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/*
svc_in_gssd_proc.c
Copyright (c) 2000 The Regents of the University of Michigan.
All rights reserved.
Copyright (c) 2002 Bruce Fields <bfields@UMICH.EDU>
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
3. Neither the name of the University nor the names of its
contributors may be used to endorse or promote products derived
from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/param.h>
#include <sys/stat.h>
#include <rpc/rpc.h>
#include <pwd.h>
#include <stdio.h>
#include <unistd.h>
#include <ctype.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <nfsidmap.h>
#include "svcgssd.h"
#include "gss_util.h"
#include "err_util.h"
#include "context.h"
#include "cacheio.h"
/* XXX: ? */
#ifndef NGROUPS
#define NGROUPS 32
#endif
extern char * mech2file(gss_OID mech);
#define SVCGSSD_CONTEXT_CHANNEL "/proc/net/rpc/auth.rpcsec.context/channel"
#define SVCGSSD_INIT_CHANNEL "/proc/net/rpc/auth.rpcsec.init/channel"
struct svc_cred {
uid_t cr_uid;
gid_t cr_gid;
int cr_ngroups;
gid_t cr_groups[NGROUPS];
};
static int
do_svc_downcall(gss_buffer_desc *out_handle, struct svc_cred *cred,
gss_OID mech, gss_buffer_desc *context_token)
{
FILE *f;
int i;
char *fname = NULL;
printerr(1, "doing downcall\n");
if ((fname = mech2file(mech)) == NULL)
goto out_err;
f = fopen(SVCGSSD_CONTEXT_CHANNEL, "w");
if (f == NULL) {
printerr(0, "WARNING: unable to open downcall channel "
"%s: %s\n",
SVCGSSD_CONTEXT_CHANNEL, strerror(errno));
goto out_err;
}
qword_printhex(f, out_handle->value, out_handle->length);
/* XXX are types OK for the rest of this? */
qword_printint(f, 0x7fffffff); /*XXX need a better timeout */
qword_printint(f, cred->cr_uid);
qword_printint(f, cred->cr_gid);
qword_printint(f, cred->cr_ngroups);
for (i=0; i < cred->cr_ngroups; i++)
qword_printint(f, cred->cr_groups[i]);
qword_print(f, fname);
qword_printhex(f, context_token->value, context_token->length);
qword_eol(f);
fclose(f);
return 0;
out_err:
printerr(0, "WARNING: downcall failed\n");
return -1;
}
struct gss_verifier {
u_int32_t flav;
gss_buffer_desc body;
};
#define RPCSEC_GSS_SEQ_WIN 5
static int
send_response(FILE *f, gss_buffer_desc *in_handle, gss_buffer_desc *in_token,
u_int32_t maj_stat, u_int32_t min_stat,
gss_buffer_desc *out_handle, gss_buffer_desc *out_token)
{
char buf[2 * 4096];
char *bp = buf;
int blen = sizeof(buf);
/* XXXARG: */
int g;
printerr(1, "sending null reply\n");
qword_addhex(&bp, &blen, in_handle->value, in_handle->length);
qword_addhex(&bp, &blen, in_token->value, in_token->length);
qword_addint(&bp, &blen, 0x7fffffff); /*XXX need a better timeout */
qword_addint(&bp, &blen, maj_stat);
qword_addint(&bp, &blen, min_stat);
qword_addhex(&bp, &blen, out_handle->value, out_handle->length);
qword_addhex(&bp, &blen, out_token->value, out_token->length);
qword_addeol(&bp, &blen);
if (blen <= 0) {
printerr(0, "WARNING: send_respsonse: message too long\n");
return -1;
}
g = open(SVCGSSD_INIT_CHANNEL, O_WRONLY);
if (g == -1) {
printerr(0, "WARNING: open %s failed: %s\n",
SVCGSSD_INIT_CHANNEL, strerror(errno));
return -1;
}
*bp = '\0';
printerr(1, "writing message: %s", buf);
if (write(g, buf, bp - buf) == -1) {
printerr(0, "WARNING: failed to write message\n");
close(g);
return -1;
}
close(g);
return 0;
}
#define rpc_auth_ok 0
#define rpc_autherr_badcred 1
#define rpc_autherr_rejectedcred 2
#define rpc_autherr_badverf 3
#define rpc_autherr_rejectedverf 4
#define rpc_autherr_tooweak 5
#define rpcsec_gsserr_credproblem 13
#define rpcsec_gsserr_ctxproblem 14
static int
get_ids(gss_name_t client_name, gss_OID mech, struct svc_cred *cred)
{
u_int32_t maj_stat, min_stat;
gss_buffer_desc name;
char *sname;
int res = -1;
uid_t uid, gid;
gss_OID name_type;
char *secname;
maj_stat = gss_display_name(&min_stat, client_name, &name, &name_type);
if (maj_stat != GSS_S_COMPLETE)
goto out;
if (!(sname = calloc(name.length + 1, 1)))
goto out;
memcpy(sname, name.value, name.length);
printerr(1, "sname = %s\n", sname);
