/*
- * $Id: uams_gss.c,v 1.12 2010-03-30 10:25:49 franklahm Exp $
- *
* Copyright (c) 1990,1993 Regents of The University of Michigan.
* Copyright (c) 1999 Adrian Sun (asun@u.washington.edu)
* Copyright (c) 2003 The Reed Institute
#include "config.h"
#endif /* HAVE_CONFIG_H */
-#include <stdio.h>
+#include <stdbool.h>
+#include <stdint.h>
#include <stdlib.h>
-#ifdef HAVE_UNISTD_H
-#include <unistd.h>
-#endif /* HAVE_UNISTD_H */
-
-/* STDC check */
-#if STDC_HEADERS
#include <string.h>
-#else /* STDC_HEADERS */
-#ifndef HAVE_STRCHR
-#define strchr index
-#define strrchr index
-#endif /* HAVE_STRCHR */
-char *strchr (), *strrchr ();
-#ifndef HAVE_MEMCPY
-#define memcpy(d,s,n) bcopy ((s), (d), (n))
-#define memmove(d,s,n) bcopy ((s), (d), (n))
-#endif /* ! HAVE_MEMCPY */
-#endif /* STDC_HEADERS */
-
-#include <errno.h>
+#include <arpa/inet.h>
+
#include <atalk/logger.h>
#include <atalk/afp.h>
#include <atalk/uam.h>
#include <atalk/util.h>
+#include <atalk/compat.h>
+#include <atalk/globals.h>
/* Kerberos includes */
-
-#if HAVE_GSSAPI_H
-#include <gssapi.h>
-#endif
-
-#if HAVE_GSSAPI_GSSAPI_H
+#ifdef HAVE_GSSAPI_GSSAPI_H
#include <gssapi/gssapi.h>
-#endif
-
-#if HAVE_GSSAPI_GSSAPI_GENERIC_H
-#include <gssapi/gssapi_generic.h>
-#endif
-
-#if HAVE_GSSAPI_GSSAPI_KRB5_H
-#include <gssapi/gssapi_krb5.h>
-#endif
+#else
+#include <gssapi.h>
+#endif // HAVE_GSSAPI_GSSAPI_H
-#if HAVE_COM_ERR_H
-#include <com_err.h>
-#endif
+#ifdef HAVE_KERBEROS
+#ifdef HAVE_KRB5_KRB5_H
+#include <krb5/krb5.h>
+#else
+#include <krb5.h>
+#endif /* HAVE_KRB5_KRB5_H */
+#endif /* HAVE_KERBEROS */
-/* We work around something I don't entirely understand... */
-/* BF: This is a Heimdal/MIT compatibility fix */
-#ifndef HAVE_GSS_C_NT_HOSTBASED_SERVICE
-#define GSS_C_NT_HOSTBASED_SERVICE gss_nt_service_name
-#endif
+#define LOG_UAMS(log_level, ...) \
+ LOG(log_level, logtype_uams, __VA_ARGS__)
-#ifdef MIN
-#undef MIN
-#endif
+#define LOG_LOGINCONT(log_level, ...) \
+ LOG_UAMS(log_level, "FPLoginCont: " __VA_ARGS__)
-#define MIN(a, b) ((a > b) ? b : a)
-
-static void log_status( char *s, OM_uint32 major_status,
- OM_uint32 minor_status )
+static void log_status(char *s,
+ OM_uint32 major_status,
+ OM_uint32 minor_status)
{
gss_buffer_desc msg = GSS_C_EMPTY_BUFFER;
OM_uint32 min_status, maj_status;
maj_status = gss_display_status( &min_status, major_status,
GSS_C_GSS_CODE, GSS_C_NULL_OID,
&maj_ctx, &msg );
- LOG(log_info, logtype_uams, "uams_gss.c :do_gss_auth: %s %.*s (error %s)", s,
- (int)msg.length, msg.value, strerror(errno));
+ LOG_UAMS(log_error, "%s %.*s (error %s)",
+ s, msg.length, msg.value, strerror(errno));
gss_release_buffer(&min_status, &msg);
if (!maj_ctx)
break;
}
+
while (1) {
maj_status = gss_display_status( &min_status, minor_status,
- GSS_C_MECH_CODE, GSS_C_NULL_OID, // gss_mech_krb5,
+ GSS_C_MECH_CODE, GSS_C_NULL_OID,
&min_ctx, &msg );
- LOG(log_info, logtype_uams, "uams_gss.c :do_gss_auth: %s %.*s (error %s)", s,
- (int)msg.length, msg.value, strerror(errno));
+ LOG_UAMS(log_error, "%s %.*s (error %s)",
+ s, msg.length, msg.value, strerror(errno));
gss_release_buffer(&min_status, &msg);
if (!min_ctx)
}
}
-
-static void log_ctx_flags( OM_uint32 flags )
+static void log_ctx_flags(OM_uint32 flags)
{
-#ifdef DEBUG1
if (flags & GSS_C_DELEG_FLAG)
- LOG(log_debug, logtype_uams, "uams_gss.c :context flag: GSS_C_DELEG_FLAG" );
+ LOG_LOGINCONT(log_debug, "context flag: GSS_C_DELEG_FLAG");
if (flags & GSS_C_MUTUAL_FLAG)
