py:dcerpc/raw_protocol: make use of assertPadding()

[Samba.git] / source3 / client / smbspool.c

/*
   Unix SMB/CIFS implementation.
   SMB backend for the Common UNIX Printing System ("CUPS")

   Copyright (C) Michael R Sweet            1999
   Copyright (C) Andrew Tridgell            1994-1998
   Copyright (C) Andrew Bartlett            2002
   Copyright (C) Rodrigo Fernandez-Vizarra  2005
   Copyright (C) James Peach                2008

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "includes.h"
#include "system/filesys.h"
#include "system/passwd.h"
#include "system/kerberos.h"
#include "libsmb/libsmb.h"
#include "lib/param/param.h"
#include "lib/krb5_wrap/krb5_samba.h"

/*
 * Starting with CUPS 1.3, Kerberos support is provided by cupsd including
 * the forwarding of user credentials via the authenticated session between
 * user and server and the KRB5CCNAME environment variable which will point
 * to a temporary file or an in-memory representation depending on the version
 * of Kerberos you use.  As a result, all of the ticket code that used to
 * live here has been removed, and we depend on the user session (if you
 * run smbspool by hand) or cupsd to provide the necessary Kerberos info.
 *
 * Also, the AUTH_USERNAME and AUTH_PASSWORD environment variables provide
 * for per-job authentication for non-Kerberized printing.  We use those
 * if there is no username and password specified in the device URI.
 *
 * Finally, if we have an authentication failure we return exit code 2
 * which tells CUPS to hold the job for authentication and bug the user
 * to get the necessary credentials.
 */

#define MAX_RETRY_CONNECT        3


/*
 * Globals...
 */



/*
 * Local functions...
 */

static int      get_exit_code(struct cli_state * cli, NTSTATUS nt_status, bool use_kerberos);
static void     list_devices(void);
static struct cli_state *smb_complete_connection(const char *, const char *,
        int, const char *, const char *, const char *, const char *, int, bool *need_auth);
static struct cli_state *smb_connect(const char *, const char *, int, const
        char *, const char *, const char *, const char *, bool *need_auth);
static int      smb_print(struct cli_state *, char *, FILE *);
static char    *uri_unescape_alloc(const char *);
#if 0
static bool     smb_encrypt;
#endif

/*
 * 'main()' - Main entry for SMB backend.
 */

int                             /* O - Exit status */
main(int argc,                  /* I - Number of command-line arguments */
     char *argv[])
{                               /* I - Command-line arguments */
        int             i;      /* Looping var */
        int             copies; /* Number of copies */
        int             port;   /* Port number */
        char            uri[1024],      /* URI */
                       *sep,    /* Pointer to separator */
                       *tmp, *tmp2,     /* Temp pointers to do escaping */
                       *password;       /* Password */
        char           *username,       /* Username */
                       *server, /* Server name */
                       *printer;/* Printer name */
        const char     *workgroup;      /* Workgroup */
        FILE           *fp;     /* File to print */
        int             status = 1;     /* Status of LPD job */
        struct cli_state *cli;  /* SMB interface */
        char            empty_str[] = "";
        int             tries = 0;
        bool            need_auth = true;
        const char     *dev_uri;
        const char     *config_file = NULL;
        TALLOC_CTX     *frame = talloc_stackframe();
        bool device_uri_cmdline = false;
        const char *print_file = NULL;
        const char *print_copies = NULL;
        int cmp;
        int len;

        if (argc == 1) {
                /*
                 * NEW!  In CUPS 1.1 the backends are run with no arguments
                 * to list the available devices.  These can be devices
                 * served by this backend or any other backends (i.e. you
                 * can have an SNMP backend that is only used to enumerate
                 * the available network printers... :)
                 */

                list_devices();
                status = 0;
                goto done;
        }

        /*
         * We need at least 5 options if the DEVICE_URI is passed via an env
         * variable and printing data comes via stdin.
         * We don't accept more than 7 options in total, including optional.
         */
        if (argc < 5 || argc > 8) {
                fprintf(stderr,
"Usage: %s [DEVICE_URI] job-id user title copies options [file]\n"
"       The DEVICE_URI environment variable can also contain the\n"
"       destination printer:\n"
"\n"
"           smb://[username:password@][workgroup/]server[:port]/printer\n",
                        argv[0]);
                goto done;
        }

