Initial revision

1 files changed, 504 insertions, 0 deletions

diff --git a/modules/pam_mail/pam_mail.c b/modules/pam_mail/pam_mail.c
new file mode 100644
index 00000000..f67b6f02
--- /dev/null
+++ b/modules/pam_mail/pam_mail.c
@@ -0,0 +1,504 @@
+/* pam_mail module */
+
+/*
+ * $Id$
+ *
+ * Written by Andrew Morgan <morgan@linux.kernel.org> 1996/3/11
+ * $HOME additions by David Kinchlea <kinch@kinch.ark.com> 1997/1/7
+ * mailhash additions by Chris Adams <cadams@ro.com> 1998/7/11
+ */
+
+#define DEFAULT_MAIL_DIRECTORY    "/var/spool/mail"
+#define MAIL_FILE_FORMAT          "%s%s/%s"
+#define MAIL_ENV_NAME             "MAIL"
+#define MAIL_ENV_FORMAT           MAIL_ENV_NAME "=%s"
+#define YOUR_MAIL_VERBOSE_FORMAT  "You have %s mail in %s."
+#define YOUR_MAIL_STANDARD_FORMAT "You have %smail."
+#define NO_MAIL_STANDARD_FORMAT   "No mail." 
+
+#define _BSD_SOURCE
+
+#ifdef linux
+# define _GNU_SOURCE
+# include <features.h>
+#endif
+
+#include <ctype.h>
+#include <pwd.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <syslog.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <dirent.h>
+
+#ifdef WANT_PWDB
+#include <pwdb/pwdb_public.h>
+#endif
+
+/*
+ * here, we make a definition for the externally accessible function
+ * in this file (this definition is required for static a module
+ * but strongly encouraged generally) it is used to instruct the
+ * modules include file to define the function prototypes.
+ */
+
+#define PAM_SM_SESSION
+#define PAM_SM_AUTH
+
+#include <security/pam_modules.h>
+#include <security/_pam_macros.h>
+
+/* some syslogging */
+
+static void _log_err(int err, const char *format, ...)
+{
+    va_list args;
+
+    va_start(args, format);
+    openlog("PAM-mail", LOG_CONS|LOG_PID, LOG_AUTH);
+    vsyslog(err, format, args);
+    va_end(args);
+    closelog();
+}
+
+/* argument parsing */
+
+#define PAM_DEBUG_ARG		0x0001
+#define PAM_NO_LOGIN		0x0002
+#define PAM_LOGOUT_TOO		0x0004
+#define PAM_NEW_MAIL_DIR	0x0010
+#define PAM_MAIL_SILENT		0x0020
+#define PAM_NO_ENV		0x0040
+#define PAM_HOME_MAIL		0x0100
+#define PAM_EMPTY_TOO		0x0200
+#define PAM_STANDARD_MAIL	0x0400
+#define PAM_QUIET_MAIL		0x1000
+
+static int _pam_parse(int flags, int argc, const char **argv, char **maildir,
+		      int *hashcount)
+{
+    int ctrl=0;
+
+    if (flags & PAM_SILENT) {
+	ctrl |= PAM_MAIL_SILENT;
+    }
+
+    *hashcount = 0;
+
+    /* step through arguments */
+    for (; argc-- > 0; ++argv) {
+
+	/* generic options */
+
+	if (!strcmp(*argv,"debug"))
+	    ctrl |= PAM_DEBUG_ARG;
+	else if (!strcmp(*argv,"quiet"))
+	    ctrl |= PAM_QUIET_MAIL;
+	else if (!strcmp(*argv,"standard"))
+	    ctrl |= PAM_STANDARD_MAIL | PAM_EMPTY_TOO;
+	else if (!strncmp(*argv,"dir=",4)) {
+	    *maildir = x_strdup(4+*argv);
+	    if (*maildir != NULL) {
+		D(("new mail directory: %s", *maildir));
+		ctrl |= PAM_NEW_MAIL_DIR;
+	    } else {
+		_log_err(LOG_CRIT,
+			 "failed to duplicate mail directory - ignored");
+	    }
+	} else if (!strncmp(*argv,"hash=",5)) {
+	    char *ep = NULL;
+	    *hashcount = strtol(*argv+5,&ep,10);
+	    if (!ep || (*hashcount < 0)) {
+		*hashcount = 0;
+	    }
+	} else if (!strcmp(*argv,"close")) {
+	    ctrl |= PAM_LOGOUT_TOO;
