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      1 /***************************************************************************
      2  *                                  _   _ ____  _
      3  *  Project                     ___| | | |  _ \| |
      4  *                             / __| | | | |_) | |
      5  *                            | (__| |_| |  _ <| |___
      6  *                             \___|\___/|_| \_\_____|
      7  *
      8  * Copyright (C) 2012 - 2016, Daniel Stenberg, <daniel (at) haxx.se>, et al.
      9  *
     10  * This software is licensed as described in the file COPYING, which
     11  * you should have received as part of this distribution. The terms
     12  * are also available at https://curl.haxx.se/docs/copyright.html.
     13  *
     14  * You may opt to use, copy, modify, merge, publish, distribute and/or sell
     15  * copies of the Software, and permit persons to whom the Software is
     16  * furnished to do so, under the terms of the COPYING file.
     17  *
     18  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
     19  * KIND, either express or implied.
     20  *
     21  * RFC2195 CRAM-MD5 authentication
     22  * RFC2617 Basic and Digest Access Authentication
     23  * RFC2831 DIGEST-MD5 authentication
     24  * RFC4422 Simple Authentication and Security Layer (SASL)
     25  * RFC4616 PLAIN authentication
     26  * RFC6749 OAuth 2.0 Authorization Framework
     27  * RFC7628 A Set of SASL Mechanisms for OAuth
     28  * Draft   LOGIN SASL Mechanism <draft-murchison-sasl-login-00.txt>
     29  *
     30  ***************************************************************************/
     31 
     32 #include "curl_setup.h"
     33 
     34 #include <curl/curl.h>
     35 #include "urldata.h"
     36 
     37 #include "curl_base64.h"
     38 #include "curl_md5.h"
     39 #include "vauth/vauth.h"
     40 #include "vtls/vtls.h"
     41 #include "curl_hmac.h"
     42 #include "curl_sasl.h"
     43 #include "warnless.h"
     44 #include "strtok.h"
     45 #include "sendf.h"
     46 #include "non-ascii.h" /* included for Curl_convert_... prototypes */
     47 /* The last 3 #include files should be in this order */
     48 #include "curl_printf.h"
     49 #include "curl_memory.h"
     50 #include "memdebug.h"
     51 
     52 /* Supported mechanisms */
     53 const struct {
     54   const char   *name;  /* Name */
     55   size_t        len;   /* Name length */
     56   unsigned int  bit;   /* Flag bit */
     57 } mechtable[] = {
     58   { "LOGIN",        5,  SASL_MECH_LOGIN },
     59   { "PLAIN",        5,  SASL_MECH_PLAIN },
     60   { "CRAM-MD5",     8,  SASL_MECH_CRAM_MD5 },
     61   { "DIGEST-MD5",   10, SASL_MECH_DIGEST_MD5 },
     62   { "GSSAPI",       6,  SASL_MECH_GSSAPI },
     63   { "EXTERNAL",     8,  SASL_MECH_EXTERNAL },
     64   { "NTLM",         4,  SASL_MECH_NTLM },
     65   { "XOAUTH2",      7,  SASL_MECH_XOAUTH2 },
     66   { "OAUTHBEARER",  11, SASL_MECH_OAUTHBEARER },
     67   { ZERO_NULL,      0,  0 }
     68 };
     69 
     70 /*
     71  * Curl_sasl_cleanup()
     72  *
     73  * This is used to cleanup any libraries or curl modules used by the sasl
     74  * functions.
     75  *
     76  * Parameters:
     77  *
     78  * conn     [in]     - The connection data.
     79  * authused [in]     - The authentication mechanism used.
     80  */
     81 void Curl_sasl_cleanup(struct connectdata *conn, unsigned int authused)
     82 {
     83 #if defined(USE_KERBEROS5)
     84   /* Cleanup the gssapi structure */
     85   if(authused == SASL_MECH_GSSAPI) {
     86     Curl_auth_gssapi_cleanup(&conn->krb5);
     87   }
     88 #endif
     89 
     90 #if defined(USE_NTLM)
     91   /* Cleanup the NTLM structure */
     92   if(authused == SASL_MECH_NTLM) {
     93     Curl_auth_ntlm_cleanup(&conn->ntlm);
     94   }
     95 #endif
     96 
     97 #if !defined(USE_KERBEROS5) && !defined(USE_NTLM)
     98   /* Reserved for future use */
     99   (void)conn;
    100   (void)authused;
    101 #endif
    102 }
    103 
    104 /*
    105  * Curl_sasl_decode_mech()
    106  *
    107  * Convert a SASL mechanism name into a token.