        /*
         * If we have 6 arguments find out if we have the device_uri from the
         * command line or the print data
         */
        if (argc == 7) {
                cmp = strncmp(argv[1], "smb://", 6);
                if (cmp == 0) {
                        device_uri_cmdline = true;
                } else {
                        print_copies = argv[4];
                        print_file = argv[6];
                }
        } else if (argc == 8) {
                device_uri_cmdline = true;
                print_copies = argv[5];
                print_file = argv[7];
        }

        if (print_file != NULL) {
                char *endp;

                fp = fopen(print_file, "rb");
                if (fp == NULL) {
                        perror("ERROR: Unable to open print file");
                        goto done;
                }

                copies = strtol(print_copies, &endp, 10);
                if (print_copies == endp) {
                        perror("ERROR: Unable to determine number of copies");
                        goto done;
                }
        } else {
                fp = stdin;
                copies = 1;
        }

        /*
         * Find the URI ...
         */
        if (device_uri_cmdline) {
                dev_uri = argv[1];
        } else {
                dev_uri = getenv("DEVICE_URI");
                if (dev_uri == NULL || strlen(dev_uri) == 0) {
                        dev_uri = "";
                }
        }

        cmp = strncmp(dev_uri, "smb://", 6);
        if (cmp != 0) {
                fprintf(stderr,
                        "ERROR: No valid device URI has been specified\n");
                goto done;
        }
        len = snprintf(uri, sizeof(uri), "%s", dev_uri);
        if (len >= sizeof(uri)) {
                fprintf(stderr,
                        "ERROR: The URI is too long.\n");
                goto done;
        }

        /*
         * Extract the destination from the URI...
         */

        if ((sep = strrchr_m(uri, '@')) != NULL) {
                tmp = uri + 6;
                *sep++ = '\0';

                /* username is in tmp */

                server = sep;

                /*
                 * Extract password as needed...
                 */

                if ((tmp2 = strchr_m(tmp, ':')) != NULL) {
                        *tmp2++ = '\0';
                        password = uri_unescape_alloc(tmp2);
                } else {
                        password = empty_str;
                }
                username = uri_unescape_alloc(tmp);
        } else {
                if ((username = getenv("AUTH_USERNAME")) == NULL) {
                        username = empty_str;
                }

                if ((password = getenv("AUTH_PASSWORD")) == NULL) {
                        password = empty_str;
                }

                server = uri + 6;
        }

        tmp = server;

        if ((sep = strchr_m(tmp, '/')) == NULL) {
                fputs("ERROR: Bad URI - need printer name!\n", stderr);
                goto done;
        }

        *sep++ = '\0';
        tmp2 = sep;

        if ((sep = strchr_m(tmp2, '/')) != NULL) {
                /*
                 * Convert to smb://[username:password@]workgroup/server/printer...
                 */

                *sep++ = '\0';

                workgroup = uri_unescape_alloc(tmp);
                server = uri_unescape_alloc(tmp2);
                printer = uri_unescape_alloc(sep);
        } else {
                workgroup = NULL;
                server = uri_unescape_alloc(tmp);
                printer = uri_unescape_alloc(tmp2);
        }

        if ((sep = strrchr_m(server, ':')) != NULL) {
                *sep++ = '\0';

                port = atoi(sep);
        } else {
                port = 0;
        }

        /*
         * Setup the SAMBA server state...
         */

        setup_logging("smbspool", DEBUG_STDERR);

        smb_init_locale();

        config_file = lp_default_path();
        if (!lp_load_client(config_file)) {
                fprintf(stderr,
                        "ERROR: Can't load %s - run testparm to debug it\n",
                        config_file);
                goto done;
        }

        if (workgroup == NULL) {
                workgroup = lp_workgroup();
        }

        load_interfaces();

