[PATCH] knfsd: svcrpc: gss: server-side implementation of rpcsec_gss privacy (7c9fdcfb) · Commits · 戴 / test

net/sunrpc/auth_gss/svcauth_gss.c

+147 −7

Original line number	Diff line number	Diff line
		@@ -832,6 +832,74 @@ out:
		return stat;
		}

		static inline int
		total_buf_len(struct xdr_buf *buf)
		{
		return buf->head[0].iov_len + buf->page_len + buf->tail[0].iov_len;
		}

		static void
		fix_priv_head(struct xdr_buf *buf, int pad)
		{
		if (buf->page_len == 0) {
		/* We need to adjust head and buf->len in tandem in this
		* case to make svc_defer() work--it finds the original
		* buffer start using buf->len - buf->head[0].iov_len. */
		buf->head[0].iov_len -= pad;
		}
		}

		static int
		unwrap_priv_data(struct svc_rqst rqstp, struct xdr_buf buf, u32 seq, struct gss_ctx *ctx)
		{
		u32 priv_len, maj_stat;
		int pad, saved_len, remaining_len, offset;

		rqstp->rq_sendfile_ok = 0;

		priv_len = ntohl(svc_getu32(&buf->head[0]));
		if (rqstp->rq_deferred) {
		/* Already decrypted last time through! The sequence number
		* check at out_seq is unnecessary but harmless: */
		goto out_seq;
		}
		/* buf->len is the number of bytes from the original start of the
		* request to the end, where head[0].iov_len is just the bytes
		* not yet read from the head, so these two values are different: */
		remaining_len = total_buf_len(buf);
		if (priv_len > remaining_len)
		return -EINVAL;
		pad = remaining_len - priv_len;
		buf->len -= pad;
		fix_priv_head(buf, pad);

		/* Maybe it would be better to give gss_unwrap a length parameter: */
		saved_len = buf->len;
		buf->len = priv_len;
		maj_stat = gss_unwrap(ctx, 0, buf);
		pad = priv_len - buf->len;
		buf->len = saved_len;
		buf->len -= pad;
		/* The upper layers assume the buffer is aligned on 4-byte boundaries.
		* In the krb5p case, at least, the data ends up offset, so we need to
		* move it around. */
		/* XXX: This is very inefficient. It would be better to either do
		* this while we encrypt, or maybe in the receive code, if we can peak
		* ahead and work out the service and mechanism there. */
		offset = buf->head[0].iov_len % 4;
		if (offset) {
		buf->buflen = RPCSVC_MAXPAYLOAD;
		xdr_shift_buf(buf, offset);
		fix_priv_head(buf, pad);
		}
		if (maj_stat != GSS_S_COMPLETE)
		return -EINVAL;
		out_seq:
		if (ntohl(svc_getu32(&buf->head[0])) != seq)
		return -EINVAL;
		return 0;
		}

		struct gss_svc_data {
		/* decoded gss client cred: */
		struct rpc_gss_wire_cred clcred;
		@@ -1047,7 +1115,14 @@ svcauth_gss_accept(struct svc_rqst rqstp, u32 authp)
		svc_putu32(resv, 0);
		break;
		case RPC_GSS_SVC_PRIVACY:
		/* currently unsupported */
		if (unwrap_priv_data(rqstp, &rqstp->rq_arg,
		gc->gc_seq, rsci->mechctx))
		goto auth_err;
		/* placeholders for length and seq. number: */
		svcdata->body_start = resv->iov_base + resv->iov_len;
		svc_putu32(resv, 0);
		svc_putu32(resv, 0);
		break;
		default:
		goto auth_err;
		}
		@@ -1089,9 +1164,8 @@ svcauth_gss_wrap_resp_integ(struct svc_rqst *rqstp)
		gsd->body_start = NULL;
		/* move accept_stat to right place: */
		memcpy(p, p + 2, 4);
		/* don't wrap in failure case: */
		/* Note: counting on not getting here if call was not even
		* accepted! */
		/* Don't wrap in failure case: */
		/* Counting on not getting here if call was not even accepted! */
		if (*p != rpc_success) {
		resbuf->head[0].iov_len -= 2 * 4;
		goto out;
		@@ -1138,6 +1212,65 @@ out_err:
		return stat;
		}