    108  *
    109  * Parameters:
    110  *
    111  * ptr    [in]     - The mechanism string.
    112  * maxlen [in]     - Maximum mechanism string length.
    113  * len    [out]    - If not NULL, effective name length.
    114  *
    115  * Returns the SASL mechanism token or 0 if no match.
    116  */
    117 unsigned int Curl_sasl_decode_mech(const char *ptr, size_t maxlen, size_t *len)
    118 {
    119   unsigned int i;
    120   char c;
    121 
    122   for(i = 0; mechtable[i].name; i++) {
    123     if(maxlen >= mechtable[i].len &&
    124        !memcmp(ptr, mechtable[i].name, mechtable[i].len)) {
    125       if(len)
    126         *len = mechtable[i].len;
    127 
    128       if(maxlen == mechtable[i].len)
    129         return mechtable[i].bit;
    130 
    131       c = ptr[mechtable[i].len];
    132       if(!ISUPPER(c) && !ISDIGIT(c) && c != '-' && c != '_')
    133         return mechtable[i].bit;
    134     }
    135   }
    136 
    137   return 0;
    138 }
    139 
    140 /*
    141  * Curl_sasl_parse_url_auth_option()
    142  *
    143  * Parse the URL login options.
    144  */
    145 CURLcode Curl_sasl_parse_url_auth_option(struct SASL *sasl,
    146                                          const char *value, size_t len)
    147 {
    148   CURLcode result = CURLE_OK;
    149   unsigned int mechbit;
    150   size_t mechlen;
    151 
    152   if(!len)
    153     return CURLE_URL_MALFORMAT;
    154 
    155   if(sasl->resetprefs) {
    156     sasl->resetprefs = FALSE;
    157     sasl->prefmech = SASL_AUTH_NONE;
    158   }
    159 
    160   if(!strncmp(value, "*", len))
    161     sasl->prefmech = SASL_AUTH_DEFAULT;
    162   else {
    163     mechbit = Curl_sasl_decode_mech(value, len, &mechlen);
    164     if(mechbit && mechlen == len)
    165       sasl->prefmech |= mechbit;
    166     else
    167       result = CURLE_URL_MALFORMAT;
    168   }
    169 
    170   return result;
    171 }
    172 
    173 /*
    174  * Curl_sasl_init()
    175  *
    176  * Initializes the SASL structure.
    177  */
    178 void Curl_sasl_init(struct SASL *sasl, const struct SASLproto *params)
    179 {
    180   sasl->params = params;           /* Set protocol dependent parameters */
    181   sasl->state = SASL_STOP;         /* Not yet running */
    182   sasl->authmechs = SASL_AUTH_NONE; /* No known authentication mechanism yet */
    183   sasl->prefmech = SASL_AUTH_DEFAULT; /* Prefer all mechanisms */
    184   sasl->authused = SASL_AUTH_NONE; /* No the authentication mechanism used */
    185   sasl->resetprefs = TRUE;         /* Reset prefmech upon AUTH parsing. */
    186   sasl->mutual_auth = FALSE;       /* No mutual authentication (GSSAPI only) */
    187   sasl->force_ir = FALSE;          /* Respect external option */
    188 }
    189 
    190 /*
    191  * state()
    192  *
    193  * This is the ONLY way to change SASL state!
    194  */
    195 static void state(struct SASL *sasl, struct connectdata *conn,
    196                   saslstate newstate)
    197 {
    198 #if defined(DEBUGBUILD) && !defined(CURL_DISABLE_VERBOSE_STRINGS)
    199   /* for debug purposes */
    200   static const char * const names[]={
    201     "STOP",
    202     "PLAIN",
    203     "LOGIN",
    204     "LOGIN_PASSWD",
    205     "EXTERNAL",
    206     "CRAMMD5",
    207     "DIGESTMD5",
    208     "DIGESTMD5_RESP",
    209     "NTLM",
    210     "NTLM_TYPE2MSG",
    211     "GSSAPI",
    212     "GSSAPI_TOKEN",
    213     "GSSAPI_NO_DATA",
    214     "OAUTH2",
    215     "OAUTH2_RESP",
    216     "CANCEL",
    217     "FINAL",
    218     /* LAST */
    219   };
    220 
    221   if(sasl->state != newstate)
    222     infof(conn->data, "SASL %p state change from %s to %s\n",
    223           (void *)sasl, names[sasl->state], names[newstate]);
    224 #else
    225   (void) conn;
    226 #endif
    227 
    228   sasl->state = newstate;
    229 }
    230 
    231 /*
    232  * Curl_sasl_can_authenticate()
    233  *
    234  * Check if we have enough auth data and capabilities to authenticate.