- LOG(log_debug, logtype_uams, "uams_gss.c :context flag: GSS_C_MUTUAL_FLAG" );
+ LOG_LOGINCONT(log_debug, "context flag: GSS_C_MUTUAL_FLAG");
if (flags & GSS_C_REPLAY_FLAG)
- LOG(log_debug, logtype_uams, "uams_gss.c :context flag: GSS_C_REPLAY_FLAG" );
+ LOG_LOGINCONT(log_debug, "context flag: GSS_C_REPLAY_FLAG");
if (flags & GSS_C_SEQUENCE_FLAG)
- LOG(log_debug, logtype_uams, "uams_gss.c :context flag: GSS_C_SEQUENCE_FLAG" );
+ LOG_LOGINCONT(log_debug, "context flag: GSS_C_SEQUENCE_FLAG");
if (flags & GSS_C_CONF_FLAG)
- LOG(log_debug, logtype_uams, "uams_gss.c :context flag: GSS_C_CONF_FLAG" );
+ LOG_LOGINCONT(log_debug, "context flag: GSS_C_CONF_FLAG");
if (flags & GSS_C_INTEG_FLAG)
- LOG(log_debug, logtype_uams, "uams_gss.c :context flag: GSS_C_INTEG_FLAG" );
-#endif
+ LOG_LOGINCONT(log_debug, "context flag: GSS_C_INTEG_FLAG");
}
-static void log_principal(gss_name_t server_name)
+static void log_service_name(gss_ctx_id_t context)
{
-#ifdef DEBUG1
OM_uint32 major_status = 0, minor_status = 0;
- gss_buffer_desc exported_name;
-
- /* Only for debugging purposes, check the gssapi internal representation */
- major_status = gss_export_name(&minor_status, server_name, &exported_name);
- LOG(log_debug, logtype_uams, "log_principal: exported server name is %s", (char*) exported_name.value);
- gss_release_buffer( &minor_status, &exported_name );
-#endif
-}
-
-/* get the principal from afpd and import it into server_name */
-static int get_afpd_principal(void *obj, gss_name_t *server_name)
-{
- OM_uint32 major_status = 0, minor_status = 0;
- char *realm, *fqdn, *service, *principal, *p;
- size_t realmlen=0, fqdnlen=0, servicelen=0;
- size_t principal_length;
- gss_buffer_desc s_princ_buffer;
-
- /* get all the required information from afpd */
- if (uam_afpserver_option(obj, UAM_OPTION_KRB5REALM, (void*) &realm, &realmlen) < 0)
- return 1;
- LOG(log_debug, logtype_uams, "get_afpd_principal: REALM: %s", realm);
-
- if (uam_afpserver_option(obj, UAM_OPTION_FQDN, (void*) &fqdn, &fqdnlen) < 0)
- return 1;
- LOG(log_debug, logtype_uams, "get_afpd_principal: fqdn: %s", fqdn);
-
- if (uam_afpserver_option(obj, UAM_OPTION_KRB5SERVICE, (void *)&service, &servicelen) < 0)
- return 1;
- LOG(log_debug, logtype_uams, "get_afpd_principal: service: %s", service);
-
- /* we need all the info, log error and return if one's missing */
- if (!service || !servicelen || !fqdn || !fqdnlen || !realm || !realmlen) {
- LOG(log_error, logtype_uams,
- "get_afpd_principal: could not retrieve required information from afpd.");
- return 1;
+ gss_name_t service_name;
+ gss_buffer_desc service_name_buffer;
+
+ major_status = gss_inquire_context(&minor_status,
+ context,
+ NULL,
+ &service_name,
+ NULL,
+ NULL,
+ NULL,
+ NULL,
+ NULL);
+ if (major_status != GSS_S_COMPLETE) {
+ log_status("gss_inquire_context", major_status, minor_status);
+ return;
}
- /* allocate memory to hold the temporary principal string */
- principal_length = servicelen + 1 + fqdnlen + 1 + realmlen + 1;
- if ( NULL == (principal = (char*) malloc( principal_length)) ) {
- LOG(log_error, logtype_uams,
- "get_afpd_principal: out of memory allocating %u bytes",
- principal_length);
- return 1;
- }
+ major_status = gss_display_name(&minor_status,
+ service_name,
+ &service_name_buffer,
+ NULL);
+ if (major_status == GSS_S_COMPLETE) {
+ LOG_LOGINCONT(log_debug,
+ "service principal is `%s'",
+ service_name_buffer.value);
- /*
- * Build the principal string.
