#include "includes.h"
#include "auth/ntlmssp/ntlmssp.h"
-#include "../libcli/auth/libcli_auth.h"
-#include "../lib/crypto/crypto.h"
#include "auth/gensec/gensec.h"
-
-#define CLI_SIGN "session key to client-to-server signing key magic constant"
-#define CLI_SEAL "session key to client-to-server sealing key magic constant"
-#define SRV_SIGN "session key to server-to-client signing key magic constant"
-#define SRV_SEAL "session key to server-to-client sealing key magic constant"
-
-/**
- * Some notes on the NTLM2 code:
- *
- * NTLM2 is a AEAD system. This means that the data encrypted is not
- * all the data that is signed. In DCE-RPC case, the headers of the
- * DCE-RPC packets are also signed. This prevents some of the
- * fun-and-games one might have by changing them.
- *
- */
-
-static void dump_arc4_state(const char *description,
- struct arcfour_state *state)
-{
- dump_data_pw(description, state->sbox, sizeof(state->sbox));
-}
-
-static void calc_ntlmv2_key(uint8_t subkey[16],
- DATA_BLOB session_key,
- const char *constant)
-{
- struct MD5Context ctx3;
- MD5Init(&ctx3);
- MD5Update(&ctx3, session_key.data, session_key.length);
- MD5Update(&ctx3, (const uint8_t *)constant, strlen(constant)+1);
- MD5Final(subkey, &ctx3);
-}
-
-enum ntlmssp_direction {
- NTLMSSP_SEND,
- NTLMSSP_RECEIVE
-};
-
-struct ntlmssp_crypt_direction {
- uint32_t seq_num;
- uint8_t sign_key[16];
- struct arcfour_state seal_state;
-};
-
-union ntlmssp_crypt_state {
- /* NTLM */
- struct ntlmssp_crypt_direction ntlm;
-
- /* NTLM2 */
- struct {
- struct ntlmssp_crypt_direction sending;
- struct ntlmssp_crypt_direction receiving;
- } ntlm2;
-};
-
-static NTSTATUS ntlmssp_make_packet_signature(struct ntlmssp_state *ntlmssp_state,
- TALLOC_CTX *sig_mem_ctx,
- const uint8_t *data, size_t length,
- const uint8_t *whole_pdu, size_t pdu_length,
- enum ntlmssp_direction direction,
- DATA_BLOB *sig, bool encrypt_sig)
-{
- if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
- HMACMD5Context ctx;
- uint8_t digest[16];
- uint8_t seq_num[4];
-
- *sig = data_blob_talloc(sig_mem_ctx, NULL, NTLMSSP_SIG_SIZE);
- if (!sig->data) {
- return NT_STATUS_NO_MEMORY;
- }
-
- switch (direction) {
- case NTLMSSP_SEND:
- SIVAL(seq_num, 0, ntlmssp_state->crypt->ntlm2.sending.seq_num);
- ntlmssp_state->crypt->ntlm2.sending.seq_num++;
- hmac_md5_init_limK_to_64(ntlmssp_state->crypt->ntlm2.sending.sign_key, 16, &ctx);
- break;
- case NTLMSSP_RECEIVE:
- SIVAL(seq_num, 0, ntlmssp_state->crypt->ntlm2.receiving.seq_num);
- ntlmssp_state->crypt->ntlm2.receiving.seq_num++;
- hmac_md5_init_limK_to_64(ntlmssp_state->crypt->ntlm2.receiving.sign_key, 16, &ctx);
- break;
- }
- hmac_md5_update(seq_num, sizeof(seq_num), &ctx);
- hmac_md5_update(whole_pdu, pdu_length, &ctx);
- hmac_md5_final(digest, &ctx);
-
- if (encrypt_sig && (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH)) {
- switch (direction) {
- case NTLMSSP_SEND:
- arcfour_crypt_sbox(&ntlmssp_state->crypt->ntlm2.sending.seal_state,
- digest, 8);
- break;
- case NTLMSSP_RECEIVE:
- arcfour_crypt_sbox(&ntlmssp_state->crypt->ntlm2.receiving.seal_state,
- digest, 8);
- break;
- }
- }
-
- SIVAL(sig->data, 0, NTLMSSP_SIGN_VERSION);
