int
my_conv(int n, const struct pam_message **msg,
struct pam_response **resp, void *data)
{
struct pam_response *aresp;
char buf[PAM_MAX_RESP_SIZE];
const char *p;
int i;
if (n <= 0 || n > PAM_MAX_NUM_MSG)
return (PAM_CONV_ERR);
if ((aresp = calloc(n, sizeof *aresp)) == NULL)
return (PAM_BUF_ERR);
for (i = 0; i < n; ++i) {
aresp[i].resp_retcode = 0;
aresp[i].resp = NULL;
p = PAM_MSG_MEMBER(msg, i, msg);
switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
case PAM_PROMPT_ECHO_OFF:
aresp[i].resp = strdup(getpass(p));
if (aresp[i].resp == NULL)
goto fail;
break;
case PAM_PROMPT_ECHO_ON:
fputs(p, stderr);
if (fgets(buf, sizeof(buf), stdin) == NULL)
goto fail;
aresp[i].resp = strdup(buf);
if (aresp[i].resp == NULL)
goto fail;
break;
case PAM_ERROR_MSG:
fputs(p, stderr);
if (strlen(p) > 0 && p[strlen(p) - 1] != '\n')
fputc('\n', stderr);
break;
case PAM_TEXT_INFO:
fputs(p, stdout);
if (strlen(p) > 0 && p[strlen(p) - 1] != '\n')
fputc('\n', stdout);
break;
default:
goto fail;
}
}
*resp = aresp;
return (PAM_SUCCESS);
fail:
for (i = 0; i < n; ++i) {
if (aresp[i].resp != NULL)
free(aresp[i].resp);
}
*resp = NULL;
return (PAM_CONV_ERR);
}
static int
sshpam_tty_conv(int n, sshpam_const struct pam_message **msg,
struct pam_response **resp, void *data)
{
char input[PAM_MAX_MSG_SIZE];
struct pam_response *reply;
int i;
debug3("PAM: %s called with %d messages", __func__, n);
*resp = NULL;
if (n <= 0 || n > PAM_MAX_NUM_MSG || !isatty(STDIN_FILENO))
return (PAM_CONV_ERR);
if ((reply = calloc(n, sizeof(*reply))) == NULL)
return (PAM_CONV_ERR);
for (i = 0; i < n; ++i) {
switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
case PAM_PROMPT_ECHO_OFF:
reply[i].resp =
read_passphrase(PAM_MSG_MEMBER(msg, i, msg),
RP_ALLOW_STDIN);
reply[i].resp_retcode = PAM_SUCCESS;
break;
case PAM_PROMPT_ECHO_ON:
fprintf(stderr, "%s\n", PAM_MSG_MEMBER(msg, i, msg));
if (fgets(input, sizeof input, stdin) == NULL)
input[0] = '\0';
if ((reply[i].resp = strdup(input)) == NULL)
goto fail;
reply[i].resp_retcode = PAM_SUCCESS;
break;
case PAM_ERROR_MSG:
case PAM_TEXT_INFO:
fprintf(stderr, "%s\n", PAM_MSG_MEMBER(msg, i, msg));
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);
}
/*
* "Blind" conversation function for password authentication. Assumes that
* echo-off prompts are for the password and stores messages for later
* display.
*/
static int
sshpam_passwd_conv(int n, sshpam_const 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 = calloc(n, sizeof(*reply))) == NULL)
return (PAM_CONV_ERR);
for (i = 0; i < n; ++i) {
switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
case PAM_PROMPT_ECHO_OFF:
if (sshpam_password == NULL)
goto fail;
if ((reply[i].resp = strdup(sshpam_password)) == NULL)
goto fail;
reply[i].resp_retcode = PAM_SUCCESS;
break;
case PAM_ERROR_MSG:
case PAM_TEXT_INFO:
len = strlen(PAM_MSG_MEMBER(msg, i, msg));
if (len > 0) {
buffer_append(&loginmsg,
PAM_MSG_MEMBER(msg, i, msg), len);
buffer_append(&loginmsg, "\n", 1);
}
if ((reply[i].resp = strdup("")) == NULL)
goto fail;
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);
}
/*
* PAM conversation function for non-interactive userauth methods that
* really cannot do any prompting. Password userauth and CHANGEREQ can
* always set the PAM_AUTHTOK and PAM_OLDAUTHTOK items to avoid
* conversation (and if they do and nonetheless some module tries to
* converse, then password userauth / CHANGEREQ MUST fail).
*
* Except, PAM_TEXT_INFO and PAM_ERROR_MSG prompts can be squirelled
* away and shown to the user later.
*
* Keyboard-interactive userauth has its own much more interesting
* conversation function.
