))
          return 0;
      return 1;
  }
  
  static int pkcs7_rsa_encrypt_decrypt_setup(PKCS7_RECIP_INFO *ri, int decrypt)
  {
      X509_ALGOR *alg = NULL;
  
      if (!decrypt) {
          PKCS7_RECIP_INFO_get0_alg(ri, &alg);
          if (alg != NULL)
              return X509_ALGOR_set0(alg, OBJ_nid2obj(NID_rsaEncryption),
                                     V_ASN1_NULL, NULL);
      }
      return 1;
  }
  
  int PKCS7_RECIP_INFO_set(PKCS7_RECIP_INFO *p7i, X509 *x509)
  {
      int ret;
      EVP_PKEY *pkey = NULL;
      if (!ASN1_INTEGER_set(p7i->version, 0))
          return 0;
      if (!X509_NAME_set(&p7i->issuer_and_serial->issuer,
                         X509_get_issuer_name(x509)))
          return 0;
  
      ASN1_INTEGER_free(p7i->issuer_and_serial->serial);
      if (!(p7i->issuer_and_serial->serial =
            ASN1_INTEGER_dup(X509_get0_serialNumber(x509))))
          return 0;
  
      pkey = X509_get0_pubkey(x509);
      if (pkey == NULL)
          return 0;
  
      if (EVP_PKEY_is_a(pkey, "RSA-PSS"))
          return -2;
      if (EVP_PKEY_is_a(pkey, "RSA")) {
          if (pkcs7_rsa_encrypt_decrypt_setup(p7i, 0) <= 0)
              goto err;
          goto finished;
      }
  
      if (pkey->ameth == NULL || pkey->ameth->pkey_ctrl == NULL) {
          ERR_raise(ERR_LIB_PKCS7,
                    PKCS7_R_ENCRYPTION_NOT_SUPPORTED_FOR_THIS_KEY_TYPE);
          goto err;
      }
  
      ret = pkey->ameth->pkey_ctrl(pkey, ASN1_PKEY_CTRL_PKCS7_ENCRYPT, 0, p7i);
      if (ret == -2) {
          ERR_raise(ERR_LIB_PKCS7,
                    PKCS7_R_ENCRYPTION_NOT_SUPPORTED_FOR_THIS_KEY_TYPE);
          goto err;
      }
      if (ret <= 0) {
          ERR_raise(ERR_LIB_PKCS7, PKCS7_R_ENCRYPTION_CTRL_FAILURE);
          goto err;
      }
  finished:
      X509_up_ref(x509);
      p7i->cert = x509;
  
      return 1;
  
   err:
      return 0;
  }
  
  X509 *PKCS7_cert_from_signer_info(PKCS7 *p7, PKCS7_SIGNER_INFO *si)
  {
      if (PKCS7_type_is_signed(p7))
          return (X509_find_by_issuer_and_serial(p7->d.sign->cert,
                                                 si->issuer_and_serial->issuer,
                                                 si->
                                                 issuer_and_serial->serial));
      else
          return NULL;
  }
  
  int PKCS7_set_cipher(PKCS7 *p7, const EVP_CIPHER *cipher)
  {
      int i;
      PKCS7_ENC_CONTENT *ec;
  
      i = OBJ_obj2nid(p7->type);
      switch (i) {
      case NID_pkcs7_signedAndEnveloped:
          ec = p7->d.signed_and_enveloped->enc_data;
          break;
      case NID_pkcs7_enveloped:
          ec = p7->d.enveloped->enc_data;
          break;
      default:
          ERR_raise(ERR_LIB_PKCS7, PKCS7_R_WRONG_CONTENT_TYPE);
          return 0;
      }
  
      /* Check cipher OID exists and has data in it */
      i = EVP_CIPHER_get_type(cipher);
      if (i == NID_undef) {
          ERR_raise(ERR_LIB_PKCS7, PKCS7_R_CIPHER_HAS_NO_OBJECT_IDENTIFIER);
          return 0;
      }
  
      ec->cipher = cipher;
      ec->ctx = ossl_pkcs7_get0_ctx(p7);
      return 1;
  }
  
  /* unfortunately cannot constify BIO_new_NDEF() due to this and CMS_stream() */
  int PKCS7_stream(unsigned char ***boundary, PKCS7 *p7)
  {
      ASN1_OCTET_STRING *os = NULL;
  
      switch (OBJ_obj2nid(p7->type)) {
      case NID_pkcs7_data:
          os = p7->d.data;
          break;
  
      case NID_pkcs7_signedAndEnveloped:
          os = p7->d.signed_and_enveloped->enc_data->enc_data;
          if (os == NULL) {
              os = ASN1_OCTET_STRING_new();
              p7->d.signed_and_enveloped->enc_data->enc_data = os;
          }
          break;
  
      case NID_pkcs7_enveloped:
          os = p7->d.enveloped->enc_data->enc_data;
          if (os == NULL) {
              os = ASN1_OCTET_STRING_new();
              p7->d.enveloped->enc_data->enc_data = os;
          }
          break;
  
      case NID_pkcs7_signed:
          os = p7->d.sign->contents->d.data;
          break;
  
      default:
          os = NULL;
          break;
      }
  
      if (os == NULL)
          return 0;
  
      os->flags |= ASN1_STRING_FLAG_NDEF;
      *boundary = &os->data;
  
      return 1;
  }
  