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-rw-r--r--contrib/sendmail/libsmutil/safefile.c955
1 files changed, 0 insertions, 955 deletions
diff --git a/contrib/sendmail/libsmutil/safefile.c b/contrib/sendmail/libsmutil/safefile.c
deleted file mode 100644
index aed40a0482e0..000000000000
--- a/contrib/sendmail/libsmutil/safefile.c
+++ /dev/null
@@ -1,955 +0,0 @@
-/*
- * Copyright (c) 1998-2002 Sendmail, Inc. and its suppliers.
- * All rights reserved.
- * Copyright (c) 1983, 1995-1997 Eric P. Allman. All rights reserved.
- * Copyright (c) 1988, 1993
- * The Regents of the University of California. All rights reserved.
- *
- * By using this file, you agree to the terms and conditions set
- * forth in the LICENSE file which can be found at the top level of
- * the sendmail distribution.
- *
- */
-
-#include <sendmail.h>
-#include <sm/io.h>
-#include <sm/errstring.h>
-
-SM_RCSID("@(#)$Id: safefile.c,v 8.124 2002/05/24 20:50:15 gshapiro Exp $")
-
-
-/*
-** SAFEFILE -- return 0 if a file exists and is safe for a user.
-**
-** Parameters:
-** fn -- filename to check.
-** uid -- user id to compare against.
-** gid -- group id to compare against.
-** user -- user name to compare against (used for group
-** sets).
-** flags -- modifiers:
-** SFF_MUSTOWN -- "uid" must own this file.
-** SFF_NOSLINK -- file cannot be a symbolic link.
-** mode -- mode bits that must match.
-** st -- if set, points to a stat structure that will
-** get the stat info for the file.
-**
-** Returns:
-** 0 if fn exists, is owned by uid, and matches mode.
-** An errno otherwise. The actual errno is cleared.
-**
-** Side Effects:
-** none.
-*/
-
-int
-safefile(fn, uid, gid, user, flags, mode, st)
- char *fn;
- UID_T uid;
- GID_T gid;
- char *user;
- long flags;
- int mode;
- struct stat *st;
-{
- register char *p;
- register struct group *gr = NULL;
- int file_errno = 0;
- bool checkpath;
- struct stat stbuf;
- struct stat fstbuf;
- char fbuf[MAXPATHLEN];
-
- if (tTd(44, 4))
- sm_dprintf("safefile(%s, uid=%d, gid=%d, flags=%lx, mode=%o):\n",
- fn, (int) uid, (int) gid, flags, mode);
- errno = 0;
- if (sm_strlcpy(fbuf, fn, sizeof fbuf) >= sizeof fbuf)
- {
- if (tTd(44, 4))
- sm_dprintf("\tpathname too long\n");
- return ENAMETOOLONG;
- }
- fn = fbuf;
- if (st == NULL)
- st = &fstbuf;
-
- /* ignore SFF_SAFEDIRPATH if we are debugging */
- if (RealUid != 0 && RunAsUid == RealUid)
- flags &= ~SFF_SAFEDIRPATH;
-
- /* first check to see if the file exists at all */
-# if HASLSTAT
- if ((bitset(SFF_NOSLINK, flags) ? lstat(fn, st)
- : stat(fn, st)) < 0)
-# else /* HASLSTAT */
- if (stat(fn, st) < 0)
-# endif /* HASLSTAT */
- {
- file_errno = errno;
- }
- else if (bitset(SFF_SETUIDOK, flags) &&
- !bitset(S_IXUSR|S_IXGRP|S_IXOTH, st->st_mode) &&
- S_ISREG(st->st_mode))
- {
- /*
- ** If final file is set-user-ID, run as the owner of that
- ** file. Gotta be careful not to reveal anything too
- ** soon here!