res = -EINVAL;
if ((secname = mech2file(mech)) == NULL)
goto out_free;
nfs4_init_name_mapping(NULL); /* XXX: should only do this once */
res = nfs4_gss_princ_to_ids(secname, sname, &uid, &gid);
if (res < 0)
goto out_free;
cred->cr_uid = uid;
cred->cr_gid = gid;
/*XXX: want add_supplementary_groups(secname, sname, cred)? */
cred->cr_ngroups = 0;
res = 0;
out_free:
free(sname);
out:
if (res)
printerr(0, "WARNING: get_uid failed\n");
return res;
}
void
print_hexl(int pri, unsigned char *cp, int length)
{
int i, j, jm;
unsigned char c;
printerr(pri, "length %d\n",length);
printerr(pri, "\n");
for (i = 0; i < length; i += 0x10) {
printerr(pri, " %04x: ", (u_int)i);
jm = length - i;
jm = jm > 16 ? 16 : jm;
for (j = 0; j < jm; j++) {
if ((j % 2) == 1)
printerr(pri,"%02x ", (u_int)cp[i+j]);
else
printerr(pri,"%02x", (u_int)cp[i+j]);
}
for (; j < 16; j++) {
if ((j % 2) == 1)
printerr(pri," ");
else
printerr(pri," ");
}
printerr(pri," ");
for (j = 0; j < jm; j++) {
c = cp[i+j];
c = isprint(c) ? c : '.';
printerr(pri,"%c", c);
}
printerr(pri,"\n");
}
}
void
handle_nullreq(FILE *f) {
/* XXX initialize to a random integer to reduce chances of unnecessary
* invalidation of existing ctx's on restarting svcgssd. */
static u_int32_t handle_seq = 0;
char in_tok_buf[1023];
char in_handle_buf[15];
char out_handle_buf[15];
gss_buffer_desc in_tok = {.value = in_tok_buf},
out_tok = {.value = NULL},
in_handle = {.value = in_handle_buf},
out_handle = {.value = out_handle_buf},
ctx_token = {.value = NULL},
/* XXX isn't there a define for this?: */
null_token = {.value = NULL};
u_int32_t ret_flags;
gss_ctx_id_t ctx = GSS_C_NO_CONTEXT;
gss_name_t client_name;
gss_OID mech;
u_int32_t maj_stat = GSS_S_FAILURE, min_stat = 0;
struct svc_cred cred;
static char *lbuf = NULL;
static int lbuflen = 0;
static char *cp;
printerr(1, "handling null request\n");
if (readline(fileno(f), &lbuf, &lbuflen) != 1) {
printerr(0, "WARNING: handle_nullreq: "
"failed reading request\n");
return;
}
cp = lbuf;
in_handle.length
= qword_get(&cp, in_handle.value, sizeof(in_handle_buf));
printerr(2, "in_handle: \n");
print_hexl(2, in_handle.value, in_handle.length);
handle_seq++;
out_handle.length = sizeof(handle_seq);
memcpy(out_handle.value, &handle_seq, sizeof(handle_seq));
in_tok.length = qword_get(&cp, in_tok.value, sizeof(in_tok_buf));
printerr(2, "in_tok: \n");
print_hexl(2, in_tok.value, in_tok.length);
if (in_tok.length < 0) {
printerr(0, "WARNING: handle_nullreq: "
"failed parsing request\n");
goto out_err;
}
if (in_handle.length != 0) { /* CONTINUE_INIT case */
printerr(0, "WARNING: handle_nullreq: "
"CONTINUE_INIT unsupported\n");
send_response(f, &in_handle, &in_tok, -1, -1, &null_token,
&null_token);
goto out_err;
}
maj_stat = gss_accept_sec_context(&min_stat, &ctx, gssd_creds,
&in_tok, GSS_C_NO_CHANNEL_BINDINGS, &client_name,
&mech, &out_tok, &ret_flags, NULL, NULL);
if (maj_stat != GSS_S_COMPLETE) {
printerr(0, "WARNING: gss_accept_sec_context failed\n");
pgsserr("handle_nullreq: gss_accept_sec_context",
maj_stat, min_stat, mech);
send_response(f, &in_handle, &in_tok, maj_stat, min_stat,
&null_token, &null_token);
goto out_err;
}
if (get_ids(client_name, mech, &cred)) {
printerr(0, "WARNING: handle_nullreq: get_uid failed\n");
send_response(f, &in_handle, &in_tok, GSS_S_BAD_NAME /* XXX? */,
0, &null_token, &null_token);
goto out_err;
}
/* kernel needs ctx to calculate verifier on null response, so
* must give it context before doing null call: */
if (serialize_context_for_kernel(ctx, &ctx_token)) {
printerr(0, "WARNING: handle_nullreq: "
"serialize_context_for_kernel failed\n");
send_response(f, &in_handle, &in_tok, -1, /* XXX? */
0, &null_token, &null_token);
goto out_err;
}
do_svc_downcall(&out_handle, &cred, mech, &ctx_token);
send_response(f, &in_handle, &in_tok, maj_stat, min_stat,
&out_handle, &out_tok);
goto out;
out_err:
out:
if (ctx_token.value != NULL)
free(ctx_token.value);
printerr(1, "finished handling null request\n");
return;
}
|