		static inline int
		svcauth_gss_wrap_resp_priv(struct svc_rqst *rqstp)
		{
		struct gss_svc_data gsd = (struct gss_svc_data )rqstp->rq_auth_data;
		struct rpc_gss_wire_cred *gc = &gsd->clcred;
		struct xdr_buf *resbuf = &rqstp->rq_res;
		struct page **inpages = NULL;
		u32 *p;
		int offset, *len;
		int pad;

		p = gsd->body_start;
		gsd->body_start = NULL;
		/* move accept_stat to right place: */
		memcpy(p, p + 2, 4);
		/* Don't wrap in failure case: */
		/* Counting on not getting here if call was not even accepted! */
		if (*p != rpc_success) {
		resbuf->head[0].iov_len -= 2 * 4;
		return 0;
		}
		p++;
		len = p++;
		offset = (u8 )p - (u8 )resbuf->head[0].iov_base;
		*p++ = htonl(gc->gc_seq);
		inpages = resbuf->pages;
		/* XXX: Would be better to write some xdr helper functions for
		* nfs{2,3,4}xdr.c that place the data right, instead of copying: */
		if (resbuf->tail[0].iov_base && rqstp->rq_restailpage == 0) {
		BUG_ON(resbuf->tail[0].iov_base >= resbuf->head[0].iov_base
		+ PAGE_SIZE);
		BUG_ON(resbuf->tail[0].iov_base < resbuf->head[0].iov_base);
		if (resbuf->tail[0].iov_len + resbuf->head[0].iov_len
		+ 2 * RPC_MAX_AUTH_SIZE > PAGE_SIZE)
		return -ENOMEM;
		memmove(resbuf->tail[0].iov_base + RPC_MAX_AUTH_SIZE,
		resbuf->tail[0].iov_base,
		resbuf->tail[0].iov_len);
		resbuf->tail[0].iov_base += RPC_MAX_AUTH_SIZE;
		}
		if (resbuf->tail[0].iov_base == NULL) {
		if (resbuf->head[0].iov_len + 2*RPC_MAX_AUTH_SIZE > PAGE_SIZE)
		return -ENOMEM;
		resbuf->tail[0].iov_base = resbuf->head[0].iov_base
		+ resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE;
		resbuf->tail[0].iov_len = 0;
		rqstp->rq_restailpage = 0;
		}
		if (gss_wrap(gsd->rsci->mechctx, offset, resbuf, inpages))
		return -ENOMEM;
		*len = htonl(resbuf->len - offset);
		pad = 3 - ((resbuf->len - offset - 1)&3);
		p = (u32 *)(resbuf->tail[0].iov_base + resbuf->tail[0].iov_len);
		memset(p, 0, pad);
		resbuf->tail[0].iov_len += pad;
		resbuf->len += pad;
		return 0;
		}

		static int
		svcauth_gss_release(struct svc_rqst *rqstp)
		{
		@@ -1152,15 +1285,22 @@ svcauth_gss_release(struct svc_rqst *rqstp)
		if (gsd->body_start == NULL)
		goto out;
		/* normally not set till svc_send, but we need it here: */
		resbuf->len = resbuf->head[0].iov_len
		+ resbuf->page_len + resbuf->tail[0].iov_len;
		/* XXX: what for? Do we mess it up the moment we call svc_putu32
		* or whatever? */
		resbuf->len = total_buf_len(resbuf);
		switch (gc->gc_svc) {
		case RPC_GSS_SVC_NONE:
		break;
		case RPC_GSS_SVC_INTEGRITY:
		svcauth_gss_wrap_resp_integ(rqstp);
		stat = svcauth_gss_wrap_resp_integ(rqstp);
		if (stat)
		goto out_err;
		break;
		case RPC_GSS_SVC_PRIVACY:
		stat = svcauth_gss_wrap_resp_priv(rqstp);
		if (stat)
		goto out_err;
		break;
		default:
		goto out_err;
		}

net/sunrpc/svc.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -280,6 +280,7 @@ svc_process(struct svc_serv serv, struct svc_rqst rqstp)
		rqstp->rq_res.page_base = 0;
		rqstp->rq_res.page_len = 0;
		rqstp->rq_res.buflen = PAGE_SIZE;
		rqstp->rq_res.tail[0].iov_base = NULL;
		rqstp->rq_res.tail[0].iov_len = 0;
		/* Will be turned off only in gss privacy case: */
		rqstp->rq_sendfile_ok = 1;

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