Initial import.

inc/bearssl_pem.h

@@ -0,0 +1,125 @@
+/*
+ * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining 
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be 
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef BR_BEARSSL_PEM_H__
+#define BR_BEARSSL_PEM_H__
+
+#include <stddef.h>
+#include <stdint.h>
+
+/*
+ * Context for a PEM decoder.
+ */
+typedef struct {
+	/* CPU for the T0 virtual machine. */
+	struct {
+		uint32_t *dp;
+		uint32_t *rp;
+		const unsigned char *ip;
+	} cpu;
+	uint32_t dp_stack[32];
+	uint32_t rp_stack[32];
+	int err;
+
+	const unsigned char *hbuf;
+	size_t hlen;
+
+	void (*dest)(void *dest_ctx, const void *src, size_t len);
+	void *dest_ctx;
+
+	unsigned char event;
+	char name[128];
+	unsigned char buf[255];
+	size_t ptr;
+
+} br_pem_decoder_context;
+
+/*
+ * Initialise a PEM decoder structure.
+ */
+void br_pem_decoder_init(br_pem_decoder_context *ctx);
+
+/*
+ * Push some bytes into the decoder. Returned value is the number of
+ * bytes actually consumed; this may be less than the number of provided
+ * bytes if an event is produced. When an event is produced, it must
+ * be read (with br_pem_decoder_event()); until the event is read, this
+ * function will return 0.
+ */
+size_t br_pem_decoder_push(br_pem_decoder_context *ctx,
+	const void *data, size_t len);
+
+/*
+ * Set the receiver for decoded data. The provided function (with opaque
+ * context pointer) will be called with successive data chunks.
+ */
+static inline void
+br_pem_decoder_setdest(br_pem_decoder_context *ctx,
+	void (*dest)(void *dest_ctx, const void *src, size_t len),
+	void *dest_ctx)
+{
+	ctx->dest = dest;
+	ctx->dest_ctx = dest_ctx;
+}
+
+/*
+ * Get the last event. This is 0 if no event has been produced. Calling
+ * ths function clears the event and allows new source bytes to be
+ * processed.
+ */
+int br_pem_decoder_event(br_pem_decoder_context *ctx);
+
+/*
+ * This event is called when the start of a new object has been detected.
+ * The object name (normalised to uppercase) can be accessed with
+ * br_pem_decoder_name(). The caller MUST provide an appropriate receiver
+ * (with br_pem_decoder_setdest()) before sending new data bytes.
+ */
+#define BR_PEM_BEGIN_OBJ   1
+
+/*
+ * This event is called when the end of the current object is reached
+ * (normally).
+ */
+#define BR_PEM_END_OBJ     2
+
+/*
+ * This event is called when decoding fails while decoding an object.
+ * This formally closes the current object and brings the decoder back
+ * to the "out of any object" state. The offending line in the source
+ * is consumed.
+ */
+#define BR_PEM_ERROR       3
+
+/*
+ * Get the name of the encountered object. That name is normalised to
+ * uppercase (for ASCII characters).
+ */
+static inline const char *
+br_pem_decoder_name(br_pem_decoder_context *ctx)
+{
+	return ctx->name;
+}
+
+#endif