Re: [akaros] [PATCH 1/4] add the capability device from Harvey (from Plan 9)
thanks Merged to master at 0b99538dc853..2644e0eb10fd (from, to] You can see the entire diff with 'git diff' or at https://github.com/brho/akaros/compare/0b99538dc853...2644e0eb10fd On 2016-10-14 at 13:26 Ronald G. Minnich wrote: > Change-Id: If159e72517809eedd0d1e98271e3dde57e035090 > Signed-off-by: Ronald G. Minnich -- You received this message because you are subscribed to the Google Groups "Akaros" group. To unsubscribe from this group and stop receiving emails from it, send an email to akaros+unsubscr...@googlegroups.com. To post to this group, send email to akaros@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[akaros] [PATCH 1/4] add the capability device from Harvey (from Plan 9)
Change-Id: If159e72517809eedd0d1e98271e3dde57e035090
Signed-off-by: Ronald G. Minnich
---
kern/drivers/dev/capability.c | 295 ++
1 file changed, 295 insertions(+)
create mode 100644 kern/drivers/dev/capability.c
diff --git a/kern/drivers/dev/capability.c b/kern/drivers/dev/capability.c
new file mode 100644
index 000..53a59af
--- /dev/null
+++ b/kern/drivers/dev/capability.c
@@ -0,0 +1,295 @@
+/*
+ * This file is part of the UCB release of Plan 9. It is subject to the license
+ * terms in the LICENSE file found in the top-level directory of this
+ * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
+ * part of the UCB release of Plan 9, including this file, may be copied,
+ * modified, propagated, or distributed except according to the terms contained
+ * in the LICENSE file.
+ */
+
+#include "u.h"
+#include "../port/lib.h"
+#include "mem.h"
+#include "dat.h"
+#include "fns.h"
+#include "../port/error.h"
+
+#include
+
+enum
+{
+ Hashlen=SHA1dlen,
+ Maxhash=256,
+};
+
+/*
+ * if a process knows cap->cap, it can change user
+ * to capabilty->user.
+ */
+typedef struct Caphash Caphash;
+struct Caphash
+{
+ Caphash *next;
+ charhash[Hashlen];
+};
+
+struct
+{
+ QLock QLock;
+ Caphash *first;
+ int nhash;
+} capalloc;
+
+enum
+{
+ Qdir,
+ Qhash,
+ Quse,
+};
+
+/* caphash must be last */
+Dirtab capdir[] =
+{
+ ".",{Qdir,0,QTDIR}, 0, DMDIR|0500,
+ "capuse", {Quse}, 0, 0222,
+ "caphash", {Qhash},0, 0200,
+};
+int ncapdir = nelem(capdir);
+
+static Chan*
+capattach(char *spec)
+{
+ return devattach(L'¤', spec);
+}
+
+static Walkqid*
+capwalk(Chan *c, Chan *nc, char **name, int nname)
+{
+ return devwalk(c, nc, name, nname, capdir, ncapdir, devgen);
+}
+
+static void
+capremove(Chan *c)
+{
+ if(iseve() && c->qid.path == Qhash)
+ ncapdir = nelem(capdir)-1;
+ else
+ error(Eperm);
+}
+
+
+static int32_t
+capstat(Chan *c, uint8_t *db, int32_t n)
+{
+ return devstat(c, db, n, capdir, ncapdir, devgen);
+}
+
+/*
+ * if the stream doesn't exist, create it
+ */
+static Chan*
+capopen(Chan *c, int omode)
+{
+ if(c->qid.type & QTDIR){
+ if(omode != OREAD)
+ error(Ebadarg);
+ c->mode = omode;
+ c->flag |= COPEN;
+ c->offset = 0;
