# include <config.h>
#endif
+#include "pathconfig.h"
+#include "util.h"
+
+#include <vserver.h>
+
#include <dlfcn.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdio.h>
#include <unistd.h>
+#include <asm/unistd.h>
#include <string.h>
#include <stdbool.h>
#include <errno.h>
-#include <asm/unistd.h>
#include <fcntl.h>
#include <stdarg.h>
#include <sys/mount.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/wait.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <fcntl.h>
+#include <pwd.h>
+#include <grp.h>
+
+#ifndef CLONE_NEWNS
+# define CLONE_NEWNS 0x00020000
+#endif
#define LIBNAME "rpm-fake.so"
#define PLATFORM_FILE "/etc/rpm/platform"
-#define INIT(FILE,FUNC) FUNC##_func = ((__typeof__(FUNC) *) (dlsym(FILE, #FUNC)))
+#define INIT(FILE,FUNC) FUNC##_func = ((__typeof__(FUNC) *) (xdlsym(FILE, #FUNC)))
#define DECLARE(FUNC) static __typeof__(FUNC) * FUNC##_func = 0
-static bool is_initialized = false;
-DECLARE(execv);
- //DECLARE(open);
-
-static int def_NR_new_s_context = 259;
-#undef __NR_new_s_context
-static int __NR_new_s_context_rev0;
-static int __NR_new_s_context_rev1;
-static int new_s_context_rev0(int, int, int);
-static int new_s_context_rev1(int, int *, int, int);
+#define DBG_INIT 0x0001
+#define DBG_VARIABLES 0x0002
+#define DBG_RESOLVER 0x0004
+#define DBG_EXECV 0x0008
+#define DBG_VERBOSE0 0x8000
+#define DBG_VERBOSE1 (0x4000 | DBG_VERBOSE0)
+#define DBG_VERBOSE2 (0x2000 | DBG_VERBOSE1)
+
+static char const * ctx_s = 0;
+static xid_t ctx = VC_NOCTX;
+static uint32_t caps = ~0;
+static int flags = 0;
+static char const * mnts = 0;
+static char const * root = 0;
+static int pw_sock = -1;
+static int sync_sock = -1;
+static unsigned int debug_level = 0;
-_syscall3(int, new_s_context_rev0, int, newctx, int, remove_cap, int, flags)
-_syscall4(int, new_s_context_rev1, int, nbctx, int *, ctxs, int, remove_cap, int, flags)
-
-static int
-new_s_context(int rev,
- int nbctx, int *ctxs, int remove_cap, int flags)
-{
- int ret;
-
- switch (rev) {
- case 0 :
- {
- int ctx;
-
- switch (nbctx) {
- case 0 : ctx = -1; break;
- case 1 : ctx = ctxs[0]; break;
- default : errno = EINVAL; return -1;
- }
+static bool is_initialized = false;
- ret = new_s_context_rev0(ctx, remove_cap, flags);
+DECLARE(execv);
+DECLARE(getpwnam);
+DECLARE(getgrnam);
+DECLARE(endpwent);
+DECLARE(endgrent);
- break;
- }
+static void initRPMFake() __attribute__((__constructor__));
+static void exitRPMFake() __attribute__((__destructor__));
- case 1 :
- ret = new_s_context_rev1(nbctx, ctxs, remove_cap, flags);
- break;
+static inline bool
+isDbgLevel(unsigned int level)
+{
+ return ((debug_level&level)==level);
+}
- default :
- errno = EINVAL; return -1;
+static void *
+xdlsym(void *handle, const char *symbol)
+{
+ void *res = dlsym(handle, symbol);
+ if (res==0) {
+ char const *error = dlerror();
+ write(2, symbol, strlen(symbol));
+ write(2, ": ", 2);
+ write(2, error, strlen(error));
+ write(2, "\n", 2);
+
+ _exit(255);
}
- return ret;
+ return res;
}
static void
-initVserverSyscalls(int s_context_NR)
+showHelp()
{
- int nr = (s_context_NR!=-1) ? s_context_NR : def_NR_new_s_context;
+ WRITE_MSG(1,
+ "Usage: LD_PRELOAD=" LIBNAME " <executable> <args>*\n\n"
+ LIBNAME " unterstands the following environment variables:\n"