+	} else if (!strcmp(*argv,"nopen")) {
+	    ctrl |= PAM_NO_LOGIN;
+	} else if (!strcmp(*argv,"noenv")) {
+	    ctrl |= PAM_NO_ENV;
+	} else if (!strcmp(*argv,"empty")) {
+	    ctrl |= PAM_EMPTY_TOO;
+	} else {
+	    _log_err(LOG_ERR,"pam_parse: unknown option; %s",*argv);
+	}
+    }
+
+    if ((*hashcount != 0) && !(ctrl & PAM_NEW_MAIL_DIR)) {
+	*maildir = x_strdup(DEFAULT_MAIL_DIRECTORY);
+	ctrl |= PAM_NEW_MAIL_DIR;
+    }
+
+    return ctrl;
+}
+
+/* a front end for conversations */
+
+static int converse(pam_handle_t *pamh, int ctrl, int nargs
+		    , struct pam_message **message
+		    , struct pam_response **response)
+{
+    int retval;
+    struct pam_conv *conv;
+
+    D(("begin to converse"));
+
+    retval = pam_get_item( pamh, PAM_CONV, (const void **) &conv ) ; 
+    if ( retval == PAM_SUCCESS ) {
+
+	retval = conv->conv(nargs, ( const struct pam_message ** ) message
+			    , response, conv->appdata_ptr);
+
+	D(("returned from application's conversation function"));
+
+	if (retval != PAM_SUCCESS && (PAM_DEBUG_ARG & ctrl) ) {
+	    _log_err(LOG_DEBUG, "conversation failure [%s]"
+		     , pam_strerror(pamh, retval));
+	}
+
+    } else {
+	_log_err(LOG_ERR, "couldn't obtain coversation function [%s]"
+		 , pam_strerror(pamh, retval));
+    }
+
+    D(("ready to return from module conversation"));
+
+    return retval;                  /* propagate error status */
+}
+
+static int get_folder(pam_handle_t *pamh, int ctrl,
+		      char **path_mail, char **folder_p, int hashcount)
+{
+    int retval;
+    const char *user, *path;
+    char *folder;
+    const struct passwd *pwd=NULL;
+
+    retval = pam_get_user(pamh, &user, NULL);
+    if (retval != PAM_SUCCESS || user == NULL) {
+	_log_err(LOG_ERR, "no user specified");
+	return PAM_USER_UNKNOWN;
+    }
+
+    if (ctrl & PAM_NEW_MAIL_DIR) {
+	path = *path_mail;
+	if (*path == '~') {       /* support for $HOME delivery */
+	    pwd = getpwnam(user);
+	    if (pwd == NULL) {
+		_log_err(LOG_ERR, "user [%s] unknown", user);
+		_pam_overwrite(*path_mail);
+		_pam_drop(*path_mail);
+		return PAM_USER_UNKNOWN;
+	    }
+	    /*
+	     * "~/xxx" and "~xxx" are treated as same
+	     */
+	    if (!*++path || (*path == '/' && !*++path)) {
+		_log_err(LOG_ALERT, "badly formed mail path [%s]", *path_mail);
+		_pam_overwrite(*path_mail);
+		_pam_drop(*path_mail);
+		return PAM_ABORT;
+	    }
+	    ctrl |= PAM_HOME_MAIL;
+	    if (hashcount != 0) {
+		_log_err(LOG_ALERT, "can't do hash= and home directory mail");
+	    }
+	}
+    } else {
+	path = DEFAULT_MAIL_DIRECTORY;
+    }
+
+    /* put folder together */
+
+    if (ctrl & PAM_HOME_MAIL) {
+	folder = malloc(sizeof(MAIL_FILE_FORMAT)
+			+strlen(pwd->pw_dir)+strlen(path));
+    } else {
+	folder = malloc(sizeof(MAIL_FILE_FORMAT)+strlen(path)+strlen(user)
+			+2*hashcount);
+    }
+
+    if (folder != NULL) {
+	if (ctrl & PAM_HOME_MAIL) {
+	    sprintf(folder, MAIL_FILE_FORMAT, pwd->pw_dir, "", path);
+	} else {
+	    int i;
+	    char *hash = malloc(2*hashcount+1);
+
+	    if (hash) {
+		for (i = 0; i < hashcount; i++) {
+		    hash[2*i] = '/';
+		    hash[2*i+1] = user[i];
+		}
+		hash[2*i] = '\0';
