mirror of
https://github.com/samba-team/samba.git
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auth/gensec: move libcli/auth/schannel_sign.c into schannel.c
Signed-off-by: Stefan Metzmacher <metze@samba.org> Reviewed-by: Andrew Bartlett <abartlet@samba.org>
This commit is contained in:
Stefan Metzmacher
parent
54b5b3067f
commit
616cd00995
@ -31,6 +31,386 @@
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#include "librpc/gen_ndr/dcerpc.h"
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#include "param/param.h"
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#include "auth/gensec/gensec_toplevel_proto.h"
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#include "lib/crypto/crypto.h"
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struct schannel_state {
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uint64_t seq_num;
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bool initiator;
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struct netlogon_creds_CredentialState *creds;
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};
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#define SETUP_SEQNUM(state, buf, initiator) do { \
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uint8_t *_buf = buf; \
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uint32_t _seq_num_low = (state)->seq_num & UINT32_MAX; \
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uint32_t _seq_num_high = (state)->seq_num >> 32; \
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if (initiator) { \
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_seq_num_high |= 0x80000000; \
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} \
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RSIVAL(_buf, 0, _seq_num_low); \
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RSIVAL(_buf, 4, _seq_num_high); \
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} while(0)
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static struct schannel_state *netsec_create_state(TALLOC_CTX *mem_ctx,
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struct netlogon_creds_CredentialState *creds,
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bool initiator)
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{
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struct schannel_state *state;
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state = talloc(mem_ctx, struct schannel_state);
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if (state == NULL) {
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return NULL;
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}
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state->initiator = initiator;
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state->seq_num = 0;
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state->creds = netlogon_creds_copy(state, creds);
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if (state->creds == NULL) {
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talloc_free(state);
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return NULL;
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}
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return state;
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}
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static void netsec_offset_and_sizes(struct schannel_state *state,
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bool do_seal,
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uint32_t *_min_sig_size,
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uint32_t *_used_sig_size,
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uint32_t *_checksum_length,
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uint32_t *_confounder_ofs)
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{
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uint32_t min_sig_size;
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uint32_t used_sig_size;
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uint32_t checksum_length;
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uint32_t confounder_ofs;
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if (state->creds->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) {
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min_sig_size = 48;
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used_sig_size = 56;
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/*
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* Note: windows has a bug here and uses the old values...
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*
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* checksum_length = 32;
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* confounder_ofs = 48;
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*/
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checksum_length = 8;
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confounder_ofs = 24;
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} else {
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min_sig_size = 24;
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used_sig_size = 32;
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checksum_length = 8;
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confounder_ofs = 24;
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}
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if (do_seal) {
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min_sig_size += 8;
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}
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if (_min_sig_size) {
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*_min_sig_size = min_sig_size;
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}
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if (_used_sig_size) {
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*_used_sig_size = used_sig_size;
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}
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if (_checksum_length) {
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*_checksum_length = checksum_length;
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}
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if (_confounder_ofs) {
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*_confounder_ofs = confounder_ofs;
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}
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}
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/*******************************************************************
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Encode or Decode the sequence number (which is symmetric)
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********************************************************************/
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static void netsec_do_seq_num(struct schannel_state *state,
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const uint8_t *checksum,
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uint32_t checksum_length,
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uint8_t seq_num[8])
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{
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if (state->creds->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) {
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AES_KEY key;
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uint8_t iv[AES_BLOCK_SIZE];
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AES_set_encrypt_key(state->creds->session_key, 128, &key);
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ZERO_STRUCT(iv);
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memcpy(iv+0, checksum, 8);
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memcpy(iv+8, checksum, 8);
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aes_cfb8_encrypt(seq_num, seq_num, 8, &key, iv, AES_ENCRYPT);
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} else {
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static const uint8_t zeros[4];
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uint8_t sequence_key[16];
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uint8_t digest1[16];
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hmac_md5(state->creds->session_key, zeros, sizeof(zeros), digest1);
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hmac_md5(digest1, checksum, checksum_length, sequence_key);
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arcfour_crypt(seq_num, sequence_key, 8);
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}
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state->seq_num++;
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}
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static void netsec_do_seal(struct schannel_state *state,
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const uint8_t seq_num[8],
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uint8_t confounder[8],
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uint8_t *data, uint32_t length,
