1 files changed, 27 insertions, 121 deletions

diff --git a/src/common/util.c b/src/common/util.c
index f642c6a6dd..6a5b13e07a 100644
--- a/src/common/util.c
+++ b/src/common/util.c
@@ -27,6 +27,7 @@
 #include "sandbox.h"
 #include "backtrace.h"
 #include "util_process.h"
+#include "util_format.h"
 
 #ifdef _WIN32
 #include <io.h>
@@ -1063,6 +1064,9 @@ string_is_valid_ipv6_address(const char *string)
 
 /** Return true iff <b>string</b> matches a pattern of DNS names
  * that we allow Tor clients to connect to.
+ *
+ * Note: This allows certain technically invalid characters ('_') to cope
+ * with misconfigured zones that have been encountered in the wild.
  */
 int
 string_is_valid_hostname(const char *string)
@@ -1075,16 +1079,22 @@ string_is_valid_hostname(const char *string)
   smartlist_split_string(components,string,".",0,0);
 
   SMARTLIST_FOREACH_BEGIN(components, char *, c) {
-    if (c[0] == '-') {
+    if ((c[0] == '-') || (*c == '_')) {
       result = 0;
       break;
     }
 
+    /* Allow a single terminating '.' used rarely to indicate domains
+     * are FQDNs rather than relative. */
+    if ((c_sl_idx > 0) && (c_sl_idx + 1 == c_sl_len) && !*c) {
+      continue;
+    }
+
     do {
       if ((*c >= 'a' && *c <= 'z') ||
           (*c >= 'A' && *c <= 'Z') ||
           (*c >= '0' && *c <= '9') ||
-          (*c == '-'))
+          (*c == '-') || (*c == '_'))
         c++;
       else
         result = 0;
@@ -1229,91 +1239,6 @@ tor_parse_uint64(const char *s, int base, uint64_t min,
   CHECK_STRTOX_RESULT();
 }
 
-/** Encode the <b>srclen</b> bytes at <b>src</b> in a NUL-terminated,
- * uppercase hexadecimal string; store it in the <b>destlen</b>-byte buffer
- * <b>dest</b>.
- */
-void
-base16_encode(char *dest, size_t destlen, const char *src, size_t srclen)
-{
-  const char *end;
-  char *cp;
-
-  tor_assert(destlen >= srclen*2+1);
-  tor_assert(destlen < SIZE_T_CEILING);
-
-  cp = dest;
-  end = src+srclen;
-  while (src<end) {
-    *cp++ = "0123456789ABCDEF"[ (*(const uint8_t*)src) >> 4 ];
-    *cp++ = "0123456789ABCDEF"[ (*(const uint8_t*)src) & 0xf ];
-    ++src;
-  }
-  *cp = '\0';
-}
-
-/** Helper: given a hex digit, return its value, or -1 if it isn't hex. */
-static INLINE int
-hex_decode_digit_(char c)
-{
-  switch (c) {
-    case '0': return 0;
-    case '1': return 1;
-    case '2': return 2;
-    case '3': return 3;
-    case '4': return 4;
-    case '5': return 5;
-    case '6': return 6;
-    case '7': return 7;
-    case '8': return 8;
-    case '9': return 9;
-    case 'A': case 'a': return 10;
-    case 'B': case 'b': return 11;
-    case 'C': case 'c': return 12;
-    case 'D': case 'd': return 13;
-    case 'E': case 'e': return 14;
-    case 'F': case 'f': return 15;
-    default:
-      return -1;
-  }
-}
-
-/** Helper: given a hex digit, return its value, or -1 if it isn't hex. */
-int
-hex_decode_digit(char c)
-{
-  return hex_decode_digit_(c);
-}
-
-/** Given a hexadecimal string of <b>srclen</b> bytes in <b>src</b>, decode it
- * and store the result in the <b>destlen</b>-byte buffer at <b>dest</b>.
- * Return 0 on success, -1 on failure. */
-int
-base16_decode(char *dest, size_t destlen, const char *src, size_t srclen)
-{
-  const char *end;
-
-  int v1,v2;
-  if ((srclen % 2) != 0)
-    return -1;
-  if (destlen < srclen/2 || destlen > SIZE_T_CEILING)
-    return -1;
-
-  memset(dest, 0, destlen);
-
-  end = src+srclen;
-  while (src<end) {
-    v1 = hex_decode_digit_(*src);
-    v2 = hex_decode_digit_(*(src+1));
-    if (v1<0||v2<0)
-      return -1;
-    *(uint8_t*)dest = (v1<<4)|v2;
-    ++dest;
-    src+=2;
-  }
-  return 0;
-}
-
 /** Allocate and return a new string representing the contents of <b>s</b>,
  * surrounded by quotes and using standard C escapes.
  *
@@ -2021,8 +1946,10 @@ read_all(tor_socket_t fd, char *buf, size_t count, int isSocket)
   size_t numread = 0;
   ssize_t result;
 
