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authorWerner Koch <[email protected]>2007-12-12 16:47:52 +0000
committerWerner Koch <[email protected]>2007-12-12 16:47:52 +0000
commit56bd419029acdd034af6b51b543675700201c7fe (patch)
treed4554573a8aa1234aeb9954db6f83121aaba1ce2 /g10/trustdb.c
parentSupport DSA2. (diff)
downloadgnupg-56bd419029acdd034af6b51b543675700201c7fe.tar.gz
gnupg-56bd419029acdd034af6b51b543675700201c7fe.zip
Doc fixes.
Add more files to POTFILES. Protect against malloc bombs.
Diffstat (limited to 'g10/trustdb.c')
-rw-r--r--g10/trustdb.c99
1 files changed, 88 insertions, 11 deletions
diff --git a/g10/trustdb.c b/g10/trustdb.c
index 62eafba0d..ff218ad80 100644
--- a/g10/trustdb.c
+++ b/g10/trustdb.c
@@ -1,6 +1,6 @@
/* trustdb.c
- * Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004,
- * 2005 Free Software Foundation, Inc.
+ * Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
+ * 2007 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
@@ -1745,6 +1745,71 @@ clean_key(KBNODE keyblock,int noisy,int self_only,
uids_cleaned,sigs_cleaned);
}
+/* Returns a sanitized copy of the regexp (which might be "", but not
+ NULL). */
+#ifndef DISABLE_REGEX
+static char *
+sanitize_regexp(const char *old)
+{
+ size_t start=0,len=strlen(old),idx=0;
+ int escaped=0,standard_bracket=0;
+ char *new=xmalloc((len*2)+1); /* enough to \-escape everything if we
+ have to */
+
+ /* There are basically two commonly-used regexps here. GPG and most
+ versions of PGP use "<[^>]+[@.]example\.com>$" and PGP (9)
+ command line uses "example.com" (i.e. whatever the user specfies,
+ and we can't expect users know to use "\." instead of "."). So
+ here are the rules: we're allowed to start with "<[^>]+[@.]" and
+ end with ">$" or start and end with nothing. In between, the
+ only legal regex character is ".", and everything else gets
+ escaped. Part of the gotcha here is that some regex packages
+ allow more than RFC-4880 requires. For example, 4880 has no "{}"
+ operator, but GNU regex does. Commenting removes these operators
+ from consideration. A possible future enhancement is to use
+ commenting to effectively back off a given regex to the Henry
+ Spencer syntax in 4880. -dshaw */
+
+ /* Are we bracketed between "<[^>]+[@.]" and ">$" ? */
+ if(len>=12 && strncmp(old,"<[^>]+[@.]",10)==0
+ && old[len-2]=='>' && old[len-1]=='$')
+ {
+ strcpy(new,"<[^>]+[@.]");
+ idx=strlen(new);
+ standard_bracket=1;
+ start+=10;
+ len-=2;
+ }
+
+ /* Walk the remaining characters and ensure that everything that is
+ left is not an operational regex character. */
+ for(;start<len;start++)
+ {
+ if(!escaped && old[start]=='\\')
+ escaped=1;
+ else if(!escaped && old[start]!='.')
+ new[idx++]='\\';
+ else
+ escaped=0;
+
+ new[idx++]=old[start];
+ }
+
+ new[idx]='\0';
+
+ /* Note that the (sub)string we look at might end with a bare "\".
+ If it does, leave it that way. If the regexp actually ended with
+ ">$", then it was escaping the ">" and is fine. If the regexp
+ actually ended with the bare "\", then it's an illegal regexp and
+ regcomp should kick it out. */
+
+ if(standard_bracket)
+ strcat(new,">$");
+
+ return new;
+}
+#endif /*!DISABLE_REGEX*/
+
/* Used by validate_one_keyblock to confirm a regexp within a trust
signature. Returns 1 for match, and 0 for no match or regex
error. */
@@ -1755,23 +1820,35 @@ check_regexp(const char *expr,const char *string)
/* When DISABLE_REGEX is defined, assume all regexps do not
match. */
return 0;
-#elif defined(__riscos__)
- return riscos_check_regexp(expr, string, DBG_TRUST);
#else
int ret;
- regex_t pat;
+ char *regexp;
- if(regcomp(&pat,expr,REG_ICASE|REG_NOSUB|REG_EXTENDED)!=0)
- return 0;
+ regexp=sanitize_regexp(expr);
- ret=regexec(&pat,string,0,NULL,0);
+#ifdef __riscos__
+ ret=riscos_check_regexp(expr, string, DBG_TRUST);
+#else
+ {
+ regex_t pat;
- regfree(&pat);
+ ret=regcomp(&pat,regexp,REG_ICASE|REG_NOSUB|REG_EXTENDED);
+ if(ret==0)
+ {
+ ret=regexec(&pat,string,0,NULL,0);
+ regfree(&pat);
+ ret=(ret==0);
+ }
+ }
+#endif
if(DBG_TRUST)
- log_debug("regexp `%s' on `%s': %s\n",expr,string,ret==0?"YES":"NO");
+ log_debug("regexp `%s' (`%s') on `%s': %s\n",
+ regexp,expr,string,ret==0?"YES":"NO");
+
+ xfree(regexp);
- return (ret==0);
+ return ret;
#endif
}