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minix/crypto/external/bsd/netpgp/dist/src/libverify/libverify.c
Lionel Sambuc 0a6a1f1d05 NetBSD re-synchronization of the source tree 
This brings our tree to NetBSD 7.0, as found on -current on the
10-10-2015.

This updates:
 - LLVM to 3.6.1
 - GCC to GCC 5.1
 - Replace minix/commands/zdump with usr.bin/zdump
 - external/bsd/libelf has moved to /external/bsd/elftoolchain/
 - Import ctwm
 - Drop sprintf from libminc

Change-Id: I149836ac18e9326be9353958bab9b266efb056f0
2016-01-13 20:32:14 +01:00

2374 lines
64 KiB
C
Raw Blame History

/*-
* Copyright (c) 2012 Alistair Crooks <agc@NetBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/param.h>
#include <sys/mman.h>
#include <bzlib.h>
#include <err.h>
#include <inttypes.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <zlib.h>
#include "array.h"
#include "bn.h"
#include "b64.h"
#include "digest.h"
#include "pgpsum.h"
#include "rsa.h"
#include "verify.h"
#ifndef USE_ARG
#define USE_ARG(x) /*LINTED*/(void)&(x)
#endif
#ifndef __printflike
#define __printflike(n, m) __attribute__((format(printf,n,m)))
#endif
#define BITS_TO_BYTES(b) (((b) + (CHAR_BIT - 1)) / CHAR_BIT)
/* packet types */
#define SIGNATURE_PKT 2
#define ONEPASS_SIGNATURE_PKT 4
#define PUBKEY_PKT 6
#define COMPRESSED_DATA_PKT 8
#define MARKER_PKT 10
#define LITDATA_PKT 11
#define TRUST_PKT 12
#define USERID_PKT 13
#define PUB_SUBKEY_PKT 14
#define USER_ATTRIBUTE_PKT 17
/* only allow certain packets at certain times */
#define PUBRING_ALLOWED "\002\006\014\015\016\021"
#define SIGNATURE_ALLOWED "\002\004\010\013"
/* actions to do on close */
#define FREE_MEM 0x01
#define UNMAP_MEM 0x02
/* types of pubkey we encounter */
#define PUBKEY_RSA_ENCRYPT_OR_SIGN 1
#define PUBKEY_RSA_ENCRYPT 2
#define PUBKEY_RSA_SIGN 3
#define PUBKEY_ELGAMAL_ENCRYPT 16
#define PUBKEY_DSA 17
#define PUBKEY_ELLIPTIC_CURVE 18
#define PUBKEY_ECDSA 19
#define PUBKEY_ELGAMAL_ENCRYPT_OR_SIGN 20
/* hash algorithm definitions */
#define PGPV_HASH_MD5 1
#define PGPV_HASH_SHA1 2
#define PGPV_HASH_RIPEMD 3
#define PGPV_HASH_SHA256 8
#define PGPV_HASH_SHA384 9
#define PGPV_HASH_SHA512 10
/* pubkey defs for bignums */
#define RSA_N 0
#define RSA_E 1
#define DSA_P 0
#define DSA_Q 1
#define DSA_G 2
#define DSA_Y 3
#define ELGAMAL_P 0
#define ELGAMAL_G 1
#define ELGAMAL_Y 2
/* sesskey indices */
#define RSA_SESSKEY_ENCRYPTED_M 0
#define RSA_SESSKEY_M 1
#define ELGAMAL_SESSKEY_G_TO_K 0
#define ELGAMAL_SESSKEY_ENCRYPTED_M 1
/* seckey indices */
#define RSA_SECKEY_D 0
#define RSA_SECKEY_P 1
#define RSA_SECKEY_Q 2
#define RSA_SECKEY_U 3
#define DSA_SECKEY_X 0
#define ELGAMAL_SECKEY_X 0
/* signature mpi indices in bignumber array */
#define RSA_SIG 0
#define DSA_R 0
#define DSA_S 1
#define ELGAMAL_SIG_R 0
#define ELGAMAL_SIG_S 1
/* signature types */
#define SIGTYPE_BINARY_DOC 0x00 /* Signature of a binary document */
#define SIGTYPE_TEXT 0x01 /* Signature of a canonical text document */
#define SIGTYPE_STANDALONE 0x02 /* Standalone signature */
#define SIGTYPE_GENERIC_USERID 0x10 /* Generic certification of a User ID and Public Key packet */
#define SIGTYPE_PERSONA_USERID 0x11 /* Persona certification of a User ID and Public Key packet */
#define SIGTYPE_CASUAL_USERID 0x12 /* Casual certification of a User ID and Public Key packet */
#define SIGTYPE_POSITIVE_USERID 0x13 /* Positive certification of a User ID and Public Key packet */
#define SIGTYPE_SUBKEY_BINDING 0x18 /* Subkey Binding Signature */
#define SIGTYPE_PRIMARY_KEY_BINDING 0x19 /* Primary Key Binding Signature */
#define SIGTYPE_DIRECT_KEY 0x1f /* Signature directly on a key */
#define SIGTYPE_KEY_REVOCATION 0x20 /* Key revocation signature */
#define SIGTYPE_SUBKEY_REVOCATION 0x28 /* Subkey revocation signature */
#define SIGTYPE_CERT_REVOCATION 0x30 /* Certification revocation signature */
#define SIGTYPE_TIMESTAMP_SIG 0x40 /* Timestamp signature */
#define SIGTYPE_3RDPARTY 0x50 /* Third-Party Confirmation signature */
/* Forward declarations */
static int read_all_packets(pgpv_t */*pgp*/, pgpv_mem_t */*mem*/, const char */*op*/);
static int read_binary_file(pgpv_t */*pgp*/, const char */*op*/, const char */*fmt*/, ...)
__printflike(3, 4);
static int read_binary_memory(pgpv_t */*pgp*/, const char */*op*/, const void */*memory*/, size_t /*size*/);
static int pgpv_find_keyid(pgpv_t */*pgp*/, const char */*strkeyid*/, uint8_t */*keyid*/);
/* read a file into the pgpv_mem_t struct */
static int
read_file(pgpv_t *pgp, const char *f)
{
struct stat st;
pgpv_mem_t *mem;
ARRAY_EXPAND(pgp->areas);
ARRAY_COUNT(pgp->areas) += 1;
mem = &ARRAY_LAST(pgp->areas);
memset(mem, 0x0, sizeof(*mem));
if ((mem->fp = fopen(f, "r")) == NULL) {
warn("can't read '%s'", f);
return 0;
}
fstat(fileno(mem->fp), &st);
mem->size = (size_t)st.st_size;
mem->mem = mmap(NULL, mem->size, PROT_READ, MAP_SHARED, fileno(mem->fp), 0);
mem->dealloc = UNMAP_MEM;
return 1;
}
/* DTRT and free resources */
static int
closemem(pgpv_mem_t *mem)
{
switch(mem->dealloc) {
case FREE_MEM:
free(mem->mem);
mem->size = 0;
break;
case UNMAP_MEM:
munmap(mem->mem, mem->size);
fclose(mem->fp);
break;
}
return 1;
}
/* make a reference to a memory area, and its offset */
static void
make_ref(pgpv_t *pgp, uint8_t mement, pgpv_ref_t *ref)
{
ref->mem = mement;
ref->offset = ARRAY_ELEMENT(pgp->areas, ref->mem).cc;
ref->vp = pgp;
}
/* return the pointer we wanted originally */
static uint8_t *
get_ref(pgpv_ref_t *ref)
{
pgpv_mem_t *mem;
pgpv_t *pgp = (pgpv_t *)ref->vp;;
mem = &ARRAY_ELEMENT(pgp->areas, ref->mem);
return &mem->mem[ref->offset];
}
#define IS_PARTIAL(x) ((x) >= 224 && (x) < 255)
#define DECODE_PARTIAL(x) (1 << ((x) & 0x1f))
#define PKT_LENGTH(m, off) \
((m[off] < 192) ? (m[off]) : \
(m[off] < 224) ? ((m[off] - 192) << 8) + (m[off + 1]) + 192 : \
(m[off + 1] << 24) | ((m[off + 2]) << 16) | ((m[off + 3]) << 8) | (m[off + 4]))
#define PKT_LENGTH_LENGTH(m, off) \
((m[off] < 192) ? 1 : (m[off] < 224) ? 2 : 5)
/* fix up partial body lengths, return new size */
static size_t
fixup_partials(pgpv_t *pgp, uint8_t *p, size_t totlen, size_t filesize, size_t *cc)
{
pgpv_mem_t *mem;
size_t partial;
size_t newcc;
if (totlen > filesize) {
printf("fixup_partial: filesize %zu is less than encoded size %zu\n", filesize, totlen);
return 0;
}
ARRAY_EXPAND(pgp->areas);
ARRAY_COUNT(pgp->areas) += 1;
mem = &ARRAY_LAST(pgp->areas);
mem->size = totlen;
if ((mem->mem = calloc(1, mem->size + 5)) == NULL) {
printf("fixup_partial: can't allocate %zu length\n", totlen);
return 0;
}
newcc = 0;
mem->dealloc = FREE_MEM;
for (*cc = 0 ; *cc < totlen ; newcc += partial, *cc += partial + 1) {
if (IS_PARTIAL(p[*cc])) {
partial = DECODE_PARTIAL(p[*cc]);
memcpy(&mem->mem[newcc], &p[*cc + 1], partial);
} else {
partial = PKT_LENGTH(p, *cc);
*cc += PKT_LENGTH_LENGTH(p, *cc);
memcpy(&mem->mem[newcc], &p[*cc], partial);
