release/src/router/vsftpd/netstr.c

   1 /*
   2  * Part of Very Secure FTPd
   3  * Licence: GPL v2
   4  * Author: Chris Evans
   5  * netstr.c
   6  *
   7  * The netstr interface extends the standard string interface, adding
   8  * functions which can cope safely with building strings from the network,
   9  * and send them out too.
  10  */
  11
  12 #include "netstr.h"
  13 #include "str.h"
  14 #include "sysstr.h"
  15 #include "utility.h"
  16 #include "sysutil.h"
  17
  18 int
  19 str_netfd_alloc(struct vsf_session* p_sess,
  20                 struct mystr* p_str,
  21                 char term,
  22                 char* p_readbuf,
  23                 unsigned int maxlen,
  24                 str_netfd_read_t p_peekfunc,
  25                 str_netfd_read_t p_readfunc)
  26 {
  27   int retval;
  28   unsigned int bytes_read;
  29   unsigned int i;
  30   char* p_readpos = p_readbuf;
  31   unsigned int left = maxlen;
  32   str_empty(p_str);
  33   while (1)
  34   {
  35     if (p_readpos + left != p_readbuf + maxlen)
  36     {
  37       bug("poor buffer accounting in str_netfd_alloc");
  38     }
  39     /* Did we hit the max? */
  40     if (left == 0)
  41     {
  42       return -1;
  43     }
  44     retval = (*p_peekfunc)(p_sess, p_readpos, left);
  45     if (vsf_sysutil_retval_is_error(retval))
  46     {
  47       die("vsf_sysutil_recv_peek");
  48     }
  49     else if (retval == 0)
  50     {
  51       return 0;
  52     }
  53     bytes_read = (unsigned int) retval;
  54     /* Search for the terminator */
  55     for (i=0; i < bytes_read; i++)
  56     {
  57       if (p_readpos[i] == term)
  58       {
  59         /* Got it! */
  60         i++;
  61         retval = (*p_readfunc)(p_sess, p_readpos, i);
  62         if (vsf_sysutil_retval_is_error(retval) ||
  63             (unsigned int) retval != i)
  64         {
  65           die("vsf_sysutil_read_loop");
  66         }
  67         if (p_readpos[i - 1] != term)
  68         {
  69           die("missing terminator in str_netfd_alloc");
  70         }
  71         str_alloc_alt_term(p_str, p_readbuf, term);
  72         return (int) i;
  73       }
  74     }
  75     /* Not found in this read chunk, so consume the data and re-loop */
  76     if (bytes_read > left)
  77     {
  78       bug("bytes_read > left in str_netfd_alloc");
  79     }
  80     left -= bytes_read;
  81     retval = (*p_readfunc)(p_sess, p_readpos, bytes_read);
  82     if (vsf_sysutil_retval_is_error(retval) ||
  83         (unsigned int) retval != bytes_read)
  84     {
  85       die("vsf_sysutil_read_loop");
  86     }
  87     p_readpos += bytes_read;
  88   } /* END: while(1) */
  89 }
  90
  91 int
  92 str_netfd_write(const struct mystr* p_str, int fd)
  93 {
  94   int ret = 0;
  95   int retval;
  96   unsigned int str_len = str_getlen(p_str);
  97   if (str_len == 0)
  98   {
  99     bug("zero str_len in str_netfd_write");
 100   }
 101   retval = str_write_loop(p_str, fd);
 102   if (vsf_sysutil_retval_is_error(retval) || (unsigned int) retval != str_len)
 103   {
 104     ret = -1;
 105   }
 106   return ret;
 107 }
 108
 109 int
 110 str_netfd_read(struct mystr* p_str, int fd, unsigned int len)
 111 {
 112   int retval;
 113   str_reserve(p_str, len);
 114   str_trunc(p_str, len);
 115   retval = str_read_loop(p_str, fd);
 116   if (vsf_sysutil_retval_is_error(retval) || (unsigned int) retval != len)
 117   {
 118     return -1;
 119   }
 120   return retval;
 121 }
 122