summaryrefslogtreecommitdiffstats
path: root/security/nss/lib/freebl/shvfy.c
diff options
context:
space:
mode:
Diffstat (limited to 'security/nss/lib/freebl/shvfy.c')
-rw-r--r--security/nss/lib/freebl/shvfy.c534
1 files changed, 534 insertions, 0 deletions
diff --git a/security/nss/lib/freebl/shvfy.c b/security/nss/lib/freebl/shvfy.c
new file mode 100644
index 000000000..af4a34fb0
--- /dev/null
+++ b/security/nss/lib/freebl/shvfy.c
@@ -0,0 +1,534 @@
+
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifdef FREEBL_NO_DEPEND
+#include "stubs.h"
+#endif
+
+#include "shsign.h"
+#include "prlink.h"
+#include "prio.h"
+#include "blapi.h"
+#include "seccomon.h"
+#include "stdio.h"
+#include "prmem.h"
+#include "hasht.h"
+#include "pqg.h"
+#include "blapii.h"
+
+/*
+ * Most modern version of Linux support a speed optimization scheme where an
+ * application called prelink modifies programs and shared libraries to quickly
+ * load if they fit into an already designed address space. In short, prelink
+ * scans the list of programs and libraries on your system, assigns them a
+ * predefined space in the the address space, then provides the fixups to the
+ * library.
+
+ * The modification of the shared library is correctly detected by the freebl
+ * FIPS checksum scheme where we check a signed hash of the library against the
+ * library itself.
+ *
+ * The prelink command itself can reverse the process of modification and
+ * output the prestine shared library as it was before prelink made it's
+ * changes. If FREEBL_USE_PRELINK is set Freebl uses prelink to output the
+ * original copy of the shared library before prelink modified it.
+ */
+#ifdef FREEBL_USE_PRELINK
+#ifndef FREELB_PRELINK_COMMAND
+#define FREEBL_PRELINK_COMMAND "/usr/sbin/prelink -u -o -"
+#endif
+#include "private/pprio.h"
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/wait.h>
+#include <sys/stat.h>
+
+/*
+ * This function returns an NSPR PRFileDesc * which the caller can read to
+ * obtain the prestine value of the shared library, before any OS related
+ * changes to it (usually address fixups).
+ *
+ * If prelink is installed, this
+ * file descriptor is a pipe connecting the output of
+ * /usr/sbin/prelink -u -o - {Library}
+ * and *pid returns the process id of the prelink child.
+ *
+ * If prelink is not installed, it returns a normal readonly handle to the
+ * library itself and *pid is set to '0'.
+ */
+PRFileDesc *
+bl_OpenUnPrelink(const char *shName, int *pid)
+{
+ char *command = strdup(FREEBL_PRELINK_COMMAND);
+ char *argString = NULL;
+ char **argv = NULL;
+ char *shNameArg = NULL;
+ char *cp;
+ pid_t child;
+ int argc = 0, argNext = 0;
+ struct stat statBuf;
+ int pipefd[2] = { -1, -1 };
+ int ret;
+
+ *pid = 0;
+
+ /* make sure the prelink command exists first. If not, fall back to
+ * just reading the file */
+ for (cp = command; *cp; cp++) {
+ if (*cp == ' ') {
+ *cp++ = 0;
+ argString = cp;
+ break;
+ }
+ }
+ memset(&statBuf, 0, sizeof(statBuf));
+ /* stat the file, follow the link */
+ ret = stat(command, &statBuf);
+ if (ret < 0) {
+ free(command);
+ return PR_Open(shName, PR_RDONLY, 0);
+ }
+ /* file exits, make sure it's an executable */
+ if (!S_ISREG(statBuf.st_mode) ||
+ ((statBuf.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0)) {
+ free(command);