-  if (count > SIZE_T_CEILING || count > SSIZE_MAX)
+  if (count > SIZE_T_CEILING || count > SSIZE_MAX) {
+    errno = EINVAL;
     return -1;
+  }
 
   while (numread != count) {
     if (isSocket)
@@ -2582,8 +2509,10 @@ read_file_to_str_until_eof(int fd, size_t max_bytes_to_read, size_t *sz_out)
   char *string = NULL;
   size_t string_max = 0;
 
-  if (max_bytes_to_read+1 >= SIZE_T_CEILING)
+  if (max_bytes_to_read+1 >= SIZE_T_CEILING) {
+    errno = EINVAL;
     return NULL;
+  }
 
   do {
     /* XXXX This "add 1K" approach is a little goofy; if we care about
@@ -2595,7 +2524,9 @@ read_file_to_str_until_eof(int fd, size_t max_bytes_to_read, size_t *sz_out)
     string = tor_realloc(string, string_max);
     r = read(fd, string + pos, string_max - pos - 1);
     if (r < 0) {
+      int save_errno = errno;
       tor_free(string);
+      errno = save_errno;
       return NULL;
     }
 
@@ -2663,17 +2594,21 @@ read_file_to_str(const char *filename, int flags, struct stat *stat_out)
   if (S_ISFIFO(statbuf.st_mode)) {
     size_t sz = 0;
     string = read_file_to_str_until_eof(fd, FIFO_READ_MAX, &sz);
+    int save_errno = errno;
     if (string && stat_out) {
       statbuf.st_size = sz;
       memcpy(stat_out, &statbuf, sizeof(struct stat));
     }
     close(fd);
+    if (!string)
+      errno = save_errno;
     return string;
   }
 #endif
 
   if ((uint64_t)(statbuf.st_size)+1 >= SIZE_T_CEILING) {
     close(fd);
+    errno = EINVAL;
     return NULL;
   }
 
@@ -2843,38 +2778,9 @@ parse_config_line_from_str_verbose(const char *line, char **key_out,
                                    char **value_out,
                                    const char **err_out)
 {
-  /* I believe the file format here is supposed to be:
-     FILE = (EMPTYLINE | LINE)* (EMPTYLASTLINE | LASTLINE)?
-
-     EMPTYLASTLINE = SPACE* | COMMENT
-     EMPTYLINE = EMPTYLASTLINE NL
-     SPACE = ' ' | '\r' | '\t'
-     COMMENT = '#' NOT-NL*
-     NOT-NL = Any character except '\n'
-     NL = '\n'
-
-     LASTLINE = SPACE* KEY SPACE* VALUES
-     LINE = LASTLINE NL
-     KEY = KEYCHAR+
-     KEYCHAR = Any character except ' ', '\r', '\n', '\t', '#', "\"
-
-     VALUES = QUOTEDVALUE | NORMALVALUE
-     QUOTEDVALUE = QUOTE QVCHAR* QUOTE EOLSPACE?
-     QUOTE = '"'
-     QVCHAR = KEYCHAR | ESC ('n' | 't' | 'r' | '"' | ESC |'\'' | OCTAL | HEX)
-     ESC = "\\"
-     OCTAL = ODIGIT (ODIGIT ODIGIT?)?
-     HEX = ('x' | 'X') HEXDIGIT HEXDIGIT
-     ODIGIT = '0' .. '7'
-     HEXDIGIT = '0'..'9' | 'a' .. 'f' | 'A' .. 'F'
-     EOLSPACE = SPACE* COMMENT?
-
-     NORMALVALUE = (VALCHAR | ESC ESC_IGNORE | CONTINUATION)* EOLSPACE?
-     VALCHAR = Any character except ESC, '#', and '\n'
-     ESC_IGNORE = Any character except '#' or '\n'
-     CONTINUATION = ESC NL ( COMMENT NL )*
+  /*
+    See torrc_format.txt for a description of the (silly) format this parses.
    */
-
   const char *key, *val, *cp;
   int continuation = 0;
 
@@ -3582,7 +3488,7 @@ finish_daemon(const char *cp)
 /** Write the current process ID, followed by NL, into <b>filename</b>.
  */
 void
-write_pidfile(char *filename)
+write_pidfile(const char *filename)
 {
   FILE *pidfile;