cifs.upcall: declare a structure for holding decoded args
[sfrench/samba-autobuild/.git] / client / cifs.upcall.c
index 82b9f7b91ba46fd36798bc91b4475d39177e0b02..0ddcc75660c1cfc333d7fbb3f716eeaa8a16e5b2 100644 (file)
@@ -32,11 +32,11 @@ create dns_resolver * * /usr/local/sbin/cifs.upcall %k
 
 const char *CIFSSPNEGO_VERSION = "1.2";
 static const char *prog = "cifs.upcall";
-typedef enum _secType {
+typedef enum _sectype {
        NONE = 0,
        KRB5,
        MS_KRB5
-} secType_t;
+} sectype_t;
 
 /*
  * given a process ID, get the value of the KRB5CCNAME environment variable
@@ -58,14 +58,20 @@ get_krb5_ccname(pid_t pid)
        buf[4095] = '\0';
        snprintf(buf, 4095, "/proc/%d/environ", pid);
        fd = open(buf, O_RDONLY);
-       if (fd < 0)
+       if (fd < 0) {
+               syslog(LOG_DEBUG, "%s: unable to open %s: %d", __func__, buf,
+                       errno);
                return NULL;
+       }
 
        /* FIXME: don't assume that we get it all in the first read? */
        len = read(fd, buf, 4096);
        close(fd);
-       if (len < 0)
+       if (len < 0) {
+               syslog(LOG_DEBUG, "%s: unable to read from /proc/%d/environ: "
+                                 "%d", __func__, pid, errno);
                return NULL;
+       }
 
        left = len;
        p = buf;
@@ -83,6 +89,8 @@ get_krb5_ccname(pid_t pid)
                value = SMB_STRNDUP(p, left);
                break;
        }
+       syslog(LOG_DEBUG, "%s: KRB5CCNAME=%s", __func__,
+                               value ? value : "(null)");
        return value;
 }
 
@@ -105,7 +113,7 @@ get_krb5_ccname(pid_t pid)
  *     sess_key-       pointer for SessionKey data to be stored
  *
  * ret: 0 - success, others - failure
-*/
+ */
 static int
 handle_krb5_mech(const char *oid, const char *principal, DATA_BLOB *secblob,
                 DATA_BLOB *sess_key, const char *ccname)
@@ -113,12 +121,20 @@ handle_krb5_mech(const char *oid, const char *principal, DATA_BLOB *secblob,
        int retval;
        DATA_BLOB tkt, tkt_wrapped;
 
+       syslog(LOG_DEBUG, "%s: getting service ticket for %s", __func__,
+                         principal);
+
        /* get a kerberos ticket for the service and extract the session key */
        retval = cli_krb5_get_ticket(principal, 0, &tkt, sess_key, 0, ccname,
                                     NULL);
 
-       if (retval)
+       if (retval) {
+               syslog(LOG_DEBUG, "%s: failed to obtain service ticket (%d)",
+                                 __func__, retval);
                return retval;
+       }
+
+       syslog(LOG_DEBUG, "%s: obtained service ticket", __func__);
 
        /* wrap that up in a nice GSS-API wrapping */
        tkt_wrapped = spnego_gen_krb5_wrap(tkt, TOK_ID_KRB_AP_REQ);
@@ -131,18 +147,25 @@ handle_krb5_mech(const char *oid, const char *principal, DATA_BLOB *secblob,
        return retval;
 }
 
-#define DKD_HAVE_HOSTNAME      1
-#define DKD_HAVE_VERSION       2
-#define DKD_HAVE_SEC           4
-#define DKD_HAVE_IPV4          8
-#define DKD_HAVE_IPV6          16
-#define DKD_HAVE_UID           32
-#define DKD_HAVE_PID           64
+#define DKD_HAVE_HOSTNAME      0x1
+#define DKD_HAVE_VERSION       0x2
+#define DKD_HAVE_SEC           0x4
+#define DKD_HAVE_IPV4          0x8
+#define DKD_HAVE_IPV6          0x10
+#define DKD_HAVE_UID           0x20
+#define DKD_HAVE_PID           0x40
 #define DKD_MUSTHAVE_SET (DKD_HAVE_HOSTNAME|DKD_HAVE_VERSION|DKD_HAVE_SEC)
 