+		sprintf(folder, MAIL_FILE_FORMAT, path, hash, user);
+		_pam_overwrite(hash);
+		_pam_drop(hash);
+	    } else {
+		sprintf(folder, "error");
+	    }
+	}
+	D(("folder =[%s]", folder));
+    }
+
+    /* tidy up */
+
+    _pam_overwrite(*path_mail);
+    _pam_drop(*path_mail);
+    user = NULL;
+
+    if (folder == NULL) {
+	_log_err(LOG_CRIT, "out of memory for mail folder");
+	return PAM_BUF_ERR;
+    }
+
+    *folder_p = folder;
+    folder = NULL;
+
+    return PAM_SUCCESS;
+}
+
+static const char *get_mail_status(int ctrl, const char *folder)
+{
+    const char *type = NULL;
+    static char dir[256];
+    struct stat mail_st;
+    struct dirent **namelist;
+    int i;
+
+    if (stat(folder, &mail_st) == 0) {
+	if (S_ISDIR(mail_st.st_mode)) { /* Assume Maildir format */
+	    sprintf(dir, "%.250s/new", folder);
+	    i = scandir(dir, &namelist, 0, alphasort);
+	    if (i > 2) {
+		type = "new";
+		while (--i)
+		    free(namelist[i]);
+	    } else {
+		while (--i >= 0)
+		    free(namelist[i]);
+		sprintf(dir, "%.250s/cur", folder);
+		i = scandir(dir, &namelist, 0, alphasort);
+		if (i > 2) {
+		    type = "old";
+		    while (--i)
+			free(namelist[i]);
+		} else if (ctrl & PAM_EMPTY_TOO) {
+		    while (--i >= 0)
+			free(namelist[i]);
+		    type = "no";
+		} else {
+		    type = NULL;
+		}
+	    }
+	} else {
+	    if (mail_st.st_size > 0) {
+		if (mail_st.st_atime < mail_st.st_mtime) /* new */
+		    type = (ctrl & PAM_STANDARD_MAIL) ? "new " : "new";
+		else /* old */
+		    type = (ctrl & PAM_STANDARD_MAIL) ? "" : "old";
+	    } else if (ctrl & PAM_EMPTY_TOO) {
+		type = "no";
+	    } else {
+		type = NULL;
+	    }
+	}
+    }
+
+    memset(dir, 0, 256);
+    memset(&mail_st, 0, sizeof(mail_st));
+    D(("user has %s mail in %s folder", type, folder));
+    return type;
+}
+
+static int report_mail(pam_handle_t *pamh, int ctrl
+		       , const char *type, const char *folder)
+{
+    int retval;
+
+    if (!(ctrl & PAM_MAIL_SILENT) || ((ctrl & PAM_QUIET_MAIL) && strcmp(type, "new"))) {
+	char *remark;
+
+	if (ctrl & PAM_STANDARD_MAIL)
+	    if (!strcmp(type, "no"))
+		remark = malloc(strlen(NO_MAIL_STANDARD_FORMAT)+1);
+	    else
+		remark = malloc(strlen(YOUR_MAIL_STANDARD_FORMAT)+strlen(type)+1);
+	else
+	    remark = malloc(strlen(YOUR_MAIL_VERBOSE_FORMAT)+strlen(type)+strlen(folder)+1);
+	if (remark == NULL) {
+	    retval = PAM_BUF_ERR;
+	} else {
+	    struct pam_message msg[1], *mesg[1];
+	    struct pam_response *resp=NULL;
+
+	    if (ctrl & PAM_STANDARD_MAIL)
+		if (!strcmp(type, "no"))
+		    sprintf(remark, NO_MAIL_STANDARD_FORMAT);
+		else
+		    sprintf(remark, YOUR_MAIL_STANDARD_FORMAT, type);
+	    else
+		sprintf(remark, YOUR_MAIL_VERBOSE_FORMAT, type, folder);
+
+	    mesg[0] = &msg[0];
+	    msg[0].msg_style = PAM_TEXT_INFO;
+	    msg[0].msg = remark;
+
+	    retval = converse(pamh, ctrl, 1, mesg, &resp);
+
+	    _pam_overwrite(remark);
+	    _pam_drop(remark);
+	    if (resp)
+		_pam_drop_reply(resp, 1);
+	}
+    } else {
+	D(("keeping quiet"));
+	retval = PAM_SUCCESS;
+    }
+
+    D(("returning %s", pam_strerror(pamh, retval)));
+    return retval;
+}
+
+static int _do_mail(pam_handle_t *, int, int, const char **, int);
