gpg: photoid: Use standard spawn API.

* g10/photoid.c (exec_write, exec_read, exec_finish): Remove.
(setup_input_file): Rename from make_tempdir.
(expand_args): Drop support of 'o' and 'O'.
(fill_command_argv, run_with_pipe, create_temp_file) New.
(show_photo): New with gnupg_spawn_process_fd and gnupg_wait_process.
(show_photos): Call show_photo.

GnuPG-bug-id: 4362
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
This commit is contained in:
NIIBE Yutaka 2019-07-25 11:41:37 +09:00
parent c57c5004ec
commit fd9e6ae22e
1 changed files with 267 additions and 498 deletions

View File

@ -281,8 +281,6 @@ get_default_photo_command(void)
#elif defined(__APPLE__)
/* OS X. This really needs more than just __APPLE__. */
return "open %I";
#elif defined(__riscos__)
return "Filer_Run %I";
#else
if (!path_access ("xloadimage", X_OK))
return "xloadimage -fork -quiet -title 'KeyID 0x%k' stdin";
@ -297,192 +295,144 @@ get_default_photo_command(void)
#endif
#ifndef DISABLE_PHOTO_VIEWER
struct exec_info
struct spawn_info
{
int progreturn;
struct
{
unsigned int binary:1;
unsigned int writeonly:1;
unsigned int madedir:1;
unsigned int use_temp_files:1;
unsigned int keep_temp_files:1;
} flags;
pid_t child;
FILE *tochild;
iobuf_t fromchild;
char *command,*name,*tempdir,*tempfile_in,*tempfile_out;
unsigned int keep_temp_file;
char *command;
char *tempdir;
char *tempfile;
};
#ifdef NO_EXEC
static int
exec_write(struct exec_info **info,const char *program,
const char *args_in,const char *name,int writeonly,int binary)
static void
show_photo (const char *command, const char *name, const void *image, u32 len)
{
log_error(_("no remote program execution supported\n"));
return GPG_ERR_GENERAL;
}
static int
exec_read(struct exec_info *info) { return GPG_ERR_GENERAL; }
static int
exec_finish(struct exec_info *info) { return GPG_ERR_GENERAL; }
#else /* ! NO_EXEC */
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/types.h>
#ifndef EXEC_TEMPFILE_ONLY
#include <sys/wait.h>
#endif
#include <fcntl.h>
#include <errno.h>
#include "../common/membuf.h"
#include "../common/sysutils.h"
#include "../common/exechelp.h"
/* Makes a temp directory and filenames */
static int
make_tempdir(struct exec_info *info)
setup_input_file (struct spawn_info *info, const char *name)
{
char *tmp=opt.temp_dir,*namein=info->name,*nameout;
char *tmp = opt.temp_dir;
int len;
#define TEMPLATE "gpg-XXXXXX"
if(!namein)
namein=info->flags.binary?"tempin" EXTSEP_S "bin":"tempin" EXTSEP_S "txt";
/* Initialize by the length of last part in the path + 1 */
len = strlen (DIRSEP_S) + strlen (TEMPLATE) + 1;
nameout=info->flags.binary?"tempout" EXTSEP_S "bin":"tempout" EXTSEP_S "txt";
/* Make up the temp dir and files in case we need them */
if(tmp==NULL)
/* Make up the temp dir and file in case we need them */
if (tmp)
{
#if defined (_WIN32)
int err;
tmp=xmalloc(MAX_PATH+2);
err=GetTempPath(MAX_PATH+1,tmp);
if(err==0 || err>MAX_PATH+1)
strcpy(tmp,"c:\\windows\\temp");
else
{
int len=strlen(tmp);
/* GetTempPath may return with \ on the end */
while(len>0 && tmp[len-1]=='\\')
{
tmp[len-1]='\0';
len--;
}
}
#else /* More unixish systems */
tmp=getenv("TMPDIR");
if(tmp==NULL)
{
tmp=getenv("TMP");
if(tmp==NULL)
{
#ifdef __riscos__
tmp="<Wimp$ScrapDir>.GnuPG";
mkdir(tmp,0700); /* Error checks occur later on */
#else
tmp="/tmp";
#endif
}
}
#endif
len += strlen (tmp);
info->tempdir = xmalloc (len);
}
info->tempdir=xmalloc(strlen(tmp)+strlen(DIRSEP_S)+10+1);
sprintf(info->tempdir,"%s" DIRSEP_S "gpg-XXXXXX",tmp);
#if defined (_WIN32)
xfree(tmp);
#endif
if (!gnupg_mkdtemp(info->tempdir))