- * Format: 'service/fqdn@realm'
- */
- strlcpy( principal, service, principal_length);
- strlcat( principal, "/", principal_length);
-
- /*
- * The fqdn we get from afpd may contain a port.
- * We need to strip the port from fqdn for principal.
- */
- p = strchr(fqdn, ':');
- if (p)
- *p = '\0';
- strlcat( principal, fqdn, principal_length);
- if (p)
- *p = ':';
- strlcat( principal, "@", principal_length);
- strlcat( principal, realm, principal_length);
-
- /*
- * Import our principal into the gssapi internal representation
- * stored in server_name.
- */
- s_princ_buffer.value = principal;
- s_princ_buffer.length = strlen( principal ) + 1;
+ gss_release_buffer(&minor_status, &service_name_buffer);
+ } else
+ log_status("gss_display_name", major_status, minor_status);
- LOG(log_debug, logtype_uams, "get_afpd_principal: importing principal `%s'", principal);
- major_status = gss_import_name( &minor_status,
- &s_princ_buffer,
- GSS_C_NO_OID,
- server_name );
-
- /*
- * Get rid of malloc'ed memmory.
- * Don't release the s_princ_buffer, we free principal instead.
- */
- free(principal);
-
- if (major_status != GSS_S_COMPLETE) {
- /* Importing our service principal failed, bail out. */
- log_status( "import_principal", major_status, minor_status );
- return 1;
- }
- return 0;
+ gss_release_name(&minor_status, &service_name);
}
-
-/* get the username */
-static int get_client_username(char *username, int ulen, gss_name_t *client_name)
+static int get_client_username(char *username,
+ int ulen,
+ gss_name_t *client_name)
{
OM_uint32 major_status = 0, minor_status = 0;
gss_buffer_desc client_name_buffer;
char *p;
- int namelen, ret=0;
+ int ret = 0;
/*
* To extract the unix username, use gss_display_name on client_name.
* the username before copying it to afpd's buffer.
*/
- major_status = gss_display_name( &minor_status, *client_name,
- &client_name_buffer, (gss_OID *)NULL );
+ major_status = gss_display_name(&minor_status,
+ *client_name,
+ &client_name_buffer,
+ NULL);
if (major_status != GSS_S_COMPLETE) {
- log_status( "display_name", major_status, minor_status );
+ log_status("gss_display_name", major_status, minor_status);
return 1;
}
- LOG(log_debug, logtype_uams, "get_client_username: user is `%s'", client_name_buffer.value);
+ LOG_LOGINCONT(log_debug,
+ "user principal is `%s'",
+ client_name_buffer.value);
/* chop off realm */
- p = strchr( client_name_buffer.value, '@' );
+ p = strchr(client_name_buffer.value, '@');
if (p)
*p = 0;
/* FIXME: chop off instance? */
- p = strchr( client_name_buffer.value, '/' );
+ p = strchr(client_name_buffer.value, '/');
if (p)
*p = 0;
/* check if this username fits into afpd's username buffer */
- namelen = strlen(client_name_buffer.value);
- if ( namelen >= ulen ) {
+ size_t cnblen = strlen(client_name_buffer.value);
+ if (cnblen >= ulen) {
/* The username is too long for afpd's buffer, bail out */
- LOG(log_error, logtype_uams,
- "get_client_username: username `%s' too long", client_name_buffer.value);
+ LOG_LOGINCONT(log_info,
+ "username `%s' too long (%d)",
+ client_name_buffer.value, cnblen);
ret = 1;
- }
- else {
+ } else {
/* copy stripped username to afpd's buffer */
strlcpy(username, client_name_buffer.value, ulen);
}
- /* we're done with client_name_buffer, release it */
- gss_release_buffer(&minor_status, &client_name_buffer );
+ gss_release_buffer(&minor_status, &client_name_buffer);
return ret;
}
/* wrap afpd's sessionkey */
static int wrap_sessionkey(gss_ctx_id_t context, struct session_info *sinfo)
{
- OM_uint32 status = 0;
- int ret=0;
+ OM_uint32 major_status = 0, minor_status = 0;
gss_buffer_desc sesskey_buff, wrap_buff;
+ int ret = 0;
/*
* gss_wrap afpd's session_key.
* with type 8 (kGetKerberosSessionKey) on FPGetSession.
* See AFP 3.1 specs, page 77.
*/
-
sesskey_buff.value = sinfo->sessionkey;
sesskey_buff.length = sinfo->sessionkey_len;
- /* gss_wrap the session key with the default machanism.
