/* This file is part of Eclat.
Copyright (C) 2012, 2013 Sergey Poznyakoff.
Eclat is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
Eclat is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with Eclat. If not, see . */
#include
#include
#include
#include "libeclat.h"
#include "sha256.h"
#include "grecs.h"
struct pname {
size_t i;
char **a;
};
static int
get_param_name(void *sym, void *data)
{
struct grecs_syment *se = sym;
struct pname *pn = data;
pn->a[pn->i++] = se->name;
return 0;
}
static int
compnames(const void *a, const void *b)
{
char * const *ac = a;
char * const *bc = b;
return strcmp(*ac, *bc);
}
static void
querysign2(struct ec2_query *req, char *secret)
{
char **pnames;
size_t i, n;
struct grecs_txtacc *acc;
struct pname pn;
char *str;
char digest[SHA256_DIGEST_SIZE];
size_t siglen;
const char *verb;
char tsbuf[22];
time_t t;
acc = grecs_txtacc_create();
/* Add default parameters */
eclat_query_add_param(req, "SignatureMethod", "HmacSHA256");
eclat_query_add_param(req, "SignatureVersion", "2");
time(&t);
strftime(tsbuf, sizeof(tsbuf), "%Y-%m-%dT%H:%M:%SZ", gmtime(&t));
eclat_query_add_param(req, "Timestamp", tsbuf);
eclat_query_encode(req);
/* Collect and sort parameter names */
n = grecs_symtab_count_entries(req->params);
pnames = grecs_calloc(n, sizeof(pnames[0]));
pn.i = 0;
pn.a = pnames;
grecs_symtab_enumerate(req->params, get_param_name, &pn);
qsort(pnames, n, sizeof(pnames[0]), compnames);
verb = (req->flags & EC2_QF_POST) ? "POST" : "GET";
grecs_txtacc_grow(acc, verb, strlen(verb));
grecs_txtacc_grow_char(acc, '\n');
grecs_txtacc_grow(acc, req->endpoint, strlen(req->endpoint));
grecs_txtacc_grow_char(acc, '\n');
grecs_txtacc_grow(acc, req->uri, strlen(req->uri));
grecs_txtacc_grow_char(acc, '\n');
/* Append a canonicalized query string */
for (i = 0; i < n; i++) {
struct ec2_param *p, key;
key.name = pnames[i];
p = grecs_symtab_lookup_or_install(req->params, &key, NULL);
if (!p)
abort();
if (i != 0)
grecs_txtacc_grow_char(acc, '&');
grecs_txtacc_grow(acc, p->name, strlen(p->name));
if (p->value) {
grecs_txtacc_grow_char(acc, '=');
grecs_txtacc_grow(acc, p->value, strlen(p->value));
}
}
grecs_txtacc_grow_char(acc, 0);
str = grecs_txtacc_finish(acc, 0);
hmac_sha256(str, strlen(str), secret, strlen(secret), digest);
eclat_base64_encode((unsigned char *)digest, sizeof(digest),
(unsigned char**) &req->signature, &siglen);
grecs_txtacc_free(acc);
free(pnames);
/*FIXME
t += req->ttl;
strftime(tsbuf, sizeof(tsbuf), "%Y-%m-%dT%H:%M:%SZ", gmtime(&t));
eclat_query_add_param(req, "Expires", tsbuf);
*/
}
static void
querysign4(struct ec2_query *req, char *secret)
{
abort();
}
struct qsimpl {
char *qs_version;
void (*qs_fun)(struct ec2_query *, char *);
};
static struct qsimpl qstab[] = {
{ "2", querysign2 },
{ "4", querysign4 },
{ NULL }
};
void
eclat_query_sign(struct ec2_query *req, char *secret, char *version)
{
struct qsimpl *qs;
for (qs = qstab; qs->qs_version && strcmp(qs->qs_version, version);
qs++)
;
if (qs->qs_version)
qs->qs_fun(req, secret);
else {
err("INTERNAL ERROR: unsupported version %s", version);
abort();
}
}