newcc += partial;
*cc += partial;
break;
}
}
return newcc;
}
/* get the weirdo packet length */
static size_t
get_pkt_len(uint8_t newfmt, uint8_t *p, size_t filesize, int isprimary)
{
size_t lenbytes;
size_t len;
if (newfmt) {
if (IS_PARTIAL(*p)) {
if (!isprimary) {
/* for sub-packets, only 1, 2 or 4 byte sizes allowed */
return ((*p - 192) << 8) + *(p + 1) + 192;
}
lenbytes = 1;
for (len = DECODE_PARTIAL(*p) ; IS_PARTIAL(p[len + lenbytes]) ; lenbytes++) {
len += DECODE_PARTIAL(p[len + lenbytes]);
}
len += get_pkt_len(newfmt, &p[len + lenbytes], filesize, 1);
return len;
}
return PKT_LENGTH(p, 0);
} else {
switch(*--p & 0x3) {
case 0:
return *(p + 1);
case 1:
return (*(p + 1) << 8) | *(p + 2);
case 2:
return (*(p + 1) << 24) | (*(p + 2) << 16) | (*(p + 3) << 8) | *(p + 4);
default:
return filesize;
}
}
}
/* get the length of the packet length field */
static unsigned
get_pkt_len_len(uint8_t newfmt, uint8_t *p, int isprimary)
{
if (newfmt) {
if (IS_PARTIAL(*p)) {
return (isprimary) ? 1 : 2;
}
return PKT_LENGTH_LENGTH(p, 0);
} else {
switch(*--p & 0x3) {
case 0:
return 1;
case 1:
return 2;
case 2:
return 4;
default:
return 0;
}
}
}
/* copy the 32bit integer in memory in network order */
static unsigned
fmt_32(uint8_t *p, uint32_t a)
{
a = htonl(a);
memcpy(p, &a, sizeof(a));
return sizeof(a);
}
/* copy the 16bit integer in memory in network order */
static unsigned
fmt_16(uint8_t *p, uint16_t a)
{
a = htons(a);
memcpy(p, &a, sizeof(a));
return sizeof(a);
}
/* format a binary string in memory */
static size_t
fmt_binary(char *s, size_t size, const uint8_t *bin, unsigned len)
{
unsigned i;
size_t cc;
for (cc = 0, i = 0 ; i < len && cc < size ; i++) {
cc += snprintf(&s[cc], size - cc, "%02x", bin[i]);
}
return cc;
}
/* format an mpi into memory */
static unsigned
fmt_binary_mpi(pgpv_bignum_t *mpi, uint8_t *p, size_t size)
{
unsigned bytes;
BIGNUM *bn;
bytes = BITS_TO_BYTES(mpi->bits);
if ((size_t)bytes + 2 + 1 > size) {
warn("truncated mpi");
return 0;
}
bn = (BIGNUM *)mpi->bn;
if (bn == NULL || BN_is_zero(bn)) {
fmt_32(p, 0);
return 2 + 1;
}
fmt_16(p, mpi->bits);
BN_bn2bin(bn, &p[2]);
return bytes + 2;
}
/* dump an mpi value onto stdout */
static size_t
fmt_mpi(char *s, size_t size, pgpv_bignum_t *bn, const char *name, int pbits)
{
size_t cc;
char *buf;
cc = snprintf(s, size, "%s=", name);
if (pbits) {
cc += snprintf(&s[cc], size - cc, "[%u bits] ", bn->bits);
}
buf = BN_bn2hex(bn->bn);
cc += snprintf(&s[cc], size - cc, "%s\n", buf);
free(buf);
return cc;
}
#define ALG_IS_RSA(alg) (((alg) == PUBKEY_RSA_ENCRYPT_OR_SIGN) || \
((alg) == PUBKEY_RSA_ENCRYPT) || \
((alg) == PUBKEY_RSA_SIGN))
#define ALG_IS_DSA(alg) ((alg) == PUBKEY_DSA)
/* format key mpis into memory */
static unsigned
fmt_key_mpis(pgpv_pubkey_t *pubkey, uint8_t *buf, size_t size)
{
size_t cc;
cc = 0;
buf[cc++] = pubkey->version;
cc += fmt_32(&buf[cc], (uint32_t)pubkey->birth);
buf[cc++] = pubkey->keyalg;
switch(pubkey->keyalg) {
case PUBKEY_RSA_ENCRYPT_OR_SIGN:
case PUBKEY_RSA_ENCRYPT:
case PUBKEY_RSA_SIGN:
cc += fmt_binary_mpi(&pubkey->bn[RSA_N], &buf[cc], size - cc);
cc += fmt_binary_mpi(&pubkey->bn[RSA_E], &buf[cc], size - cc);
break;
case PUBKEY_DSA:
cc += fmt_binary_mpi(&pubkey->bn[DSA_P], &buf[cc], size - cc);
cc += fmt_binary_mpi(&pubkey->bn[DSA_Q], &buf[cc], size - cc);
cc += fmt_binary_mpi(&pubkey->bn[DSA_G], &buf[cc], size - cc);
cc += fmt_binary_mpi(&pubkey->bn[DSA_Y], &buf[cc], size - cc);
break;
default:
cc += fmt_binary_mpi(&pubkey->bn[ELGAMAL_P], &buf[cc], size - cc);
cc += fmt_binary_mpi(&pubkey->bn[ELGAMAL_G], &buf[cc], size - cc);
cc += fmt_binary_mpi(&pubkey->bn[ELGAMAL_Y], &buf[cc], size - cc);
break;
}
return (unsigned)cc;
}
/* calculate the fingerprint, RFC 4880, section 12.2 */
static int
pgpv_calc_fingerprint(pgpv_fingerprint_t *fingerprint, pgpv_pubkey_t *pubkey)
{
digest_t fphash;
uint16_t cc;
uint8_t ch = 0x99;
uint8_t buf[8192 + 2 + 1];
uint8_t len[2];
memset(&fphash, 0x0, sizeof(fphash));
if (pubkey->version == 4) {
/* v4 keys */
fingerprint->hashalg = digest_get_alg("sha1");
digest_init(&fphash, (unsigned)fingerprint->hashalg);
cc = fmt_key_mpis(pubkey, buf, sizeof(buf));
digest_update(&fphash, &ch, 1);
fmt_16(len, cc);
digest_update(&fphash, len, 2);
digest_update(&fphash, buf, cc);
fingerprint->len = digest_final(fingerprint->v, &fphash);
return 1;
}
if (ALG_IS_RSA(pubkey->keyalg)) {
/* v3 keys are RSA */
fingerprint->hashalg = digest_get_alg("md5");
digest_init(&fphash, (unsigned)fingerprint->hashalg);
if (pubkey->bn[RSA_N].bn && pubkey->bn[RSA_E].bn) {
cc = fmt_binary_mpi(&pubkey->bn[RSA_N], buf, sizeof(buf));
digest_update(&fphash, &buf[2], cc - 2);
cc = fmt_binary_mpi(&pubkey->bn[RSA_E], buf, sizeof(buf));
digest_update(&fphash, &buf[2], cc - 2);
fingerprint->len = digest_final(fingerprint->v, &fphash);
return 1;
}
}
if (pubkey->bn[RSA_N].bn) {
if ((cc = fmt_binary_mpi(&pubkey->bn[RSA_N], buf, sizeof(buf))) >= PGPV_KEYID_LEN) {
memcpy(fingerprint->v, &buf[cc - PGPV_KEYID_LEN], PGPV_KEYID_LEN);
fingerprint->len = PGPV_KEYID_LEN;
return 1;
}
}
/* exhausted all avenues, really */
memset(fingerprint->v, 0xff, fingerprint->len = PGPV_KEYID_LEN);
return 1;
}
/* format a fingerprint into memory */
static size_t
fmt_fingerprint(char *s, size_t size, pgpv_fingerprint_t *fingerprint, const char *name)
{
unsigned i;
size_t cc;
cc = snprintf(s, size, "%s ", name);
for (i = 0 ; i < fingerprint->len ; i++) {
cc += snprintf(&s[cc], size - cc, "%02hhx%s",
fingerprint->v[i], (i % 2 == 1) ? " " : "");
}
cc += snprintf(&s[cc], size - cc, "\n");
return cc;
}
/* calculate keyid from a pubkey */
static int
pgpv_calc_keyid(pgpv_pubkey_t *key)
{
pgpv_calc_fingerprint(&key->fingerprint, key);
memcpy(key->keyid, &key->fingerprint.v[key->fingerprint.len - PGPV_KEYID_LEN], PGPV_KEYID_LEN);
return 1;
}
/* convert a hex string to a 64bit key id (in big endian byte order */
static void
str_to_keyid(const char *s, uint8_t *keyid)
{
uint64_t u64;
u64 = (uint64_t)strtoull(s, NULL, 16);
u64 = ((u64 & 0x00000000000000FFUL) << 56) |
((u64 & 0x000000000000FF00UL) << 40) |
((u64 & 0x0000000000FF0000UL) << 24) |
((u64 & 0x00000000FF000000UL) << 8) |
((u64 & 0x000000FF00000000UL) >> 8) |
((u64 & 0x0000FF0000000000UL) >> 24) |
((u64 & 0x00FF000000000000UL) >> 40) |
((u64 & 0xFF00000000000000UL) >> 56);
memcpy(keyid, &u64, PGPV_KEYID_LEN);
}
#define PKT_ALWAYS_ON 0x80
#define PKT_NEWFMT_MASK 0x40
#define PKT_NEWFMT_TAG_MASK 0x3f
#define PKT_OLDFMT_TAG_MASK 0x3c
#define SUBPKT_CRITICAL_MASK 0x80
#define SUBPKT_TAG_MASK 0x7f
#define SUBPKT_SIG_BIRTH 2
#define SUBPKT_SIG_EXPIRY 3
#define SUBPKT_EXPORT_CERT 4
#define SUBPKT_TRUST_SIG 5
#define SUBPKT_REGEXP 6
#define SUBPKT_REVOCABLE 7
#define SUBPKT_KEY_EXPIRY 9
#define SUBPKT_BWD_COMPAT 10
#define SUBPKT_PREF_SYMMETRIC_ALG 11
#define SUBPKT_REVOCATION_KEY 12
#define SUBPKT_ISSUER 16
