[PULL 21/22] linux-user: Implement SOL_ALG encryption support

[Laurent Vivier <laurent@vivier.eu>]

From: Helge Deller <deller@gmx.de>

Add suport to handle SOL_ALG packets via sendmsg() and recvmsg().
This allows emulated userspace to use encryption functionality.

Tested with the debian ell package with hppa guest on x86_64 host.

Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20221212173416.90590-1-deller@gmx.de>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
---
 linux-user/syscall.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 55d53b344b84..a0d2beddaa4e 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -1829,6 +1829,14 @@ static inline abi_long target_to_host_cmsg(struct msghdr *msgh,
             __get_user(cred->pid, &target_cred->pid);
             __get_user(cred->uid, &target_cred->uid);
             __get_user(cred->gid, &target_cred->gid);
+        } else if (cmsg->cmsg_level == SOL_ALG) {
+            uint32_t *dst = (uint32_t *)data;
+
+            memcpy(dst, target_data, len);
+            /* fix endianess of first 32-bit word */
+            if (len >= sizeof(uint32_t)) {
+                *dst = tswap32(*dst);
+            }
         } else {
             qemu_log_mask(LOG_UNIMP, "Unsupported ancillary data: %d/%d\n",
                           cmsg->cmsg_level, cmsg->cmsg_type);
-- 
2.39.1