- */
-
-# ifdef SUID_ROOT_FILES_OK
- if (bitset(S_ISUID, st->st_mode))
-# else /* SUID_ROOT_FILES_OK */
- if (bitset(S_ISUID, st->st_mode) && st->st_uid != 0 &&
- st->st_uid != TrustedUid)
-# endif /* SUID_ROOT_FILES_OK */
- {
- uid = st->st_uid;
- user = NULL;
- }
-# ifdef SUID_ROOT_FILES_OK
- if (bitset(S_ISGID, st->st_mode))
-# else /* SUID_ROOT_FILES_OK */
- if (bitset(S_ISGID, st->st_mode) && st->st_gid != 0)
-# endif /* SUID_ROOT_FILES_OK */
- gid = st->st_gid;
- }
-
- checkpath = !bitset(SFF_NOPATHCHECK, flags) ||
- (uid == 0 && !bitset(SFF_ROOTOK|SFF_OPENASROOT, flags));
- if (bitset(SFF_NOWLINK, flags) && !bitset(SFF_SAFEDIRPATH, flags))
- {
- int ret;
-
- /* check the directory */
- p = strrchr(fn, '/');
- if (p == NULL)
- {
- ret = safedirpath(".", uid, gid, user,
- flags|SFF_SAFEDIRPATH, 0, 0);
- }
- else
- {
- *p = '\0';
- ret = safedirpath(fn, uid, gid, user,
- flags|SFF_SAFEDIRPATH, 0, 0);
- *p = '/';
- }
- if (ret == 0)
- {
- /* directory is safe */
- checkpath = false;
- }
- else
- {
-# if HASLSTAT
- /* Need lstat() information if called stat() before */
- if (!bitset(SFF_NOSLINK, flags) && lstat(fn, st) < 0)
- {
- ret = errno;
- if (tTd(44, 4))
- sm_dprintf("\t%s\n", sm_errstring(ret));
- return ret;
- }
-# endif /* HASLSTAT */
- /* directory is writable: disallow links */
- flags |= SFF_NOLINK;
- }
- }
-
- if (checkpath)
- {
- int ret;
-
- p = strrchr(fn, '/');
- if (p == NULL)
- {
- ret = safedirpath(".", uid, gid, user, flags, 0, 0);
- }
- else
- {
- *p = '\0';
- ret = safedirpath(fn, uid, gid, user, flags, 0, 0);
- *p = '/';
- }
- if (ret != 0)
- return ret;
- }
-
- /*
- ** If the target file doesn't exist, check the directory to
- ** ensure that it is writable by this user.
- */
-
- if (file_errno != 0)
- {
- int ret = file_errno;
- char *dir = fn;
-
- if (tTd(44, 4))
- sm_dprintf("\t%s\n", sm_errstring(ret));
-
- errno = 0;
- if (!bitset(SFF_CREAT, flags) || file_errno != ENOENT)
- return ret;
-
- /* check to see if legal to create the file */
- p = strrchr(dir, '/');
- if (p == NULL)
- dir = ".";
- else if (p == dir)
- dir = "/";
- else
- *p = '\0';
- if (stat(dir, &stbuf) >= 0)
- {
- int md = S_IWRITE|S_IEXEC;
-
- ret = 0;
- if (stbuf.st_uid == uid)
- /* EMPTY */
- ;
- else if (uid == 0 && stbuf.st_uid == TrustedUid)
- /* EMPTY */
- ;
- else
- {
- md >>= 3;
- if (stbuf.st_gid == gid)
- /* EMPTY */
- ;
-# ifndef NO_GROUP_SET
- else if (user != NULL && !DontInitGroups &&
- ((gr != NULL &&
- gr->gr_gid == stbuf.st_gid) ||
- (gr = getgrgid(stbuf.st_gid)) != NULL))
- {
- register char **gp;
-
- for (gp = gr->gr_mem; *gp != NULL; gp++)
- if (strcmp(*gp, user) == 0)
- break;
- if (*gp == NULL)
- md >>= 3;
- }
-# endif /* ! NO_GROUP_SET */
- else
- md >>= 3;
- }
- if ((stbuf.st_mode & md) != md)
- ret = errno = EACCES;
- }
- else
- ret = errno;
- if (tTd(44, 4))
- sm_dprintf("\t[final dir %s uid %d mode %lo] %s\n",
- dir, (int) stbuf.st_uid,
- (unsigned long) stbuf.st_mode,
- sm_errstring(ret));