- memcpy(sig->data + 4, digest, 8);
- memcpy(sig->data + 12, seq_num, 4);
-
- DEBUG(10,("NTLM2: created signature over %llu bytes of input:\n",
- (unsigned long long)pdu_length));
- dump_data(11, sig->data, sig->length);
- } else {
- bool ok;
- uint32_t crc;
-
- crc = crc32_calc_buffer(data, length);
-
- ok = msrpc_gen(sig_mem_ctx,
- sig, "dddd",
- NTLMSSP_SIGN_VERSION, 0, crc,
- ntlmssp_state->crypt->ntlm.seq_num);
- if (!ok) {
- return NT_STATUS_NO_MEMORY;
- }
- ntlmssp_state->crypt->ntlm.seq_num++;
-
- arcfour_crypt_sbox(&ntlmssp_state->crypt->ntlm.seal_state,
- sig->data+4, sig->length-4);
-
- DEBUG(10,("NTLM1: created signature over %llu bytes of input:\n",
- (unsigned long long)length));
- dump_data(11, sig->data, sig->length);
- }
- return NT_STATUS_OK;
-}
-
-NTSTATUS ntlmssp_sign_packet(struct ntlmssp_state *ntlmssp_state,
- TALLOC_CTX *sig_mem_ctx,
- const uint8_t *data, size_t length,
- const uint8_t *whole_pdu, size_t pdu_length,
- DATA_BLOB *sig)
-{
- NTSTATUS nt_status;
-
- nt_status = ntlmssp_make_packet_signature(ntlmssp_state,
- sig_mem_ctx,
- data, length,
- whole_pdu, pdu_length,
- NTLMSSP_SEND, sig, true);
-
- return nt_status;
-}
-
-/**
- * Check the signature of an incoming packet
- *
- */
-
-NTSTATUS ntlmssp_check_packet(struct ntlmssp_state *ntlmssp_state,
- TALLOC_CTX *sig_mem_ctx,
- const uint8_t *data, size_t length,
- const uint8_t *whole_pdu, size_t pdu_length,
- const DATA_BLOB *sig)
-{
- DATA_BLOB local_sig;
- NTSTATUS nt_status;
-
- if (!ntlmssp_state->session_key.length) {
- DEBUG(3, ("NO session key, cannot check packet signature\n"));
- return NT_STATUS_NO_USER_SESSION_KEY;
- }
-
- nt_status = ntlmssp_make_packet_signature(ntlmssp_state,
- sig_mem_ctx,
- data, length,
- whole_pdu, pdu_length,
- NTLMSSP_RECEIVE,
- &local_sig, true);
-
- if (!NT_STATUS_IS_OK(nt_status)) {
- DEBUG(0,("NTLMSSP packet sig creation failed with %s\n",
- nt_errstr(nt_status)));
- return nt_status;
- }
-
- if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
- if (local_sig.length != sig->length ||
- memcmp(local_sig.data, sig->data, sig->length) != 0) {
-
- DEBUG(10,("BAD SIG NTLM2: wanted signature over %llu bytes of input:\n",
- (unsigned long long)pdu_length));
- dump_data(10, local_sig.data, local_sig.length);
-
- DEBUG(10,("BAD SIG: got signature over %llu bytes of input:\n",
- (unsigned long long)pdu_length));
- dump_data(10, sig->data, sig->length);
-
- data_blob_free(&local_sig);
- return NT_STATUS_ACCESS_DENIED;
- }
- } else {
- if (local_sig.length != sig->length ||
- memcmp(local_sig.data + 8, sig->data + 8, sig->length - 8) != 0) {
- DEBUG(10,("BAD SIG NTLM1: wanted signature of %llu bytes of input:\n",
- (unsigned long long)length));
- dump_data(5, local_sig.data, local_sig.length);
-
- DEBUG(10,("BAD SIG: got signature of %llu bytes of input:\n",
- (unsigned long long)length));
- dump_data(10, sig->data, sig->length);
-
- data_blob_free(&local_sig);
- return NT_STATUS_ACCESS_DENIED;
- }
- }
- dump_data_pw("checked ntlmssp signature\n", sig->data, sig->length);
-
- data_blob_free(&local_sig);
- return NT_STATUS_OK;
-}
-
-
-/**
- * Seal data with the NTLMSSP algorithm
- *
- */
-
