curl 7.38.0 (reduced)

Extract upstream curl using the following shell code.

url=git://github.com/bagder/curl.git &&
v=7.38.0 &&
r=202aa9f7 &&
paths="
  CMake/*
  CMakeLists.txt
  COPYING
  include/curl/*.h
  include/curl/curlbuild.h.cmake
  lib/*.c
  lib/*.h
  lib/CMakeLists.txt
  lib/Makefile.inc
  lib/curl_config.h.cmake
  lib/libcurl.rc
  lib/vtls/*.c
  lib/vtls/*.h
" &&
mkdir curl-$v-g$r-reduced &&
git clone $url curl-git &&
date=$(cd curl-git && git log -n 1 --format='%cd' $r) &&
(cd curl-git && git checkout $r &&
 git archive --format=tar $r -- $paths) |
(cd curl-$v-g$r-reduced && tar xv &&
 rm lib/config-*.h) &&
echo "g$r date: $date"

1 files changed, 404 insertions, 296 deletions

diff --git a/lib/security.c b/lib/security.c
index 4c9aed8..508c7b4 100644
--- a/lib/security.c
+++ b/lib/security.c
@@ -7,8 +7,11 @@
  * rewrite to work around the paragraph 2 in the BSD licenses as explained
  * below.
  *
- * Copyright (c) 1998, 1999 Kungliga Tekniska Högskolan
+ * Copyright (c) 1998, 1999, 2013 Kungliga Tekniska Högskolan
  * (Royal Institute of Technology, Stockholm, Sweden).
+ *
+ * Copyright (C) 2001 - 2013, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -38,42 +41,39 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.  */
 
-#include "setup.h"
+#include "curl_setup.h"
 
 #ifndef CURL_DISABLE_FTP
-#ifdef HAVE_KRB4
+#ifdef HAVE_GSSAPI
 
-#define _MPRINTF_REPLACE /* we want curl-functions instead of native ones */
-#include <curl/mprintf.h>
-
-#include <stdlib.h>
-#include <string.h>
+#ifdef HAVE_NETDB_H
 #include <netdb.h>
+#endif
 
-#ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#ifdef HAVE_LIMITS_H
+#include <limits.h>
 #endif
 
 #include "urldata.h"
-#include "krb4.h"
-#include "base64.h"
-#include "sendf.h"
+#include "curl_base64.h"
+#include "curl_memory.h"
+#include "curl_sec.h"
 #include "ftp.h"
-#include "memory.h"
+#include "sendf.h"
+#include "rawstr.h"
+#include "warnless.h"
 
 /* The last #include file should be: */
 #include "memdebug.h"
 
-#define min(a, b)   ((a) < (b) ? (a) : (b))
-
 static const struct {
-    enum protection_level level;
-    const char *name;
+  enum protection_level level;
+  const char *name;
 } level_names[] = {
-    { prot_clear, "clear" },
-    { prot_safe, "safe" },
-    { prot_confidential, "confidential" },
-    { prot_private, "private" }
+  { PROT_CLEAR, "clear" },
+  { PROT_SAFE, "safe" },
+  { PROT_CONFIDENTIAL, "confidential" },
+  { PROT_PRIVATE, "private" }
 };
 
 static enum protection_level
@@ -81,196 +81,270 @@ name_to_level(const char *name)
 {
   int i;
   for(i = 0; i < (int)sizeof(level_names)/(int)sizeof(level_names[0]); i++)
-    if(curl_strnequal(level_names[i].name, name, strlen(name)))
+    if(checkprefix(name, level_names[i].name))
       return level_names[i].level;
-  return (enum protection_level)-1;
+  return PROT_NONE;
+}
+
+/* Convert a protocol |level| to its char representation.
+   We take an int to catch programming mistakes. */
+static char level_to_char(int level) {
+  switch(level) {
+  case PROT_CLEAR:
+    return 'C';
+  case PROT_SAFE:
+    return 'S';
+  case PROT_CONFIDENTIAL:
+    return 'E';
+  case PROT_PRIVATE:
+    return 'P';
+  case PROT_CMD:
+    /* Fall through */
+  default:
+    /* Those 2 cases should not be reached! */
+    break;
+  }
+  DEBUGASSERT(0);
+  /* Default to the most secure alternative. */
+  return 'P';
 }
 
 static const struct Curl_sec_client_mech * const mechs[] = {
-#ifdef KRB5
-  /* not supported */
+#ifdef HAVE_GSSAPI
+  &Curl_krb5_client_mech,
 #endif
-#ifdef HAVE_KRB4
-    &Curl_krb4_client_mech,
-#endif
-    NULL
+  NULL
 };
 
