windows/wingss.c

   1 #ifndef NO_GSSAPI
   2
   3 #include <windows.h>
   4 #define SECURITY_WIN32
   5 #include <security.h>
   6 #include "sshgss.h"
   7 #include "misc.h"
   8
   9 #define NOTHING
  10 #define DECL_SSPI_FUNCTION(linkage, rettype, name, params)      \
  11   typedef rettype (WINAPI *t_##name) params;                    \
  12   linkage t_##name p_##name
  13 #define GET_SSPI_FUNCTION(module, name)                                 \
  14   p_##name = module ? (t_##name) GetProcAddress(module, #name) : NULL
  15
  16 DECL_SSPI_FUNCTION(static, SECURITY_STATUS,
  17                    AcquireCredentialsHandleA,
  18                    (SEC_CHAR *, SEC_CHAR *, ULONG, PLUID,
  19                     PVOID, SEC_GET_KEY_FN, PVOID, PCredHandle, PTimeStamp));
  20 DECL_SSPI_FUNCTION(static, SECURITY_STATUS,
  21                    InitializeSecurityContextA,
  22                    (PCredHandle, PCtxtHandle, SEC_CHAR *, ULONG, ULONG,
  23                    ULONG, PSecBufferDesc, ULONG, PCtxtHandle,
  24                     PSecBufferDesc, PULONG, PTimeStamp));
  25 DECL_SSPI_FUNCTION(static, SECURITY_STATUS,
  26                    FreeContextBuffer,
  27                    (PVOID));
  28 DECL_SSPI_FUNCTION(static, SECURITY_STATUS,
  29                    FreeCredentialsHandle,
  30                    (PCredHandle));
  31 DECL_SSPI_FUNCTION(static, SECURITY_STATUS,
  32                    DeleteSecurityContext,
  33                    (PCtxtHandle));
  34 DECL_SSPI_FUNCTION(static, SECURITY_STATUS,
  35                    QueryContextAttributesA,
  36                    (PCtxtHandle, ULONG, PVOID));
  37 DECL_SSPI_FUNCTION(static, SECURITY_STATUS,
  38                    MakeSignature,
  39                    (PCtxtHandle, ULONG, PSecBufferDesc, ULONG));
  40
  41 static HMODULE security_module = NULL;
  42
  43 typedef struct winSsh_gss_ctx {
  44     unsigned long maj_stat;
  45     unsigned long min_stat;
  46     CredHandle cred_handle;
  47     CtxtHandle context;
  48     PCtxtHandle context_handle;
  49     TimeStamp expiry;
  50 } winSsh_gss_ctx;
  51
  52
  53 const Ssh_gss_buf gss_mech_krb5={9,"\x2A\x86\x48\x86\xF7\x12\x01\x02\x02"};
  54
  55 int ssh_gss_init(void)
  56 {
  57     if (security_module)
  58         return 1;                      /* already initialised */
  59
  60     security_module = LoadLibrary("secur32.dll");
  61     if (security_module) {
  62         GET_SSPI_FUNCTION(security_module, AcquireCredentialsHandleA);
  63         GET_SSPI_FUNCTION(security_module, InitializeSecurityContextA);
  64         GET_SSPI_FUNCTION(security_module, FreeContextBuffer);
  65         GET_SSPI_FUNCTION(security_module, FreeCredentialsHandle);
  66         GET_SSPI_FUNCTION(security_module, DeleteSecurityContext);
  67         GET_SSPI_FUNCTION(security_module, QueryContextAttributesA);
  68         GET_SSPI_FUNCTION(security_module, MakeSignature);
  69         return 1;
  70     }
  71     return 0;
  72 }
  73
  74 Ssh_gss_stat ssh_gss_indicate_mech(Ssh_gss_buf *mech)
  75 {
  76     *mech = gss_mech_krb5;
  77     return SSH_GSS_OK;
  78 }
  79
  80
  81 Ssh_gss_stat ssh_gss_import_name(char *host, Ssh_gss_name *srv_name)
  82 {
  83     char *pStr;
  84
  85     /* Check hostname */
  86     if (host == NULL) return SSH_GSS_FAILURE;
  87
  88     /* copy it into form host/FQDN */
  89     pStr = dupcat("host/", host, NULL);
  90
  91     *srv_name = (Ssh_gss_name) pStr;
  92
  93     return SSH_GSS_OK;
  94 }
  95
  96 Ssh_gss_stat ssh_gss_acquire_cred(Ssh_gss_ctx *ctx)
  97 {
  98     winSsh_gss_ctx *winctx = snew(winSsh_gss_ctx);
  99
 100     /* prepare our "wrapper" structure */
 101     winctx->maj_stat =  winctx->min_stat = SEC_E_OK;
 102     winctx->context_handle = NULL;
 103
 104     /* Specifying no principal name here means use the credentials of
 105        the current logged-in user */
 106
 107     winctx->maj_stat = p_AcquireCredentialsHandleA(NULL,
 108                                                    "Kerberos",
 109                                                    SECPKG_CRED_OUTBOUND,
 110                                                    NULL,
 111                                                    NULL,
 112                                                    NULL,
 113                                                    NULL,
 114                                                    &winctx->cred_handle,
 115                                                    &winctx->expiry);
 116
 117     if (winctx->maj_stat != SEC_E_OK) return SSH_GSS_FAILURE;
