freebsd-dev/usr.sbin/ppp/loadalias.c
Brian Somers 6ed9fb2fc9 De-couple ppp from libalias. If libalias isn't there, the
alias commands simply won't work.  Only root may specify the
location of the alias lib (otherwise, it's hard-coded).

Make logprintf silently fail if LogOpen hasn't been called.

Suggested by:	eivind
1997-05-26 00:44:10 +00:00

89 lines
2.0 KiB
C

#include <sys/types.h>
#include <sys/socket.h>
#include <sys/param.h>
#include <netinet/in.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <dlfcn.h>
#include "systems.h"
#include "mbuf.h"
#include "log.h"
#include "loadalias.h"
#include "vars.h"
#define _PATH_ALIAS "/usr/lib/libalias.so.2.1"
#define off(item) ((int)&(((struct aliasHandlers *)0)->item))
#define entry(a) { off(a), "_" #a }
static struct {
int offset;
char *name;
} map[] = {
entry(GetNextFragmentPtr),
entry(GetNextFragmentPtr),
entry(InitPacketAlias),
entry(PacketAliasIn),
entry(PacketAliasOut),
entry(PacketAliasRedirectAddr),
entry(PacketAliasRedirectPort),
entry(SaveFragmentPtr),
entry(SetPacketAliasAddress),
entry(SetPacketAliasMode),
entry(FragmentAliasIn),
{ 0, 0 }
};
static void *dl;
int loadAliasHandlers(struct aliasHandlers *h)
{
char *path;
char *env;
char *err;
int i;
path = _PATH_ALIAS;
env = getenv("_PATH_ALIAS");
if (env)
if (OrigUid() == 0)
path = env;
else {
logprintf("Ignoring environment _PATH_ALIAS value (%s)\n", env);
printf("Ignoring environment _PATH_ALIAS value (%s)\n", env);
}
dl = dlopen(path, RTLD_LAZY);
if (dl == (void *)0) {
err = dlerror();
logprintf("_PATH_ALIAS (%s): Invalid lib: %s\n", path, err);
printf("_PATH_ALIAS (%s): Invalid lib: %s\n", path, err);
return -1;
}
for (i = 0; map[i].name; i++) {
*(void **)((char *)h + map[i].offset) = dlsym(dl, map[i].name);
if (*(void **)((char *)h + map[i].offset) == (void *)0) {
err = dlerror();
logprintf("_PATH_ALIAS (%s): %s: %s\n", path, map[i].name, err);
printf("_PATH_ALIAS (%s): %s: %s\n", path, map[i].name, err);
(void)dlclose(dl);
dl = (void *)0;
return -1;
}
}
VarInitPacketAlias();
return 0;
}
void unloadAliasHandlers()
{
if (dl) {
dlclose(dl);
dl = (void *)0;
}
}