gc: support HMAC-SHA256 and HMAC-SHA512.

* lib/gc.h: Add gc_hmac_sha256 and gc_hmac_sha512.
* lib/gc-libgcrypt.c (gc_hmac_sha256, gc_hmac_sha512): New
functions.
(gc_hmac_md5): Use symbolic constant.
* lib/gc-gnulib.c: Include hmac.h for HMAC-SHA256/512 too.
(gc_hmac_sha256, gc_hmac_sha512): New functions.
* lib/hmac.h: Add hmac_sha256 and hmac_sha512 prototypes.
* m4/sha256.m4: Protect against empty expansion.
* m4/sha512.m4: Likewise.
* lib/hmac-sha256.c: New file.
* lib/hmac-sha512.c: Likewise.
* m4/gc-hmac-sha256.m4: Likewise.
* m4/gc-hmac-sha512.m4: Likewise.
* m4/gc-sha256.m4: Likewise.
* m4/gc-sha512.m4: Likewise.
* modules/crypto/gc-hmac-sha256: Likewise.
* modules/crypto/gc-hmac-sha256-tests: Likewise.
* modules/crypto/gc-hmac-sha512: Likewise.
* modules/crypto/gc-hmac-sha512-tests: Likewise.
* modules/crypto/hmac-sha256: Likewise.
* modules/crypto/hmac-sha256-tests: Likewise.
* modules/crypto/hmac-sha512: Likewise.
* modules/crypto/hmac-sha512-tests: Likewise.
* tests/test-gc-hmac-sha256.c: Likewise.
* tests/test-gc-hmac-sha512.c: Likewise
* tests/test-hmac-sha256.c: Likewise.
* tests/test-hmac-sha512.c: Likewise

1 files changed, 4 insertions, 0 deletions

diff --git a/lib/gc.h b/lib/gc.h
index 1482ba5ceb..d2cd7d8ac1 100644
--- a/lib/gc.h
+++ b/lib/gc.h
@@ -159,6 +159,10 @@ extern Gc_rc gc_hmac_md5 (const void *key, size_t keylen,
                           const void *in, size_t inlen, char *resbuf);
 extern Gc_rc gc_hmac_sha1 (const void *key, size_t keylen,
                            const void *in, size_t inlen, char *resbuf);
+extern Gc_rc gc_hmac_sha256 (const void *key, size_t keylen,
+                             const void *in, size_t inlen, char *resbuf);
+extern Gc_rc gc_hmac_sha512 (const void *key, size_t keylen,
+                             const void *in, size_t inlen, char *resbuf);
 
 /* Derive cryptographic keys from a password P of length PLEN, with
    salt S of length SLEN, placing the result in pre-allocated buffer