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   while (1)
  33   {
  34     if (p_readpos + left != p_readbuf + maxlen)
  35     {
  36       bug("poor buffer accounting in str_netfd_alloc");
  37     }
  38     /* Did we hit the max? */
  39     if (left == 0)
  40     {
  41       str_empty(p_str);
  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       die("vsf_sysutil_recv_peek: no data");
  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         retval = (*p_readfunc)(p_sess, p_readpos, i + 1);
  61         if (vsf_sysutil_retval_is_error(retval) ||
  62             (unsigned int) retval != i + 1)
  63         {
  64           die("vsf_sysutil_read_loop");
  65         }
  66         if (p_readpos[i] != term)
  67         {
  68           die("missing terminator in str_netfd_alloc");
  69         }
  70         str_alloc_alt_term(p_str, p_readbuf, term);
  71         return (int) i;
  72       }
  73     }
  74     /* Not found in this read chunk, so consume the data and re-loop */
  75     if (bytes_read > left)
  76     {
  77       bug("bytes_read > left in str_netfd_alloc");
  78     }
  79     left -= bytes_read;
  80     retval = (*p_readfunc)(p_sess, p_readpos, bytes_read);
  81     if (vsf_sysutil_retval_is_error(retval) ||
  82         (unsigned int) retval != bytes_read)
  83     {
  84       die("vsf_sysutil_read_loop");
  85     }
  86     p_readpos += bytes_read;
  87   } /* END: while(1) */
  88 }
  89
  90 int
  91 str_netfd_write(const struct mystr* p_str, int fd)
  92 {
  93   int ret = 0;
  94   int retval;
  95   unsigned int str_len = str_getlen(p_str);
  96   if (str_len == 0)
  97   {
  98     bug("zero str_len in str_netfd_write");
  99   }
 100   retval = str_write_loop(p_str, fd);
 101   if (vsf_sysutil_retval_is_error(retval) || (unsigned int) retval != str_len)
 102   {
 103     ret = -1;
 104   }
 105   return ret;
 106 }
 107
 108 int
 109 str_netfd_read(struct mystr* p_str, int fd, unsigned int len)
 110 {
 111   int retval;
 112   str_reserve(p_str, len);
 113   str_trunc(p_str, len);
 114   retval = str_read_loop(p_str, fd);
 115   if (vsf_sysutil_retval_is_error(retval) || (unsigned int) retval != len)
 116   {
 117     return -1;
 118   }
 119   return retval;
 120 }
 121