#define SUBPKT_NOTATION 20
#define SUBPKT_PREF_HASH_ALG 21
#define SUBPKT_PREF_COMPRESS_ALG 22
#define SUBPKT_KEY_SERVER_PREFS 23
#define SUBPKT_PREF_KEY_SERVER 24
#define SUBPKT_PRIMARY_USER_ID 25
#define SUBPKT_POLICY_URI 26
#define SUBPKT_KEY_FLAGS 27
#define SUBPKT_SIGNER_ID 28
#define SUBPKT_REVOCATION_REASON 29
#define SUBPKT_FEATURES 30
#define SUBPKT_SIGNATURE_TARGET 31
#define SUBPKT_EMBEDDED_SIGNATURE 32
#define UNCOMPRESSED 0
#define ZIP_COMPRESSION 1
#define ZLIB_COMPRESSION 2
#define BZIP2_COMPRESSION 3
/* get a 16 bit integer, in host order */
static uint16_t
get_16(uint8_t *p)
{
uint16_t u16;
memcpy(&u16, p, sizeof(u16));
return ntohs(u16);
}
/* get a 32 bit integer, in host order */
static uint32_t
get_32(uint8_t *p)
{
uint32_t u32;
memcpy(&u32, p, sizeof(u32));
return ntohl(u32);
}
#define HOURSECS (int64_t)(60 * 60)
#define DAYSECS (int64_t)(24 * 60 * 60)
#define MONSECS (int64_t)(30 * DAYSECS)
#define YEARSECS (int64_t)(365 * DAYSECS)
/* format (human readable) time into memory */
static size_t
fmt_time(char *s, size_t size, const char *header, int64_t n, const char *trailer, int relative)
{
struct tm tm;
time_t elapsed;
time_t now;
time_t t;
size_t cc;
t = (time_t)n;
now = time(NULL);
elapsed = now - t;
gmtime_r(&t, &tm);
cc = snprintf(s, size, "%s%04d-%02d-%02d", header,
tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday);
if (relative) {
cc += snprintf(&s[cc], size - cc, " (%lldy %lldm %lldd %lldh %s)",
llabs((long long)elapsed / YEARSECS),
llabs(((long long)elapsed % YEARSECS) / MONSECS),
llabs(((long long)elapsed % MONSECS) / DAYSECS),
llabs(((long long)elapsed % DAYSECS) / HOURSECS),
(now > t) ? "ago" : "ahead");
}
cc += snprintf(&s[cc], size - cc, "%s", trailer);
return cc;
}
/* dump key mpis to stdout */
static void
print_key_mpis(pgpv_bignum_t *v, uint8_t keyalg)
{
char s[8192];
switch(keyalg) {
case PUBKEY_RSA_ENCRYPT_OR_SIGN:
case PUBKEY_RSA_ENCRYPT:
case PUBKEY_RSA_SIGN:
fmt_mpi(s, sizeof(s), &v[RSA_N], "rsa.n", 1);
printf("%s", s);
fmt_mpi(s, sizeof(s), &v[RSA_E], "rsa.e", 1);
printf("%s", s);
break;
case PUBKEY_ELGAMAL_ENCRYPT:
fmt_mpi(s, sizeof(s), &v[ELGAMAL_P], "elgamal.p", 1);
printf("%s", s);
fmt_mpi(s, sizeof(s), &v[ELGAMAL_Y], "elgamal.y", 1);
printf("%s", s);
break;
case PUBKEY_DSA:
fmt_mpi(s, sizeof(s), &v[DSA_P], "dsa.p", 1);
printf("%s", s);
fmt_mpi(s, sizeof(s), &v[DSA_Q], "dsa.q", 1);
printf("%s", s);
fmt_mpi(s, sizeof(s), &v[DSA_G], "dsa.g", 1);
printf("%s", s);
fmt_mpi(s, sizeof(s), &v[DSA_Y], "dsa.y", 1);
printf("%s", s);
break;
default:
printf("hi, unusual keyalg %u\n", keyalg);
break;
}
}
/* get an mpi, including 2 byte length */
static int
get_mpi(pgpv_bignum_t *mpi, uint8_t *p, size_t pktlen, size_t *off)
{
size_t bytes;
mpi->bits = get_16(p);
if ((bytes = (size_t)BITS_TO_BYTES(mpi->bits)) > pktlen) {
return 0;
}
*off += sizeof(mpi->bits);
mpi->bn = BN_bin2bn(&p[sizeof(mpi->bits)], (int)bytes, NULL);
*off += bytes;
return 1;
}
/* read mpis in signature */
static int
read_signature_mpis(pgpv_sigpkt_t *sigpkt, uint8_t *p, size_t pktlen)
{
size_t off;
off = 0;
switch(sigpkt->sig.keyalg) {
case PUBKEY_RSA_ENCRYPT_OR_SIGN:
case PUBKEY_RSA_SIGN:
case PUBKEY_RSA_ENCRYPT:
if (!get_mpi(&sigpkt->sig.bn[RSA_SIG], p, pktlen, &off)) {
printf("sigpkt->version %d, rsa sig weird\n", sigpkt->sig.version);
return 0;
}
break;
case PUBKEY_DSA:
case PUBKEY_ECDSA:
case PUBKEY_ELGAMAL_ENCRYPT_OR_SIGN: /* deprecated */
if (!get_mpi(&sigpkt->sig.bn[DSA_R], p, pktlen, &off) ||
!get_mpi(&sigpkt->sig.bn[DSA_S], &p[off], pktlen, &off)) {
printf("sigpkt->version %d, dsa/elgamal sig weird\n", sigpkt->sig.version);
return 0;
}
break;
default:
printf("weird type of sig! %d\n", sigpkt->sig.keyalg);
return 0;
}
return 1;
}
/* add the signature sub packet to the signature packet */
static int
add_subpacket(pgpv_sigpkt_t *sigpkt, uint8_t tag, uint8_t *p, uint16_t len)
{
pgpv_sigsubpkt_t subpkt;
memset(&subpkt, 0x0, sizeof(subpkt));
subpkt.s.size = len;
subpkt.critical = 0;
subpkt.tag = tag;
subpkt.s.data = p;
ARRAY_APPEND(sigpkt->subpkts, subpkt);
return 1;
}
/* read the subpackets in the signature */
static int
read_sig_subpackets(pgpv_sigpkt_t *sigpkt, uint8_t *p, size_t pktlen)
{
pgpv_sigsubpkt_t subpkt;
const int is_subpkt = 0;
unsigned lenlen;
unsigned i;
uint8_t *start;
start = p;
for (i = 0 ; (unsigned)(p - start) < sigpkt->subslen ; i++) {
memset(&subpkt, 0x0, sizeof(subpkt));
subpkt.s.size = get_pkt_len(1, p, 0, is_subpkt);
lenlen = get_pkt_len_len(1, p, is_subpkt);
if (lenlen > pktlen) {
printf("weird lenlen %u\n", lenlen);
return 0;
}
p += lenlen;
subpkt.critical = (*p & SUBPKT_CRITICAL_MASK);
subpkt.tag = (*p & SUBPKT_TAG_MASK);
p += 1;
switch(subpkt.tag) {
case SUBPKT_SIG_BIRTH:
sigpkt->sig.birth = (int64_t)get_32(p);
break;
case SUBPKT_SIG_EXPIRY:
sigpkt->sig.expiry = (int64_t)get_32(p);
break;
case SUBPKT_KEY_EXPIRY:
sigpkt->sig.keyexpiry = (int64_t)get_32(p);
break;
case SUBPKT_ISSUER:
sigpkt->sig.signer = p;
break;
case SUBPKT_SIGNER_ID:
sigpkt->sig.signer = p;
break;
case SUBPKT_TRUST_SIG:
sigpkt->sig.trustsig = *p;
break;
case SUBPKT_REGEXP:
sigpkt->sig.regexp = (char *)(void *)p;
break;
case SUBPKT_REVOCABLE:
sigpkt->sig.revocable = *p;
break;
case SUBPKT_PREF_SYMMETRIC_ALG:
sigpkt->sig.pref_symm_alg = *p;
break;
case SUBPKT_REVOCATION_KEY:
sigpkt->sig.revoke_sensitive = (*p & 0x40);
sigpkt->sig.revoke_alg = p[1];
sigpkt->sig.revoke_fingerprint = &p[2];
break;
case SUBPKT_NOTATION:
sigpkt->sig.notation = *p;
break;
case SUBPKT_PREF_HASH_ALG:
sigpkt->sig.pref_hash_alg = *p;
break;
case SUBPKT_PREF_COMPRESS_ALG:
sigpkt->sig.pref_compress_alg = *p;
break;
case SUBPKT_PREF_KEY_SERVER:
sigpkt->sig.pref_key_server = (char *)(void *)p;
break;
case SUBPKT_KEY_SERVER_PREFS:
sigpkt->sig.key_server_modify = *p;
break;
case SUBPKT_KEY_FLAGS:
sigpkt->sig.type_key = *p;
break;
case SUBPKT_PRIMARY_USER_ID:
sigpkt->sig.primary_userid = *p;
break;
case SUBPKT_POLICY_URI:
sigpkt->sig.policy = (char *)(void *)p;
break;
case SUBPKT_FEATURES:
sigpkt->sig.features = (char *)(void *)p;
break;
case SUBPKT_REVOCATION_REASON:
sigpkt->sig.revoked = *p++ + 1;
sigpkt->sig.why_revoked = (char *)(void *)p;
break;
default:
printf("Ignoring unusual/reserved signature subpacket %d\n", subpkt.tag);
break;
}
subpkt.s.data = p;
p += subpkt.s.size - 1;
ARRAY_APPEND(sigpkt->subpkts, subpkt);
}
return 1;
}
/* parse signature packet */
static int
read_sigpkt(pgpv_t *pgp, uint8_t mement, pgpv_sigpkt_t *sigpkt, uint8_t *p, size_t pktlen)
{
unsigned lenlen;
uint8_t *base;
make_ref(pgp, mement, &sigpkt->sig.hashstart);
base = p;
switch(sigpkt->sig.version = *p++) {
case 2:
case 3:
if ((lenlen = *p++) != 5) {
printf("read_sigpkt: hashed length not 5\n");
return 0;
}
sigpkt->sig.hashlen = lenlen;
/* put birthtime into a subpacket */
sigpkt->sig.type = *p++;
add_subpacket(sigpkt, SUBPKT_SIG_BIRTH, p, sizeof(uint32_t));
