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-rw-r--r--Linux-PAM/modules/pam_issue/pam_issue.c308
1 files changed, 308 insertions, 0 deletions
diff --git a/Linux-PAM/modules/pam_issue/pam_issue.c b/Linux-PAM/modules/pam_issue/pam_issue.c
new file mode 100644
index 00000000..1f4853de
--- /dev/null
+++ b/Linux-PAM/modules/pam_issue/pam_issue.c
@@ -0,0 +1,308 @@
+/* pam_issue module - a simple /etc/issue parser to set PAM_USER_PROMPT
+ *
+ * Copyright 1999 by Ben Collins <bcollins@debian.org>
+ *
+ * Needs to be called before any other auth modules so we can setup the
+ * user prompt before it's first used. Allows one argument option, which
+ * is the full path to a file to be used for issue (uses /etc/issue as a
+ * default) such as "issue=/etc/issue.telnet".
+ *
+ * We can also parse escapes within the the issue file (enabled by
+ * default, but can be disabled with the "noesc" option). It's the exact
+ * same parsing as util-linux's agetty program performs.
+ *
+ * Released under the GNU LGPL version 2 or later
+ */
+
+#define _GNU_SOURCE
+#define _BSD_SOURCE
+
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/utsname.h>
+#include <utmp.h>
+#include <malloc.h>
+#include <time.h>
+
+#include <security/_pam_macros.h>
+
+#define PAM_SM_AUTH
+
+#include <security/pam_modules.h>
+
+static int _user_prompt_set = 0;
+
+char *do_prompt (FILE *);
+
+/* --- authentication management functions (only) --- */
+
+PAM_EXTERN
+int pam_sm_authenticate(pam_handle_t *pamh, int flags, int argc,
+ const char **argv)
+{
+ int retval = PAM_SUCCESS;
+ FILE *fd;
+ int parse_esc = 1;
+ char *prompt_tmp = NULL;
+ const char *cur_prompt = NULL;
+ struct stat st;
+ char *issue_file = NULL;
+
+ /* If we've already set the prompt, don't set it again */
+ if(_user_prompt_set)
+ return PAM_IGNORE;
+ else
+ /* we set this here so if we fail below, we wont get further
+ than this next time around (only one real failure) */
+ _user_prompt_set = 1;
+
+ for ( ; argc-- > 0 ; ++argv ) {
+ if (!strncmp(*argv,"issue=",6)) {
+ issue_file = (char *) strdup(6+*argv);
+ if (issue_file != NULL) {
+ D(("set issue_file to: %s", issue_file));
+ } else {
+ D(("failed to strdup issue_file - ignored"));
+ return PAM_IGNORE;
+ }
+ } else if (!strcmp(*argv,"noesc")) {
+ parse_esc = 0;
+ D(("turning off escape parsing by request"));
+ } else
+ D(("unknown option passed: %s", *argv));
+ }
+
+ if (issue_file == NULL)
+ issue_file = strdup("/etc/issue");
+
+ if ((fd = fopen(issue_file, "r")) != NULL) {
+ int tot_size = 0;
+
+ if (fstat(fileno(fd), &st) < 0)
+ return PAM_IGNORE;
+
+ retval = pam_get_item(pamh, PAM_USER_PROMPT,
+ (const void **) &cur_prompt);
+ if (retval != PAM_SUCCESS) {
+ return PAM_IGNORE;
+ }
+ if (cur_prompt == NULL) {
+ cur_prompt = "";
+ }
+
+ /* first read in the issue file */
+
+ if (parse_esc) {
+ prompt_tmp = do_prompt(fd);
+ if (prompt_tmp == NULL) {
+ return PAM_IGNORE;
+ }
+ } else {
+ int count = 0;
+
+ prompt_tmp = malloc(st.st_size + 1);
+ if (prompt_tmp == NULL) {
+ return PAM_IGNORE;
+ }
+ memset (prompt_tmp, '\0', st.st_size + 1);
+ count = fread(prompt_tmp, sizeof(char *), st.st_size, fd);
+ if (count != st.st_size) {
+ free(prompt_tmp);
+ return PAM_IGNORE;
+ }
+ prompt_tmp[st.st_size] = '\0';
+ }
+
+ fclose(fd);
+
+ tot_size = strlen(prompt_tmp) + strlen(cur_prompt) + 1;
+
+ /*
+ * alloc some extra space for the original prompt
