CMS: Export CMS_EnvelopedData and add CMS_EnvelopedData_decrypt()

Also document CMS_decrypt_set1_password() and fix CMS_EnvelopedData_create.pod.

Reviewed-by: Dmitry Belyavskiy <beldmit@gmail.com>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: David von Oheimb <david.von.oheimb@siemens.com>
(Merged from https://github.com/openssl/openssl/pull/18301)

2 files changed, 37 insertions, 1 deletions

diff --git a/crypto/cms/cms_env.c b/crypto/cms/cms_env.c
index 24632fa9c1..471676d2f5 100644
--- a/crypto/cms/cms_env.c
+++ b/crypto/cms/cms_env.c
@@ -242,6 +242,43 @@ CMS_ContentInfo *CMS_EnvelopedData_create(const EVP_CIPHER *cipher)
     return CMS_EnvelopedData_create_ex(cipher, NULL, NULL);
 }
 
+BIO *CMS_EnvelopedData_decrypt(CMS_EnvelopedData *env, BIO *detached_data,
+                               EVP_PKEY *pkey, X509 *cert,
+                               ASN1_OCTET_STRING *secret, unsigned int flags,
+                               OSSL_LIB_CTX *libctx, const char *propq)
+{
+    CMS_ContentInfo *ci;
+    BIO *bio = NULL;
+    int res = 0;
+
+    if (env == NULL) {
+        ERR_raise(ERR_LIB_CMS, ERR_R_PASSED_NULL_PARAMETER);
+        return NULL;
+    }
+
+    if ((ci = CMS_ContentInfo_new_ex(libctx, propq)) == NULL
+            || (bio = BIO_new(BIO_s_mem())) == NULL)
+        goto end;
+    ci->contentType = OBJ_nid2obj(NID_pkcs7_enveloped);
+    ci->d.envelopedData = env;
+    if (secret != NULL
+        && CMS_decrypt_set1_password(ci, (unsigned char *)
+                                     ASN1_STRING_get0_data(secret),
+                                     ASN1_STRING_length(secret)) != 1)
+        goto end;
+    res = CMS_decrypt(ci, pkey, cert, detached_data, bio, flags);
+
+ end:
+    if (ci != NULL)
+        ci->d.envelopedData = NULL;
+    CMS_ContentInfo_free(ci);
+    if (!res) {
+        BIO_free(bio);
+        bio = NULL;
+    }
+    return bio;
+}
+
 CMS_ContentInfo *
 CMS_AuthEnvelopedData_create_ex(const EVP_CIPHER *cipher, OSSL_LIB_CTX *libctx,
                                 const char *propq)
diff --git a/crypto/cms/cms_local.h b/crypto/cms/cms_local.h
index 096235c0fa..d16ca95176 100644
--- a/crypto/cms/cms_local.h
+++ b/crypto/cms/cms_local.h
@@ -25,7 +25,6 @@ typedef struct CMS_SignedData_st CMS_SignedData;
 typedef struct CMS_OtherRevocationInfoFormat_st CMS_OtherRevocationInfoFormat;
 typedef struct CMS_OriginatorInfo_st CMS_OriginatorInfo;
 typedef struct CMS_EncryptedContentInfo_st CMS_EncryptedContentInfo;
-typedef struct CMS_EnvelopedData_st CMS_EnvelopedData;
 typedef struct CMS_DigestedData_st CMS_DigestedData;
 typedef struct CMS_EncryptedData_st CMS_EncryptedData;
 typedef struct CMS_AuthenticatedData_st CMS_AuthenticatedData;