sigpkt->sig.birth = (int64_t)get_32(p);
p += sizeof(uint32_t);
sigpkt->sig.signer = p;
add_subpacket(sigpkt, SUBPKT_SIGNER_ID, p, PGPV_KEYID_LEN);
p += PGPV_KEYID_LEN;
sigpkt->sig.keyalg = *p++;
sigpkt->sig.hashalg = *p++;
sigpkt->sig.hash2 = p;
if (!read_signature_mpis(sigpkt, sigpkt->sig.mpi = p + 2, pktlen)) {
printf("read_sigpkt: can't read sigs v3\n");
return 0;
}
break;
case 4:
sigpkt->sig.type = *p++;
sigpkt->sig.keyalg = *p++;
sigpkt->sig.hashalg = *p++;
sigpkt->subslen = get_16(p);
p += sizeof(sigpkt->subslen);
if (!read_sig_subpackets(sigpkt, p, pktlen)) {
printf("read_sigpkt: can't read sig subpackets, v4\n");
return 0;
}
if (!sigpkt->sig.signer) {
sigpkt->sig.signer = get_ref(&sigpkt->sig.hashstart) + 16;
}
p += sigpkt->subslen;
sigpkt->sig.hashlen = (unsigned)(p - base);
sigpkt->unhashlen = get_16(p);
p += sizeof(sigpkt->unhashlen) + sigpkt->unhashlen;
sigpkt->sig.hash2 = p;
if (!read_signature_mpis(sigpkt, sigpkt->sig.mpi = p + 2, pktlen)) {
printf("read_sigpkt: can't read sigs, v4\n");
return 0;
}
break;
default:
printf("read_sigpkt: unusual signature version (%u)\n", sigpkt->sig.version);
break;
}
return 1;
}
/* this parses compressed data, decompresses it, and calls the parser again */
static int
read_compressed(pgpv_t *pgp, pgpv_compress_t *compressed, uint8_t *p, size_t len)
{
pgpv_mem_t *unzmem;
bz_stream bz;
z_stream z;
int ok = 0;
compressed->compalg = *p;
compressed->s.size = len;
if ((compressed->s.data = calloc(1, len)) == NULL) {
printf("read_compressed: can't allocate %zu length\n", len);
return 0;
}
switch(compressed->compalg) {
case UNCOMPRESSED:
printf("not implemented %d compression yet\n", compressed->compalg);
return 0;
default:
break;
}
ARRAY_EXPAND(pgp->areas);
ARRAY_COUNT(pgp->areas) += 1;
unzmem = &ARRAY_LAST(pgp->areas);
unzmem->size = len * 10;
unzmem->dealloc = FREE_MEM;
if ((unzmem->mem = calloc(1, unzmem->size)) == NULL) {
printf("read_compressed: calloc failed!\n");
return 0;
}
switch(compressed->compalg) {
case ZIP_COMPRESSION:
case ZLIB_COMPRESSION:
memset(&z, 0x0, sizeof(z));
z.next_in = p + 1;
z.avail_in = (unsigned)(len - 1);
z.total_in = (unsigned)(len - 1);
z.next_out = unzmem->mem;
z.avail_out = (unsigned)unzmem->size;
z.total_out = (unsigned)unzmem->size;
break;
case BZIP2_COMPRESSION:
memset(&bz, 0x0, sizeof(bz));
bz.avail_in = (unsigned)(len - 1);
bz.next_in = (char *)(void *)p + 1;
bz.next_out = (char *)(void *)unzmem->mem;
bz.avail_out = (unsigned)unzmem->size;
break;
}
switch(compressed->compalg) {
case ZIP_COMPRESSION:
ok = (inflateInit2(&z, -15) == Z_OK);
break;
case ZLIB_COMPRESSION:
ok = (inflateInit(&z) == Z_OK);
break;
case BZIP2_COMPRESSION:
ok = (BZ2_bzDecompressInit(&bz, 1, 0) == BZ_OK);
break;
}
if (!ok) {
printf("read_compressed: initialisation failed!\n");
return 0;
}
switch(compressed->compalg) {
case ZIP_COMPRESSION:
case ZLIB_COMPRESSION:
ok = (inflate(&z, Z_FINISH) == Z_STREAM_END);
unzmem->size = z.total_out;
break;
case BZIP2_COMPRESSION:
ok = (BZ2_bzDecompress(&bz) == BZ_STREAM_END);
unzmem->size = ((uint64_t)bz.total_out_hi32 << 32) | bz.total_out_lo32;
break;
}
if (!ok) {
printf("read_compressed: inflate failed!\n");
return 0;
}
return 1;
}
/* parse one pass signature packet */
static int
read_onepass_sig(pgpv_onepass_t *onepasspkt, uint8_t *mem)
{
onepasspkt->version = mem[0];
onepasspkt->type = mem[1];
onepasspkt->hashalg = mem[2];
onepasspkt->keyalg = mem[3];
memcpy(onepasspkt->keyid, &mem[4], sizeof(onepasspkt->keyid));
onepasspkt->nested = mem[12];
return 1;
}
/* parse public key packet */
static int
read_pubkey(pgpv_pubkey_t *pubkey, uint8_t *mem, size_t pktlen, int pbn)
{
size_t off;
off = 0;
pubkey->version = mem[off++];
pubkey->birth = get_32(&mem[off]);
off += 4;
if (pubkey->version == 2 || pubkey->version == 3) {
pubkey->expiry = get_16(&mem[off]) * DAYSECS;
off += 2;
}
if ((pubkey->keyalg = mem[off++]) == 0) {
pubkey->keyalg = PUBKEY_RSA_ENCRYPT_OR_SIGN;
printf("got unusual pubkey keyalg %u\n", mem[off - 1]);
}
switch(pubkey->keyalg) {
case PUBKEY_RSA_ENCRYPT_OR_SIGN:
case PUBKEY_RSA_ENCRYPT:
case PUBKEY_RSA_SIGN:
if (!get_mpi(&pubkey->bn[RSA_N], &mem[off], pktlen, &off) ||
!get_mpi(&pubkey->bn[RSA_E], &mem[off], pktlen, &off)) {
return 0;
}
break;
case PUBKEY_ELGAMAL_ENCRYPT:
case PUBKEY_ELGAMAL_ENCRYPT_OR_SIGN:
if (!get_mpi(&pubkey->bn[ELGAMAL_P], &mem[off], pktlen, &off) ||
!get_mpi(&pubkey->bn[ELGAMAL_Y], &mem[off], pktlen, &off)) {
return 0;
}
break;
case PUBKEY_DSA:
if (!get_mpi(&pubkey->bn[DSA_P], &mem[off], pktlen, &off) ||
!get_mpi(&pubkey->bn[DSA_Q], &mem[off], pktlen, &off) ||
!get_mpi(&pubkey->bn[DSA_G], &mem[off], pktlen, &off) ||
!get_mpi(&pubkey->bn[DSA_Y], &mem[off], pktlen, &off)) {
return 0;
}
break;
default:
printf("hi, different type of pubkey here %u\n", pubkey->keyalg);
break;
}
if (pbn) {
print_key_mpis(pubkey->bn, pubkey->keyalg);
}
return 1;
}
/* parse a user attribute */
static int
read_userattr(pgpv_userattr_t *userattr, uint8_t *p, size_t pktlen)
{
pgpv_string_t subattr;
const int is_subpkt = 0;
const int indian = 1;
unsigned lenlen;
uint16_t imagelen;
size_t cc;
userattr->len = pktlen;
for (cc = 0 ; cc < pktlen ; cc += subattr.size + lenlen + 1) {
subattr.size = get_pkt_len(1, p, 0, is_subpkt);
lenlen = get_pkt_len_len(1, p, is_subpkt);
if (lenlen > pktlen) {
printf("weird lenlen %u\n", lenlen);
return 0;
}
p += lenlen;
if (*p++ != 1) {
printf("image type (%u) != 1. weird packet\n", *(p - 1));
}
memcpy(&imagelen, p, sizeof(imagelen));
if (!*(const char *)(const void *)&indian) {
/* big endian - byteswap length */
imagelen = (((unsigned)imagelen & 0xff) << 8) | (((unsigned)imagelen >> 8) & 0xff);
}
subattr.data = p + 3;
p += subattr.size;
ARRAY_APPEND(userattr->subattrs, subattr);
}
return 1;
}
#define LITDATA_BINARY 'b'
#define LITDATA_TEXT 't'
#define LITDATA_UTF8 'u'
/* parse literal packet */
static int
read_litdata(pgpv_t *pgp, pgpv_litdata_t *litdata, uint8_t *p, size_t size)
{
size_t cc;
cc = 0;
switch(litdata->format = p[cc++]) {
case LITDATA_BINARY:
case LITDATA_TEXT:
case LITDATA_UTF8:
litdata->namelen = 0;
break;
default:
printf("weird litdata format %u\n", litdata->format);
break;
}
litdata->namelen = p[cc++];
litdata->filename = &p[cc];
cc += litdata->namelen;
litdata->secs = get_32(&p[cc]);
cc += 4;
litdata->s.data = &p[cc];
litdata->len = litdata->s.size = size - cc;
litdata->mem = ARRAY_COUNT(pgp->areas) - 1;
litdata->offset = cc;
return 1;
}
/* parse a single packet */
static int
read_pkt(pgpv_t *pgp, pgpv_mem_t *mem)
{
const int isprimary = 1;
pgpv_pkt_t pkt;
pgpv_mem_t *newmem;
unsigned lenlen;
uint8_t ispartial;
size_t size;
memset(&pkt, 0x0, sizeof(pkt));
pkt.tag = mem->mem[mem->cc++];
if (!(pkt.tag & PKT_ALWAYS_ON)) {
printf("BAD PACKET - bit 7 not 1, offset %zu!\n", mem->cc - 1);
}
pkt.newfmt = (pkt.tag & PKT_NEWFMT_MASK);
pkt.tag = (pkt.newfmt) ?
