rpcgss: krb5: clean up some goto's, etc.

Remove some unnecessary goto labels; clean up some return values; etc.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

net/sunrpc/auth_gss/gss_krb5_seal.c

@@ -90,7 +90,7 @@ gss_get_mic_kerberos(struct gss_ctx *gss_ctx, struct xdr_buf *text,
 	if (ctx->sealalg != SEAL_ALG_NONE && ctx->sealalg != SEAL_ALG_DES) {
 		dprintk("RPC:      gss_krb5_seal: ctx->sealalg %d not supported\n",
 			ctx->sealalg);
-		goto out_err;
+		return GSS_S_FAILURE;
 	}
 
 	token->len = g_token_size(&ctx->mech_used, 22);
@@ -109,11 +109,11 @@ gss_get_mic_kerberos(struct gss_ctx *gss_ctx, struct xdr_buf *text,
 	memset(krb5_hdr + 4, 0xff, 4);
 
 	if (make_checksum("md5", krb5_hdr, 8, text, 0, &md5cksum))
-		goto out_err;
+		return GSS_S_FAILURE;
 
 	if (krb5_encrypt(ctx->seq, NULL, md5cksum.data,
 			  md5cksum.data, md5cksum.len))
-		goto out_err;
+		return GSS_S_FAILURE;
 	memcpy(krb5_hdr + 16,
 	       md5cksum.data + md5cksum.len - KRB5_CKSUM_LENGTH,
 	       KRB5_CKSUM_LENGTH);
@@ -124,9 +124,7 @@ gss_get_mic_kerberos(struct gss_ctx *gss_ctx, struct xdr_buf *text,
 
 	if ((krb5_make_seq_num(ctx->seq, ctx->initiate ? 0 : 0xff,
 			       seq_send, krb5_hdr + 16, krb5_hdr + 8)))
-		goto out_err;
+		return GSS_S_FAILURE;
 
 	return ((ctx->endtime < now) ? GSS_S_CONTEXT_EXPIRED : GSS_S_COMPLETE);
-out_err:
-	return GSS_S_FAILURE;
 }

net/sunrpc/auth_gss/gss_krb5_unseal.c

@@ -85,69 +85,56 @@ gss_verify_mic_kerberos(struct gss_ctx *gss_ctx,
 	s32			seqnum;
 	unsigned char		*ptr = (unsigned char *)read_token->data;
 	int			bodysize;
-	u32			ret = GSS_S_DEFECTIVE_TOKEN;
 
 	dprintk("RPC:      krb5_read_token\n");
 
 	if (g_verify_token_header(&ctx->mech_used, &bodysize, &ptr,
 					read_token->len))
-		goto out;
+		return GSS_S_DEFECTIVE_TOKEN;
 
 	if ((*ptr++ != ((KG_TOK_MIC_MSG>>8)&0xff)) ||
 	    (*ptr++ != ( KG_TOK_MIC_MSG    &0xff))   )
-		goto out;
+		return GSS_S_DEFECTIVE_TOKEN;
 
 	/* XXX sanity-check bodysize?? */
 
-	/* get the sign and seal algorithms */
-
 	signalg = ptr[0] + (ptr[1] << 8);
 	sealalg = ptr[2] + (ptr[3] << 8);
 
 	/* Sanity checks */
 
 	if ((ptr[4] != 0xff) || (ptr[5] != 0xff))
-		goto out;
+		return GSS_S_DEFECTIVE_TOKEN;
 
 	if (sealalg != 0xffff)
-		goto out;
+		return GSS_S_DEFECTIVE_TOKEN;
 	if (signalg != SGN_ALG_DES_MAC_MD5)
-		goto out;
+		return GSS_S_DEFECTIVE_TOKEN;
 
-	ret = make_checksum("md5", ptr - 2, 8, message_buffer, 0, &md5cksum);
-	if (ret)
-		goto out;
+	if (make_checksum("md5", ptr - 2, 8, message_buffer, 0, &md5cksum))
+		return GSS_S_FAILURE;
 
-	ret = krb5_encrypt(ctx->seq, NULL, md5cksum.data,
-			   md5cksum.data, 16);
-	if (ret)
-		goto out;
+	if (krb5_encrypt(ctx->seq, NULL, md5cksum.data, md5cksum.data, 16))
+		return GSS_S_FAILURE;
 