+ /* gss_wrap the session key with the default mechanism.
Require both confidentiality and integrity services */
- gss_wrap (&status, context, 1, GSS_C_QOP_DEFAULT, &sesskey_buff, NULL, &wrap_buff);
+ major_status = gss_wrap(&minor_status,
+ context,
+ true,
+ GSS_C_QOP_DEFAULT,
+ &sesskey_buff,
+ NULL,
+ &wrap_buff);
- if ( status != GSS_S_COMPLETE) {
- LOG(log_error, logtype_uams, "wrap_sessionkey: failed to gss_wrap sessionkey");
- log_status( "GSS wrap", 0, status );
+ if (major_status != GSS_S_COMPLETE) {
+ log_status("gss_wrap", major_status, minor_status);
return 1;
}
/* store the wrapped session key in afpd's session_info struct */
- if ( NULL == (sinfo->cryptedkey = malloc ( wrap_buff.length )) ) {
- LOG(log_error, logtype_uams,
- "wrap_sessionkey: out of memory tyring to allocate %u bytes",
- wrap_buff.length);
+ if (NULL == (sinfo->cryptedkey = malloc(wrap_buff.length))) {
+ LOG_UAMS(log_error,
+ "wrap_sessionkey: out of memory tyring to allocate %u bytes",
+ wrap_buff.length);
ret = 1;
} else {
/* cryptedkey is binary data */
- memcpy (sinfo->cryptedkey, wrap_buff.value, wrap_buff.length);
+ memcpy(sinfo->cryptedkey, wrap_buff.value, wrap_buff.length);
sinfo->cryptedkey_len = wrap_buff.length;
}
/* we're done with buffer, release */
- gss_release_buffer( &status, &wrap_buff );
+ gss_release_buffer(&minor_status, &wrap_buff);
return ret;
}
-/*-------------*/
-static int acquire_credentials (gss_name_t *server_name, gss_cred_id_t *server_creds)
+static int accept_sec_context(gss_ctx_id_t *context,
+ gss_buffer_desc *ticket_buffer,
+ gss_name_t *client_name,
+ gss_buffer_desc *authenticator_buff)
{
- OM_uint32 major_status = 0, minor_status = 0;
- char *envp;
-
- if ((envp = getenv("KRB5_KTNAME")))
- LOG(log_debug, logtype_uams,
- "acquire credentials: acquiring credentials (uid = %d, keytab = %s)",
- (int)geteuid(), envp);
- else
- LOG(log_debug, logtype_uams,
- "acquire credentials: acquiring credentials (uid = %d) - $KRB5_KTNAME not found in env",
- (int)geteuid());
-
- /*
- * Acquire credentials usable for accepting context negotiations.
- * Credentials are for server_name, have an indefinite lifetime,
- * have no specific mechanisms, are to be used for accepting context
- * negotiations and are to be placed in server_creds.
- * We don't care about the mechanisms or about the time for which they are valid.
- */
- major_status = gss_acquire_cred( &minor_status, *server_name,
- GSS_C_INDEFINITE, GSS_C_NO_OID_SET, GSS_C_ACCEPT,
- server_creds, NULL, NULL );
-
- if (major_status != GSS_S_COMPLETE) {
- log_status( "acquire_cred", major_status, minor_status );
- return 1;
- }
-
- return 0;
-}
-
-/*-------------*/
-static int accept_sec_context (gss_ctx_id_t *context, gss_cred_id_t server_creds,
- gss_buffer_desc *ticket_buffer, gss_name_t *client_name,
- gss_buffer_desc *authenticator_buff)
-{
- OM_uint32 major_status = 0, minor_status = 0, ret_flags;
+ OM_uint32 major_status = 0, minor_status = 0, flags = 0;
/* Initialize autheticator buffer. */
authenticator_buff->length = 0;
authenticator_buff->value = NULL;
- LOG(log_debug, logtype_uams, "accept_context: accepting context (ticketlen: %u)",
- ticket_buffer->length);
+ LOG_LOGINCONT(log_debug,
+ "accepting context (ticketlen: %u)",
+ ticket_buffer->length);
/*
- * Try to accept the secondary context using the tocken in ticket_buffer.
- * We don't care about the mechanisms used, nor for the time.
+ * Try to accept the secondary context using the token in ticket_buffer.
+ * We don't care about the principals or mechanisms used, nor for the time.
* We don't act as a proxy either.
