1 #ifndef BLAKE3_H
2 #define BLAKE3_H
3 
4 #include <stddef.h>
5 #include <stdint.h>
6 
7 #ifdef __cplusplus
8 extern "C" {
9 #endif
10 
11 #define BLAKE3_KEY_LEN 32
12 #define BLAKE3_OUT_LEN 32
13 #define BLAKE3_BLOCK_LEN 64
14 #define BLAKE3_CHUNK_LEN 1024
15 #define BLAKE3_MAX_DEPTH 54
16 #define BLAKE3_MAX_SIMD_DEGREE 16
17 
18 // This struct is a private implementation detail. It has to be here because
19 // it's part of blake3_hasher below.
20 typedef struct {
21   uint32_t cv[8];
22   uint64_t chunk_counter;
23   uint8_t buf[BLAKE3_BLOCK_LEN];
24   uint8_t buf_len;
25   uint8_t blocks_compressed;
26   uint8_t flags;
27 } blake3_chunk_state;
28 
29 typedef struct {
30 	FILE* log;
31 	size_t counter;
32   uint32_t key[8];
33   blake3_chunk_state chunk;
34   uint8_t cv_stack_len;
35   // The stack size is MAX_DEPTH + 1 because we do lazy merging. For example,
36   // with 7 chunks, we have 3 entries in the stack. Adding an 8th chunk
37   // requires a 4th entry, rather than merging everything down to 1, because we
38   // don't know whether more input is coming. This is different from how the
39   // reference implementation does things.
40   uint8_t cv_stack[(BLAKE3_MAX_DEPTH + 1) * BLAKE3_OUT_LEN];
41 } blake3_hasher;
42 
43 void blake3_hasher_init(blake3_hasher *self);
44 void blake3_hasher_init_keyed(blake3_hasher *self,
45                               const uint8_t key[BLAKE3_KEY_LEN]);
46 void blake3_hasher_init_derive_key(blake3_hasher *self, const char *context);
47 void blake3_hasher_update(blake3_hasher *self, const void *input,
48                           size_t input_len);
49 void blake3_hasher_finalize(const blake3_hasher *self, uint8_t *out,
50                             size_t out_len);
51 void blake3_hasher_finalize_seek(const blake3_hasher *self, uint64_t seek,
52                                  uint8_t *out, size_t out_len);
53 
54 #ifdef __cplusplus
55 }
56 #endif
57 
58 #endif /* BLAKE3_H */
59