-	if (memcmp(md5cksum.data + 8, ptr + 14, 8)) {
-		ret = GSS_S_BAD_SIG;
-		goto out;
-	}
+	if (memcmp(md5cksum.data + 8, ptr + 14, 8))
+		return GSS_S_BAD_SIG;
 
 	/* it got through unscathed.  Make sure the context is unexpired */
 
 	now = get_seconds();
 
-	ret = GSS_S_CONTEXT_EXPIRED;
 	if (now > ctx->endtime)
-		goto out;
+		return GSS_S_CONTEXT_EXPIRED;
 
 	/* do sequencing checks */
 
-	ret = GSS_S_BAD_SIG;
-	if ((ret = krb5_get_seq_num(ctx->seq, ptr + 14, ptr + 6, &direction,
-				    &seqnum)))
-		goto out;
+	if (krb5_get_seq_num(ctx->seq, ptr + 14, ptr + 6, &direction, &seqnum))
+		return GSS_S_FAILURE;
 
 	if ((ctx->initiate && direction != 0xff) ||
 	    (!ctx->initiate && direction != 0))
-		goto out;
+		return GSS_S_BAD_SIG;
 
-	ret = GSS_S_COMPLETE;
-out:
-	return ret;
+	return GSS_S_COMPLETE;
 }

net/sunrpc/auth_gss/gss_krb5_wrap.c

@@ -136,7 +136,7 @@ gss_wrap_kerberos(struct gss_ctx *ctx, int offset,
 	if (kctx->sealalg != SEAL_ALG_NONE && kctx->sealalg != SEAL_ALG_DES) {
 		dprintk("RPC:      gss_krb5_seal: kctx->sealalg %d not supported\n",
 			kctx->sealalg);
-		goto out_err;
+		return GSS_S_FAILURE;
 	}
 
 	blocksize = crypto_blkcipher_blocksize(kctx->enc);
@@ -178,12 +178,12 @@ gss_wrap_kerberos(struct gss_ctx *ctx, int offset,
 	buf->pages = pages;
 	if (make_checksum("md5", krb5_hdr, 8, buf,
 				offset + headlen - blocksize, &md5cksum))
-		goto out_err;
+		return GSS_S_FAILURE;
 	buf->pages = tmp_pages;
 
 	if (krb5_encrypt(kctx->seq, NULL, md5cksum.data,
 			  md5cksum.data, md5cksum.len))
-		goto out_err;
+		return GSS_S_FAILURE;
 	memcpy(krb5_hdr + 16,
 	       md5cksum.data + md5cksum.len - KRB5_CKSUM_LENGTH,
 	       KRB5_CKSUM_LENGTH);
@@ -196,15 +196,13 @@ gss_wrap_kerberos(struct gss_ctx *ctx, int offset,
 	 * and encrypt at the same time: */
 	if ((krb5_make_seq_num(kctx->seq, kctx->initiate ? 0 : 0xff,
 			       seq_send, krb5_hdr + 16, krb5_hdr + 8)))
-		goto out_err;
+		return GSS_S_FAILURE;
 
 	if (gss_encrypt_xdr_buf(kctx->enc, buf, offset + headlen - blocksize,
 									pages))
-		goto out_err;
+		return GSS_S_FAILURE;
 
 	return ((kctx->endtime < now) ? GSS_S_CONTEXT_EXPIRED : GSS_S_COMPLETE);
-out_err:
-	return GSS_S_FAILURE;
 }
 
 u32
@@ -220,7 +218,6 @@ gss_unwrap_kerberos(struct gss_ctx *ctx, int offset, struct xdr_buf *buf)
 	s32			seqnum;
 	unsigned char		*ptr;
 	int			bodysize;
-	u32			ret = GSS_S_DEFECTIVE_TOKEN;
 	void			*data_start, *orig_start;
 	int			data_len;
 	int			blocksize;
@@ -230,11 +227,11 @@ gss_unwrap_kerberos(struct gss_ctx *ctx, int offset, struct xdr_buf *buf)
 	ptr = (u8 *)buf->head[0].iov_base + offset;
 	if (g_verify_token_header(&kctx->mech_used, &bodysize, &ptr,
 					buf->len - offset))
-		goto out;
+		return GSS_S_DEFECTIVE_TOKEN;
 
 	if ((*ptr++ != ((KG_TOK_WRAP_MSG>>8)&0xff)) ||
 	    (*ptr++ !=  (KG_TOK_WRAP_MSG    &0xff))   )
-		goto out;
+		return GSS_S_DEFECTIVE_TOKEN;
 