log_error(_("can't create directory '%s': %s\n"),
info->tempdir,strerror(errno));
else
{
info->flags.madedir=1;
#if defined (_WIN32)
int ret;
info->tempfile_in=xmalloc(strlen(info->tempdir)+
strlen(DIRSEP_S)+strlen(namein)+1);
sprintf(info->tempfile_in,"%s" DIRSEP_S "%s",info->tempdir,namein);
tmp = xmalloc (MAX_PATH+1);
if (!tmp)
return -1;
if(!info->flags.writeonly)
ret = GetTempPath (MAX_PATH-len, tmp);
if (ret == 0 || ret >= MAX_PATH-len)
strcpy (tmp, "c:\\windows\\temp");
else
{
info->tempfile_out=xmalloc(strlen(info->tempdir)+
strlen(DIRSEP_S)+strlen(nameout)+1);
sprintf(info->tempfile_out,"%s" DIRSEP_S "%s",info->tempdir,nameout);
/* GetTempPath may return with \ on the end */
while (ret > 0 && tmp[ret-1] == '\\')
{
tmp[ret-1]='\0';
ret--;
}
}
len += ret;
info->tempdir = tmp;
#else /* More unixish systems */
if (!(tmp = getenv ("TMPDIR"))
&& !(tmp = getenv ("TMP")))
tmp = "/tmp";
len += strlen (tmp);
info->tempdir = xmalloc (len);
#endif
}
return info->flags.madedir? 0 : GPG_ERR_GENERAL;
if (info->tempdir == NULL)
return -1;
sprintf (info->tempdir, "%s" DIRSEP_S TEMPLATE, tmp);
if (gnupg_mkdtemp (info->tempdir) == NULL)
{
log_error (_("can't create directory '%s': %s\n"),
info->tempdir, strerror (errno));
return -1;
}
info->tempfile = xmalloc (strlen (info->tempdir) + strlen (DIRSEP_S)
+ strlen (name) + 1);
if (info->tempfile == NULL)
{
xfree (info->tempdir);
info->tempdir = NULL;
return -1;
}
sprintf (info->tempfile, "%s" DIRSEP_S "%s", info->tempdir, name);
return 0;
}
/* Expands %i and %o in the args to the full temp files within the
temp directory. */
/* Expands %i or %I in the args to the full temp file within the temp
directory. */
static int
expand_args(struct exec_info *info,const char *args_in)
expand_args (struct spawn_info *info, const char *args_in, const char *name)
{
const char *ch = args_in;
membuf_t command;
info->flags.use_temp_files=0;
info->flags.keep_temp_files=0;
info->keep_temp_file = 0;
if(DBG_EXTPROG)
log_debug("expanding string \"%s\"\n",args_in);
if (DBG_EXTPROG)
log_debug ("expanding string \"%s\"\n", args_in);
init_membuf (&command, 100);
while(*ch!='\0')
while (*ch != '\0')
{
if(*ch=='%')
if (*ch == '%')
{
char *append=NULL;
const char *append = NULL;
ch++;
switch(*ch)
switch (*ch)
{
case 'O':
info->flags.keep_temp_files=1;
/* fall through */
case 'o': /* out */
if(!info->flags.madedir)
{
if(make_tempdir(info))
goto fail;
}
append=info->tempfile_out;
info->flags.use_temp_files=1;
break;
case 'I':
info->flags.keep_temp_files=1;
info->keep_temp_file = 1;
/* fall through */
case 'i': /* in */
if(!info->flags.madedir)
if (info->tempfile == NULL)
{
if(make_tempdir(info))
if (setup_input_file (info, name) < 0)
goto fail;
}
append=info->tempfile_in;
info->flags.use_temp_files=1;
append = info->tempfile;
break;
case '%':
append="%";
append = "%";
break;
}
if(append)
if (append)
put_membuf_str (&command, append);
}
else
@ -495,348 +445,167 @@ expand_args(struct exec_info *info,const char *args_in)
info->command = get_membuf (&command, NULL);
if (!info->command)
return gpg_error_from_syserror ();
return -1;
if(DBG_EXTPROG)
log_debug("args expanded to \"%s\", use %u, keep %u\n",info->command,
info->flags.use_temp_files,info->flags.keep_temp_files);
log_debug("args expanded to \"%s\", use %s, keep %u\n", info->command,
info->tempfile, info->keep_temp_file);
return 0;
fail:
xfree (get_membuf (&command, NULL));
return GPG_ERR_GENERAL;
return -1;
}
/* Either handles the tempfile creation, or the fork/exec. If it
returns ok, then info->tochild is a FILE * that can be written to.
