rpm/sign/rpmgensig.c

605 lines
14 KiB
C

/** \ingroup rpmcli
* \file lib/rpmchecksig.c
* Verify the signature of a package.
*/
#include "system.h"
#include <errno.h>
#include <sys/wait.h>
#include <popt.h>
#include <rpm/rpmlib.h> /* RPMSIGTAG & related */
#include <rpm/rpmmacro.h>
#include <rpm/rpmpgp.h>
#include <rpm/rpmsign.h>
#include <rpm/rpmfileutil.h> /* rpmMkTemp() */
#include <rpm/rpmlog.h>
#include <rpm/rpmstring.h>
#include "lib/rpmlead.h"
#include "lib/signature.h"
#include "debug.h"
#if !defined(__GLIBC__) && !defined(__APPLE__)
char ** environ = NULL;
#endif
static int closeFile(FD_t *fdp)
{
if (fdp == NULL || *fdp == NULL)
return 1;
/* close and reset *fdp to NULL */
(void) Fclose(*fdp);
*fdp = NULL;
return 0;
}
/**
*/
static int manageFile(FD_t *fdp, const char *fn, int flags)
{
FD_t fd;
if (fdp == NULL || fn == NULL) /* programmer error */
return 1;
/* open a file and set *fdp */
if (*fdp == NULL && fn != NULL) {
fd = Fopen(fn, (flags & O_ACCMODE) == O_WRONLY ? "w.ufdio" : "r.ufdio");
if (fd == NULL || Ferror(fd)) {
rpmlog(RPMLOG_ERR, _("%s: open failed: %s\n"), fn,
Fstrerror(fd));
return 1;
}
*fdp = fd;
return 0;
}
/* no operation */
if (*fdp != NULL && fn != NULL)
return 0;
/* XXX never reached */
return 1;
}
/**
* Copy header+payload, calculating digest(s) on the fly.
*/
static int copyFile(FD_t *sfdp, const char *sfnp,
FD_t *tfdp, const char *tfnp)
{
unsigned char buf[BUFSIZ];
ssize_t count;
int rc = 1;
if (manageFile(sfdp, sfnp, O_RDONLY))
goto exit;
if (manageFile(tfdp, tfnp, O_WRONLY|O_CREAT|O_TRUNC))
goto exit;
while ((count = Fread(buf, sizeof(buf[0]), sizeof(buf), *sfdp)) > 0)
{
if (Fwrite(buf, sizeof(buf[0]), count, *tfdp) != count) {
rpmlog(RPMLOG_ERR, _("%s: Fwrite failed: %s\n"), tfnp,
Fstrerror(*tfdp));
goto exit;
}
}
if (count < 0) {
rpmlog(RPMLOG_ERR, _("%s: Fread failed: %s\n"), sfnp, Fstrerror(*sfdp));
goto exit;
}
if (Fflush(*tfdp) != 0) {
rpmlog(RPMLOG_ERR, _("%s: Fflush failed: %s\n"), tfnp,
Fstrerror(*tfdp));
}
rc = 0;
exit:
if (*sfdp) (void) closeFile(sfdp);
if (*tfdp) (void) closeFile(tfdp);
return rc;
}
/*
* Validate generated signature and insert to header if it looks sane.
* NSS doesn't support everything GPG does. Basic tests to see if the
* generated signature is something we can use.
* Return 0 on success, 1 on failure.
