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-rw-r--r--src/ttyname.c336
1 files changed, 336 insertions, 0 deletions
diff --git a/src/ttyname.c b/src/ttyname.c
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index 0000000..580bafd
--- /dev/null
+++ b/src/ttyname.c
@@ -0,0 +1,336 @@
+/*
+ * Copyright (c) 2012-2018 Todd C. Miller <Todd.Miller@sudo.ws>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*
+ * This is an open source non-commercial project. Dear PVS-Studio, please check it.
+ * PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
+ */
+
+#include <config.h>
+
+/* Large files not supported by procfs.h on Solaris. */
+#if defined(HAVE_STRUCT_PSINFO_PR_TTYDEV)
+# undef _FILE_OFFSET_BITS
+# undef _LARGE_FILES
+#endif
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#if defined(MAJOR_IN_MKDEV)
+# include <sys/mkdev.h>
+#elif defined(MAJOR_IN_SYSMACROS)
+# include <sys/sysmacros.h>
+#endif
+#include <stdio.h>
+#include <stdlib.h>
+#ifdef HAVE_STRING_H
+# include <string.h>
+#endif /* HAVE_STRING_H */
+#ifdef HAVE_STRINGS_H
+# include <strings.h>
+#endif /* HAVE_STRINGS_H */
+#include <unistd.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <dirent.h>
+#if defined(HAVE_KINFO_PROC2_NETBSD) || defined (HAVE_KINFO_PROC_OPENBSD) || defined(HAVE_KINFO_PROC_44BSD)
+# include <sys/sysctl.h>
+#elif defined(HAVE_KINFO_PROC_FREEBSD)
+# include <sys/sysctl.h>
+# include <sys/user.h>
+#endif
+#if defined(HAVE_PROCFS_H)
+# include <procfs.h>
+#elif defined(HAVE_SYS_PROCFS_H)
+# include <sys/procfs.h>
+#endif
+#ifdef HAVE_PSTAT_GETPROC
+# include <sys/pstat.h>
+#endif
+
+#include "sudo.h"
+
+/*
+ * How to access the tty device number in struct kinfo_proc.
+ */
+#if defined(HAVE_KINFO_PROC2_NETBSD)
+# define SUDO_KERN_PROC KERN_PROC2
+# define sudo_kinfo_proc kinfo_proc2
+# define sudo_kp_tdev p_tdev
+# define sudo_kp_namelen 6
+#elif defined(HAVE_KINFO_PROC_OPENBSD)
+# define SUDO_KERN_PROC KERN_PROC
+# define sudo_kinfo_proc kinfo_proc
+# define sudo_kp_tdev p_tdev
+# define sudo_kp_namelen 6
+#elif defined(HAVE_KINFO_PROC_FREEBSD)
+# define SUDO_KERN_PROC KERN_PROC
+# define sudo_kinfo_proc kinfo_proc
+# define sudo_kp_tdev ki_tdev
+# define sudo_kp_namelen 4
+#elif defined(HAVE_KINFO_PROC_44BSD)
+# define SUDO_KERN_PROC KERN_PROC
+# define sudo_kinfo_proc kinfo_proc
+# define sudo_kp_tdev kp_eproc.e_tdev
+# define sudo_kp_namelen 4
+#endif
+
+#if defined(sudo_kp_tdev)
+/*
+ * Store the name of the tty to which the process is attached in name.
+ * Returns name on success and NULL on failure, setting errno.
+ */
+char *
+get_process_ttyname(char *name, size_t namelen)
+{
+ struct sudo_kinfo_proc *ki_proc = NULL;
+ size_t size = sizeof(*ki_proc);
+ int mib[6], rc, serrno = errno;
+ char *ret = NULL;
+ debug_decl(get_process_ttyname, SUDO_DEBUG_UTIL)
+
+ /*
+ * Lookup controlling tty for this process via sysctl.
+ * This will work even if std{in,out,err} are redirected.