*/
- major_status = gss_accept_sec_context( &minor_status, context,
- server_creds, ticket_buffer, GSS_C_NO_CHANNEL_BINDINGS,
- client_name, NULL, authenticator_buff,
- &ret_flags, NULL, NULL );
+ major_status = gss_accept_sec_context(&minor_status,
+ context,
+ GSS_C_NO_CREDENTIAL,
+ ticket_buffer,
+ GSS_C_NO_CHANNEL_BINDINGS,
+ client_name,
+ NULL,
+ authenticator_buff,
+ &flags,
+ NULL,
+ NULL);
if (major_status != GSS_S_COMPLETE) {
- log_status( "accept_sec_context", major_status, minor_status );
+ log_status("gss_accept_sec_context", major_status, minor_status);
return 1;
}
- log_ctx_flags( ret_flags );
+
+ log_ctx_flags(flags);
return 0;
}
-
-/* return 0 on success */
-static int do_gss_auth(void *obj, char *ibuf, int ticket_len,
- char *rbuf, int *rbuflen, char *username, int ulen,
+static int do_gss_auth(void *obj,
+ char *ibuf, size_t ibuflen,
+ char *rbuf, int *rbuflen,
+ char *username, size_t ulen,
struct session_info *sinfo )
{
OM_uint32 status = 0;
- gss_name_t server_name, client_name;
- gss_cred_id_t server_creds;
- gss_ctx_id_t context_handle = GSS_C_NO_CONTEXT;
+ gss_name_t client_name;
+ gss_ctx_id_t context = GSS_C_NO_CONTEXT;
gss_buffer_desc ticket_buffer, authenticator_buff;
int ret = 0;
- /* import our principal name from afpd */
- if (get_afpd_principal(obj, &server_name) != 0) {
- return 1;
- }
- log_principal(server_name);
-
- /* Now we have to acquire our credentials */
- if ((ret = acquire_credentials (&server_name, &server_creds)))
- goto cleanup_vars;
-
/*
* Try to accept the secondary context, using the ticket/token the
* client sent us. Ticket is stored at current ibuf position.
* Don't try to release ticket_buffer later, it points into ibuf!
*/
- ticket_buffer.length = ticket_len;
+ ticket_buffer.length = ibuflen;
ticket_buffer.value = ibuf;
- ret = accept_sec_context (&context_handle, server_creds, &ticket_buffer,
- &client_name, &authenticator_buff);
+ if ((ret = accept_sec_context(&context,
+ &ticket_buffer,
+ &client_name,
+ &authenticator_buff)))
+ return ret;
+ log_service_name(context);
- if (!ret) {
- /* We succesfully acquired the secondary context, now get the
- username for afpd and gss_wrap the sessionkey */
- if ( 0 == (ret = get_client_username(username, ulen, &client_name)) ) {
- ret = wrap_sessionkey(context_handle, sinfo);
- }
-
- if (!ret) {
- /* FIXME: Is copying the authenticator really necessary?
- Where is this documented? */
- u_int16_t auth_len = htons( authenticator_buff.length );
+ /* We succesfully acquired the secondary context, now get the
+ username for afpd and gss_wrap the sessionkey */
+ if ((ret = get_client_username(username, ulen, &client_name)))
+ goto cleanup_client_name;
- /* copy the authenticator length into the reply buffer */
- memcpy( rbuf, &auth_len, sizeof(auth_len) );
- *rbuflen += sizeof(auth_len);
- rbuf += sizeof(auth_len);
+ if ((ret = wrap_sessionkey(context, sinfo)))
+ goto cleanup_client_name;
- /* copy the authenticator value into the reply buffer */
- memcpy( rbuf, authenticator_buff.value, authenticator_buff.length );
- *rbuflen += authenticator_buff.length;
- }
+ /* Authenticated, construct the reply using:
+ * authenticator length (uint16_t)
+ * authenticator
+ */
+ /* copy the authenticator length into the reply buffer */
+ uint16_t auth_len = htons(authenticator_buff.length);
+ memcpy(rbuf, &auth_len, sizeof(auth_len));
+ *rbuflen += sizeof(auth_len);
+ rbuf += sizeof(auth_len);
- /* Clean up after ourselves */
- gss_release_name( &status, &client_name );
- if ( authenticator_buff.value)
- gss_release_buffer( &status, &authenticator_buff );
+ /* copy the authenticator value into the reply buffer */
+ memcpy(rbuf, authenticator_buff.value, authenticator_buff.length);
+ *rbuflen += authenticator_buff.length;
- gss_delete_sec_context( &status, &context_handle, NULL );
- }
- gss_release_cred( &status, &server_creds );
-
-cleanup_vars:
- gss_release_name( &status, &server_name );
+cleanup_client_name:
+ gss_release_name(&status, &client_name);
+ gss_release_buffer(&status, &authenticator_buff);
+ gss_delete_sec_context(&status, &context, NULL);
return ret;
}
/* -------------------------- */
-static int gss_login(void *obj, struct passwd **uam_pwd,
+
+/*
+ * For the gss uam, this function only needs to return a two-byte
+ * login-session id. None of the data provided by the client up to this
+ * point is trustworthy as we'll have a signed ticket to parse in logincont.
