Commit cde001e4 authored by Stephan Mueller's avatar Stephan Mueller Committed by Herbert Xu
Browse files

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: default avatarStephan Mueller <smueller@chronox.de>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 4842234f

crypto/ansi_cprng.c

+5 −1
Original line number Diff line number Diff line
@@ -210,7 +210,11 @@ static int get_prng_bytes(char *buf, size_t nbytes, struct prng_context *ctx, 
		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);

crypto/drbg.c

+6 −1
Original line number Diff line number Diff line
@@ -1280,7 +1280,7 @@ static void drbg_restore_shadow(struct drbg_state *drbg, 
 *	  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 @@ static int drbg_generate(struct drbg_state *drbg, 
	}

#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);

include/crypto/rng.h

+1 −2
Original line number Diff line number Diff line
@@ -103,8 +103,7 @@ static inline void crypto_free_rng(struct crypto_rng *tfm) 
 * 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)

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