(pkt.tag & PKT_NEWFMT_TAG_MASK) :
(((unsigned)pkt.tag & PKT_OLDFMT_TAG_MASK) >> 2);
ispartial = (pkt.newfmt && IS_PARTIAL(mem->mem[mem->cc]));
pkt.s.size = get_pkt_len(pkt.newfmt, &mem->mem[mem->cc], mem->size - mem->cc, isprimary);
lenlen = get_pkt_len_len(pkt.newfmt, &mem->mem[mem->cc], isprimary);
pkt.offset = mem->cc;
mem->cc += lenlen;
pkt.mement = (uint8_t)(mem - ARRAY_ARRAY(pgp->areas));
pkt.s.data = &mem->mem[mem->cc];
if (strchr(mem->allowed, pkt.tag) == NULL) {
printf("packet %d not allowed for operation %s\n", pkt.tag, pgp->op);
return 0;
}
size = pkt.s.size;
if (ispartial) {
pkt.s.size = fixup_partials(pgp, &mem->mem[mem->cc - lenlen], pkt.s.size, mem->size, &size);
newmem = &ARRAY_LAST(pgp->areas);
pkt.mement = (uint8_t)(newmem - ARRAY_ARRAY(pgp->areas));
pkt.s.data = newmem->mem;
size -= 1;
}
switch(pkt.tag) {
case SIGNATURE_PKT:
if (!read_sigpkt(pgp, pkt.mement, &pkt.u.sigpkt, pkt.s.data, pkt.s.size)) {
return 0;
}
break;
case ONEPASS_SIGNATURE_PKT:
read_onepass_sig(&pkt.u.onepass, pkt.s.data);
break;
case PUBKEY_PKT:
case PUB_SUBKEY_PKT:
break;
case LITDATA_PKT:
read_litdata(pgp, &pkt.u.litdata, pkt.s.data, pkt.s.size);
break;
case TRUST_PKT:
pkt.u.trust.level = pkt.s.data[0];
pkt.u.trust.amount = pkt.s.data[1];
break;
case USERID_PKT:
pkt.u.userid.size = pkt.s.size;
pkt.u.userid.data = pkt.s.data;
break;
case COMPRESSED_DATA_PKT:
read_compressed(pgp, &pkt.u.compressed, pkt.s.data, pkt.s.size);
ARRAY_APPEND(pgp->pkts, pkt);
read_all_packets(pgp, &ARRAY_LAST(pgp->areas), pgp->op);
break;
case USER_ATTRIBUTE_PKT:
read_userattr(&pkt.u.userattr, pkt.s.data, pkt.s.size);
break;
default:
printf("hi, need to implement %d, offset %zu\n", pkt.tag, mem->cc);
break;
}
mem->cc += size;
if (pkt.tag != COMPRESSED_DATA_PKT) {
/* compressed was added earlier to preserve pkt ordering */
ARRAY_APPEND(pgp->pkts, pkt);
}
return 1;
}
/* checks the tag type of a packet */
static int
pkt_is(pgpv_t *pgp, int wanted)
{
return (ARRAY_ELEMENT(pgp->pkts, pgp->pkt).tag == wanted);
}
/* checks the packet is a signature packet, and the signature type is the expected one */
static int
pkt_sigtype_is(pgpv_t *pgp, int wanted)
{
if (!pkt_is(pgp, SIGNATURE_PKT)) {
return 0;
}
return (ARRAY_ELEMENT(pgp->pkts, pgp->pkt).u.sigpkt.sig.type == wanted);
}
/* check for expected type of packet, and move to the next */
static int
pkt_accept(pgpv_t *pgp, int expected)
{
int got;
if ((got = ARRAY_ELEMENT(pgp->pkts, pgp->pkt).tag) == expected) {
pgp->pkt += 1;
return 1;
}
printf("problem at token %zu, expcted %d, got %d\n", pgp->pkt, expected, got);
return 0;
}
/* recognise signature (and trust) packet */
static int
recog_signature(pgpv_t *pgp, pgpv_signature_t *signature)
{
if (!pkt_is(pgp, SIGNATURE_PKT)) {
printf("recog_signature: not a signature packet\n");
return 0;
}
memcpy(signature, &ARRAY_ELEMENT(pgp->pkts, pgp->pkt).u.sigpkt.sig, sizeof(*signature));
pgp->pkt += 1;
if (pkt_is(pgp, TRUST_PKT)) {
pkt_accept(pgp, TRUST_PKT);
}
return 1;
}
/* recognise user id packet */
static int
recog_userid(pgpv_t *pgp, pgpv_signed_userid_t *userid)
{
pgpv_signature_t signature;
pgpv_pkt_t *pkt;
memset(userid, 0x0, sizeof(*userid));
if (!pkt_is(pgp, USERID_PKT)) {
printf("recog_userid: not %d\n", USERID_PKT);
return 0;
}
pkt = &ARRAY_ELEMENT(pgp->pkts, pgp->pkt);
userid->userid.size = pkt->s.size;
userid->userid.data = pkt->s.data;
pgp->pkt += 1;
while (pkt_is(pgp, SIGNATURE_PKT)) {
if (!recog_signature(pgp, &signature)) {
printf("recog_userid: can't recognise signature/trust\n");
return 0;
}
ARRAY_APPEND(userid->sigs, signature);
if (signature.primary_userid) {
userid->primary_userid = signature.primary_userid;
}
if (signature.revoked) {
userid->revoked = signature.revoked;
}
}
return 1;
}
/* recognise user attributes packet */
static int
recog_userattr(pgpv_t *pgp, pgpv_signed_userattr_t *userattr)
{
pgpv_signature_t signature;
memset(userattr, 0x0, sizeof(*userattr));
if (!pkt_is(pgp, USER_ATTRIBUTE_PKT)) {
printf("recog_userattr: not %d\n", USER_ATTRIBUTE_PKT);
return 0;
}
userattr->userattr = ARRAY_ELEMENT(pgp->pkts, pgp->pkt).u.userattr;
pgp->pkt += 1;
while (pkt_is(pgp, SIGNATURE_PKT)) {
if (!recog_signature(pgp, &signature)) {
printf("recog_userattr: can't recognise signature/trust\n");
return 0;
}
ARRAY_APPEND(userattr->sigs, signature);
if (signature.revoked) {
userattr->revoked = signature.revoked;
}
}
return 1;
}
/* recognise a sub key */
static int
recog_subkey(pgpv_t *pgp, pgpv_signed_subkey_t *subkey)
{
pgpv_signature_t signature;
pgpv_pkt_t *pkt;
pkt = &ARRAY_ELEMENT(pgp->pkts, pgp->pkt);
memset(subkey, 0x0, sizeof(*subkey));
read_pubkey(&subkey->subkey, pkt->s.data, pkt->s.size, 0);
pgp->pkt += 1;
if (pkt_sigtype_is(pgp, SIGTYPE_KEY_REVOCATION) ||
pkt_sigtype_is(pgp, SIGTYPE_SUBKEY_REVOCATION) ||
pkt_sigtype_is(pgp, SIGTYPE_CERT_REVOCATION)) {
recog_signature(pgp, &signature);
subkey->revoc_self_sig = signature;
}
do {
if (!pkt_is(pgp, SIGNATURE_PKT)) {
printf("recog_subkey: not signature packet at %zu\n", pgp->pkt);
return 0;
}
if (!recog_signature(pgp, &signature)) {
printf("recog_subkey: bad signature/trust at %zu\n", pgp->pkt);
return 0;
}
ARRAY_APPEND(subkey->sigs, signature);
if (signature.keyexpiry) {
/* XXX - check it's a good key expiry */
subkey->subkey.expiry = signature.keyexpiry;
}
} while (pkt_is(pgp, SIGNATURE_PKT));
return 1;
}
/* use a sparse map for the text strings here to save space */
static const char *keyalgs[] = {
"[Unknown]",
"RSA (Encrypt or Sign)",
"RSA (Encrypt Only)",
"RSA (Sign Only)",
"Elgamal (Encrypt Only)",
"DSA",
"Elliptic Curve",
"ECDSA",
"Elgamal (Encrypt or Sign)"
};
#define MAX_KEYALG 21
static const char *keyalgmap = "\0\01\02\03\0\0\0\0\0\0\0\0\0\0\0\0\04\05\06\07\010\011";
/* return human readable name for key algorithm */
static const char *
fmtkeyalg(uint8_t keyalg)
{
return keyalgs[(uint8_t)keyalgmap[(keyalg >= MAX_KEYALG) ? 0 : keyalg]];
}
/* return the number of bits in the public key */
static unsigned
numkeybits(const pgpv_pubkey_t *pubkey)
{
switch(pubkey->keyalg) {
case PUBKEY_RSA_ENCRYPT_OR_SIGN:
case PUBKEY_RSA_ENCRYPT:
case PUBKEY_RSA_SIGN:
return pubkey->bn[RSA_N].bits;
case PUBKEY_DSA:
case PUBKEY_ECDSA:
return BITS_TO_BYTES(pubkey->bn[DSA_Q].bits) * 64;
case PUBKEY_ELGAMAL_ENCRYPT:
case PUBKEY_ELGAMAL_ENCRYPT_OR_SIGN:
return pubkey->bn[ELGAMAL_P].bits;
default:
return 0;
}
}
/* print a public key */
static size_t
fmt_pubkey(char *s, size_t size, pgpv_pubkey_t *pubkey, const char *leader)
{
size_t cc;
cc = snprintf(s, size, "%s %u/%s ", leader, numkeybits(pubkey), fmtkeyalg(pubkey->keyalg));
cc += fmt_binary(&s[cc], size - cc, pubkey->keyid, PGPV_KEYID_LEN);
cc += fmt_time(&s[cc], size - cc, " ", pubkey->birth, "", 0);
if (pubkey->expiry) {
cc += fmt_time(&s[cc], size - cc, " [Expiry ", pubkey->birth + pubkey->expiry, "]", 0);
}
cc += snprintf(&s[cc], size - cc, "\n");
cc += fmt_fingerprint(&s[cc], size - cc, &pubkey->fingerprint, "fingerprint: ");
return cc;
}
/* we add 1 to revocation value to denote compromised */
#define COMPROMISED (0x02 + 1)
/* format a userid - used to order the userids when formatting */
static size_t
fmt_userid(char *s, size_t size, pgpv_primarykey_t *primary, uint8_t u)
{
pgpv_signed_userid_t *userid;
userid = &ARRAY_ELEMENT(primary->signed_userids, u);
return snprintf(s, size, "uid %.*s%s\n",
(int)userid->userid.size, userid->userid.data,
(userid->revoked == COMPROMISED) ? " [COMPROMISED AND REVOKED]" :
(userid->revoked) ? " [REVOKED]" : "");
}
/* print a primary key, per RFC 4880 */
static size_t
fmt_primary(char *s, size_t size, pgpv_primarykey_t *primary)
{
unsigned i;
size_t cc;
cc = fmt_pubkey(s, size, &primary->primary, "signature ");
cc += fmt_userid(&s[cc], size - cc, primary, primary->primary_userid);
for (i = 0 ; i < ARRAY_COUNT(primary->signed_userids) ; i++) {
if (i != primary->primary_userid) {
cc += fmt_userid(&s[cc], size - cc, primary, i);
}
}
for (i = 0 ; i < ARRAY_COUNT(primary->signed_subkeys) ; i++) {
cc += fmt_pubkey(&s[cc], size - cc, &ARRAY_ELEMENT(primary->signed_subkeys, i).subkey, "encryption");
}
cc += snprintf(&s[cc], size - cc, "\n");
return cc;
}
/* check the padding on the signature */
static int
rsa_padding_check_none(uint8_t *to, int tlen, const uint8_t *from, int flen, int num)