    235  */
    236 bool Curl_sasl_can_authenticate(struct SASL *sasl, struct connectdata *conn)
    237 {
    238   /* Have credentials been provided? */
    239   if(conn->bits.user_passwd)
    240     return TRUE;
    241 
    242   /* EXTERNAL can authenticate without a user name and/or password */
    243   if(sasl->authmechs & sasl->prefmech & SASL_MECH_EXTERNAL)
    244     return TRUE;
    245 
    246   return FALSE;
    247 }
    248 
    249 /*
    250  * Curl_sasl_start()
    251  *
    252  * Calculate the required login details for SASL authentication.
    253  */
    254 CURLcode Curl_sasl_start(struct SASL *sasl, struct connectdata *conn,
    255                          bool force_ir, saslprogress *progress)
    256 {
    257   CURLcode result = CURLE_OK;
    258   struct Curl_easy *data = conn->data;
    259   unsigned int enabledmechs;
    260   const char *mech = NULL;
    261   char *resp = NULL;
    262   size_t len = 0;
    263   saslstate state1 = SASL_STOP;
    264   saslstate state2 = SASL_FINAL;
    265   const char * const hostname = SSL_IS_PROXY() ? conn->http_proxy.host.name :
    266     conn->host.name;
    267   const long int port = SSL_IS_PROXY() ? conn->port : conn->remote_port;
    268 #if defined(USE_KERBEROS5)
    269   const char *service = data->set.str[STRING_SERVICE_NAME] ?
    270     data->set.str[STRING_SERVICE_NAME] :
    271     sasl->params->service;
    272 #endif
    273 
    274   sasl->force_ir = force_ir;    /* Latch for future use */
    275   sasl->authused = 0;           /* No mechanism used yet */
    276   enabledmechs = sasl->authmechs & sasl->prefmech;
    277   *progress = SASL_IDLE;
    278 
    279   /* Calculate the supported authentication mechanism, by decreasing order of
    280      security, as well as the initial response where appropriate */
    281   if((enabledmechs & SASL_MECH_EXTERNAL) && !conn->passwd[0]) {
    282     mech = SASL_MECH_STRING_EXTERNAL;
    283     state1 = SASL_EXTERNAL;
    284     sasl->authused = SASL_MECH_EXTERNAL;
    285 
    286     if(force_ir || data->set.sasl_ir)
    287       result = Curl_auth_create_external_message(data, conn->user, &resp,
    288                                                  &len);
    289   }
    290   else if(conn->bits.user_passwd) {
    291 #if defined(USE_KERBEROS5)
    292     if((enabledmechs & SASL_MECH_GSSAPI) && Curl_auth_is_gssapi_supported() &&
    293        Curl_auth_user_contains_domain(conn->user)) {
    294       sasl->mutual_auth = FALSE; /* TODO: Calculate mutual authentication */
    295       mech = SASL_MECH_STRING_GSSAPI;
    296       state1 = SASL_GSSAPI;
    297       state2 = SASL_GSSAPI_TOKEN;
    298       sasl->authused = SASL_MECH_GSSAPI;
    299 
    300       if(force_ir || data->set.sasl_ir)
    301         result = Curl_auth_create_gssapi_user_message(data, conn->user,
    302                                                       conn->passwd,
    303                                                       service,
    304                                                       data->easy_conn->
    305                                                             host.name,
    306                                                       sasl->mutual_auth,
    307                                                       NULL, &conn->krb5,
    308                                                       &resp, &len);
    309     }
    310     else
    311 #endif
    312 #ifndef CURL_DISABLE_CRYPTO_AUTH
    313     if((enabledmechs & SASL_MECH_DIGEST_MD5) &&
    314        Curl_auth_is_digest_supported()) {
    315       mech = SASL_MECH_STRING_DIGEST_MD5;