+ return PR_Open(shName, PR_RDONLY, 0);
+ }
+
+ /* OK, the prelink command exists and looks correct, use it */
+ /* build the arglist while we can still malloc */
+ /* count the args if any */
+ if (argString && *argString) {
+ /* argString may have leading spaces, strip them off*/
+ for (cp = argString; *cp && *cp == ' '; cp++)
+ ;
+ argString = cp;
+ if (*cp) {
+ /* there is at least one arg.. */
+ argc = 1;
+ }
+
+ /* count the rest: Note there is no provision for escaped
+ * spaces here */
+ for (cp = argString; *cp; cp++) {
+ if (*cp == ' ') {
+ while (*cp && *cp == ' ')
+ cp++;
+ if (*cp)
+ argc++;
+ }
+ }
+ }
+
+ /* add the additional args: argv[0] (command), shName, NULL*/
+ argc += 3;
+ argv = PORT_NewArray(char *, argc);
+ if (argv == NULL) {
+ goto loser;
+ }
+
+ /* fill in the arglist */
+ argv[argNext++] = command;
+ if (argString && *argString) {
+ argv[argNext++] = argString;
+ for (cp = argString; *cp; cp++) {
+ if (*cp == ' ') {
+ *cp++ = 0;
+ while (*cp && *cp == ' ')
+ cp++;
+ if (*cp)
+ argv[argNext++] = cp;
+ }
+ }
+ }
+ /* exec doesn't advertise taking const char **argv, do the paranoid
+ * copy */
+ shNameArg = strdup(shName);
+ if (shNameArg == NULL) {
+ goto loser;
+ }
+ argv[argNext++] = shNameArg;
+ argv[argNext++] = 0;
+
+ ret = pipe(pipefd);
+ if (ret < 0) {
+ goto loser;
+ }
+
+ /* use vfork() so we don't trigger the pthread_at_fork() handlers */
+ child = vfork();
+ if (child < 0)
+ goto loser;
+ if (child == 0) {
+ /* set up the file descriptors */
+ /* if we need to support BSD, this will need to be an open of
+ * /dev/null and dup2(nullFD, 0)*/
+ close(0);
+ /* associate pipefd[1] with stdout */
+ if (pipefd[1] != 1)
+ dup2(pipefd[1], 1);
+ close(2);
+ close(pipefd[0]);
+ /* should probably close the other file descriptors? */
+
+ execv(command, argv);
+ /* avoid at_exit() handlers */
+ _exit(1); /* shouldn't reach here except on an error */
+ }
+ close(pipefd[1]);
+ pipefd[1] = -1;
+
+ /* this is safe because either vfork() as full fork() semantics, and thus
+ * already has it's own address space, or because vfork() has paused
+ * the parent util the exec or exit */
+ free(command);
+ free(shNameArg);
+ PORT_Free(argv);
+
+ *pid = child;
+
+ return PR_ImportPipe(pipefd[0]);
+
+loser:
+ if (pipefd[0] != -1) {
+ close(pipefd[0]);
+ }
+ if (pipefd[1] != -1) {
+ close(pipefd[1]);
+ }
+ free(command);
+ free(shNameArg);
+ PORT_Free(argv);
+
+ return NULL;
+}
+
+/*
+ * bl_CloseUnPrelink -
+ *
+ * This closes the file descripter and reaps and children openned and crated by
+ * b;_OpenUnprelink. It's primary difference between it and just close is
+ * that it calls wait on the pid if one is supplied, preventing zombie children
+ * from hanging around.
+ */
+void
+bl_CloseUnPrelink(PRFileDesc *file, int pid)
+{
+ /* close the file descriptor */
+ PR_Close(file);
+ /* reap the child */
+ if (pid) {
+ waitpid(pid, NULL, 0);
+ }
+}
+#endif
+
+/* #define DEBUG_SHVERIFY 1 */
+
+static char *
+mkCheckFileName(const char *libName)
+{
+ int ln_len = PORT_Strlen(libName);
+ char *output = PORT_Alloc(ln_len + sizeof(SGN_SUFFIX));
+ int index = ln_len + 1 - sizeof("." SHLIB_SUFFIX);
+
+ if ((index > 0) &&
+ (PORT_Strncmp(&libName[index],
+ "." SHLIB_SUFFIX, sizeof("." SHLIB_SUFFIX)) == 0)) {
+ ln_len = index;
+ }
+ PORT_Memcpy(output, libName, ln_len);