+ */
+static int gss_login(void *obj,
+ struct passwd **uam_pwd,
char *ibuf, size_t ibuflen,
char *rbuf, size_t *rbuflen)
{
-
- u_int16_t temp16;
-
*rbuflen = 0;
/* The reply contains a two-byte ID value - note
* that Apple's implementation seems to always return 1 as well
*/
- temp16 = htons( 1 );
+ uint16_t temp16 = htons(1);
memcpy(rbuf, &temp16, sizeof(temp16));
*rbuflen += sizeof(temp16);
+
return AFPERR_AUTHCONT;
}
-static int gss_logincont(void *obj, struct passwd **uam_pwd,
+static int gss_logincont(void *obj,
+ struct passwd **uam_pwd,
char *ibuf, size_t ibuflen,
char *rbuf, size_t *rbuflen)
{
struct passwd *pwd = NULL;
- u_int16_t login_id;
+ uint16_t login_id;
char *username;
- u_int16_t ticket_len;
+ uint16_t ticket_len;
char *p;
int rblen;
size_t userlen;
/* Apple's AFP 3.1 documentation specifies that this command
* takes the following format:
* pad (byte)
- * id returned in LoginExt response (u_int16_t)
- * username (format unspecified) padded, when necessary, to end on an even boundary
- * ticket length (u_int16_t)
+ * id returned in LoginExt response (uint16_t)
+ * username (format unspecified)
+ * padded, when necessary, to end on an even boundary
+ * ticket length (uint16_t)
* ticket
*/
* format of this request is as follows:
* pad (byte) [consumed before login_ext is called]
* ?? (byte) - always observed to be 0
- * id returned in LoginExt response (u_int16_t)
+ * id returned in LoginExt response (uint16_t)
* username, encoding unspecified, null terminated C string,
* padded when the terminating null is an even numbered byte.
* The packet is formated such that the username begins on an
* odd numbered byte. Eg if the username is 3 characters and the
* terminating null makes 4, expect to pad the the result.
* The encoding of this string is unknown.
- * ticket length (u_int16_t)
+ * ticket length (uint16_t)
* ticket
*/
rblen = *rbuflen = 0;
if (ibuflen < 1 +sizeof(login_id)) {
- LOG(log_info, logtype_uams, "uams_gss.c :LoginCont: received incomplete packet");
+ LOG_LOGINCONT(log_info, "received incomplete packet");
return AFPERR_PARAM;
}
ibuf++, ibuflen--; /* ?? */
/* 2 byte ID from LoginExt -- always '00 01' in this implementation */
- memcpy( &login_id, ibuf, sizeof(login_id) );
+ memcpy(&login_id, ibuf, sizeof(login_id));
ibuf += sizeof(login_id), ibuflen -= sizeof(login_id);
- login_id = ntohs( login_id );
+ login_id = ntohs(login_id);
/* get the username buffer from apfd */
- if (uam_afpserver_option(obj, UAM_OPTION_USERNAME, (void *) &username, &userlen) < 0)
+ if (uam_afpserver_option(obj, UAM_OPTION_USERNAME, &username, &userlen) < 0)
return AFPERR_MISC;
/* get the session_info structure from afpd. We need the session key */
- if (uam_afpserver_option(obj, UAM_OPTION_SESSIONINFO, (void *)&sinfo, NULL) < 0)
+ if (uam_afpserver_option(obj, UAM_OPTION_SESSIONINFO, &sinfo, NULL) < 0)
return AFPERR_MISC;
if (sinfo->sessionkey == NULL || sinfo->sessionkey_len == 0) {
/* Should never happen. Most likely way too old afpd version */
- LOG(log_info, logtype_uams, "internal error: afpd's sessionkey not set");
+ LOG_LOGINCONT(log_error, "internal error: afpd's sessionkey not set");
return AFPERR_MISC;
}
/* We skip past the 'username' parameter because all that matters is the ticket */
p = ibuf;
- while( *ibuf && ibuflen ) { ibuf++, ibuflen--; }
+ while ( *ibuf && ibuflen ) { ibuf++, ibuflen--; }
if (ibuflen < 4) {
- LOG(log_info, logtype_uams, "uams_gss.c :LoginCont: user is %s, no ticket", p);
+ LOG_LOGINCONT(log_info, "user is %s, no ticket", p);
return AFPERR_PARAM;
}
if ((ibuf - p + 1) % 2) ibuf++, ibuflen--; /* deal with potential padding */
- LOG(log_debug, logtype_uams, "uams_gss.c :LoginCont: client thinks user is %s", p);
+ LOG_LOGINCONT(log_debug, "client thinks user is %s", p);
/* get the length of the ticket the client sends us */
memcpy(&ticket_len, ibuf, sizeof(ticket_len));
ibuf += sizeof(ticket_len); ibuflen -= sizeof(ticket_len);
- ticket_len = ntohs( ticket_len );
+ ticket_len = ntohs(ticket_len);
/* a little bounds checking */
if (ticket_len > ibuflen) {
- LOG(log_info, logtype_uams,
- "uams_gss.c :LoginCont: invalid ticket length (%u > %u)", ticket_len, ibuflen);
+ LOG_LOGINCONT(log_info,
+ "invalid ticket length (%u > %u)",
+ ticket_len, ibuflen);
return AFPERR_PARAM;
}
/* now try to authenticate */
- if (!do_gss_auth(obj, ibuf, ticket_len, rbuf, &rblen, username, userlen, sinfo)) {
- /* We use the username we got back from the gssapi client_name.
