| Message ID | 20120601155456.5114.68007.stgit@sifl |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Paul Moore <pmoore@redhat.com> Date: Fri, 01 Jun 2012 11:54:56 -0400 > When NetLabel is not enabled, e.g. CONFIG_NETLABEL=n, and the system > receives a CIPSO tagged packet it is dropped (cipso_v4_validate() > returns non-zero). In most cases this is the correct and desired > behavior, however, in the case where we are simply forwarding the > traffic, e.g. acting as a network bridge, this becomes a problem. > > This patch fixes the forwarding problem by providing the basic CIPSO > validation code directly in ip_options_compile() without the need for > the NetLabel or CIPSO code. The new validation code can not perform > any of the CIPSO option label/value verification that > cipso_v4_validate() does, but it can verify the basic CIPSO option > format. > > The behavior when NetLabel is enabled is unchanged. > > CC: stable@vger.kernel.org > Signed-off-by: Paul Moore <pmoore@redhat.com> > I like this a lot better, applied, thanks Paul. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/include/net/cipso_ipv4.h b/include/net/cipso_ipv4.h index 9808877..a7a683e 100644 --- a/include/net/cipso_ipv4.h +++ b/include/net/cipso_ipv4.h @@ -42,6 +42,7 @@ #include <net/netlabel.h> #include <net/request_sock.h> #include <linux/atomic.h> +#include <asm/unaligned.h> /* known doi values */ #define CIPSO_V4_DOI_UNKNOWN 0x00000000 @@ -285,7 +286,33 @@ static inline int cipso_v4_skbuff_getattr(const struct sk_buff *skb, static inline int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option) { - return -ENOSYS; + unsigned char *opt = *option; + unsigned char err_offset = 0; + u8 opt_len = opt[1]; + u8 opt_iter; + + if (opt_len < 8) { + err_offset = 1; + goto out; + } + + if (get_unaligned_be32(&opt[2]) == 0) { + err_offset = 2; + goto out; + } + + for (opt_iter = 6; opt_iter < opt_len;) { + if (opt[opt_iter + 1] > (opt_len - opt_iter)) { + err_offset = opt_iter + 1; + goto out; + } + opt_iter += opt[opt_iter + 1]; + } + +out: + *option = opt + err_offset; + return err_offset; + } #endif /* CONFIG_NETLABEL */
When NetLabel is not enabled, e.g. CONFIG_NETLABEL=n, and the system receives a CIPSO tagged packet it is dropped (cipso_v4_validate() returns non-zero). In most cases this is the correct and desired behavior, however, in the case where we are simply forwarding the traffic, e.g. acting as a network bridge, this becomes a problem. This patch fixes the forwarding problem by providing the basic CIPSO validation code directly in ip_options_compile() without the need for the NetLabel or CIPSO code. The new validation code can not perform any of the CIPSO option label/value verification that cipso_v4_validate() does, but it can verify the basic CIPSO option format. The behavior when NetLabel is enabled is unchanged. CC: stable@vger.kernel.org Signed-off-by: Paul Moore <pmoore@redhat.com> -- ChangeLog -v2 * Moved the CONFIG_NETLABEL=n code into cipso_ipv4.h -v1 * Initial version --- include/net/cipso_ipv4.h | 29 ++++++++++++++++++++++++++++- 1 files changed, 28 insertions(+), 1 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html