    316       state1 = SASL_DIGESTMD5;
    317       sasl->authused = SASL_MECH_DIGEST_MD5;
    318     }
    319     else if(enabledmechs & SASL_MECH_CRAM_MD5) {
    320       mech = SASL_MECH_STRING_CRAM_MD5;
    321       state1 = SASL_CRAMMD5;
    322       sasl->authused = SASL_MECH_CRAM_MD5;
    323     }
    324     else
    325 #endif
    326 #ifdef USE_NTLM
    327     if((enabledmechs & SASL_MECH_NTLM) && Curl_auth_is_ntlm_supported()) {
    328       mech = SASL_MECH_STRING_NTLM;
    329       state1 = SASL_NTLM;
    330       state2 = SASL_NTLM_TYPE2MSG;
    331       sasl->authused = SASL_MECH_NTLM;
    332 
    333       if(force_ir || data->set.sasl_ir)
    334         result = Curl_auth_create_ntlm_type1_message(conn->user, conn->passwd,
    335                                                      &conn->ntlm, &resp, &len);
    336       }
    337     else
    338 #endif
    339     if((enabledmechs & SASL_MECH_OAUTHBEARER) && conn->oauth_bearer) {
    340       mech = SASL_MECH_STRING_OAUTHBEARER;
    341       state1 = SASL_OAUTH2;
    342       state2 = SASL_OAUTH2_RESP;
    343       sasl->authused = SASL_MECH_OAUTHBEARER;
    344 
    345       if(force_ir || data->set.sasl_ir)
    346         result = Curl_auth_create_oauth_bearer_message(data, conn->user,
    347                                                        hostname,
    348                                                        port,
    349                                                        conn->oauth_bearer,
    350                                                        &resp, &len);
    351     }
    352     else if((enabledmechs & SASL_MECH_XOAUTH2) && conn->oauth_bearer) {
    353       mech = SASL_MECH_STRING_XOAUTH2;
    354       state1 = SASL_OAUTH2;
    355       sasl->authused = SASL_MECH_XOAUTH2;
    356 
    357       if(force_ir || data->set.sasl_ir)
    358         result = Curl_auth_create_oauth_bearer_message(data, conn->user,
    359                                                        NULL, 0,
    360                                                        conn->oauth_bearer,
    361                                                        &resp, &len);
    362     }
    363     else if(enabledmechs & SASL_MECH_LOGIN) {
    364       mech = SASL_MECH_STRING_LOGIN;
    365       state1 = SASL_LOGIN;
    366       state2 = SASL_LOGIN_PASSWD;
    367       sasl->authused = SASL_MECH_LOGIN;
    368 
    369       if(force_ir || data->set.sasl_ir)
    370         result = Curl_auth_create_login_message(data, conn->user, &resp, &len);
    371     }
    372     else if(enabledmechs & SASL_MECH_PLAIN) {
    373       mech = SASL_MECH_STRING_PLAIN;
    374       state1 = SASL_PLAIN;
    375       sasl->authused = SASL_MECH_PLAIN;
    376 
    377       if(force_ir || data->set.sasl_ir)
    378         result = Curl_auth_create_plain_message(data, conn->user, conn->passwd,
    379                                                 &resp, &len);
    380     }
    381   }
    382 
    383   if(!result && mech) {
    384     if(resp && sasl->params->maxirlen &&
    385        strlen(mech) + len > sasl->params->maxirlen) {
    386       free(resp);
    387       resp = NULL;
    388     }
    389 
    390     result = sasl->params->sendauth(conn, mech, resp);
    391     if(!result) {
    392       *progress = SASL_INPROGRESS;
    393       state(sasl, conn, resp ? state2 : state1);
    394     }
    395   }
    396 
    397   free(resp);
    398 
    399   return result;
    400 }
    401 
    402 /*
    403  * Curl_sasl_continue()
    404  *
    405  * Continue the authentication.