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bool forward)
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{
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if (state->creds->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) {
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AES_KEY key;
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uint8_t iv[AES_BLOCK_SIZE];
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uint8_t sess_kf0[16];
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int i;
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for (i = 0; i < 16; i++) {
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sess_kf0[i] = state->creds->session_key[i] ^ 0xf0;
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}
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AES_set_encrypt_key(sess_kf0, 128, &key);
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ZERO_STRUCT(iv);
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memcpy(iv+0, seq_num, 8);
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memcpy(iv+8, seq_num, 8);
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if (forward) {
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aes_cfb8_encrypt(confounder, confounder, 8, &key, iv, AES_ENCRYPT);
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aes_cfb8_encrypt(data, data, length, &key, iv, AES_ENCRYPT);
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} else {
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aes_cfb8_encrypt(confounder, confounder, 8, &key, iv, AES_DECRYPT);
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aes_cfb8_encrypt(data, data, length, &key, iv, AES_DECRYPT);
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}
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} else {
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uint8_t sealing_key[16];
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static const uint8_t zeros[4];
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uint8_t digest2[16];
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uint8_t sess_kf0[16];
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int i;
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for (i = 0; i < 16; i++) {
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sess_kf0[i] = state->creds->session_key[i] ^ 0xf0;
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}
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hmac_md5(sess_kf0, zeros, 4, digest2);
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hmac_md5(digest2, seq_num, 8, sealing_key);
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arcfour_crypt(confounder, sealing_key, 8);
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arcfour_crypt(data, sealing_key, length);
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}
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}
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/*******************************************************************
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Create a digest over the entire packet (including the data), and
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MD5 it with the session key.
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********************************************************************/
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static void netsec_do_sign(struct schannel_state *state,
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const uint8_t *confounder,
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const uint8_t *data, size_t length,
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uint8_t header[8],
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uint8_t *checksum)
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{
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if (state->creds->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) {
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struct HMACSHA256Context ctx;
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hmac_sha256_init(state->creds->session_key,
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sizeof(state->creds->session_key),
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&ctx);
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if (confounder) {
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SSVAL(header, 0, NL_SIGN_HMAC_SHA256);
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SSVAL(header, 2, NL_SEAL_AES128);
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SSVAL(header, 4, 0xFFFF);
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SSVAL(header, 6, 0x0000);
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hmac_sha256_update(header, 8, &ctx);
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hmac_sha256_update(confounder, 8, &ctx);
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} else {
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SSVAL(header, 0, NL_SIGN_HMAC_SHA256);
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SSVAL(header, 2, NL_SEAL_NONE);
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SSVAL(header, 4, 0xFFFF);
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SSVAL(header, 6, 0x0000);
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hmac_sha256_update(header, 8, &ctx);
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}
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hmac_sha256_update(data, length, &ctx);
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hmac_sha256_final(checksum, &ctx);
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} else {
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uint8_t packet_digest[16];
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static const uint8_t zeros[4];
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MD5_CTX ctx;
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MD5Init(&ctx);
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MD5Update(&ctx, zeros, 4);
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if (confounder) {
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SSVAL(header, 0, NL_SIGN_HMAC_MD5);
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SSVAL(header, 2, NL_SEAL_RC4);
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SSVAL(header, 4, 0xFFFF);
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SSVAL(header, 6, 0x0000);
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MD5Update(&ctx, header, 8);
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MD5Update(&ctx, confounder, 8);
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} else {
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SSVAL(header, 0, NL_SIGN_HMAC_MD5);
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SSVAL(header, 2, NL_SEAL_NONE);
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SSVAL(header, 4, 0xFFFF);
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SSVAL(header, 6, 0x0000);
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MD5Update(&ctx, header, 8);
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}
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MD5Update(&ctx, data, length);
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MD5Final(packet_digest, &ctx);
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hmac_md5(state->creds->session_key,
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packet_digest, sizeof(packet_digest),
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checksum);
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}
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}
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static NTSTATUS netsec_incoming_packet(struct schannel_state *state,
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bool do_unseal,
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uint8_t *data, size_t length,
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const DATA_BLOB *sig)
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{
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uint32_t min_sig_size = 0;
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uint8_t header[8];
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uint8_t checksum[32];
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uint32_t checksum_length = sizeof(checksum_length);
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uint8_t _confounder[8];
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uint8_t *confounder = NULL;
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uint32_t confounder_ofs = 0;
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uint8_t seq_num[8];
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int ret;
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netsec_offset_and_sizes(state,
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do_unseal,
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&min_sig_size,
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NULL,
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&checksum_length,
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&confounder_ofs);
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if (sig->length < min_sig_size) {
