static bool quiet;
+/*
+ * ucert structure
+ * | BLOB |
+ * | SIGNATURE | PAYLOAD |
+ * | |[ BLOBMSG CONTAINER ]|
+ * | |[[T,i,v,e,f,pubkey ]]|
+ */
enum cert_attr {
CERT_ATTR_SIGNATURE,
CERT_ATTR_PAYLOAD,
[CERT_ATTR_PAYLOAD] = { .type = BLOB_ATTR_NESTED },
};
+enum cert_cont_attr {
+ CERT_CT_ATTR_PAYLOAD,
+ CERT_CT_ATTR_MAX
+};
+
+static const struct blobmsg_policy cert_cont_policy[CERT_CT_ATTR_MAX] = {
+ [CERT_CT_ATTR_PAYLOAD] = { .name = "ucert", .type = BLOBMSG_TYPE_TABLE },
+};
+
enum cert_payload_attr {
CERT_PL_ATTR_CERTTYPE,
CERT_PL_ATTR_CERTID,
};
static const struct blobmsg_policy cert_payload_policy[CERT_PL_ATTR_MAX] = {
- [CERT_PL_ATTR_CERTTYPE] = { .name = "certtype", .type = BLOBMSG_TYPE_INT8 },
- [CERT_PL_ATTR_CERTID] = { .name = "certid", .type = BLOBMSG_TYPE_INT64 },
+ [CERT_PL_ATTR_CERTTYPE] = { .name = "certtype", .type = BLOBMSG_TYPE_INT32 },
+ [CERT_PL_ATTR_CERTID] = { .name = "certid", .type = BLOBMSG_TYPE_INT32 },
[CERT_PL_ATTR_VALIDFROMTIME] = { .name = "validfrom", .type = BLOBMSG_TYPE_INT64 },
[CERT_PL_ATTR_EXPIRETIME] = { .name = "expiresat", .type = BLOBMSG_TYPE_INT64 },
[CERT_PL_ATTR_PUBKEY] = { .name = "pubkey", .type = BLOBMSG_TYPE_STRING },
[CERT_PL_ATTR_KEY_FINGERPRINT] = { .name = "fingerprint", .type = BLOBMSG_TYPE_STRING },
};
+/* list to store certificate chain at runtime */
+struct cert_object {
+ struct list_head list;
+ struct blob_attr *cert[CERT_ATTR_MAX];
+};
+
+/* write buffer to file */
static int write_file(const char *filename, void *buf, size_t len, bool append) {
FILE *f;
size_t outlen;
return (outlen == len);
}
-static int cert_load(const char *certfile, struct blob_attr *certtb[]) {
+/* load certfile into list */
+static int cert_load(const char *certfile, struct list_head *chain) {
FILE *f;
- int ret = 0;
+ struct blob_attr *certtb[CERT_ATTR_MAX];
+ struct blob_attr *bufpt;
+ struct cert_object *cobj;
char filebuf[CERT_BUF_LEN];
- int len;
+ int ret = 0, pret = 0;
+ int len, pos = 0;
f = fopen(certfile, "r");
if (!f)
return 1;
len = fread(&filebuf, 1, CERT_BUF_LEN - 1, f);
+ if (len < 64)
+ return 1;
+
ret = ferror(f) || !feof(f);
fclose(f);
if (ret)
return 1;
- ret = blob_parse(filebuf, certtb, cert_policy, CERT_ATTR_MAX);
- fprintf(stderr, "blob_parse return %d\n", ret);
- return (ret != 0);
+
+ bufpt = (struct blob_attr *)filebuf;
+ do {
+ pret = blob_parse(bufpt, certtb, cert_policy, CERT_ATTR_MAX);
+ if (pret <= 0)
+ /* no attributes found */
+ break;
+
+ if (pos + blob_pad_len(bufpt) > len)
+ /* blob exceeds filebuffer */
+ break;
+ else
+ pos += blob_pad_len(bufpt);
+
+ if (!certtb[CERT_ATTR_SIGNATURE])
+ /* no signature -> drop */
+ break;
+
+ cobj = calloc(1, sizeof(*cobj));
+ cobj->cert[CERT_ATTR_SIGNATURE] = blob_memdup(certtb[CERT_ATTR_SIGNATURE]);
+ if (certtb[CERT_ATTR_PAYLOAD])
+ cobj->cert[CERT_ATTR_PAYLOAD] = blob_memdup(certtb[CERT_ATTR_PAYLOAD]);