+ " $RPM_FAKE_RESOLVER ... program which does the NSS resolving (defaults\n"
+ " to " RESOLVER_PROG ")\n"
+ " $RPM_FAKE_RESOLVER_UID ... uid of the resolver program\n"
+ " $RPM_FAKE_RESOLVER_GID ... gid of the resolver program\n"
+ " $RPM_FAKE_CTX ... vserver context which shall be used for resolver\n"
+ " and scriptlets\n"
+ " $RPM_FAKE_CAP ... linux capability remove-mask for the context\n"
+ " $RPM_FAKE_FLAGS ... vserver flags of the context\n"
+ " $RPM_FAKE_CHROOT ... directory of the chroot environment\n"
+ " $RPM_FAKE_NAMESPACE_MOUNTS\n"
+ " ... colon separated list of directories which will\n"
+ " umounted before scriptlet execution\n\n"
+ " $RPM_FAKE_HELP ... shows this message\n"
+ " $RPM_FAKE_VERSION ... shows the version of this program\n\n"
+ " $RPM_FAKE_DEBUG ... sets the debuglevel bitmask\n\n"
+ "Please report bugs to " PACKAGE_BUGREPORT "\n");
+ exit(0);
+}
- __NR_new_s_context_rev0 = __NR_new_s_context_rev1 = nr;
+static void
+showVersion()
+{
+ WRITE_MSG(1,
+ LIBNAME " " VERSION " -- wrapper around rpm\n"
+ "This program is part of " PACKAGE_STRING "\n\n"
+ "Copyright (C) 2003 Enrico Scholz\n"
+ VERSION_COPYRIGHT_DISCLAIMER);
+ exit(0);
}
static int
getAndClearEnv(char const *key, int dflt)
{
- char *env = getenv(key);
+ char *env = getenv(key);
int res;
if (env==0 || env[0]=='\0') res = dflt;
return res;
}
+#if 0
+static void
+initPwSocket()
+{
+ char const * sock_name = getenv("RPM_FAKE_PWSOCKET");
+ if (sock_name!=0) {
+ int flag;
+ struct sockaddr_un addr = {
+ .sun_family = AF_UNIX,
+ };
+
+ strncpy(addr.sun_path, sock_name, sizeof(addr.sun_path)-1);
+ addr.sun_path[sizeof(addr.sun_path)-1]='\0';
+
+ if ((pw_sock=socket(AF_UNIX, SOCK_STREAM, 0))==-1 ||
+ connect(pw_sock, (struct sockaddr *)(&addr), sizeof addr)==-1 ||
+ (flag=fcntl(pw_sock, F_GETFD))==-1 ||
+ fcntl(pw_sock, F_SETFD, flag | FD_CLOEXEC)==-1) {
+ perror("error while initializing pw-socket");
+ exit(255);
+ }
+ }
+ unsetenv("RPM_FAKE_PWSOCKET");
+}
+#else
+static void
+initPwSocket()
+{
+ char const * resolver = getenv("RPM_FAKE_RESOLVER");
+ if (resolver==0) resolver=RESOLVER_PROG;
+
+ if (resolver!=0 && *resolver!='\0') {
+ int res_sock[2];
+ int sync_pipe[2];
+ pid_t pid;
+ char const * uid=0;
+ char const * gid=0;
+
+ uid=getenv("RPM_FAKE_RESOLVER_UID");
+ gid=getenv("RPM_FAKE_RESOLVER_GID");
+
+ if (socketpair(AF_UNIX, SOCK_STREAM, 0, res_sock)==-1 ||
+ pipe(sync_pipe)==-1 ||
+ fcntl(res_sock[0], F_SETFD, FD_CLOEXEC)==-1 ||
+ fcntl(sync_pipe[0], F_SETFD, FD_CLOEXEC)==-1) {
+ perror("rpm-fake.so: failed to create/initialize resolver-socket or pipe");
+ exit(255);
+ }
+
+ pid = fork();
+ if (pid==-1) {
+ perror("rpm-fake.so: fork()");
+ exit(255);
+ }
+
+ if (pid==0) {
+ char const *args[10];
+ char const **ptr = args;
+ char const *env[] = { "HOME=/", "PATH=/bin:/usr/bin", 0 };
+
+ setsid();
+ dup2(res_sock[1], 0);
+ dup2(res_sock[1], 1);
+ dup2(sync_pipe[1], 2);
+ close(sync_pipe[1]);
+ close(res_sock[1]);
+ /* ... *socket[0] are marked as close-on-exec ...*/
+
+ *ptr++ = resolver;
+ if (root) { *ptr++ = "-r"; *ptr++ = root; }
+ if (uid) { *ptr++ = "-u"; *ptr++ = uid; }
+ if (gid) { *ptr++ = "-g"; *ptr++ = gid; }
+ if (ctx_s) { *ptr++ = "-c"; *ptr++ = ctx_s; }
+ *ptr++ = 0;
+
+ execve(resolver, (char **)args, (char **)env);
+ perror("rpm-fake.so: failed to exec resolver");
