+/* Digest a SignerInfo structure for msgSigDigest attribute processing */
+
+static int cms_msgSigDigest(CMS_SignerInfo *si,
+ unsigned char *dig, unsigned int *diglen)
+ {
+ const EVP_MD *md;
+ md = EVP_get_digestbyobj(si->digestAlgorithm->algorithm);
+ if (md == NULL)
+ return 0;
+ if (!ASN1_item_digest(ASN1_ITEM_rptr(CMS_Attributes_Verify), md,
+ si->signedAttrs, dig, diglen))
+ return 0;
+ return 1;
+ }
+
+/* Add a msgSigDigest attribute to a SignerInfo */
+
+int cms_msgSigDigest_add1(CMS_SignerInfo *dest, CMS_SignerInfo *src)
+ {
+ unsigned char dig[EVP_MAX_MD_SIZE];
+ unsigned int diglen;
+ if (!cms_msgSigDigest(src, dig, &diglen))
+ {
+ CMSerr(CMS_F_CMS_MSGSIGDIGEST_ADD1, CMS_R_MSGSIGDIGEST_ERROR);
+ return 0;
+ }
+ if (!CMS_signed_add1_attr_by_NID(dest, NID_id_smime_aa_msgSigDigest,
+ V_ASN1_OCTET_STRING, dig, diglen))
+ {
+ CMSerr(CMS_F_CMS_MSGSIGDIGEST_ADD1, ERR_R_MALLOC_FAILURE);
+ return 0;
+ }
+ return 1;
+ }
+
+/* Verify signed receipt after it has already passed normal CMS verify */
+
+int cms_Receipt_verify(CMS_ContentInfo *cms, CMS_ContentInfo *req_cms)
+ {
+ int r = 0, i;
+ CMS_ReceiptRequest *rr = NULL;
+ CMS_Receipt *rct = NULL;
+ STACK_OF(CMS_SignerInfo) *sis, *osis;
+ CMS_SignerInfo *si, *osi = NULL;
+ ASN1_OCTET_STRING *msig, **pcont;
+ ASN1_OBJECT *octype;
+ unsigned char dig[EVP_MAX_MD_SIZE];
+ unsigned int diglen;
+
+ /* Get SignerInfos, also checks SignedData content type */
+ osis = CMS_get0_SignerInfos(req_cms);
+ sis = CMS_get0_SignerInfos(cms);
+ if (!osis || !sis)
+ goto err;
+
+ if (sk_CMS_SignerInfo_num(sis) != 1)
+ {
+ CMSerr(CMS_F_CMS_RECEIPT_VERIFY, CMS_R_NEED_ONE_SIGNER);
+ goto err;
+ }
+
+ /* Check receipt content type */
+ if (OBJ_obj2nid(CMS_get0_eContentType(cms)) != NID_id_smime_ct_receipt)
+ {
+ CMSerr(CMS_F_CMS_RECEIPT_VERIFY, CMS_R_NOT_A_SIGNED_RECEIPT);
+ goto err;
+ }
+
+ /* Extract and decode receipt content */
+ pcont = CMS_get0_content(cms);
+ if (!pcont || !*pcont)
+ {
+ CMSerr(CMS_F_CMS_RECEIPT_VERIFY, CMS_R_NO_CONTENT);
+ goto err;
+ }
+
+ rct = ASN1_item_unpack(*pcont, ASN1_ITEM_rptr(CMS_Receipt));
+
+ if (!rct)
+ {
+ CMSerr(CMS_F_CMS_RECEIPT_VERIFY, CMS_R_RECEIPT_DECODE_ERROR);
+ goto err;
+ }
+
+ /* Locate original request */
+
+ for (i = 0; i < sk_CMS_SignerInfo_num(osis); i++)
+ {
+ osi = sk_CMS_SignerInfo_value(osis, i);
+ if (!ASN1_STRING_cmp(osi->signature,
+ rct->originatorSignatureValue))
+ break;
+ }
+
+ if (i == sk_CMS_SignerInfo_num(osis))
+ {
+ CMSerr(CMS_F_CMS_RECEIPT_VERIFY, CMS_R_NO_MATCHING_SIGNATURE);
+ goto err;
+ }
+
+ si = sk_CMS_SignerInfo_value(sis, 0);
