Prevent cross-site forgery attacks on lukemftpd(8) due to splitting

long commands into multiple requests. [09:01]

Fix incorrect OpenSSL checks for malformed signatures due to invalid
check of return value from EVP_VerifyFinal(), DSA_verify, and
DSA_do_verify. [09:02]

Security:	FreeBSD-SA-09:01.lukemftpd
Security:	FreeBSD-SA-09:02.openssl
Obtained from:	NetBSD [SA-09:01]
Obtained from:	OpenSSL Project [SA-09:02]
Approved by:	so (simon)
This commit is contained in:
Simon L. B. Nielsen 2009-01-07 20:17:55 +00:00
parent 7251cf2c6c
commit 8978d9e7ef
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=186872
12 changed files with 52 additions and 24 deletions

View File

@ -139,7 +139,7 @@ void feat(void);
void format_path(char *, const char *);
int ftpd_pclose(FILE *);
FILE *ftpd_popen(char *[], const char *, int);
char *getline(char *, int, FILE *);
int getline(char *, int, FILE *);
void init_curclass(void);
void logxfer(const char *, off_t, const char *, const char *,
const struct timeval *, const char *);

View File

@ -1363,8 +1363,12 @@ lookup(struct tab *p, const char *cmd)
/*
* getline - a hacked up version of fgets to ignore TELNET escape codes.
* `s' is the buffer to read into.
* `n' is the 1 less than the size of the buffer, to allow trailing NUL
* `iop' is the FILE to read from.
* Returns 0 on success, -1 on EOF, -2 if the command was too long.
*/
char *
int
getline(char *s, int n, FILE *iop)
{
int c;
@ -1379,7 +1383,7 @@ getline(char *s, int n, FILE *iop)
if (ftpd_debug)
syslog(LOG_DEBUG, "command: %s", s);
tmpline[0] = '\0';
return(s);
return(0);
}
if (c == 0)
tmpline[0] = '\0';
@ -1418,11 +1422,25 @@ getline(char *s, int n, FILE *iop)
}
}
*cs++ = c;
if (--n <= 0 || c == '\n')
if (--n <= 0) {
/*
* If command doesn't fit into buffer, discard the
* rest of the command and indicate truncation.
* This prevents the command to be split up into
* multiple commands.
*/
if (ftpd_debug)
syslog(LOG_DEBUG,
"command too long, last char: %d", c);
while (c != '\n' && (c = getc(iop)) != EOF)
continue;
return (-2);
}
if (c == '\n')
break;
}
if (c == EOF && cs == s)
return (NULL);
return (-1);
*cs++ = '\0';
if (ftpd_debug) {
if ((curclass.type != CLASS_GUEST &&
@ -1444,7 +1462,7 @@ getline(char *s, int n, FILE *iop)
syslog(LOG_DEBUG, "command: %.*s", len, s);
}
}
return (s);
return (0);
}
void
@ -1458,15 +1476,20 @@ ftp_handle_line(char *cp)
void
ftp_loop(void)
{
int ret;
while (1) {
(void) alarm(curclass.timeout);
if (getline(cbuf, sizeof(cbuf)-1, stdin) == NULL) {
ret = getline(cbuf, sizeof(cbuf)-1, stdin);
(void) alarm(0);
if (ret == -1) {
reply(221, "You could at least say goodbye.");
dologout(0);
} else if (ret == -2) {
reply(500, "Command too long.");
} else {
ftp_handle_line(cbuf);
}
(void) alarm(0);
ftp_handle_line(cbuf);
}
/*NOTREACHED*/
}

View File

@ -1,4 +1,4 @@
/* $NetBSD: ftpd.c,v 1.176 2006/05/09 20:18:06 mrg Exp $ */
/* $NetBSD: ftpd.c,v 1.187 2008/09/13 03:30:35 lukem Exp $ */
/*
* Copyright (c) 1997-2004 The NetBSD Foundation, Inc.
@ -2896,6 +2896,7 @@ static int
handleoobcmd()
{
char *cp;
int ret;
if (!urgflag)
return (0);
@ -2904,9 +2905,14 @@ handleoobcmd()
if (!transflag)
return (0);
cp = tmpline;
if (getline(cp, sizeof(tmpline), stdin) == NULL) {
ret = getline(cp, sizeof(tmpline)-1, stdin);
if (ret == -1) {
reply(221, "You could at least say goodbye.");
dologout(0);
} else if (ret == -2) {
/* Ignore truncated command */
/* XXX: abort xfer with "500 command too long", & return 1 ? */
return 0;
}
/*
* Manually parse OOB commands, because we can't

View File

@ -2038,7 +2038,7 @@ int MAIN(int argc, char **argv)
{
ret=RSA_verify(NID_md5_sha1, buf,36, buf2,
rsa_num, rsa_key[j]);
if (ret == 0)
if (ret <= 0)
{
BIO_printf(bio_err,
"RSA verify failure\n");