*/
static int putSignature(Header sigh, int ishdr, uint8_t *pkt, size_t pktlen)
{
pgpDigParams sigp = NULL;
rpmTagVal sigtag;
struct rpmtd_s sigtd;
int rc = 1; /* assume failure */
unsigned int hash_algo;
unsigned int pubkey_algo;
if (pgpPrtParams(pkt, pktlen, PGPTAG_SIGNATURE, &sigp)) {
rpmlog(RPMLOG_ERR, _("Unsupported PGP signature\n"));
goto exit;
}
hash_algo = pgpDigParamsAlgo(sigp, PGPVAL_HASHALGO);
if (rpmDigestLength(hash_algo) == 0) {
rpmlog(RPMLOG_ERR, _("Unsupported PGP hash algorithm %u\n"), hash_algo);
goto exit;
}
pubkey_algo = pgpDigParamsAlgo(sigp, PGPVAL_PUBKEYALGO);
switch (pubkey_algo) {
case PGPPUBKEYALGO_DSA:
sigtag = ishdr ? RPMSIGTAG_DSA : RPMSIGTAG_GPG;
break;
case PGPPUBKEYALGO_RSA:
sigtag = ishdr ? RPMSIGTAG_RSA : RPMSIGTAG_PGP;
break;
default:
rpmlog(RPMLOG_ERR, _("Unsupported PGP pubkey algorithm %u\n"),
pubkey_algo);
goto exit;
break;
}
/* Looks sane, insert into header */
rpmtdReset(&sigtd);
sigtd.count = pktlen;
sigtd.data = pkt;
sigtd.type = RPM_BIN_TYPE;
sigtd.tag = sigtag;
/* Argh, reversed return codes */
rc = (headerPut(sigh, &sigtd, HEADERPUT_DEFAULT) == 0);
exit:
pgpDigParamsFree(sigp);
return rc;
}
static int runGPG(const char *file, const char *sigfile, const char * passPhrase)
{
int pid, status;
int inpipe[2];
FILE * fpipe;
int rc = 1; /* assume failure */
inpipe[0] = inpipe[1] = 0;
if (pipe(inpipe) < 0) {
rpmlog(RPMLOG_ERR, _("Couldn't create pipe for signing: %m"));
goto exit;
}
addMacro(NULL, "__plaintext_filename", NULL, file, -1);
addMacro(NULL, "__signature_filename", NULL, sigfile, -1);
if (!(pid = fork())) {
char *const *av;
char *cmd = NULL;
const char *gpg_path = rpmExpand("%{?_gpg_path}", NULL);
(void) dup2(inpipe[0], 3);
(void) close(inpipe[1]);
if (gpg_path && *gpg_path != '\0')
(void) setenv("GNUPGHOME", gpg_path, 1);
(void) setenv("LC_ALL", "C", 1);
unsetenv("MALLOC_CHECK_");
cmd = rpmExpand("%{?__gpg_sign_cmd}", NULL);
rc = poptParseArgvString(cmd, NULL, (const char ***)&av);
if (!rc)
rc = execve(av[0], av+1, environ);
rpmlog(RPMLOG_ERR, _("Could not exec %s: %s\n"), "gpg",
strerror(errno));
_exit(EXIT_FAILURE);
}
delMacro(NULL, "__plaintext_filename");
delMacro(NULL, "__signature_filename");
fpipe = fdopen(inpipe[1], "w");
(void) close(inpipe[0]);
if (fpipe) {
fprintf(fpipe, "%s\n", (passPhrase ? passPhrase : ""));
(void) fclose(fpipe);
}
(void) waitpid(pid, &status, 0);
if (!WIFEXITED(status) || WEXITSTATUS(status)) {
rpmlog(RPMLOG_ERR, _("gpg exec failed (%d)\n"), WEXITSTATUS(status));
} else {
rc = 0;
}
exit:
return rc;
}
/**
* Generate GPG signature(s) for a header+payload file.
* @param sigh signature header
* @param ishdr header-only signature?
* @param file header+payload file name
* @param passPhrase private key pass phrase
* @return 0 on success, 1 on failure
*/
static int makeGPGSignature(Header sigh, int ishdr,
const char * file, const char * passPhrase)
{
char * sigfile = rstrscat(NULL, file, ".sig", NULL);
struct stat st;
uint8_t * pkt = NULL;
size_t pktlen = 0;
int rc = 1; /* assume failure */
if (runGPG(file, sigfile, passPhrase))
goto exit;
if (stat(sigfile, &st)) {
/* GPG failed to write signature */
rpmlog(RPMLOG_ERR, _("gpg failed to write signature\n"));
goto exit;
}
pktlen = st.st_size;
rpmlog(RPMLOG_DEBUG, "GPG sig size: %zd\n", pktlen);
pkt = xmalloc(pktlen);
{ FD_t fd;
rc = 0;
fd = Fopen(sigfile, "r.ufdio");
if (fd != NULL && !Ferror(fd)) {
rc = Fread(pkt, sizeof(*pkt), pktlen, fd);
(void) Fclose(fd);
}
if (rc != pktlen) {
rpmlog(RPMLOG_ERR, _("unable to read the signature\n"));
goto exit;
}
}
rpmlog(RPMLOG_DEBUG, "Got %zd bytes of GPG sig\n", pktlen);
/* Parse the signature, change signature tag as appropriate. */
rc = putSignature(sigh, ishdr, pkt, pktlen);
exit:
(void) unlink(sigfile);
free(sigfile);
free(pkt);
return rc;
}
/**
* Generate header only signature(s) from a header+payload file.