- if (p != NULL)
- *p = '/';
- st->st_mode = ST_MODE_NOFILE;
- return ret;
- }
-
-# ifdef S_ISLNK
- if (bitset(SFF_NOSLINK, flags) && S_ISLNK(st->st_mode))
- {
- if (tTd(44, 4))
- sm_dprintf("\t[slink mode %lo]\tE_SM_NOSLINK\n",
- (unsigned long) st->st_mode);
- return E_SM_NOSLINK;
- }
-# endif /* S_ISLNK */
- if (bitset(SFF_REGONLY, flags) && !S_ISREG(st->st_mode))
- {
- if (tTd(44, 4))
- sm_dprintf("\t[non-reg mode %lo]\tE_SM_REGONLY\n",
- (unsigned long) st->st_mode);
- return E_SM_REGONLY;
- }
- if (bitset(SFF_NOGWFILES, flags) &&
- bitset(S_IWGRP, st->st_mode))
- {
- if (tTd(44, 4))
- sm_dprintf("\t[write bits %lo]\tE_SM_GWFILE\n",
- (unsigned long) st->st_mode);
- return E_SM_GWFILE;
- }
- if (bitset(SFF_NOWWFILES, flags) &&
- bitset(S_IWOTH, st->st_mode))
- {
- if (tTd(44, 4))
- sm_dprintf("\t[write bits %lo]\tE_SM_WWFILE\n",
- (unsigned long) st->st_mode);
- return E_SM_WWFILE;
- }
- if (bitset(SFF_NOGRFILES, flags) && bitset(S_IRGRP, st->st_mode))
- {
- if (tTd(44, 4))
- sm_dprintf("\t[read bits %lo]\tE_SM_GRFILE\n",
- (unsigned long) st->st_mode);
- return E_SM_GRFILE;
- }
- if (bitset(SFF_NOWRFILES, flags) && bitset(S_IROTH, st->st_mode))
- {
- if (tTd(44, 4))
- sm_dprintf("\t[read bits %lo]\tE_SM_WRFILE\n",
- (unsigned long) st->st_mode);
- return E_SM_WRFILE;
- }
- if (!bitset(SFF_EXECOK, flags) &&
- bitset(S_IWUSR|S_IWGRP|S_IWOTH, mode) &&
- bitset(S_IXUSR|S_IXGRP|S_IXOTH, st->st_mode))
- {
- if (tTd(44, 4))
- sm_dprintf("\t[exec bits %lo]\tE_SM_ISEXEC]\n",
- (unsigned long) st->st_mode);
- return E_SM_ISEXEC;
- }
- if (bitset(SFF_NOHLINK, flags) && st->st_nlink != 1)
- {
- if (tTd(44, 4))
- sm_dprintf("\t[link count %d]\tE_SM_NOHLINK\n",
- (int) st->st_nlink);
- return E_SM_NOHLINK;
- }
-
- if (uid == 0 && bitset(SFF_OPENASROOT, flags))
- /* EMPTY */
- ;
- else if (uid == 0 && !bitset(SFF_ROOTOK, flags))
- mode >>= 6;
- else if (st->st_uid == uid)
- /* EMPTY */
- ;
- else if (uid == 0 && st->st_uid == TrustedUid)
- /* EMPTY */
- ;
- else
- {
- mode >>= 3;
- if (st->st_gid == gid)
- /* EMPTY */
- ;
-# ifndef NO_GROUP_SET
- else if (user != NULL && !DontInitGroups &&
- ((gr != NULL && gr->gr_gid == st->st_gid) ||
- (gr = getgrgid(st->st_gid)) != NULL))
- {
- register char **gp;
-
- for (gp = gr->gr_mem; *gp != NULL; gp++)
- if (strcmp(*gp, user) == 0)
- break;
- if (*gp == NULL)
- mode >>= 3;
- }
-# endif /* ! NO_GROUP_SET */
- else
- mode >>= 3;
- }
- if (tTd(44, 4))
- sm_dprintf("\t[uid %d, nlink %d, stat %lo, mode %lo] ",
- (int) st->st_uid, (int) st->st_nlink,
- (unsigned long) st->st_mode, (unsigned long) mode);
- if ((st->st_uid == uid || st->st_uid == 0 ||
- st->st_uid == TrustedUid ||
- !bitset(SFF_MUSTOWN, flags)) &&
- (st->st_mode & mode) == mode)
- {
- if (tTd(44, 4))
- sm_dprintf("\tOK\n");
- return 0;
- }
- if (tTd(44, 4))
- sm_dprintf("\tEACCES\n");
- return EACCES;
-}
-/*
-** SAFEDIRPATH -- check to make sure a path to a directory is safe
-**
-** Safe means not writable and owned by the right folks.