*
*/
static int
do_pam_conversation(int num_msg, const struct pam_message **msg,
struct pam_response **resp, void *appdata_ptr)
{
struct pam_response *reply;
int count;
/* PAM will free this later */
reply = xmalloc(num_msg * sizeof(*reply));
(void) memset(reply, 0, num_msg * sizeof(*reply));
for (count = 0; count < num_msg; count++) {
/*
* We can't use stdio yet, queue messages for
* printing later
*/
switch(PAM_MSG_MEMBER(msg, count, msg_style)) {
case PAM_PROMPT_ECHO_ON:
xfree(reply);
return PAM_CONV_ERR;
case PAM_PROMPT_ECHO_OFF:
xfree(reply);
return PAM_CONV_ERR;
break;
case PAM_ERROR_MSG:
case PAM_TEXT_INFO:
if (PAM_MSG_MEMBER(msg, count, msg) != NULL) {
message_cat(&__pam_msg,
PAM_MSG_MEMBER(msg, count, msg));
}
reply[count].resp = xstrdup("");
reply[count].resp_retcode = PAM_SUCCESS;
break;
default:
xfree(reply);
return PAM_CONV_ERR;
}
}
*resp = reply;
return PAM_SUCCESS;
}
static int
sshpam_store_conv(int n, sshpam_const struct pam_message **msg,
struct pam_response **resp, void *data)
{
struct pam_response *reply;
int r, i;
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 = calloc(n, sizeof(*reply))) == NULL)
return (PAM_CONV_ERR);
for (i = 0; i < n; ++i) {
switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
case PAM_ERROR_MSG:
case PAM_TEXT_INFO:
if ((r = sshbuf_putf(loginmsg, "%s\n",
PAM_MSG_MEMBER(msg, i, msg))) != 0)
fatal("%s: buffer error: %s",
__func__, ssh_err(r));
reply[i].resp_retcode = PAM_SUCCESS;
break;
default:
goto fail;
}
}
*resp = reply;
return (PAM_SUCCESS);
fail:
for(i = 0; i < n; i++) {
free(reply[i].resp);
}
free(reply);
return (PAM_CONV_ERR);
}
/*
* Conversation function for authentication thread.
*/
static int
sshpam_thread_conv(int n, sshpam_const struct pam_message **msg,
struct pam_response **resp, void *data)
{
Buffer buffer;
struct pam_ctxt *ctxt;
struct pam_response *reply;
int i;
debug3("PAM: %s entering, %d messages", __func__, n);
*resp = NULL;
if (data == NULL) {
error("PAM: conversation function passed a null context");
return (PAM_CONV_ERR);
}
ctxt = data;
if (n <= 0 || n > PAM_MAX_NUM_MSG)
return (PAM_CONV_ERR);
if ((reply = calloc(n, sizeof(*reply))) == NULL)
return (PAM_CONV_ERR);
buffer_init(&buffer);
for (i = 0; i < n; ++i) {
switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
case PAM_PROMPT_ECHO_OFF:
buffer_put_cstring(&buffer,
PAM_MSG_MEMBER(msg, i, msg));
if (ssh_msg_send(ctxt->pam_csock,
PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1)
goto fail;
if (ssh_msg_recv(ctxt->pam_csock, &buffer) == -1)
goto fail;
if (buffer_get_char(&buffer) != PAM_AUTHTOK)
goto fail;
reply[i].resp = buffer_get_string(&buffer, NULL);
break;
case PAM_PROMPT_ECHO_ON:
buffer_put_cstring(&buffer,
PAM_MSG_MEMBER(msg, i, msg));
if (ssh_msg_send(ctxt->pam_csock,
PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1)
goto fail;
if (ssh_msg_recv(ctxt->pam_csock, &buffer) == -1)
goto fail;
if (buffer_get_char(&buffer) != PAM_AUTHTOK)
goto fail;
reply[i].resp = buffer_get_string(&buffer, NULL);
break;
case PAM_ERROR_MSG:
buffer_put_cstring(&buffer,
PAM_MSG_MEMBER(msg, i, msg));
if (ssh_msg_send(ctxt->pam_csock,
PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1)
goto fail;
break;
case PAM_TEXT_INFO:
buffer_put_cstring(&buffer,
PAM_MSG_MEMBER(msg, i, msg));
if (ssh_msg_send(ctxt->pam_csock,
PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1)
goto fail;
break;
default:
goto fail;
}
buffer_clear(&buffer);
}
buffer_free(&buffer);
*resp = reply;
return (PAM_SUCCESS);
fail:
for(i = 0; i < n; i++) {
free(reply[i].resp);
}
free(reply);
buffer_free(&buffer);
return (PAM_CONV_ERR);
}
static int
do_pam_conversation_kbd_int(int num_msg, const struct pam_message **msg,
struct pam_response **resp, void *appdata_ptr)
{
int i, j, done;
char *text;