-int
-Curl_sec_getc(struct connectdata *conn, FILE *F)
+/* Send an FTP command defined by |message| and the optional arguments. The
+   function returns the ftp_code. If an error occurs, -1 is returned. */
+static int ftp_send_command(struct connectdata *conn, const char *message, ...)
 {
-  if(conn->sec_complete && conn->data_prot) {
-    char c;
-    if(Curl_sec_read(conn, fileno(F), &c, 1) <= 0)
-      return EOF;
-    return c;
+  int ftp_code;
+  ssize_t nread;
+  va_list args;
+  char print_buffer[50];
+
+  va_start(args, message);
+  vsnprintf(print_buffer, sizeof(print_buffer), message, args);
+  va_end(args);
+
+  if(Curl_ftpsendf(conn, print_buffer) != CURLE_OK) {
+    ftp_code = -1;
   }
-  else
-    return getc(F);
+  else {
+    if(Curl_GetFTPResponse(&nread, conn, &ftp_code) != CURLE_OK)
+      ftp_code = -1;
+  }
+
+  (void)nread; /* Unused */
+  return ftp_code;
 }
 
-static int
-block_read(int fd, void *buf, size_t len)
+/* Read |len| from the socket |fd| and store it in |to|. Return a CURLcode
+   saying whether an error occurred or CURLE_OK if |len| was read. */
+static CURLcode
+socket_read(curl_socket_t fd, void *to, size_t len)
 {
-  unsigned char *p = buf;
-  int b;
-  while(len) {
-    b = read(fd, p, len);
-    if (b == 0)
-      return 0;
-    else if (b < 0)
-      return -1;
-    len -= b;
-    p += b;
+  char *to_p = to;
+  CURLcode code;
+  ssize_t nread;
+
+  while(len > 0) {
+    code = Curl_read_plain(fd, to_p, len, &nread);
+    if(code == CURLE_OK) {
+      len -= nread;
+      to_p += nread;
+    }
+    else {
+      /* FIXME: We are doing a busy wait */
+      if(code == CURLE_AGAIN)
+        continue;
+      return code;
+    }
   }
-  return p - (unsigned char*)buf;
+  return CURLE_OK;
 }
 
-static int
-block_write(int fd, void *buf, size_t len)
+
+/* Write |len| bytes from the buffer |to| to the socket |fd|. Return a
+   CURLcode saying whether an error occurred or CURLE_OK if |len| was
+   written. */
+static CURLcode
+socket_write(struct connectdata *conn, curl_socket_t fd, const void *to,
+             size_t len)
 {
-  unsigned char *p = buf;
-  int b;
-  while(len) {
-    b = write(fd, p, len);
-    if(b < 0)
-      return -1;
-    len -= b;
-    p += b;
+  const char *to_p = to;
+  CURLcode code;
+  ssize_t written;
+
+  while(len > 0) {
+    code = Curl_write_plain(conn, fd, to_p, len, &written);
+    if(code == CURLE_OK) {
+      len -= written;
+      to_p += written;
+    }
+    else {
+      /* FIXME: We are doing a busy wait */
+      if(code == CURLE_AGAIN)
+        continue;
+      return code;
+    }
   }
-  return p - (unsigned char*)buf;
+  return CURLE_OK;
 }
 
-static int
-sec_get_data(struct connectdata *conn,
-             int fd, struct krb4buffer *buf)
+static CURLcode read_data(struct connectdata *conn,
+                          curl_socket_t fd,
+                          struct krb5buffer *buf)
 {
   int len;
-  int b;
+  void* tmp;
+  CURLcode ret;
+
+  ret = socket_read(fd, &len, sizeof(len));
+  if(ret != CURLE_OK)
+    return ret;
 