+ */
+ mib[0] = CTL_KERN;
+ mib[1] = SUDO_KERN_PROC;
+ mib[2] = KERN_PROC_PID;
+ mib[3] = (int)getpid();
+ mib[4] = sizeof(*ki_proc);
+ mib[5] = 1;
+ do {
+ struct sudo_kinfo_proc *kp;
+
+ size += size / 10;
+ if ((kp = realloc(ki_proc, size)) == NULL) {
+ rc = -1;
+ break; /* really out of memory. */
+ }
+ ki_proc = kp;
+ rc = sysctl(mib, sudo_kp_namelen, ki_proc, &size, NULL, 0);
+ } while (rc == -1 && errno == ENOMEM);
+ errno = ENOENT;
+ if (rc != -1) {
+ if ((dev_t)ki_proc->sudo_kp_tdev != (dev_t)-1) {
+ errno = serrno;
+ ret = sudo_ttyname_dev(ki_proc->sudo_kp_tdev, name, namelen);
+ if (ret == NULL) {
+ sudo_debug_printf(SUDO_DEBUG_WARN|SUDO_DEBUG_LINENO|SUDO_DEBUG_ERRNO,
+ "unable to map device number %u to name",
+ ki_proc->sudo_kp_tdev);
+ }
+ }
+ } else {
+ sudo_debug_printf(SUDO_DEBUG_WARN|SUDO_DEBUG_LINENO|SUDO_DEBUG_ERRNO,
+ "unable to resolve tty via KERN_PROC");
+ }
+ free(ki_proc);
+
+ debug_return_str(ret);
+}
+#elif defined(HAVE_STRUCT_PSINFO_PR_TTYDEV)
+/*
+ * Store the name of the tty to which the process is attached in name.
+ * Returns name on success and NULL on failure, setting errno.
+ */
+char *
+get_process_ttyname(char *name, size_t namelen)
+{
+ char path[PATH_MAX], *ret = NULL;
+ struct psinfo psinfo;
+ ssize_t nread;
+ int fd, serrno = errno;
+ debug_decl(get_process_ttyname, SUDO_DEBUG_UTIL)
+
+ /* Try to determine the tty from pr_ttydev in /proc/pid/psinfo. */
+ snprintf(path, sizeof(path), "/proc/%u/psinfo", (unsigned int)getpid());
+ if ((fd = open(path, O_RDONLY, 0)) != -1) {
+ nread = read(fd, &psinfo, sizeof(psinfo));
+ close(fd);
+ if (nread == (ssize_t)sizeof(psinfo)) {
+ dev_t rdev = (dev_t)psinfo.pr_ttydev;
+#if defined(_AIX) && defined(DEVNO64)
+ if ((psinfo.pr_ttydev & DEVNO64) && sizeof(dev_t) == 4)
+ rdev = makedev(major64(psinfo.pr_ttydev), minor64(psinfo.pr_ttydev));
+#endif
+ if (rdev != (dev_t)-1) {
+ errno = serrno;
+ ret = sudo_ttyname_dev(rdev, name, namelen);
+ goto done;
+ }
+ }
+ }
+ errno = ENOENT;
+
+done:
+ if (ret == NULL)
+ sudo_debug_printf(SUDO_DEBUG_WARN|SUDO_DEBUG_LINENO|SUDO_DEBUG_ERRNO,
+ "unable to resolve tty via %s", path);
+
+ debug_return_str(ret);
+}
+#elif defined(__linux__)
+/*
+ * Store the name of the tty to which the process is attached in name.
+ * Returns name on success and NULL on failure, setting errno.
+ */
+char *
+get_process_ttyname(char *name, size_t namelen)
+{
+ const char path[] = "/proc/self/stat";
+ char *cp, buf[1024];
+ char *ret = NULL;
+ int serrno = errno;
+ ssize_t nread;
+ int fd;
+ debug_decl(get_process_ttyname, SUDO_DEBUG_UTIL)
+
+ /*
+ * Try to determine the tty from tty_nr in /proc/self/stat.
+ * Ignore /proc/self/stat if it contains embedded NUL bytes.
+ */
+ if ((fd = open(path, O_RDONLY | O_NOFOLLOW)) != -1) {
+ cp = buf;
+ while ((nread = read(fd, cp, buf + sizeof(buf) - cp)) != 0) {
+ if (nread == -1) {
+ if (errno == EAGAIN || errno == EINTR)
+ continue;
+ break;
+ }
+ cp += nread;
+ if (cp >= buf + sizeof(buf))
+ break;
+ }
+ if (nread == 0 && memchr(buf, '\0', cp - buf) == NULL) {
+ /*
+ * Field 7 is the tty dev (0 if no tty).