        do {
                cli = smb_connect(workgroup, server, port, printer,
                        username, password, argv[3], &need_auth);
                if (cli == NULL) {
                        if (need_auth) {
                                exit(2);
                        } else if (getenv("CLASS") == NULL) {
                                fprintf(stderr, "ERROR: Unable to connect to CIFS host, will retry in 60 seconds...\n");
                                sleep(60);
                                tries++;
                        } else {
                                fprintf(stderr, "ERROR: Unable to connect to CIFS host, trying next printer...\n");
                                goto done;
                        }
                }
        } while ((cli == NULL) && (tries < MAX_RETRY_CONNECT));

        if (cli == NULL) {
                fprintf(stderr, "ERROR: Unable to connect to CIFS host after (tried %d times)\n", tries);
                goto done;
        }

        /*
         * Now that we are connected to the server, ignore SIGTERM so that we
         * can finish out any page data the driver sends (e.g. to eject the
         * current page...  Only ignore SIGTERM if we are printing data from
         * stdin (otherwise you can't cancel raw jobs...)
         */

        if (argc < 7) {
                CatchSignal(SIGTERM, SIG_IGN);
        }

        /*
         * Queue the job...
         */

        for (i = 0; i < copies; i++) {
                status = smb_print(cli, argv[4] /* title */ , fp);
                if (status != 0) {
                        break;
                }
        }

        cli_shutdown(cli);

        /*
         * Return the queue status...
         */

done:

        TALLOC_FREE(frame);
        return (status);
}


/*
 * 'get_exit_code()' - Get the backend exit code based on the current error.
 */

static int
get_exit_code(struct cli_state * cli,
              NTSTATUS nt_status,
              bool use_kerberos)
{
        int i;

        /* List of NTSTATUS errors that are considered
         * authentication errors
         */
        static const NTSTATUS auth_errors[] =
        {
                NT_STATUS_ACCESS_DENIED, NT_STATUS_ACCESS_VIOLATION,
                NT_STATUS_SHARING_VIOLATION, NT_STATUS_PRIVILEGE_NOT_HELD,
                NT_STATUS_INVALID_ACCOUNT_NAME, NT_STATUS_NO_SUCH_USER,
                NT_STATUS_WRONG_PASSWORD, NT_STATUS_LOGON_FAILURE,
                NT_STATUS_ACCOUNT_RESTRICTION, NT_STATUS_INVALID_LOGON_HOURS,
                NT_STATUS_PASSWORD_EXPIRED, NT_STATUS_ACCOUNT_DISABLED
        };


        fprintf(stderr, "DEBUG: get_exit_code(cli=%p, nt_status=%s [%x])\n",
                cli, nt_errstr(nt_status), NT_STATUS_V(nt_status));

        for (i = 0; i < ARRAY_SIZE(auth_errors); i++) {
                if (!NT_STATUS_EQUAL(nt_status, auth_errors[i])) {
                        continue;
                }

                if (cli) {
                        if (use_kerberos)
                                fputs("ATTR: auth-info-required=negotiate\n", stderr);
                        else
                                fputs("ATTR: auth-info-required=username,password\n", stderr);
                }

                /*
                 * 2 = authentication required...
                 */

                return (2);

        }

        /*
         * 1 = fail
         */

        return (1);
}


/*
 * 'list_devices()' - List the available printers seen on the network...
 */

static void
list_devices(void)
{
        /*
         * Eventually, search the local workgroup for available hosts and printers.
         */

        puts("network smb \"Unknown\" \"Windows Printer via SAMBA\"");
}


static struct cli_state *
smb_complete_connection(const char *myname,
                        const char *server,
                        int port,
                        const char *username,
                        const char *password,
                        const char *workgroup,
                        const char *share,
                        int flags,
                        bool *need_auth)
{
        struct cli_state *cli;  /* New connection */
        NTSTATUS        nt_status;
        struct cli_credentials *creds = NULL;
        bool use_kerberos = false;

        /* Start the SMB connection */
        *need_auth = false;
        nt_status = cli_start_connection(&cli, myname, server, NULL, port,
                                         SMB_SIGNING_DEFAULT, flags);
        if (!NT_STATUS_IS_OK(nt_status)) {
                fprintf(stderr, "ERROR: Connection failed: %s\n", nt_errstr(nt_status));
                return NULL;
        }