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return NT_STATUS_ACCESS_DENIED;
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}
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if (do_unseal) {
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confounder = _confounder;
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memcpy(confounder, sig->data+confounder_ofs, 8);
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} else {
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confounder = NULL;
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}
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SETUP_SEQNUM(state, seq_num, !state->initiator);
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if (do_unseal) {
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netsec_do_seal(state, seq_num,
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confounder,
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data, length,
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false);
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}
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netsec_do_sign(state, confounder,
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data, length,
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header, checksum);
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ret = memcmp(checksum, sig->data+16, checksum_length);
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if (ret != 0) {
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dump_data_pw("calc digest:", checksum, checksum_length);
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dump_data_pw("wire digest:", sig->data+16, checksum_length);
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return NT_STATUS_ACCESS_DENIED;
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}
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netsec_do_seq_num(state, checksum, checksum_length, seq_num);
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ret = memcmp(seq_num, sig->data+8, 8);
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if (ret != 0) {
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dump_data_pw("calc seq num:", seq_num, 8);
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dump_data_pw("wire seq num:", sig->data+8, 8);
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return NT_STATUS_ACCESS_DENIED;
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}
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return NT_STATUS_OK;
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}
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static uint32_t netsec_outgoing_sig_size(struct schannel_state *state)
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{
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uint32_t sig_size = 0;
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netsec_offset_and_sizes(state,
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true,
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NULL,
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&sig_size,
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NULL,
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NULL);
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return sig_size;
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}
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static NTSTATUS netsec_outgoing_packet(struct schannel_state *state,
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TALLOC_CTX *mem_ctx,
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bool do_seal,
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uint8_t *data, size_t length,
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DATA_BLOB *sig)
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{
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uint32_t min_sig_size = 0;
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uint32_t used_sig_size = 0;
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uint8_t header[8];
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uint8_t checksum[32];
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uint32_t checksum_length = sizeof(checksum_length);
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uint8_t _confounder[8];
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uint8_t *confounder = NULL;
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uint32_t confounder_ofs = 0;
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uint8_t seq_num[8];
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netsec_offset_and_sizes(state,
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do_seal,
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&min_sig_size,
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&used_sig_size,
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&checksum_length,
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&confounder_ofs);
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SETUP_SEQNUM(state, seq_num, state->initiator);
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if (do_seal) {
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confounder = _confounder;
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generate_random_buffer(confounder, 8);
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} else {
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confounder = NULL;
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}
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netsec_do_sign(state, confounder,
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data, length,
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header, checksum);
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if (do_seal) {
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netsec_do_seal(state, seq_num,
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confounder,
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data, length,
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true);
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}
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netsec_do_seq_num(state, checksum, checksum_length, seq_num);
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(*sig) = data_blob_talloc_zero(mem_ctx, used_sig_size);
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memcpy(sig->data, header, 8);
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memcpy(sig->data+8, seq_num, 8);
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memcpy(sig->data+16, checksum, checksum_length);
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if (confounder) {
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memcpy(sig->data+confounder_ofs, confounder, 8);
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}
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dump_data_pw("signature:", sig->data+ 0, 8);
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dump_data_pw("seq_num :", sig->data+ 8, 8);
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dump_data_pw("digest :", sig->data+16, checksum_length);
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dump_data_pw("confound :", sig->data+confounder_ofs, 8);
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return NT_STATUS_OK;
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}
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_PUBLIC_ NTSTATUS gensec_schannel_init(void);
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@ -28,18 +28,4 @@ struct schannel_state;
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struct db_context *open_schannel_session_store(TALLOC_CTX *mem_ctx,
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struct loadparm_context *lp_ctx);
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struct schannel_state *netsec_create_state(TALLOC_CTX *mem_ctx,
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struct netlogon_creds_CredentialState *creds,
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bool initiator);
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NTSTATUS netsec_incoming_packet(struct schannel_state *state,
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bool do_unseal,
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uint8_t *data, size_t length,
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const DATA_BLOB *sig);
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uint32_t netsec_outgoing_sig_size(struct schannel_state *state);
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NTSTATUS netsec_outgoing_packet(struct schannel_state *state,
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TALLOC_CTX *mem_ctx,
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bool do_seal,
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uint8_t *data, size_t length,
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DATA_BLOB *sig);
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#endif
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@ -1,404 +0,0 @@
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/*
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Unix SMB/CIFS implementation.
