summaryrefslogtreecommitdiffstats
path: root/src/sesh.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/sesh.c')
-rw-r--r--src/sesh.c268
1 files changed, 268 insertions, 0 deletions
diff --git a/src/sesh.c b/src/sesh.c
new file mode 100644
index 0000000..873748e
--- /dev/null
+++ b/src/sesh.c
@@ -0,0 +1,268 @@
+/*
+ * Copyright (c) 2008, 2010-2018 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>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <signal.h>
+#include <time.h>
+#include <unistd.h>
+#ifdef HAVE_STDBOOL_H
+# include <stdbool.h>
+#else
+# include "compat/stdbool.h"
+#endif /* HAVE_STDBOOL_H */
+
+#include "sudo_gettext.h" /* must be included before sudo_compat.h */
+
+#include "sudo_compat.h"
+#include "sudo_fatal.h"
+#include "sudo_conf.h"
+#include "sudo_debug.h"
+#include "sudo_exec.h"
+#include "sudo_plugin.h"
+#include "sudo_util.h"
+
+__dso_public int main(int argc, char *argv[], char *envp[]);
+
+static int sesh_sudoedit(int argc, char *argv[]);
+
+/*
+ * Exit codes defined in sudo_exec.h:
+ * SESH_SUCCESS (0) ... successful operation
+ * SESH_ERR_FAILURE (1) ... unspecified error
+ * SESH_ERR_INVALID (30) ... invalid -e arg value
+ * SESH_ERR_BAD_PATHS (31) ... odd number of paths
+ * SESH_ERR_NO_FILES (32) ... copy error, no files copied
+ * SESH_ERR_SOME_FILES (33) ... copy error, no files copied
+ */
+int
+main(int argc, char *argv[], char *envp[])
+{
+ int ret;
+ debug_decl(main, SUDO_DEBUG_MAIN)
+
+ initprogname(argc > 0 ? argv[0] : "sesh");
+
+ setlocale(LC_ALL, "");
+ bindtextdomain(PACKAGE_NAME, LOCALEDIR);
+ textdomain(PACKAGE_NAME);
+
+ if (argc < 2)
+ sudo_fatalx(U_("requires at least one argument"));
+
+ /* Read sudo.conf and initialize the debug subsystem. */
+ if (sudo_conf_read(NULL, SUDO_CONF_DEBUG) == -1)
+ exit(EXIT_FAILURE);
+ sudo_debug_register(getprogname(), NULL, NULL,
+ sudo_conf_debug_files(getprogname()));
+
+ if (strcmp(argv[1], "-e") == 0) {
+ ret = sesh_sudoedit(argc, argv);
+ } else {
+ bool login_shell, noexec = false;
+ char *cp, *cmnd;
+ int fd = -1;
+
+ /* If the first char of argv[0] is '-', we are running a login shell. */
+ login_shell = argv[0][0] == '-';
+
+ /* If argv[0] ends in -noexec, pass the flag to sudo_execve() */
+ if ((cp = strrchr(argv[0], '-')) != NULL && cp != argv[0])
+ noexec = strcmp(cp, "-noexec") == 0;
+
+ /* If argv[1] is --execfd=%d, extract the fd to exec with. */
+ if (strncmp(argv[1], "--execfd=", 9) == 0) {
+ const char *errstr;
+
+ cp = argv[1] + 9;
+ fd = strtonum(cp, 0, INT_MAX, &errstr);
+ if (errstr != NULL)
+ sudo_fatalx(U_("invalid file descriptor number: %s"), cp);
+ argv++;
+ argc--;
+ }
+
+ /* Shift argv and make a copy of the command to execute. */
+ argv++;
+ argc--;
+ if ((cmnd = strdup(argv[0])) == NULL)
+ sudo_fatalx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
+
+ /* If invoked as a login shell, modify argv[0] accordingly. */
+ if (login_shell) {
+ if ((cp = strrchr(argv[0], '/')) == NULL)
+ sudo_fatal(U_("unable to run %s as a login shell"), argv[0]);
+ *cp = '-';
+ argv[0] = cp;
+ }
+ sudo_execve(fd, cmnd, argv, envp, noexec);
+ sudo_warn(U_("unable to execute %s"), cmnd);
+ ret = SESH_ERR_FAILURE;
+ }
+ sudo_debug_exit_int(__func__, __FILE__, __LINE__, sudo_debug_subsys, ret);
+ _exit(ret);
+}
+
+static int
+sesh_sudoedit(int argc, char *argv[])
+{
+ int i, oflags_dst, post, ret = SESH_ERR_FAILURE;
+ int fd_src = -1, fd_dst = -1, follow = 0;
+ ssize_t nread, nwritten;
+ struct stat sb;
+ struct timespec times[2];
+ char buf[BUFSIZ];
+ debug_decl(sesh_sudoedit, SUDO_DEBUG_EDIT)
+
+ /* Check for -h flag (don't follow links). */
+ if (strcmp(argv[2], "-h") == 0) {
+ argv++;
+ argc--;
+ follow = O_NOFOLLOW;
+ }
+
+ if (argc < 3)
+ debug_return_int(SESH_ERR_FAILURE);
+
+ /*
+ * We need to know whether we are performing the copy operation
+ * before or after the editing. Without this we would not know
+ * which files are temporary and which are the originals.
