/** Length of hex encoding of SHA512 digest, not including final NUL. */
#define HEX_DIGEST512_LEN 128
+/**
+ * An identifier for a cryptographic digest algorithm.
+ **/
typedef enum {
DIGEST_SHA1 = 0,
DIGEST_SHA256 = 1,
DIGEST_SHA3_256 = 3,
DIGEST_SHA3_512 = 4,
} digest_algorithm_t;
+/** Number of digest algorithms that we know */
#define N_DIGEST_ALGORITHMS (DIGEST_SHA3_512+1)
+/** Number of digest algorithms to compute when computing "all the
+ * commonly used digests."
+ *
+ * (This is used in common_digests_t and related functions.)
+ */
#define N_COMMON_DIGEST_ALGORITHMS (DIGEST_SHA256+1)
+/**
+ * Bytes of storage needed to record the state of an in-progress SHA-1 digest.
+ *
+ * This is a deliberate overestimate.
+ **/
#define DIGEST_CHECKPOINT_BYTES (SIZEOF_VOID_P + 512)
+
/** Structure used to temporarily save the a digest object. Only implemented
* for SHA1 digest for now. */
typedef struct crypto_digest_checkpoint_t {
#ifdef ENABLE_NSS
+ /** The number of bytes used in <b>mem</b>. */
unsigned int bytes_used;
#endif
+ /** A buffer to store the SHA1 state. Its contents are unspecified, and
+ * are managed by the underlying crypto library.*/
uint8_t mem[DIGEST_CHECKPOINT_BYTES];
} crypto_digest_checkpoint_t;
* once.
**/
typedef struct {
+ /** An array of digest outputs, one for each "common" digest algorithm. */
char d[N_COMMON_DIGEST_ALGORITHMS][DIGEST256_LEN];
} common_digests_t;
+/**
+ * State for computing a digest over a stream of data.
+ **/
typedef struct crypto_digest_t crypto_digest_t;
+
+/**
+ * State for computing an "extendable-output function" (like SHAKE) over a
+ * stream of data, and/or streaming the output.
+ **/
typedef struct crypto_xof_t crypto_xof_t;
struct smartlist_t;
crypto_digest_t *crypto_digest256_new(digest_algorithm_t algorithm);
crypto_digest_t *crypto_digest512_new(digest_algorithm_t algorithm);
void crypto_digest_free_(crypto_digest_t *digest);
+/**
+ * Release all storage held in <b>d</b>, and set it to NULL.
+ **/
#define crypto_digest_free(d) \
FREE_AND_NULL(crypto_digest_t, crypto_digest_free_, (d))
void crypto_digest_add_bytes(crypto_digest_t *digest, const char *data,
void crypto_xof_add_bytes(crypto_xof_t *xof, const uint8_t *data, size_t len);
void crypto_xof_squeeze_bytes(crypto_xof_t *xof, uint8_t *out, size_t len);
void crypto_xof_free_(crypto_xof_t *xof);
+/**
+ * Release all storage held in <b>xof</b>, and set it to NULL.
+ **/
#define crypto_xof_free(xof) \
FREE_AND_NULL(crypto_xof_t, crypto_xof_free_, (xof))
void crypto_xof(uint8_t *output, size_t output_len,
static size_t
crypto_digest_alloc_bytes(digest_algorithm_t alg)
{
- /* Helper: returns the number of bytes in the 'f' field of 'st' */
+ /** Helper: returns the number of bytes in the 'f' field of 'st' */
#define STRUCT_FIELD_SIZE(st, f) (sizeof( ((st*)0)->f ))
- /* Gives the length of crypto_digest_t through the end of the field 'd' */
+ /** Gives the length of crypto_digest_t through the end of the field 'd' */
#define END_OF_FIELD(f) (offsetof(crypto_digest_t, f) + \
STRUCT_FIELD_SIZE(crypto_digest_t, f))
switch (alg) {
(unsigned char*)hmac_out, NULL);
tor_assert(rv);
}
-