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schannel library code
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Copyright (C) Andrew Tridgell 2004
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Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include "includes.h"
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#include "../libcli/auth/schannel.h"
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#include "../lib/crypto/crypto.h"
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struct schannel_state {
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uint64_t seq_num;
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bool initiator;
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struct netlogon_creds_CredentialState *creds;
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};
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#define SETUP_SEQNUM(state, buf, initiator) do { \
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uint8_t *_buf = buf; \
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uint32_t _seq_num_low = (state)->seq_num & UINT32_MAX; \
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uint32_t _seq_num_high = (state)->seq_num >> 32; \
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if (initiator) { \
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_seq_num_high |= 0x80000000; \
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} \
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RSIVAL(_buf, 0, _seq_num_low); \
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RSIVAL(_buf, 4, _seq_num_high); \
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} while(0)
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struct schannel_state *netsec_create_state(TALLOC_CTX *mem_ctx,
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struct netlogon_creds_CredentialState *creds,
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bool initiator)
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{
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struct schannel_state *state;
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state = talloc(mem_ctx, struct schannel_state);
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if (state == NULL) {
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return NULL;
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}
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state->initiator = initiator;
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state->seq_num = 0;
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state->creds = netlogon_creds_copy(state, creds);
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if (state->creds == NULL) {
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talloc_free(state);
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return NULL;
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}
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return state;
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}
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static void netsec_offset_and_sizes(struct schannel_state *state,
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bool do_seal,
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uint32_t *_min_sig_size,
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uint32_t *_used_sig_size,
|
||||
uint32_t *_checksum_length,
|
||||
uint32_t *_confounder_ofs)
|
||||
{
|
||||
uint32_t min_sig_size;
|
||||
uint32_t used_sig_size;
|
||||
uint32_t checksum_length;
|
||||
uint32_t confounder_ofs;
|
||||
|
||||