+
+ list_add_tail(&cobj->list, chain);
+ ret += pret;
+ bufpt = blob_next(bufpt);
+ /* repeat parsing while there is still enough remaining data in buffer */
+ } while(len > pos + sizeof(struct blob_attr));
+
+ return (ret <= 0);
}
-static int cert_append(const char *certfile, const char *pubkeyfile, const char *sigfile) {
- fprintf(stderr, "not implemented\n");
- return 1;
+/* append signature to certfile */
+static int cert_append(const char *certfile, const char *sigfile) {
+ FILE *fs;
+ char filebuf[CERT_BUF_LEN];
+ struct blob_buf sigbuf;
+ int len;
+ int ret;
+
+ fs = fopen(sigfile, "r");
+ if (!fs)
+ return 1;
+
+ len = fread(&filebuf, 1, CERT_BUF_LEN - 1, fs);
+ ret = ferror(fs) || !feof(fs) || (len < 64);
+ fclose(fs);
+ if (ret)
+ return 1;
+
+ blob_buf_init(&sigbuf, 0);
+ blob_put(&sigbuf, CERT_ATTR_SIGNATURE, filebuf, len);
+ ret = write_file(certfile, sigbuf.head, blob_raw_len(sigbuf.head), true);
+ blob_buf_free(&sigbuf);
+ return ret;
}
-static int cert_dump(const char *certfile) {
- struct blob_attr *certtb[CERT_ATTR_MAX];
+/* verify the signature of a single chain element */
+static int cert_verify_blob(struct blob_attr *cert[CERT_ATTR_MAX],
+ const char *pubkeyfile, const char *pubkeydir) {
int i;
+ char msgfname[256], sigfname[256];
+ int ret;
+ char tmpdir[] = "/tmp/ucert-XXXXXX";
- if (cert_load(certfile, certtb)) {
- fprintf(stderr, "cannot parse cert\n");
- return 1;
+ if (mkdtemp(tmpdir) == NULL)
+ return errno;
+
+ snprintf(msgfname, sizeof(msgfname) - 1, "%s/%s", tmpdir, "payload");
+ snprintf(sigfname, sizeof(sigfname) - 1, "%s/%s", tmpdir, "payload.sig");
+
+ for (i = 0; i < CERT_ATTR_MAX; i++) {
+ struct blob_attr *v = cert[i];
+
+ if (!v)
+ break;
+
+ switch(cert_policy[i].type) {
+ case BLOB_ATTR_BINARY:
+ write_file(sigfname, blob_data(v), blob_len(v), false);
+ break;
+ case BLOB_ATTR_NESTED:
+ write_file(msgfname, blob_data(v), blob_len(v), false);
+ break;
+ }
}
+ ret = usign_v(msgfname, pubkeyfile, pubkeydir, sigfname, quiet);
+
+ unlink(msgfname);
+ unlink(sigfname);
+ rmdir(tmpdir);
+
+ return ret;
+}
+
+/* verify cert chain (and message) */
+static int chain_verify(const char *msgfile, const char *pubkeyfile,
+ const char *pubkeydir, struct list_head *chain) {
+ struct cert_object *cobj;
+ struct blob_attr *containertb[CERT_CT_ATTR_MAX];
+ struct blob_attr *payloadtb[CERT_PL_ATTR_MAX];
+ char tmpdir[] = "/tmp/ucert-XXXXXX";
+ char chainedpubkey[256] = {0};
+ char chainedfp[17] = {0};
+ char extsigfile[256] = {0};
+ int ret = 1;
+ int checkmsg = 0;
+ struct timeval tv;
+
+ if (mkdtemp(tmpdir) == NULL)
+ return errno;
+
+ if (msgfile)
+ checkmsg = -1;
+
+ gettimeofday(&tv, NULL);
+
+ list_for_each_entry(cobj, chain, list) {
+ /* blob has payload, verify that using signature */
+ if (cobj->cert[CERT_ATTR_PAYLOAD]) {