+ return c;
+ }
+
+ switch((uint32_t)c->qid.path){
+ case Qhash:
+ if(!iseve())
+ error(Eperm);
+ break;
+ }
+
+ c->mode = openmode(omode);
+ c->flag |= COPEN;
+ c->offset = 0;
+ return c;
+}
+
+/*
+static char*
+hashstr(uchar *hash)
+{
+ static char buf[2*Hashlen+1];
+ int i;
+
+ for(i = 0; i < Hashlen; i++)
+ sprint(buf+2*i, "%2.2x", hash[i]);
+ buf[2*Hashlen] = 0;
+ return buf;
+}
+ */
+
+static Caphash*
+remcap(uint8_t *hash)
+{
+ Caphash *t, **l;
+
+ qlock(&capalloc.QLock);
+
+ /* find the matching capability */
+ for(l = &capalloc.first; *l != nil;){
+ t = *l;
+ if(memcmp(hash, t->hash, Hashlen) == 0)
+ break;
+ l = &t->next;
+ }
+ t = *l;
+ if(t != nil){
+ capalloc.nhash--;
+ *l = t->next;
+ }
+ qunlock(&capalloc.QLock);
+
+ return t;
+}
+
+/* add a capability, throwing out any old ones */
+static void
+addcap(uint8_t *hash)
+{
+ Caphash *p, *t, **l;
+
+ p = smalloc(sizeof *p);
+ memmove(p->hash, hash, Hashlen);
+ p->next = nil;
+
+ qlock(&capalloc.QLock);
+
+ /* trim extras */
+ while(capalloc.nhash >= Maxhash){
+ t = capalloc.first;
+ if(t == nil)
+ panic("addcap");
+ capalloc.first = t->next;
+ free(t);
+ capalloc.nhash--;
+ }
+
+ /* add new one */
+ for(l = &capalloc.first; *l != nil; l = &(*l)->next)
+ ;
+ *l = p;
+ capalloc.nhash++;
+
+ qunlock(&capalloc.QLock);
+}
+
+static void
+capclose(Chan* c)
+{
+}
+
+static int32_t
+capread(Chan *c, void *va, int32_t n, int64_t m)
+{
+ switch((uint32_t)c->qid.path){
+ case Qdir:
+ return devdirread(c, va, n, capdir, ncapdir, devgen);
+
+ default:
+ error(Eperm);
+ break;
+ }
+ return n;
+}
+
+static int32_t
+capwrite(Chan *c, void *va, int32_t n, int64_t m)
+{
+ Caphash *p;
+ char *cp;
+ uint8_t hash[Hashlen];
+ char *key, *from, *to;
+ char err[256];
+ Proc *up = externup();
+
+ switch((uint32_t)c->qid.path){
+
[akaros] [PATCH 1/4] add the capability device from Harvey (from Plan 9)
Change-Id: If159e72517809eedd0d1e98271e3dde57e035090
Signed-off-by: Ronald G. Minnich
---
kern/drivers/dev/capability.c | 295 ++
1 file changed, 295 insertions(+)
create mode 100644 kern/drivers/dev/capability.c
diff --git a/kern/drivers/dev/capability.c b/kern/drivers/dev/capability.c
new file mode 100644
index 000..53a59af
--- /dev/null
+++ b/kern/drivers/dev/capability.c
@@ -0,0 +1,295 @@
+/*
+ * This file is part of the UCB release of Plan 9. It is subject to the license
+ * terms in the LICENSE file found in the top-level directory of this
+ * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
+ * part of the UCB release of Plan 9, including this file, may be copied,
+ * modified, propagated, or distributed except according to the terms contained
+ * in the LICENSE file.
+ */
+
+#include "u.h"
+#include "../port/lib.h"
+#include "mem.h"
+#include "dat.h"
+#include "fns.h"
+#include "../port/error.h"
+
+#include
+
+enum
+{
+ Hashlen=SHA1dlen,
+ Maxhash=256,
+};
+
+/*
+ * if a process knows cap->cap, it can change user
+ * to capabilty->user.
