diff options
Diffstat (limited to 'examples/blank.c')
| -rw-r--r-- | examples/blank.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/examples/blank.c b/examples/blank.c new file mode 100644 index 0000000..9d51756 --- /dev/null +++ b/examples/blank.c @@ -0,0 +1,158 @@ +/* + * $Id$ + */ + +/* Andrew Morgan (morgan@parc.power.net) -- a self contained `blank' + * application + * + * I am not very proud of this code. It makes use of a possibly ill- + * defined pamh pointer to call pam_strerror() with. The reason that + * I was sloppy with this is historical (pam_strerror, prior to 0.59, + * did not require a pamh argument) and if this program is used as a + * model for anything, I should wish that you will take this error into + * account. + */ + +#include <stdio.h> +#include <stdlib.h> + +#include <security/pam_appl.h> +#include <security/pam_misc.h> + +/* ------ some local (static) functions ------- */ + +static void bail_out(pam_handle_t *pamh, int really, int code, const char *fn) +{ + fprintf(stderr,"==> called %s()\n got: `%s'\n", fn, + pam_strerror(pamh, code)); + if (really && code) + exit (1); +} + +/* ------ some static data objects ------- */ + +static struct pam_conv conv = { + misc_conv, + NULL +}; + +/* ------- the application itself -------- */ + +int main(int argc, char **argv) +{ + pam_handle_t *pamh=NULL; + char *username=NULL; + int retcode; + + /* did the user call with a username as an argument ? */ + + if (argc > 2) { + fprintf(stderr,"usage: %s [username]\n",argv[0]); + } else if (argc == 2) { + username = argv[1]; + } + + /* initialize the Linux-PAM library */ + retcode = pam_start("blank", username, &conv, &pamh); + bail_out(pamh,1,retcode,"pam_start"); + + /* test the environment stuff */ + { +#define MAXENV 15 + const char *greek[MAXENV] = { + "a=alpha", "b=beta", "c=gamma", "d=delta", "e=epsilon", + "f=phi", "g=psi", "h=eta", "i=iota", "j=mu", "k=nu", + "l=zeta", "h=", "d", "k=xi" + }; + char **env; + int i; + + for (i=0; i<MAXENV; ++i) { + retcode = pam_putenv(pamh,greek[i]); + bail_out(pamh,0,retcode,"pam_putenv"); + } + env = pam_getenvlist(pamh); + if (env) + env = pam_misc_drop_env(env); + else + fprintf(stderr,"???\n"); + fprintf(stderr,"a test: c=[%s], j=[%s]\n" + , pam_getenv(pamh, "c"), pam_getenv(pamh, "j")); + } + + /* to avoid using goto we abuse a loop here */ + for (;;) { + /* authenticate the user --- `0' here, could have been PAM_SILENT + * | PAM_DISALLOW_NULL_AUTHTOK */ + + retcode = pam_authenticate(pamh, 0); + bail_out(pamh,0,retcode,"pam_authenticate"); + + /* has the user proved themself valid? */ + if (retcode != PAM_SUCCESS) { + fprintf(stderr,"%s: invalid request\n",argv[0]); + break; + } + + /* the user is valid, but should they have access at this + time? */ + + retcode = pam_acct_mgmt(pamh, 0); /* `0' could be as above */ + bail_out(pamh,0,retcode,"pam_acct_mgmt"); + + if (retcode == PAM_NEW_AUTHTOK_REQD) { + fprintf(stderr,"Application must request new password...\n"); + retcode = pam_chauthtok(pamh,PAM_CHANGE_EXPIRED_AUTHTOK); + bail_out(pamh,0,retcode,"pam_chauthtok"); + } + + if (retcode != PAM_SUCCESS) { + fprintf(stderr,"%s: invalid request\n",argv[0]); + break; + } + + /* `0' could be as above */ + retcode = pam_setcred(pamh, PAM_ESTABLISH_CRED); + bail_out(pamh,0,retcode,"pam_setcred1"); + + if (retcode != PAM_SUCCESS) { + fprintf(stderr,"%s: problem setting user credentials\n" + ,argv[0]); + break; + } + + /* open a session for the user --- `0' could be PAM_SILENT */ + retcode = pam_open_session(pamh,0); + bail_out(pamh,0,retcode,"pam_open_session"); + if (retcode != PAM_SUCCESS) { + fprintf(stderr,"%s: problem opening a session\n",argv[0]); + break; + } + + fprintf(stderr,"The user has been authenticated and `logged in'\n"); + + /* close a session for the user --- `0' could be PAM_SILENT + * it is possible that this pam_close_call is in another program.. + */ + + retcode = pam_close_session(pamh,0); + bail_out(pamh,0,retcode,"pam_close_session"); + if (retcode != PAM_SUCCESS) { + fprintf(stderr,"%s: problem closing a session\n",argv[0]); + break; + } + + retcode = pam_setcred(pamh, PAM_DELETE_CRED); + bail_out(pamh,0,retcode,"pam_setcred2"); + + break; /* don't go on for ever! */ + } + + /* close the Linux-PAM library */ + retcode = pam_end(pamh, PAM_SUCCESS); + pamh = NULL; + + bail_out(pamh,1,retcode,"pam_end"); + + exit(0); +} |