The rules are: if there are no args, then it's a fork/exec/pipe.
If there are args, but no tempfiles, then it's a fork/exec/pipe via
shell -c. If there are tempfiles, then it's a system. */
static int
exec_write(struct exec_info **info,const char *program,
const char *args_in,const char *name,int writeonly,int binary)
{
int ret = GPG_ERR_GENERAL;
if(opt.exec_disable && !opt.no_perm_warn)
{
log_info(_("external program calls are disabled due to unsafe "
"options file permissions\n"));
return ret;
}
#if defined(HAVE_GETUID) && defined(HAVE_GETEUID)
/* There should be no way to get to this spot while still carrying
setuid privs. Just in case, bomb out if we are. */
if ( getuid () != geteuid ())
BUG ();
#endif
if(program==NULL && args_in==NULL)
BUG();
*info=xmalloc_clear(sizeof(struct exec_info));
if(name)
(*info)->name=xstrdup(name);
(*info)->flags.binary=binary;
(*info)->flags.writeonly=writeonly;
/* Expand the args, if any */
if(args_in && expand_args(*info,args_in))
goto fail;
#ifdef EXEC_TEMPFILE_ONLY
if(!(*info)->flags.use_temp_files)
{
log_error(_("this platform requires temporary files when calling"
" external programs\n"));
goto fail;
}
#else /* !EXEC_TEMPFILE_ONLY */
/* If there are no args, or there are args, but no temp files, we
can use fork/exec/pipe */
if(args_in==NULL || (*info)->flags.use_temp_files==0)
{
int to[2],from[2];
if(pipe(to)==-1)
goto fail;
if(pipe(from)==-1)
{
close(to[0]);
close(to[1]);
goto fail;
}
if(((*info)->child=fork())==-1)
{
close(to[0]);
close(to[1]);
close(from[0]);
close(from[1]);
goto fail;
}
if((*info)->child==0)
{
char *shell=getenv("SHELL");
if(shell==NULL)
shell="/bin/sh";
/* I'm the child */
/* If the program isn't going to respond back, they get to
keep their stdout/stderr */
if(!(*info)->flags.writeonly)
{
/* implied close of STDERR */
if(dup2(STDOUT_FILENO,STDERR_FILENO)==-1)
_exit(1);
/* implied close of STDOUT */
close(from[0]);
if(dup2(from[1],STDOUT_FILENO)==-1)
_exit(1);
}
/* implied close of STDIN */
close(to[1]);
if(dup2(to[0],STDIN_FILENO)==-1)
_exit(1);
if(args_in==NULL)
{
if(DBG_EXTPROG)
log_debug("execlp: %s\n",program);
execlp(program,program,(void *)NULL);
}
else
{
if(DBG_EXTPROG)
log_debug("execlp: %s -c %s\n",shell,(*info)->command);
execlp(shell,shell,"-c",(*info)->command,(void *)NULL);
}
/* If we get this far the exec failed. Clean up and return. */
if(args_in==NULL)
log_error(_("unable to execute program '%s': %s\n"),
program,strerror(errno));
else
log_error(_("unable to execute shell '%s': %s\n"),
shell,strerror(errno));
/* This mimics the POSIX sh behavior - 127 means "not found"
from the shell. */
if(errno==ENOENT)
_exit(127);
_exit(1);
}
/* I'm the parent */
close(to[0]);
(*info)->tochild=fdopen(to[1],binary?"wb":"w");
if((*info)->tochild==NULL)
{
ret = gpg_error_from_syserror ();
close(to[1]);
goto fail;
}
close(from[1]);
(*info)->fromchild=iobuf_fdopen(from[0],"r");
if((*info)->fromchild==NULL)
{
ret = gpg_error_from_syserror ();
close(from[0]);
goto fail;
}
/* fd iobufs are cached! */
