Module Name: src
Committed By: pooka
Date: Fri Feb 18 11:41:33 UTC 2011
Modified Files:
src/lib/librumphijack: hijack.c
Log Message:
Use the env variable RUMPHIJACK to specify what facilities should
be hijacked. If it's not specified, the default is
"path=/rump,socket=all:nolocal".
So, if you're moof and want to relive your domain/os days (??),
you can do this:
pain-rustique:51:~> setenv RUMPHIJACK 'path=//'
pain-rustique:52:~> df //dev
Filesystem 1K-blocks Used Avail %Cap Mounted on
rumpfs 1 1 0 100% /
pain-rustique:53:~> df /dev
Filesystem 1K-blocks Used Avail %Cap Mounted on
/dev/wd0a 1019864 280640 688232 28% /
To generate a diff of this commit:
cvs rdiff -u -r1.48 -r1.49 src/lib/librumphijack/hijack.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/lib/librumphijack/hijack.c
diff -u src/lib/librumphijack/hijack.c:1.48 src/lib/librumphijack/hijack.c:1.49
--- src/lib/librumphijack/hijack.c:1.48 Thu Feb 17 17:18:08 2011
+++ src/lib/librumphijack/hijack.c Fri Feb 18 11:41:32 2011
@@ -1,4 +1,4 @@
-/* $NetBSD: hijack.c,v 1.48 2011/02/17 17:18:08 pooka Exp $ */
+/* $NetBSD: hijack.c,v 1.49 2011/02/18 11:41:32 pooka Exp $ */
/*-
* Copyright (c) 2011 Antti Kantee. All Rights Reserved.
@@ -26,7 +26,7 @@
*/
#include <sys/cdefs.h>
-__RCSID("$NetBSD: hijack.c,v 1.48 2011/02/17 17:18:08 pooka Exp $");
+__RCSID("$NetBSD: hijack.c,v 1.49 2011/02/18 11:41:32 pooka Exp $");
#define __ssp_weak_name(fun) _hijack_ ## fun
@@ -300,15 +300,124 @@
return (void *)rv;
}
-static int pwdinrump = 0;
+/*
+ * This tracks if our process is in a subdirectory of /rump.
+ * It's preserved over exec.
+ */
+static bool pwdinrump = false;
+
+/*
+ * These variables are set from the RUMPHIJACK string and control
+ * which operations can product rump kernel file descriptors.
+ * This should be easily extendable for future needs.
+ */
+#define RUMPHIJACK_DEFAULT "path=/rump,socket=all:nolocal"
+static bool rumpsockets[PF_MAX];
+static const char *rumpprefix;
+static size_t rumpprefixlen;
+
+static struct {
+ int pf;
+ const char *name;
+} socketmap[] = {
+ { PF_INET, "inet" },
+ { PF_LINK, "link" },
+ { PF_ROUTE, "route" },
+ { PF_INET6, "inet6" },
+ { -1, NULL }
+};
+
+static void
+sockparser(char *buf)
+{
+ char *p, *l;
+ bool value;
+ int i;
+
+ /* if "all" is present, it must be specified first */
+ if (strncmp(buf, "all", strlen("all")) == 0) {
+ for (i = 0; i < __arraycount(rumpsockets); i++) {
+ rumpsockets[i] = true;
+ }
+ buf += strlen("all");
+ if (*buf == ':')
+ buf++;
+ }
+
+ for (p = strtok_r(buf, ":", &l); p; p = strtok_r(NULL, ":", &l)) {
+ value = true;
+ if (strncmp(p, "no", strlen("no")) == 0) {
+ value = false;
+ p += strlen("no");
+ }
-/* low calorie sockets? */
-static bool hostlocalsockets = true;
+ for (i = 0; socketmap[i].name; i++) {
+ if (strcmp(p, socketmap[i].name) == 0) {
+ rumpsockets[socketmap[i].pf] = value;
+ break;
+ }
+ }
+ if (socketmap[i].name == NULL) {
+ warnx("invalid socket specifier %s", p);
+ }
+ }
+}
+
+static void
+pathparser(char *buf)
+{
+
+ if (*buf != '/')
+ errx(1, "hijack path specifier must begin with ``/''");
+
+ if ((rumpprefix = strdup(buf)) == NULL)
+ err(1, "strdup");
+ rumpprefixlen = strlen(rumpprefix);
+}
+
+static struct {
+ void (*parsefn)(char *);
+ const char *name;
+} hijackparse[] = {
+ { sockparser, "socket" },