-**
-** Parameters:
-** fn -- filename to check.
-** uid -- user id to compare against.
-** gid -- group id to compare against.
-** user -- user name to compare against (used for group
-** sets).
-** flags -- modifiers:
-** SFF_ROOTOK -- ok to use root permissions to open.
-** SFF_SAFEDIRPATH -- writable directories are considered
-** to be fatal errors.
-** level -- symlink recursive level.
-** offset -- offset into fn to start checking from.
-**
-** Returns:
-** 0 -- if the directory path is "safe".
-** else -- an error number associated with the path.
-*/
-
-int
-safedirpath(fn, uid, gid, user, flags, level, offset)
- char *fn;
- UID_T uid;
- GID_T gid;
- char *user;
- long flags;
- int level;
- int offset;
-{
- int ret = 0;
- int mode = S_IWOTH;
- char save = '\0';
- char *saveptr = NULL;
- char *p, *enddir;
- register struct group *gr = NULL;
- char s[MAXLINKPATHLEN];
- struct stat stbuf;
-
- /* make sure we aren't in a symlink loop */
- if (level > MAXSYMLINKS)
- return ELOOP;
-
- if (level < 0 || offset < 0 || offset > strlen(fn))
- return EINVAL;
-
- /* special case root directory */
- if (*fn == '\0')
- fn = "/";
-
- if (tTd(44, 4))
- sm_dprintf("safedirpath(%s, uid=%ld, gid=%ld, flags=%lx, level=%d, offset=%d):\n",
- fn, (long) uid, (long) gid, flags, level, offset);
-
- if (!bitnset(DBS_GROUPWRITABLEDIRPATHSAFE, DontBlameSendmail))
- mode |= S_IWGRP;
-
- /* Make a modifiable copy of the filename */
- if (sm_strlcpy(s, fn, sizeof s) >= sizeof s)
- return EINVAL;
-
- p = s + offset;
- while (p != NULL)
- {
- /* put back character */
- if (saveptr != NULL)
- {
- *saveptr = save;
- saveptr = NULL;
- p++;
- }
-
- if (*p == '\0')
- break;
-
- p = strchr(p, '/');
-
- /* Special case for root directory */
- if (p == s)
- {
- save = *(p + 1);
- saveptr = p + 1;
- *(p + 1) = '\0';
- }
- else if (p != NULL)
- {
- save = *p;
- saveptr = p;
- *p = '\0';
- }
-
- /* Heuristic: . and .. have already been checked */
- enddir = strrchr(s, '/');
- if (enddir != NULL &&
- (strcmp(enddir, "/..") == 0 ||
- strcmp(enddir, "/.") == 0))
- continue;
-
- if (tTd(44, 20))
- sm_dprintf("\t[dir %s]\n", s);
-
-# if HASLSTAT
- ret = lstat(s, &stbuf);
-# else /* HASLSTAT */
- ret = stat(s, &stbuf);
-# endif /* HASLSTAT */
- if (ret < 0)
- {
- ret = errno;
- break;
- }
-
-# ifdef S_ISLNK
- /* Follow symlinks */
- if (S_ISLNK(stbuf.st_mode))
- {
- int linklen;
- char *target;
- char buf[MAXPATHLEN];
-
- memset(buf, '\0', sizeof buf);
- linklen = readlink(s, buf, sizeof buf);
- if (linklen < 0)
- {
- ret = errno;
- break;
- }
- if (linklen >= sizeof buf)
- {
- /* file name too long for buffer */
- ret = errno = EINVAL;
- break;
- }
-
- offset = 0;
- if (*buf == '/')
- {
- target = buf;
-
- /* If path is the same, avoid rechecks */
- while (s[offset] == buf[offset] &&
- s[offset] != '\0')
- offset++;
-
- if (s[offset] == '\0' && buf[offset] == '\0')
- {
- /* strings match, symlink loop */
- return ELOOP;
- }
-