 	/* XXX sanity-check bodysize?? */
 
@@ -246,18 +243,18 @@ gss_unwrap_kerberos(struct gss_ctx *ctx, int offset, struct xdr_buf *buf)
 	/* Sanity checks */
 
 	if ((ptr[4] != 0xff) || (ptr[5] != 0xff))
-		goto out;
+		return GSS_S_DEFECTIVE_TOKEN;
 
 	if (sealalg == 0xffff)
-		goto out;
+		return GSS_S_DEFECTIVE_TOKEN;
 	if (signalg != SGN_ALG_DES_MAC_MD5)
-		goto out;
+		return GSS_S_DEFECTIVE_TOKEN;
 
 	/* in the current spec, there is only one valid seal algorithm per
 	   key type, so a simple comparison is ok */
 
 	if (sealalg != kctx->sealalg)
-		goto out;
+		return GSS_S_DEFECTIVE_TOKEN;
 
 	/* there are several mappings of seal algorithms to sign algorithms,
 	   but few enough that we can try them all. */
@@ -266,45 +263,39 @@ gss_unwrap_kerberos(struct gss_ctx *ctx, int offset, struct xdr_buf *buf)
 	    (kctx->sealalg == SEAL_ALG_1 && signalg != SGN_ALG_3) ||
 	    (kctx->sealalg == SEAL_ALG_DES3KD &&
 	     signalg != SGN_ALG_HMAC_SHA1_DES3_KD))
-		goto out;
+		return GSS_S_DEFECTIVE_TOKEN;
 
 	if (gss_decrypt_xdr_buf(kctx->enc, buf,
 			ptr + 22 - (unsigned char *)buf->head[0].iov_base))
-		goto out;
+		return GSS_S_DEFECTIVE_TOKEN;
 
-	ret = make_checksum("md5", ptr - 2, 8, buf,
-		 ptr + 22 - (unsigned char *)buf->head[0].iov_base, &md5cksum);
-	if (ret)
-		goto out;
+	if (make_checksum("md5", ptr - 2, 8, buf,
+		 ptr + 22 - (unsigned char *)buf->head[0].iov_base, &md5cksum))
+		return GSS_S_FAILURE;
 
-	ret = krb5_encrypt(kctx->seq, NULL, md5cksum.data,
-			   md5cksum.data, md5cksum.len);
-	if (ret)
-		goto out;
+	if (krb5_encrypt(kctx->seq, NULL, md5cksum.data,
+			   md5cksum.data, md5cksum.len))
+		return GSS_S_FAILURE;
 
-	if (memcmp(md5cksum.data + 8, ptr + 14, 8)) {
-		ret = GSS_S_BAD_SIG;
-		goto out;
-	}
+	if (memcmp(md5cksum.data + 8, ptr + 14, 8))
+		return GSS_S_BAD_SIG;
 
 	/* it got through unscathed.  Make sure the context is unexpired */
 
 	now = get_seconds();
 
-	ret = GSS_S_CONTEXT_EXPIRED;
 	if (now > kctx->endtime)
-		goto out;
+		return GSS_S_CONTEXT_EXPIRED;
 
 	/* do sequencing checks */
 
-	ret = GSS_S_BAD_SIG;
-	if ((ret = krb5_get_seq_num(kctx->seq, ptr + 14, ptr + 6, &direction,
-				    &seqnum)))
-		goto out;
+	if (krb5_get_seq_num(kctx->seq, ptr + 14, ptr + 6, &direction,
+				    &seqnum))
+		return GSS_S_BAD_SIG;
 
 	if ((kctx->initiate && direction != 0xff) ||
 	    (!kctx->initiate && direction != 0))
-		goto out;
+		return GSS_S_BAD_SIG;
 
 	/* Copy the data back to the right position.  XXX: Would probably be
 	 * better to copy and encrypt at the same time. */
@@ -317,11 +308,8 @@ gss_unwrap_kerberos(struct gss_ctx *ctx, int offset, struct xdr_buf *buf)
 	buf->head[0].iov_len -= (data_start - orig_start);
 	buf->len -= (data_start - orig_start);
 
-	ret = GSS_S_DEFECTIVE_TOKEN;
 	if (gss_krb5_remove_padding(buf, blocksize))
-		goto out;
+		return GSS_S_DEFECTIVE_TOKEN;
 
-	ret = GSS_S_COMPLETE;
-out:
-	return ret;
+	return GSS_S_COMPLETE;
 }