context_pam2.finished = 0;
context_pam2.num_received = 0;
context_pam2.num_expected = 0;
context_pam2.prompts = xmalloc(sizeof(int) * num_msg);
context_pam2.responses = xmalloc(sizeof(struct pam_response) * num_msg);
memset(context_pam2.responses, 0, sizeof(struct pam_response) * num_msg);
text = NULL;
for (i = 0, context_pam2.num_expected = 0; i < num_msg; i++) {
int style = PAM_MSG_MEMBER(msg, i, msg_style);
switch (style) {
case PAM_PROMPT_ECHO_ON:
case PAM_PROMPT_ECHO_OFF:
context_pam2.num_expected++;
break;
case PAM_TEXT_INFO:
case PAM_ERROR_MSG:
default:
/* Capture all these messages to be sent at once */
message_cat(&text, PAM_MSG_MEMBER(msg, i, msg));
break;
}
}
if (context_pam2.num_expected == 0)
return PAM_SUCCESS;
packet_start(SSH2_MSG_USERAUTH_INFO_REQUEST);
packet_put_cstring(""); /* Name */
packet_put_cstring(""); /* Instructions */
packet_put_cstring(""); /* Language */
packet_put_int(context_pam2.num_expected);
for (i = 0, j = 0; i < num_msg; i++) {
int style = PAM_MSG_MEMBER(msg, i, msg_style);
/* Skip messages which don't need a reply */
if (style != PAM_PROMPT_ECHO_ON && style != PAM_PROMPT_ECHO_OFF)
continue;
context_pam2.prompts[j++] = i;
if (text) {
message_cat(&text, PAM_MSG_MEMBER(msg, i, msg));
packet_put_cstring(text);
text = NULL;
} else
packet_put_cstring(PAM_MSG_MEMBER(msg, i, msg));
packet_put_char(style == PAM_PROMPT_ECHO_ON);
}
packet_send();
packet_write_wait();
/*
* Grabbing control of execution and spinning until we get what
* we want is probably rude, but it seems to work properly, and
* the client *should* be in lock-step with us, so the loop should
* only be traversed once.
*/
while(context_pam2.finished == 0) {
done = 1;
dispatch_run(DISPATCH_BLOCK, &done, appdata_ptr);
if(context_pam2.finished == 0)
debug("extra packet during conversation");
}
if(context_pam2.num_received == context_pam2.num_expected) {
*resp = context_pam2.responses;
return PAM_SUCCESS;
} else
return PAM_CONV_ERR;
}
/*
* Conversation function for authentication thread.
*/
static int
sshpam_thread_conv(int n, sshpam_const struct pam_message **msg,
struct pam_response **resp, void *data)
{
struct sshbuf *buffer;
struct pam_ctxt *ctxt;
struct pam_response *reply;
int r, i;
u_char status;
debug3("PAM: %s entering, %d messages", __func__, n);
*resp = NULL;
if (data == NULL) {
error("PAM: conversation function passed a null context");
return (PAM_CONV_ERR);
}
ctxt = data;
if (n <= 0 || n > PAM_MAX_NUM_MSG)
return (PAM_CONV_ERR);
if ((reply = calloc(n, sizeof(*reply))) == NULL)
return PAM_CONV_ERR;
if ((buffer = sshbuf_new()) == NULL) {
free(reply);
return PAM_CONV_ERR;
}
for (i = 0; i < n; ++i) {
switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
case PAM_PROMPT_ECHO_OFF:
case PAM_PROMPT_ECHO_ON:
if ((r = sshbuf_put_cstring(buffer,
PAM_MSG_MEMBER(msg, i, msg))) != 0)
fatal("%s: buffer error: %s",
__func__, ssh_err(r));
if (ssh_msg_send(ctxt->pam_csock,
PAM_MSG_MEMBER(msg, i, msg_style), buffer) == -1)
goto fail;
if (ssh_msg_recv(ctxt->pam_csock, buffer) == -1)
goto fail;
if ((r = sshbuf_get_u8(buffer, &status)) != 0)
fatal("%s: buffer error: %s",
__func__, ssh_err(r));
if (status != PAM_AUTHTOK)
goto fail;
if ((r = sshbuf_get_cstring(buffer,
&reply[i].resp, NULL)) != 0)
fatal("%s: buffer error: %s",
__func__, ssh_err(r));
break;
case PAM_ERROR_MSG:
case PAM_TEXT_INFO:
if ((r = sshbuf_put_cstring(buffer,
PAM_MSG_MEMBER(msg, i, msg))) != 0)
fatal("%s: buffer error: %s",
__func__, ssh_err(r));
if (ssh_msg_send(ctxt->pam_csock,
PAM_MSG_MEMBER(msg, i, msg_style), buffer) == -1)
goto fail;
break;
default:
goto fail;
}
sshbuf_reset(buffer);
}
sshbuf_free(buffer);
*resp = reply;
return (PAM_SUCCESS);
fail:
for(i = 0; i < n; i++) {
free(reply[i].resp);
}
free(reply);
sshbuf_free(buffer);
return (PAM_CONV_ERR);
}