- /* back off from the mismatch */
- if (offset > 0)
- offset--;
-
- /* Make sure we are at a directory break */
- if (offset > 0 &&
- s[offset] != '/' &&
- s[offset] != '\0')
- {
- while (buf[offset] != '/' &&
- offset > 0)
- offset--;
- }
- if (offset > 0 &&
- s[offset] == '/' &&
- buf[offset] == '/')
- {
- /* Include the trailing slash */
- offset++;
- }
- }
- else
- {
- char *sptr;
- char fullbuf[MAXLINKPATHLEN];
-
- sptr = strrchr(s, '/');
- if (sptr != NULL)
- {
- *sptr = '\0';
- offset = sptr + 1 - s;
- if (sm_strlcpyn(fullbuf,
- sizeof fullbuf, 2,
- s, "/") >=
- sizeof fullbuf ||
- sm_strlcat(fullbuf, buf,
- sizeof fullbuf) >=
- sizeof fullbuf)
- {
- ret = EINVAL;
- break;
- }
- *sptr = '/';
- }
- else
- {
- if (sm_strlcpy(fullbuf, buf,
- sizeof fullbuf) >=
- sizeof fullbuf)
- {
- ret = EINVAL;
- break;
- }
- }
- target = fullbuf;
- }
- ret = safedirpath(target, uid, gid, user, flags,
- level + 1, offset);
- if (ret != 0)
- break;
-
- /* Don't check permissions on the link file itself */
- continue;
- }
-#endif /* S_ISLNK */
-
- if ((uid == 0 || bitset(SFF_SAFEDIRPATH, flags)) &&
-#ifdef S_ISVTX
- !(bitnset(DBS_TRUSTSTICKYBIT, DontBlameSendmail) &&
- bitset(S_ISVTX, stbuf.st_mode)) &&
-#endif /* S_ISVTX */
- bitset(mode, stbuf.st_mode))
- {
- if (tTd(44, 4))
- sm_dprintf("\t[dir %s] mode %lo ",
- s, (unsigned long) stbuf.st_mode);
- if (bitset(SFF_SAFEDIRPATH, flags))
- {
- if (bitset(S_IWOTH, stbuf.st_mode))
- ret = E_SM_WWDIR;
- else
- ret = E_SM_GWDIR;
- if (tTd(44, 4))
- sm_dprintf("FATAL\n");
- break;
- }
- if (tTd(44, 4))
- sm_dprintf("WARNING\n");
- if (Verbose > 1)
- message("051 WARNING: %s writable directory %s",
- bitset(S_IWOTH, stbuf.st_mode)
- ? "World"
- : "Group",
- s);
- }
- if (uid == 0 && !bitset(SFF_ROOTOK|SFF_OPENASROOT, flags))
- {
- if (bitset(S_IXOTH, stbuf.st_mode))
- continue;
- ret = EACCES;
- break;
- }
-
- /*
- ** Let OS determine access to file if we are not
- ** running as a privileged user. This allows ACLs
- ** to work. Also, if opening as root, assume we can
- ** scan the directory.
- */
- if (geteuid() != 0 || bitset(SFF_OPENASROOT, flags))
- continue;
-
- if (stbuf.st_uid == uid &&
- bitset(S_IXUSR, stbuf.st_mode))
- continue;
- if (stbuf.st_gid == gid &&
- bitset(S_IXGRP, stbuf.st_mode))
- continue;
-# ifndef NO_GROUP_SET
- if (user != NULL && !DontInitGroups &&
- ((gr != NULL && gr->gr_gid == stbuf.st_gid) ||
- (gr = getgrgid(stbuf.st_gid)) != NULL))
- {
- register char **gp;
-
- for (gp = gr->gr_mem; gp != NULL && *gp != NULL; gp++)
- if (strcmp(*gp, user) == 0)
- break;
- if (gp != NULL && *gp != NULL &&
- bitset(S_IXGRP, stbuf.st_mode))
- continue;
- }
-# endif /* ! NO_GROUP_SET */
- if (!bitset(S_IXOTH, stbuf.st_mode))
- {
- ret = EACCES;
- break;
- }
- }
- if (tTd(44, 4))
- sm_dprintf("\t[dir %s] %s\n", fn,
- ret == 0 ? "OK" : sm_errstring(ret));
- return ret;
-}
-/*
-** SAFEOPEN -- do a file open with extra checking
-**
-** Parameters:
-** fn -- the file name to open.