+static struct decoded_args {
+       int             ver;
+       char            *hostname;
+       uid_t           uid;
+       pid_t           pid;
+       sectype_t       sec;
+};
+
 static int
-decode_key_description(const char *desc, int *ver, secType_t *sec,
-                          char **hostname, uid_t *uid, pid_t *pid)
+decode_key_description(const char *desc, struct decoded_args *arg)
 {
        int retval = 0;
        char *pos;
@@ -153,15 +176,15 @@ decode_key_description(const char *desc, int *ver, secType_t *sec,
                if (strncmp(tkn, "host=", 5) == 0) {
                        int len;
 
-                       if (pos == NULL) {
+                       if (pos == NULL)
                                len = strlen(tkn);
-                       } else {
+                       else
                                len = pos - tkn;
-                       }
+
                        len -= 4;
-                       SAFE_FREE(*hostname);
-                       *hostname = SMB_XMALLOC_ARRAY(char, len);
-                       strlcpy(*hostname, tkn + 5, len);
+                       SAFE_FREE(arg->hostname);
+                       arg->hostname = SMB_XMALLOC_ARRAY(char, len);
+                       strlcpy(arg->hostname, tkn + 5, len);
                        retval |= DKD_HAVE_HOSTNAME;
                } else if (strncmp(tkn, "ipv4=", 5) == 0) {
                        /* BB: do we need it if we have hostname already? */
@@ -169,9 +192,9 @@ decode_key_description(const char *desc, int *ver, secType_t *sec,
                        /* BB: do we need it if we have hostname already? */
                } else if (strncmp(tkn, "pid=", 4) == 0) {
                        errno = 0;
-                       *pid = strtol(tkn + 4, NULL, 0);
+                       arg->pid = strtol(tkn + 4, NULL, 0);
                        if (errno != 0) {
-                               syslog(LOG_WARNING, "Invalid pid format: %s",
+                               syslog(LOG_ERR, "Invalid pid format: %s",
                                       strerror(errno));
                                return 1;
                        } else {
@@ -180,16 +203,16 @@ decode_key_description(const char *desc, int *ver, secType_t *sec,
                } else if (strncmp(tkn, "sec=", 4) == 0) {
                        if (strncmp(tkn + 4, "krb5", 4) == 0) {
                                retval |= DKD_HAVE_SEC;
-                               *sec = KRB5;
+                               arg->sec = KRB5;
                        } else if (strncmp(tkn + 4, "mskrb5", 6) == 0) {
                                retval |= DKD_HAVE_SEC;
-                               *sec = MS_KRB5;
+                               arg->sec = MS_KRB5;
                        }
                } else if (strncmp(tkn, "uid=", 4) == 0) {
                        errno = 0;
-                       *uid = strtol(tkn + 4, NULL, 16);
+                       arg->uid = strtol(tkn + 4, NULL, 16);
                        if (errno != 0) {
-                               syslog(LOG_WARNING, "Invalid uid format: %s",
+                               syslog(LOG_ERR, "Invalid uid format: %s",
                                       strerror(errno));
                                return 1;
                        } else {
@@ -197,10 +220,9 @@ decode_key_description(const char *desc, int *ver, secType_t *sec,
                        }
                } else if (strncmp(tkn, "ver=", 4) == 0) {      /* if version */
                        errno = 0;
-                       *ver = strtol(tkn + 4, NULL, 16);
+                       arg->ver = strtol(tkn + 4, NULL, 16);
                        if (errno != 0) {
-                               syslog(LOG_WARNING,
-                                      "Invalid version format: %s",
+                               syslog(LOG_ERR, "Invalid version format: %s",
                                       strerror(errno));
                                return 1;
                        } else {
@@ -226,7 +248,7 @@ cifs_resolver(const key_serial_t key, const char *key_descr)
        for (c = 1; c <= 4; c++) {
                keyend = index(keyend+1, ';');
                if (!keyend) {
-                       syslog(LOG_WARNING, "invalid key description: %s",
+                       syslog(LOG_ERR, "invalid key description: %s",
                                        key_descr);
                        return 1;
                }
@@ -236,20 +258,19 @@ cifs_resolver(const key_serial_t key, const char *key_descr)
        /* resolve name to ip */
        c = getaddrinfo(keyend, NULL, NULL, &addr);
        if (c) {
-               syslog(LOG_WARNING, "unable to resolve hostname: %s [%s]",
+               syslog(LOG_ERR, "unable to resolve hostname: %s [%s]",
                                keyend, gai_strerror(c));
                return 1;
        }
 