+ uint64_t validfrom;
+ uint64_t expiresat;
+ uint32_t certtype;
+
+ ret = cert_verify_blob(cobj->cert, chainedpubkey[0]?chainedpubkey:pubkeyfile, pubkeydir);
+ if (ret)
+ goto clean_and_return;
+
+ blobmsg_parse(cert_cont_policy,
+ ARRAY_SIZE(cert_cont_policy),
+ containertb,
+ blob_data(cobj->cert[CERT_ATTR_PAYLOAD]),
+ blob_len(cobj->cert[CERT_ATTR_PAYLOAD]));
+ if (!containertb[CERT_CT_ATTR_PAYLOAD]) {
+ ret = 1;
+ if (!quiet)
+ fprintf(stderr, "no ucert in signed payload\n");
+ goto clean_and_return;
+ }
+ blobmsg_parse(cert_payload_policy,
+ ARRAY_SIZE(cert_payload_policy),
+ payloadtb,
+ blobmsg_data(containertb[CERT_CT_ATTR_PAYLOAD]),
+ blobmsg_data_len(containertb[CERT_CT_ATTR_PAYLOAD]));
+
+ if (!payloadtb[CERT_PL_ATTR_CERTTYPE] ||
+ !payloadtb[CERT_PL_ATTR_VALIDFROMTIME] ||
+ !payloadtb[CERT_PL_ATTR_EXPIRETIME] ||
+ !payloadtb[CERT_PL_ATTR_PUBKEY]) {
+ ret = 1;
+ if (!quiet)
+ fprintf(stderr, "missing mandatory ucert attributes\n");
+ goto clean_and_return;
+ }
+ certtype = blobmsg_get_u32(payloadtb[CERT_PL_ATTR_CERTTYPE]);
+ validfrom = blobmsg_get_u64(payloadtb[CERT_PL_ATTR_VALIDFROMTIME]);
+ expiresat = blobmsg_get_u64(payloadtb[CERT_PL_ATTR_EXPIRETIME]);
+
+ if (certtype != CERTTYPE_AUTH) {
+ ret = 2;
+ if (!quiet)
+ fprintf(stderr, "wrong certificate type\n");
+ goto clean_and_return;
+ }
+
+ if (tv.tv_sec < validfrom ||
+ tv.tv_sec >= expiresat) {
+ ret = 3;
+ if (!quiet)
+ fprintf(stderr, "certificate expired\n");
+ goto clean_and_return;
+ }
+
+ snprintf(chainedpubkey, sizeof(chainedpubkey) - 1, "%s/%s", tmpdir, "chained-pubkey");
+ write_file(chainedpubkey,
+ blobmsg_data(payloadtb[CERT_PL_ATTR_PUBKEY]),
+ blobmsg_data_len(payloadtb[CERT_PL_ATTR_PUBKEY]),
+ false);
+
+ if (usign_f_pubkey(chainedfp, chainedpubkey)) {
+ if (!quiet)
+ fprintf(stderr, "cannot get fingerprint for chained key\n");
+ ret = 2;
+ goto clean_and_return;
+ }
+ if (pubkeydir && _usign_key_is_revoked(chainedfp, pubkeydir)) {
+ if (!quiet)
+ fprintf(stderr, "key %s has been revoked!\n", chainedfp);
+ ret = 4;
+ goto clean_and_return;
+ }
+ } else {
+ /* blob doesn't have payload, verify message using signature */
+ if (msgfile) {
+ snprintf(extsigfile, sizeof(extsigfile) - 1, "%s/%s", tmpdir, "ext-sig");
+ write_file(extsigfile,
+ blob_data(cobj->cert[CERT_ATTR_SIGNATURE]),
+ blob_len(cobj->cert[CERT_ATTR_SIGNATURE]),
+ false);
+ checkmsg = ret = usign_v(msgfile,
+ chainedpubkey[0]?chainedpubkey:pubkeyfile,
+ pubkeydir, extsigfile, quiet);
+ unlink(extsigfile);
+ } else {
+ if (!quiet)
+ fprintf(stderr, "stray trailing signature without anything to verify!\n");
+ ret = 1;
+ };
+ }
+ }
+
+ if (checkmsg == -1 && !quiet)
+ fprintf(stderr, "missing signature to verify message!\n");
+
+clean_and_return:
+ if (chainedpubkey[0])
+ unlink(chainedpubkey);
+ rmdir(tmpdir);
+ return ret | checkmsg;
+}
+