-** omode -- the open-style mode flags.
-** cmode -- the create-style mode flags.
-** sff -- safefile flags.
-**
-** Returns:
-** Same as open.
-*/
-
-int
-safeopen(fn, omode, cmode, sff)
- char *fn;
- int omode;
- int cmode;
- long sff;
-{
- int rval;
- int fd;
- int smode;
- struct stat stb;
-
- if (tTd(44, 10))
- sm_dprintf("safeopen: fn=%s, omode=%x, cmode=%x, sff=%lx\n",
- fn, omode, cmode, sff);
-
- if (bitset(O_CREAT, omode))
- sff |= SFF_CREAT;
- omode &= ~O_CREAT;
- smode = 0;
- switch (omode & O_ACCMODE)
- {
- case O_RDONLY:
- smode = S_IREAD;
- break;
-
- case O_WRONLY:
- smode = S_IWRITE;
- break;
-
- case O_RDWR:
- smode = S_IREAD|S_IWRITE;
- break;
-
- default:
- smode = 0;
- break;
- }
- if (bitset(SFF_OPENASROOT, sff))
- rval = safefile(fn, RunAsUid, RunAsGid, RunAsUserName,
- sff, smode, &stb);
- else
- rval = safefile(fn, RealUid, RealGid, RealUserName,
- sff, smode, &stb);
- if (rval != 0)
- {
- errno = rval;
- return -1;
- }
- if (stb.st_mode == ST_MODE_NOFILE && bitset(SFF_CREAT, sff))
- omode |= O_CREAT | (bitset(SFF_NOTEXCL, sff) ? 0 : O_EXCL);
- else if (bitset(SFF_CREAT, sff) && bitset(O_EXCL, omode))
- {
- /* The file exists so an exclusive create would fail */
- errno = EEXIST;
- return -1;
- }
-
- fd = dfopen(fn, omode, cmode, sff);
- if (fd < 0)
- return fd;
- if (filechanged(fn, fd, &stb))
- {
- syserr("554 5.3.0 cannot open: file %s changed after open", fn);
- (void) close(fd);
- errno = E_SM_FILECHANGE;
- return -1;
- }
- return fd;
-}
-/*
-** SAFEFOPEN -- do a file open with extra checking
-**
-** Parameters:
-** fn -- the file name to open.
-** omode -- the open-style mode flags.
-** cmode -- the create-style mode flags.
-** sff -- safefile flags.
-**
-** Returns:
-** Same as fopen.
-*/
-
-SM_FILE_T *
-safefopen(fn, omode, cmode, sff)
- char *fn;
- int omode;
- int cmode;
- long sff;
-{
- int fd;
- int save_errno;
- SM_FILE_T *fp;
- int fmode;
-
- switch (omode & O_ACCMODE)
- {
- case O_RDONLY:
- fmode = SM_IO_RDONLY;
- break;
-
- case O_WRONLY:
- if (bitset(O_APPEND, omode))
- fmode = SM_IO_APPEND;
- else
- fmode = SM_IO_WRONLY;
- break;
-
- case O_RDWR:
- if (bitset(O_TRUNC, omode))
- fmode = SM_IO_RDWRTR;
- else if (bitset(O_APPEND, omode))
- fmode = SM_IO_APPENDRW;
- else
- fmode = SM_IO_RDWR;
- break;
-
- default:
- syserr("554 5.3.5 safefopen: unknown omode %o", omode);
- fmode = 0;
- }
- fd = safeopen(fn, omode, cmode, sff);
- if (fd < 0)
- {
- save_errno = errno;
- if (tTd(44, 10))
- sm_dprintf("safefopen: safeopen failed: %s\n",
- sm_errstring(errno));
- errno = save_errno;
- return NULL;
- }
- fp = sm_io_open(SmFtStdiofd, SM_TIME_DEFAULT,
- (void *) &fd, fmode, NULL);
- if (fp != NULL)
- return fp;
-
- save_errno = errno;
- if (tTd(44, 10))
- {
- sm_dprintf("safefopen: fdopen(%s, %d) failed: omode=%x, sff=%lx, err=%s\n",
- fn, fmode, omode, sff, sm_errstring(errno));
- }
- (void) close(fd);
- errno = save_errno;
- return NULL;
-}
-/*
-** FILECHANGED -- check to see if file changed after being opened
-**
-** Parameters:
-** fn -- pathname of file to check.