+ PORT_Memcpy(&output[ln_len], SGN_SUFFIX, sizeof(SGN_SUFFIX));
+ return output;
+}
+
+static int
+decodeInt(unsigned char *buf)
+{
+ return (buf[3]) | (buf[2] << 8) | (buf[1] << 16) | (buf[0] << 24);
+}
+
+static SECStatus
+readItem(PRFileDesc *fd, SECItem *item)
+{
+ unsigned char buf[4];
+ int bytesRead;
+
+ bytesRead = PR_Read(fd, buf, 4);
+ if (bytesRead != 4) {
+ return SECFailure;
+ }
+ item->len = decodeInt(buf);
+
+ item->data = PORT_Alloc(item->len);
+ if (item->data == NULL) {
+ item->len = 0;
+ return SECFailure;
+ }
+ bytesRead = PR_Read(fd, item->data, item->len);
+ if (bytesRead != item->len) {
+ PORT_Free(item->data);
+ item->data = NULL;
+ item->len = 0;
+ return SECFailure;
+ }
+ return SECSuccess;
+}
+
+static PRBool blapi_SHVerifyFile(const char *shName, PRBool self);
+
+static PRBool
+blapi_SHVerify(const char *name, PRFuncPtr addr, PRBool self)
+{
+ PRBool result = PR_FALSE; /* if anything goes wrong,
+ * the signature does not verify */
+ /* find our shared library name */
+ char *shName = PR_GetLibraryFilePathname(name, addr);
+ if (!shName) {
+ goto loser;
+ }
+ result = blapi_SHVerifyFile(shName, self);
+
+loser:
+ if (shName != NULL) {
+ PR_Free(shName);
+ }
+
+ return result;
+}
+
+PRBool
+BLAPI_SHVerify(const char *name, PRFuncPtr addr)
+{
+ return blapi_SHVerify(name, addr, PR_FALSE);
+}
+
+PRBool
+BLAPI_SHVerifyFile(const char *shName)
+{
+ return blapi_SHVerifyFile(shName, PR_FALSE);
+}
+
+static PRBool
+blapi_SHVerifyFile(const char *shName, PRBool self)
+{
+ char *checkName = NULL;
+ PRFileDesc *checkFD = NULL;
+ PRFileDesc *shFD = NULL;
+ void *hashcx = NULL;
+ const SECHashObject *hashObj = NULL;
+ SECItem signature = { 0, NULL, 0 };
+ SECItem hash;
+ int bytesRead, offset;
+ SECStatus rv;
+ DSAPublicKey key;
+ int count;
+#ifdef FREEBL_USE_PRELINK
+ int pid = 0;
+#endif
+
+ PRBool result = PR_FALSE; /* if anything goes wrong,
+ * the signature does not verify */
+ unsigned char buf[4096];
+ unsigned char hashBuf[HASH_LENGTH_MAX];
+
+ PORT_Memset(&key, 0, sizeof(key));
+ hash.data = hashBuf;
+ hash.len = sizeof(hashBuf);
+
+ /* If our integrity check was never ran or failed, fail any other
+ * integrity checks to prevent any token going into FIPS mode. */
+ if (!self && (BL_FIPSEntryOK(PR_FALSE) != SECSuccess)) {
+ return PR_FALSE;
+ }
+
+ if (!shName) {
+ goto loser;
+ }
+
+ /* figure out the name of our check file */
+ checkName = mkCheckFileName(shName);
+ if (!checkName) {
+ goto loser;
+ }
+
+ /* open the check File */
+ checkFD = PR_Open(checkName, PR_RDONLY, 0);
+ if (checkFD == NULL) {
+#ifdef DEBUG_SHVERIFY
+ fprintf(stderr, "Failed to open the check file %s: (%d, %d)\n",
+ checkName, (int)PR_GetError(), (int)PR_GetOSError());
+#endif /* DEBUG_SHVERIFY */
+ goto loser;
+ }
+
+ /* read and Verify the headerthe header */
+ bytesRead = PR_Read(checkFD, buf, 12);
+ if (bytesRead != 12) {
+ goto loser;
+ }
+ if ((buf[0] != NSS_SIGN_CHK_MAGIC1) || (buf[1] != NSS_SIGN_CHK_MAGIC2)) {
+ goto loser;
+ }
+ if ((buf[2] != NSS_SIGN_CHK_MAJOR_VERSION) ||
+ (buf[3] < NSS_SIGN_CHK_MINOR_VERSION)) {
+ goto loser;
+ }
+#ifdef notdef
+ if (decodeInt(&buf[8]) != CKK_DSA) {
+ goto loser;
+ }
+#endif
+
+ /* seek past any future header extensions */
+ offset = decodeInt(&buf[4]);
+ if (PR_Seek(checkFD, offset, PR_SEEK_SET) < 0) {
