Hi,
I am a newbie to openssl and have run into what is probably a stupid
question. I am using openssl-1.0.0c.
So here it goes.
I wanted to look at how openssl implemented the following functions which
are defined in the openssl crypto library in openssl/crytpo/sha.h:
int SHA1_Init(SHA_CTX *c);
int SHA1_Update(SHA_CTX *c, const void *data, size_t len);
int SHA1_Final(unsigned char *md, SHA_CTX *c);
unsigned char *SHA1(const unsigned char *d, size_t n, unsigned char *md);
In file sha1.c I only see the function implementation for SHA1 which is a
wrapper function that invokes SHA1_init, SHA1_Update, and SHA1_Final. I was
expecting to see the implementations for all four of these functions in file
sha1_one.c. But I only see the implementation for the wrapper function SHA1
in that file.
Where are these functions suppose to be implemented?
[u...@centos sha]$ pwd
/home/user/OPENSSLTEST/openssl-1.0.0c/crypto/sha
[u...@centos sha]$ grep SHA1_Final *
sha1.c: SHA1_Final(&(md[0]),&c);
sha1_one.c: SHA1_Final(md,&c);
sha.h:int SHA1_Final(unsigned char *md, SHA_CTX *c);
sha_locl.h:# define HASH_FINAL SHA1_Final
For instance above I see calls to SHA1_Final; but I don't see the actual
implementation of that function.
By comparison for the SHA512 case I do see all of the following functions in
sha512.c in this same directory:
SHA512_Init. SHA512_Update, SHA512_Final, and of course the wrapper
function SHA512 implementations can all be found in sha512.c.
For example:
[u...@centos sha]$ grep SHA512_Final *
*sha512.c:int SHA512_Final (unsigned char *md, SHA512_CTX *c)*
sha512.c:{ return SHA512_Final (md,c); }
sha512.c: SHA512_Final(md,&c);
sha512.c: SHA512_Final(md,&c);
sha.h:int SHA512_Final(unsigned char *md, SHA512_CTX *c);
I don't understand how this works obviously. Any information would be
appreciated. I want to use this in an embedded application.
I also noticed macros in sha_locl.h for SHA. Is this where the SHA1
functions are implemented?
Thanks,
Stan Joyner