 118
 119     *ctx = (Ssh_gss_ctx) winctx;
 120     return SSH_GSS_OK;
 121 }
 122
 123
 124 Ssh_gss_stat ssh_gss_init_sec_context(Ssh_gss_ctx *ctx,
 125                                       Ssh_gss_name srv_name,
 126                                       int to_deleg,
 127                                       Ssh_gss_buf *recv_tok,
 128                                       Ssh_gss_buf *send_tok)
 129 {
 130     winSsh_gss_ctx *winctx = (winSsh_gss_ctx *) *ctx;
 131     SecBuffer wsend_tok = {send_tok->len,SECBUFFER_TOKEN,send_tok->data};
 132     SecBuffer wrecv_tok = {recv_tok->len,SECBUFFER_TOKEN,recv_tok->data};
 133     SecBufferDesc output_desc={SECBUFFER_VERSION,1,&wsend_tok};
 134     SecBufferDesc input_desc ={SECBUFFER_VERSION,1,&wrecv_tok};
 135     unsigned long flags=ISC_REQ_MUTUAL_AUTH|ISC_REQ_REPLAY_DETECT|
 136         ISC_REQ_CONFIDENTIALITY|ISC_REQ_ALLOCATE_MEMORY;
 137     unsigned long ret_flags=0;
 138
 139     /* check if we have to delegate ... */
 140     if (to_deleg) flags |= ISC_REQ_DELEGATE;
 141     winctx->maj_stat = p_InitializeSecurityContextA(&winctx->cred_handle,
 142                                                     winctx->context_handle,
 143                                                     (char*) srv_name,
 144                                                     flags,
 145                                                     0,          /* reserved */
 146                                                     SECURITY_NATIVE_DREP,
 147                                                     &input_desc,
 148                                                     0,          /* reserved */
 149                                                     &winctx->context,
 150                                                     &output_desc,
 151                                                     &ret_flags,
 152                                                     &winctx->expiry);
 153
 154     /* prepare for the next round */
 155     winctx->context_handle = &winctx->context;
 156     send_tok->data = (char*) wsend_tok.pvBuffer;
 157     send_tok->len  =  wsend_tok.cbBuffer;
 158
 159     /* check & return our status */
 160     if (winctx->maj_stat==SEC_E_OK) return SSH_GSS_S_COMPLETE;
 161     if (winctx->maj_stat==SEC_I_CONTINUE_NEEDED) return SSH_GSS_S_CONTINUE_NEEDED;
 162
 163     return SSH_GSS_FAILURE;
 164 }
 165
 166 Ssh_gss_stat ssh_gss_free_tok(Ssh_gss_buf *send_tok)
 167 {
 168     /* check input */
 169     if (send_tok == NULL) return SSH_GSS_FAILURE;
 170
 171     /* free Windows buffer */
 172     p_FreeContextBuffer(send_tok->data);
 173     send_tok->len = 0; send_tok->data = NULL;
 174
 175     return SSH_GSS_OK;
 176 }
 177
 178 Ssh_gss_stat ssh_gss_release_cred(Ssh_gss_ctx *ctx)
 179 {
 180     winSsh_gss_ctx *winctx= (winSsh_gss_ctx *) *ctx;
 181
 182     /* check input */
 183     if (winctx == NULL) return SSH_GSS_FAILURE;
 184
 185     /* free Windows data */
 186     p_FreeCredentialsHandle(&winctx->cred_handle);
 187     p_DeleteSecurityContext(&winctx->context);
 188
 189     /* delete our "wrapper" structure */
 190     sfree(winctx);
 191     *ctx = (Ssh_gss_ctx) NULL;
 192
 193     return SSH_GSS_OK;
 194 }
 195
 196
 197 Ssh_gss_stat ssh_gss_release_name(Ssh_gss_name *srv_name)
 198 {
 199     char *pStr= (char *) *srv_name;
 200
 201     if (pStr == NULL) return SSH_GSS_FAILURE;
 202     sfree(pStr);
 203     *srv_name = (Ssh_gss_name) NULL;
 204
 205     return SSH_GSS_OK;
 206 }
 207
 208 Ssh_gss_stat ssh_gss_display_status(Ssh_gss_ctx ctx, Ssh_gss_buf *buf)
 209 {
 210     winSsh_gss_ctx *winctx = (winSsh_gss_ctx *) ctx;
 211     char *msg;
 212
 213     if (winctx == NULL) return SSH_GSS_FAILURE;
 214
 215     /* decode the error code */
 216     switch (winctx->maj_stat) {
 217       case SEC_E_OK: msg="SSPI status OK"; break;
 218       case SEC_E_INVALID_HANDLE: msg="The handle passed to the function"
 219             " is invalid.";
 220         break;
 221       case SEC_E_TARGET_UNKNOWN: msg="The target was not recognized."; break;
 222       case SEC_E_LOGON_DENIED: msg="The logon failed."; break;
 223       case SEC_E_INTERNAL_ERROR: msg="The Local Security Authority cannot"
 224             " be contacted.";
 225         break;
 226       case SEC_E_NO_CREDENTIALS: msg="No credentials are available in the"
 227             " security package.";
 228         break;
 229       case SEC_E_NO_AUTHENTICATING_AUTHORITY:
 230         msg="No authority could be contacted for authentication."