-  b = block_read(fd, &len, sizeof(len));
-  if (b == 0)
-    return 0;
-  else if (b < 0)
-    return -1;
   len = ntohl(len);
-  buf->data = realloc(buf->data, len);
-  b = block_read(fd, buf->data, len);
-  if (b == 0)
-    return 0;
-  else if (b < 0)
-    return -1;
-  buf->size = (conn->mech->decode)(conn->app_data, buf->data, len,
-                                   conn->data_prot, conn);
+  tmp = realloc(buf->data, len);
+  if(tmp == NULL)
+    return CURLE_OUT_OF_MEMORY;
+
+  buf->data = tmp;
+  ret = socket_read(fd, buf->data, len);
+  if(ret != CURLE_OK)
+    return ret;
+  buf->size = conn->mech->decode(conn->app_data, buf->data, len,
+                                 conn->data_prot, conn);
   buf->index = 0;
-  return 0;
+  return CURLE_OK;
 }
 
 static size_t
-buffer_read(struct krb4buffer *buf, void *data, size_t len)
+buffer_read(struct krb5buffer *buf, void *data, size_t len)
 {
-    len = min(len, buf->size - buf->index);
-    memcpy(data, (char*)buf->data + buf->index, len);
-    buf->index += len;
-    return len;
+  if(buf->size - buf->index < len)
+    len = buf->size - buf->index;
+  memcpy(data, (char*)buf->data + buf->index, len);
+  buf->index += len;
+  return len;
 }
 
-static size_t
-buffer_write(struct krb4buffer *buf, void *data, size_t len)
+/* Matches Curl_recv signature */
+static ssize_t sec_recv(struct connectdata *conn, int sockindex,
+                        char *buffer, size_t len, CURLcode *err)
 {
-    if(buf->index + len > buf->size) {
-        void *tmp;
-        if(buf->data == NULL)
-            tmp = malloc(1024);
-        else
-            tmp = realloc(buf->data, buf->index + len);
-        if(tmp == NULL)
-            return -1;
-        buf->data = tmp;
-        buf->size = buf->index + len;
-    }
-    memcpy((char*)buf->data + buf->index, data, len);
-    buf->index += len;
-    return len;
-}
+  size_t bytes_read;
+  size_t total_read = 0;
+  curl_socket_t fd = conn->sock[sockindex];
 
-int
-Curl_sec_read(struct connectdata *conn, int fd, void *buffer, int length)
-{
-    size_t len;
-    int rx = 0;
+  *err = CURLE_OK;
 
-    if(conn->sec_complete == 0 || conn->data_prot == 0)
-      return read(fd, buffer, length);
+  /* Handle clear text response. */
+  if(conn->sec_complete == 0 || conn->data_prot == PROT_CLEAR)
+      return read(fd, buffer, len);
 
-    if(conn->in_buffer.eof_flag){
-      conn->in_buffer.eof_flag = 0;
-      return 0;
-    }
+  if(conn->in_buffer.eof_flag) {
+    conn->in_buffer.eof_flag = 0;
+    return 0;
+  }
 
-    len = buffer_read(&conn->in_buffer, buffer, length);
-    length -= len;
-    rx += len;
-    buffer = (char*)buffer + len;
-
-    while(length) {
-      if(sec_get_data(conn, fd, &conn->in_buffer) < 0)
-        return -1;
-      if(conn->in_buffer.size == 0) {
-        if(rx)
-          conn->in_buffer.eof_flag = 1;
-        return rx;
-      }
-      len = buffer_read(&conn->in_buffer, buffer, length);
-      length -= len;
-      rx += len;
-      buffer = (char*)buffer + len;
-    }
-    return rx;
-}
+  bytes_read = buffer_read(&conn->in_buffer, buffer, len);
+  len -= bytes_read;
+  total_read += bytes_read;
+  buffer += bytes_read;
 
-static int
-sec_send(struct connectdata *conn, int fd, char *from, int length)
-{
-  int bytes;
-  void *buf;
-  bytes = (conn->mech->encode)(conn->app_data, from, length, conn->data_prot,
-                               &buf, conn);
-  bytes = htonl(bytes);
-  block_write(fd, &bytes, sizeof(bytes));
-  block_write(fd, buf, ntohl(bytes));
-  free(buf);
-  return length;
+  while(len > 0) {
+    if(read_data(conn, fd, &conn->in_buffer) != CURLE_OK)
+      return -1;
+    if(conn->in_buffer.size == 0) {
+      if(bytes_read > 0)
+        conn->in_buffer.eof_flag = 1;
+      return bytes_read;
+    }
+    bytes_read = buffer_read(&conn->in_buffer, buffer, len);
+    len -= bytes_read;
+    total_read += bytes_read;
+    buffer += bytes_read;
+  }
+  /* FIXME: Check for overflow */
+  return total_read;
 }
 
