source: auth_pam.c @ 16ea00d

#define BITLBEE_CORE
#include "bitlbee.h"
#include <security/pam_appl.h>

#define PAM_CHECK(x) do { \
        ret = (x); \
        if(ret != PAM_SUCCESS) { \
                pam_func = #x; \
                goto pam_error; \
        } \
} while(0)

/* This function fills in the password when PAM asks for it */
int pamconv(int num_msg, const struct pam_message **msg, struct pam_response **resp, void *appdata_ptr) {
        int i;
        struct pam_response *rsp = g_new0(struct pam_response, num_msg);

        for (i = 0; i < num_msg; i++) {
                rsp[i].resp = NULL;
                rsp[i].resp_retcode = 0;
                if (msg[i]->msg_style == PAM_PROMPT_ECHO_OFF) {
                        rsp[i].resp = g_strdup((char *)appdata_ptr);
                }
        }
        *resp = rsp;
        return PAM_SUCCESS;
}

static storage_status_t pam_check_pass(const char *nick, const char *password)
{
        int ret;
        const struct pam_conv pamc = { pamconv, (void*) password };
        pam_handle_t *pamh = NULL;
        char *pam_func;

        PAM_CHECK(pam_start("bitlbee", nick, &pamc, &pamh));
        PAM_CHECK(pam_authenticate(pamh, PAM_DISALLOW_NULL_AUTHTOK));
        PAM_CHECK(pam_acct_mgmt(pamh, 0));

        pam_end(pamh, ret);
        return STORAGE_OK;

pam_error:
        switch (ret) {
                case PAM_AUTH_ERR:
                        pam_end(pamh, ret);
                        return STORAGE_INVALID_PASSWORD;
                case PAM_USER_UNKNOWN:
                case PAM_PERM_DENIED:
                        pam_end(pamh, ret);
                        return STORAGE_NO_SUCH_USER;
                default:
                        log_message(LOGLVL_WARNING, "%s failed: %s", pam_func, pam_strerror(pamh, ret));
                        pam_end(pamh, ret);
                        return STORAGE_OTHER_ERROR;
        }
}

auth_backend_t auth_pam = {
        .name = "pam",
        .check_pass = pam_check_pass,
};