    406  */
    407 CURLcode Curl_sasl_continue(struct SASL *sasl, struct connectdata *conn,
    408                             int code, saslprogress *progress)
    409 {
    410   CURLcode result = CURLE_OK;
    411   struct Curl_easy *data = conn->data;
    412   saslstate newstate = SASL_FINAL;
    413   char *resp = NULL;
    414   const char * const hostname = SSL_IS_PROXY() ? conn->http_proxy.host.name :
    415     conn->host.name;
    416   const long int port = SSL_IS_PROXY() ? conn->port : conn->remote_port;
    417 #if !defined(CURL_DISABLE_CRYPTO_AUTH)
    418   char *serverdata;
    419   char *chlg = NULL;
    420   size_t chlglen = 0;
    421 #endif
    422 #if !defined(CURL_DISABLE_CRYPTO_AUTH) || defined(USE_KERBEROS5)
    423   const char *service = data->set.str[STRING_SERVICE_NAME] ?
    424                         data->set.str[STRING_SERVICE_NAME] :
    425                         sasl->params->service;
    426 #endif
    427   size_t len = 0;
    428 
    429   *progress = SASL_INPROGRESS;
    430 
    431   if(sasl->state == SASL_FINAL) {
    432     if(code != sasl->params->finalcode)
    433       result = CURLE_LOGIN_DENIED;
    434     *progress = SASL_DONE;
    435     state(sasl, conn, SASL_STOP);
    436     return result;
    437   }
    438 
    439   if(sasl->state != SASL_CANCEL && sasl->state != SASL_OAUTH2_RESP &&
    440      code != sasl->params->contcode) {
    441     *progress = SASL_DONE;
    442     state(sasl, conn, SASL_STOP);
    443     return CURLE_LOGIN_DENIED;
    444   }
    445 
    446   switch(sasl->state) {
    447   case SASL_STOP:
    448     *progress = SASL_DONE;
    449     return result;
    450   case SASL_PLAIN:
    451     result = Curl_auth_create_plain_message(data, conn->user, conn->passwd,
    452                                             &resp,
    453                                             &len);
    454     break;
    455   case SASL_LOGIN:
    456     result = Curl_auth_create_login_message(data, conn->user, &resp, &len);
    457     newstate = SASL_LOGIN_PASSWD;
    458     break;
    459   case SASL_LOGIN_PASSWD:
    460     result = Curl_auth_create_login_message(data, conn->passwd, &resp, &len);
    461     break;
    462   case SASL_EXTERNAL:
    463     result = Curl_auth_create_external_message(data, conn->user, &resp, &len);
    464     break;
    465 
    466 #ifndef CURL_DISABLE_CRYPTO_AUTH
    467   case SASL_CRAMMD5:
    468     sasl->params->getmessage(data->state.buffer, &serverdata);
    469     result = Curl_auth_decode_cram_md5_message(serverdata, &chlg, &chlglen);
    470     if(!result)
    471       result = Curl_auth_create_cram_md5_message(data, chlg, conn->user,
    472                                                  conn->passwd, &resp, &len);
    473     free(chlg);
    474     break;
    475   case SASL_DIGESTMD5:
    476     sasl->params->getmessage(data->state.buffer, &serverdata);
    477     result = Curl_auth_create_digest_md5_message(data, serverdata,
    478                                                  conn->user, conn->passwd,
    479                                                  service,
    480                                                  &resp, &len);
    481     newstate = SASL_DIGESTMD5_RESP;
    482     break;
    483   case SASL_DIGESTMD5_RESP:
    484     resp = strdup("");
    485     if(!resp)
    486       result = CURLE_OUT_OF_MEMORY;
    487     break;
    488 #endif
    489 
    490 #ifdef USE_NTLM
    491   case SASL_NTLM:
    492     /* Create the type-1 message */
    493     result = Curl_auth_create_ntlm_type1_message(conn->user, conn->passwd,
    494                                                  &conn->ntlm, &resp, &len);
    495     newstate = SASL_NTLM_TYPE2MSG;
    496     break;
    497   case SASL_NTLM_TYPE2MSG:
    498     /* Decode the type-2 message */
    499     sasl->params->getmessage(data->state.buffer, &serverdata);
    500     result = Curl_auth_decode_ntlm_type2_message(data, serverdata,
    501                                                  &conn->ntlm);
    502     if(!result)
    503       result = Curl_auth_create_ntlm_type3_message(data, conn->user,
    504                                                    conn->passwd, &conn->ntlm,
    505                                                    &resp, &len);
    506     break;
    507 #endif
    508 
    509 #if defined(USE_KERBEROS5)
    510   case SASL_GSSAPI:
    511     result = Curl_auth_create_gssapi_user_message(data, conn->user,
    512                                                   conn->passwd,
    513                                                   service,
    514                                                   data->easy_conn->host.name,