if (state->creds->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) {
|
||||
min_sig_size = 48;
|
||||
used_sig_size = 56;
|
||||
/*
|
||||
* Note: windows has a bug here and uses the old values...
|
||||
*
|
||||
* checksum_length = 32;
|
||||
* confounder_ofs = 48;
|
||||
*/
|
||||
checksum_length = 8;
|
||||
confounder_ofs = 24;
|
||||
} else {
|
||||
min_sig_size = 24;
|
||||
used_sig_size = 32;
|
||||
checksum_length = 8;
|
||||
confounder_ofs = 24;
|
||||
}
|
||||
|
||||
if (do_seal) {
|
||||
min_sig_size += 8;
|
||||
}
|
||||
|
||||
if (_min_sig_size) {
|
||||
*_min_sig_size = min_sig_size;
|
||||
}
|
||||
|
||||
if (_used_sig_size) {
|
||||
*_used_sig_size = used_sig_size;
|
||||
}
|
||||
|
||||
if (_checksum_length) {
|
||||
*_checksum_length = checksum_length;
|
||||
}
|
||||
|
||||
if (_confounder_ofs) {
|
||||
*_confounder_ofs = confounder_ofs;
|
||||
}
|
||||
}
|
||||
|
||||
/*******************************************************************
|
||||
Encode or Decode the sequence number (which is symmetric)
|
||||
********************************************************************/
|
||||
static void netsec_do_seq_num(struct schannel_state *state,
|
||||
const uint8_t *checksum,
|
||||
uint32_t checksum_length,
|
||||
uint8_t seq_num[8])
|
||||
{
|
||||
if (state->creds->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) {
|
||||
AES_KEY key;
|
||||
uint8_t iv[AES_BLOCK_SIZE];
|
||||
|
||||
AES_set_encrypt_key(state->creds->session_key, 128, &key);
|
||||
ZERO_STRUCT(iv);
|
||||
memcpy(iv+0, checksum, 8);
|
||||
memcpy(iv+8, checksum, 8);
|
||||
|
||||
aes_cfb8_encrypt(seq_num, seq_num, 8, &key, iv, AES_ENCRYPT);
|
||||
} else {
|
||||
static const uint8_t zeros[4];
|
||||
uint8_t sequence_key[16];
|
||||
uint8_t digest1[16];
|
||||
|
||||
hmac_md5(state->creds->session_key, zeros, sizeof(zeros), digest1);
|
||||
hmac_md5(digest1, checksum, checksum_length, sequence_key);
|
||||
arcfour_crypt(seq_num, sequence_key, 8);
|
||||
}
|
||||
|
||||
state->seq_num++;
|
||||
}
|
||||
|
||||
static void netsec_do_seal(struct schannel_state *state,
|
||||
const uint8_t seq_num[8],
|
||||
uint8_t confounder[8],
|
||||
uint8_t *data, uint32_t length,
|
||||
bool forward)
|
||||
{
|
||||
if (state->creds->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) {
|
||||
AES_KEY key;
|
||||
uint8_t iv[AES_BLOCK_SIZE];
|
||||
uint8_t sess_kf0[16];
|
||||
int i;
|
||||
|
||||
for (i = 0; i < 16; i++) {
|
||||
sess_kf0[i] = state->creds->session_key[i] ^ 0xf0;
|
||||
}
|
||||
|
||||
AES_set_encrypt_key(sess_kf0, 128, &key);
|
||||
ZERO_STRUCT(iv);
|
||||
memcpy(iv+0, seq_num, 8);
|
||||
memcpy(iv+8, seq_num, 8);
|
||||
|
||||
if (forward) {
|
||||
aes_cfb8_encrypt(confounder, confounder, 8, &key, iv, AES_ENCRYPT);
|
||||
aes_cfb8_encrypt(data, data, length, &key, iv, AES_ENCRYPT);
|
||||
} else {
|
||||
aes_cfb8_encrypt(confounder, confounder, 8, &key, iv, AES_DECRYPT);
|
||||
aes_cfb8_encrypt(data, data, length, &key, iv, AES_DECRYPT);
|
||||
}
|
||||
} else {
|
||||
uint8_t sealing_key[16];
|
||||
static const uint8_t zeros[4];
|
||||
uint8_t digest2[16];
|
||||
uint8_t sess_kf0[16];
|
||||
int i;
|
||||
|
||||
for (i = 0; i < 16; i++) {
|
||||
sess_kf0[i] = state->creds->session_key[i] ^ 0xf0;
|
||||
}
|
||||
|
||||
hmac_md5(sess_kf0, zeros, 4, digest2);
|
||||
hmac_md5(digest2, seq_num, 8, sealing_key);
|
||||
|
||||
arcfour_crypt(confounder, sealing_key, 8);
|
||||
arcfour_crypt(data, sealing_key, length);
|
||||
}
|
||||
}
|
||||
|
||||
/*******************************************************************
|
||||
Create a digest over the entire packet (including the data), and
|
||||
MD5 it with the session key.
