1 files changed, 53 insertions, 1 deletions

diff --git a/common/pem.c b/common/pem.c
index 3d3d284..b3c6acd 100644
--- a/common/pem.c
+++ b/common/pem.c
@@ -36,6 +36,7 @@
 
 #include "compat.h"
 #include "base64.h"
+#include "buffer.h"
 #include "debug.h"
 #include "pem.h"
 
@@ -119,7 +120,7 @@ pem_find_end (const char *data,
 	data += n_type;
 
 	/* Next comes the suffix */
-	if (ARMOR_SUFF_L > n_data && strncmp ((char *)data, ARMOR_SUFF, ARMOR_SUFF_L) != 0)
+	if (ARMOR_SUFF_L > n_data || strncmp ((char *)data, ARMOR_SUFF, ARMOR_SUFF_L) != 0)
 		return NULL;
 
 	/* The end of the data */
@@ -239,3 +240,54 @@ p11_pem_parse (const char *data,
 
 	return nfound;
 }
+
+char *
+p11_pem_write (const unsigned char *contents,
+               size_t length,
+               const char *type,
+               size_t *pem_len)
+{
+	p11_buffer buffer;
+	size_t estimate;
+	size_t prefix;
+	char *target;
+	int len;
+
+	return_val_if_fail (contents || !length, NULL);
+	return_val_if_fail (type, NULL);
+	return_val_if_fail (pem_len, NULL);
+
+	/* Estimate from base64 data. Algorithm from Glib reference */
+	estimate = length * 4 / 3 + 7;
+	estimate += estimate / 64 + 1;
+
+	if (!p11_buffer_init_null (&buffer, estimate + 128))
+		return_val_if_reached (NULL);
+
+	p11_buffer_add (&buffer, ARMOR_PREF_BEGIN, ARMOR_PREF_BEGIN_L);
+	p11_buffer_add (&buffer, type, -1);
+	p11_buffer_add (&buffer, ARMOR_SUFF, ARMOR_SUFF_L);
+
+	prefix = buffer.len;
+	target = p11_buffer_append (&buffer, estimate);
+	return_val_if_fail (target != NULL, NULL);
+
+	/*
+	 * OpenSSL is absolutely certain that it wants its PEM base64
+	 * lines to be 64 characters in len.
+	 */
+
+	len = p11_b64_ntop (contents, length, target, estimate, 64);
+
+	assert (len > 0);
+	assert (len <= estimate);
+	buffer.len = prefix + len;
+
+	p11_buffer_add (&buffer, "\n", 1);
+	p11_buffer_add (&buffer, ARMOR_PREF_END, ARMOR_PREF_END_L);
+	p11_buffer_add (&buffer, type, -1);
+	p11_buffer_add (&buffer, ARMOR_SUFF, ARMOR_SUFF_L);
+	p11_buffer_add (&buffer, "\n", 1);
+
+	return p11_buffer_steal (&buffer, pem_len);
+}