-NTSTATUS ntlmssp_seal_packet(struct ntlmssp_state *ntlmssp_state,
- TALLOC_CTX *sig_mem_ctx,
- uint8_t *data, size_t length,
- const uint8_t *whole_pdu, size_t pdu_length,
- DATA_BLOB *sig)
-{
- if (!ntlmssp_state->session_key.length) {
- DEBUG(3, ("NO session key, cannot seal packet\n"));
- return NT_STATUS_NO_USER_SESSION_KEY;
- }
-
- DEBUG(10,("ntlmssp_seal_data: seal\n"));
- dump_data_pw("ntlmssp clear data\n", data, length);
- if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
- NTSTATUS nt_status;
- /*
- * The order of these two operations matters - we
- * must first seal the packet, then seal the
- * sequence number - this is because the
- * send_seal_hash is not constant, but is is rather
- * updated with each iteration
- */
- nt_status = ntlmssp_make_packet_signature(ntlmssp_state,
- sig_mem_ctx,
- data, length,
- whole_pdu, pdu_length,
- NTLMSSP_SEND,
- sig, false);
- if (!NT_STATUS_IS_OK(nt_status)) {
- return nt_status;
- }
-
- arcfour_crypt_sbox(&ntlmssp_state->crypt->ntlm2.sending.seal_state,
- data, length);
- if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
- arcfour_crypt_sbox(&ntlmssp_state->crypt->ntlm2.sending.seal_state,
- sig->data+4, 8);
- }
- } else {
- bool ok;
- uint32_t crc;
-
- crc = crc32_calc_buffer(data, length);
-
- ok = msrpc_gen(sig_mem_ctx,
- sig, "dddd",
- NTLMSSP_SIGN_VERSION, 0, crc,
- ntlmssp_state->crypt->ntlm.seq_num);
- if (!ok) {
- return NT_STATUS_NO_MEMORY;
- }
-
- /*
- * The order of these two operations matters - we
- * must first seal the packet, then seal the
- * sequence number - this is because the ntlmv1_arc4_state
- * is not constant, but is is rather updated with
- * each iteration
- */
-
- arcfour_crypt_sbox(&ntlmssp_state->crypt->ntlm.seal_state,
- data, length);
-
- arcfour_crypt_sbox(&ntlmssp_state->crypt->ntlm.seal_state,
- sig->data+4, sig->length-4);
-
- ntlmssp_state->crypt->ntlm.seq_num++;
- }
- dump_data_pw("ntlmssp signature\n", sig->data, sig->length);
- dump_data_pw("ntlmssp sealed data\n", data, length);
-
- return NT_STATUS_OK;
-}
-
-/**
- * Unseal data with the NTLMSSP algorithm
- *
- */
-
-NTSTATUS ntlmssp_unseal_packet(struct ntlmssp_state *ntlmssp_state,
- TALLOC_CTX *sig_mem_ctx,
- uint8_t *data, size_t length,
- const uint8_t *whole_pdu, size_t pdu_length,
- const DATA_BLOB *sig)
-{
- NTSTATUS status;
-
- if (!ntlmssp_state->session_key.length) {
- DEBUG(3, ("NO session key, cannot unseal packet\n"));
- return NT_STATUS_NO_USER_SESSION_KEY;
- }
-
- dump_data_pw("ntlmssp sealed data\n", data, length);
- if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
- arcfour_crypt_sbox(&ntlmssp_state->crypt->ntlm2.receiving.seal_state,
- data, length);
- } else {
- arcfour_crypt_sbox(&ntlmssp_state->crypt->ntlm.seal_state,
- data, length);
- }
- dump_data_pw("ntlmssp clear data\n", data, length);
- status = ntlmssp_check_packet(ntlmssp_state,
- sig_mem_ctx,
- data, length,
- whole_pdu, pdu_length,
- sig);
-
- if (!NT_STATUS_IS_OK(status)) {
- DEBUG(1,("NTLMSSP packet check for unseal failed due to invalid signature on %llu bytes of input:\n",
- (unsigned long long)length));
- }
- return status;
-}
-
-/**
- Initialise the state for NTLMSSP signing.