+ goto loser;
+ }
+
+ /* read the key */
+ rv = readItem(checkFD, &key.params.prime);
+ if (rv != SECSuccess) {
+ goto loser;
+ }
+ rv = readItem(checkFD, &key.params.subPrime);
+ if (rv != SECSuccess) {
+ goto loser;
+ }
+ rv = readItem(checkFD, &key.params.base);
+ if (rv != SECSuccess) {
+ goto loser;
+ }
+ rv = readItem(checkFD, &key.publicValue);
+ if (rv != SECSuccess) {
+ goto loser;
+ }
+ /* read the siganture */
+ rv = readItem(checkFD, &signature);
+ if (rv != SECSuccess) {
+ goto loser;
+ }
+
+ /* done with the check file */
+ PR_Close(checkFD);
+ checkFD = NULL;
+
+ hashObj = HASH_GetRawHashObject(PQG_GetHashType(&key.params));
+ if (hashObj == NULL) {
+ goto loser;
+ }
+
+/* open our library file */
+#ifdef FREEBL_USE_PRELINK
+ shFD = bl_OpenUnPrelink(shName, &pid);
+#else
+ shFD = PR_Open(shName, PR_RDONLY, 0);
+#endif
+ if (shFD == NULL) {
+#ifdef DEBUG_SHVERIFY
+ fprintf(stderr, "Failed to open the library file %s: (%d, %d)\n",
+ shName, (int)PR_GetError(), (int)PR_GetOSError());
+#endif /* DEBUG_SHVERIFY */
+ goto loser;
+ }
+
+ /* hash our library file with SHA1 */
+ hashcx = hashObj->create();
+ if (hashcx == NULL) {
+ goto loser;
+ }
+ hashObj->begin(hashcx);
+
+ count = 0;
+ while ((bytesRead = PR_Read(shFD, buf, sizeof(buf))) > 0) {
+ hashObj->update(hashcx, buf, bytesRead);
+ count += bytesRead;
+ }
+#ifdef FREEBL_USE_PRELINK
+ bl_CloseUnPrelink(shFD, pid);
+#else
+ PR_Close(shFD);
+#endif
+ shFD = NULL;
+
+ hashObj->end(hashcx, hash.data, &hash.len, hash.len);
+
+ /* verify the hash against the check file */
+ if (DSA_VerifyDigest(&key, &signature, &hash) == SECSuccess) {
+ result = PR_TRUE;
+ }
+#ifdef DEBUG_SHVERIFY
+ {
+ int i, j;
+ fprintf(stderr, "File %s: %d bytes\n", shName, count);
+ fprintf(stderr, " hash: %d bytes\n", hash.len);
+#define STEP 10
+ for (i = 0; i < hash.len; i += STEP) {
+ fprintf(stderr, " ");
+ for (j = 0; j < STEP && (i + j) < hash.len; j++) {
+ fprintf(stderr, " %02x", hash.data[i + j]);
+ }
+ fprintf(stderr, "\n");
+ }
+ fprintf(stderr, " signature: %d bytes\n", signature.len);
+ for (i = 0; i < signature.len; i += STEP) {
+ fprintf(stderr, " ");
+ for (j = 0; j < STEP && (i + j) < signature.len; j++) {
+ fprintf(stderr, " %02x", signature.data[i + j]);
+ }
+ fprintf(stderr, "\n");
+ }
+ fprintf(stderr, "Verified : %s\n", result ? "TRUE" : "FALSE");
+ }
+#endif /* DEBUG_SHVERIFY */
+
+loser:
+ if (checkName != NULL) {
+ PORT_Free(checkName);
+ }
+ if (checkFD != NULL) {
+ PR_Close(checkFD);
+ }
+ if (shFD != NULL) {
+ PR_Close(shFD);
+ }
+ if (hashcx != NULL) {
+ if (hashObj) {
+ hashObj->destroy(hashcx, PR_TRUE);
+ }
+ }
+ if (signature.data != NULL) {
+ PORT_Free(signature.data);
+ }
+ if (key.params.prime.data != NULL) {
+ PORT_Free(key.params.prime.data);
+ }
+ if (key.params.subPrime.data != NULL) {
+ PORT_Free(key.params.subPrime.data);
+ }
+ if (key.params.base.data != NULL) {
+ PORT_Free(key.params.base.data);
+ }
+ if (key.publicValue.data != NULL) {
+ PORT_Free(key.publicValue.data);
+ }
+
+ return result;
+}
+
+PRBool
+BLAPI_VerifySelf(const char *name)
+{
+ if (name == NULL) {
+ /*
+ * If name is NULL, freebl is statically linked into softoken.
+ * softoken will call BLAPI_SHVerify next to verify itself.
+ */
+ return PR_TRUE;
+ }
+ return blapi_SHVerify(name, (PRFuncPtr)decodeInt, PR_TRUE);
+}