-int
-Curl_sec_fflush_fd(struct connectdata *conn, int fd)
+/* Send |length| bytes from |from| to the |fd| socket taking care of encoding
+   and negociating with the server. |from| can be NULL. */
+/* FIXME: We don't check for errors nor report any! */
+static void do_sec_send(struct connectdata *conn, curl_socket_t fd,
+                        const char *from, int length)
 {
-  if(conn->data_prot != prot_clear) {
-    if(conn->out_buffer.index > 0){
-      Curl_sec_write(conn, fd,
-                conn->out_buffer.data, conn->out_buffer.index);
-      conn->out_buffer.index = 0;
+  int bytes, htonl_bytes; /* 32-bit integers for htonl */
+  char *buffer = NULL;
+  char *cmd_buffer;
+  size_t cmd_size = 0;
+  CURLcode error;
+  enum protection_level prot_level = conn->data_prot;
+  bool iscmd = (prot_level == PROT_CMD)?TRUE:FALSE;
+
+  DEBUGASSERT(prot_level > PROT_NONE && prot_level < PROT_LAST);
+
+  if(iscmd) {
+    if(!strncmp(from, "PASS ", 5) || !strncmp(from, "ACCT ", 5))
+      prot_level = PROT_PRIVATE;
+    else
+      prot_level = conn->command_prot;
+  }
+  bytes = conn->mech->encode(conn->app_data, from, length, prot_level,
+                             (void**)&buffer, conn);
+  if(!buffer || bytes <= 0)
+    return; /* error */
+
+  if(iscmd) {
+    error = Curl_base64_encode(conn->data, buffer, curlx_sitouz(bytes),
+                               &cmd_buffer, &cmd_size);
+    if(error) {
+      free(buffer);
+      return; /* error */
+    }
+    if(cmd_size > 0) {
+      static const char *enc = "ENC ";
+      static const char *mic = "MIC ";
+      if(prot_level == PROT_PRIVATE)
+        socket_write(conn, fd, enc, 4);
+      else
+        socket_write(conn, fd, mic, 4);
+
+      socket_write(conn, fd, cmd_buffer, cmd_size);
+      socket_write(conn, fd, "\r\n", 2);
+      infof(conn->data, "Send: %s%s\n", prot_level == PROT_PRIVATE?enc:mic,
+            cmd_buffer);
+      free(cmd_buffer);
     }
-    sec_send(conn, fd, NULL, 0);
   }
-  return 0;
+  else {
+    htonl_bytes = htonl(bytes);
+    socket_write(conn, fd, &htonl_bytes, sizeof(htonl_bytes));
+    socket_write(conn, fd, buffer, curlx_sitouz(bytes));
+  }
+  free(buffer);
 }
 
-int
-Curl_sec_write(struct connectdata *conn, int fd, char *buffer, int length)
+static ssize_t sec_write(struct connectdata *conn, curl_socket_t fd,
+                         const char *buffer, size_t length)
 {
-  int len = conn->buffer_size;
-  int tx = 0;
-
-  if(conn->data_prot == prot_clear)
-    return write(fd, buffer, length);
-
-  len -= (conn->mech->overhead)(conn->app_data, conn->data_prot, len);
-  while(length){
-    if(length < len)
+  /* FIXME: Check for overflow */
+  ssize_t tx = 0, len = conn->buffer_size;
+
+  len -= conn->mech->overhead(conn->app_data, conn->data_prot,
+                              curlx_sztosi(len));
+  if(len <= 0)
+    len = length;
+  while(length) {
+    if(len >= 0 || length < (size_t)len) {
+      /* FIXME: Check for overflow. */
       len = length;
-    sec_send(conn, fd, buffer, len);
+    }
+    do_sec_send(conn, fd, buffer, curlx_sztosi(len));
     length -= len;
     buffer += len;
     tx += len;
@@ -278,216 +352,250 @@ Curl_sec_write(struct connectdata *conn, int fd, char *buffer, int length)
   return tx;
 }
 