+/* dump single chain element to console */
+static void cert_dump_blob(struct blob_attr *cert[CERT_ATTR_MAX]) {
+ int i;
+
for (i = 0; i < CERT_ATTR_MAX; i++) {
- struct blob_attr *v = certtb[i];
+ struct blob_attr *v = cert[i];
if (!v)
continue;
switch(cert_policy[i].type) {
case BLOB_ATTR_BINARY:
- fprintf(stdout, "signature: %s\n", blob_data(v));
+ fprintf(stdout, "signature:\n---\n%s---\n", (char *) blob_data(v));
break;
case BLOB_ATTR_NESTED:
- fprintf(stdout, "payload:\n%s\n", blobmsg_format_json(blob_data(v), true));
+ fprintf(stdout, "payload:\n---\n%s\n---\n", blobmsg_format_json_indent(blob_data(v), false, 0));
break;
}
}
+}
+
+/* dump certfile to console */
+static int cert_dump(const char *certfile) {
+ struct cert_object *cobj;
+ static LIST_HEAD(certchain);
+ unsigned int count = 0;
+
+ if (cert_load(certfile, &certchain)) {
+ if (!quiet)
+ fprintf(stderr, "cannot parse cert\n");
+ return 1;
+ }
+
+ list_for_each_entry(cobj, &certchain, list) {
+ fprintf(stdout, "=== CHAIN ELEMENT %02u ===\n", ++count);
+ cert_dump_blob(cobj->cert);
+ }
+
return 0;
}
+/* issue an auth certificate for pubkey */
static int cert_issue(const char *certfile, const char *pubkeyfile, const char *seckeyfile) {
struct blob_buf certbuf;
struct blob_buf payloadbuf;
struct timeval tv;
- struct stat st;
int pklen, siglen;
int revoker = 1;
-
+ void *c;
FILE *pkf, *sigf;
char pkb[512];
char sigb[512];
char pkfp[17];
char tmpdir[] = "/tmp/ucert-XXXXXX";
- if (stat(certfile, &st) == 0) {
- fprintf(stderr, "certfile %s exists, won't overwrite.\n", certfile);
- return -1;
- }
-
pkf = fopen(pubkeyfile, "r");
if (!pkf)
return -1;
pklen = fread(pkb, 1, 512, pkf);
- pkb[pklen - 1] = '\0';
+ pkb[pklen] = '\0';
if (pklen < 32)
return -1;
while (revoker >= 0) {
blob_buf_init(&payloadbuf, 0);
- blobmsg_add_u8(&payloadbuf, "certtype", revoker?CERTTYPE_REVOKE:CERTTYPE_AUTH);
+ c = blobmsg_open_table(&payloadbuf, "ucert");
+ blobmsg_add_u32(&payloadbuf, "certtype", revoker?CERTTYPE_REVOKE:CERTTYPE_AUTH);
blobmsg_add_u64(&payloadbuf, "validfrom", tv.tv_sec);
if (!revoker) {
blobmsg_add_u64(&payloadbuf, "expiresat", tv.tv_sec + 60 * 60 * 24 * 365);
blobmsg_add_string(&payloadbuf, "fingerprint", pkfp);
}
+ blobmsg_close_table(&payloadbuf, c);
+
snprintf(fname, sizeof(fname) - 1, "%s/%s", tmpdir, revoker?"revoker":"payload");
write_file(fname, blob_data(payloadbuf.head), blob_len(payloadbuf.head), false);
if (siglen < 1)
return 1;
- sigb[siglen-1] = '\0';
+ sigb[siglen] = '\0';
fclose(sigf);
unlink(fname);
blob_put(&certbuf, CERT_ATTR_SIGNATURE, sigb, siglen);
blob_put(&certbuf, CERT_ATTR_PAYLOAD, blob_data(payloadbuf.head), blob_len(payloadbuf.head));
snprintf(fname, sizeof(fname) - 1, "%s%s", certfile, revoker?".revoke":"");
- write_file(fname, blob_data(certbuf.head), blob_len(certbuf.head), false);