{
USE_ARG(num);
if (flen > tlen) {
printf("from length larger than to length\n");
return -1;
}
(void) memset(to, 0x0, tlen - flen);
(void) memcpy(to + tlen - flen, from, flen);
return tlen;
}
#define RSA_MAX_MODULUS_BITS 16384
#define RSA_SMALL_MODULUS_BITS 3072
#define RSA_MAX_PUBEXP_BITS 64 /* exponent limit enforced for "large" modulus only */
/* check against the exponent/moudulo operation */
static int
lowlevel_rsa_public_check(const uint8_t *encbuf, int enclen, uint8_t *dec, const rsa_pubkey_t *rsa)
{
uint8_t *decbuf;
BIGNUM *decbn;
BIGNUM *encbn;
int decbytes;
int nbytes;
int r;
nbytes = 0;
r = -1;
decbuf = NULL;
decbn = encbn = NULL;
if (BN_num_bits(rsa->n) > RSA_MAX_MODULUS_BITS) {
printf("rsa r modulus too large\n");
goto err;
}
if (BN_cmp(rsa->n, rsa->e) <= 0) {
printf("rsa r bad n value\n");
goto err;
}
if (BN_num_bits(rsa->n) > RSA_SMALL_MODULUS_BITS &&
BN_num_bits(rsa->e) > RSA_MAX_PUBEXP_BITS) {
printf("rsa r bad exponent limit\n");
goto err;
}
if ((encbn = BN_new()) == NULL ||
(decbn = BN_new()) == NULL ||
(decbuf = calloc(1, nbytes = BN_num_bytes(rsa->n))) == NULL) {
printf("allocation failure\n");
goto err;
}
if (enclen > nbytes) {
printf("rsa r > mod len\n");
goto err;
}
if (BN_bin2bn(encbuf, enclen, encbn) == NULL) {
printf("null encrypted BN\n");
goto err;
}
if (BN_cmp(encbn, rsa->n) >= 0) {
printf("rsa r data too large for modulus\n");
goto err;
}
if (BN_mod_exp(decbn, encbn, rsa->e, rsa->n, NULL) < 0) {
printf("BN_mod_exp < 0\n");
goto err;
}
decbytes = BN_num_bytes(decbn);
(void) BN_bn2bin(decbn, decbuf);
if ((r = rsa_padding_check_none(dec, nbytes, decbuf, decbytes, 0)) < 0) {
printf("rsa r padding check failed\n");
}
err:
BN_free(encbn);
BN_free(decbn);
if (decbuf != NULL) {
(void) memset(decbuf, 0x0, nbytes);
free(decbuf);
}
return r;
}
/* verify */
static int
rsa_public_decrypt(int enclen, const unsigned char *enc, unsigned char *dec, RSA *rsa, int padding)
{
rsa_pubkey_t pub;
int ret;
if (enc == NULL || dec == NULL || rsa == NULL) {
return 0;
}
USE_ARG(padding);
(void) memset(&pub, 0x0, sizeof(pub));
pub.n = BN_dup(rsa->n);
pub.e = BN_dup(rsa->e);
ret = lowlevel_rsa_public_check(enc, enclen, dec, &pub);
BN_free(pub.n);
BN_free(pub.e);
return ret;
}
#define SUBKEY_LEN(x) (80 + 80)
#define SIG_LEN 80
#define UID_LEN 80
/* return worst case number of bytes needed to format a primary key */
static size_t
estimate_primarykey_size(pgpv_primarykey_t *primary)
{
size_t cc;
cc = SUBKEY_LEN("signature") +
(ARRAY_COUNT(primary->signed_userids) * UID_LEN) +
(ARRAY_COUNT(primary->signed_subkeys) * SUBKEY_LEN("encrypt uids"));
return cc;
}
/* use public decrypt to verify a signature */
static int
pgpv_rsa_public_decrypt(uint8_t *out, const uint8_t *in, size_t length, const pgpv_pubkey_t *pubkey)
{
RSA *orsa;
int n;
if ((orsa = calloc(1, sizeof(*orsa))) == NULL) {
return 0;
}
orsa->n = pubkey->bn[RSA_N].bn;
orsa->e = pubkey->bn[RSA_E].bn;
n = rsa_public_decrypt((int)length, in, out, orsa, RSA_NO_PADDING);
orsa->n = orsa->e = NULL;
free(orsa);
return n;
}
/* verify rsa signature */
static int
rsa_verify(uint8_t *calculated, unsigned calclen, uint8_t hashalg, pgpv_bignum_t *bn, pgpv_pubkey_t *pubkey)
{
unsigned prefixlen;
unsigned decryptc;
unsigned i;
uint8_t decrypted[8192];
uint8_t sigbn[8192];
uint8_t prefix[64];
size_t keysize;
keysize = BITS_TO_BYTES(pubkey->bn[RSA_N].bits);
BN_bn2bin(bn[RSA_SIG].bn, sigbn);
decryptc = pgpv_rsa_public_decrypt(decrypted, sigbn, BITS_TO_BYTES(bn[RSA_SIG].bits), pubkey);
if (decryptc != keysize || (decrypted[0] != 0 || decrypted[1] != 1)) {
return 0;
}
if ((prefixlen = digest_get_prefix((unsigned)hashalg, prefix, sizeof(prefix))) == 0) {
printf("rsa_verify: unknown hash algorithm: %d\n", hashalg);
return 0;
}
for (i = 2 ; i < keysize - prefixlen - calclen - 1 ; i++) {
if (decrypted[i] != 0xff) {
return 0;
}
}
if (decrypted[i++] != 0x0) {
return 0;
}
if (memcmp(&decrypted[i], prefix, prefixlen) != 0) {
printf("rsa_verify: wrong hash algorithm\n");
return 0;
}
return memcmp(&decrypted[i + prefixlen], calculated, calclen) == 0;
}
/* return 1 if bn <= 0 */
static int
bignum_is_bad(BIGNUM *bn)
{
return BN_is_zero(bn) || BN_is_negative(bn);
}
#define BAD_BIGNUM(s, k) \
(bignum_is_bad((s)->bn) || BN_cmp((s)->bn, (k)->bn) >= 0)
#ifndef DSA_MAX_MODULUS_BITS
#define DSA_MAX_MODULUS_BITS 10000
#endif
/* verify DSA signature */
static int
verify_dsa_sig(uint8_t *calculated, unsigned calclen, pgpv_bignum_t *sig, pgpv_pubkey_t *pubkey)
{
unsigned qbits;
uint8_t calcnum[128];
uint8_t signum[128];
BIGNUM *M;
BIGNUM *W;
BIGNUM *t1;
int ret;
if (pubkey->bn[DSA_P].bn == NULL ||
pubkey->bn[DSA_Q].bn == NULL ||
pubkey->bn[DSA_G].bn == NULL) {
return 0;
}
M = W = t1 = NULL;
qbits = pubkey->bn[DSA_Q].bits;
switch(qbits) {
case 160:
case 224:
case 256:
break;
default:
printf("dsa: bad # of Q bits\n");
return 0;
}
if (pubkey->bn[DSA_P].bits > DSA_MAX_MODULUS_BITS) {
printf("dsa: p too large\n");
return 0;
}
if (calclen > SHA256_DIGEST_LENGTH) {
printf("dsa: digest too long\n");
return 0;
}
ret = 0;
if ((M = BN_new()) == NULL || (W = BN_new()) == NULL || (t1 = BN_new()) == NULL ||
BAD_BIGNUM(&sig[DSA_R], &pubkey->bn[DSA_Q]) ||
BAD_BIGNUM(&sig[DSA_S], &pubkey->bn[DSA_Q]) ||
BN_mod_inverse(W, sig[DSA_S].bn, pubkey->bn[DSA_Q].bn, NULL) == NULL) {
goto done;
}
if (calclen > qbits / 8) {
calclen = qbits / 8;
}
if (BN_bin2bn(calculated, (int)calclen, M) == NULL ||
!BN_mod_mul(M, M, W, pubkey->bn[DSA_Q].bn, NULL) ||
!BN_mod_mul(W, sig[DSA_R].bn, W, pubkey->bn[DSA_Q].bn, NULL) ||
!BN_mod_exp(t1, pubkey->bn[DSA_G].bn, M, pubkey->bn[DSA_P].bn, NULL) ||
!BN_mod_exp(W, pubkey->bn[DSA_Y].bn, W, pubkey->bn[DSA_P].bn, NULL) ||
!BN_mod_mul(t1, t1, W, pubkey->bn[DSA_P].bn, NULL) ||
!BN_div(NULL, t1, t1, pubkey->bn[DSA_Q].bn, NULL)) {
goto done;
}
/* only compare the first q bits */
BN_bn2bin(t1, calcnum);
BN_bn2bin(sig[DSA_R].bn, signum);
ret = memcmp(calcnum, signum, BITS_TO_BYTES(qbits)) == 0;
done:
if (M) {
BN_free(M);
}
if (W) {
BN_free(W);
}
if (t1) {
BN_free(t1);
}
return ret;
}
#define TIME_SNPRINTF(_cc, _buf, _size, _fmt, _val) do { \
time_t _t; \
char *_s; \
\
_t = _val; \
_s = ctime(&_t); \
_cc += snprintf(_buf, _size, _fmt, _s); \
} while(/*CONSTCOND*/0)
/* check dates on signature and key are valid */
static size_t
valid_dates(pgpv_signature_t *signature, pgpv_pubkey_t *pubkey, char *buf, size_t size)
{
time_t now;
time_t t;
size_t cc;
cc = 0;
if (signature->birth < pubkey->birth) {
TIME_SNPRINTF(cc, buf, size, "Signature time (%.24s) was before pubkey creation ", signature->birth);
TIME_SNPRINTF(cc, &buf[cc], size - cc, "(%s)\n", pubkey->birth);
return cc;
}
now = time(NULL);
if (signature->expiry != 0) {
if ((t = signature->birth + signature->expiry) < now) {
TIME_SNPRINTF(cc, buf, size, "Signature expired on %.24s\n", t);
return cc;
}
}
if (now < signature->birth) {
TIME_SNPRINTF(cc, buf, size, "Signature not valid before %.24s\n", signature->birth);
return cc;
}
return 0;
}
/* check if the signing key has expired */
static int
key_expired(pgpv_pubkey_t *pubkey, char *buf, size_t size)
{
time_t now;
time_t t;
size_t cc;
now = time(NULL);
cc = 0;
if (pubkey->expiry != 0) {
if ((t = pubkey->birth + pubkey->expiry) < now) {
TIME_SNPRINTF(cc, buf, size, "Pubkey expired on %.24s\n", t);
return (int)cc;
}
}
if (now < pubkey->birth) {
TIME_SNPRINTF(cc, buf, size, "Pubkey not valid before %.24s\n", pubkey->birth);
return (int)cc;
}
return 0;
}
/* find the leading onepass packet */
static size_t
find_onepass(pgpv_cursor_t *cursor, size_t datastart)
{
size_t pkt;
for (pkt = datastart ; pkt < ARRAY_COUNT(cursor->pgp->pkts) ; pkt++) {
if (ARRAY_ELEMENT(cursor->pgp->pkts, pkt).tag == ONEPASS_SIGNATURE_PKT) {
return pkt + 1;
}
}
snprintf(cursor->why, sizeof(cursor->why), "No signature to verify");
return 0;
}
static const char *armor_begins[] = {
"-----BEGIN PGP SIGNED MESSAGE-----\n",
"-----BEGIN PGP MESSAGE-----\n",
NULL
};
/* return non-zero if the buf introduces an armored message */
static int
is_armored(const char *buf, size_t size)
{
const char **arm;
const char *nl;
size_t n;
if ((nl = memchr(buf, '\n', size)) == NULL) {
return 0;
}
n = (size_t)(nl - buf);
for (arm = armor_begins ; *arm ; arm++) {
