examples/openauth/openauth.c

   1 /* This is a copy of the hellolibvirt example demonstaring how to use
   2  * virConnectOpenAuth with a custom auth callback */
   3
   4 #include <stdio.h>
   5 #include <stdlib.h>
   6 #include <string.h>
   7 #include <libvirt/libvirt.h>
   8 #include <libvirt/virterror.h>
   9
  10 static void
  11 showError(virConnectPtr conn)
  12 {
  13     int ret;
  14     virErrorPtr err;
  15
  16     err = malloc(sizeof(*err));
  17     if (err == NULL) {
  18         printf("Could not allocate memory for error data\n");
  19         goto out;
  20     }
  21
  22     ret = virConnCopyLastError(conn, err);
  23
  24     switch (ret) {
  25     case 0:
  26         printf("No error found\n");
  27         break;
  28
  29     case -1:
  30         printf("Parameter error when attempting to get last error\n");
  31         break;
  32
  33     default:
  34         printf("libvirt reported: \"%s\"\n", err->message);
  35         break;
  36     }
  37
  38     virResetError(err);
  39     free(err);
  40
  41  out:
  42     return;
  43 }
  44
  45
  46 static int
  47 showHypervisorInfo(virConnectPtr conn)
  48 {
  49     int ret = 0;
  50     unsigned long hvVer, major, minor, release;
  51     const char *hvType;
  52
  53     /* virConnectGetType returns a pointer to a static string, so no
  54      * allocation or freeing is necessary; it is possible for the call
  55      * to fail if, for example, there is no connection to a
  56      * hypervisor, so check what it returns. */
  57     hvType = virConnectGetType(conn);
  58     if (hvType == NULL) {
  59         ret = 1;
  60         printf("Failed to get hypervisor type\n");
  61         showError(conn);
  62         goto out;
  63     }
  64
  65     if (virConnectGetVersion(conn, &hvVer) != 0) {
  66         ret = 1;
  67         printf("Failed to get hypervisor version\n");
  68         showError(conn);
  69         goto out;
  70     }
  71
  72     major = hvVer / 1000000;
  73     hvVer %= 1000000;
  74     minor = hvVer / 1000;
  75     release = hvVer % 1000;
  76
  77     printf("Hypervisor: \"%s\" version: %lu.%lu.%lu\n",
  78            hvType,
  79            major,
  80            minor,
  81            release);
  82
  83  out:
  84     return ret;
  85 }
  86
  87
  88 static int
  89 showDomains(virConnectPtr conn)
  90 {
  91     int ret = 0, numNames, numInactiveDomains, numActiveDomains;
  92     ssize_t i;
  93     char **nameList = NULL;
  94
  95     numActiveDomains = virConnectNumOfDomains(conn);
  96     if (numActiveDomains == -1) {
  97         ret = 1;
  98         printf("Failed to get number of active domains\n");
  99         showError(conn);
 100         goto out;
 101     }
 102
 103     numInactiveDomains = virConnectNumOfDefinedDomains(conn);
 104     if (numInactiveDomains == -1) {
 105         ret = 1;
 106         printf("Failed to get number of inactive domains\n");
 107         showError(conn);
 108         goto out;
 109     }
 110
 111     printf("There are %d active and %d inactive domains\n",
 112            numActiveDomains, numInactiveDomains);
 113
 114     nameList = malloc(sizeof(*nameList) * numInactiveDomains);
 115
 116     if (nameList == NULL) {
 117         ret = 1;
 118         printf("Could not allocate memory for list of inactive domains\n");
 119         goto out;
 120     }
 121
 122     numNames = virConnectListDefinedDomains(conn,
 123                                             nameList,
 124                                             numInactiveDomains);
 125
 126     if (numNames == -1) {
 127         ret = 1;
 128         printf("Could not get list of defined domains from hypervisor\n");
 129         showError(conn);
 130         goto out;
 131     }
 132
 133     if (numNames > 0)
 134         printf("Inactive domains:\n");
 135
 136     for (i = 0; i < numNames; i++) {
 137         printf("  %s\n", *(nameList + i));
 138         /* The API documentation doesn't say so, but the names
 139          * returned by virConnectListDefinedDomains are strdup'd and
 140          * must be freed here.  */
 141         free(*(nameList + i));
 142     }
 143
 144  out:
 145     free(nameList);
 146     return ret;
 147 }
 148
 149 /* Struct to pass the credentials to the auth callback via the cbdata pointer */
 150 struct _AuthData {
 151     char *username;
 152     char *password;
 153 };
 154
 155 typedef struct _AuthData AuthData;
 156
 157 /* This function will be called by libvirt to obtain credentials in order to
 158  * authenticate to the hypervisor */
 159 static int
 160 authCallback(virConnectCredentialPtr cred, unsigned int ncred, void *cbdata)
 161 {
 162     size_t i;
 163     AuthData *authData = cbdata;
 164
 165     /* libvirt might request multiple credentials in a single call.
