1 files changed, 82 insertions, 0 deletions
diff --git a/contrib/pgcrypto/crypt-gensalt.c b/contrib/pgcrypto/crypt-gensalt.c
index 740f3612532..ef68ae0e49e 100644
--- a/contrib/pgcrypto/crypt-gensalt.c
+++ b/contrib/pgcrypto/crypt-gensalt.c
@@ -185,3 +185,85 @@ _crypt_gensalt_blowfish_rn(unsigned long count,
 
 	return output;
 }
+
+/*
+ * Helper for _crypt_gensalt_sha256_rn and _crypt_gensalt_sha512_rn
+ */
+static char *
+_crypt_gensalt_sha(unsigned long count,
+				   const char *input, int size, char *output, int output_size)
+{
+	char	   *s_ptr = output;
+	unsigned int result_bufsize = PX_SHACRYPT_SALT_BUF_LEN;
+	int			rc;
+
+	/* output buffer must be allocated with PX_MAX_SALT_LEN bytes */
+	if (PX_MAX_SALT_LEN < result_bufsize)
+		ereport(ERROR,
+				errcode(ERRCODE_SYNTAX_ERROR),
+				errmsg("invalid size of salt"));
+
+	/*
+	 * Care must be taken to not exceed the buffer size allocated for the
+	 * input character buffer.
+	 */
+	if ((PX_SHACRYPT_SALT_MAX_LEN != size) || (output_size < size))
+		ereport(ERROR,
+				errcode(ERRCODE_INTERNAL_ERROR),
+				errmsg("invalid length of salt buffer"));
+
+	/* Skip magic bytes, set by callers */
+	s_ptr += 3;
+	if ((rc = pg_snprintf(s_ptr, 18, "rounds=%ld$", count)) <= 0)
+		ereport(ERROR,
+				errcode(ERRCODE_INTERNAL_ERROR),
+				errmsg("cannot format salt string"));
+
+	/* s_ptr should now be positioned at the start of the salt string */
+	s_ptr += rc;
+
+	/*
+	 * Normalize salt string
+	 *
+	 * size of input buffer was checked above to not exceed
+	 * PX_SHACRYPT_SALT_LEN_MAX.
+	 */
+	for (int i = 0; i < size; i++)
+	{
+		*s_ptr = _crypt_itoa64[input[i] & 0x3f];
+		s_ptr++;
+	}
+
+	/* We're done */
+	return output;
+}
+
+/* gen_list->gen function for sha512 */
+char *
+_crypt_gensalt_sha512_rn(unsigned long count,
+						 char const *input, int size,
+						 char *output, int output_size)
+{
+	memset(output, 0, output_size);
+	/* set magic byte for sha512crypt */
+	output[0] = '$';
+	output[1] = '6';
+	output[2] = '$';
+
+	return _crypt_gensalt_sha(count, input, size, output, output_size);
+}
+
+/* gen_list->gen function for sha256 */
+char *
+_crypt_gensalt_sha256_rn(unsigned long count,
+						 const char *input, int size,
+						 char *output, int output_size)
+{
+	memset(output, 0, output_size);
+	/* set magic byte for sha256crypt */
+	output[0] = '$';
+	output[1] = '5';
+	output[2] = '$';
+
+	return _crypt_gensalt_sha(count, input, size, output, output_size);
+}