+ * Since the process name at field 2 "(comm)" may include
+ * whitespace (including newlines), start at the last ')' found.
+ */
+ *cp = '\0';
+ cp = strrchr(buf, ')');
+ if (cp != NULL) {
+ char *ep = cp;
+ const char *errstr;
+ int field = 1;
+
+ while (*++ep != '\0') {
+ if (*ep == ' ') {
+ *ep = '\0';
+ if (++field == 7) {
+ int tty_nr = strtonum(cp, INT_MIN, INT_MAX, &errstr);
+ if (errstr) {
+ sudo_debug_printf(SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO,
+ "%s: tty device %s: %s", path, cp, errstr);
+ }
+ if (tty_nr != 0) {
+ /*
+ * Avoid sign extension when assigning tdev.
+ * tty_nr in /proc/self/stat is printed as a
+ * signed int but the actual device number is an
+ * unsigned int and dev_t is unsigned long long.
+ */
+ dev_t tdev = (unsigned int)tty_nr;
+ errno = serrno;
+ ret = sudo_ttyname_dev(tdev, name, namelen);
+ goto done;
+ }
+ break;
+ }
+ cp = ep + 1;
+ }
+ }
+ }
+ }
+ }
+ errno = ENOENT;
+
+done:
+ if (fd != -1)
+ close(fd);
+ if (ret == NULL)
+ sudo_debug_printf(SUDO_DEBUG_WARN|SUDO_DEBUG_LINENO|SUDO_DEBUG_ERRNO,
+ "unable to resolve tty via %s", path);
+
+ debug_return_str(ret);
+}
+#elif defined(HAVE_PSTAT_GETPROC)
+/*
+ * Store the name of the tty to which the process is attached in name.
+ * Returns name on success and NULL on failure, setting errno.
+ */
+char *
+get_process_ttyname(char *name, size_t namelen)
+{
+ struct pst_status pstat;
+ char *ret = NULL;
+ int rc, serrno = errno;
+ debug_decl(get_process_ttyname, SUDO_DEBUG_UTIL)
+
+ /*
+ * Determine the tty from psdev in struct pst_status.
+ * We may get EOVERFLOW if the whole thing doesn't fit but that is OK.
+ */
+ rc = pstat_getproc(&pstat, sizeof(pstat), (size_t)0, (int)getpid());
+ if (rc != -1 || errno == EOVERFLOW) {
+ if (pstat.pst_term.psd_major != -1 && pstat.pst_term.psd_minor != -1) {
+ errno = serrno;
+ ret = sudo_ttyname_dev(makedev(pstat.pst_term.psd_major,
+ pstat.pst_term.psd_minor), name, namelen);
+ goto done;
+ }
+ }
+ errno = ENOENT;
+
+done:
+ if (ret == NULL)
+ sudo_debug_printf(SUDO_DEBUG_WARN|SUDO_DEBUG_LINENO|SUDO_DEBUG_ERRNO,
+ "unable to resolve tty via pstat");
+
+ debug_return_str(ret);
+}
+#else
+/*
+ * Store the name of the tty to which the process is attached in name.
+ * Returns name on success and NULL on failure, setting errno.
+ */
+char *
+get_process_ttyname(char *name, size_t namelen)
+{
+ char *tty;
+ debug_decl(get_process_ttyname, SUDO_DEBUG_UTIL)
+
+ if ((tty = ttyname(STDIN_FILENO)) == NULL) {
+ if ((tty = ttyname(STDOUT_FILENO)) == NULL)
+ tty = ttyname(STDERR_FILENO);
+ }
+ if (tty != NULL) {
+ if (strlcpy(name, tty, namelen) < namelen)
+ debug_return_str(name);
+ errno = ERANGE;
+ sudo_debug_printf(SUDO_DEBUG_WARN|SUDO_DEBUG_LINENO|SUDO_DEBUG_ERRNO,
+ "unable to store tty from ttyname");
+ } else {
+ sudo_debug_printf(SUDO_DEBUG_WARN|SUDO_DEBUG_LINENO|SUDO_DEBUG_ERRNO,
+ "unable to resolve tty via ttyname");
+ errno = ENOENT;
+ }
+
+ debug_return_str(NULL);
+}
+#endif