diff options
Diffstat (limited to 'modules/pam_echo/pam_echo.c')
| -rw-r--r-- | modules/pam_echo/pam_echo.c | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/modules/pam_echo/pam_echo.c b/modules/pam_echo/pam_echo.c new file mode 100644 index 0000000..181aeb4 --- /dev/null +++ b/modules/pam_echo/pam_echo.c @@ -0,0 +1,260 @@ +/* + * Copyright (c) 2005, 2006 Thorsten Kukuk <kukuk@suse.de> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, and the entire permission notice in its entirety, + * including the disclaimer of warranties. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote + * products derived from this software without specific prior + * written permission. + * + * ALTERNATIVELY, this product may be distributed under the terms of + * the GNU Public License, in which case the provisions of the GPL are + * required INSTEAD OF the above restrictions. (This clause is + * necessary due to a potential bad interaction between the GPL and + * the restrictions contained in a BSD-style copyright.) + * + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, + * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED + * OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#if defined(HAVE_CONFIG_H) +#include "config.h" +#endif + +#include <errno.h> +#include <stdio.h> +#include <fcntl.h> +#include <string.h> +#include <stdlib.h> +#include <unistd.h> +#include <limits.h> +#include <syslog.h> +#include <sys/types.h> +#include <sys/stat.h> + +#ifndef HOST_NAME_MAX +#define HOST_NAME_MAX 255 +#endif + +#include <security/pam_modules.h> +#include <security/pam_modutil.h> +#include <security/_pam_macros.h> +#include <security/pam_ext.h> +#include "pam_inline.h" + +static int +replace_and_print (pam_handle_t *pamh, const char *mesg) +{ + char *output; + size_t length = strlen (mesg) + PAM_MAX_MSG_SIZE; + char myhostname[HOST_NAME_MAX+1]; + const void *str = NULL; + const char *p, *q; + int item; + size_t len; + + output = malloc (length); + if (output == NULL) + { + pam_syslog (pamh, LOG_CRIT, "running out of memory"); + return PAM_BUF_ERR; + } + + for (p = mesg, len = 0; *p != '\0' && len < length - 1; ++p) + { + if (*p != '%' || p[1] == '\0') + { + output[len++] = *p; + continue; + } + switch (*++p) + { + case 'H': + item = PAM_RHOST; + break; + case 'h': + item = -2; /* aka PAM_LOCALHOST */ + break; + case 's': + item = PAM_SERVICE; + break; + case 't': + item = PAM_TTY; + break; + case 'U': + item = PAM_RUSER; + break; + case 'u': + item = PAM_USER; + break; + default: + output[len++] = *p; + continue; + } + if (item == -2) + { + if (gethostname (myhostname, sizeof (myhostname)) == -1) + str = NULL; + else + str = &myhostname; + } + else + { + if (pam_get_item (pamh, item, &str) != PAM_SUCCESS) + str = NULL; + } + if (str == NULL) + str = "(null)"; + for (q = str; *q != '\0' && len < length - 1; ++q) + output[len++] = *q; + } + output[len] = '\0'; + + pam_info (pamh, "%s", output); + free (output); + + return PAM_SUCCESS; +} + +static int +pam_echo (pam_handle_t *pamh, int flags, int argc, const char **argv) +{ + int fd; + int orig_argc = argc; + const char **orig_argv = argv; + const char *file = NULL; + int retval; + + if (flags & PAM_SILENT) + return PAM_IGNORE; + + for (; argc-- > 0; ++argv) + { + const char *str = pam_str_skip_prefix(*argv, "file="); + if (str != NULL) + file = str; + } + + /* No file= option, use argument for output. */ + if (file == NULL || file[0] == '\0') + { + char msg[PAM_MAX_MSG_SIZE]; + const char *p; + int i; + size_t len; + + for (i = 0, len = 0; i < orig_argc && len < sizeof (msg) - 1; ++i) + { + if (i > 0) + msg[len++] = ' '; + for (p = orig_argv[i]; *p != '\0' && len < sizeof(msg) - 1; ++p) + msg[len++] = *p; + } + msg[len] = '\0'; + + retval = replace_and_print (pamh, msg); + } + else if ((fd = open (file, O_RDONLY, 0)) >= 0) + { + char *mtmp = NULL; + struct stat st; + + /* load file into message buffer. */ + if ((fstat (fd, &st) < 0) || !st.st_size) + { + close (fd); + return PAM_IGNORE; + } + + mtmp = malloc (st.st_size + 1); + if (!mtmp) + { + close (fd); + return PAM_BUF_ERR; + } + + if (pam_modutil_read (fd, mtmp, st.st_size) == -1) + { + pam_syslog (pamh, LOG_ERR, "Error while reading %s: %m", file); + free (mtmp); + close (fd); + return PAM_IGNORE; + } + + if (mtmp[st.st_size - 1] == '\n') + mtmp[st.st_size - 1] = '\0'; + else + mtmp[st.st_size] = '\0'; + + close (fd); + retval = replace_and_print (pamh, mtmp); + free (mtmp); + } + else + { + pam_syslog (pamh, LOG_ERR, "Cannot open %s: %m", file); + retval = PAM_IGNORE; + } + return retval; +} + +int +pam_sm_authenticate (pam_handle_t *pamh, int flags, int argc, + const char **argv) +{ + return pam_echo (pamh, flags, argc, argv); +} + +int +pam_sm_setcred (pam_handle_t *pamh UNUSED, int flags UNUSED, + int argc UNUSED, const char **argv UNUSED) +{ + return PAM_IGNORE; +} + +int +pam_sm_acct_mgmt (pam_handle_t *pamh, int flags, int argc, + const char **argv) +{ + return pam_echo (pamh, flags, argc, argv); +} + +int +pam_sm_open_session (pam_handle_t *pamh, int flags, int argc, + const char **argv) +{ + return pam_echo (pamh, flags, argc, argv); +} + +int +pam_sm_close_session (pam_handle_t *pamh UNUSED, int flags UNUSED, + int argc UNUSED, const char **argv UNUSED) +{ + return PAM_IGNORE; +} + +int +pam_sm_chauthtok (pam_handle_t *pamh, int flags, int argc, + const char **argv) +{ + if (flags & PAM_PRELIM_CHECK) + return pam_echo (pamh, flags, argc, argv); + else + return PAM_IGNORE; +} |