summaryrefslogtreecommitdiffstats
path: root/g10/exec.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--g10/exec.c705
1 files changed, 705 insertions, 0 deletions
diff --git a/g10/exec.c b/g10/exec.c
new file mode 100644
index 0000000..bf0d8f2
--- /dev/null
+++ b/g10/exec.c
@@ -0,0 +1,705 @@
+/* exec.c - generic call-a-program code
+ * Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ */
+
+/*
+ FIXME: We should replace most code in this module by our
+ spawn implementation from common/exechelp.c.
+ */
+
+
+#include <config.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#ifndef EXEC_TEMPFILE_ONLY
+#include <sys/wait.h>
+#endif
+#ifdef HAVE_DOSISH_SYSTEM
+# ifdef HAVE_WINSOCK2_H
+# include <winsock2.h>
+# endif
+# include <windows.h>
+#endif
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+
+#include "gpg.h"
+#include "options.h"
+#include "../common/i18n.h"
+#include "../common/iobuf.h"
+#include "../common/util.h"
+#include "../common/membuf.h"
+#include "../common/sysutils.h"
+#include "exec.h"
+
+#ifdef NO_EXEC
+int
+exec_write(struct exec_info **info,const char *program,
+ const char *args_in,const char *name,int writeonly,int binary)
+{
+ log_error(_("no remote program execution supported\n"));
+ return GPG_ERR_GENERAL;
+}
+
+int
+exec_read(struct exec_info *info) { return GPG_ERR_GENERAL; }
+int
+exec_finish(struct exec_info *info) { return GPG_ERR_GENERAL; }
+int
+set_exec_path(const char *path) { return GPG_ERR_GENERAL; }
+
+#else /* ! NO_EXEC */
+
+#if defined (_WIN32)
+/* This is a nicer system() for windows that waits for programs to
+ return before returning control to the caller. I hate helpful
+ computers. */
+static int
+w32_system(const char *command)
+{
+ if (!strncmp (command, "!ShellExecute ", 14))
+ {
+ SHELLEXECUTEINFOW see;
+ wchar_t *wname;
+ int waitms;
+
+ command = command + 14;
+ while (spacep (command))
+ command++;
+ waitms = atoi (command);
+ if (waitms < 0)
+ waitms = 0;
+ else if (waitms > 60*1000)
+ waitms = 60000;
+ while (*command && !spacep (command))
+ command++;
+ while (spacep (command))
+ command++;
+
+ wname = utf8_to_wchar (command);
+ if (!wname)
+ return -1;
+
+ memset (&see, 0, sizeof see);
+ see.cbSize = sizeof see;
+ see.fMask = (SEE_MASK_NOCLOSEPROCESS
+ | SEE_MASK_NOASYNC
+ | SEE_MASK_FLAG_NO_UI
+ | SEE_MASK_NO_CONSOLE);
+ see.lpVerb = L"open";
+ see.lpFile = (LPCWSTR)wname;
+ see.nShow = SW_SHOW;
+
+ if (DBG_EXTPROG)
+ log_debug ("running ShellExecuteEx(open,'%s')\n", command);
+ if (!ShellExecuteExW (&see))
+ {
+ if (DBG_EXTPROG)
+ log_debug ("ShellExecuteEx failed: rc=%d\n", (int)GetLastError ());
+ xfree (wname);
+ return -1;
+ }
+ if (DBG_EXTPROG)
+ log_debug ("ShellExecuteEx succeeded (hProcess=%p,hInstApp=%d)\n",
+ see.hProcess, (int)see.hInstApp);
+
+ if (!see.hProcess)
+ {
+ gnupg_usleep (waitms*1000);
+ if (DBG_EXTPROG)
+ log_debug ("ShellExecuteEx ready (wait=%dms)\n", waitms);
+ }
+ else
+ {
+ WaitForSingleObject (see.hProcess, INFINITE);
+ if (DBG_EXTPROG)
+ log_debug ("ShellExecuteEx ready\n");
+ }
+ CloseHandle (see.hProcess);
+
+ xfree (wname);
+ }
+ else
+ {
+ char *string;
+ wchar_t *wstring;
+ PROCESS_INFORMATION pi;
+ STARTUPINFOW si;
+
+ /* We must use a copy of the command as CreateProcess modifies
+ * this argument. */
+ string = xstrdup (command);
+ wstring = utf8_to_wchar (string);
+ xfree (string);
+ if (!wstring)
+ return -1;
+
+ memset (&pi, 0, sizeof(pi));
+ memset (&si, 0, sizeof(si));
+ si.cb = sizeof (si);
+
+ if (!CreateProcessW (NULL, wstring, NULL, NULL, FALSE,
+ DETACHED_PROCESS,
+ NULL, NULL, &si, &pi))
+ {
+ xfree (wstring);
+ return -1;
+ }
+
+ /* Wait for the child to exit */
+ WaitForSingleObject (pi.hProcess, INFINITE);
+
+ CloseHandle (pi.hProcess);
+ CloseHandle (pi.hThread);
+ xfree (wstring);
+ }
+
+ return 0;
+}
+#endif /*_W32*/
+
+
+/* Replaces current $PATH */
+int
+set_exec_path(const char *path)
+{
+#ifdef HAVE_W32CE_SYSTEM
+#warning Change this code to use common/exechelp.c