-*/
-NTSTATUS ntlmssp_sign_init(struct ntlmssp_state *ntlmssp_state)
-{
- DEBUG(3, ("NTLMSSP Sign/Seal - Initialising with flags:\n"));
- debug_ntlmssp_flags(ntlmssp_state->neg_flags);
-
- if (ntlmssp_state->session_key.length < 8) {
- DEBUG(3, ("NO session key, cannot intialise signing\n"));
- return NT_STATUS_NO_USER_SESSION_KEY;
- }
-
- ntlmssp_state->crypt = talloc_zero(ntlmssp_state,
- union ntlmssp_crypt_state);
- if (ntlmssp_state->crypt == NULL) {
- return NT_STATUS_NO_MEMORY;
- }
-
- if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
- DATA_BLOB weak_session_key = ntlmssp_state->session_key;
- const char *send_sign_const;
- const char *send_seal_const;
- const char *recv_sign_const;
- const char *recv_seal_const;
- uint8_t send_seal_key[16];
- DATA_BLOB send_seal_blob = data_blob_const(send_seal_key,
- sizeof(send_seal_key));
- uint8_t recv_seal_key[16];
- DATA_BLOB recv_seal_blob = data_blob_const(recv_seal_key,
- sizeof(recv_seal_key));
-
- switch (ntlmssp_state->role) {
- case NTLMSSP_CLIENT:
- send_sign_const = CLI_SIGN;
- send_seal_const = CLI_SEAL;
- recv_sign_const = SRV_SIGN;
- recv_seal_const = SRV_SEAL;
- break;
- case NTLMSSP_SERVER:
- send_sign_const = SRV_SIGN;
- send_seal_const = SRV_SEAL;
- recv_sign_const = CLI_SIGN;
- recv_seal_const = CLI_SEAL;
- break;
- default:
- return NT_STATUS_INTERNAL_ERROR;
- }
-
- /*
- * Weaken NTLMSSP keys to cope with down-level
- * clients, servers and export restrictions.
- *
- * We probably should have some parameters to
- * control this, once we get NTLM2 working.
- *
- * Key weakening was not performed on the master key
- * for NTLM2, but must be done on the encryption subkeys only.