+ exit(255);
+ }
+ else {
+ uint8_t c;
+
+ close(res_sock[1]);
+ close(sync_pipe[1]);
+ pw_sock = res_sock[0];
+ sync_sock = sync_pipe[0];
+
+ if (read(sync_sock, &c, 1)!=1 ||
+ write(pw_sock, ".", 1)!=1 ||
+ read(pw_sock, &c, 1)!=1 ||
+ c!='.') {
+ WRITE_MSG(2, "rpm-fake.so: failed to initialize communication with resolver");
+ exit(255);
+ }
+ }
+
+ free((char *)ctx_s);
+ unsetenv("RPM_FAKE_RESOLVER_GID");
+ unsetenv("RPM_FAKE_RESOLVER_UID");
+ unsetenv("RPM_FAKE_RESOLVER");
+ }
+}
+#endif
+
static void
-initLib()
+initEnvironment()
{
+ int syscall_rev;
+ int syscall_nr;
+
if (is_initialized) return;
- initVserverSyscalls(getAndClearEnv("RPM_FAKE_S_CONTEXT_NR", -1));
- INIT(RTLD_NEXT, execv);
- //INIT(RTLD_NEXT, open);
+ syscall_rev = getAndClearEnv("RPM_FAKE_S_CONTEXT_REV", 0);
+ syscall_nr = getAndClearEnv("RPM_FAKE_S_CONTEXT_NR", 273);
+
+#ifdef VC_ENABLE_API_LEGACY
+ {
+ extern void vc_init_internal_legacy(int ctx_rev, int ctx_number,
+ int ipv4_rev, int ipv4_number);
+
+ vc_init_internal_legacy(syscall_rev, syscall_nr, 3, 274);
+ }
+#endif
+
+ ctx_s = getenv("RPM_FAKE_CTX");
+ if (ctx_s) ctx_s = strdup(ctx_s);
+
+ ctx = getAndClearEnv("RPM_FAKE_CTX", VC_RANDCTX);
+ caps = getAndClearEnv("RPM_FAKE_CAP", ~0x3404040f);
+ flags = getAndClearEnv("RPM_FAKE_FLAGS", 0);
+ root = getenv("RPM_FAKE_CHROOT");
+ mnts = getenv("RPM_FAKE_NAMESPACE_MOUNTS");
+ if (mnts!=0) mnts = strdup(mnts);
+ unsetenv("RPM_FAKE_CHROOT");
+ unsetenv("RPM_FAKE_NAMESPACE_MOUNTS");
+
+
is_initialized = true;
}
static void
+initSymbols()
+{
+ INIT(RTLD_NEXT, execv);
+ INIT(RTLD_NEXT, getgrnam);
+ INIT(RTLD_NEXT, getpwnam);
+ INIT(RTLD_NEXT, endpwent);
+ INIT(RTLD_NEXT, endgrent);
+}
+
+static void
fixPreloadEnv()
{
char *env = getenv("LD_PRELOAD");
char *pos;
- // the const <-> non-const assignment is not an issue since the following modifying operations
- // will not be executed in the const-case
+ // the const <-> non-const assignment is not an issue since the following
+ // modifying operations will not be executed in the const-case
env = env ? env : "";
pos = strstr(env, LIBNAME);
char *end_pos = pos + sizeof(LIBNAME);
bool is_end = (end_pos[-1]=='\0');
char *start_pos;
-
+
end_pos[-1] = '\0';
start_pos = strrchr(env, ':');
if (start_pos==0) start_pos = env;
}
#ifdef DEBUG
- printf("env='%s'\n", env);
+ if (isDbgLevel(DBG_VERBOSE1|DBG_VARIABLES)) {
+ WRITE_MSG(2, "env='");
+ WRITE_STR(2, env);
+ WRITE_MSG(2, "'\n");
+ }
#endif
if (*env=='\0') unsetenv("LD_PRELOAD");
}
+void
+initRPMFake()
+{
+ if (getenv("RPM_FAKE_VERSION")) showVersion();
+ if (getenv("RPM_FAKE_HELP")) showHelp();
+
+ debug_level = getAndClearEnv("RPM_FAKE_DEBUG", 0);
+
+ if (isDbgLevel(DBG_INIT)) WRITE_MSG(2, ">>>>> initRPMFake <<<<<\n");
+
+ fixPreloadEnv();
+ initSymbols();
+ initEnvironment();
+ initPwSocket();
+
+#if 0
+ if (isDbgLevel(DBG_VARIABLES|DBG_VERBOSE2)) {
+
+ }
+#endif
+}
+
+void
+exitRPMFake()
+{
+ write(2, ">>>>> exitRPMFake <<<<<\n", 24);
+ if (pw_sock!=-1) {
+ uint8_t c;
+ read(sync_sock, &c, 1);
+ write(pw_sock, "Q", 1);
+ }
+}
+
+
+ //============ the worker part ===========
+
+
+static bool
+doPwStringRequest(uint32_t *result, char style, char const *name)
+{
+ uint32_t len = strlen(name);
+ uint8_t code;
+ uint8_t c;
+
+ // read the token...
