From bb2f82724992fc35b433e9355112a98bf34e6244 Mon Sep 17 00:00:00 2001
From: Matthias Kruk <m@m10k.eu>
Date: Sat, 5 Oct 2019 15:32:37 +0900
Subject: [PATCH] Implement sys_getsockopt() and sys_setsockopt() functions

---
 kernel/core/cxnet.c | 88 ++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 84 insertions(+), 4 deletions(-)

diff --git a/kernel/core/cxnet.c b/kernel/core/cxnet.c
index c369d58..364996b 100644
--- a/kernel/core/cxnet.c
+++ b/kernel/core/cxnet.c
@@ -84,16 +84,96 @@ int sys_accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen)
 	return(-ENOSYS);
 }
 
-int sys_setsockopt(int sockfd, int level, int optname,
+int sys_setsockopt(int procfd, int level, int optname,
 				   const void *optval, socklen_t optlen)
 {
-	return(-ENOSYS);
+	process_t *cproc;
+	int sockfd;
+	int ret_val;
+
+	if(level != SOL_SOCKET) {
+		ret_val = -EINVAL;
+		goto gtfo;
+	}
+
+	ret_val = -EFAULT;
+	cproc = process_get_current();
+
+	if(cproc) {
+		sockfd = process_flookup(cproc, procfd);
+
+		if(sockfd < 0) {
+			ret_val = sockfd;
+		} else {
+			char koptbuf[128];
+			socklen_t koptlen;
+
+			/*
+			 * The memory referenced by `optval' is in the process's
+			 * address space, so we have to copy it into the kernel's
+			 * address space before being able to use it. Since the
+			 * process's buffer may sit on the boundary of two non-
+			 * consecutive pages, we can't just use the linear
+			 * address.
+			 */
+
+			koptlen = optlen < sizeof(koptbuf) ? optlen : sizeof(koptbuf);
+			process_memcpy_ptok(cproc, koptbuf, (void*)optval, koptlen);
+
+			ret_val = sosetopt(sockfd, optname, koptbuf, koptlen);
+		}
+	}
+
+gtfo:
+	return(ret_val);
 }
 
-int sys_getsockopt(int sockfd, int level, int optname,
+int sys_getsockopt(int procfd, int level, int optname,
 				   void *optval, socklen_t *optlen)
 {
-	return(-ENOSYS);
+	process_t *cproc;
+	int sockfd;
+	int ret_val;
+
+	/*
+	 * This function is essentially the same as sys_setsockopt(), except that it
+	 * calls sogetopt() instead of sosetopt(), and the buffer is copied after that
+	 * call, in the opposite direction.
+	 */
+
+	if(level != SOL_SOCKET) {
+		ret_val = -EINVAL;
+		goto gtfo;
+	}
+
+	ret_val = -EFAULT;
+	cproc = process_get_current();
+
+	if(cproc) {
+		sockfd = process_flookup(cproc, procfd);
+
+		if(sockfd < 0) {
+			ret_val = sockfd;
+		} else {
+			char koptbuf[128];
+			socklen_t koptlen;
+
+			koptlen = *optlen < sizeof(koptbuf) ? *optlen : sizeof(koptbuf);
+
+			ret_val = sogetopt(sockfd, optname, koptbuf, &koptlen);
+
+			if(!ret_val) {
+				/* return data to user-space if the call was successful */
+
+				process_memcpy_ktop(cproc, optval, koptbuf, koptlen);
+				/* as annoying (and unlikely) as it may be, optlen may also sit on a page-boundary */
+				process_memcpy_ktop(cproc, optlen, &koptlen, sizeof(koptlen));
+			}
+		}
+	}
+
+gtfo:
+	return(ret_val);
 }
 
 int sys_shutdown(int sockfd, int how)
-- 
2.47.3