        /*
         * We pretty much guarantee password must be valid or a pointer to a
         * 0 char.
         */
        if (!password) {
                *need_auth = true;
                return NULL;
        }

        if (flags & CLI_FULL_CONNECTION_USE_KERBEROS) {
                use_kerberos = true;
        }

        creds = cli_session_creds_init(cli,
                                       username,
                                       workgroup,
                                       NULL, /* realm */
                                       password,
                                       use_kerberos,
                                       false, /* fallback_after_kerberos */
                                       false, /* use_ccache */
                                       false); /* password_is_nt_hash */
        if (creds == NULL) {
                fprintf(stderr, "ERROR: cli_session_creds_init failed\n");
                cli_shutdown(cli);
                return NULL;
        }

        nt_status = cli_session_setup_creds(cli, creds);
        if (!NT_STATUS_IS_OK(nt_status)) {
                fprintf(stderr, "ERROR: Session setup failed: %s\n", nt_errstr(nt_status));

                if (get_exit_code(cli, nt_status, use_kerberos) == 2) {
                        *need_auth = true;
                }

                cli_shutdown(cli);

                return NULL;
        }

        nt_status = cli_tree_connect_creds(cli, share, "?????", creds);
        if (!NT_STATUS_IS_OK(nt_status)) {
                fprintf(stderr, "ERROR: Tree connect failed (%s)\n",
                        nt_errstr(nt_status));

                if (get_exit_code(cli, nt_status, use_kerberos) == 2) {
                        *need_auth = true;
                }

                cli_shutdown(cli);

                return NULL;
        }
#if 0
        /* Need to work out how to specify this on the URL. */
        if (smb_encrypt) {
                if (!cli_cm_force_encryption_creds(cli, creds, share)) {
                        fprintf(stderr, "ERROR: encryption setup failed\n");
                        cli_shutdown(cli);
                        return NULL;
                }
        }
#endif

        return cli;
}

static bool kerberos_ccache_is_valid(void) {
        krb5_context ctx;
        const char *ccache_name = NULL;
        krb5_ccache ccache = NULL;
        krb5_error_code code;

        code = smb_krb5_init_context_common(&ctx);
        if (code != 0) {
                DBG_ERR("kerberos init context failed (%s)\n",
                        error_message(code));
                return false;
        }

        ccache_name = krb5_cc_default_name(ctx);
        if (ccache_name == NULL) {
                krb5_free_context(ctx);
                return false;
        }

        code = krb5_cc_resolve(ctx, ccache_name, &ccache);
        if (code != 0) {
                krb5_free_context(ctx);
                return false;
        } else {
                krb5_principal default_princ = NULL;

                code = krb5_cc_get_principal(ctx,
                                             ccache,
                                             &default_princ);
                if (code != 0) {
                        krb5_cc_close(ctx, ccache);
                        krb5_free_context(ctx);
                        return false;
                }
                krb5_free_principal(ctx, default_princ);
        }
        krb5_cc_close(ctx, ccache);
        krb5_free_context(ctx);

        return true;
}

/*
 * 'smb_connect()' - Return a connection to a server.
 */

static struct cli_state *       /* O - SMB connection */
smb_connect(const char *workgroup,      /* I - Workgroup */
            const char *server, /* I - Server */
            const int port,     /* I - Port */
            const char *share,  /* I - Printer */
            const char *username,       /* I - Username */
            const char *password,       /* I - Password */
            const char *jobusername,    /* I - User who issued the print job */
            bool *need_auth)
{                               /* O - Need authentication? */
        struct cli_state *cli;  /* New connection */
        char           *myname = NULL;  /* Client name */
        struct passwd  *pwd;

        /*
         * Get the names and addresses of the client and server...
         */
        myname = get_myname(talloc_tos());
        if (!myname) {
                return NULL;
        }

