/* draft-ietf-krb-wg-gssapi-cfx-02 plus discussed changes */
#include <assert.h>
-#include "k5-platform.h"
+#include "k5-platform.h" /* for 64-bit support */
+#include "k5-int.h" /* for zap() */
#include "gssapiP_krb5.h"
#include <stdarg.h>
return 1;
}
-static void
-copy_with_right_rotate (void *dest, void *src, size_t bufsiz, size_t rc)
-{
- if (bufsiz == 0)
- return;
- rc %= bufsiz;
- if (rc == 0) {
- memcpy(dest, src, bufsiz);
- return;
- }
- memcpy(dest, (char*)src + bufsiz - rc, rc);
- memcpy((char*)dest + rc, src, bufsiz - rc);
-}
-
krb5_error_code
gss_krb5int_make_seal_token_v3 (krb5_context context,
krb5_gss_ctx_id_rec *ctx,
size_t bufsize = 16, cksumsize;
unsigned char *outbuf = 0, *tmpbuf = 0;
krb5_error_code err;
- int sign_usage, seal_usage;
+ int key_usage;
unsigned char acceptor_flag;
- gss_buffer_desc message2 = *message;
+ gss_buffer_desc *message2 = message;
size_t rrc, ec;
unsigned short tok_id;
+ static const gss_buffer_desc empty_message = { 0, 0 };
+
assert(toktype != KG_TOK_SEAL_MSG || ctx->enc != 0);
assert(ctx->big_endian == 0);
acceptor_flag = ctx->initiate ? 0 : 0x80;
- sign_usage = ctx->initiate ? KG_USAGE_INITIATOR_SIGN : KG_USAGE_ACCEPTOR_SIGN;
- seal_usage = ctx->initiate ? KG_USAGE_INITIATOR_SEAL : KG_USAGE_ACCEPTOR_SEAL;
+ key_usage = (toktype == KG_TOK_WRAP_MSG
+ ? (ctx->initiate ? KG_USAGE_INITIATOR_SIGN : KG_USAGE_ACCEPTOR_SIGN)
+ : (ctx->initiate ? KG_USAGE_INITIATOR_SEAL : KG_USAGE_ACCEPTOR_SEAL));
if (toktype == KG_TOK_WRAP_MSG && conf_req_flag) {
krb5_data plain;
cipher.ciphertext.data = outbuf + 16;
cipher.ciphertext.length = bufsize - 16;
cipher.enctype = ctx->enc->enctype;
- err = krb5_c_encrypt(context, ctx->enc, seal_usage, 0,
+ err = krb5_c_encrypt(context, ctx->enc, key_usage, 0,
&plain, &cipher);
zap(plain.data, plain.length);
free(plain.data);
tok_id = 0x0504;
+ wrap_with_checksum:
plain.length = message->length + 16;
plain.data = malloc(message->length + 16);
if (plain.data == NULL)
if (cksumsize > 0xffff)
abort();
- bufsize = 16 + message2.length + cksumsize;
+ bufsize = 16 + message2->length + cksumsize;
outbuf = malloc(bufsize);
if (outbuf == NULL) {
free(plain.data);
/* RRC */
store_16_be(0, outbuf+6);
} else {
- /* MIC and DEL store 0xFF. */
+ /* MIC and DEL store 0xFF in EC and RRC. */
store_16_be(0xffff, outbuf+4);
- /* RRC */
store_16_be(0xffff, outbuf+6);
}
store_64_be(ctx->seq_send, outbuf+8);
- memcpy(plain.data, outbuf, 16);
- memcpy(plain.data + 16, message->data, message->length);
+ /* For DEL_CTX, the message is empty, so it doesn't matter
+ which path we use. The MIC path will probably change, for
+ security reasons. */
+ if (toktype != KG_TOK_MIC_MSG) {
+ memcpy(plain.data, outbuf, 16);
+ memcpy(plain.data + 16, message->value, message->length);
+ } else {
+ memcpy(plain.data, message->value, message->length);
+ memcpy(plain.data+message->length, outbuf, 16);
+ }
sum.length = cksumsize;
sum.contents = outbuf + 16;
+ err = krb5_c_make_checksum(context, ctx->cksumtype, ctx->enc,
+ key_usage, &plain, &sum);
+
ctx->seq_send++;
rrc = rand() & 0xffff;
if (toktype == KG_TOK_WRAP_MSG)
store_16_be(cksumsize, outbuf+4);
} else if (toktype == KG_TOK_MIC_MSG) {
- tok_id = ...;
