sasl: binary messages

Capabilities of sasl module are extended to exchange messages in binary
as an alternative to base64.

If http authentication flags have been set, those are used as sasl
default preferred mechanisms.

Closes #6930

1 files changed, 82 insertions, 72 deletions

diff --git a/lib/imap.c b/lib/imap.c
index 6163899bb..e1704b299 100644
--- a/lib/imap.c
+++ b/lib/imap.c
@@ -78,6 +78,7 @@
 #include "multiif.h"
 #include "url.h"
 #include "strcase.h"
+#include "bufref.h"
 #include "curl_sasl.h"
 #include "warnless.h"
 
@@ -101,19 +102,19 @@ static CURLcode imap_doing(struct Curl_easy *data, bool *dophase_done);
 static CURLcode imap_setup_connection(struct Curl_easy *data,
                                       struct connectdata *conn);
 static char *imap_atom(const char *str, bool escape_only);
-static CURLcode imap_sendf(struct Curl_easy *data,
-                           struct connectdata *conn, const char *fmt, ...);
+static CURLcode imap_sendf(struct Curl_easy *data, const char *fmt, ...);
 static CURLcode imap_parse_url_options(struct connectdata *conn);
 static CURLcode imap_parse_url_path(struct Curl_easy *data);
 static CURLcode imap_parse_custom_request(struct Curl_easy *data);
 static CURLcode imap_perform_authenticate(struct Curl_easy *data,
-                                          struct connectdata *conn,
                                           const char *mech,
-                                          const char *initresp);
+                                          const struct bufref *initresp);
 static CURLcode imap_continue_authenticate(struct Curl_easy *data,
-                                           struct connectdata *conn,
-                                           const char *resp);
-static void imap_get_message(char *buffer, char **outptr);
+                                           const char *mech,
+                                           const struct bufref *resp);
+static CURLcode imap_cancel_authenticate(struct Curl_easy *data,
+                                         const char *mech);
+static CURLcode imap_get_message(struct Curl_easy *data, struct bufref *out);
 
 /*
  * IMAP protocol handler.
@@ -180,12 +181,15 @@ const struct Curl_handler Curl_handler_imaps = {
 /* SASL parameters for the imap protocol */
 static const struct SASLproto saslimap = {
   "imap",                     /* The service name */
-  '+',                        /* Code received when continuation is expected */
-  IMAP_RESP_OK,               /* Code to receive upon authentication success */
-  0,                          /* Maximum initial response length (no max) */
   imap_perform_authenticate,  /* Send authentication command */
   imap_continue_authenticate, /* Send authentication continuation */
-  imap_get_message            /* Get SASL response message */
+  imap_cancel_authenticate,   /* Send authentication cancellation */
+  imap_get_message,           /* Get SASL response message */
+  0,                          /* No maximum initial response length */
+  '+',                        /* Code received when continuation is expected */
+  IMAP_RESP_OK,               /* Code to receive upon authentication success */
+  SASL_AUTH_DEFAULT,          /* Default mechanisms */
+  SASL_FLAG_BASE64            /* Configuration flags */
 };
 
 
@@ -352,34 +356,32 @@ static bool imap_endofresp(struct Curl_easy *data, struct connectdata *conn,
  *
  * Gets the authentication message from the response buffer.
  */
-static void imap_get_message(char *buffer, char **outptr)
+static CURLcode imap_get_message(struct Curl_easy *data, struct bufref *out)
 {
-  size_t len = strlen(buffer);
-  char *message = NULL;
+  char *message = data->state.buffer;
+  size_t len = strlen(message);
 
   if(len > 2) {
     /* Find the start of the message */
     len -= 2;
-    for(message = buffer + 2; *message == ' ' || *message == '\t';
-        message++, len--)
+    for(message += 2; *message == ' ' || *message == '\t'; message++, len--)
       ;
 
     /* Find the end of the message */
-    for(; len--;)
+    while(len--)
       if(message[len] != '\r' && message[len] != '\n' && message[len] != ' ' &&
          message[len] != '\t')
         break;
 
     /* Terminate the message */
-    if(++len) {
-      message[len] = '\0';
-    }
+    message[++len] = '\0';
+    Curl_bufref_set(out, message, len, NULL);
   }
   else
     /* junk input => zero length output */
-    message = &buffer[len];
+    Curl_bufref_set(out, "", 0, NULL);
 
-  *outptr = message;
+  return CURLE_OK;
 }
 
 /***********************************************************************
@@ -437,7 +439,7 @@ static CURLcode imap_perform_capability(struct Curl_easy *data,
   imapc->tls_supported = FALSE;           /* Clear the TLS capability */
 
