x509/output: print the public key PIN of a certificate

That is, print the value used by the HPKP protocol as per
RFC7469.

Signed-off-by: Nikos Mavrogiannopoulos <nmav@redhat.com>

3 files changed, 27 insertions, 0 deletions

diff --git a/lib/str.c b/lib/str.c
index 647b03c836..673caa9e7d 100644
--- a/lib/str.c
+++ b/lib/str.c
@@ -27,6 +27,7 @@
 #include <stdarg.h>
 #include <c-ctype.h>
 #include <intprops.h>
+#include <nettle/base64.h>
 #include "vasprintf.h"
 #include "extras/hex.h"
 
@@ -918,6 +919,26 @@ _gnutls_buffer_hexprint(gnutls_buffer_st * str,
 	}
 }
 
+int
+_gnutls_buffer_base64print(gnutls_buffer_st * str,
+			   const void *_data, size_t len)
+{
+	const unsigned char *data = _data;
+	unsigned b64len = BASE64_ENCODE_RAW_LENGTH(len);
+	int ret;
+
+	ret = _gnutls_buffer_resize(str, str->length+b64len+1);
+	if (ret < 0) {
+		return gnutls_assert_val(ret);
+	}
+
+	base64_encode_raw(&str->data[str->length], len, data);
+	str->length += b64len;
+	str->data[str->length] = 0;
+
+	return 0;
+}
+
 void
 _gnutls_buffer_hexdump(gnutls_buffer_st * str, const void *_data,
 		       size_t len, const char *spc)
diff --git a/lib/str.h b/lib/str.h
index d67fec4162..b40202eb5c 100644
--- a/lib/str.h
+++ b/lib/str.h
@@ -134,6 +134,8 @@ int _gnutls_buffer_append_printf(gnutls_buffer_st * dest, const char *fmt,
 
 void _gnutls_buffer_hexprint(gnutls_buffer_st * str,
 			     const void *data, size_t len);
+int _gnutls_buffer_base64print(gnutls_buffer_st * str,
+			        const void *data, size_t len);
 void _gnutls_buffer_hexdump(gnutls_buffer_st * str, const void *data,
 			    size_t len, const char *spc);
 void _gnutls_buffer_asciiprint(gnutls_buffer_st * str,
diff --git a/lib/x509/output.c b/lib/x509/output.c
index 642d74d070..2eca0b99cf 100644
--- a/lib/x509/output.c
+++ b/lib/x509/output.c
@@ -1629,6 +1629,10 @@ static void print_obj_id(gnutls_buffer_st *str, const char *prefix, void *obj, g
 	_gnutls_buffer_hexprint(str, sha2_buffer, sha2_size);
 	adds(str, "\n");
 
+	addf(str, _("%sPublic Key PIN:\n%s\tpin-sha256:"), prefix, prefix);
+	_gnutls_buffer_base64print(str, sha2_buffer, sha2_size);
+	adds(str, "\n");
+
 	return;
 }