* @param sigh signature header
* @param file header+payload file name
* @param passPhrase private key pass phrase
* @return 0 on success, -1 on failure
*/
static int makeHDRSignature(Header sigh, const char * file,
const char * passPhrase)
{
Header h = NULL;
FD_t fd = NULL;
char * fn = NULL;
int ret = -1; /* assume failure. */
fd = Fopen(file, "r.fdio");
if (fd == NULL || Ferror(fd))
goto exit;
h = headerRead(fd, HEADER_MAGIC_YES);
if (h == NULL)
goto exit;
(void) Fclose(fd);
fd = rpmMkTempFile(NULL, &fn);
if (fd == NULL || Ferror(fd))
goto exit;
if (headerWrite(fd, h, HEADER_MAGIC_YES))
goto exit;
ret = makeGPGSignature(sigh, 1, fn, passPhrase);
exit:
if (fn) {
(void) unlink(fn);
free(fn);
}
headerFree(h);
if (fd != NULL) (void) Fclose(fd);
return ret;
}
static int rpmGenSignature(Header sigh, const char * file,
const char * passPhrase)
{
int ret = -1; /* assume failure. */
if (makeGPGSignature(sigh, 0, file, passPhrase) == 0) {
/* XXX Piggyback a header-only DSA/RSA signature as well. */
ret = makeHDRSignature(sigh, file, passPhrase);
}
return ret;
}
/**
* Retrieve signature from header tag
* @param sigh signature header
* @param sigtag signature tag
* @return parsed pgp dig or NULL
*/
static pgpDigParams getSig(Header sigh, rpmTagVal sigtag)
{
struct rpmtd_s pkt;
pgpDigParams sig = NULL;
if (headerGet(sigh, sigtag, &pkt, HEADERGET_DEFAULT) && pkt.data != NULL) {
pgpPrtParams(pkt.data, pkt.count, PGPTAG_SIGNATURE, &sig);
rpmtdFreeData(&pkt);
}
return sig;
}
static void deleteSigs(Header sigh)
{
headerDel(sigh, RPMSIGTAG_GPG);
headerDel(sigh, RPMSIGTAG_PGP);
headerDel(sigh, RPMSIGTAG_DSA);
headerDel(sigh, RPMSIGTAG_RSA);
headerDel(sigh, RPMSIGTAG_PGP5);
}
static int sameSignature(rpmTagVal sigtag, Header h1, Header h2)
{
pgpDigParams sig1 = getSig(h1, sigtag);
pgpDigParams sig2 = getSig(h2, sigtag);;
int rc = pgpDigParamsCmp(sig1, sig2);
pgpDigParamsFree(sig1);
pgpDigParamsFree(sig2);
return (rc == 0);
}
static int replaceSignature(Header sigh, const char *sigtarget,
const char *passPhrase)
{
/* Grab a copy of the header so we can compare the result */
Header oldsigh = headerCopy(sigh);
int rc = -1;
/* Nuke all signature tags */
deleteSigs(sigh);
/*
* rpmGenSignature() internals parse the actual signing result and
* adds appropriate tags for DSA/RSA.
*/
if (rpmGenSignature(sigh, sigtarget, passPhrase) == 0) {
/* Lets see what we got and whether its the same signature as before */
rpmTagVal sigtag = headerIsEntry(sigh, RPMSIGTAG_DSA) ?
RPMSIGTAG_DSA : RPMSIGTAG_RSA;
rc = sameSignature(sigtag, sigh, oldsigh);
}
headerFree(oldsigh);
return rc;
}
/** \ingroup rpmcli
* Create/modify elements in signature header.
* @param rpm path to package
* @param deleting adding or deleting signature?
* @param passPhrase passPhrase (ignored when deleting)
* @return 0 on success, -1 on error
*/
static int rpmSign(const char *rpm, int deleting, const char *passPhrase)
{
FD_t fd = NULL;
FD_t ofd = NULL;
rpmlead lead = NULL;
char *sigtarget = NULL, *trpm = NULL;
Header sigh = NULL;
char * msg = NULL;
int res = -1; /* assume failure */
rpmRC rc;
struct rpmtd_s utd;
fprintf(stdout, "%s:\n", rpm);
if (manageFile(&fd, rpm, O_RDONLY))
goto exit;
if ((rc = rpmLeadRead(fd, &lead, NULL, &msg)) != RPMRC_OK) {
rpmlog(RPMLOG_ERR, "%s: %s\n", rpm, msg);
free(msg);
goto exit;
}
rc = rpmReadSignature(fd, &sigh, RPMSIGTYPE_HEADERSIG, &msg);
switch (rc) {
default:
rpmlog(RPMLOG_ERR, _("%s: rpmReadSignature failed: %s"), rpm,
(msg && *msg ? msg : "\n"));
msg = _free(msg);
goto exit;
break;
