sshgssc.c

   1 #include "putty.h"
   2
   3 #include <string.h>
   4 #include "sshgssc.h"
   5 #include "misc.h"
   6
   7 #ifndef NO_GSSAPI
   8
   9 static Ssh_gss_stat ssh_gssapi_indicate_mech(struct ssh_gss_library *lib,
  10                                              Ssh_gss_buf *mech)
  11 {
  12     /* Copy constant into mech */
  13     mech->length  = GSS_MECH_KRB5->length;
  14     mech->value = GSS_MECH_KRB5->elements;
  15     return SSH_GSS_OK;
  16 }
  17
  18 static Ssh_gss_stat ssh_gssapi_import_name(struct ssh_gss_library *lib,
  19                                            char *host,
  20                                            Ssh_gss_name *srv_name)
  21 {
  22     struct gssapi_functions *gss = &lib->u.gssapi;
  23     OM_uint32 min_stat,maj_stat;
  24     gss_buffer_desc host_buf;
  25     char *pStr;
  26
  27     pStr = dupcat("host@", host, NULL);
  28
  29     host_buf.value = pStr;
  30     host_buf.length = strlen(pStr);
  31
  32     maj_stat = gss->import_name(&min_stat, &host_buf,
  33                                 GSS_C_NT_HOSTBASED_SERVICE, srv_name);
  34     /* Release buffer */
  35     sfree(pStr);
  36     if (maj_stat == GSS_S_COMPLETE) return SSH_GSS_OK;
  37     return SSH_GSS_FAILURE;
  38 }
  39
  40 static Ssh_gss_stat ssh_gssapi_acquire_cred(struct ssh_gss_library *lib,
  41                                             Ssh_gss_ctx *ctx)
  42 {
  43     gssapi_ssh_gss_ctx *gssctx = snew(gssapi_ssh_gss_ctx);
  44
  45     gssctx->maj_stat =  gssctx->min_stat = GSS_S_COMPLETE;
  46     gssctx->ctx = GSS_C_NO_CONTEXT;
  47     *ctx = (Ssh_gss_ctx) gssctx;
  48
  49     return SSH_GSS_OK;
  50 }
  51
  52 static Ssh_gss_stat ssh_gssapi_init_sec_context(struct ssh_gss_library *lib,
  53                                                 Ssh_gss_ctx *ctx,
  54                                                 Ssh_gss_name srv_name,
  55                                                 int to_deleg,
  56                                                 Ssh_gss_buf *recv_tok,
  57                                                 Ssh_gss_buf *send_tok)
  58 {
  59     struct gssapi_functions *gss = &lib->u.gssapi;
  60     gssapi_ssh_gss_ctx *gssctx = (gssapi_ssh_gss_ctx*) *ctx;
  61     OM_uint32 ret_flags;
  62
  63     if (to_deleg) to_deleg = GSS_C_DELEG_FLAG;
  64     gssctx->maj_stat = gss->init_sec_context(&gssctx->min_stat,
  65                                              GSS_C_NO_CREDENTIAL,
  66                                              &gssctx->ctx,
  67                                              srv_name,
  68                                              (gss_OID) GSS_MECH_KRB5,
  69                                              GSS_C_MUTUAL_FLAG |
  70                                              GSS_C_INTEG_FLAG | to_deleg,
  71                                              0,
  72                                              GSS_C_NO_CHANNEL_BINDINGS,
  73                                              recv_tok,
  74                                              NULL,   /* ignore mech type */
  75                                              send_tok,
  76                                              &ret_flags,
  77                                              NULL);  /* ignore time_rec */
  78
  79     if (gssctx->maj_stat == GSS_S_COMPLETE) return SSH_GSS_S_COMPLETE;
  80     if (gssctx->maj_stat == GSS_S_CONTINUE_NEEDED) return SSH_GSS_S_CONTINUE_NEEDED;
  81     return SSH_GSS_FAILURE;
  82 }
  83
  84 static Ssh_gss_stat ssh_gssapi_display_status(struct ssh_gss_library *lib,
  85                                               Ssh_gss_ctx ctx,
  86                                               Ssh_gss_buf *buf)
  87 {
  88     struct gssapi_functions *gss = &lib->u.gssapi;
  89     gssapi_ssh_gss_ctx *gssctx = (gssapi_ssh_gss_ctx *) ctx;
  90     OM_uint32 lmin,lmax;
  91     OM_uint32 ccc;
  92     gss_buffer_desc msg_maj=GSS_C_EMPTY_BUFFER;
  93     gss_buffer_desc msg_min=GSS_C_EMPTY_BUFFER;
  94
  95     /* Return empty buffer in case of failure */
  96     SSH_GSS_CLEAR_BUF(buf);
  97
  98     /* get first mesg from GSS */
  99     ccc=0;