        /*
         * See if we have a username first.  This is for backwards compatible
         * behavior with 3.0.14a
         */

        if (username != NULL && username[0] != '\0') {
                if (kerberos_ccache_is_valid()) {
                        goto kerberos_auth;
                }
        }

        cli = smb_complete_connection(myname,
                                      server,
                                      port,
                                      username,
                                      password,
                                      workgroup,
                                      share,
                                      0,
                                      need_auth);
        if (cli != NULL) {
                fputs("DEBUG: Connected with username/password...\n", stderr);
                return (cli);
        }

kerberos_auth:
        /*
         * Try to use the user kerberos credentials (if any) to authenticate
         */
        cli = smb_complete_connection(myname, server, port, jobusername, "",
                                      workgroup, share,
                                 CLI_FULL_CONNECTION_USE_KERBEROS, need_auth);

        if (cli) {
                fputs("DEBUG: Connected using Kerberos...\n", stderr);
                return (cli);
        }

        /* give a chance for a passwordless NTLMSSP session setup */
        pwd = getpwuid(geteuid());
        if (pwd == NULL) {
                return NULL;
        }

        cli = smb_complete_connection(myname, server, port, pwd->pw_name, "",
                                      workgroup, share, 0, need_auth);

        if (cli) {
                fputs("DEBUG: Connected with NTLMSSP...\n", stderr);
                return (cli);
        }

        /*
         * last try. Use anonymous authentication
         */

        cli = smb_complete_connection(myname, server, port, "", "",
                                      workgroup, share, 0, need_auth);
        /*
         * Return the new connection...
         */

        return (cli);
}


/*
 * 'smb_print()' - Queue a job for printing using the SMB protocol.
 */

static int                      /* O - 0 = success, non-0 = failure */
smb_print(struct cli_state * cli,       /* I - SMB connection */
          char *title,          /* I - Title/job name */
          FILE * fp)
{                               /* I - File to print */
        uint16_t             fnum;      /* File number */
        int             nbytes, /* Number of bytes read */
                        tbytes; /* Total bytes read */
        char            buffer[8192],   /* Buffer for copy */
                       *ptr;    /* Pointer into title */
        NTSTATUS nt_status;


        /*
         * Sanitize the title...
         */

        for (ptr = title; *ptr; ptr++) {
                if (!isalnum((int) *ptr) && !isspace((int) *ptr)) {
                        *ptr = '_';
                }
        }

        /*
         * Open the printer device...
         */

        nt_status = cli_open(cli, title, O_RDWR | O_CREAT | O_TRUNC, DENY_NONE,
                          &fnum);
        if (!NT_STATUS_IS_OK(nt_status)) {
                fprintf(stderr, "ERROR: %s opening remote spool %s\n",
                        nt_errstr(nt_status), title);
                return get_exit_code(cli, nt_status, false);
        }

        /*
         * Copy the file to the printer...
         */

        if (fp != stdin)
                rewind(fp);

        tbytes = 0;

        while ((nbytes = fread(buffer, 1, sizeof(buffer), fp)) > 0) {
                NTSTATUS status;

                status = cli_writeall(cli, fnum, 0, (uint8_t *)buffer,
                                      tbytes, nbytes, NULL);
                if (!NT_STATUS_IS_OK(status)) {
                        int ret = get_exit_code(cli, status, false);
                        fprintf(stderr, "ERROR: Error writing spool: %s\n",
                                nt_errstr(status));
                        fprintf(stderr, "DEBUG: Returning status %d...\n",
                                ret);
                        cli_close(cli, fnum);

                        return (ret);
                }
                tbytes += nbytes;
        }

        nt_status = cli_close(cli, fnum);
        if (!NT_STATUS_IS_OK(nt_status)) {
                fprintf(stderr, "ERROR: %s closing remote spool %s\n",
                        nt_errstr(nt_status), title);
                return get_exit_code(cli, nt_status, false);
        } else {
                return (0);
        }
}

static char *
uri_unescape_alloc(const char *uritok)
{
        char *ret;
        char *end;
        ret = (char *) SMB_STRDUP(uritok);
        if (!ret) {
                return NULL;
        }

        end = rfc1738_unescape(ret);
        if (end == NULL) {
                free(ret);
                return NULL;
        }
        return ret;
}