+
+/* --- authentication functions --- */
+
+PAM_EXTERN
+int pam_sm_authenticate(pam_handle_t *pamh,int flags,int argc,
+    const char **argv)
+{
+    return PAM_IGNORE;
+}
+
+/* Checking mail as part of authentication */
+PAM_EXTERN
+int pam_sm_setcred(pam_handle_t *pamh, int flags, int argc,
+    const char **argv)
+{
+    if (!(flags & (PAM_ESTABLISH_CRED|PAM_DELETE_CRED)))
+      return PAM_IGNORE;
+    return _do_mail(pamh,flags,argc,argv,(flags & PAM_ESTABLISH_CRED));
+}
+
+/* --- session management functions --- */
+
+PAM_EXTERN
+int pam_sm_close_session(pam_handle_t *pamh,int flags,int argc
+			 ,const char **argv)
+{
+    return _do_mail(pamh,flags,argc,argv,0);;
+}
+
+/* Checking mail as part of the session management */
+PAM_EXTERN
+int pam_sm_open_session(pam_handle_t *pamh, int flags, int argc,
+    const char **argv)
+{
+    return _do_mail(pamh,flags,argc,argv,1);
+}
+
+
+/* --- The Beaf (Tm) --- */
+
+static int _do_mail(pam_handle_t *pamh, int flags, int argc,
+    const char **argv, int est)
+{
+    int retval, ctrl, hashcount;
+    char *path_mail=NULL, *folder;
+    const char *type;
+
+    /*
+     * this module (un)sets the MAIL environment variable, and checks if
+     * the user has any new mail.
+     */
+
+    ctrl = _pam_parse(flags, argc, argv, &path_mail, &hashcount);
+
+    /* Do we have anything to do? */
+
+    if (flags & PAM_SILENT)
+	return PAM_SUCCESS;
+
+    /* which folder? */
+
+    retval = get_folder(pamh, ctrl, &path_mail, &folder, hashcount);
+    if (retval != PAM_SUCCESS) {
+	D(("failed to find folder"));
+	return retval;
+    }
+
+    /* set the MAIL variable? */
+
+    if (!(ctrl & PAM_NO_ENV) && est) {
+	char *tmp;
+
+	tmp = malloc(strlen(folder)+sizeof(MAIL_ENV_FORMAT));
+	if (tmp != NULL) {
+	    sprintf(tmp, MAIL_ENV_FORMAT, folder);
+	    D(("setting env: %s", tmp));
+	    retval = pam_putenv(pamh, tmp);
+	    _pam_overwrite(tmp);
+	    _pam_drop(tmp);
+	    if (retval != PAM_SUCCESS) {
+		_pam_overwrite(folder);
+		_pam_drop(folder);
+		_log_err(LOG_CRIT, "unable to set " MAIL_ENV_NAME " variable");
+		return retval;
+	    }
+	} else {
+	    _log_err(LOG_CRIT, "no memory for " MAIL_ENV_NAME " variable");
+	    _pam_overwrite(folder);
+	    _pam_drop(folder);
+	    return retval;
+	}
+    } else {
+	D(("not setting " MAIL_ENV_NAME " variable"));
+    }
+
+    /*
+     * OK. we've got the mail folder... what about its status?
+     */
+
+    if ((est && !(ctrl & PAM_NO_LOGIN))
+	|| (!est && (ctrl & PAM_LOGOUT_TOO))) {
+	type = get_mail_status(ctrl, folder);
+	if (type != NULL) {
+	    retval = report_mail(pamh, ctrl, type, folder);
+	    type = NULL;
+	}
+    }
+    
+    /* Delete environment variable? */  
+    if (!est)
+	(void) pam_putenv(pamh, MAIL_ENV_NAME);
+
+    _pam_overwrite(folder); /* clean up */
+    _pam_drop(folder);
+
+    /* indicate success or failure */
+
+    return retval;
+}
+
+#ifdef PAM_STATIC
+
+/* static module data */
+
+struct pam_module _pam_mail_modstruct = {
+     "pam_mail",
+     pam_sm_authenticate,
+     pam_sm_setcred,
+     NULL,
+     pam_sm_open_session,
+     pam_sm_close_session,
+     NULL,
+};
+
+#endif
+
+/* end of module definition */