+ read(sync_sock, &c, 1);
+
+ write(pw_sock, &style, 1);
+ write(pw_sock, &len, sizeof len);
+ write(pw_sock, name, len);
+ read (pw_sock, &code, sizeof code);
+ read (pw_sock, result, sizeof *result);
+
+ return code!=0;
+}
+
+struct passwd *
+getpwnam(const char * name)
+{
+ if (pw_sock==-1) return getpwnam_func(name);
+ else {
+ static struct passwd res = {
+ .pw_passwd = "*",
+ .pw_gid = -1,
+ .pw_gecos = "",
+ .pw_dir = "/",
+ .pw_shell = "/bin/false"
+ };
+
+ res.pw_name = (char *)(name);
+ if (!doPwStringRequest(&res.pw_uid, 'P', name)) return 0;
+
+ return &res;
+ }
+}
+
+struct group *
+getgrnam(const char * name)
+{
+ if (pw_sock==-1) return getgrnam_func(name);
+ else {
+ static struct group res = {
+ .gr_passwd = "*",
+ .gr_mem = 0
+ };
+
+ res.gr_name = (char *)(name);
+ if (!doPwStringRequest(&res.gr_gid, 'G', name)) return 0;
+
+ return &res;
+ }
+}
+
+void
+endgrent()
+{
+ if (pw_sock==-1) endgrent_func();
+}
+
+void
+endpwent()
+{
+ if (pw_sock==-1) endpwent_func();
+}
+
+
static int
execvWorker(char const *path, char * const argv[])
{
int res;
- int ctx;
- ctx = getAndClearEnv("RPM_FAKE_CTX", -1);
- if ( (res=new_s_context(getAndClearEnv("RPM_FAKE_S_CONTEXT_REV", 0),
- ctx==-1 ? 0 : 1,
- &ctx,
- getAndClearEnv("RPM_FAKE_CAP", ~0x3404040f),
- getAndClearEnv("RPM_FAKE_FLAGS", 0)))!=-1 &&
- (res=execv_func(path, argv)!=-1) ) {}
+ if ((res=vc_new_s_context(ctx,caps,flags))!=-1 &&
+ (res=execv_func(path, argv)!=-1) ) {}
return res;
}
};
static int
-removeNamespaceMountsChild(void *params_v)
+removeNamespaceMountsChild(struct ExecvParams const *params)
{
- struct ExecvParams * params = params_v;
char buf[strlen(params->mnts)+1], *ptr;
strcpy(buf, params->mnts);
ptr = strtok(0, ":");
}
- unsetenv("RPM_FAKE_NAMESPACE_MOUNTS");
return execvWorker(params->path, params->argv);
}
static int
removeNamespaceMounts(char const *path, char * const argv[])
{
- char const * mnts = getenv("RPM_FAKE_NAMESPACE_MOUNTS");
-
if (mnts==0) return execvWorker(path, argv);
{
- char buf[512 + 2*strlen(mnts)];
- int status;
- pid_t p;
- struct ExecvParams params = {
- .path = path,
- .argv = argv,
- .mnts = mnts,
- };
-
- pid_t pid = clone(removeNamespaceMountsChild, buf+sizeof(buf)/2,
- CLONE_NEWNS|SIGCHLD|CLONE_VFORK, ¶ms);
+ int status;
+ pid_t p, pid;
+ struct ExecvParams params;
+
+ params.path = path;
+ params.argv = argv;
+ params.mnts = mnts;
+
+ // the rpmlib signal-handler is still active; use the default one to
+ // make wait4() working...
+ signal(SIGCHLD, SIG_DFL);
+
+ pid = syscall(__NR_clone, CLONE_NEWNS|SIGCHLD|CLONE_VFORK, 0);
- if (pid==-1) return -1;
- while ((p=waitpid(pid, &status, 0))==-1 &&
+ switch (pid) {
+ case -1 : return -1;
+ case 0 : _exit(removeNamespaceMountsChild(¶ms));
+ default : break;
+ }
+
+ while ((p=wait4(pid, &status, 0,0))==-1 &&
(errno==EINTR || errno==EAGAIN)) ;
+
if (p==-1) return -1;
- if (WIFEXITED(status)) exit(WEXITSTATUS(status));
+ if (WIFEXITED(status)) _exit(WEXITSTATUS(status));
if (WIFSIGNALED(status)) kill(getpid(), WTERMSIG(status));
return -1;
}
}
+
int
execv(char const *path, char * const argv[]) __THROW
{
- initLib();
- fixPreloadEnv();
return removeNamespaceMounts(path, argv);
}