+ { pathparser, "path" },
+ { NULL, NULL },
+};
+
+static void
+parsehijack(char *hijack)
+{
+ char *p, *p2, *l;
+ const char *hijackcopy;
+ int i;
+
+ if ((hijackcopy = strdup(hijack)) == NULL)
+ err(1, "strdup");
+
+ /* disable everything explicitly */
+ for (i = 0; i < PF_MAX; i++)
+ rumpsockets[i] = false;
+
+ for (p = strtok_r(hijack, ",", &l); p; p = strtok_r(NULL, ",", &l)) {
+ p2 = strchr(p, '=');
+ if (!p2)
+ errx(1, "invalid hijack specifier: %s", hijackcopy);
+
+ for (i = 0; hijackparse[i].parsefn; i++) {
+ if (strncmp(hijackparse[i].name, p,
+ (size_t)(p2-p)) == 0) {
+ hijackparse[i].parsefn(p2+1);
+ break;
+ }
+ }
+ }
+
+}
static void __attribute__((constructor))
rcinit(void)
{
- char buf[64];
+ char buf[1024];
extern void *(*rumpclient_dlsym)(void *, const char *);
unsigned i, j;
@@ -349,6 +458,12 @@
if (rumpclient_init() == -1)
err(1, "rumpclient init");
+ /* check which syscalls we're supposed to hijack */
+ if (getenv_r("RUMPHIJACK", buf, sizeof(buf)) == -1) {
+ strcpy(buf, RUMPHIJACK_DEFAULT);
+ }
+ parsehijack(buf);
+
/* set client persistence level */
if (getenv_r("RUMPHIJACK_RETRYCONNECT", buf, sizeof(buf)) != -1) {
if (strcmp(buf, "die") == 0)
@@ -375,7 +490,7 @@
unsetenv("RUMPHIJACK__DUP2MASK");
}
if (getenv_r("RUMPHIJACK__PWDINRUMP", buf, sizeof(buf)) == 0) {
- pwdinrump = strtoul(buf, NULL, 10);
+ pwdinrump = true;
unsetenv("RUMPHIJACK__PWDINRUMP");
}
}
@@ -413,15 +528,17 @@
#define assertfd(_fd_) assert(ISDUP2D(_fd_) || (_fd_) >= HIJACK_FDOFF)
-#define RUMPPREFIX "/rump"
-static int
+static bool
path_isrump(const char *path)
{
+ if (rumpprefix == NULL)
+ return false;
+
if (*path == '/') {
- if (strncmp(path, RUMPPREFIX, sizeof(RUMPPREFIX)-1) == 0)
- return 1;
- return 0;
+ if (strncmp(path, rumpprefix, rumpprefixlen) == 0)
+ return true;
+ return false;
} else {
return pwdinrump;
}
@@ -434,7 +551,7 @@
const char *rv;
if (*path == '/') {
- rv = path + (sizeof(RUMPPREFIX)-1);
+ rv = path + rumpprefixlen;
if (*rv == '\0')
rv = rootpath;
} else {
@@ -577,17 +694,17 @@
{
int (*op_socket)(int, int, int);
int fd;
- bool dohost;
+ bool isrump;
- dohost = hostlocalsockets && (domain == AF_LOCAL);
+ isrump = domain < PF_MAX && rumpsockets[domain];
- if (dohost)
- op_socket = GETSYSCALL(host, SOCKET);
- else
+ if (isrump)
op_socket = GETSYSCALL(rump, SOCKET);
+ else
+ op_socket = GETSYSCALL(host, SOCKET);
fd = op_socket(domain, type, protocol);
- if (!dohost)
+ if (isrump)
fd = fd_rump2host(fd);
else
fd = fd_dupgood(fd);
@@ -874,7 +991,7 @@
{
char buf[128];
char *dup2str;
- char *pwdinrumpstr;
+ const char *pwdinrumpstr;
char **newenv;
size_t nelem;
int rv, sverrno;
@@ -892,14 +1009,7 @@
}
if (pwdinrump) {
- snprintf(buf, sizeof(buf), "RUMPHIJACK__PWDINRUMP=%u",
- pwdinrump);
- pwdinrumpstr = malloc(strlen(buf)+1);
- if (pwdinrumpstr == NULL) {
- free(dup2str);
- return ENOMEM;
- }
- strcpy(pwdinrumpstr, buf);
+ pwdinrumpstr = "RUMPHIJACK__PWDINRUMP=true";
bonus++;
} else {
pwdinrumpstr = NULL;
@@ -910,7 +1020,6 @@
newenv = malloc(sizeof(*newenv) * nelem+bonus);
if (newenv == NULL) {
free(dup2str);
- free(pwdinrumpstr);
return ENOMEM;
}
memcpy(newenv, envp, nelem*sizeof(*newenv));
@@ -919,7 +1028,7 @@
i++;
}
if (pwdinrumpstr) {
- newenv[nelem+i] = pwdinrumpstr;
+ newenv[nelem+i] = __UNCONST(pwdinrumpstr);
i++;
}
newenv[nelem+i] = NULL;