- Should we compare this to the username the client sent in the clear?
- We know the character encoding of the cleartext username (UTF8), what
- encoding is the gssapi name in? */
- if((pwd = uam_getname( obj, username, userlen )) == NULL) {
- LOG(log_info, logtype_uams, "uam_getname() failed for %s", username);
- return AFPERR_NOTAUTH;
- }
- if (uam_checkuser(pwd) < 0) {
- LOG(log_info, logtype_uams, "%s not a valid user", username);
- return AFPERR_NOTAUTH;
- }
- *rbuflen = rblen;
- *uam_pwd = pwd;
- return AFP_OK;
- } else {
- LOG(log_info, logtype_uams, "do_gss_auth failed" );
+ if (do_gss_auth(obj, ibuf, ticket_len, rbuf, &rblen, username, userlen, sinfo)) {
+ LOG_LOGINCONT(log_info, "do_gss_auth() failed" );
*rbuflen = 0;
return AFPERR_MISC;
}
+
+ /* We use the username we got back from the gssapi client_name.
+ Should we compare this to the username the client sent in the clear?
+ We know the character encoding of the cleartext username (UTF8), what
+ encoding is the gssapi name in? */
+ if ((pwd = uam_getname( obj, username, userlen )) == NULL) {
+ LOG_LOGINCONT(log_info, "uam_getname() failed for %s", username);
+ return AFPERR_NOTAUTH;
+ }
+ if (uam_checkuser(pwd) < 0) {
+ LOG_LOGINCONT(log_info, "`%s'' not a valid user", username);
+ return AFPERR_NOTAUTH;
+ }
+
+ *rbuflen = rblen;
+ *uam_pwd = pwd;
+ return AFP_OK;
}
-/*
- * For the krb5 uam, this function only needs to return a two-byte
- * login-session id. None of the data provided by the client up to this
- * point is trustworthy as we'll have a signed ticket to parse in logincont.
- */
-static int gss_login_ext(void *obj, char *uname, struct passwd **uam_pwd,
+/* logout */
+static void gss_logout() {
+}
+
+static int gss_login_ext(void *obj,
+ char *uname,
+ struct passwd **uam_pwd,
char *ibuf, size_t ibuflen,
char *rbuf, size_t *rbuflen)
{
- u_int16_t temp16;
+ return gss_login(obj, uam_pwd, ibuf, ibuflen, rbuf, rbuflen);
+}
- *rbuflen = 0;
+static int set_principal(AFPObj *obj, char *principal)
+{
+ size_t len = strlen(principal);
- /* The reply contains a two-byte ID value - note
- * that Apple's implementation seems to always return 1 as well
- */
- temp16 = htons( 1 );
- memcpy(rbuf, &temp16, sizeof(temp16));
- *rbuflen += sizeof(temp16);
- return AFPERR_AUTHCONT;
+ if (len > 255) {
+ LOG(log_error, logtype_afpd, "set_principal: principal '%s' too long (max=255)", principal, len);
+ return -1;
+ }
+
+ /* We store: 1 byte number principals (1) + 1 byte principal name length + zero terminated principal */
+ if ((obj->options.k5principal = malloc(len + 3)) == NULL) {
+ LOG(log_error, logtype_afpd, "set_principal: OOM");
+ return -1;
+ }
+
+ LOG(log_info, logtype_afpd, "Using AFP Kerberos service principal name: %s", principal);
+
+ obj->options.k5principal[0] = 1;
+ obj->options.k5principal[1] = (unsigned char)len;
+ obj->options.k5principal_buflen = len + 2;
+ strncpy(obj->options.k5principal + 2, principal, len);
+
+ return 0;
}
-/* logout */
-static void gss_logout() {
+static int gss_create_principal(AFPObj *obj)
+{
+ int rv = -1;
+#ifdef HAVE_KERBEROS
+ krb5_context context;
+ krb5_error_code ret;
+ const char *error_msg;
+ krb5_keytab keytab;
+ krb5_keytab_entry entry;
+ krb5_principal service_principal;
+ char *principal;
+ krb5_kt_cursor cursor;
+
+ if (krb5_init_context(&context)) {