iobuf_ioctl((*info)->fromchild, IOBUF_IOCTL_NO_CACHE, 1, NULL);
return 0;
}
#endif /* !EXEC_TEMPFILE_ONLY */
if(DBG_EXTPROG)
log_debug("using temp file '%s'\n",(*info)->tempfile_in);
/* It's not fork/exec/pipe, so create a temp file */
if( is_secured_filename ((*info)->tempfile_in) )
{
(*info)->tochild = NULL;
gpg_err_set_errno (EPERM);
}
else
(*info)->tochild=fopen((*info)->tempfile_in,binary?"wb":"w");
if((*info)->tochild==NULL)
{
ret = gpg_error_from_syserror ();
log_error(_("can't create '%s': %s\n"),
(*info)->tempfile_in,strerror(errno));
goto fail;
}
ret=0;
fail:
if (ret)
{
xfree (*info);
*info = NULL;
}
return ret;
}
static int
exec_read(struct exec_info *info)
{
int ret = GPG_ERR_GENERAL;
fclose(info->tochild);
info->tochild=NULL;
if(info->flags.use_temp_files)
{
if(DBG_EXTPROG)
log_debug ("running command: %s\n",info->command);
#if defined (_WIN32)
info->progreturn=w32_system(info->command);
#else
info->progreturn=system(info->command);
#endif
if(info->progreturn==-1)
{
log_error(_("system error while calling external program: %s\n"),
strerror(errno));
info->progreturn=127;
goto fail;
}
#if defined(WIFEXITED) && defined(WEXITSTATUS)
if(WIFEXITED(info->progreturn))
info->progreturn=WEXITSTATUS(info->progreturn);
else
{
log_error(_("unnatural exit of external program\n"));
info->progreturn=127;
goto fail;
}
#else
/* If we don't have the macros, do the best we can. */
info->progreturn = (info->progreturn & 0xff00) >> 8;
#endif
/* 127 is the magic value returned from system() to indicate
that the shell could not be executed, or from /bin/sh to
indicate that the program could not be executed. */
if(info->progreturn==127)
{
log_error(_("unable to execute external program\n"));
goto fail;
}
if(!info->flags.writeonly)
{
info->fromchild=iobuf_open(info->tempfile_out);
if (info->fromchild
&& is_secured_file (iobuf_get_fd (info->fromchild)))
{
iobuf_close (info->fromchild);
info->fromchild = NULL;
gpg_err_set_errno (EPERM);
}
if(info->fromchild==NULL)
{
ret = gpg_error_from_syserror ();
log_error(_("unable to read external program response: %s\n"),
strerror(errno));
goto fail;
}
/* Do not cache this iobuf on close */
iobuf_ioctl(info->fromchild, IOBUF_IOCTL_NO_CACHE, 1, NULL);
}
}
ret=0;
fail:
return ret;
}
static int
exec_finish(struct exec_info *info)
{
int ret=info->progreturn;
if(info->fromchild)
iobuf_close(info->fromchild);
if(info->tochild)
fclose(info->tochild);
#ifndef EXEC_TEMPFILE_ONLY
if(info->child>0)
{
if(waitpid(info->child,&info->progreturn,0)!=0 &&
WIFEXITED(info->progreturn))
ret=WEXITSTATUS(info->progreturn);
else
{
log_error(_("unnatural exit of external program\n"));
ret=127;
}
}
static void
fill_command_argv (const char *argv[4], const char *command)
{
argv[0] = getenv ("SHELL");
if (argv[0] == NULL)
argv[0] = "/bin/sh";
argv[1] = "-c";
argv[2] = command;
argv[3] = NULL;
}
#endif
if(info->flags.madedir && !info->flags.keep_temp_files)
static void
run_with_pipe (struct spawn_info *info, const void *image, u32 len)
{
#ifdef EXEC_TEMPFILE_ONLY
(void)info;
(void)image;
(void)len;