- */
-
- if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_128) {
- /* nothing to do */
- } else if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_56) {
- weak_session_key.length = 7;
- } else { /* forty bits */
- weak_session_key.length = 5;
- }
-
- dump_data_pw("NTLMSSP weakend master key:\n",
- weak_session_key.data,
- weak_session_key.length);
-
- /* SEND: sign key */
- calc_ntlmv2_key(ntlmssp_state->crypt->ntlm2.sending.sign_key,
- ntlmssp_state->session_key, send_sign_const);
- dump_data_pw("NTLMSSP send sign key:\n",
- ntlmssp_state->crypt->ntlm2.sending.sign_key, 16);
-
- /* SEND: seal ARCFOUR pad */
- calc_ntlmv2_key(send_seal_key,
- weak_session_key, send_seal_const);
- dump_data_pw("NTLMSSP send seal key:\n", send_seal_key, 16);
-
- arcfour_init(&ntlmssp_state->crypt->ntlm2.sending.seal_state,
- &send_seal_blob);
-
- dump_arc4_state("NTLMSSP send seal arc4 state:\n",
- &ntlmssp_state->crypt->ntlm2.sending.seal_state);
-
- /* SEND: seq num */
- ntlmssp_state->crypt->ntlm2.sending.seq_num = 0;
-
- /* RECV: sign key */
- calc_ntlmv2_key(ntlmssp_state->crypt->ntlm2.receiving.sign_key,
- ntlmssp_state->session_key, recv_sign_const);
- dump_data_pw("NTLMSSP recv sign key:\n",
- ntlmssp_state->crypt->ntlm2.receiving.sign_key, 16);
-
- /* RECV: seal ARCFOUR pad */
- calc_ntlmv2_key(recv_seal_key,
- weak_session_key, recv_seal_const);
- dump_data_pw("NTLMSSP recv seal key:\n", recv_seal_key, 16);
-
- arcfour_init(&ntlmssp_state->crypt->ntlm2.receiving.seal_state,
- &recv_seal_blob);
-
- dump_arc4_state("NTLMSSP recv seal arc4 state:\n",
- &ntlmssp_state->crypt->ntlm2.receiving.seal_state);
-
- /* RECV: seq num */
- ntlmssp_state->crypt->ntlm2.receiving.seq_num = 0;
- } else {
- uint8_t weak_session_key[8];
- DATA_BLOB seal_session_key = ntlmssp_state->session_key;
- bool do_weak = false;
-
- DEBUG(5, ("NTLMSSP Sign/Seal - using NTLM1\n"));
-
- /*
- * Key weakening not performed on the master key for NTLM2
- * and does not occour for NTLM1. Therefore we only need
- * to do this for the LM_KEY.
- */
- if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_LM_KEY) {
- do_weak = true;
- }
-
- /*
- * Nothing to weaken.
- * We certainly don't want to 'extend' the length...
- */
- if (seal_session_key.length < 16) {
- /* TODO: is this really correct? */
- do_weak = false;
- }
-
- if (do_weak) {
- memcpy(weak_session_key, seal_session_key.data, 8);
- seal_session_key = data_blob_const(weak_session_key, 8);
-
- /*
- * LM key doesn't support 128 bit crypto, so this is
- * the best we can do. If you negotiate 128 bit, but
- * not 56, you end up with 40 bit...
- */
- if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_56) {
- weak_session_key[7] = 0xa0;
- } else { /* forty bits */
- weak_session_key[5] = 0xe5;
- weak_session_key[6] = 0x38;
- weak_session_key[7] = 0xb0;
- }
- }
-
- arcfour_init(&ntlmssp_state->crypt->ntlm.seal_state,
- &seal_session_key);
-
- dump_arc4_state("NTLMv1 arc4 state:\n",
- &ntlmssp_state->crypt->ntlm.seal_state);
-
- ntlmssp_state->crypt->ntlm.seq_num = 0;
- }
-
- return NT_STATUS_OK;
-}
+#include "../libcli/auth/ntlmssp_private.h"
NTSTATUS gensec_ntlmssp_sign_packet(struct gensec_security *gensec_security,
TALLOC_CTX *sig_mem_ctx,
NTSTATUS nt_status;
nt_status = ntlmssp_check_packet(gensec_ntlmssp->ntlmssp_state,
- sig_mem_ctx,
data, length,
whole_pdu, pdu_length,
sig);
NTSTATUS nt_status;
nt_status = ntlmssp_unseal_packet(gensec_ntlmssp->ntlmssp_state,
- sig_mem_ctx,
data, length,
whole_pdu, pdu_length,
sig);
git.samba.org / samba.git / commitdiff