-** fd -- file descriptor to check.
-** stb -- stat structure from before open.
-**
-** Returns:
-** true -- if a problem was detected.
-** false -- if this file is still the same.
-*/
-
-bool
-filechanged(fn, fd, stb)
- char *fn;
- int fd;
- struct stat *stb;
-{
- struct stat sta;
-
- if (stb->st_mode == ST_MODE_NOFILE)
- {
-# if HASLSTAT && BOGUS_O_EXCL
- /* only necessary if exclusive open follows symbolic links */
- if (lstat(fn, stb) < 0 || stb->st_nlink != 1)
- return true;
-# else /* HASLSTAT && BOGUS_O_EXCL */
- return false;
-# endif /* HASLSTAT && BOGUS_O_EXCL */
- }
- if (fstat(fd, &sta) < 0)
- return true;
-
- if (sta.st_nlink != stb->st_nlink ||
- sta.st_dev != stb->st_dev ||
- sta.st_ino != stb->st_ino ||
-# if HAS_ST_GEN && 0 /* AFS returns garbage in st_gen */
- sta.st_gen != stb->st_gen ||
-# endif /* HAS_ST_GEN && 0 */
- sta.st_uid != stb->st_uid ||
- sta.st_gid != stb->st_gid)
- {
- if (tTd(44, 8))
- {
- sm_dprintf("File changed after opening:\n");
- sm_dprintf(" nlink = %ld/%ld\n",
- (long) stb->st_nlink, (long) sta.st_nlink);
- sm_dprintf(" dev = %ld/%ld\n",
- (long) stb->st_dev, (long) sta.st_dev);
- sm_dprintf(" ino = %llu/%llu\n",
- (ULONGLONG_T) stb->st_ino,
- (ULONGLONG_T) sta.st_ino);
-# if HAS_ST_GEN
- sm_dprintf(" gen = %ld/%ld\n",
- (long) stb->st_gen, (long) sta.st_gen);
-# endif /* HAS_ST_GEN */
- sm_dprintf(" uid = %ld/%ld\n",
- (long) stb->st_uid, (long) sta.st_uid);
- sm_dprintf(" gid = %ld/%ld\n",
- (long) stb->st_gid, (long) sta.st_gid);
- }
- return true;
- }
-
- return false;
-}
-/*
-** DFOPEN -- determined file open
-**
-** This routine has the semantics of open, except that it will
-** keep trying a few times to make this happen. The idea is that
-** on very loaded systems, we may run out of resources (inodes,
-** whatever), so this tries to get around it.
-*/
-
-int
-dfopen(filename, omode, cmode, sff)
- char *filename;
- int omode;
- int cmode;
- long sff;
-{
- register int tries;
- int fd = -1;
- struct stat st;
-
- for (tries = 0; tries < 10; tries++)
- {
- (void) sleep((unsigned) (10 * tries));
- errno = 0;
- fd = open(filename, omode, cmode);
- if (fd >= 0)
- break;
- switch (errno)
- {
- case ENFILE: /* system file table full */
- case EINTR: /* interrupted syscall */
-#ifdef ETXTBSY
- case ETXTBSY: /* Apollo: net file locked */
-#endif /* ETXTBSY */
- continue;
- }
- break;
- }
- if (!bitset(SFF_NOLOCK, sff) &&
- fd >= 0 &&
- fstat(fd, &st) >= 0 &&
- S_ISREG(st.st_mode))
- {
- int locktype;
-
- /* lock the file to avoid accidental conflicts */
- if ((omode & O_ACCMODE) != O_RDONLY)
- locktype = LOCK_EX;
- else
- locktype = LOCK_SH;
- if (!lockfile(fd, filename, NULL, locktype))
- {
- int save_errno = errno;
-
- (void) close(fd);
- fd = -1;
- errno = save_errno;
- }
- else
- errno = 0;
- }
- return fd;
-}
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-05 04:38:13 +0000