src/usr.sbin/rpki-client/geofeed.c

308 lines
6.7 KiB
C

/* $OpenBSD: geofeed.c,v 1.15 2023/10/13 12:06:49 job Exp $ */
/*
* Copyright (c) 2022 Job Snijders <job@fastly.com>
* Copyright (c) 2019 Kristaps Dzonsons <kristaps@bsd.lv>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/socket.h>
#include <arpa/inet.h>
#include <ctype.h>
#include <err.h>
#include <stdlib.h>
#include <string.h>
#include <vis.h>
#include <openssl/bio.h>
#include <openssl/x509.h>
#include "extern.h"
struct parse {
const char *fn;
struct geofeed *res;
};
extern ASN1_OBJECT *geofeed_oid;
/*
* Take a CIDR prefix (in presentation format) and add it to parse results.
* Returns 1 on success, 0 on failure.
*/
static int
geofeed_parse_geoip(struct geofeed *res, char *cidr, char *loc)
{
struct geoip *geoip;
struct ip_addr *ipaddr;
enum afi afi;
int plen;
if ((ipaddr = calloc(1, sizeof(struct ip_addr))) == NULL)
err(1, NULL);
if ((plen = inet_net_pton(AF_INET, cidr, ipaddr->addr,
sizeof(ipaddr->addr))) != -1)
afi = AFI_IPV4;
else if ((plen = inet_net_pton(AF_INET6, cidr, ipaddr->addr,
sizeof(ipaddr->addr))) != -1)
afi = AFI_IPV6;
else {
static char buf[80];
if (strnvis(buf, cidr, sizeof(buf), VIS_SAFE)
>= (int)sizeof(buf)) {
memcpy(buf + sizeof(buf) - 4, "...", 4);
}
warnx("invalid address: %s", buf);
free(ipaddr);
return 0;
}
ipaddr->prefixlen = plen;
res->geoips = recallocarray(res->geoips, res->geoipsz,
res->geoipsz + 1, sizeof(struct geoip));
if (res->geoips == NULL)
err(1, NULL);
geoip = &res->geoips[res->geoipsz++];
if ((geoip->ip = calloc(1, sizeof(struct cert_ip))) == NULL)
err(1, NULL);
geoip->ip->type = CERT_IP_ADDR;
geoip->ip->ip = *ipaddr;
geoip->ip->afi = afi;
if ((geoip->loc = strdup(loc)) == NULL)
err(1, NULL);
if (!ip_cert_compose_ranges(geoip->ip))
return 0;
return 1;
}
/*
* Parse a full RFC 9092 file.
* Returns the Geofeed, or NULL if the object was malformed.
*/
struct geofeed *
geofeed_parse(X509 **x509, const char *fn, int talid, char *buf, size_t len)
{
struct parse p;
char *delim, *line, *loc, *nl;
ssize_t linelen;
BIO *bio;
char *b64 = NULL;
size_t b64sz = 0;
unsigned char *der = NULL;
size_t dersz;
struct cert *cert = NULL;
int rpki_signature_seen = 0, end_signature_seen = 0;
int rc = 0;
bio = BIO_new(BIO_s_mem());
if (bio == NULL)
errx(1, "BIO_new");
memset(&p, 0, sizeof(struct parse));
p.fn = fn;
if ((p.res = calloc(1, sizeof(struct geofeed))) == NULL)
err(1, NULL);
while ((nl = memchr(buf, '\n', len)) != NULL) {
line = buf;
/* advance buffer to next line */
len -= nl + 1 - buf;
buf = nl + 1;
/* replace LF and CR with NUL, point nl at first NUL */
*nl = '\0';
if (nl > line && nl[-1] == '\r') {
nl[-1] = '\0';
nl--;
linelen = nl - line;
} else {
warnx("%s: malformed file, expected CRLF line"
" endings", fn);
goto out;
}
if (end_signature_seen) {
warnx("%s: trailing data after signature section", fn);
goto out;
}
if (rpki_signature_seen) {
if (strncmp(line, "# End Signature:",
strlen("# End Signature:")) == 0) {
end_signature_seen = 1;
continue;
}
if (linelen > 74) {
warnx("%s: line in signature section too long",
fn);
goto out;
}
if (strncmp(line, "# ", strlen("# ")) != 0) {
warnx("%s: line in signature section too "
"short", fn);
goto out;
}
/* skip over "# " */
line += 2;
strlcat(b64, line, b64sz);
continue;
}
if (strncmp(line, "# RPKI Signature:",
strlen("# RPKI Signature:")) == 0) {
rpki_signature_seen = 1;
if ((b64 = calloc(1, len)) == NULL)
err(1, NULL);
b64sz = len;
continue;
}
/*
* Read the Geofeed CSV records into a BIO to later on
* calculate the message digest and compare with the one
* in the detached CMS signature.
*/
if (BIO_puts(bio, line) != linelen ||
BIO_puts(bio, "\r\n") != 2) {
warnx("%s: BIO_puts failed", fn);
goto out;
}
/* Zap comments and whitespace before them. */
delim = memchr(line, '#', linelen);
if (delim != NULL) {
while (delim > line &&
isspace((unsigned char)delim[-1]))
delim--;
*delim = '\0';
linelen = delim - line;
}
/* Skip empty lines. */
if (linelen == 0)
continue;
/* Split prefix and location info */
delim = memchr(line, ',', linelen);
if (delim != NULL) {
*delim = '\0';
loc = delim + 1;
} else
loc = "";
/* read each prefix */
if (!geofeed_parse_geoip(p.res, line, loc))
goto out;
}
if (!rpki_signature_seen || !end_signature_seen) {
warnx("%s: absent or invalid signature", fn);
goto out;
}
if ((base64_decode(b64, strlen(b64), &der, &dersz)) == -1) {
warnx("%s: base64_decode failed", fn);
goto out;
}
if (!cms_parse_validate_detached(x509, fn, der, dersz, geofeed_oid,
bio, &p.res->signtime))
goto out;
if (!x509_get_aia(*x509, fn, &p.res->aia))
goto out;
if (!x509_get_aki(*x509, fn, &p.res->aki))
goto out;
if (!x509_get_ski(*x509, fn, &p.res->ski))
goto out;
if (p.res->aia == NULL || p.res->aki == NULL || p.res->ski == NULL) {
warnx("%s: missing AIA, AKI, or SKI X509 extension", fn);
goto out;
}
if (!x509_get_notbefore(*x509, fn, &p.res->notbefore))
goto out;
if (!x509_get_notafter(*x509, fn, &p.res->notafter))
goto out;
if ((cert = cert_parse_ee_cert(fn, talid, *x509)) == NULL)
goto out;
if (x509_any_inherits(*x509)) {
warnx("%s: inherit elements not allowed in EE cert", fn);
goto out;
}
if (cert->asz > 0) {
warnx("%s: superfluous AS Resources extension present", fn);
goto out;
}
p.res->valid = valid_geofeed(fn, cert, p.res);
rc = 1;
out:
if (rc == 0) {
geofeed_free(p.res);
p.res = NULL;
X509_free(*x509);
*x509 = NULL;
}
cert_free(cert);
BIO_free(bio);
free(b64);
free(der);
return p.res;
}
/*
* Free what follows a pointer to a geofeed structure.
* Safe to call with NULL.
*/
void
geofeed_free(struct geofeed *p)
{
size_t i;
if (p == NULL)
return;
for (i = 0; i < p->geoipsz; i++) {
free(p->geoips[i].ip);
free(p->geoips[i].loc);
}
free(p->geoips);
free(p->aia);
free(p->aki);
free(p->ski);
free(p);
}