+ LOG(log_error, logtype_afpd, "gss_create_principal: failed to intialize a krb5_context");
+ goto exit;
+ }
+ if ((ret = krb5_kt_default(context, &keytab)))
+ goto krb5_error;
+
+ if (obj->options.k5service && obj->options.fqdn && obj->options.k5realm) {
+ LOG(log_debug, logtype_afpd, "gss_create_principal: using service principal specified in options");
+
+ if ((ret = krb5_build_principal(context,
+ &service_principal,
+ strlen(obj->options.k5realm),
+ obj->options.k5realm,
+ obj->options.k5service,
+ obj->options.fqdn,
+ NULL)))
+ goto krb5_error;
+
+ if ((ret = krb5_kt_get_entry(context,
+ keytab,
+ service_principal,
+ 0, // kvno - wildcard
+ 0, // enctype - wildcard
+ &entry)) == KRB5_KT_NOTFOUND) {
+ krb5_unparse_name(context, service_principal, &principal);
+ LOG(log_error, logtype_afpd, "gss_create_principal: specified service principal '%s' not found in keytab", principal);
+#ifdef HAVE_KRB5_FREE_UNPARSED_NAME
+ krb5_free_unparsed_name(context, principal);
+#else
+ krb5_xfree(principal);
+#endif
+ goto krb5_cleanup;
+ }
+ krb5_free_principal(context, service_principal);
+ if (ret)
+ goto krb5_error;
+ } else {
+ LOG(log_debug, logtype_afpd, "gss_create_principal: using first entry from keytab as service principal");
+ if ((ret = krb5_kt_start_seq_get(context, keytab, &cursor)))
+ goto krb5_error;
+ ret = krb5_kt_next_entry(context, keytab, &entry, &cursor);
+ krb5_kt_end_seq_get(context, keytab, &cursor);
+ if (ret)
+ goto krb5_error;
+ }
+
+ krb5_unparse_name(context, entry.principal, &principal);
+#ifdef HAVE_KRB5_FREE_KEYTAB_ENTRY_CONTENTS
+ krb5_free_keytab_entry_contents(context, &entry);
+#elif defined(HAVE_KRB5_KT_FREE_ENTRY)
+ krb5_kt_free_entry(context, &entry);
+#endif
+ set_principal(obj, principal);
+ free(principal);
+ rv = 0;
+ goto krb5_cleanup;
+
+krb5_error:
+ if (ret) {
+ error_msg = krb5_get_error_message(context, ret);
+ LOG(log_note, logtype_afpd, "Can't get principal from default keytab: %s",
+ (char *)error_msg);
+#ifdef HAVE_KRB5_FREE_ERROR_MESSAGE
+ krb5_free_error_message(context, error_msg);
+#else
+ krb5_xfree(error_msg);
+#endif
+ }
+
+krb5_cleanup:
+ krb5_kt_close(context, keytab);
+ krb5_free_context(context);
+
+#else /* ! HAVE_KERBEROS */
+ if (!obj->options.k5service || !obj->options.fqdn || !obj->options.k5realm)
+ goto exit;
+
+ char principal[255];
+ size_t len = snprintf(principal, sizeof(principal), "%s/%s@%s",
+ obj->options.k5service, obj->options.fqdn, obj->options.k5realm);
+ (void)set_principal(obj, principal);
+ rv = 0;
+#endif /* HAVE_KERBEROS */
+
+exit:
+ return rv;
}
-int uam_setup(const char *path)
+static int uam_setup(void *handle, const char *path)
{
- if (uam_register(UAM_SERVER_LOGIN_EXT, path, "Client Krb v2",
- gss_login, gss_logincont, gss_logout, gss_login_ext) < 0)
- if (uam_register(UAM_SERVER_LOGIN, path, "Client Krb v2",
- gss_login, gss_logincont, gss_logout) < 0)
- return -1;
+ AFPObj *obj = (AFPObj *)handle;
+ if (gss_create_principal(obj) != 0)
+ return -1;
- return 0;
+ return uam_register(UAM_SERVER_LOGIN_EXT, path, "Client Krb v2",
+ gss_login, gss_logincont, gss_logout, gss_login_ext);
}
static void uam_cleanup(void)
UAM_MODULE_EXPORT struct uam_export uams_gss = {
UAM_MODULE_SERVER,
UAM_MODULE_VERSION,
- uam_setup, uam_cleanup
+ uam_setup,
+ uam_cleanup
};