if (strncmp(buf, *arm, n) == 0) {
return 1;
}
}
return 0;
}
#define SIGSTART "-----BEGIN PGP SIGNATURE-----\n"
#define SIGEND "-----END PGP SIGNATURE-----\n"
/* for ascii armor, we don't get a onepass packet - make one */
static const char *cons_onepass = "\304\015\003\0\0\0\0\377\377\377\377\377\377\377\377\1";
/* read ascii armor */
static int
read_ascii_armor(pgpv_cursor_t *cursor, pgpv_mem_t *mem, const char *filename)
{
pgpv_onepass_t *onepass;
pgpv_sigpkt_t *sigpkt;
pgpv_pkt_t litdata;
uint8_t binsig[8192];
uint8_t *datastart;
uint8_t *sigend;
uint8_t *p;
size_t binsigsize;
/* cons up litdata pkt */
memset(&litdata, 0x0, sizeof(litdata));
litdata.u.litdata.mem = ARRAY_COUNT(cursor->pgp->areas) - 1;
p = mem->mem;
/* jump over signed message line */
if ((p = memmem(mem->mem, mem->size, "\n\n", 2)) == NULL) {
snprintf(cursor->why, sizeof(cursor->why), "malformed armor at offset 0");
return 0;
}
p += 2;
litdata.tag = LITDATA_PKT;
litdata.s.data = p;
litdata.u.litdata.offset = (size_t)(p - mem->mem);
litdata.u.litdata.filename = (uint8_t *)strdup(filename);
if ((p = memmem(datastart = p, mem->size - litdata.offset, SIGSTART, strlen(SIGSTART))) == NULL) {
snprintf(cursor->why, sizeof(cursor->why),
"malformed armor - no sig - at %zu", (size_t)(p - mem->mem));
return 0;
}
litdata.u.litdata.len = litdata.s.size = (size_t)(p - datastart);
p += strlen(SIGSTART);
if ((p = memmem(p, mem->size, "\n\n", 2)) == NULL) {
snprintf(cursor->why, sizeof(cursor->why),
"malformed armed signature at %zu", (size_t)(p - mem->mem));
return 0;
}
p += 2;
sigend = memmem(p, mem->size, SIGEND, strlen(SIGEND));
binsigsize = b64decode((char *)p, (size_t)(sigend - p), binsig, sizeof(binsig));
read_binary_memory(cursor->pgp, "signature", cons_onepass, 15);
ARRAY_APPEND(cursor->pgp->pkts, litdata);
read_binary_memory(cursor->pgp, "signature", binsig, binsigsize - 3);
/* XXX - hardwired - 3 is format and length */
/* fix up packets in the packet array now we have them there */
onepass = &ARRAY_ELEMENT(cursor->pgp->pkts, ARRAY_COUNT(cursor->pgp->pkts) - 1 - 2).u.onepass;
sigpkt = &ARRAY_LAST(cursor->pgp->pkts).u.sigpkt;
memcpy(onepass->keyid, sigpkt->sig.signer, sizeof(onepass->keyid));
onepass->hashalg = sigpkt->sig.hashalg;
onepass->keyalg = sigpkt->sig.keyalg;
return 1;
}
/* read ascii armor from a file */
static int
read_ascii_armor_file(pgpv_cursor_t *cursor, const char *filename)
{
/* cons up litdata pkt */
read_file(cursor->pgp, filename);
return read_ascii_armor(cursor, &ARRAY_LAST(cursor->pgp->areas), filename);
}
/* read ascii armor from memory */
static int
read_ascii_armor_memory(pgpv_cursor_t *cursor, const void *p, size_t size)
{
pgpv_mem_t *mem;
/* cons up litdata pkt */
ARRAY_EXPAND(cursor->pgp->areas);
ARRAY_COUNT(cursor->pgp->areas) += 1;
mem = &ARRAY_LAST(cursor->pgp->areas);
memset(mem, 0x0, sizeof(*mem));
mem->size = size;
mem->mem = __UNCONST(p);
mem->dealloc = 0;
return read_ascii_armor(cursor, mem, "[stdin]");
}
/* set up the data to verify */
static int
setup_data(pgpv_cursor_t *cursor, pgpv_t *pgp, const void *p, ssize_t size)
{
FILE *fp;
char buf[BUFSIZ];
if (cursor == NULL || pgp == NULL || p == NULL) {
return 0;
}
memset(cursor, 0x0, sizeof(*cursor));
ARRAY_APPEND(pgp->datastarts, pgp->pkt);
cursor->pgp = pgp;
if (size < 0) {
/* we have a file name in p */
if ((fp = fopen(p, "r")) == NULL) {
snprintf(cursor->why, sizeof(cursor->why), "No such file '%s'", (const char *)p);
return 0;
}
if (fgets(buf, (int)sizeof(buf), fp) == NULL) {
fclose(fp);
snprintf(cursor->why, sizeof(cursor->why), "can't read file '%s'", (const char *)p);
return 0;
}
if (is_armored(buf, sizeof(buf))) {
read_ascii_armor_file(cursor, p);
} else {
read_binary_file(pgp, "signature", "%s", (const char *)p);
}
fclose(fp);
} else {
if (is_armored(p, (size_t)size)) {
read_ascii_armor_memory(cursor, p, (size_t)size);
} else {
read_binary_memory(pgp, "signature", p, (size_t)size);
}
}
return 1;
}
/* get the data and size from litdata packet */
static uint8_t *
get_literal_data(pgpv_cursor_t *cursor, pgpv_litdata_t *litdata, size_t *size)
{
pgpv_mem_t *mem;
if (litdata->s.data == NULL && litdata->s.size == 0) {
mem = &ARRAY_ELEMENT(cursor->pgp->areas, litdata->mem);
*size = litdata->len;
return &mem->mem[litdata->offset];
}
*size = litdata->s.size;
return litdata->s.data;
}
/*
RFC 4880 describes the structure of v4 keys as:
Primary-Key
[Revocation Self Signature]
[Direct Key Signature...]
User ID [Signature ...]
[User ID [Signature ...] ...]
[User Attribute [Signature ...] ...]
[[Subkey [Binding-Signature-Revocation]
Primary-Key-Binding-Signature] ...]
and that's implemented below as a recursive descent parser.
It has had to be modified, though: see the comment
some keys out there have user ids where they shouldn't
to look like:
Primary-Key
[Revocation Self Signature]
[Direct Key Signature...]
[User ID [Signature ...]
[User ID [Signature ...] ...]
[User Attribute [Signature ...] ...]
[Subkey [Binding-Signature-Revocation]
Primary-Key-Binding-Signature] ...]
to accommodate keyrings set up by gpg
*/
/* recognise a primary key */
static int
recog_primary_key(pgpv_t *pgp, pgpv_primarykey_t *primary)
{
pgpv_signed_userattr_t userattr;
pgpv_signed_userid_t userid;
pgpv_signed_subkey_t subkey;
pgpv_signature_t signature;
pgpv_pkt_t *pkt;
pkt = &ARRAY_ELEMENT(pgp->pkts, pgp->pkt);
memset(primary, 0x0, sizeof(*primary));
read_pubkey(&primary->primary, pkt->s.data, pkt->s.size, 0);
pgp->pkt += 1;
if (pkt_sigtype_is(pgp, SIGTYPE_KEY_REVOCATION)) {
if (!recog_signature(pgp, &primary->revoc_self_sig)) {
printf("recog_primary_key: no signature/trust at PGPV_SIGTYPE_KEY_REVOCATION\n");
return 0;
}
}
while (pkt_sigtype_is(pgp, SIGTYPE_DIRECT_KEY)) {
if (!recog_signature(pgp, &signature)) {
printf("recog_primary_key: no signature/trust at PGPV_SIGTYPE_DIRECT_KEY\n");
return 0;
}
if (signature.keyexpiry) {
/* XXX - check it's a good key expiry */
primary->primary.expiry = signature.keyexpiry;
}
ARRAY_APPEND(primary->direct_sigs, signature);
}
/* some keys out there have user ids where they shouldn't */
do {
if (!recog_userid(pgp, &userid)) {
printf("recog_primary_key: not userid\n");
return 0;
}
ARRAY_APPEND(primary->signed_userids, userid);
if (userid.primary_userid) {
primary->primary_userid = ARRAY_COUNT(primary->signed_userids) - 1;
}
while (pkt_is(pgp, USERID_PKT)) {
if (!recog_userid(pgp, &userid)) {
printf("recog_primary_key: not signed secondary userid\n");
return 0;
}
ARRAY_APPEND(primary->signed_userids, userid);
if (userid.primary_userid) {
primary->primary_userid = ARRAY_COUNT(primary->signed_userids) - 1;
}
}
while (pkt_is(pgp, USER_ATTRIBUTE_PKT)) {
if (!recog_userattr(pgp, &userattr)) {
printf("recog_primary_key: not signed user attribute\n");
return 0;
}
ARRAY_APPEND(primary->signed_userattrs, userattr);
}
while (pkt_is(pgp, PUB_SUBKEY_PKT)) {
if (!recog_subkey(pgp, &subkey)) {
printf("recog_primary_key: not signed public subkey\n");
return 0;
}
pgpv_calc_keyid(&subkey.subkey);
ARRAY_APPEND(primary->signed_subkeys, subkey);
}
} while (pgp->pkt < ARRAY_COUNT(pgp->pkts) && pkt_is(pgp, USERID_PKT));
primary->fmtsize = estimate_primarykey_size(primary);
return 1;
}
/* parse all of the packets for a given operation */
static int
read_all_packets(pgpv_t *pgp, pgpv_mem_t *mem, const char *op)
{
pgpv_primarykey_t primary;
if (op == NULL) {
return 0;
}
if (strcmp(pgp->op = op, "pubring") == 0) {
mem->allowed = PUBRING_ALLOWED;
/* pubrings have thousands of small packets */
ARRAY_EXPAND_SIZED(pgp->pkts, 0, 5000);
} else if (strcmp(op, "signature") == 0) {
mem->allowed = SIGNATURE_ALLOWED;
} else {
mem->allowed = "";
}
for (mem->cc = 0; mem->cc < mem->size ; ) {
if (!read_pkt(pgp, mem)) {
return 0;
}
}
if (strcmp(op, "pubring") == 0) {
for (pgp->pkt = 0; pgp->pkt < ARRAY_COUNT(pgp->pkts) && recog_primary_key(pgp, &primary) ; ) {
pgpv_calc_keyid(&primary.primary);
ARRAY_APPEND(pgp->primaries, primary);
}
if (pgp->pkt < ARRAY_COUNT(pgp->pkts)) {
printf("short pubring recognition???\n");
}
}
pgp->pkt = ARRAY_COUNT(pgp->pkts);
return 1;
}
/* create a filename, read it, and then parse according to "op" */
static int
read_binary_file(pgpv_t *pgp, const char *op, const char *fmt, ...)