case RPMRC_OK:
if (sigh == NULL) {
rpmlog(RPMLOG_ERR, _("%s: No signature available\n"), rpm);
goto exit;
}
break;
}
msg = _free(msg);
ofd = rpmMkTempFile(NULL, &sigtarget);
if (ofd == NULL || Ferror(ofd)) {
rpmlog(RPMLOG_ERR, _("rpmMkTemp failed\n"));
goto exit;
}
/* Write the header and archive to a temp file */
if (copyFile(&fd, rpm, &ofd, sigtarget))
goto exit;
/* Both fd and ofd are now closed. sigtarget contains tempfile name. */
/* Dump the immutable region (if present). */
if (headerGet(sigh, RPMTAG_HEADERSIGNATURES, &utd, HEADERGET_DEFAULT)) {
struct rpmtd_s copytd;
Header nh = headerNew();
Header oh = headerCopyLoad(utd.data);
HeaderIterator hi = headerInitIterator(oh);
while (headerNext(hi, &copytd)) {
if (copytd.data)
headerPut(nh, &copytd, HEADERPUT_DEFAULT);
rpmtdFreeData(&copytd);
}
headerFreeIterator(hi);
headerFree(oh);
headerFree(sigh);
sigh = headerLink(nh);
headerFree(nh);
}
/* Eliminate broken digest values. */
headerDel(sigh, RPMSIGTAG_BADSHA1_1);
headerDel(sigh, RPMSIGTAG_BADSHA1_2);
/* Toss and recalculate header+payload size and digests. */
{
rpmTagVal const sigs[] = { RPMSIGTAG_SIZE,
RPMSIGTAG_MD5,
RPMSIGTAG_SHA1,
};
int nsigs = sizeof(sigs) / sizeof(rpmTagVal);
for (int i = 0; i < nsigs; i++) {
(void) headerDel(sigh, sigs[i]);
if (rpmGenDigest(sigh, sigtarget, sigs[i]))
goto exit;
}
}
if (deleting) { /* Nuke all the signature tags. */
deleteSigs(sigh);
} else {
res = replaceSignature(sigh, sigtarget, passPhrase);
if (res != 0) {
if (res == 1) {
rpmlog(RPMLOG_WARNING,
_("%s already contains identical signature, skipping\n"),
rpm);
/* Identical signature is not an error */
res = 0;
}
goto exit;
}
}
/* Reallocate the signature into one contiguous region. */
sigh = headerReload(sigh, RPMTAG_HEADERSIGNATURES);
if (sigh == NULL) /* XXX can't happen */
goto exit;
rasprintf(&trpm, "%s.XXXXXX", rpm);
ofd = rpmMkTemp(trpm);
if (ofd == NULL || Ferror(ofd)) {
rpmlog(RPMLOG_ERR, _("rpmMkTemp failed\n"));
goto exit;
}
/* Write the lead/signature of the output rpm */
rc = rpmLeadWrite(ofd, lead);
if (rc != RPMRC_OK) {
rpmlog(RPMLOG_ERR, _("%s: writeLead failed: %s\n"), trpm,
Fstrerror(ofd));
goto exit;
}
if (rpmWriteSignature(ofd, sigh)) {
rpmlog(RPMLOG_ERR, _("%s: rpmWriteSignature failed: %s\n"), trpm,
Fstrerror(ofd));
goto exit;
}
/* Append the header and archive from the temp file */
if (copyFile(&fd, sigtarget, &ofd, trpm) == 0) {
struct stat st;
/* Move final target into place, restore file permissions. */
if (stat(rpm, &st) == 0 && unlink(rpm) == 0 &&
rename(trpm, rpm) == 0 && chmod(rpm, st.st_mode) == 0) {
res = 0;
} else {
rpmlog(RPMLOG_ERR, _("replacing %s failed: %s\n"),
rpm, strerror(errno));
}
}
exit:
if (fd) (void) closeFile(&fd);
if (ofd) (void) closeFile(&ofd);
rpmFreeSignature(sigh);
rpmLeadFree(lead);
/* Clean up intermediate target */
if (sigtarget) {
unlink(sigtarget);
free(sigtarget);
}
if (trpm) {
(void) unlink(trpm);
free(trpm);
}
return res;
}
int rpmPkgSign(const char *path,
const struct rpmSignArgs * args, const char *passPhrase)
{
int rc;
if (args) {
if (args->hashalgo) {
char *algo = NULL;
rasprintf(&algo, "%d", args->hashalgo);
addMacro(NULL, "_gpg_digest_algo", NULL, algo, RMIL_GLOBAL);
free(algo);
}
if (args->keyid) {
addMacro(NULL, "_gpg_name", NULL, args->keyid, RMIL_GLOBAL);
}
}
rc = rpmSign(path, 0, passPhrase);
if (args) {
if (args->hashalgo) {
delMacro(NULL, "_gpg_digest_algo");
}
if (args->keyid) {
delMacro(NULL, "_gpg_name");
}
}
return rc;
}
int rpmPkgDelSign(const char *path)
{
return rpmSign(path, 1, NULL);
}