1 files changed, 96 insertions, 0 deletions
diff --git a/librecrypt_add_algorithm.c b/librecrypt_add_algorithm.c
new file mode 100644
index 0000000..a2d8aa4
--- /dev/null
+++ b/librecrypt_add_algorithm.c
@@ -0,0 +1,96 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+#ifndef TEST
+
+
+ssize_t
+librecrypt_add_algorithm(char *out_buffer, size_t size, char *augend, const char *restrict augment, void *reserved)
+{
+	size_t prefix1 = librecrypt_settings_prefix(augend);
+	size_t prefix2, min, ret, len, phraselen;
+	char *phrase, pad;
+	int strict_pad;
+	const unsigned char *lut;
+	ssize_t r;
+
+#define COPY_PREFIX()\
+	do {\
+		size -= 1u;\
+		min = prefix1 < size ? prefix1 : size;\
+		if (out_buffer != augend)\
+			memmove(out_buffer, augend, min);\
+		out_buffer = &out_buffer[min];\
+		size -= min;\
+		if (size) {\
+			*out_buffer++ = LIBRECRYPT_ALGORITHM_LINK_DELIMITER;\
+			size -= 1u;\
+		}\
+	} while (0)
+
+	if (!augend[prefix1]) {
+		prefix2 = librecrypt_settings_prefix(augment);
+		ret = prefix1 + 1u + prefix2;
+		if (size) {
+			COPY_PREFIX();
+			min = prefix2 < size ? prefix2 : size;
+			memcpy(out_buffer, augment, min);
+			out_buffer[min] = '\0';
+		}
+		return (ssize_t)ret;
+	}
+
+	if (size <= prefix1 + 2u) {
+		phrase = NULL;
+		phraselen = 0u;
+	} else {
+		lut = librecrypt_get_encoding(augend, strlen(augend), &pad, &strict_pad, 1);
+		if (!lut)
+			return -1;
+
+		len = strlen(&augend[prefix1]);
+		r = librecrypt_decode(NULL, 0, &augend[prefix1], len, lut, pad, strict_pad);
+		if (r <= 0) {
+			if (!r)
+				abort();
+			return -1;
+		}
+		phraselen = (size_t)r;
+		phrase = malloc(phraselen);
+		if (!phrase)
+			return -1;
+		if (librecrypt_decode(phrase, phraselen, &augend[prefix1], len, lut, pad, strict_pad) != r)
+			abort();
+	}
+
+	COPY_PREFIX();
+	ret = prefix1 + 1u;
+	r = librecrypt_crypt(out_buffer, size + 1u, phrase, phraselen, augment, reserved);
+	if (r <= 0) {
+		librecrypt_wipe(phrase, phraselen);
+		free(phrase);
+		if (!r)
+			abort();
+		return -1;
+	}
+	ret += (size_t)r;
+
+	librecrypt_wipe(phrase, phraselen);
+	free(phrase);
+	return (ssize_t)ret;
+}
+
+
+#else
+
+
+int
+main(void)
+{
+	SET_UP_ALARM();
+
+	return 0;
+}
+
+
+#endif
+/* TODO test */