#include <unistd.h>
#include <sys/utsname.h>
#include <utmp.h>
-#include <malloc.h>
#include <time.h>
-
-#include <security/_pam_macros.h>
+#include <syslog.h>
#define PAM_SM_AUTH
+#include <security/_pam_macros.h>
#include <security/pam_modules.h>
+#include <security/pam_ext.h>
static int _user_prompt_set = 0;
-static char *do_prompt (FILE *);
+static int read_issue_raw(pam_handle_t *pamh, FILE *fp, char **prompt);
+static int read_issue_quoted(pam_handle_t *pamh, FILE *fp, char **prompt);
/* --- authentication management functions (only) --- */
pam_sm_authenticate (pam_handle_t *pamh, int flags UNUSED,
int argc, const char **argv)
{
- int retval = PAM_SUCCESS;
- FILE *fd;
+ int retval = PAM_SERVICE_ERR;
+ FILE *fp;
+ const char *issue_file = NULL;
int parse_esc = 1;
- char *prompt_tmp = NULL;
- const void *cur_prompt = NULL;
- struct stat st;
- char *issue_file = NULL;
+ const void *item = NULL;
+ const char *cur_prompt;
+ char *issue_prompt = 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;
+
+ /* 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;
- }
+ issue_file = 6 + *argv;
+ D(("set issue_file to: %s", issue_file));
} else if (!strcmp(*argv,"noesc")) {
parse_esc = 0;
D(("turning off escape parsing by request"));
}
if (issue_file == NULL)
- issue_file = strdup("/etc/issue");
+ issue_file = "/etc/issue";
- if ((fd = fopen(issue_file, "r")) != NULL) {
- int tot_size = 0;
-
- if (fstat(fileno(fd), &st) < 0) {
- fclose(fd);
- if (issue_file)
- free(issue_file);
- return PAM_IGNORE;
- }
+ if ((fp = fopen(issue_file, "r")) == NULL) {
+ pam_syslog(pamh, LOG_ERR, "error opening %s: %m", issue_file);
+ return PAM_SERVICE_ERR;
+ }
- retval = pam_get_item(pamh, PAM_USER_PROMPT, &cur_prompt);
- if (retval != PAM_SUCCESS) {
- fclose(fd);
- if (issue_file)
- free(issue_file);
- return PAM_IGNORE;
- }
- if (cur_prompt == NULL) {
- cur_prompt = "";
- }
+ if ((retval = pam_get_item(pamh, PAM_USER_PROMPT, &item)) != PAM_SUCCESS) {
+ fclose(fp);
+ return retval;
+ }
- /* first read in the issue file */
+ cur_prompt = item;
+ if (cur_prompt == NULL)
+ cur_prompt = "";
- if (parse_esc) {
- prompt_tmp = do_prompt(fd);
- if (prompt_tmp == NULL) {
- fclose(fd);
- if (issue_file)
- free(issue_file);
- return PAM_IGNORE;
- }
- } else {
- int count = 0;
-
- prompt_tmp = malloc(st.st_size + 1);
- if (prompt_tmp == NULL) {
- fclose(fd);
- if (issue_file)
- free(issue_file);
- return PAM_IGNORE;
- }
- memset (prompt_tmp, '\0', st.st_size + 1);
- count = fread(prompt_tmp, 1, st.st_size, fd);
- if (count != st.st_size) {
- fclose(fd);
- retval = PAM_IGNORE;
- goto cleanup;
- }
- prompt_tmp[st.st_size] = '\0';
- }
+ if (parse_esc)
+ retval = read_issue_quoted(pamh, fp, &issue_prompt);
+ else
+ retval = read_issue_raw(pamh, fp, &issue_prompt);
- fclose(fd);
+ fclose(fp);
- tot_size = strlen(prompt_tmp) + strlen(cur_prompt) + 1;
+ if (retval != PAM_SUCCESS)
+ goto out;
- /*
- * alloc some extra space for the original prompt
- * and postpend it to the buffer
- */
- {
- char *prompt_tmp_tmp = prompt_tmp;
+ {
+ size_t size = strlen(issue_prompt) + strlen(cur_prompt) + 1;
+ char *new_prompt = realloc(issue_prompt, size);
- prompt_tmp = realloc(prompt_tmp, tot_size + 1);
- if (prompt_tmp == NULL) {
- prompt_tmp = prompt_tmp_tmp;
- retval = PAM_IGNORE;
- goto cleanup;
- }
+ if (new_prompt == NULL) {
+ pam_syslog(pamh, LOG_ERR, "out of memory");
+ retval = PAM_BUF_ERR;
+ goto out;
}
-
- 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));
- free(issue_file);
- return PAM_IGNORE;
+ issue_prompt = new_prompt;
}
- return retval;
+ strcat(issue_prompt, cur_prompt);
+ retval = pam_set_item(pamh, PAM_USER_PROMPT,
+ (const void *) issue_prompt);
+ out:
+ _pam_drop(issue_prompt);
+ return (retval == PAM_SUCCESS) ? PAM_IGNORE : retval;
