Support SHA-3 hash functions

[yuan-xy]

add SHA3_224, SHA3_256, SHA3_384 and SHA3_512 class under OpenSSL::Digest module.

[ioquatix]

I wonder if we can use something better than class name. e.g. constant.

[ioquatix]

Maybe have SHA3_224::NAME = "SHA3-224". What do you think?

[yuan-xy]

Maybe have SHA3_224::NAME = "SHA3-224". What do you think?

Maybe it works, but I can't figure out how to implements this. In addtion, there is a 'name' method there:
rb_define_method(cDigest, "name", ossl_digest_name, 0);

[ioquatix]

Can this help you?

https://silverhammermba.github.io/emberb/c/#constants-1

[yuan-xy]

how about this,

if(strncmp(name, "SHA3_", 5) && strlen(name)==9) {
char n_name[9];
strncpy(n_name, name, 9);
n_name[4] = '-';
md = EVP_get_digestbyname(n_name);

which is better than original code

char *pos = strchr(name, '_');

if(pos) {
	char n_name[9];
	char *n_pos;
	strncpy(n_name, name, 9);
	n_pos = strchr(n_name, '_');
	*n_pos = '-';
	md = EVP_get_digestbyname(n_name);

[yuan-xy]

how about this code:

if(strcmp(name, "SHA3_224") {
md = EVP_get_digestbyname("SHA3-224");
else if(strcmp(name, "SHA3_256") {
md = EVP_get_digestbyname("SHA3-256");
else if(strcmp(name, "SHA3_384") {
md = EVP_get_digestbyname("SHA3-384");
else if(strcmp(name, "SHA3_512") {
md = EVP_get_digestbyname("SHA3-512");
}

[ioquatix]

I still think using constant is better, @mame what do you think?

[yuan-xy]

Maybe someone else can help support SHA-3 hash functions in ruby.

[ioquatix]

So, for each class, you need to write something like:

rb_define_const(digest_class, "NAME", "SHA3-384");

Then, in the method to create it, you need to use:

rb_const_get_at(digest_class, rb_intern("NAME"));

Does that make sense?

[ioquatix]

@yuan-xy you are very close to having a workable solution. Let me know if you'd like to finish this off.

[yuan-xy]

I’m on a long vacation, I will figure out how to finish it after vacation. 在 2019年9月28日，05:29，Samuel Williams <notifications@github.com<mailto:notifications@github.com>> 写道： @yuan-xy<https://github.com/yuan-xy> you are very close to having a workable solution. Let me know if you'd like to finish this off. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub<#271?email_source=notifications&email_token=AAC55MX7OLQ3FX4ZZSG5TJ3QLZ3NHA5CNFSM4ISSOHB2YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD72EOII#issuecomment-536102689>, or mute the thread<https://github.com/notifications/unsubscribe-auth/AAC55MQ62247AGHOSJJLQBLQLZ3NHANCNFSM4ISSOHBQ>.

[yuan-xy]

After many attempts, I still don't know how to implement it use rb_define_const.
The digest class has not initialized when ossl_evp_get_digestbyname being called. How to define this:

 rb_define_const(digest_class, "NAME", "SHA3-384");