-ssize_t
-Curl_sec_send(struct connectdata *conn, int num, char *buffer, int length)
-{
-  curl_socket_t fd = conn->sock[num];
-  return (ssize_t)Curl_sec_write(conn, fd, buffer, length);
-}
-
-int
-Curl_sec_putc(struct connectdata *conn, int c, FILE *F)
+/* Matches Curl_send signature */
+static ssize_t sec_send(struct connectdata *conn, int sockindex,
+                        const void *buffer, size_t len, CURLcode *err)
 {
-  char ch = c;
-  if(conn->data_prot == prot_clear)
-    return putc(c, F);
-
-  buffer_write(&conn->out_buffer, &ch, 1);
-  if(c == '\n' || conn->out_buffer.index >= 1024 /* XXX */) {
-    Curl_sec_write(conn, fileno(F), conn->out_buffer.data,
-                   conn->out_buffer.index);
-    conn->out_buffer.index = 0;
-  }
-  return c;
+  curl_socket_t fd = conn->sock[sockindex];
+  *err = CURLE_OK;
+  return sec_write(conn, fd, buffer, len);
 }
 
-int
-Curl_sec_read_msg(struct connectdata *conn, char *s, int level)
+int Curl_sec_read_msg(struct connectdata *conn, char *buffer,
+                      enum protection_level level)
 {
-  int len;
-  unsigned char *buf;
-  int code;
+  /* decoded_len should be size_t or ssize_t but conn->mech->decode returns an
+     int */
+  int decoded_len;
+  char *buf;
+  int ret_code;
+  size_t decoded_sz = 0;
+  CURLcode error;
+
+  DEBUGASSERT(level > PROT_NONE && level < PROT_LAST);
+
+  error = Curl_base64_decode(buffer + 4, (unsigned char **)&buf, &decoded_sz);
+  if(error || decoded_sz == 0)
+    return -1;
 
-  len = Curl_base64_decode(s + 4, &buf); /* XXX */
-  if(len > 0)
-    len = (conn->mech->decode)(conn->app_data, buf, len, level, conn);
-  else
+  if(decoded_sz > (size_t)INT_MAX) {
+    free(buf);
     return -1;
+  }
+  decoded_len = curlx_uztosi(decoded_sz);
 
-  if(len < 0) {
+  decoded_len = conn->mech->decode(conn->app_data, buf, decoded_len,
+                                   level, conn);
+  if(decoded_len <= 0) {
     free(buf);
     return -1;
   }
 
-  buf[len] = '\0';
+  if(conn->data->set.verbose) {
+    buf[decoded_len] = '\n';
+    Curl_debug(conn->data, CURLINFO_HEADER_IN, buf, decoded_len + 1, conn);
+  }
 
+  buf[decoded_len] = '\0';
+  DEBUGASSERT(decoded_len > 3);
   if(buf[3] == '-')
-    code = 0;
-  else
-    sscanf((char *)buf, "%d", &code);
-  if(buf[len-1] == '\n')
-    buf[len-1] = '\0';
-  strcpy(s, (char *)buf);
+    ret_code = 0;
+  else {
+    /* Check for error? */
+    sscanf(buf, "%d", &ret_code);
+  }
+
+  if(buf[decoded_len - 1] == '\n')
+    buf[decoded_len - 1] = '\0';
+  /* FIXME: Is |buffer| length always greater than |decoded_len|? */
+  strcpy(buffer, buf);
   free(buf);
-  return code;
+  return ret_code;
 }
 
-enum protection_level
-Curl_set_command_prot(struct connectdata *conn, enum protection_level level)
+/* FIXME: The error code returned here is never checked. */
+static int sec_set_protection_level(struct connectdata *conn)
 {
-  enum protection_level old = conn->command_prot;
-  conn->command_prot = level;
-  return old;
-}
+  int code;
+  char* pbsz;
+  static unsigned int buffer_size = 1 << 20; /* 1048576 */
+  enum protection_level level = conn->request_data_prot;
 
-static int
-sec_prot_internal(struct connectdata *conn, int level)
-{
-  char *p;
-  unsigned int s = 1048576;
-  ssize_t nread;
+  DEBUGASSERT(level > PROT_NONE && level < PROT_LAST);
 
-  if(!conn->sec_complete){
-    infof(conn->data, "No security data exchange has taken place.\n");
+  if(!conn->sec_complete) {
+    infof(conn->data, "Trying to change the protection level after the"
+                      "completion of the data exchange.\n");
     return -1;
   }
 