        /* conver ip to string form */
-       if (addr->ai_family == AF_INET) {
+       if (addr->ai_family == AF_INET)
                p = &(((struct sockaddr_in *)addr->ai_addr)->sin_addr);
-       } else {
+       else
                p = &(((struct sockaddr_in6 *)addr->ai_addr)->sin6_addr);
-       }
+
        if (!inet_ntop(addr->ai_family, p, ip, sizeof(ip))) {
-               syslog(LOG_WARNING, "%s: inet_ntop: %s",
-                               __FUNCTION__, strerror(errno));
+               syslog(LOG_ERR, "%s: inet_ntop: %s", __func__, strerror(errno));
                freeaddrinfo(addr);
                return 1;
        }
@@ -257,8 +278,8 @@ cifs_resolver(const key_serial_t key, const char *key_descr)
        /* setup key */
        c = keyctl_instantiate(key, ip, strlen(ip)+1, 0);
        if (c == -1) {
-               syslog(LOG_WARNING, "%s: keyctl_instantiate: %s",
-                               __FUNCTION__, strerror(errno));
+               syslog(LOG_ERR, "%s: keyctl_instantiate: %s", __func__,
+                               strerror(errno));
                freeaddrinfo(addr);
                return 1;
        }
@@ -270,7 +291,7 @@ cifs_resolver(const key_serial_t key, const char *key_descr)
 static void
 usage(void)
 {
-       syslog(LOG_WARNING, "Usage: %s [-c] [-v] key_serial", prog);
+       syslog(LOG_INFO, "Usage: %s [-c] [-v] key_serial", prog);
        fprintf(stderr, "Usage: %s [-c] [-v] key_serial\n", prog);
 }
 
@@ -279,33 +300,27 @@ int main(const int argc, char *const argv[])
        struct cifs_spnego_msg *keydata = NULL;
        DATA_BLOB secblob = data_blob_null;
        DATA_BLOB sess_key = data_blob_null;
-       secType_t sectype = NONE;
        key_serial_t key = 0;
        size_t datalen;
        long rc = 1;
-       uid_t uid = 0;
-       pid_t pid = 0;
-       int kernel_upcall_version = 0;
        int c, use_cifs_service_prefix = 0;
-       char *buf, *ccname = NULL, *hostname = NULL;
+       char *buf, *princ, *ccname = NULL;
+       struct decoded_args arg = { };
        const char *oid;
 
        openlog(prog, 0, LOG_DAEMON);
 
        while ((c = getopt(argc, argv, "cv")) != -1) {
                switch (c) {
-               case 'c':{
+               case 'c':
                        use_cifs_service_prefix = 1;
                        break;
-                       }
-               case 'v':{
+               case 'v':
                        printf("version: %s\n", CIFSSPNEGO_VERSION);
                        goto out;
-                       }
-               default:{
-                       syslog(LOG_WARNING, "unknown option: %c", c);
+               default:
+                       syslog(LOG_ERR, "unknown option: %c", c);
                        goto out;
-                       }
                }
        }
 
@@ -320,96 +335,89 @@ int main(const int argc, char *const argv[])
        key = strtol(argv[optind], NULL, 10);
        if (errno != 0) {
                key = 0;
-               syslog(LOG_WARNING, "Invalid key format: %s", strerror(errno));
+               syslog(LOG_ERR, "Invalid key format: %s", strerror(errno));
                goto out;
        }
 
        rc = keyctl_describe_alloc(key, &buf);
        if (rc == -1) {
-               syslog(LOG_WARNING, "keyctl_describe_alloc failed: %s",
+               syslog(LOG_ERR, "keyctl_describe_alloc failed: %s",
                       strerror(errno));
                rc = 1;
                goto out;
        }
 
+       syslog(LOG_DEBUG, "key description: %s", buf);
+
        if ((strncmp(buf, "cifs.resolver", sizeof("cifs.resolver")-1) == 0) ||
            (strncmp(buf, "dns_resolver", sizeof("dns_resolver")-1) == 0)) {
                rc = cifs_resolver(key, buf);
                goto out;
        }
 
-       rc = decode_key_description(buf, &kernel_upcall_version, &sectype,
-                                   &hostname, &uid, &pid);
+       rc = decode_key_description(buf, &arg);
        if ((rc & DKD_MUSTHAVE_SET) != DKD_MUSTHAVE_SET) {
-               syslog(LOG_WARNING,
-                      "unable to get from description necessary params");
+               syslog(LOG_ERR, "unable to get necessary params from key "
+                               "description (0x%x)", rc);
                rc = 1;
                SAFE_FREE(buf);
                goto out;
        }
        SAFE_FREE(buf);
 