 231             "The domain name of the authenticating party could be wrong,"
 232             " the domain could be unreachable, or there might have been"
 233             " a trust relationship failure.";
 234         break;
 235       case SEC_E_INSUFFICIENT_MEMORY:
 236         msg="One or more of the SecBufferDesc structures passed as"
 237             " an OUT parameter has a buffer that is too small.";
 238         break;
 239       case SEC_E_INVALID_TOKEN:
 240         msg="The error is due to a malformed input token, such as a"
 241             " token corrupted in transit, a token"
 242             " of incorrect size, or a token passed into the wrong"
 243             " security package. Passing a token to"
 244             " the wrong package can happen if client and server did not"
 245             " negotiate the proper security package.";
 246         break;
 247       default:
 248         msg = "Internal SSPI error";
 249         break;
 250     }
 251
 252     buf->data = dupstr(msg);
 253     buf->len = strlen(buf->data);
 254
 255     return SSH_GSS_OK;
 256 }
 257
 258 Ssh_gss_stat ssh_gss_get_mic(Ssh_gss_ctx ctx, Ssh_gss_buf *buf,
 259                              Ssh_gss_buf *hash)
 260 {
 261     winSsh_gss_ctx *winctx= (winSsh_gss_ctx *) ctx;
 262     SecPkgContext_Sizes ContextSizes;
 263     SecBufferDesc InputBufferDescriptor;
 264     SecBuffer InputSecurityToken[2];
 265
 266     if (winctx == NULL) return SSH_GSS_FAILURE;
 267
 268     winctx->maj_stat = 0;
 269
 270     memset(&ContextSizes, 0, sizeof(ContextSizes));
 271
 272     winctx->maj_stat = p_QueryContextAttributesA(&winctx->context,
 273                                                  SECPKG_ATTR_SIZES,
 274                                                  &ContextSizes);
 275
 276     if (winctx->maj_stat != SEC_E_OK ||
 277         ContextSizes.cbMaxSignature == 0)
 278         return winctx->maj_stat;
 279
 280     InputBufferDescriptor.cBuffers = 2;
 281     InputBufferDescriptor.pBuffers = InputSecurityToken;
 282     InputBufferDescriptor.ulVersion = SECBUFFER_VERSION;
 283     InputSecurityToken[0].BufferType = SECBUFFER_DATA;
 284     InputSecurityToken[0].cbBuffer = buf->len;
 285     InputSecurityToken[0].pvBuffer = buf->data;
 286     InputSecurityToken[1].BufferType = SECBUFFER_TOKEN;
 287     InputSecurityToken[1].cbBuffer = ContextSizes.cbMaxSignature;
 288     InputSecurityToken[1].pvBuffer = snewn(ContextSizes.cbMaxSignature, char);
 289
 290     winctx->maj_stat = p_MakeSignature(&winctx->context,
 291                                        0,
 292                                        &InputBufferDescriptor,
 293                                        0);
 294
 295     if (winctx->maj_stat == SEC_E_OK) {
 296         hash->len = InputSecurityToken[1].cbBuffer;
 297         hash->data = InputSecurityToken[1].pvBuffer;
 298     }
 299
 300     return winctx->maj_stat;
 301 }
 302
 303 Ssh_gss_stat ssh_gss_free_mic(Ssh_gss_buf *hash)
 304 {
 305     sfree(hash->data);
 306     return SSH_GSS_OK;
 307 }
 308
 309 #else
 310
 311 /* Dummy function so this source file defines something if NO_GSSAPI
 312    is defined. */
 313
 314 int ssh_gss_init(void)
 315 {
 316     return 0;
 317 }
 318
 319 #endif