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/**
* \file lib/fileutil.c
*/
#include "system.h"
#include <rpmlib.h>
#include "misc.h"
#include "debug.h"
static struct {
const char *token;
int nargs;
} cmds[] = {
{ "mkdir", 1 },
#define RPMSYSCALL_MKDIR 0
{ "rmdir", 1 },
#define RPMSYSCALL_RMDIR 1
{ "mv", -2 },
#define RPMSYSCALL_MV 2
{ "symlink", 2 },
#define RPMSYSCALL_SYMLINK 3
{ "S_ISLNK", 1 }
#define RPMSYSCALL_ISLNK 4
};
int ncmds = sizeof(cmds)/sizeof(cmds[0]);
int rpmSyscall(const char * cmd, int noexec)
{
const char ** argv = NULL;
int argc;
struct stat st;
int i, j;
int rc;
rc = (noexec)
? poptParseArgvString(cmd, &argc, &argv)
: rpmGlob(cmd, &argc, &argv);
if (rc)
goto exit;
/* Check: argv[0] must be known. */
for (i = 0; i < ncmds; i++) {
if (!strcmp(cmds[i].token, argv[0]))
break;
}
if (i >= ncmds) {
rc = EPERM;
goto exit;
}
/* Check: must have exactly (or, if negative, at least) nargs. */
if (cmds[i].nargs >= 0 && argc != (cmds[i].nargs+1)) {
rc = EPERM;
goto exit;
} else if (argc < (1-cmds[i].nargs)) {
rc = EPERM;
goto exit;
}
/* Check: all args (except for 1st arg to symlink) must start with '/'. */
for (j = (i == RPMSYSCALL_SYMLINK ? 2 : 1); j < argc; j++) {
if (argv[j][0] != '/') {
rc = EPERM;
goto exit;
}
}
/* Check: parse only with 2 or more args, last arg cannot be glob. */
if (noexec) {
if (argc > 2 && myGlobPatternP(argv[argc-1])) {
rc = 1;
goto exit;
}
rc = 0;
goto exit;
}
/* Execute only checks below */
switch (i) {
case RPMSYSCALL_MKDIR: /* mkdir */
{ mode_t mode = 0755;
rc = mkdir(argv[1], mode);
if (rc < 0) rc = errno;
if (stat(argv[1], &st) < 0) {
if (rc == 0) rc = errno;
goto exit;
}
if (!S_ISDIR(st.st_mode)) {
if (rc == 0) rc = ENOTDIR;
goto exit;
}
rc = 0;
} break;
case RPMSYSCALL_RMDIR: /* rmdir */
rc = rmdir(argv[1]);
if (rc < 0) rc = errno;
break;
case RPMSYSCALL_MV: /* mv */
{ dev_t dev;
const char * fn, * bn;
char * t;
size_t bnlen;
/* Check: if more than 2 args ... */
if (argc > 3) {
/* ... last arg must be existing directory ... */
if (stat(argv[argc-1], &st) < 0) {
if (rc == 0) rc = errno;
goto exit;
}
if (!S_ISDIR(st.st_mode)) {
if (rc == 0) rc = ENOTDIR;
goto exit;
}
/* ... and other args must all be on the same device. */
dev = st.st_dev;
bnlen = 0;
for (j = 1; j < (argc-1); j++) {
if (stat(argv[j], &st) < 0) {
if (rc == 0) rc = errno;
goto exit;
}
if (dev != st.st_dev) {
if (rc == 0) rc = EXDEV;
goto exit;
}
bn = strrchr(argv[j], '/');
if (bn) {
int k = strlen(bn);
if (k > bnlen) bnlen = k;
}
}
/* Everything looks OK, so do the renames. */
fn = t = alloca(strlen(argv[argc-1])+2+bnlen);
t = stpcpy(t, argv[argc-1]);
if (t[-1] != '/') *t++ = '/';
for (j = 1; j < (argc-1); j++) {
bn = strrchr(argv[j], '/');
(void) stpcpy(t, bn+1);
rc = rename(argv[j], fn);
if (rc < 0) {
rc = errno;
goto exit;
}
}
} else { /* Otherwise exactly 2 args. */
rc = rename(argv[1], argv[2]);
if (rc < 0) rc = errno;
}
} break;
case RPMSYSCALL_SYMLINK: /* symlink */
rc = symlink(argv[1], argv[2]);
if (rc < 0) rc = errno;
break;
case RPMSYSCALL_ISLNK: /* stat(2) with S_ISLNK */
if (stat(argv[1], &st) < 0) {
if (rc == 0) rc = errno;
goto exit;
}
if (S_ISLNK(st.st_mode)) {
if (rc == 0) rc = EPERM;
goto exit;
}
rc = 0;
break;
default:
rc = EPERM;
break;
}
exit:
argv = _free(argv);
return rc;
}
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