{
va_list args;
char buf[1024];
va_start(args, fmt);
vsnprintf(buf, sizeof(buf), fmt, args);
va_end(args);
if (!read_file(pgp, buf)) {
return 0;
}
return read_all_packets(pgp, &ARRAY_LAST(pgp->areas), op);
}
/* parse memory according to "op" */
static int
read_binary_memory(pgpv_t *pgp, const char *op, const void *memory, size_t size)
{
pgpv_mem_t *mem;
ARRAY_EXPAND(pgp->areas);
ARRAY_COUNT(pgp->areas) += 1;
mem = &ARRAY_LAST(pgp->areas);
memset(mem, 0x0, sizeof(*mem));
mem->size = size;
mem->mem = __UNCONST(memory);
mem->dealloc = 0;
return read_all_packets(pgp, mem, op);
}
/* fixup the detached signature packets */
static int
fixup_detached(pgpv_cursor_t *cursor, const char *f)
{
pgpv_onepass_t *onepass;
const char *dot;
pgpv_pkt_t sigpkt;
pgpv_pkt_t litdata;
pgpv_mem_t *mem;
size_t el;
char original[MAXPATHLEN];
/* cons up litdata pkt */
if ((dot = strrchr(f, '.')) == NULL || strcasecmp(dot, ".sig") != 0) {
printf("weird filename '%s'\n", f);
return 0;
}
/* hold sigpkt in a temp var while we insert onepass and litdata */
el = ARRAY_COUNT(cursor->pgp->pkts) - 1;
sigpkt = ARRAY_ELEMENT(cursor->pgp->pkts, el);
ARRAY_DELETE(cursor->pgp->pkts, el);
ARRAY_EXPAND(cursor->pgp->pkts);
/* get onepass packet, append to packets */
read_binary_memory(cursor->pgp, "signature", cons_onepass, 15);
onepass = &ARRAY_ELEMENT(cursor->pgp->pkts, el).u.onepass;
/* read the original file into litdata */
snprintf(original, sizeof(original), "%.*s", (int)(dot - f), f);
if (!read_file(cursor->pgp, original)) {
printf("can't read file '%s'\n", original);
return 0;
}
memset(&litdata, 0x0, sizeof(litdata));
mem = &ARRAY_LAST(cursor->pgp->areas);
litdata.tag = LITDATA_PKT;
litdata.s.data = mem->mem;
litdata.u.litdata.format = LITDATA_BINARY;
litdata.u.litdata.offset = 0;
litdata.u.litdata.filename = (uint8_t *)strdup(original);
litdata.u.litdata.mem = ARRAY_COUNT(cursor->pgp->areas) - 1;
litdata.u.litdata.len = litdata.s.size = mem->size;
ARRAY_APPEND(cursor->pgp->pkts, litdata);
ARRAY_APPEND(cursor->pgp->pkts, sigpkt);
memcpy(onepass->keyid, sigpkt.u.sigpkt.sig.signer, sizeof(onepass->keyid));
onepass->hashalg = sigpkt.u.sigpkt.sig.hashalg;
onepass->keyalg = sigpkt.u.sigpkt.sig.keyalg;
return 1;
}
/* match the calculated signature against the oen in the signature packet */
static int
match_sig(pgpv_cursor_t *cursor, pgpv_signature_t *signature, pgpv_pubkey_t *pubkey, uint8_t *data, size_t size)
{
unsigned calclen;
uint8_t calculated[64];
int match;
calclen = pgpv_digest_memory(calculated, sizeof(calculated),
data, size,
get_ref(&signature->hashstart), signature->hashlen,
(signature->type == SIGTYPE_TEXT) ? 't' : 'b');
if (ALG_IS_RSA(signature->keyalg)) {
match = rsa_verify(calculated, calclen, signature->hashalg, signature->bn, pubkey);
} else if (ALG_IS_DSA(signature->keyalg)) {
match = verify_dsa_sig(calculated, calclen, signature->bn, pubkey);
} else {
snprintf(cursor->why, sizeof(cursor->why), "Signature type %u not recognised", signature->keyalg);
return 0;
}
if (!match && signature->type == SIGTYPE_TEXT) {
/* second try for cleartext data, ignoring trailing whitespace */
calclen = pgpv_digest_memory(calculated, sizeof(calculated),
data, size,
get_ref(&signature->hashstart), signature->hashlen, 'w');
if (ALG_IS_RSA(signature->keyalg)) {
match = rsa_verify(calculated, calclen, signature->hashalg, signature->bn, pubkey);
} else if (ALG_IS_DSA(signature->keyalg)) {
match = verify_dsa_sig(calculated, calclen, signature->bn, pubkey);
}
}
if (!match) {
snprintf(cursor->why, sizeof(cursor->why), "Signature on data did not match");
return 0;
}
if (valid_dates(signature, pubkey, cursor->why, sizeof(cursor->why)) > 0) {
return 0;
}
if (key_expired(pubkey, cursor->why, sizeof(cursor->why))) {
return 0;
}
if (signature->revoked) {
snprintf(cursor->why, sizeof(cursor->why), "Signature was revoked");
return 0;
}
return 1;
}
/* check return value from getenv */
static const char *
nonnull_getenv(const char *key)
{
char *value;
return ((value = getenv(key)) == NULL) ? "" : value;
}
/************************************************************************/
/* start of exported functions */
/************************************************************************/
/* close all stuff */
int
pgpv_close(pgpv_t *pgp)
{
unsigned i;
if (pgp == NULL) {
return 0;
}
for (i = 0 ; i < ARRAY_COUNT(pgp->areas) ; i++) {
if (ARRAY_ELEMENT(pgp->areas, i).size > 0) {
closemem(&ARRAY_ELEMENT(pgp->areas, i));
}
}
return 1;
}
/* return the formatted entry for the primary key desired */
size_t
pgpv_get_entry(pgpv_t *pgp, unsigned ent, char **ret)
{
size_t cc;
if (ret == NULL || pgp == NULL || ent >= ARRAY_COUNT(pgp->primaries)) {
return 0;
}
*ret = NULL;
cc = ARRAY_ELEMENT(pgp->primaries, ent).fmtsize;
if ((*ret = calloc(1, cc)) == NULL) {
return 0;
}
return fmt_primary(*ret, cc, &ARRAY_ELEMENT(pgp->primaries, ent));
}
/* find key id */
int
pgpv_find_keyid(pgpv_t *pgp, const char *strkeyid, uint8_t *keyid)
{
unsigned i;
uint8_t binkeyid[PGPV_KEYID_LEN];
size_t off;
size_t cmp;
if (strkeyid == NULL && keyid == NULL) {
return 0;
}
if (strkeyid) {
str_to_keyid(strkeyid, binkeyid);
cmp = strlen(strkeyid) / 2;
} else {
memcpy(binkeyid, keyid, sizeof(binkeyid));
cmp = PGPV_KEYID_LEN;
}
off = PGPV_KEYID_LEN - cmp;
for (i = 0 ; i < ARRAY_COUNT(pgp->primaries) ; i++) {
if (memcmp(&ARRAY_ELEMENT(pgp->primaries, i).primary.keyid[off], &binkeyid[off], cmp) == 0) {
return i;
}
}
return -1;
}
/* verify the signed packets we have */
size_t
pgpv_verify(pgpv_cursor_t *cursor, pgpv_t *pgp, const void *p, ssize_t size)
{
pgpv_signature_t *signature;
pgpv_onepass_t *onepass;
pgpv_litdata_t *litdata;
pgpv_pubkey_t *pubkey;
unsigned primary;
uint8_t *data;
size_t pkt;
size_t insize;
char strkeyid[PGPV_STR_KEYID_LEN];
int j;
if (cursor == NULL || pgp == NULL || p == NULL) {
return 0;
}
if (!setup_data(cursor, pgp, p, size)) {
snprintf(cursor->why, sizeof(cursor->why), "No input data");
return 0;
}
if (ARRAY_COUNT(cursor->pgp->pkts) == ARRAY_LAST(cursor->pgp->datastarts) + 1) {
/* got detached signature here */
if (!fixup_detached(cursor, p)) {
snprintf(cursor->why, sizeof(cursor->why), "Can't read signed file '%s'", (const char *)p);
return 0;
}
}
if ((pkt = find_onepass(cursor, ARRAY_LAST(cursor->pgp->datastarts))) == 0) {
snprintf(cursor->why, sizeof(cursor->why), "No signature found");
return 0;
}
pkt -= 1;
onepass = &ARRAY_ELEMENT(cursor->pgp->pkts, pkt).u.onepass;
litdata = &ARRAY_ELEMENT(cursor->pgp->pkts, pkt + 1).u.litdata;
signature = &ARRAY_ELEMENT(cursor->pgp->pkts, pkt + 2).u.sigpkt.sig;
/* sanity check values in signature and onepass agree */
if (signature->birth == 0) {
fmt_time(cursor->why, sizeof(cursor->why), "Signature creation time [",
signature->birth, "] out of range", 0);
return 0;
}
if (memcmp(onepass->keyid, signature->signer, PGPV_KEYID_LEN) != 0) {
fmt_binary(strkeyid, sizeof(strkeyid), onepass->keyid, (unsigned)sizeof(onepass->keyid));
snprintf(cursor->why, sizeof(cursor->why), "Signature key id %s does not match onepass keyid",
strkeyid);
return 0;
}
if (onepass->hashalg != signature->hashalg) {
snprintf(cursor->why, sizeof(cursor->why), "Signature hashalg %u does not match onepass hashalg %u",
signature->hashalg, onepass->hashalg);
return 0;
}
if (onepass->keyalg != signature->keyalg) {
snprintf(cursor->why, sizeof(cursor->why), "Signature keyalg %u does not match onepass keyalg %u",
signature->keyalg, onepass->keyalg);
return 0;
}
if ((j = pgpv_find_keyid(cursor->pgp, NULL, onepass->keyid)) < 0) {
fmt_binary(strkeyid, sizeof(strkeyid), onepass->keyid, (unsigned)sizeof(onepass->keyid));
snprintf(cursor->why, sizeof(cursor->why), "Signature key id %s not found ", strkeyid);
return 0;
}
primary = (unsigned)j;
pubkey = &ARRAY_ELEMENT(cursor->pgp->primaries, primary).primary;
cursor->sigtime = signature->birth;
/* calc hash on data packet */
data = get_literal_data(cursor, litdata, &insize);
if (!match_sig(cursor, signature, pubkey, data, insize)) {
return 0;
}
ARRAY_APPEND(cursor->datacookies, pkt);
ARRAY_APPEND(cursor->found, primary);
return pkt + 1;
}
/* set up the pubkey keyring */
int
pgpv_read_pubring(pgpv_t *pgp, const void *keyring, ssize_t size)
{
if (pgp == NULL) {
return 0;
}
if (keyring) {
return (size > 0) ?
read_binary_memory(pgp, "pubring", keyring, (size_t)size) :
read_binary_file(pgp, "pubring", "%s", (const char *)keyring);
}
return read_binary_file(pgp, "pubring", "%s/%s", nonnull_getenv("HOME"), ".gnupg/pubring.gpg");
}
/* get verified data as a string, return its size */
size_t
pgpv_get_verified(pgpv_cursor_t *cursor, size_t cookie, char **ret)
{
pgpv_litdata_t *litdata;
uint8_t *data;
size_t size;
size_t pkt;
if (ret == NULL || cursor == NULL || cookie == 0) {
return 0;
}
*ret = NULL;
if ((pkt = find_onepass(cursor, cookie - 1)) == 0) {
return 0;
}
litdata = &ARRAY_ELEMENT(cursor->pgp->pkts, pkt).u.litdata;
data = get_literal_data(cursor, litdata, &size);
if ((*ret = calloc(1, size)) == NULL) {
return 0;
}
memcpy(*ret, data, size);
return size;
}
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