/*
* CIFS user-space helper.
* Copyright (C) Igor Mammedov (niallain@gmail.com) 2007
+* Copyright (C) Jeff Layton (jlayton@redhat.com) 2009
*
* Used by /sbin/request-key for handling
* cifs upcall for kerberos authorization of access to share and
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
+ * in the context of that process. On error, just return NULL.
+ */
+static char *
+get_krb5_ccname(pid_t pid)
+{
+ int fd;
+ ssize_t len, left;
+
+ /*
+ * FIXME: sysconf for ARG_MAX instead? Kernel seems to be limited to a
+ * page however, so it may not matter.
+ */
+ char buf[4096];
+ char *p, *value = NULL;
+
+ buf[4095] = '\0';
+ snprintf(buf, 4095, "/proc/%d/environ", pid);
+ fd = open(buf, O_RDONLY);
+ 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) {
+ syslog(LOG_DEBUG, "%s: unable to read from /proc/%d/environ: "
+ "%d", __func__, pid, errno);
+ return NULL;
+ }
+
+ left = len;
+ p = buf;
+
+ /* can't have valid KRB5CCNAME if there are < 13 bytes left */
+ while (left > 12) {
+ if (strncmp("KRB5CCNAME=", p, 11)) {
+ p += strnlen(p, left);
+ ++p;
+ left = buf + len - p;
+ continue;
+ }
+ p += 11;
+ left -= 11;
+ value = SMB_STRNDUP(p, left);
+ break;
+ }
+ syslog(LOG_DEBUG, "%s: KRB5CCNAME=%s", __func__,
+ value ? value : "(null)");
+ return value;
+}
/*
* Prepares AP-REQ data for mechToken and gets session key
* 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)
+handle_krb5_mech(const char *oid, const char *principal, DATA_BLOB *secblob,
+ DATA_BLOB *sess_key, const char *ccname)
{
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, NULL, NULL);
+ 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);
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_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)
+decode_key_description(const char *desc, struct decoded_args *arg)
{
int retval = 0;
char *pos;
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? */
} else if (strncmp(tkn, "ipv6=", 5) == 0) {
/* BB: do we need it if we have hostname already? */
+ } else if (strncmp(tkn, "pid=", 4) == 0) {
+ errno = 0;
+ arg->pid = strtol(tkn + 4, NULL, 0);
+ if (errno != 0) {
+ syslog(LOG_ERR, "Invalid pid format: %s",
+ strerror(errno));
+ return 1;
+ } else {
+ retval |= DKD_HAVE_PID;
+ }
} 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 {
}
} 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 {
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;
}
/* 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;
}
/* 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;
}
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);
}
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;
- int kernel_upcall_version = 0;
int c, use_cifs_service_prefix = 0;
- char *buf, *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;
- }
}
}
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, §ype,
- &hostname, &uid);
+ 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(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;
}
}
- /* BB: someday upcall SPNEGO blob could be checked here to decide
- * what mech to use */
-
// 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);
- 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 =
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;
/* 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;
}
keyctl_negate(key, 1, KEY_REQKEY_DEFL_DEFAULT);
data_blob_free(&secblob);
data_blob_free(&sess_key);
- SAFE_FREE(hostname);
+ SAFE_FREE(ccname);
+ SAFE_FREE(arg.hostname);
SAFE_FREE(keydata);
return rc;
}
git.samba.org / sfrench / samba-autobuild / .git / blobdiff