pkcs7: add function to display signature information

Basically export print_pkcs7_info() in a way usable by external
applications.

Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com>

3 files changed, 36 insertions, 0 deletions

diff --git a/lib/includes/gnutls/pkcs7.h b/lib/includes/gnutls/pkcs7.h
index 8a6c2034f0..58ea4aaf81 100644
--- a/lib/includes/gnutls/pkcs7.h
+++ b/lib/includes/gnutls/pkcs7.h
@@ -144,6 +144,10 @@ int gnutls_pkcs7_print(gnutls_pkcs7_t pkcs7,
 		       gnutls_certificate_print_formats_t format,
 		       gnutls_datum_t * out);
 
+int gnutls_pkcs7_print_signature_info(gnutls_pkcs7_signature_info_st * info,
+				      gnutls_certificate_print_formats_t format,
+				      gnutls_datum_t * out);
+
 /* *INDENT-OFF* */
 #ifdef __cplusplus
 }
diff --git a/lib/libgnutls.map b/lib/libgnutls.map
index 512e403bb6..ac6be479f1 100644
--- a/lib/libgnutls.map
+++ b/lib/libgnutls.map
@@ -1328,6 +1328,7 @@ GNUTLS_3_6_14
 {
  global:
 	gnutls_ext_get_name2;
+	gnutls_pkcs7_print_signature_info;
 } GNUTLS_3_6_13;
 
 GNUTLS_FIPS140_3_4 {
diff --git a/lib/x509/pkcs7-output.c b/lib/x509/pkcs7-output.c
index bcffbaafd5..3d686df228 100644
--- a/lib/x509/pkcs7-output.c
+++ b/lib/x509/pkcs7-output.c
@@ -185,6 +185,37 @@ static void print_pkcs7_info(gnutls_pkcs7_signature_info_st * info,
 }
 
 /**
+ * gnutls_pkcs7_print_signature_info:
+ * @info: The PKCS7 signature info struct to be printed
+ * @format: Indicate the format to use
+ * @out: Newly allocated datum with null terminated string.
+ *
+ * This function will pretty print a PKCS #7 signature info structure, suitable
+ * for display to a human.
+ *
+ * Currently the supported formats are %GNUTLS_CRT_PRINT_FULL and
+ * %GNUTLS_CRT_PRINT_COMPACT.
+ *
+ * The output @out needs to be deallocated using gnutls_free().
+ *
+ * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned, otherwise a
+ *   negative error value.
+ *
+ * Since: 3.6.14
+ **/
+int gnutls_pkcs7_print_signature_info(gnutls_pkcs7_signature_info_st * info,
+				      gnutls_certificate_print_formats_t format,
+				      gnutls_datum_t * out)
+{
+	gnutls_buffer_st str;
+
+	_gnutls_buffer_init(&str);
+	print_pkcs7_info(info, &str, format);
+
+	return _gnutls_buffer_to_datum(&str, out, 1);
+}
+
+/**
  * gnutls_pkcs7_crt_print:
  * @pkcs7: The PKCS7 struct to be printed
  * @format: Indicate the format to use