+#else
+ char *p;
+
+ p=xmalloc(5+strlen(path)+1);
+ strcpy(p,"PATH=");
+ strcat(p,path);
+
+ if(DBG_EXTPROG)
+ log_debug("set_exec_path: %s\n",p);
+
+ /* Notice that path is never freed. That is intentional due to the
+ way putenv() works. This leaks a few bytes if we call
+ set_exec_path multiple times. */
+
+ if(putenv(p)!=0)
+ return GPG_ERR_GENERAL;
+ else
+ return 0;
+#endif
+}
+
+/* Makes a temp directory and filenames */
+static int
+make_tempdir(struct exec_info *info)
+{
+ char *tmp=opt.temp_dir,*namein=info->name,*nameout;
+
+ if(!namein)
+ namein=info->flags.binary?"tempin" EXTSEP_S "bin":"tempin" EXTSEP_S "txt";
+
+ nameout=info->flags.binary?"tempout" EXTSEP_S "bin":"tempout" EXTSEP_S "txt";
+
+ /* Make up the temp dir and files in case we need them */
+
+ if(tmp==NULL)
+ {
+#if defined (_WIN32)
+ int err;
+
+ tmp=xmalloc(MAX_PATH+2);
+ err=GetTempPath(MAX_PATH+1,tmp);
+ if(err==0 || err>MAX_PATH+1)
+ strcpy(tmp,"c:\\windows\\temp");
+ else
+ {
+ int len=strlen(tmp);
+
+ /* GetTempPath may return with \ on the end */
+ while(len>0 && tmp[len-1]=='\\')
+ {
+ tmp[len-1]='\0';
+ len--;
+ }
+ }
+#else /* More unixish systems */
+ tmp=getenv("TMPDIR");
+ if(tmp==NULL)
+ {
+ tmp=getenv("TMP");
+ if(tmp==NULL)
+ {
+#ifdef __riscos__
+ tmp="<Wimp$ScrapDir>.GnuPG";
+ mkdir(tmp,0700); /* Error checks occur later on */
+#else
+ tmp="/tmp";
+#endif
+ }
+ }
+#endif
+ }
+
+ 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;
+
+ info->tempfile_in=xmalloc(strlen(info->tempdir)+
+ strlen(DIRSEP_S)+strlen(namein)+1);
+ sprintf(info->tempfile_in,"%s" DIRSEP_S "%s",info->tempdir,namein);
+
+ if(!info->flags.writeonly)
+ {
+ info->tempfile_out=xmalloc(strlen(info->tempdir)+
+ strlen(DIRSEP_S)+strlen(nameout)+1);
+ sprintf(info->tempfile_out,"%s" DIRSEP_S "%s",info->tempdir,nameout);
+ }
+ }
+
+ return info->flags.madedir? 0 : GPG_ERR_GENERAL;
+}
+
+/* Expands %i and %o in the args to the full temp files within the
+ temp directory. */
+static int
+expand_args(struct exec_info *info,const char *args_in)
+{
+ const char *ch = args_in;
+ membuf_t command;
+
+ info->flags.use_temp_files=0;
+ info->flags.keep_temp_files=0;
+
+ if(DBG_EXTPROG)
+ log_debug("expanding string \"%s\"\n",args_in);
+
+ init_membuf (&command, 100);
+
+ while(*ch!='\0')
+ {
+ if(*ch=='%')
+ {
+ char *append=NULL;
+
+ 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;
+ /* fall through */
+
+ case 'i': /* in */
+ if(!info->flags.madedir)
+ {
+ if(make_tempdir(info))
+ goto fail;
+ }
+ append=info->tempfile_in;
+ info->flags.use_temp_files=1;
+ break;
+
+ case '%':
+ append="%";
+ break;
+ }
+
+ if(append)
+ put_membuf_str (&command, append);
+ }
+ else
+ put_membuf (&command, ch, 1);
+
+ ch++;
+ }
+
+ put_membuf (&command, "", 1); /* Terminate string. */
+
+ info->command = get_membuf (&command, NULL);
+ if (!info->command)
+ return gpg_error_from_syserror ();
+
+ 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);
+
+ return 0;
+
+ fail:
+ xfree (get_membuf (&command, NULL));
+ return GPG_ERR_GENERAL;
+}
+
+/* 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. */
+
+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 = gnupg_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;
+}
+
+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;
+}
+
+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;
+ }
+ }
+#endif
+
+ if(info->flags.madedir && !info->flags.keep_temp_files)
+ {
+ 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));
+ }
+
+ 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));
+ }
+
+ if(rmdir(info->tempdir)==-1)
+ log_info(_("WARNING: unable to remove temp directory '%s': %s\n"),
+ info->tempdir,strerror(errno));
+ }
+
+ xfree(info->command);
+ xfree(info->name);
+ xfree(info->tempdir);
+ xfree(info->tempfile_in);
+ xfree(info->tempfile_out);
+ xfree(info);
+
+ return ret;
+}
+#endif /* ! NO_EXEC */
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-25 23:24:23 +0000