   /* Send the CAPABILITY command */
-  result = imap_sendf(data, conn, "CAPABILITY");
+  result = imap_sendf(data, "CAPABILITY");
 
   if(!result)
     state(data, IMAP_CAPABILITY);
@@ -451,11 +453,10 @@ static CURLcode imap_perform_capability(struct Curl_easy *data,
  *
  * Sends the STARTTLS command to start the upgrade to TLS.
  */
-static CURLcode imap_perform_starttls(struct Curl_easy *data,
-                                      struct connectdata *conn)
+static CURLcode imap_perform_starttls(struct Curl_easy *data)
 {
   /* Send the STARTTLS command */
-  CURLcode result = imap_sendf(data, conn, "STARTTLS");
+  CURLcode result = imap_sendf(data, "STARTTLS");
 
   if(!result)
     state(data, IMAP_STARTTLS);
@@ -516,7 +517,7 @@ static CURLcode imap_perform_login(struct Curl_easy *data,
   passwd = imap_atom(conn->passwd, false);
 
   /* Send the LOGIN command */
-  result = imap_sendf(data, conn, "LOGIN %s %s", user ? user : "",
+  result = imap_sendf(data, "LOGIN %s %s", user ? user : "",
                       passwd ? passwd : "");
 
   free(user);
@@ -536,20 +537,19 @@ static CURLcode imap_perform_login(struct Curl_easy *data,
  * SASL authentication mechanism.
  */
 static CURLcode imap_perform_authenticate(struct Curl_easy *data,
-                                          struct connectdata *conn,
                                           const char *mech,
-                                          const char *initresp)
+                                          const struct bufref *initresp)
 {
   CURLcode result = CURLE_OK;
-  (void)data;
+  const char *ir = (const char *) Curl_bufref_ptr(initresp);
 
-  if(initresp) {
+  if(ir) {
     /* Send the AUTHENTICATE command with the initial response */
-    result = imap_sendf(data, conn, "AUTHENTICATE %s %s", mech, initresp);
+    result = imap_sendf(data, "AUTHENTICATE %s %s", mech, ir);
   }
   else {
     /* Send the AUTHENTICATE command */
-    result = imap_sendf(data, conn, "AUTHENTICATE %s", mech);
+    result = imap_sendf(data, "AUTHENTICATE %s", mech);
   }
 
   return result;
@@ -559,15 +559,34 @@ static CURLcode imap_perform_authenticate(struct Curl_easy *data,
  *
  * imap_continue_authenticate()
  *
- * Sends SASL continuation data or cancellation.
+ * Sends SASL continuation data.
  */
 static CURLcode imap_continue_authenticate(struct Curl_easy *data,
-                                           struct connectdata *conn,
-                                           const char *resp)
+                                           const char *mech,
+                                           const struct bufref *resp)
 {
-  struct imap_conn *imapc = &conn->proto.imapc;
+  struct imap_conn *imapc = &data->conn->proto.imapc;
+
+  (void)mech;
 
-  return Curl_pp_sendf(data, &imapc->pp, "%s", resp);
+  return Curl_pp_sendf(data, &imapc->pp,
+                       "%s", (const char *) Curl_bufref_ptr(resp));
+}
+
+/***********************************************************************
+ *
+ * imap_cancel_authenticate()
+ *
+ * Sends SASL cancellation.
+ */
+static CURLcode imap_cancel_authenticate(struct Curl_easy *data,
+                                         const char *mech)
+{
+  struct imap_conn *imapc = &data->conn->proto.imapc;
+
+  (void)mech;
+
+  return Curl_pp_sendf(data, &imapc->pp, "*");
 }
 
 /***********************************************************************
@@ -594,8 +613,7 @@ static CURLcode imap_perform_authentication(struct Curl_easy *data,
   }
 
   /* Calculate the SASL login details */
-  result = Curl_sasl_start(&imapc->sasl, data, conn,
-                           imapc->ir_supported, &progress);
+  result = Curl_sasl_start(&imapc->sasl, data, imapc->ir_supported, &progress);
 
   if(!result) {
     if(progress == SASL_INPROGRESS)
@@ -622,12 +640,11 @@ static CURLcode imap_perform_authentication(struct Curl_easy *data,
 static CURLcode imap_perform_list(struct Curl_easy *data)
 {
   CURLcode result = CURLE_OK;
-  struct connectdata *conn = data->conn;
   struct IMAP *imap = data->req.p.imap;
 
   if(imap->custom)
     /* Send the custom request */
-    result = imap_sendf(data, conn, "%s%s", imap->custom,
+    result = imap_sendf(data, "%s%s", imap->custom,
                         imap->custom_params ? imap->custom_params : "");
   else {
     /* Make sure the mailbox is in the correct atom format if necessary */
@@ -637,7 +654,7 @@ static CURLcode imap_perform_list(struct Curl_easy *data)
       return CURLE_OUT_OF_MEMORY;
 