- message2 ...;
- mic_del_common:
- ;
+ tok_id = 0x0404;
+ message2 = &empty_message;
+ goto wrap_with_checksum;
} else if (toktype == KG_TOK_DEL_CTX) {
tok_id = 0x0405;
- message2.length = 0;
- message2.data = NULL;
- goto mic_del_common;
+ message = message2 = &empty_message;
+ goto wrap_with_checksum;
} else
abort();
- } else {
- /* Just adding a checksum. */
- bufsize += cksumsize = krb5_checksum_size (context, ctx->cksumtype);
- assert(bufsize > 16);
- if (toktype == KG_TOK_WRAP_MSG) {
- bufsize += message->length;
- assert(bufsize > message->length);
- }
- ec = 0;
- }
- outbuf = malloc(bufsize);
- if (outbuf == NULL)
- return ENOMEM;
-
- switch (toktype) {
- case KG_TOK_WRAP_MSG:
- /* TOK_ID */
- store_16_be(0x0504, outbuf);
- /* flags */
- /* no acceptor subkey stuff yet */
- outbuf[2] = acceptor_flag | (conf_req_flag ? 0x80 : 0);
- /* filler */
- outbuf[3] = 0xff;
- /* EC */
- store_16_be(0, outbuf+4);
- /* RRC */
- store_16_be(0, outbuf+6);
- store_64_be(ctx->seq_send, outbuf+8);
- ctx->seq_send++; /* XXX What if an error occurs? */
- if (conf_req_flag) {
- krb5_data plain;
- krb5_enc_data cipher;
-
- memcpy(outbuf+16, message->value, message->length);
- memcpy(outbuf+16+message->length, outbuf, 16);
- plain.data = outbuf+16;
- plain.length = message->length + 16;
- cipher.enctype = ctx->enc->enctype;
- cipher.ciphertext.data = outbuf+16;
- cipher.ciphertext.length = bufsize - 16;
- err = krb5_c_encrypt (context, ctx->enc, seal_usage, 0,
- &plain, &cipher);
- if (err)
- goto error;
- } else {
- krb5_data plain;
- krb5_checksum sum;
- tmpbuf = malloc(16 + message->length);
- if (tmpbuf == NULL) {
- err = ENOMEM;
- goto error;
- }
- memcpy(tmpbuf, message->value, message->length);
- memcpy(tmpbuf + message->length, outbuf, 16);
- memcpy(outbuf+16, message->value, message->length);
- plain.data = tmpbuf;
- plain.length = 16 + message->length;
- sum.length = cksumsize;
- sum.contents = outbuf + plain.length;
- err = krb5_c_make_checksum(context, ctx->cksumtype, ctx->enc,
- /* Despite only making a
- checksum, the spec says the
- seal usage value is
- used. */
- seal_usage,
- &plain, &sum);
- if (err)
- goto error;
- }
-
- rrc = rand() & 0xffff;
- if (rotate_left(foo+16, foo-16, (foo-16) - (rrc % (foo - 16))))
- store_16_be(0, outbuf+6);
- /* If the rotate fails, don't worry about it. */
- break;
+#if 0
case KG_TOK_MIC_MSG:
store_16_be(0x0404, outbuf);
mic_del_common:
store_64_be(ctx->seq, outbuf + 8);
sum.length = cksumsize;
sum.contents = outbuf + 16;
- plain.length = 16 + message2.length;
+ plain.length = 16 + message2->length;
tmpbuf = malloc(plain.length);
if (tmpbuf == NULL) {
err = ENOMEM;
}
plain.data = tmpbuf;
memcpy(plain.data, outbuf, 16);
- memcpy(plain.data + 16, message2.value, message2.length);
+ memcpy(plain.data + 16, message2->value, message2->length);
err = krb5_c_make_checksum(context, ctx->cksumtype, ctx->enc,
sign_usage, &plain, &sum);
if (err)
goto error;
}
break;
- case KG_TOK_DEL_CTX:
- default:
- abort();
- }
+#endif
free(tmpbuf);
token->value = outbuf;
error:
free(tmpbuf);
free(outbuf);
+ token->value = NULL;
+ token->length = 0;
return err;
}
projects / thirdparty / krb5.git / commitdiff