log_error (_("this platform requires temporary files when calling"
" external programs\n"));
return;
#else /* !EXEC_TEMPFILE_ONLY */
int to[2];
pid_t pid;
gpg_error_t err;
const char *argv[4];
err = gnupg_create_pipe (to);
if (err)
return;
fill_command_argv (argv, info->command);
err = gnupg_spawn_process_fd (argv[0], argv+1, to[0], -1, -1, &pid);
close (to[0]);
if (err)
{
if(info->tempfile_in)
{
if(unlink(info->tempfile_in)==-1)
log_info(_("WARNING: unable to remove tempfile (%s) '%s': %s\n"),
"in",info->tempfile_in,strerror(errno));
}
log_error (_("unable to execute shell '%s': %s\n"),
argv[0], gpg_strerror (err));
close (to[1]);
}
else
{
write (to[1], image, len);
close (to[1]);
if(info->tempfile_out)
{
if(unlink(info->tempfile_out)==-1)
log_info(_("WARNING: unable to remove tempfile (%s) '%s': %s\n"),
"out",info->tempfile_out,strerror(errno));
}
err = gnupg_wait_process (argv[0], pid, 1, NULL);
if (err)
log_error (_("unnatural exit of external program\n"));
}
#endif /* !EXEC_TEMPFILE_ONLY */
}
if(rmdir(info->tempdir)==-1)
log_info(_("WARNING: unable to remove temp directory '%s': %s\n"),
info->tempdir,strerror(errno));
static int
create_temp_file (struct spawn_info *info, const void *ptr, u32 len)
{
if (DBG_EXTPROG)
log_debug ("using temp file '%s'\n", info->tempfile);
/* It's not fork/exec/pipe, so create a temp file */
if ( is_secured_filename (info->tempfile) )
{
log_error (_("can't create '%s': %s\n"),
info->tempfile, strerror (EPERM));
gpg_err_set_errno (EPERM);
return -1;
}
else
{
FILE *fp = fopen (info->tempfile, "wb");
if (fp)
{
fwrite (ptr, len, 1, fp);
fclose (fp);
return 0;
}
else
{
int save = errno;
log_error (_("can't create '%s': %s\n"),
info->tempfile, strerror(errno));
gpg_err_set_errno (save);
return -1;
}
}
}
static void
show_photo (const char *command, const char *name, const void *image, u32 len)
{
struct spawn_info *spawn;
spawn = xmalloc_clear (sizeof (struct spawn_info));
if (!spawn)
return;
/* Expand the args */
if (expand_args (spawn, command, name) < 0)
{
xfree (spawn);
return;
}
xfree(info->command);
xfree(info->name);
xfree(info->tempdir);
xfree(info->tempfile_in);
xfree(info->tempfile_out);
xfree(info);
if (DBG_EXTPROG)
log_debug ("running command: %s\n", spawn->command);
return ret;
if (spawn->tempfile == NULL)
run_with_pipe (spawn, image, len);
else if (create_temp_file (spawn, image, len) == 0)
{
#if defined (_WIN32)
if (w32_system (spawn->command) < 0)
log_error (_("system error while calling external program: %s\n"),
strerror (errno));
#else
pid_t pid;
gpg_error_t err;
const char *argv[4];
fill_command_argv (argv, spawn->command);
err = gnupg_spawn_process_fd (argv[0], argv+1, -1, -1, -1, &pid);
if (!err)
err = gnupg_wait_process (argv[0], pid, 1, NULL);
if (err)
log_error (_("unnatural exit of external program\n"));
#endif
if (!spawn->keep_temp_file)
{
if (unlink (spawn->tempfile) < 0)
log_info (_("WARNING: unable to remove tempfile (%s) '%s': %s\n"),
"in", spawn->tempfile, strerror(errno));
if (rmdir (spawn->tempdir) < 0)
log_info (_("WARNING: unable to remove temp directory '%s': %s\n"),