|
||||
********************************************************************/
|
||||
static void netsec_do_sign(struct schannel_state *state,
|
||||
const uint8_t *confounder,
|
||||
const uint8_t *data, size_t length,
|
||||
uint8_t header[8],
|
||||
uint8_t *checksum)
|
||||
{
|
||||
if (state->creds->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) {
|
||||
struct HMACSHA256Context ctx;
|
||||
|
||||
hmac_sha256_init(state->creds->session_key,
|
||||
sizeof(state->creds->session_key),
|
||||
&ctx);
|
||||
|
||||
if (confounder) {
|
||||
SSVAL(header, 0, NL_SIGN_HMAC_SHA256);
|
||||
SSVAL(header, 2, NL_SEAL_AES128);
|
||||
SSVAL(header, 4, 0xFFFF);
|
||||
SSVAL(header, 6, 0x0000);
|
||||
|
||||
hmac_sha256_update(header, 8, &ctx);
|
||||
hmac_sha256_update(confounder, 8, &ctx);
|
||||
} else {
|
||||
SSVAL(header, 0, NL_SIGN_HMAC_SHA256);
|
||||
SSVAL(header, 2, NL_SEAL_NONE);
|
||||
SSVAL(header, 4, 0xFFFF);
|
||||
SSVAL(header, 6, 0x0000);
|
||||
|
||||
hmac_sha256_update(header, 8, &ctx);
|
||||
}
|
||||
|
||||
hmac_sha256_update(data, length, &ctx);
|
||||
|
||||
hmac_sha256_final(checksum, &ctx);
|
||||
} else {
|
||||
uint8_t packet_digest[16];
|
||||
static const uint8_t zeros[4];
|
||||
MD5_CTX ctx;
|
||||
|
||||
MD5Init(&ctx);
|
||||
MD5Update(&ctx, zeros, 4);
|
||||
if (confounder) {
|
||||
SSVAL(header, 0, NL_SIGN_HMAC_MD5);
|
||||
SSVAL(header, 2, NL_SEAL_RC4);
|
||||
SSVAL(header, 4, 0xFFFF);
|
||||
SSVAL(header, 6, 0x0000);
|
||||
|
||||
MD5Update(&ctx, header, 8);
|
||||
MD5Update(&ctx, confounder, 8);
|
||||
} else {
|
||||
SSVAL(header, 0, NL_SIGN_HMAC_MD5);
|
||||
SSVAL(header, 2, NL_SEAL_NONE);
|
||||
SSVAL(header, 4, 0xFFFF);
|
||||
SSVAL(header, 6, 0x0000);
|
||||
|
||||
MD5Update(&ctx, header, 8);
|
||||
}
|
||||
MD5Update(&ctx, data, length);
|
||||
MD5Final(packet_digest, &ctx);
|
||||
|
||||
hmac_md5(state->creds->session_key,
|
||||
packet_digest, sizeof(packet_digest),
|
||||
checksum);
|
||||
}
|
||||
}
|
||||
|
||||
NTSTATUS netsec_incoming_packet(struct schannel_state *state,
|
||||
bool do_unseal,
|
||||
uint8_t *data, size_t length,
|
||||
const DATA_BLOB *sig)
|
||||
{
|
||||
uint32_t min_sig_size = 0;
|
||||
uint8_t header[8];
|
||||
uint8_t checksum[32];
|
||||
uint32_t checksum_length = sizeof(checksum_length);
|
||||
uint8_t _confounder[8];
|
||||
uint8_t *confounder = NULL;
|
||||
uint32_t confounder_ofs = 0;
|
||||
uint8_t seq_num[8];
|
||||
int ret;
|
||||
|
||||
netsec_offset_and_sizes(state,
|
||||
do_unseal,
|
||||
&min_sig_size,
|
||||
NULL,
|
||||
&checksum_length,
|
||||
&confounder_ofs);
|
||||
|
||||
if (sig->length < min_sig_size) {
|
||||
return NT_STATUS_ACCESS_DENIED;
|
||||
}
|
||||
|
||||
if (do_unseal) {
|
||||
confounder = _confounder;
|
||||
memcpy(confounder, sig->data+confounder_ofs, 8);
|
||||
} else {
|
||||
confounder = NULL;
|
||||
}
|
||||
|
||||
SETUP_SEQNUM(state, seq_num, !state->initiator);
|
||||
|
||||
if (do_unseal) {
|
||||
netsec_do_seal(state, seq_num,
|
||||
confounder,
|
||||
data, length,
|
||||
false);
|
||||
}
|
||||
|
||||