-       if (kernel_upcall_version > CIFS_SPNEGO_UPCALL_VERSION) {
-               syslog(LOG_WARNING,
-                      "incompatible kernel upcall version: 0x%x",
-                      kernel_upcall_version);
+       if (arg.ver > CIFS_SPNEGO_UPCALL_VERSION) {
+               syslog(LOG_ERR, "incompatible kernel upcall version: 0x%x",
+                               arg.ver);
                rc = 1;
                goto out;
        }
 
        if (rc & DKD_HAVE_PID)
-               ccname = get_krb5_ccname(pid);
+               ccname = get_krb5_ccname(arg.pid);
 
        if (rc & DKD_HAVE_UID) {
-               rc = setuid(uid);
+               rc = setuid(arg.uid);
                if (rc == -1) {
-                       syslog(LOG_WARNING, "setuid: %s", strerror(errno));
+                       syslog(LOG_ERR, "setuid: %s", strerror(errno));
                        goto out;
                }
        }
 
        // do mech specific authorization
-       switch (sectype) {
+       switch (arg.sec) {
        case MS_KRB5:
-       case KRB5:{
-                       char *princ;
-                       size_t len;
-
-                       /* for "cifs/" service name + terminating 0 */
-                       len = strlen(hostname) + 5 + 1;
-                       princ = SMB_XMALLOC_ARRAY(char, len);
-                       if (!princ) {
-                               rc = 1;
-                               break;
-                       }
-                       if (use_cifs_service_prefix) {
-                               strlcpy(princ, "cifs/", len);
-                       } else {
-                               strlcpy(princ, "host/", len);
-                       }
-                       strlcpy(princ + 5, hostname, len - 5);
-
-                       if (sectype == MS_KRB5)
-                               oid = OID_KERBEROS5_OLD;
-                       else
-                               oid = OID_KERBEROS5;
-
-                       rc = handle_krb5_mech(oid, princ, &secblob, &sess_key,
-                                             ccname);
-                       SAFE_FREE(princ);
-                       break;
-               }
-       default:{
-                       syslog(LOG_WARNING, "sectype: %d is not implemented",
-                              sectype);
+       case KRB5:
+               /* for "cifs/" service name + terminating 0 */
+               datalen = strlen(arg.hostname) + 5 + 1;
+               princ = SMB_XMALLOC_ARRAY(char, datalen);
+               if (!princ) {
                        rc = 1;
                        break;
                }
+
+               if (use_cifs_service_prefix)
+                       strlcpy(princ, "cifs/", datalen);
+               else
+                       strlcpy(princ, "host/", datalen);
+
+               strlcpy(princ + 5, arg.hostname, datalen - 5);
+
+               if (arg.sec == MS_KRB5)
+                       oid = OID_KERBEROS5_OLD;
+               else
+                       oid = OID_KERBEROS5;
+
+               rc = handle_krb5_mech(oid, princ, &secblob, &sess_key, ccname);
+               SAFE_FREE(princ);
+               break;
+       default:
+               syslog(LOG_ERR, "sectype: %d is not implemented", arg.sec);
+               rc = 1;
+               break;
        }
 
-       if (rc) {
+       if (rc)
                goto out;
-       }
 
        /* pack SecurityBLob and SessionKey into downcall packet */
        datalen =
@@ -419,7 +427,7 @@ int main(const int argc, char *const argv[])
                rc = 1;
                goto out;
        }
-       keydata->version = kernel_upcall_version;
+       keydata->version = arg.ver;
        keydata->flags = 0;
        keydata->sesskey_len = sess_key.length;
        keydata->secblob_len = secblob.length;
@@ -430,7 +438,7 @@ int main(const int argc, char *const argv[])
        /* setup key */
        rc = keyctl_instantiate(key, keydata, datalen, 0);
        if (rc == -1) {
-               syslog(LOG_WARNING, "keyctl_instantiate: %s", strerror(errno));
+               syslog(LOG_ERR, "keyctl_instantiate: %s", strerror(errno));
                goto out;
        }
 
@@ -448,7 +456,7 @@ out:
        data_blob_free(&secblob);
        data_blob_free(&sess_key);
        SAFE_FREE(ccname);
-       SAFE_FREE(hostname);
+       SAFE_FREE(arg.hostname);
        SAFE_FREE(keydata);
        return rc;
 }