+ write_file(fname, certbuf.head, blob_raw_len(certbuf.head), true);
+ blob_buf_free(&certbuf);
+ blob_buf_free(&payloadbuf);
+
revoker--;
}
return 0;
}
-static int cert_process_revoker(const char *certfile) {
- fprintf(stderr, "not implemented\n");
- return 1;
+/* process revoker certificate */
+static int cert_process_revoker(const char *certfile, const char *pubkeydir) {
+ static LIST_HEAD(certchain);
+ struct cert_object *cobj;
+ struct blob_attr *containertb[CERT_CT_ATTR_MAX];
+ struct blob_attr *payloadtb[CERT_PL_ATTR_MAX];
+ struct stat st;
+ struct timeval tv;
+ uint64_t validfrom;
+ uint32_t certtype;
+ char *fingerprint;
+ char rfname[512];
+
+ int ret;
+
+ if (cert_load(certfile, &certchain)) {
+ if (!quiet)
+ fprintf(stderr, "cannot parse cert\n");
+ return 1;
+ }
+
+ gettimeofday(&tv, NULL);
+
+ list_for_each_entry(cobj, &certchain, list) {
+ if (!cobj->cert[CERT_ATTR_PAYLOAD])
+ return 2;
+
+ /* blob has payload, verify that using signature */
+ ret = cert_verify_blob(cobj->cert, NULL, pubkeydir);
+ if (ret)
+ return ret;
+
+ blobmsg_parse(cert_cont_policy,
+ ARRAY_SIZE(cert_cont_policy),
+ containertb,
+ blob_data(cobj->cert[CERT_ATTR_PAYLOAD]),
+ blob_len(cobj->cert[CERT_ATTR_PAYLOAD]));
+ if (!containertb[CERT_CT_ATTR_PAYLOAD]) {
+ if (!quiet)
+ fprintf(stderr, "no ucert in signed payload\n");
+ return 2;
+ }
+
+ blobmsg_parse(cert_payload_policy,
+ ARRAY_SIZE(cert_payload_policy),
+ payloadtb,
+ blobmsg_data(containertb[CERT_CT_ATTR_PAYLOAD]),
+ blobmsg_data_len(containertb[CERT_CT_ATTR_PAYLOAD]));
+
+ if (!payloadtb[CERT_PL_ATTR_CERTTYPE] ||
+ !payloadtb[CERT_PL_ATTR_VALIDFROMTIME] ||
+ !payloadtb[CERT_PL_ATTR_KEY_FINGERPRINT]) {
+ if (!quiet)
+ fprintf(stderr, "missing mandatory ucert attributes\n");
+ return 2;
+ }
+
+ certtype = blobmsg_get_u32(payloadtb[CERT_PL_ATTR_CERTTYPE]);
+ validfrom = blobmsg_get_u64(payloadtb[CERT_PL_ATTR_VALIDFROMTIME]);
+ fingerprint = blobmsg_get_string(payloadtb[CERT_PL_ATTR_KEY_FINGERPRINT]);
+
+ if (certtype != CERTTYPE_REVOKE) {
+ if (!quiet)
+ fprintf(stderr, "wrong certificate type\n");
+ return 2;
+ }
+
+ if (tv.tv_sec < validfrom) {
+ return 3;
+ }
+
+ snprintf(rfname, sizeof(rfname)-1, "%s/%s", pubkeydir, fingerprint);
+ /* check if entry in pubkeydir exists */
+ if (stat(rfname, &st) == 0) {
+ if (_usign_key_is_revoked(fingerprint, pubkeydir)) {
+ if (!quiet)
+ fprintf(stdout, "existing revoker deadlink for key %s\n", fingerprint);
+ continue;
+ };
+
+ /* remove any other entry */
+ if (unlink(rfname))
+ return -1;
+ }
+
+ ret = symlink(".revoked.", rfname);
+ if (ret)
+ return ret;
+
+ if (!quiet)
+ fprintf(stdout, "created revoker deadlink for key %s\n", fingerprint);
+ };
+
+ return ret;
}
+/* load and verify certfile (and message) */
static int cert_verify(const char *certfile, const char *pubkeyfile, const char *pubkeydir, const char *msgfile) {