+ * and postpend it to the buffer
+ */
+ {
+ char *prompt_tmp_tmp = prompt_tmp;
+
+ prompt_tmp = realloc(prompt_tmp, tot_size);
+ if (prompt_tmp == NULL) {
+ prompt_tmp = prompt_tmp_tmp;
+ retval = PAM_IGNORE;
+ goto cleanup;
+ }
+ }
+
+ strcpy(prompt_tmp+strlen(prompt_tmp), cur_prompt);
+
+ prompt_tmp[tot_size] = '\0';
+
+ retval = pam_set_item(pamh, PAM_USER_PROMPT,
+ (const char *) prompt_tmp);
+
+ cleanup:
+ free(issue_file);
+ free(prompt_tmp);
+
+ } else {
+ D(("could not open issue_file: %s", issue_file));
+ return PAM_IGNORE;
+ }
+
+ return retval;
+}
+
+PAM_EXTERN
+int pam_sm_setcred(pam_handle_t *pamh, int flags, int argc,
+ const char **argv)
+{
+ return PAM_IGNORE;
+}
+
+char *do_prompt(FILE *fd)
+{
+ int c, size = 1024;
+ char *issue = (char *)malloc(size);
+ char buf[1024];
+ struct utsname uts;
+
+ if (issue == NULL || fd == NULL)
+ return NULL;
+
+ issue[0] = '\0'; /* zero this, for strcat to work on first buf */
+ (void) uname(&uts);
+
+ while ((c = getc(fd)) != EOF) {
+ if (c == '\\') {
+ c = getc(fd);
+ switch (c) {
+ case 's':
+ snprintf (buf, 1024, "%s", uts.sysname);
+ break;
+ case 'n':
+ snprintf (buf, 1024, "%s", uts.nodename);
+ break;
+ case 'r':
+ snprintf (buf, 1024, "%s", uts.release);
+ break;
+ case 'v':
+ snprintf (buf, 1024, "%s", uts.version);
+ break;
+ case 'm':
+ snprintf (buf, 1024, "%s", uts.machine);
+ break;
+ case 'o':
+ {
+ char domainname[256];
+
+ getdomainname(domainname, sizeof(domainname));
+ domainname[sizeof(domainname)-1] = '\0';
+ snprintf (buf, 1024, "%s", domainname);
+ }
+ break;
+
+ case 'd':
+ case 't':
+ {
+ const char *weekday[] = {
+ "Sun", "Mon", "Tue", "Wed", "Thu",
+ "Fri", "Sat" };
+ const char *month[] = {
+ "Jan", "Feb", "Mar", "Apr", "May",
+ "Jun", "Jul", "Aug", "Sep", "Oct",
+ "Nov", "Dec" };
+ time_t now;
+ struct tm *tm;
+
+ (void) time (&now);
+ tm = localtime(&now);
+
+ if (c == 'd')
+ snprintf (buf, 1024, "%s %s %d %d",
+ weekday[tm->tm_wday], month[tm->tm_mon],
+ tm->tm_mday,
+ tm->tm_year + 1900);
+ else
+ snprintf (buf, 1024, "%02d:%02d:%02d",
+ tm->tm_hour, tm->tm_min, tm->tm_sec);
+ }
+ break;
+ case 'l':
+ {
+ char *ttyn = ttyname(1);
+ if (!strncmp(ttyn, "/dev/", 5))
+ ttyn += 5;
+ snprintf (buf, 1024, "%s", ttyn);
+ }
+ break;
+ case 'u':
+ case 'U':
+ {
+ int users = 0;
+ struct utmp *ut;
+ setutent();
+ while ((ut = getutent()))
+ if (ut->ut_type == USER_PROCESS)
+ users++;
+ endutent();
+ printf ("%d ", users);
+ if (c == 'U')
+ snprintf (buf, 1024, "%s", (users == 1) ?
+ " user" : " users");
+ break;
+ }
+ default:
+ buf[0] = c; buf[1] = '\0';
+ }
+ if ((strlen(issue) + strlen(buf)) < size + 1) {
+ char *old_issue = issue;
+
+ size += strlen(buf) + 1;
+ issue = (char *) realloc (issue, size);
+ if (issue == NULL) {
+ free(old_issue);
+ return NULL;
+ }
+ }
+ strcat(issue, buf);
+ } else {
+ buf[0] = c; buf[1] = '\0';
+ if ((strlen(issue) + strlen(buf)) < size + 1) {
+ char *old_issue = issue;
+
+ size += strlen(buf) + 1;
+ issue = (char *) realloc (issue, size);
+ if (issue == NULL) {
+ free(old_issue);
+ return NULL;
+ }
+ }
+ strcat(issue, buf);
+ }
+ }
+
+ return issue;
+}
+
+#ifdef PAM_STATIC
+
+/* static module data */
+
+struct pam_module _pam_issue_modstruct = {
+ "pam_issue",
+ pam_sm_authenticate,
+ pam_sm_setcred,
+ NULL,
+ NULL,
+ NULL,
+ NULL,
+};
+
+#endif
+
+/* end of module definition */
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