crypto: rng - RNGs must return 0 in success case
Change the RNGs to always return 0 in success case.
This patch ensures that seqiv.c works with RNGs other than krng. seqiv
expects that any return code other than 0 is an error. Without the
patch, rfc4106(gcm(aes)) will not work when using a DRBG or an ANSI
X9.31 RNG.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/crypto/ansi_cprng.c b/crypto/ansi_cprng.c
index 6f5bebc..765fe76 100644
--- a/crypto/ansi_cprng.c
+++ b/crypto/ansi_cprng.c
@@ -210,7 +210,11 @@
byte_count = DEFAULT_BLK_SZ;
}
- err = byte_count;
+ /*
+ * Return 0 in case of success as mandated by the kernel
+ * crypto API interface definition.
+ */
+ err = 0;
dbgprint(KERN_CRIT "getting %d random bytes for context %p\n",
byte_count, ctx);
diff --git a/crypto/drbg.c b/crypto/drbg.c
index 56c1d7e..b69409c 100644
--- a/crypto/drbg.c
+++ b/crypto/drbg.c
@@ -1280,7 +1280,7 @@
* as defined in SP800-90A. The additional input is mixed into
* the state in addition to the pulled entropy.
*
- * return: generated number of bytes
+ * return: 0 when all bytes are generated; < 0 in case of an error
*/
static int drbg_generate(struct drbg_state *drbg,
unsigned char *buf, unsigned int buflen,
@@ -1419,6 +1419,11 @@
}
#endif
+ /*
+ * All operations were successful, return 0 as mandated by
+ * the kernel crypto API interface.
+ */
+ len = 0;
err:
shadow->d_ops->crypto_fini(shadow);
drbg_restore_shadow(drbg, &shadow);
diff --git a/include/crypto/rng.h b/include/crypto/rng.h
index a16fb10..6e28ea5 100644
--- a/include/crypto/rng.h
+++ b/include/crypto/rng.h
@@ -103,8 +103,7 @@
* This function fills the caller-allocated buffer with random numbers using the
* random number generator referenced by the cipher handle.
*
- * Return: > 0 function was successful and returns the number of generated
- * bytes; < 0 if an error occurred
+ * Return: 0 function was successful; < 0 if an error occurred
*/
static inline int crypto_rng_get_bytes(struct crypto_rng *tfm,
u8 *rdata, unsigned int dlen)