 100     lmax=gss->display_status(&lmin,gssctx->maj_stat,GSS_C_GSS_CODE,(gss_OID) GSS_MECH_KRB5,&ccc,&msg_maj);
 101
 102     if (lmax != GSS_S_COMPLETE) return SSH_GSS_FAILURE;
 103
 104     /* get first mesg from Kerberos */
 105     ccc=0;
 106     lmax=gss->display_status(&lmin,gssctx->min_stat,GSS_C_MECH_CODE,(gss_OID) GSS_MECH_KRB5,&ccc,&msg_min);
 107
 108     if (lmax != GSS_S_COMPLETE) {
 109         gss->release_buffer(&lmin, &msg_maj);
 110         return SSH_GSS_FAILURE;
 111     }
 112
 113     /* copy data into buffer */
 114     buf->length = msg_maj.length + msg_min.length + 1;
 115     buf->value = snewn(buf->length + 1, char);
 116
 117     /* copy mem */
 118     memcpy((char *)buf->value, msg_maj.value, msg_maj.length);
 119     ((char *)buf->value)[msg_maj.length] = ' ';
 120     memcpy((char *)buf->value + msg_maj.length + 1, msg_min.value, msg_min.length);
 121     ((char *)buf->value)[buf->length] = 0;
 122     /* free mem & exit */
 123     gss->release_buffer(&lmin, &msg_maj);
 124     gss->release_buffer(&lmin, &msg_min);
 125     return SSH_GSS_OK;
 126 }
 127
 128 static Ssh_gss_stat ssh_gssapi_free_tok(struct ssh_gss_library *lib,
 129                                         Ssh_gss_buf *send_tok)
 130 {
 131     struct gssapi_functions *gss = &lib->u.gssapi;
 132     OM_uint32 min_stat,maj_stat;
 133     maj_stat = gss->release_buffer(&min_stat, send_tok);
 134
 135     if (maj_stat == GSS_S_COMPLETE) return SSH_GSS_OK;
 136     return SSH_GSS_FAILURE;
 137 }
 138
 139 static Ssh_gss_stat ssh_gssapi_release_cred(struct ssh_gss_library *lib,
 140                                             Ssh_gss_ctx *ctx)
 141 {
 142     struct gssapi_functions *gss = &lib->u.gssapi;
 143     gssapi_ssh_gss_ctx *gssctx = (gssapi_ssh_gss_ctx *) *ctx;
 144     OM_uint32 min_stat;
 145     OM_uint32 maj_stat=GSS_S_COMPLETE;
 146
 147     if (gssctx == NULL) return SSH_GSS_FAILURE;
 148     if (gssctx->ctx != GSS_C_NO_CONTEXT)
 149         maj_stat = gss->delete_sec_context(&min_stat,&gssctx->ctx,GSS_C_NO_BUFFER);
 150     sfree(gssctx);
 151
 152     if (maj_stat == GSS_S_COMPLETE) return SSH_GSS_OK;
 153     return SSH_GSS_FAILURE;
 154 }
 155
 156
 157 static Ssh_gss_stat ssh_gssapi_release_name(struct ssh_gss_library *lib,
 158                                             Ssh_gss_name *srv_name)
 159 {
 160     struct gssapi_functions *gss = &lib->u.gssapi;
 161     OM_uint32 min_stat,maj_stat;
 162     maj_stat = gss->release_name(&min_stat, srv_name);
 163
 164     if (maj_stat == GSS_S_COMPLETE) return SSH_GSS_OK;
 165     return SSH_GSS_FAILURE;
 166 }
 167
 168 static Ssh_gss_stat ssh_gssapi_get_mic(struct ssh_gss_library *lib,
 169                                        Ssh_gss_ctx ctx, Ssh_gss_buf *buf,
 170                                        Ssh_gss_buf *hash)
 171 {
 172     struct gssapi_functions *gss = &lib->u.gssapi;
 173     gssapi_ssh_gss_ctx *gssctx = (gssapi_ssh_gss_ctx *) ctx;
 174     if (gssctx == NULL) return SSH_GSS_FAILURE;
 175     return gss->get_mic(&(gssctx->min_stat), gssctx->ctx, 0, buf, hash);
 176 }
 177
 178 static Ssh_gss_stat ssh_gssapi_free_mic(struct ssh_gss_library *lib,
 179                                         Ssh_gss_buf *hash)
 180 {
 181     /* On Unix this is the same freeing process as ssh_gssapi_free_tok. */
 182     return ssh_gssapi_free_tok(lib, hash);
 183 }
 184
 185 void ssh_gssapi_bind_fns(struct ssh_gss_library *lib)
 186 {
 187     lib->indicate_mech = ssh_gssapi_indicate_mech;
 188     lib->import_name = ssh_gssapi_import_name;
 189     lib->release_name = ssh_gssapi_release_name;
 190     lib->init_sec_context = ssh_gssapi_init_sec_context;
 191     lib->free_tok = ssh_gssapi_free_tok;
 192     lib->acquire_cred = ssh_gssapi_acquire_cred;
 193     lib->release_cred = ssh_gssapi_release_cred;
 194     lib->get_mic = ssh_gssapi_get_mic;
 195     lib->free_mic = ssh_gssapi_free_mic;
 196     lib->display_status = ssh_gssapi_display_status;
 197 }
 198
 199 #else
 200
 201 /* Dummy function so this source file defines something if NO_GSSAPI
 202    is defined. */
 203
 204 int ssh_gssapi_init(void)
 205 {
 206     return 0;
 207 }
 208
 209 #endif