+ * post = 0 ... before
+ * post = 1 ... after
+ */
+ if (strcmp(argv[2], "0") == 0)
+ post = 0;
+ else if (strcmp(argv[2], "1") == 0)
+ post = 1;
+ else /* invalid value */
+ debug_return_int(SESH_ERR_INVALID);
+
+ /* Align argv & argc to the beggining of the file list. */
+ argv += 3;
+ argc -= 3;
+
+ /* no files specified, nothing to do */
+ if (argc == 0)
+ debug_return_int(SESH_SUCCESS);
+ /* odd number of paths specified */
+ if (argc & 1)
+ debug_return_int(SESH_ERR_BAD_PATHS);
+
+ /*
+ * Use O_EXCL if we are not in the post editing stage
+ * so that it's ensured that the temporary files are
+ * created by us and that we are not opening any symlinks.
+ */
+ oflags_dst = O_WRONLY|O_TRUNC|O_CREAT|(post ? follow : O_EXCL);
+ for (i = 0; i < argc - 1; i += 2) {
+ const char *path_src = argv[i];
+ const char *path_dst = argv[i + 1];
+ /*
+ * Try to open the source file for reading. If it
+ * doesn't exist, that's OK, we'll create an empty
+ * destination file.
+ */
+ if ((fd_src = open(path_src, O_RDONLY|follow, S_IRUSR|S_IWUSR)) < 0) {
+ if (errno != ENOENT) {
+ sudo_warn("%s", path_src);
+ if (post) {
+ ret = SESH_ERR_SOME_FILES;
+ goto nocleanup;
+ } else
+ goto cleanup_0;
+ }
+ }
+
+ if ((fd_dst = open(path_dst, oflags_dst, post ?
+ (S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH) : (S_IRUSR|S_IWUSR))) < 0) {
+ /* error - cleanup */
+ sudo_warn("%s", path_dst);
+ if (post) {
+ ret = SESH_ERR_SOME_FILES;
+ goto nocleanup;
+ } else
+ goto cleanup_0;
+ }
+
+ if (fd_src != -1) {
+ while ((nread = read(fd_src, buf, sizeof(buf))) > 0) {
+ if ((nwritten = write(fd_dst, buf, nread)) != nread) {
+ sudo_warn("%s", path_src);
+ if (post) {
+ ret = SESH_ERR_SOME_FILES;
+ goto nocleanup;
+ } else
+ goto cleanup_0;
+ }
+ }
+ }
+
+ if (!post) {
+ if (fd_src == -1 || fstat(fd_src, &sb) != 0)
+ memset(&sb, 0, sizeof(sb));
+ /* Make mtime on temp file match src. */
+ mtim_get(&sb, times[0]);
+ times[1].tv_sec = times[0].tv_sec;
+ times[1].tv_nsec = times[0].tv_nsec;
+ if (futimens(fd_dst, times) == -1) {
+ if (utimensat(AT_FDCWD, path_dst, times, 0) == -1)
+ sudo_warn("%s", path_dst);
+ }
+ }
+ close(fd_dst);
+ fd_dst = -1;
+ if (fd_src != -1) {
+ close(fd_src);
+ fd_src = -1;
+ }
+ }
+
+ ret = SESH_SUCCESS;
+ if (post) {
+ /* Remove temporary files (post=1) */
+ for (i = 0; i < argc - 1; i += 2)
+ unlink(argv[i]);
+ }
+nocleanup:
+ if (fd_dst != -1)
+ close(fd_dst);
+ if (fd_src != -1)
+ close(fd_src);
+ return(ret);
+cleanup_0:
+ /* Remove temporary files (post=0) */
+ for (i = 0; i < argc - 1; i += 2)
+ unlink(argv[i + 1]);
+ if (fd_dst != -1)
+ close(fd_dst);
+ if (fd_src != -1)
+ close(fd_src);
+ return(SESH_ERR_NO_FILES);
+}