extern int compat20;
extern u_int utmp_len;
+/* so we don't silently change behaviour */
#ifdef USE_POSIX_THREADS
+# error "USE_POSIX_THREADS replaced by UNSUPPORTED_POSIX_THREADS_HACK"
+#endif
+
+/*
+ * Formerly known as USE_POSIX_THREADS, using this is completely unsupported
+ * and generally a bad idea. Use at own risk and do not expect support if
+ * this breaks.
+ */
+#ifdef UNSUPPORTED_POSIX_THREADS_HACK
#include <pthread.h>
/*
* Avoid namespace clash when *not* using pthreads for systems *with*
static void sshpam_free_ctx(void *);
static struct pam_ctxt *cleanup_ctxt;
-#ifndef USE_POSIX_THREADS
+#ifndef UNSUPPORTED_POSIX_THREADS_HACK
/*
* Simulate threads with processes.
*/
if (cleanup_ctxt == NULL)
return; /* handler called after PAM cleanup, shouldn't happen */
if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, WNOHANG)
- == -1) {
+ <= 0) {
/* PAM thread has not exitted, privsep slave must have */
kill(cleanup_ctxt->pam_thread, SIGTERM);
if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, 0)
- == -1)
+ <= 0)
return; /* could not wait */
}
if (WIFSIGNALED(sshpam_thread_status) &&
static char **sshpam_env = NULL;
static Authctxt *sshpam_authctxt = NULL;
static const char *sshpam_password = NULL;
+static char badpw[] = "\b\n\r\177INCORRECT";
/* Some PAM implementations don't implement this */
#ifndef HAVE_PAM_GETENVLIST
}
#endif
+/*
+ * Some platforms, notably Solaris, do not enforce password complexity
+ * rules during pam_chauthtok() if the real uid of the calling process
+ * is 0, on the assumption that it's being called by "passwd" run by root.
+ * This wraps pam_chauthtok and sets/restore the real uid so PAM will do
+ * the right thing.
+ */
+#ifdef SSHPAM_CHAUTHTOK_NEEDS_RUID
+static int
+sshpam_chauthtok_ruid(pam_handle_t *pamh, int flags)
+{
+ int result;
+
+ if (sshpam_authctxt == NULL)
+ fatal("PAM: sshpam_authctxt not initialized");
+ if (setreuid(sshpam_authctxt->pw->pw_uid, -1) == -1)
+ fatal("%s: setreuid failed: %s", __func__, strerror(errno));
+ result = pam_chauthtok(pamh, flags);
+ if (setreuid(0, -1) == -1)
+ fatal("%s: setreuid failed: %s", __func__, strerror(errno));
+ return result;
+}
+# define pam_chauthtok(a,b) (sshpam_chauthtok_ruid((a), (b)))
+#endif
+
void
sshpam_password_change_required(int reqd)
{
debug3("PAM: %s entering", __func__);
-#ifndef USE_POSIX_THREADS
+#ifndef UNSUPPORTED_POSIX_THREADS_HACK
/* Import variables set by do_pam_account */
sshpam_account_status = buffer_get_int(b);
sshpam_password_change_required(buffer_get_int(b));
struct pam_ctxt *ctxt = ctxtp;
Buffer buffer;
struct pam_conv sshpam_conv;
-#ifndef USE_POSIX_THREADS
+ int flags = (options.permit_empty_passwd == 0 ?