-  if(level){
-    int code;
-    if(Curl_ftpsendf(conn, "PBSZ %u", s))
-      return -1;
+  /* Bail out if we try to set up the same level */
+  if(conn->data_prot == level)
+    return 0;
 
-    if(Curl_GetFTPResponse(&nread, conn, &code))
+  if(level) {
+    code = ftp_send_command(conn, "PBSZ %u", buffer_size);
+    if(code < 0)
       return -1;
 
-    if(code/100 != '2'){
-      failf(conn->data, "Failed to set protection buffer size.");
+    if(code/100 != 2) {
+      failf(conn->data, "Failed to set the protection's buffer size.");
       return -1;
     }
-    conn->buffer_size = s;
-
-    p = strstr(conn->data->state.buffer, "PBSZ=");
-    if(p)
-      sscanf(p, "PBSZ=%u", &s);
-    if(s < conn->buffer_size)
-      conn->buffer_size = s;
+    conn->buffer_size = buffer_size;
+
+    pbsz = strstr(conn->data->state.buffer, "PBSZ=");
+    if(pbsz) {
+      /* FIXME: Checks for errors in sscanf? */
+      sscanf(pbsz, "PBSZ=%u", &buffer_size);
+      if(buffer_size < conn->buffer_size)
+        conn->buffer_size = buffer_size;
+    }
   }
 
-  if(Curl_ftpsendf(conn, "PROT %c", level["CSEP"]))
-    return -1;
+  /* Now try to negiociate the protection level. */
+  code = ftp_send_command(conn, "PROT %c", level_to_char(level));
 
-  if(Curl_GetFTPResponse(&nread, conn, NULL))
+  if(code < 0)
     return -1;
 
-  if(conn->data->state.buffer[0] != '2'){
-    failf(conn->data, "Failed to set protection level.");
+  if(code/100 != 2) {
+    failf(conn->data, "Failed to set the protection level.");
     return -1;
   }
 
-  conn->data_prot = (enum protection_level)level;
-  return 0;
-}
+  conn->data_prot = level;
+  if(level == PROT_PRIVATE)
+    conn->command_prot = level;
 
-void
-Curl_sec_set_protection_level(struct connectdata *conn)
-{
-  if(conn->sec_complete && conn->data_prot != conn->request_data_prot)
-    sec_prot_internal(conn, conn->request_data_prot);
+  return 0;
 }
 
-
 int
 Curl_sec_request_prot(struct connectdata *conn, const char *level)
 {
-  int l = name_to_level(level);
-  if(l == -1)
+  enum protection_level l = name_to_level(level);
+  if(l == PROT_NONE)
     return -1;
-  conn->request_data_prot = (enum protection_level)l;
+  DEBUGASSERT(l > PROT_NONE && l < PROT_LAST);
+  conn->request_data_prot = l;
   return 0;
 }
 
-int
-Curl_sec_login(struct connectdata *conn)
+static CURLcode choose_mech(struct connectdata *conn)
 {
   int ret;
-  const struct Curl_sec_client_mech * const *m;
-  ssize_t nread;
-  struct SessionHandle *data=conn->data;
-  int ftpcode;
-
-  for(m = mechs; *m && (*m)->name; m++) {
-    void *tmp;
-
-    tmp = realloc(conn->app_data, (*m)->size);
-    if (tmp == NULL) {
-      failf (data, "realloc %u failed", (*m)->size);
-      return -1;
-    }
-    conn->app_data = tmp;
-
-    if((*m)->init && (*(*m)->init)(conn->app_data) != 0) {
-      infof(data, "Skipping %s...\n", (*m)->name);
+  struct SessionHandle *data = conn->data;
+  const struct Curl_sec_client_mech * const *mech;
+  void *tmp_allocation;
+  const char *mech_name;
+
+  for(mech = mechs; (*mech); ++mech) {
+    mech_name = (*mech)->name;
+    /* We have no mechanism with a NULL name but keep this check */
+    DEBUGASSERT(mech_name != NULL);
+    if(mech_name == NULL) {
+      infof(data, "Skipping mechanism with empty name (%p)\n", (void *)mech);
       continue;
     }
-    infof(data, "Trying %s...\n", (*m)->name);
+    tmp_allocation = realloc(conn->app_data, (*mech)->size);
+    if(tmp_allocation == NULL) {
+      failf(data, "Failed realloc of size %u", (*mech)->size);
+      mech = NULL;
+      return CURLE_OUT_OF_MEMORY;
+    }
+    conn->app_data = tmp_allocation;
 
