+/*
+ * We only support signed data [RFC2315 sec 9].
+ */
+int pkcs7_check_content_type(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+
+ if (ctx->last_oid != OID_signed_data) {
+ pr_warn("Only support pkcs7_signedData type\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/*
+ * Note the SignedData version
+ */
+int pkcs7_note_signeddata_version(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+ unsigned version;
+
+ if (vlen != 1)
+ goto unsupported;
+
+ ctx->msg->version = version = *(const u8 *)value;
+ switch (version) {
+ case 1:
+ /* PKCS#7 SignedData [RFC2315 sec 9.1]
+ * CMS ver 1 SignedData [RFC5652 sec 5.1]
+ */
+ break;
+ case 3:
+ /* CMS ver 3 SignedData [RFC2315 sec 5.1] */
+ break;
+ default:
+ goto unsupported;
+ }
+
+ return 0;
+
+unsupported:
+ pr_warn("Unsupported SignedData version\n");
+ return -EINVAL;
+}
+
+/*
+ * Note the SignerInfo version
+ */
+int pkcs7_note_signerinfo_version(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct pkcs7_parse_context *ctx = context;
+ unsigned version;
+
+ if (vlen != 1)
+ goto unsupported;
+
+ version = *(const u8 *)value;
+ switch (version) {
+ case 1:
+ /* PKCS#7 SignerInfo [RFC2315 sec 9.2]
+ * CMS ver 1 SignerInfo [RFC5652 sec 5.3]
+ */
+ if (ctx->msg->version != 1)
+ goto version_mismatch;
+ ctx->expect_skid = false;
+ break;
+ case 3:
+ /* CMS ver 3 SignerInfo [RFC2315 sec 5.3] */
+ if (ctx->msg->version == 1)
+ goto version_mismatch;
+ ctx->expect_skid = true;
+ break;
+ default:
+ goto unsupported;
+ }
+
+ return 0;
+
+unsupported:
+ pr_warn("Unsupported SignerInfo version\n");
+ return -EINVAL;
+version_mismatch:
+ pr_warn("SignedData-SignerInfo version mismatch\n");
+ return -EBADMSG;
+}
+