+ PAM_DISALLOW_NULL_AUTHTOK : 0);
+#ifndef UNSUPPORTED_POSIX_THREADS_HACK
extern char **environ;
char **env_from_pam;
u_int i;
const char *pam_user;
pam_get_item(sshpam_handle, PAM_USER, (void **)&pam_user);
- setproctitle("%s [pam]", pam_user);
environ[0] = NULL;
+
+ if (sshpam_authctxt != NULL) {
+ setproctitle("%s [pam]",
+ sshpam_authctxt->valid ? pam_user : "unknown");
+ }
#endif
sshpam_conv.conv = sshpam_thread_conv;
(const void *)&sshpam_conv);
if (sshpam_err != PAM_SUCCESS)
goto auth_fail;
- sshpam_err = pam_authenticate(sshpam_handle, 0);
+ sshpam_err = pam_authenticate(sshpam_handle, flags);
if (sshpam_err != PAM_SUCCESS)
goto auth_fail;
buffer_put_cstring(&buffer, "OK");
-#ifndef USE_POSIX_THREADS
+#ifndef UNSUPPORTED_POSIX_THREADS_HACK
/* Export variables set by do_pam_account */
buffer_put_int(&buffer, sshpam_account_status);
buffer_put_int(&buffer, sshpam_authctxt->force_pwchange);
buffer_put_int(&buffer, i);
for(i = 0; env_from_pam != NULL && env_from_pam[i] != NULL; i++)
buffer_put_cstring(&buffer, env_from_pam[i]);
-#endif /* USE_POSIX_THREADS */
+#endif /* UNSUPPORTED_POSIX_THREADS_HACK */
/* XXX - can't do much about an error here */
ssh_msg_send(ctxt->pam_csock, sshpam_err, &buffer);
static struct pam_conv null_conv = { sshpam_null_conv, NULL };
+static int
+sshpam_store_conv(int n, struct pam_message **msg,
+ struct pam_response **resp, void *data)
+{
+ struct pam_response *reply;
+ int i;
+ size_t len;
+
+ debug3("PAM: %s called with %d messages", __func__, n);
+ *resp = NULL;
+
+ if (n <= 0 || n > PAM_MAX_NUM_MSG)
+ return (PAM_CONV_ERR);
+
+ if ((reply = malloc(n * sizeof(*reply))) == NULL)
+ return (PAM_CONV_ERR);
+ memset(reply, 0, n * sizeof(*reply));
+
+ for (i = 0; i < n; ++i) {
+ switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
+ case PAM_ERROR_MSG:
+ case PAM_TEXT_INFO:
+ len = strlen(PAM_MSG_MEMBER(msg, i, msg));
+ buffer_append(&loginmsg, PAM_MSG_MEMBER(msg, i, msg), len);
+ buffer_append(&loginmsg, "\n", 1 );
+ reply[i].resp_retcode = PAM_SUCCESS;
+ break;
+ default:
+ goto fail;
+ }
+ }
+ *resp = reply;
+ return (PAM_SUCCESS);
+
+ fail:
+ for(i = 0; i < n; i++) {
+ if (reply[i].resp != NULL)
+ xfree(reply[i].resp);
+ }
+ xfree(reply);
+ return (PAM_CONV_ERR);
+}
+
+static struct pam_conv store_conv = { sshpam_store_conv, NULL };
+
void
sshpam_cleanup(void)
{
}
debug("PAM: initializing for \"%s\"", user);
sshpam_err =
- pam_start(SSHD_PAM_SERVICE, user, &null_conv, &sshpam_handle);
+ pam_start(SSHD_PAM_SERVICE, user, &store_conv, &sshpam_handle);
sshpam_authctxt = authctxt;
if (sshpam_err != PAM_SUCCESS) {
size_t plen;
u_char type;
char *msg;
- size_t len;
+ size_t len, mlen;
debug3("PAM: %s entering", __func__);
buffer_init(&buffer);
while (ssh_msg_recv(ctxt->pam_psock, &buffer) == 0) {
type = buffer_get_char(&buffer);
msg = buffer_get_string(&buffer, NULL);
+ mlen = strlen(msg);
switch (type) {
case PAM_PROMPT_ECHO_ON:
case PAM_PROMPT_ECHO_OFF:
*num = 1;
- len = plen + strlen(msg) + 1;
+ len = plen + mlen + 1;
**prompts = xrealloc(**prompts, len);
- plen += snprintf(**prompts + plen, len, "%s", msg);
+ strlcpy(**prompts + plen, msg, len - plen);
+ plen += mlen;
**echo_on = (type == PAM_PROMPT_ECHO_ON);
xfree(msg);
return (0);
case PAM_ERROR_MSG:
case PAM_TEXT_INFO:
/* accumulate messages */
- len = plen + strlen(msg) + 2;
+ len = plen + mlen + 2;
**prompts = xrealloc(**prompts, len);
- plen += snprintf(**prompts + plen, len, "%s\n", msg);
+ strlcpy(**prompts + plen, msg, len - plen);
+ plen += mlen;
+ strlcat(**prompts + plen, "\n", len - plen);
+ plen++;
xfree(msg);
break;
case PAM_SUCCESS:
**prompts = NULL;
}
if (type == PAM_SUCCESS) {
+ if (!sshpam_authctxt->valid ||
+ (sshpam_authctxt->pw->pw_uid == 0 &&
+ options.permit_root_login != PERMIT_YES))