    515                                                   sasl->mutual_auth, NULL,
    516                                                   &conn->krb5,
    517                                                   &resp, &len);
    518     newstate = SASL_GSSAPI_TOKEN;
    519     break;
    520   case SASL_GSSAPI_TOKEN:
    521     sasl->params->getmessage(data->state.buffer, &serverdata);
    522     if(sasl->mutual_auth) {
    523       /* Decode the user token challenge and create the optional response
    524          message */
    525       result = Curl_auth_create_gssapi_user_message(data, NULL, NULL,
    526                                                     NULL, NULL,
    527                                                     sasl->mutual_auth,
    528                                                     serverdata, &conn->krb5,
    529                                                     &resp, &len);
    530       newstate = SASL_GSSAPI_NO_DATA;
    531     }
    532     else
    533       /* Decode the security challenge and create the response message */
    534       result = Curl_auth_create_gssapi_security_message(data, serverdata,
    535                                                         &conn->krb5,
    536                                                         &resp, &len);
    537     break;
    538   case SASL_GSSAPI_NO_DATA:
    539     sasl->params->getmessage(data->state.buffer, &serverdata);
    540     /* Decode the security challenge and create the response message */
    541     result = Curl_auth_create_gssapi_security_message(data, serverdata,
    542                                                       &conn->krb5,
    543                                                       &resp, &len);
    544     break;
    545 #endif
    546 
    547   case SASL_OAUTH2:
    548     /* Create the authorisation message */
    549     if(sasl->authused == SASL_MECH_OAUTHBEARER) {
    550       result = Curl_auth_create_oauth_bearer_message(data, conn->user,
    551                                                      hostname,
    552                                                      port,
    553                                                      conn->oauth_bearer,
    554                                                      &resp, &len);
    555 
    556       /* Failures maybe sent by the server as continuations for OAUTHBEARER */
    557       newstate = SASL_OAUTH2_RESP;
    558     }
    559     else
    560       result = Curl_auth_create_oauth_bearer_message(data, conn->user,
    561                                                      NULL, 0,
    562                                                      conn->oauth_bearer,
    563                                                      &resp, &len);
    564     break;
    565 
    566   case SASL_OAUTH2_RESP:
    567     /* The continuation is optional so check the response code */
    568     if(code == sasl->params->finalcode) {
    569       /* Final response was received so we are done */
    570       *progress = SASL_DONE;
    571       state(sasl, conn, SASL_STOP);
    572       return result;
    573     }
    574     else if(code == sasl->params->contcode) {
    575       /* Acknowledge the continuation by sending a 0x01 response base64
    576          encoded */
    577       resp = strdup("AQ==");
    578       if(!resp)
    579         result = CURLE_OUT_OF_MEMORY;
    580       break;
    581     }
    582     else {
    583       *progress = SASL_DONE;
    584       state(sasl, conn, SASL_STOP);
    585       return CURLE_LOGIN_DENIED;
    586     }
    587 
    588   case SASL_CANCEL:
    589     /* Remove the offending mechanism from the supported list */
    590     sasl->authmechs ^= sasl->authused;
    591 
    592     /* Start an alternative SASL authentication */
    593     result = Curl_sasl_start(sasl, conn, sasl->force_ir, progress);
    594     newstate = sasl->state;   /* Use state from Curl_sasl_start() */
    595     break;
    596   default:
    597     failf(data, "Unsupported SASL authentication mechanism");
    598     result = CURLE_UNSUPPORTED_PROTOCOL;  /* Should not happen */
    599     break;
    600   }
    601 
    602   switch(result) {
    603   case CURLE_BAD_CONTENT_ENCODING:
    604     /* Cancel dialog */
    605     result = sasl->params->sendcont(conn, "*");
    606     newstate = SASL_CANCEL;
    607     break;
    608   case CURLE_OK:
    609     if(resp)
    610       result = sasl->params->sendcont(conn, resp);
    611     break;
    612   default:
    613     newstate = SASL_STOP;    /* Stop on error */
    614     *progress = SASL_DONE;
    615     break;
    616   }
    617 
    618   free(resp);
    619 
    620   state(sasl, conn, newstate);
    621 
    622   return result;
    623 }
    624