return of the accept filter part II

accept filters are now loadable as well as able to be compiled into
the kernel.

two accept filters are provided, one that returns sockets when data
arrives the other when an http request is completed (doesn't work
with 0.9 requests)

Reviewed by: jmg

1 files changed, 101 insertions, 0 deletions

diff --git a/sys/kern/uipc_socket.c b/sys/kern/uipc_socket.c
index b172d46..c2d0ad7 100644
--- a/sys/kern/uipc_socket.c
+++ b/sys/kern/uipc_socket.c
@@ -58,6 +58,8 @@
 
 #include <machine/limits.h>
 
+static int	 do_setopt_accept_filter(struct socket *so, struct sockopt *sopt);
+
 static int 	filt_sorattach(struct knote *kn);
 static void 	filt_sordetach(struct knote *kn);
 static int 	filt_soread(struct knote *kn, long hint);
@@ -193,6 +195,15 @@ sodealloc(so)
 	if (so->so_snd.sb_hiwat)
 		(void)chgsbsize(so->so_cred->cr_uid,
 		    -(rlim_t)so->so_snd.sb_hiwat);
+	if (so->so_accf != NULL) {
+		if (so->so_accf->so_accept_filter != NULL && 
+			so->so_accf->so_accept_filter->accf_destroy != NULL) {
+			so->so_accf->so_accept_filter->accf_destroy(so);
+		}
+		if (so->so_accf->so_accept_filter_str != NULL)
+			FREE(so->so_accf->so_accept_filter_str, M_ACCF);
+		FREE(so->so_accf, M_ACCF);
+	}
 	crfree(so->so_cred);
 	zfreei(so->so_zone, so);
 }
@@ -977,6 +988,77 @@ sorflush(so)
 	sbrelease(&asb, so);
 }
 
+static int
+do_setopt_accept_filter(so, sopt)
+	struct	socket *so;
+	struct	sockopt *sopt;
+{
+	struct accept_filter_arg	*afap = NULL;
+	struct accept_filter	*afp;
+	struct so_accf	*af = so->so_accf;
+	int	error = 0;
+
+	/* removing the filter */
+	if (sopt == NULL) {
+		if (af != NULL) {
+			if (af->so_accept_filter != NULL && 
+				af->so_accept_filter->accf_destroy != NULL) {
+				af->so_accept_filter->accf_destroy(so);
+			}
+			if (af->so_accept_filter_str != NULL) {
+				FREE(af->so_accept_filter_str, M_ACCF);
+			}
+			FREE(af, M_ACCF);
+			so->so_accf = NULL;
+		}
+		so->so_options &= ~SO_ACCEPTFILTER;
+		return (0);
+	}
+	/* adding a filter */
+	/* must remove previous filter first */
+	if (af != NULL) {
+		error = EINVAL;
+		goto out;
+	}
+	/* don't put large objects on the kernel stack */
+	MALLOC(afap, struct accept_filter_arg *, sizeof(*afap), M_TEMP, M_WAITOK);
+	error = sooptcopyin(sopt, afap, sizeof *afap, sizeof *afap);
+	afap->af_name[sizeof(afap->af_name)-1] = '\0';
+	afap->af_arg[sizeof(afap->af_arg)-1] = '\0';
+	if (error)
+		goto out;
+	afp = accept_filt_get(afap->af_name);
+	if (afp == NULL) {
+		error = ENOENT;
+		goto out;
+	}
+	MALLOC(af, struct so_accf *, sizeof(*af), M_ACCF, M_WAITOK);
+	bzero(af, sizeof(*af));
+	if (afp->accf_create != NULL) {
+		if (afap->af_name[0] != '\0') {
+			int len = strlen(afap->af_name) + 1;
+
+			MALLOC(af->so_accept_filter_str, char *, len, M_ACCF, M_WAITOK);
+			strcpy(af->so_accept_filter_str, afap->af_name);
+		}
+		af->so_accept_filter_arg = afp->accf_create(so, afap->af_arg);
+		if (af->so_accept_filter_arg == NULL) {
+			FREE(af->so_accept_filter_str, M_ACCF);
+			FREE(af, M_ACCF);
+			so->so_accf = NULL;
+			error = EINVAL;
+			goto out;
+		}
+	}
+	af->so_accept_filter = afp;
+	so->so_accf = af;
+	so->so_options |= SO_ACCEPTFILTER;
+out:
+	if (afap != NULL)
+		FREE(afap, M_TEMP);
+	return (error);
+}
+
 /*
  * Perhaps this routine, and sooptcopyout(), below, ought to come in
  * an additional variant to handle the case where the option value needs
@@ -1137,6 +1219,11 @@ sosetopt(so, sopt)
 			}
 			break;
 
+		case SO_ACCEPTFILTER:
+			error = do_setopt_accept_filter(so, sopt);
+			if (error)
+				goto bad;
+			break;
 		default:
 			error = ENOPROTOOPT;
 			break;
@@ -1190,6 +1277,7 @@ sogetopt(so, sopt)
 	int	error, optval;
 	struct	linger l;
 	struct	timeval tv;
+	struct accept_filter_arg *afap;
 
 	error = 0;
 	if (sopt->sopt_level != SOL_SOCKET) {
@@ -1200,6 +1288,19 @@ sogetopt(so, sopt)
 			return (ENOPROTOOPT);
 	} else {
 		switch (sopt->sopt_name) {
+		case SO_ACCEPTFILTER:
+			MALLOC(afap, struct accept_filter_arg *, sizeof(*afap),
+				M_TEMP, M_WAITOK);
+			bzero(afap, sizeof(*afap));
+			if ((so->so_options & SO_ACCEPTFILTER) != 0) {
+				strcpy(afap->af_name, so->so_accf->so_accept_filter->accf_name);
+				if (so->so_accf->so_accept_filter_str != NULL)
+					strcpy(afap->af_arg, so->so_accf->so_accept_filter_str);
+			}
+			error = sooptcopyout(sopt, afap, sizeof(*afap));
+			FREE(afap, M_TEMP);
+			break;
+			
 		case SO_LINGER:
 			l.l_onoff = so->so_options & SO_LINGER;
 			l.l_linger = so->so_linger;