26 Oct
2020
26 Oct
'20
11:40 p.m.
On Mon, Oct 26, 2020 at 06:10:59PM -0500, Gustavo A. R. Silva wrote:
On Mon, Oct 26, 2020 at 04:21:48PM -0500, Gustavo A. R. Silva wrote:
+/*
- Linux v4.12 and later removed the 64-byte limit on salg_name[]; it's now an
- arbitrary-length field. We had to keep the original struct above for source
- compatibility with existing userspace programs, though. Use the new struct
- below if support for very long algorithm names is needed. To do this,
- allocate 'sizeof(struct sockaddr_alg_new) + strlen(algname) + 1' bytes, and
- copy algname (including the null terminator) into salg_name.
- */
+struct sockaddr_alg_new {
- __u16 salg_family;
- __u8 salg_type[14];
- __u32 salg_feat;
- __u32 salg_mask;
- __u8 salg_name[];
+};
How something like this, instead:
struct sockaddr_alg {
- __u16 salg_family;
- __u8 salg_type[14];
- __u32 salg_feat;
- __u32 salg_mask;
- __u8 salg_name[64];
- union {
struct {__u16 salg_v1_family;__u8 salg_v1_type[14];__u32 salg_v1_feat;__u32 salg_v1_mask;__u8 salg_name[64];};struct {__u16 salg_family;__u8 salg_type[14];__u32 salg_feat;__u32 salg_mask;__u8 salg_name_new[];};- };
};
Something similar to the following approach might work:
https://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux.git/commit/...
I suppose so. It's very confusing to see a union like that at first glance, though. It definitely needs an explanatory comment...
- Eric