spawn->tempdir, strerror(errno));
}
}
xfree(spawn->command);
xfree(spawn->tempdir);
xfree(spawn->tempfile);
xfree(spawn);
}
#endif
#endif
@ -857,6 +626,20 @@ show_photos (ctrl_t ctrl, const struct user_attribute *attrs, int count,
u32 len;
u32 kid[2]={0,0};
if (opt.exec_disable && !opt.no_perm_warn)
{
log_info (_("external program calls are disabled due to unsafe "
"options file permissions\n"));
return;
}
#if defined(HAVE_GETUID) && defined(HAVE_GETEUID)
/* There should be no way to get to this spot while still carrying
setuid privs. Just in case, bomb out if we are. */
if ( getuid () != geteuid ())
BUG ();
#endif
memset (&args, 0, sizeof(args));
args.pk = pk;
args.validity_info = get_validity_info (ctrl, NULL, pk, uid);
@ -869,28 +652,33 @@ show_photos (ctrl_t ctrl, const struct user_attribute *attrs, int count,
es_fflush (es_stdout);
for(i=0;i<count;i++)
if(attrs[i].type==ATTRIB_IMAGE &&
parse_image_header(&attrs[i],&args.imagetype,&len))
{
char *command,*name;
struct exec_info *spawn;
int offset=attrs[i].len-len;
#ifdef FIXED_PHOTO_VIEWER
opt.photo_viewer=FIXED_PHOTO_VIEWER;
opt.photo_viewer = FIXED_PHOTO_VIEWER;
#else
if(!opt.photo_viewer)
opt.photo_viewer=get_default_photo_command();
if (!opt.photo_viewer)
opt.photo_viewer = get_default_photo_command ();
#endif
for (i=0; i<count; i++)
if (attrs[i].type == ATTRIB_IMAGE
&& parse_image_header (&attrs[i], &args.imagetype, &len))
{
char *command, *name;
int offset = attrs[i].len-len;
/* make command grow */
command=pct_expando(opt.photo_viewer,&args);
if(!command)
command = pct_expando (opt.photo_viewer, &args);
if (!command)
goto fail;
name=xmalloc(16+strlen(EXTSEP_S)+
strlen(image_type_to_string(args.imagetype,0))+1);
name = xmalloc (1 + 16 + strlen(EXTSEP_S)
+ strlen (image_type_to_string (args.imagetype, 0)));
if (!name)
{
xfree (command);
goto fail;
}
/* Make the filename. Notice we are not using the image
encoding type for more than cosmetics. Most external image
@ -899,36 +687,17 @@ show_photos (ctrl_t ctrl, const struct user_attribute *attrs, int count,
which. The spec permits this, by the way. -dms */
#ifdef USE_ONLY_8DOT3
sprintf(name,"%08lX" EXTSEP_S "%s",(ulong)kid[1],
image_type_to_string(args.imagetype,0));
sprintf (name,"%08lX" EXTSEP_S "%s", (ulong)kid[1],
image_type_to_string (args.imagetype, 0));
#else
sprintf(name,"%08lX%08lX" EXTSEP_S "%s",(ulong)kid[0],(ulong)kid[1],
image_type_to_string(args.imagetype,0));
sprintf (name, "%08lX%08lX" EXTSEP_S "%s",
(ulong)kid[0], (ulong)kid[1],
image_type_to_string (args.imagetype, 0));
#endif
if(exec_write(&spawn,NULL,command,name,1,1)!=0)
{
xfree(name);
goto fail;
}
#ifdef __riscos__
riscos_set_filetype_by_mimetype(spawn->tempfile_in,
image_type_to_string(args.imagetype,2));
#endif
xfree(name);
fwrite(&attrs[i].data[offset],attrs[i].len-offset,1,spawn->tochild);
if(exec_read(spawn)!=0)
{
exec_finish(spawn);
goto fail;
}
if(exec_finish(spawn)!=0)
goto fail;
show_photo (command, name, &attrs[i].data[offset], len);
xfree (name);
xfree (command);
}
return;