-    if(Curl_ftpsendf(conn, "AUTH %s", (*m)->name))
-      return -1;
+    if((*mech)->init) {
+      ret = (*mech)->init(conn->app_data);
+      if(ret != 0) {
+        infof(data, "Failed initialization for %s. Skipping it.\n", mech_name);
+        continue;
+      }
+    }
 
-    if(Curl_GetFTPResponse(&nread, conn, &ftpcode))
-      return -1;
+    infof(data, "Trying mechanism %s...\n", mech_name);
+    ret = ftp_send_command(conn, "AUTH %s", mech_name);
+    if(ret < 0)
+      /* FIXME: This error is too generic but it is OK for now. */
+      return CURLE_COULDNT_CONNECT;
 
-    if(conn->data->state.buffer[0] != '3'){
-      switch(ftpcode) {
+    if(ret/100 != 3) {
+      switch(ret) {
       case 504:
-        infof(data,
-              "%s is not supported by the server.\n", (*m)->name);
+        infof(data, "Mechanism %s is not supported by the server (server "
+                    "returned ftp code: 504).\n", mech_name);
         break;
       case 534:
-        infof(data, "%s rejected as security mechanism.\n", (*m)->name);
+        infof(data, "Mechanism %s was rejected by the server (server returned "
+                    "ftp code: 534).\n", mech_name);
         break;
       default:
-        if(conn->data->state.buffer[0] == '5') {
-          infof(data, "The server doesn't support the FTP "
-                "security extensions.\n");
-          return -1;
+        if(ret/100 == 5) {
+          infof(data, "server does not support the security extensions\n");
+          return CURLE_USE_SSL_FAILED;
         }
         break;
       }
       continue;
     }
 
-    ret = (*(*m)->auth)(conn->app_data, conn);
+    /* Authenticate */
+    ret = (*mech)->auth(conn->app_data, conn);
 
     if(ret == AUTH_CONTINUE)
       continue;
-    else if(ret != AUTH_OK){
-      /* mechanism is supposed to output error string */
+    else if(ret != AUTH_OK) {
+      /* Mechanism has dumped the error to stderr, don't error here. */
       return -1;
     }
-    conn->mech = *m;
+    DEBUGASSERT(ret == AUTH_OK);
+
+    conn->mech = *mech;
     conn->sec_complete = 1;
-    conn->command_prot = prot_safe;
+    conn->recv[FIRSTSOCKET] = sec_recv;
+    conn->send[FIRSTSOCKET] = sec_send;
+    conn->recv[SECONDARYSOCKET] = sec_recv;
+    conn->send[SECONDARYSOCKET] = sec_send;
+    conn->command_prot = PROT_SAFE;
+    /* Set the requested protection level */
+    /* BLOCKING */
+    (void)sec_set_protection_level(conn);
     break;
   }
 
-  return *m == NULL;
+  return mech != NULL ? CURLE_OK : CURLE_FAILED_INIT;
 }
 
+CURLcode
+Curl_sec_login(struct connectdata *conn)
+{
+  return choose_mech(conn);
+}
+
+
 void
 Curl_sec_end(struct connectdata *conn)
 {
-  if (conn->mech != NULL) {
-    if(conn->mech->end)
-      (conn->mech->end)(conn->app_data);
-    memset(conn->app_data, 0, conn->mech->size);
+  if(conn->mech != NULL && conn->mech->end)
+    conn->mech->end(conn->app_data);
+  if(conn->app_data) {
     free(conn->app_data);
     conn->app_data = NULL;
   }
+  if(conn->in_buffer.data) {
+    free(conn->in_buffer.data);
+    conn->in_buffer.data = NULL;
+    conn->in_buffer.size = 0;
+    conn->in_buffer.index = 0;
+    /* FIXME: Is this really needed? */
+    conn->in_buffer.eof_flag = 0;
+  }
   conn->sec_complete = 0;
-  conn->data_prot = (enum protection_level)0;
-  conn->mech=NULL;
+  conn->data_prot = PROT_CLEAR;
+  conn->mech = NULL;
 }
 
-#endif /* HAVE_KRB4 */
+#endif /* HAVE_GSSAPI */
+
 #endif /* CURL_DISABLE_FTP */