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Improved checking of required parameters for various claims with informative error reporting.

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This commit is contained in:
Cas Cremers 2012-05-01 16:37:18 +02:00
parent 8d0b704635
commit 6fabb3b1b4
1 changed files with 135 additions and 13 deletions
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148
src/compiler.c
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@ -483,6 +483,105 @@ isStringEqual (const char *s1, const char *s2)
return (strcmp (s1, s2) == 0);
}
//! Check sanity of the parameters occurring in a claim
/**
* Check if all variables have been received before.
* If not, aborts with error.
*/
void
checkParameterGround (Claimlist cl)
{
Termlist claimvars;
Termlist recvvars;
Termlist cli;
/* Compute received variables and those occurring in the claim parameter */
claimvars = termlistAddVariables (NULL, cl->parameter);
recvvars = compute_recv_variables (thisRole);
cli = claimvars;
while (cli != NULL)
{
if (!inTermlist (thisProtocol->rolenames, cli->term))
{
/* only if it is not a role */
if (!inTermlist (recvvars, cli->term))
{
/* this claimvar does not occur in the recvs? */
/* abort with error */
error_pre ();
globalError++;
eprintf ("Claim of role ");
termPrint (cl->rolename);
eprintf (" contains a variable ");
termPrint (cli->term);
eprintf
(" which is not initialized before (i.e., not received), on line %i.",
cl->lineno);
globalError--;
error_post ("");
}
}
cli = cli->next;
}
termlistDelete (claimvars);
termlistDelete (recvvars);
return;
}
//! Check if claim is of certain type, then check if meets parameter range, if not abort with error
void
checkParameterRange (const Claimlist cl, const Term claimtype, int minargs,
int maxargs)
{
Termlist params;
int num;
if (cl->type != claimtype)
{
return;
}
params = tuple_to_termlist (cl->parameter);
num = termlistLength (params);
if (minargs == -1)
{
minargs = num - 1;
}
if (maxargs == -1)
{
maxargs = num + 1;
}
if ((num < minargs) || (num > maxargs))
{
error_pre ();
globalError++;
termPrint (cl->type);
eprintf (" claim of role ");
termPrint (cl->rolename);
eprintf (" on line %i", cl->lineno);
if (maxargs == 0)
{
error_post (" does not require any arguments.");
}
else
{
if (num < minargs)
{
eprintf (" requires at least");
}
else
{
eprintf (" requires at most");
}
error_post (" %i arguments.", maxargs);
}
}
termlistDelete (params);
}
//! Create a claim and add it to the claims list, and add the role event.
Claimlist
claimCreate (const System sys, const Protocol protocol, const Role role,
@ -546,21 +645,23 @@ claimCreate (const System sys, const Protocol protocol, const Role role,
/* possible special handlers for each claim */
if (claim == CLAIM_Secret)
if ((claim == CLAIM_Secret) || (claim == CLAIM_SKR))
{
Termlist claimvars;
Termlist recvvars;
Termlist cli;
/* now check whether the claim contains variables that can actually be influenced by the intruder */
claimvars = termlistAddVariables (NULL, msg);
claimvars = termlistAddVariables (NULL, cl->parameter);
recvvars = compute_recv_variables (thisRole);
while (claimvars != NULL)
cli = claimvars;
while (cli != NULL)
{
if (!inTermlist (protocol->rolenames, claimvars->term))
if (!inTermlist (thisProtocol->rolenames, cli->term))
{
/* only if it is not a role */
if (!inTermlist (recvvars, claimvars->term))
if (!inTermlist (recvvars, cli->term))
{
/* this claimvar does not occur in the recvs? */
/* then we should ignore it later */
@ -569,20 +670,26 @@ claimCreate (const System sys, const Protocol protocol, const Role role,
/* show a warning for this */
globalError++;
eprintf ("warning: secrecy claim of role ");
warning_pre ();
eprintf ("Secrecy claim of role ");
termPrint (cl->rolename);
eprintf (" contains a variable ");
termPrint (claimvars->term);
termPrint (cli->term);
eprintf
(" which is never recv; therefore the claim will be true.\n");
(" which is never received; therefore the claim will be true.\n");
globalError--;
}
}
claimvars = claimvars->next;
cli = cli->next;
}
termlistDelete (claimvars);
termlistDelete (recvvars);
}
else
{
/* If it is NOT a SECRET claim, then check parameters are ground */
checkParameterGround (cl);
}
if ((claim == CLAIM_Commit) || (claim == CLAIM_Running))
{
@ -596,14 +703,17 @@ claimCreate (const System sys, const Protocol protocol, const Role role,
{
/* yield error */
globalError++;
eprintf ("warning: ");
warning_pre ();
termPrint (claim);
eprintf (" claim of role ");
termPrint (cl->rolename);
eprintf
(" requires four arguments. Please specify both the target role and the data to agree on, as in:\n");
warning_pre ();
eprintf (" claim(R, Commit, R', data )\n");
warning_pre ();
eprintf ("and\n");
warning_pre ();
eprintf (" claim(R', Running, R, data ).\n");
globalError--;
error
@ -620,16 +730,20 @@ claimCreate (const System sys, const Protocol protocol, const Role role,
{
/* yield error */
globalError++;
eprintf ("warning: ");
warning_pre ();
termPrint (claim);
eprintf (" claim of role ");
termPrint (cl->rolename);
eprintf (" specifies the target role to be '");
termPrint (targetrole);
eprintf ("', which is not a role name.\n");
warning_pre ();
eprintf ("Please use:\n");
warning_pre ();
eprintf (" claim(R, Commit, R', data )\n");
warning_pre ();
eprintf ("and\n");
warning_pre ();
eprintf (" claim(R', Running, R, data ).\n");
globalError--;
error
@ -637,8 +751,16 @@ claimCreate (const System sys, const Protocol protocol, const Role role,
lineno);
}
}
}
checkParameterRange (cl, CLAIM_Secret, 1, -1);
checkParameterRange (cl, CLAIM_SKR, 1, -1);
checkParameterRange (cl, CLAIM_Alive, 0, 0);
checkParameterRange (cl, CLAIM_Weakagree, 0, 0);
checkParameterRange (cl, CLAIM_Nisynch, 0, 0);
checkParameterRange (cl, CLAIM_Niagree, 0, 0);
checkParameterRange (cl, CLAIM_Empty, 0, 0);
checkParameterRange (cl, CLAIM_Reachable, 0, 0);
checkParameterRange (cl, CLAIM_SID, 1, -1);
return cl;
}
@ -831,7 +953,7 @@ commEvent (int event, Tac tc)
/* handles claim types with different syntactic claims */
if (claim == CLAIM_Secret)
if ((claim == CLAIM_Secret) || (claim == CLAIM_SKR))
{
if (n == 0)
{