- fprintf(stderr, "not implemented\n");
- return 1;
+ static LIST_HEAD(certchain);
+
+ if (cert_load(certfile, &certchain)) {
+ if (!quiet)
+ fprintf(stderr, "cannot parse cert\n");
+ return 1;
+ }
+
+ return chain_verify(msgfile, pubkeyfile, pubkeydir, &certchain);
}
+/* output help */
static int usage(const char *cmd)
{
fprintf(stderr,
"Usage: %s <command> <options>\n"
"Commands:\n"
- " -A: append (needs -c and -p and/or -x)\n"
- " -D: dump\n"
+ " -A: append signature (needs -c and -x)\n"
+ " -D: dump (needs -c)\n"
" -I: issue cert and revoker (needs -c and -p and -s)\n"
- " -R: process revoker certificate (needs -c)\n"
- " -V: verify (needs -c and -p|-P)\n"
+ " -R: process revoker certificate (needs -c and -P)\n"
+ " -V: verify (needs -c and -p|-P, may have -m)\n"
"Options:\n"
" -c <file>: certificate file\n"
" -m <file>: message file (verify only)\n"
return 1;
}
+/* parse command line options and call functions */
int main(int argc, char *argv[]) {
int ch;
const char *msgfile = NULL;
while ((ch = getopt(argc, argv, "ADIRVc:m:p:P:qs:x:")) != -1) {
switch (ch) {
case 'A':
+ if (cmd != CMD_NONE)
+ return usage(argv[0]);
cmd = CMD_APPEND;
break;
case 'D':
+ if (cmd != CMD_NONE)
+ return usage(argv[0]);
cmd = CMD_DUMP;
break;
case 'I':
+ if (cmd != CMD_NONE)
+ return usage(argv[0]);
cmd = CMD_ISSUE;
break;
case 'R':
+ if (cmd != CMD_NONE)
+ return usage(argv[0]);
cmd = CMD_REVOKE;
break;
case 'V':
+ if (cmd != CMD_NONE)
+ return usage(argv[0]);
cmd = CMD_VERIFY;
break;
case 'c':
+ if (certfile || cmd == CMD_NONE)
+ return usage(argv[0]);
certfile = optarg;
break;
case 'm':
+ if (msgfile || cmd != CMD_VERIFY)
+ return usage(argv[0]);
msgfile = optarg;
break;
case 'p':
+ if (pubkeyfile || (cmd != CMD_VERIFY && cmd != CMD_ISSUE) || cmd == CMD_NONE)
+ return usage(argv[0]);
pubkeyfile = optarg;
break;
case 'P':
+ if (pubkeydir || (cmd != CMD_VERIFY && cmd != CMD_REVOKE) || cmd == CMD_NONE)
+ return usage(argv[0]);
pubkeydir = optarg;
break;
- case 's':
- seckeyfile = optarg;
- break;
case 'q':
+ if (quiet)
+ return usage(argv[0]);
quiet = true;
break;
+ case 's':
+ if (seckeyfile || cmd != CMD_ISSUE || cmd == CMD_NONE)
+ return usage(argv[0]);
+ seckeyfile = optarg;
+ break;
case 'x':
+ if (sigfile || cmd != CMD_APPEND || cmd == CMD_NONE)
+ return usage(argv[0]);
sigfile = optarg;
break;
default:
switch (cmd) {
case CMD_APPEND:
- if (certfile && (pubkeyfile || sigfile))
- return cert_append(certfile, pubkeyfile, sigfile);
+ if (certfile && sigfile)
+ return cert_append(certfile, sigfile);
else
return usage(argv[0]);
case CMD_DUMP:
else
return usage(argv[0]);
case CMD_REVOKE:
- if (certfile)
- return cert_process_revoker(certfile);
+ if (certfile && pubkeydir)
+ return cert_process_revoker(certfile, pubkeydir);
else
return usage(argv[0]);
case CMD_VERIFY:
projects / oweals / ucert.git / blobdiff