+
+ /* Get msgSigDigest value and compare */
+
+ msig = CMS_signed_get0_data_by_OBJ(si,
+ OBJ_nid2obj(NID_id_smime_aa_msgSigDigest),
+ -3, V_ASN1_OCTET_STRING);
+
+ if (!msig)
+ {
+ CMSerr(CMS_F_CMS_RECEIPT_VERIFY, CMS_R_NO_MSGSIGDIGEST);
+ goto err;
+ }
+
+ if (!cms_msgSigDigest(osi, dig, &diglen))
+ {
+ CMSerr(CMS_F_CMS_RECEIPT_VERIFY, CMS_R_MSGSIGDIGEST_ERROR);
+ goto err;
+ }
+
+ if (diglen != (unsigned int)msig->length)
+ {
+ CMSerr(CMS_F_CMS_RECEIPT_VERIFY,
+ CMS_R_MSGSIGDIGEST_WRONG_LENGTH);
+ goto err;
+ }
+
+ if (memcmp(dig, msig->data, diglen))
+ {
+ CMSerr(CMS_F_CMS_RECEIPT_VERIFY,
+ CMS_R_MSGSIGDIGEST_VERIFICATION_FAILURE);
+ goto err;
+ }
+
+ /* Compare content types */
+
+ octype = CMS_signed_get0_data_by_OBJ(osi,
+ OBJ_nid2obj(NID_pkcs9_contentType),
+ -3, V_ASN1_OBJECT);
+ if (!octype)
+ {
+ CMSerr(CMS_F_CMS_RECEIPT_VERIFY, CMS_R_NO_CONTENT_TYPE);
+ goto err;
+ }
+
+ /* Compare details in receipt request */
+
+ if (OBJ_cmp(octype, rct->contentType))
+ {
+ CMSerr(CMS_F_CMS_RECEIPT_VERIFY, CMS_R_CONTENT_TYPE_MISMATCH);
+ goto err;
+ }
+
+ /* Get original receipt request details */
+
+ if (CMS_get1_ReceiptRequest(osi, &rr) <= 0)
+ {
+ CMSerr(CMS_F_CMS_RECEIPT_VERIFY, CMS_R_NO_RECEIPT_REQUEST);
+ goto err;
+ }
+
+ if (ASN1_STRING_cmp(rr->signedContentIdentifier,
+ rct->signedContentIdentifier))
+ {
+ CMSerr(CMS_F_CMS_RECEIPT_VERIFY,
+ CMS_R_CONTENTIDENTIFIER_MISMATCH);
+ goto err;
+ }
+
+ r = 1;
+
+ err:
+ if (rr)
+ CMS_ReceiptRequest_free(rr);
+ if (rct)
+ M_ASN1_free_of(rct, CMS_Receipt);
+
+ return r;
+
+ }
+
+/* Encode a Receipt into an OCTET STRING read for including into content of
+ * a SignedData ContentInfo.
+ */
+
+ASN1_OCTET_STRING *cms_encode_Receipt(CMS_SignerInfo *si)
+ {
+ CMS_Receipt rct;
+ CMS_ReceiptRequest *rr = NULL;
+ ASN1_OBJECT *ctype;
+ ASN1_OCTET_STRING *os = NULL;
+
+ /* Get original receipt request */
+
+ /* Get original receipt request details */
+
+ if (CMS_get1_ReceiptRequest(si, &rr) <= 0)
+ {
+ CMSerr(CMS_F_CMS_ENCODE_RECEIPT, CMS_R_NO_RECEIPT_REQUEST);
+ goto err;
+ }
+
+ /* Get original content type */
+
+ ctype = CMS_signed_get0_data_by_OBJ(si,
+ OBJ_nid2obj(NID_pkcs9_contentType),
+ -3, V_ASN1_OBJECT);
+ if (!ctype)
+ {
+ CMSerr(CMS_F_CMS_ENCODE_RECEIPT, CMS_R_NO_CONTENT_TYPE);
+ goto err;
+ }
+
+ rct.version = 1;
+ rct.contentType = ctype;
+ rct.signedContentIdentifier = rr->signedContentIdentifier;
+ rct.originatorSignatureValue = si->signature;
+
+ os = ASN1_item_pack(&rct, ASN1_ITEM_rptr(CMS_Receipt), NULL);
+
+ err:
+ if (rr)
+ CMS_ReceiptRequest_free(rr);
+
+ return os;
+
+ }