View File

@ -285,7 +285,7 @@ int MAIN(int argc, char **argv)
pkey = NETSCAPE_SPKI_get_pubkey(spki);
if(verify) {
i = NETSCAPE_SPKI_verify(spki, pkey);
if(i) BIO_printf(bio_err, "Signature OK\n");
if (i > 0) BIO_printf(bio_err, "Signature OK\n");
else {
BIO_printf(bio_err, "Signature Failure\n");
ERR_print_errors(bio_err);

View File

@ -266,7 +266,7 @@ static int check(X509_STORE *ctx, char *file, STACK_OF(X509) *uchain, STACK_OF(X
ret=0;
end:
if (i)
if (i > 0)
{
fprintf(stdout,"OK\n");
ret=1;
@ -367,4 +367,3 @@ static int MS_CALLBACK cb(int ok, X509_STORE_CTX *ctx)
ERR_clear_error();
return(ok);
}

View File

@ -1144,7 +1144,7 @@ static int x509_certify(X509_STORE *ctx, char *CAfile, const EVP_MD *digest,
/* NOTE: this certificate can/should be self signed, unless it was
* a certificate request in which case it is not. */
X509_STORE_CTX_set_cert(&xsc,x);
if (!reqfile && !X509_verify_cert(&xsc))
if (!reqfile && X509_verify_cert(&xsc) <= 0)
goto end;
if (!X509_check_private_key(xca,pkey))

View File

@ -1044,7 +1044,7 @@ int ssl2_set_certificate(SSL *s, int type, int len, const unsigned char *data)
i=ssl_verify_cert_chain(s,sk);
if ((s->verify_mode != SSL_VERIFY_NONE) && (!i))
if ((s->verify_mode != SSL_VERIFY_NONE) && (i <= 0))
{
SSLerr(SSL_F_SSL2_SET_CERTIFICATE,SSL_R_CERTIFICATE_VERIFY_FAILED);
goto err;

View File

@ -1054,7 +1054,7 @@ static int request_certificate(SSL *s)
i=ssl_verify_cert_chain(s,sk);
if (i) /* we like the packet, now check the chksum */
if (i > 0) /* we like the packet, now check the chksum */
{
EVP_MD_CTX ctx;
EVP_PKEY *pkey=NULL;
@ -1083,7 +1083,7 @@ static int request_certificate(SSL *s)
EVP_PKEY_free(pkey);
EVP_MD_CTX_cleanup(&ctx);
if (i)
if (i > 0)
{
if (s->session->peer != NULL)
X509_free(s->session->peer);

View File

@ -883,7 +883,7 @@ int ssl3_get_server_certificate(SSL *s)
}
i=ssl_verify_cert_chain(s,sk);
if ((s->verify_mode != SSL_VERIFY_NONE) && (!i)
if ((s->verify_mode != SSL_VERIFY_NONE) && (i <= 0)
#ifndef OPENSSL_NO_KRB5
&& (s->s3->tmp.new_cipher->algorithms & (SSL_MKEY_MASK|SSL_AUTH_MASK))
!= (SSL_aKRB5|SSL_kKRB5)
@ -1368,7 +1368,7 @@ int ssl3_get_key_exchange(SSL *s)
EVP_VerifyUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
EVP_VerifyUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
EVP_VerifyUpdate(&md_ctx,param,param_len);
if (!EVP_VerifyFinal(&md_ctx,p,(int)n,pkey))
if (EVP_VerifyFinal(&md_ctx,p,(int)n,pkey) <= 0)
{
/* bad signature */
al=SSL_AD_DECRYPT_ERROR;
@ -1386,7 +1386,7 @@ int ssl3_get_key_exchange(SSL *s)
EVP_VerifyUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
EVP_VerifyUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
EVP_VerifyUpdate(&md_ctx,param,param_len);
if (!EVP_VerifyFinal(&md_ctx,p,(int)n,pkey))
if (EVP_VerifyFinal(&md_ctx,p,(int)n,pkey) <= 0)
{
/* bad signature */
al=SSL_AD_DECRYPT_ERROR;

View File

@ -2481,7 +2481,7 @@ int ssl3_get_client_certificate(SSL *s)
else
{
i=ssl_verify_cert_chain(s,sk);
if (!i)
if (i <= 0)
{
al=ssl_verify_alarm_type(s->verify_result);
SSLerr(SSL_F_SSL3_GET_CLIENT_CERTIFICATE,SSL_R_NO_CERTIFICATE_RETURNED);

View File

@ -2072,7 +2072,7 @@ static int MS_CALLBACK app_verify_callback(X509_STORE_CTX *ctx, void *arg)
if (cb_arg->proxy_auth)
{
if (ok)
if (ok > 0)
{
const char *cond_end = NULL;