netsec_do_sign(state, confounder,
|
||||
data, length,
|
||||
header, checksum);
|
||||
|
||||
ret = memcmp(checksum, sig->data+16, checksum_length);
|
||||
if (ret != 0) {
|
||||
dump_data_pw("calc digest:", checksum, checksum_length);
|
||||
dump_data_pw("wire digest:", sig->data+16, checksum_length);
|
||||
return NT_STATUS_ACCESS_DENIED;
|
||||
}
|
||||
|
||||
netsec_do_seq_num(state, checksum, checksum_length, seq_num);
|
||||
|
||||
ret = memcmp(seq_num, sig->data+8, 8);
|
||||
if (ret != 0) {
|
||||
dump_data_pw("calc seq num:", seq_num, 8);
|
||||
dump_data_pw("wire seq num:", sig->data+8, 8);
|
||||
return NT_STATUS_ACCESS_DENIED;
|
||||
}
|
||||
|
||||
return NT_STATUS_OK;
|
||||
}
|
||||
|
||||
uint32_t netsec_outgoing_sig_size(struct schannel_state *state)
|
||||
{
|
||||
uint32_t sig_size = 0;
|
||||
|
||||
netsec_offset_and_sizes(state,
|
||||
true,
|
||||
NULL,
|
||||
&sig_size,
|
||||
NULL,
|
||||
NULL);
|
||||
|
||||
return sig_size;
|
||||
}
|
||||
|
||||
NTSTATUS netsec_outgoing_packet(struct schannel_state *state,
|
||||
TALLOC_CTX *mem_ctx,
|
||||
bool do_seal,
|
||||
uint8_t *data, size_t length,
|
||||
DATA_BLOB *sig)
|
||||
{
|
||||
uint32_t min_sig_size = 0;
|
||||
uint32_t used_sig_size = 0;
|
||||
uint8_t header[8];
|
||||
uint8_t checksum[32];
|
||||
uint32_t checksum_length = sizeof(checksum_length);
|
||||
uint8_t _confounder[8];
|
||||
uint8_t *confounder = NULL;
|
||||
uint32_t confounder_ofs = 0;
|
||||
uint8_t seq_num[8];
|
||||
|
||||
netsec_offset_and_sizes(state,
|
||||
do_seal,
|
||||
&min_sig_size,
|
||||
&used_sig_size,
|
||||
&checksum_length,
|
||||
&confounder_ofs);
|
||||
|
||||
SETUP_SEQNUM(state, seq_num, state->initiator);
|
||||
|
||||
if (do_seal) {
|
||||
confounder = _confounder;
|
||||
generate_random_buffer(confounder, 8);
|
||||
} else {
|
||||
confounder = NULL;
|
||||
}
|
||||
|
||||
netsec_do_sign(state, confounder,
|
||||
data, length,
|
||||
header, checksum);
|
||||
|
||||
if (do_seal) {
|
||||
netsec_do_seal(state, seq_num,
|
||||
confounder,
|
||||
data, length,
|
||||
true);
|
||||
}
|
||||
|
||||
netsec_do_seq_num(state, checksum, checksum_length, seq_num);
|
||||
|
||||
(*sig) = data_blob_talloc_zero(mem_ctx, used_sig_size);
|
||||
|
||||
memcpy(sig->data, header, 8);
|
||||
memcpy(sig->data+8, seq_num, 8);
|
||||
memcpy(sig->data+16, checksum, checksum_length);
|
||||
|
||||
if (confounder) {
|
||||
memcpy(sig->data+confounder_ofs, confounder, 8);
|
||||
}
|
||||
|
||||
dump_data_pw("signature:", sig->data+ 0, 8);
|
||||
dump_data_pw("seq_num :", sig->data+ 8, 8);
|
||||
dump_data_pw("digest :", sig->data+16, checksum_length);
|
||||
dump_data_pw("confound :", sig->data+confounder_ofs, 8);
|
||||
|
||||
return NT_STATUS_OK;
|
||||
}
|
||||
@ -24,7 +24,7 @@ bld.SAMBA_SUBSYSTEM('LIBCLI_AUTH',
|
||||
|
||||
|
||||
bld.SAMBA_SUBSYSTEM('COMMON_SCHANNEL',
|
||||
source='schannel_state_tdb.c schannel_sign.c',
|
||||
source='schannel_state_tdb.c',
|
||||
deps='dbwrap util_tdb samba-hostconfig NDR_NETLOGON'
|
||||
)
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user