     /* Send the LIST command */
-    result = imap_sendf(data, conn, "LIST \"%s\" *", mailbox);
+    result = imap_sendf(data, "LIST \"%s\" *", mailbox);
 
     free(mailbox);
   }
@@ -678,7 +695,7 @@ static CURLcode imap_perform_select(struct Curl_easy *data)
     return CURLE_OUT_OF_MEMORY;
 
   /* Send the SELECT command */
-  result = imap_sendf(data, conn, "SELECT %s", mailbox);
+  result = imap_sendf(data, "SELECT %s", mailbox);
 
   free(mailbox);
 
@@ -694,8 +711,7 @@ static CURLcode imap_perform_select(struct Curl_easy *data)
  *
  * Sends a FETCH command to initiate the download of a message.
  */
-static CURLcode imap_perform_fetch(struct Curl_easy *data,
-                                   struct connectdata *conn)
+static CURLcode imap_perform_fetch(struct Curl_easy *data)
 {
   CURLcode result = CURLE_OK;
   struct IMAP *imap = data->req.p.imap;
@@ -704,21 +720,21 @@ static CURLcode imap_perform_fetch(struct Curl_easy *data,
 
     /* Send the FETCH command */
     if(imap->partial)
-      result = imap_sendf(data, conn, "UID FETCH %s BODY[%s]<%s>",
+      result = imap_sendf(data, "UID FETCH %s BODY[%s]<%s>",
                           imap->uid, imap->section ? imap->section : "",
                           imap->partial);
     else
-      result = imap_sendf(data, conn, "UID FETCH %s BODY[%s]",
+      result = imap_sendf(data, "UID FETCH %s BODY[%s]",
                           imap->uid, imap->section ? imap->section : "");
   }
   else if(imap->mindex) {
     /* Send the FETCH command */
     if(imap->partial)
-      result = imap_sendf(data, conn, "FETCH %s BODY[%s]<%s>",
+      result = imap_sendf(data, "FETCH %s BODY[%s]<%s>",
                           imap->mindex, imap->section ? imap->section : "",
                           imap->partial);
     else
-      result = imap_sendf(data, conn, "FETCH %s BODY[%s]",
+      result = imap_sendf(data, "FETCH %s BODY[%s]",
                           imap->mindex, imap->section ? imap->section : "");
   }
   else {
@@ -740,7 +756,6 @@ static CURLcode imap_perform_fetch(struct Curl_easy *data,
 static CURLcode imap_perform_append(struct Curl_easy *data)
 {
   CURLcode result = CURLE_OK;
-  struct connectdata *conn = data->conn;
   struct IMAP *imap = data->req.p.imap;
   char *mailbox;
 
@@ -791,7 +806,7 @@ static CURLcode imap_perform_append(struct Curl_easy *data)
     return CURLE_OUT_OF_MEMORY;
 
   /* Send the APPEND command */
-  result = imap_sendf(data, conn,
+  result = imap_sendf(data,
                       "APPEND %s (\\Seen) {%" CURL_FORMAT_CURL_OFF_T "}",
                       mailbox, data->state.infilesize);
 
@@ -809,8 +824,7 @@ static CURLcode imap_perform_append(struct Curl_easy *data)
  *
  * Sends a SEARCH command.
  */
-static CURLcode imap_perform_search(struct Curl_easy *data,
-                                    struct connectdata *conn)
+static CURLcode imap_perform_search(struct Curl_easy *data)
 {
   CURLcode result = CURLE_OK;
   struct IMAP *imap = data->req.p.imap;
@@ -822,7 +836,7 @@ static CURLcode imap_perform_search(struct Curl_easy *data,
   }
 