+ fatal("Internal error: PAM auth "
+ "succeeded when it should have "
+ "failed");
import_environments(&buffer);
*num = 0;
**echo_on = 0;
return (-1);
}
buffer_init(&buffer);
- buffer_put_cstring(&buffer, *resp);
+ if (sshpam_authctxt->valid &&
+ (sshpam_authctxt->pw->pw_uid != 0 ||
+ options.permit_root_login == PERMIT_YES))
+ buffer_put_cstring(&buffer, *resp);
+ else
+ buffer_put_cstring(&buffer, badpw);
if (ssh_msg_send(ctxt->pam_psock, PAM_AUTHTOK, &buffer) == -1) {
buffer_free(&buffer);
return (-1);
u_int
do_pam_account(void)
{
+ debug("%s: called", __func__);
if (sshpam_account_status != -1)
return (sshpam_account_status);
sshpam_err = pam_acct_mgmt(sshpam_handle, 0);
- debug3("PAM: %s pam_acct_mgmt = %d", __func__, sshpam_err);
+ debug3("PAM: %s pam_acct_mgmt = %d (%s)", __func__, sshpam_err,
+ pam_strerror(sshpam_handle, sshpam_err));
if (sshpam_err != PAM_SUCCESS && sshpam_err != PAM_NEW_AUTHTOK_REQD) {
sshpam_account_status = 0;
do_pam_setcred(int init)
{
sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
- (const void *)&null_conv);
+ (const void *)&store_conv);
if (sshpam_err != PAM_SUCCESS)
fatal("PAM: failed to set PAM_CONV: %s",
pam_strerror(sshpam_handle, sshpam_err));
case PAM_PROMPT_ECHO_ON:
fprintf(stderr, "%s\n", PAM_MSG_MEMBER(msg, i, msg));
fgets(input, sizeof input, stdin);
- reply[i].resp = xstrdup(input);
+ if ((reply[i].resp = strdup(input)) == NULL)
+ goto fail;
reply[i].resp_retcode = PAM_SUCCESS;
break;
case PAM_ERROR_MSG:
pam_strerror(sshpam_handle, sshpam_err));
}
-static int
-sshpam_store_conv(int n, struct pam_message **msg,
- struct pam_response **resp, void *data)
-{
- struct pam_response *reply;
- int i;
- size_t len;
-
- debug3("PAM: %s called with %d messages", __func__, n);
- *resp = NULL;
-
- if (n <= 0 || n > PAM_MAX_NUM_MSG)
- return (PAM_CONV_ERR);
-
- if ((reply = malloc(n * sizeof(*reply))) == NULL)
- return (PAM_CONV_ERR);
- memset(reply, 0, n * sizeof(*reply));
-
- for (i = 0; i < n; ++i) {
- switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
- case PAM_ERROR_MSG:
- case PAM_TEXT_INFO:
- len = strlen(PAM_MSG_MEMBER(msg, i, msg));
- buffer_append(&loginmsg, PAM_MSG_MEMBER(msg, i, msg), len);
- buffer_append(&loginmsg, "\n", 1 );
- reply[i].resp_retcode = PAM_SUCCESS;
- break;
- default:
- goto fail;
- }
- }
- *resp = reply;
- return (PAM_SUCCESS);
-
- fail:
- for(i = 0; i < n; i++) {
- if (reply[i].resp != NULL)
- xfree(reply[i].resp);
- }
- xfree(reply);
- return (PAM_CONV_ERR);
-}
-
-static struct pam_conv store_conv = { sshpam_store_conv, NULL };
-
void
do_pam_session(void)
{
fatal("PAM: failed to set PAM_CONV: %s",
pam_strerror(sshpam_handle, sshpam_err));
sshpam_err = pam_open_session(sshpam_handle, 0);
- if (sshpam_err != PAM_SUCCESS)
- fatal("PAM: pam_open_session(): %s",
+ if (sshpam_err == PAM_SUCCESS)
+ sshpam_session_open = 1;
+ else {
+ sshpam_session_open = 0;
+ disable_forwarding();
+ error("PAM: pam_open_session(): %s",
pam_strerror(sshpam_handle, sshpam_err));
- sshpam_session_open = 1;
+ }
+
+}
+
+int
+is_pam_session_open(void)
+{
+ return sshpam_session_open;
}
/*
case PAM_PROMPT_ECHO_OFF:
if (sshpam_password == NULL)
goto fail;
- reply[i].resp = xstrdup(sshpam_password);
+ if ((reply[i].resp = strdup(sshpam_password)) == NULL)
+ goto fail;
reply[i].resp_retcode = PAM_SUCCESS;
break;
case PAM_ERROR_MSG:
PAM_MSG_MEMBER(msg, i, msg), len);
buffer_append(&loginmsg, "\n", 1);
}
- reply[i].resp = xstrdup("");
+ if ((reply[i].resp = strdup("")) == NULL)
+ goto fail;
reply[i].resp_retcode = PAM_SUCCESS;
break;
default:
{
int flags = (options.permit_empty_passwd == 0 ?
PAM_DISALLOW_NULL_AUTHTOK : 0);
- static char badpw[] = "\b\n\r\177INCORRECT";
if (!options.use_pam || sshpam_handle == NULL)
fatal("PAM: %s called when PAM disabled or failed to "