}
PAM_EXTERN int
return PAM_IGNORE;
}
-static char *
-do_prompt (FILE *fd)
+static int
+read_issue_raw(pam_handle_t *pamh, FILE *fp, char **prompt)
+{
+ char *issue;
+ struct stat st;
+
+ *prompt = NULL;
+
+ if (fstat(fileno(fp), &st) < 0) {
+ pam_syslog(pamh, LOG_ERR, "stat error: %m");
+ return PAM_SERVICE_ERR;
+ }
+
+ if ((issue = malloc(st.st_size + 1)) == NULL) {
+ pam_syslog(pamh, LOG_ERR, "out of memory");
+ return PAM_BUF_ERR;
+ }
+
+ if (fread(issue, 1, st.st_size, fp) != st.st_size) {
+ pam_syslog(pamh, LOG_ERR, "read error: %m");
+ _pam_drop(issue);
+ return PAM_SERVICE_ERR;
+ }
+
+ issue[st.st_size] = '\0';
+ *prompt = issue;
+ return PAM_SUCCESS;
+}
+
+static int
+read_issue_quoted(pam_handle_t *pamh, FILE *fp, char **prompt)
{
int c;
size_t size = 1024;
char *issue;
- char buf[1024];
struct utsname uts;
- if (fd == NULL)
- return NULL;
+ *prompt = NULL;
- issue = (char *)malloc(size);
- if (issue == NULL)
- return NULL;
+ if ((issue = malloc(size)) == NULL) {
+ pam_syslog(pamh, LOG_ERR, "out of memory");
+ return PAM_BUF_ERR;
+ }
- issue[0] = '\0'; /* zero this, for strcat to work on first buf */
+ issue[0] = '\0';
(void) uname(&uts);
- while ((c = getc(fd)) != EOF) {
+ while ((c = getc(fp)) != EOF) {
+ char buf[1024];
+
+ buf[0] = '\0';
if (c == '\\') {
- c = getc(fd);
+ if ((c = getc(fp)) == EOF)
+ break;
switch (c) {
case 's':
- snprintf (buf, 1024, "%s", uts.sysname);
+ strncat(buf, uts.sysname, sizeof(buf) - 1);
break;
case 'n':
- snprintf (buf, 1024, "%s", uts.nodename);
+ strncat(buf, uts.nodename, sizeof(buf) - 1);
break;
case 'r':
- snprintf (buf, 1024, "%s", uts.release);
+ strncat(buf, uts.release, sizeof(buf) - 1);
break;
case 'v':
- snprintf (buf, 1024, "%s", uts.version);
+ strncat(buf, uts.version, sizeof(buf) - 1);
break;
case 'm':
- snprintf (buf, 1024, "%s", uts.machine);
+ strncat(buf, uts.machine, sizeof(buf) - 1);
break;
case 'o':
{
char domainname[256];
- if (getdomainname(domainname, sizeof(domainname)) == -1)
- domainname[0] = '\0';
- else
- domainname[sizeof(domainname)-1] = '\0';
- snprintf (buf, 1024, "%s", domainname);
+ if (getdomainname(domainname, sizeof(domainname)) >= 0) {
+ domainname[sizeof(domainname)-1] = '\0';
+ strncat(buf, domainname, sizeof(buf) - 1);
+ }
}
break;
-
case 'd':
case 't':
{
tm = localtime(&now);
if (c == 'd')
- snprintf (buf, 1024, "%s %s %d %d",
+ snprintf (buf, sizeof buf, "%s %s %d %d",
weekday[tm->tm_wday], month[tm->tm_mon],
- tm->tm_mday,
- tm->tm_year + 1900);
+ tm->tm_mday, tm->tm_year + 1900);
else
- snprintf (buf, 1024, "%02d:%02d:%02d",
+ snprintf (buf, sizeof buf, "%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);
+ if (ttyn) {
+ if (!strncmp(ttyn, "/dev/", 5))
+ ttyn += 5;
+ strncat(buf, ttyn, sizeof(buf) - 1);
+ }
}
break;
case 'u':
case 'U':
{
- int users = 0;
+ unsigned int users = 0;
struct utmp *ut;
setutent();
- while ((ut = getutent()))
+ while ((ut = getutent())) {
if (ut->ut_type == USER_PROCESS)
- users++;
+ ++users;
+ }
endutent();
if (c == 'U')
- snprintf (buf, 1024, "%d %s", users,
+ snprintf (buf, sizeof buf, "%u %s", users,
(users == 1) ? "user" : "users");
else
- snprintf (buf, 1024, "%d", users);
+ snprintf (buf, sizeof buf, "%u", 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;
- }
+ }
+
+ if ((strlen(issue) + strlen(buf)) + 1 > size) {
+ char *new_issue;
+
+ size += strlen(buf) + 1;
+ new_issue = (char *) realloc (issue, size);
+ if (new_issue == NULL) {
+ _pam_drop(issue);
+ return PAM_BUF_ERR;
}
+ issue = new_issue;
strcat(issue, buf);
}
}
- return issue;
+ if (ferror(fp)) {
+ pam_syslog(pamh, LOG_ERR, "read error: %m");
+ _pam_drop(issue);
+ return PAM_SERVICE_ERR;
+ }
+
+ *prompt = issue;
+ return PAM_SUCCESS;
}
#ifdef PAM_STATIC
projects / linux-pam / commitdiff