   /* Send the SEARCH command */
-  result = imap_sendf(data, conn, "SEARCH %s", imap->query);
+  result = imap_sendf(data, "SEARCH %s", imap->query);
 
   if(!result)
     state(data, IMAP_SEARCH);
@@ -836,11 +850,10 @@ static CURLcode imap_perform_search(struct Curl_easy *data,
  *
  * Performs the logout action prior to sclose() being called.
  */
-static CURLcode imap_perform_logout(struct Curl_easy *data,
-                                    struct connectdata *conn)
+static CURLcode imap_perform_logout(struct Curl_easy *data)
 {
   /* Send the LOGOUT command */
-  CURLcode result = imap_sendf(data, conn, "LOGOUT");
+  CURLcode result = imap_sendf(data, "LOGOUT");
 
   if(!result)
     state(data, IMAP_LOGOUT);
@@ -938,7 +951,7 @@ static CURLcode imap_state_capability_resp(struct Curl_easy *data,
     /* PREAUTH is not compatible with STARTTLS. */
     if(imapcode == IMAP_RESP_OK && imapc->tls_supported && !imapc->preauth) {
       /* Switch to TLS connection now */
-      result = imap_perform_starttls(data, conn);
+      result = imap_perform_starttls(data);
     }
     else if(data->set.use_ssl <= CURLUSESSL_TRY)
       result = imap_perform_authentication(data, conn);
@@ -993,7 +1006,7 @@ static CURLcode imap_state_auth_resp(struct Curl_easy *data,
 
   (void)instate; /* no use for this yet */
 
-  result = Curl_sasl_continue(&imapc->sasl, data, conn, imapcode, &progress);
+  result = Curl_sasl_continue(&imapc->sasl, data, imapcode, &progress);
   if(!result)
     switch(progress) {
     case SASL_DONE:
@@ -1094,9 +1107,9 @@ static CURLcode imap_state_select_resp(struct Curl_easy *data, int imapcode,
       if(imap->custom)
         result = imap_perform_list(data);
       else if(imap->query)
-        result = imap_perform_search(data, conn);
+        result = imap_perform_search(data);
       else
-        result = imap_perform_fetch(data, conn);
+        result = imap_perform_fetch(data);
     }
   }
   else {
@@ -1441,7 +1454,7 @@ static CURLcode imap_connect(struct Curl_easy *data, bool *done)
 
   /* Set the default preferred authentication type and mechanism */
   imapc->preftype = IMAP_TYPE_ANY;
-  Curl_sasl_init(&imapc->sasl, &saslimap);
+  Curl_sasl_init(&imapc->sasl, data, &saslimap);
 
   Curl_dyn_init(&imapc->dyn, DYN_IMAP_CMD);
   /* Initialise the pingpong layer */
@@ -1568,10 +1581,10 @@ static CURLcode imap_perform(struct Curl_easy *data, bool *connected,
     result = imap_perform_list(data);
   else if(!imap->custom && selected && (imap->uid || imap->mindex))
     /* FETCH from the same mailbox */
-    result = imap_perform_fetch(data, conn);
+    result = imap_perform_fetch(data);
   else if(!imap->custom && selected && imap->query)
     /* SEARCH the current mailbox */
-    result = imap_perform_search(data, conn);
+    result = imap_perform_search(data);
   else if(imap->mailbox && !selected &&
          (imap->custom || imap->uid || imap->mindex || imap->query))
     /* SELECT the mailbox */
@@ -1643,7 +1656,7 @@ static CURLcode imap_disconnect(struct Curl_easy *data,
   /* The IMAP session may or may not have been allocated/setup at this
      point! */
   if(!dead_connection && conn->bits.protoconnstart) {
-    if(!imap_perform_logout(data, conn))
+    if(!imap_perform_logout(data))
       (void)imap_block_statemach(data, conn, TRUE); /* ignore errors */
   }
 
@@ -1747,17 +1760,16 @@ static CURLcode imap_setup_connection(struct Curl_easy *data,
  *
  * Designed to never block.
  */
-static CURLcode imap_sendf(struct Curl_easy *data,
-                           struct connectdata *conn, const char *fmt, ...)
+static CURLcode imap_sendf(struct Curl_easy *data, const char *fmt, ...)
 {
   CURLcode result = CURLE_OK;
-  struct imap_conn *imapc = &conn->proto.imapc;
+  struct imap_conn *imapc = &data->conn->proto.imapc;
 
   DEBUGASSERT(fmt);
 
   /* Calculate the tag based on the connection ID and command ID */
   msnprintf(imapc->resptag, sizeof(imapc->resptag), "%c%03d",
-            'A' + curlx_sltosi(conn->connection_id % 26),
+            'A' + curlx_sltosi(data->conn->connection_id % 26),
             (++imapc->cmdid)%1000);
 
   /* start with a blank buffer */
@@ -1911,8 +1923,6 @@ static CURLcode imap_parse_url_options(struct connectdata *conn)
   struct imap_conn *imapc = &conn->proto.imapc;
   const char *ptr = conn->options;
 
-  imapc->sasl.resetprefs = TRUE;
-
   while(!result && ptr && *ptr) {
     const char *key = ptr;
     const char *value;