 166      * This example supports VIR_CRED_AUTHNAME and VIR_CRED_PASSPHRASE
 167      * credentials only, but there are several other types.
 168      *
 169      * A request may also contain a prompt message that can be displayed
 170      * to the user and a challenge. The challenge is specific to the
 171      * credential type and hypervisor type.
 172      *
 173      * For example the ESX driver passes the hostname of the ESX or vCenter
 174      * server as challenge. This allows a auth callback to return the
 175      * proper credentials. */
 176     for (i = 0; i < ncred; ++i) {
 177         switch (cred[i].type) {
 178         case VIR_CRED_AUTHNAME:
 179             cred[i].result = strdup(authData->username);
 180
 181             if (cred[i].result == NULL)
 182                 return -1;
 183
 184             cred[i].resultlen = strlen(cred[i].result);
 185             break;
 186
 187         case VIR_CRED_PASSPHRASE:
 188             cred[i].result = strdup(authData->password);
 189
 190             if (cred[i].result == NULL)
 191                 return -1;
 192
 193             cred[i].resultlen = strlen(cred[i].result);
 194             break;
 195
 196         default:
 197             return -1;
 198         }
 199     }
 200
 201     return 0;
 202 }
 203
 204
 205 /* The list of credential types supported by our auth callback */
 206 static int credTypes[] = {
 207     VIR_CRED_AUTHNAME,
 208     VIR_CRED_PASSPHRASE
 209 };
 210
 211
 212 /* The auth struct that will be passed to virConnectOpenAuth */
 213 static virConnectAuth auth = {
 214     credTypes,
 215     sizeof(credTypes) / sizeof(int),
 216     authCallback,
 217     NULL, /* cbdata will be initialized in main */
 218 };
 219
 220
 221 int
 222 main(int argc, char *argv[])
 223 {
 224     int ret = 0;
 225     virConnectPtr conn;
 226     char *uri;
 227     AuthData authData;
 228
 229     if (argc != 4) {
 230         ret = 1;
 231         printf("Usage: %s <uri> <username> <password>\n", argv[0]);
 232         goto out;
 233     }
 234
 235     uri = argv[1];
 236     authData.username = argv[2];
 237     authData.password = argv[3];
 238     auth.cbdata = &authData;
 239
 240     printf("Attempting to connect to hypervisor\n");
 241
 242     conn = virConnectOpenAuth(uri, &auth, 0);
 243
 244     if (NULL == conn) {
 245         ret = 1;
 246         printf("No connection to hypervisor\n");
 247         showError(conn);
 248         goto out;
 249     }
 250
 251     uri = virConnectGetURI(conn);
 252     if (uri == NULL) {
 253         ret = 1;
 254         printf("Failed to get URI for hypervisor connection\n");
 255         showError(conn);
 256         goto disconnect;
 257     }
 258
 259     printf("Connected to hypervisor at \"%s\"\n", uri);
 260     free(uri);
 261
 262     if (showHypervisorInfo(conn) != 0) {
 263         ret = 1;
 264         goto disconnect;
 265     }
 266
 267     if (showDomains(conn) != 0) {
 268         ret = 1;
 269         goto disconnect;
 270     }
 271
 272  disconnect:
 273     if (virConnectClose(conn) != 0) {
 274         printf("Failed to disconnect from hypervisor\n");
 275         showError(conn);
 276         ret = 1;
 277     } else {
 278         printf("Disconnected from hypervisor\n");
 279     }
 280
 281  out:
 282     return ret;
 283 }