This abstract class provides a common interface to message digest implementation classes written in C.
Digest::Base provides a common interface to message digest classes written in C. These classes must provide a struct of type rb_digest_metadata_t:
typedef int (*rb_digest_hash_init_func_t)(void *); typedef void (*rb_digest_hash_update_func_t)(void *, unsigned char *, size_t); typedef int (*rb_digest_hash_finish_func_t)(void *, unsigned char *); typedef struct { int api_version; size_t digest_len; size_t block_len; size_t ctx_size; rb_digest_hash_init_func_t init_func; rb_digest_hash_update_func_t update_func; rb_digest_hash_finish_func_t finish_func; } rb_digest_metadata_t;
This structure must be set as an instance variable named
metadata
(without the +@+ in front of the name). By example:
static const rb_digest_metadata_t sha1 = { RUBY_DIGEST_API_VERSION, SHA1_DIGEST_LENGTH, SHA1_BLOCK_LENGTH, sizeof(SHA1_CTX), (rb_digest_hash_init_func_t)SHA1_Init, (rb_digest_hash_update_func_t)SHA1_Update, (rb_digest_hash_finish_func_t)SHA1_Finish, }; rb_ivar_set(cDigest_SHA1, rb_intern("metadata"), Data_Wrap_Struct(0, 0, 0, (void *)&sha1));
Update the digest using given string and return self
.
static VALUE rb_digest_base_update(VALUE self, VALUE str) { rb_digest_metadata_t *algo; void *pctx; algo = get_digest_obj_metadata(self); TypedData_Get_Struct(self, void, &digest_type, pctx); StringValue(str); algo->update_func(pctx, (unsigned char *)RSTRING_PTR(str), RSTRING_LEN(str)); RB_GC_GUARD(str); return self; }
Return the block length of the digest in bytes.
static VALUE rb_digest_base_block_length(VALUE self) { rb_digest_metadata_t *algo; algo = get_digest_obj_metadata(self); return INT2NUM(algo->block_len); }
Return the length of the hash value in bytes.
static VALUE rb_digest_base_digest_length(VALUE self) { rb_digest_metadata_t *algo; algo = get_digest_obj_metadata(self); return INT2NUM(algo->digest_len); }
Reset the digest to its initial state and return self
.
static VALUE rb_digest_base_reset(VALUE self) { rb_digest_metadata_t *algo; void *pctx; algo = get_digest_obj_metadata(self); TypedData_Get_Struct(self, void, &digest_type, pctx); algo_init(algo, pctx); return self; }
Update the digest using given string and return self
.
static VALUE rb_digest_base_update(VALUE self, VALUE str) { rb_digest_metadata_t *algo; void *pctx; algo = get_digest_obj_metadata(self); TypedData_Get_Struct(self, void, &digest_type, pctx); StringValue(str); algo->update_func(pctx, (unsigned char *)RSTRING_PTR(str), RSTRING_LEN(str)); RB_GC_GUARD(str); return self; }