+ */
+typedef struct Caphash Caphash;
+struct Caphash
+{
+ Caphash *next;
+ charhash[Hashlen];
+};
+
+struct
+{
+ QLock QLock;
+ Caphash *first;
+ int nhash;
+} capalloc;
+
+enum
+{
+ Qdir,
+ Qhash,
+ Quse,
+};
+
+/* caphash must be last */
+Dirtab capdir[] =
+{
+ ".",{Qdir,0,QTDIR}, 0, DMDIR|0500,
+ "capuse", {Quse}, 0, 0222,
+ "caphash", {Qhash},0, 0200,
+};
+int ncapdir = nelem(capdir);
+
+static Chan*
+capattach(char *spec)
+{
+ return devattach(L'¤', spec);
+}
+
+static Walkqid*
+capwalk(Chan *c, Chan *nc, char **name, int nname)
+{
+ return devwalk(c, nc, name, nname, capdir, ncapdir, devgen);
+}
+
+static void
+capremove(Chan *c)
+{
+ if(iseve() && c->qid.path == Qhash)
+ ncapdir = nelem(capdir)-1;
+ else
+ error(Eperm);
+}
+
+
+static int32_t
+capstat(Chan *c, uint8_t *db, int32_t n)
+{
+ return devstat(c, db, n, capdir, ncapdir, devgen);
+}
+
+/*
+ * if the stream doesn't exist, create it
+ */
+static Chan*
+capopen(Chan *c, int omode)
+{
+ if(c->qid.type & QTDIR){
+ if(omode != OREAD)
+ error(Ebadarg);
+ c->mode = omode;
+ c->flag |= COPEN;
+ c->offset = 0;
+ return c;
+ }
+
+ switch((uint32_t)c->qid.path){
+ case Qhash:
+ if(!iseve())
+ error(Eperm);
+ break;
+ }
+
+ c->mode = openmode(omode);
+ c->flag |= COPEN;
+ c->offset = 0;
+ return c;
+}
+
+/*
+static char*
+hashstr(uchar *hash)
+{
+ static char buf[2*Hashlen+1];
+ int i;
+
+ for(i = 0; i < Hashlen; i++)
+ sprint(buf+2*i, "%2.2x", hash[i]);
+ buf[2*Hashlen] = 0;
+ return buf;
+}
+ */
+
+static Caphash*
+remcap(uint8_t *hash)
+{
+ Caphash *t, **l;
+
+ qlock(&capalloc.QLock);
+
+ /* find the matching capability */
+ for(l = &capalloc.first; *l != nil;){
+ t = *l;
+ if(memcmp(hash, t->hash, Hashlen) == 0)
+ break;
+ l = &t->next;
+ }
+ t = *l;
+ if(t != nil){
+ capalloc.nhash--;
+ *l = t->next;
+ }
+ qunlock(&capalloc.QLock);
+
+ return t;
+}
+
+/* add a capability, throwing out any old ones */
+static void
+addcap(uint8_t *hash)
+{
+ Caphash *p, *t, **l;
+
+ p = smalloc(sizeof *p);
+ memmove(p->hash, hash, Hashlen);
+ p->next = nil;
+
+ qlock(&capalloc.QLock);
+
+ /* trim extras */
+ while(capalloc.nhash >= Maxhash){
+ t = capalloc.first;
+ if(t == nil)
+ panic("addcap");
+ capalloc.first = t->next;
+ free(t);
+ capalloc.nhash--;
+ }
+
+ /* add new one */
+ for(l = &capalloc.first; *l != nil; l = &(*l)->next)
+ ;
+ *l = p;
+ capalloc.nhash++;
+
+ qunlock(&capalloc.QLock);
+}
+
+static void
+capclose(Chan* c)
+{
+}
+
+static int32_t
+capread(Chan *c, void *va, int32_t n, int64_t m)
+{
+ switch((uint32_t)c->qid.path){
+ case Qdir:
+ return devdirread(c, va, n, capdir, ncapdir, devgen);
+
+ default:
+ error(Eperm);
+ break;
+ }
+ return n;
+}
+
+static int32_t
+capwrite(Chan *c, void *va, int32_t n, int64_t m)
+{
+ Caphash *p;
+ char *cp;
+ uint8_t hash[Hashlen];
+ char *key, *from, *to;
+ char err[256];
+ Proc *up = externup();
+
+ switch((uint32_t)c->qid.path){
+
