PACKETize and clean up ssl_bytes_to_cipher_list. (38a3cbfb) · Commits · CYBER - Cyber Security / TS 103 523 MSP / ETS / ETS OpenSSL

ssl/s3_srvr.c

+63 −59

Original line number	Diff line number	Diff line
		@@ -164,8 +164,10 @@
		#include <openssl/bn.h>
		#include <openssl/md5.h>

		static STACK_OF(SSL_CIPHER) ssl_bytes_to_cipher_list(SSL s, unsigned char *p,
		int num, STACK_OF(SSL_CIPHER) **skp, int sslv2format);
		static STACK_OF(SSL_CIPHER) ssl_bytes_to_cipher_list(SSL s,
		PACKET *cipher_suites,
		STACK_OF(SSL_CIPHER) **skp,
		int sslv2format, int *al);


		#ifndef OPENSSL_NO_SRP
		@@ -1208,20 +1210,11 @@ int ssl3_get_client_hello(SSL *s)
		}
		}

		if (PACKET_remaining(&cipher_suites) == 0) {
		/* we need at least one cipher */
		al = SSL_AD_ILLEGAL_PARAMETER;
		SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_NO_CIPHERS_SPECIFIED);
		if (ssl_bytes_to_cipher_list(s, &cipher_suites, &(ciphers),
		is_v2_record, &al) == NULL) {
		goto f_err;
		}

		if (ssl_bytes_to_cipher_list(s, PACKET_data(&cipher_suites),
		PACKET_remaining(&cipher_suites),
		&(ciphers), is_v2_record) == NULL) {
		/* TODO(openssl-team): make this alert correctly. */
		goto err;
		}

		/* If it is a hit, check that the cipher is in the list */
		if (s->hit) {
		j = 0;
		@@ -3452,32 +3445,49 @@ err:

		#define SSLV2_CIPHER_LEN 3

		STACK_OF(SSL_CIPHER) ssl_bytes_to_cipher_list(SSL s, unsigned char *p,
		int num,
		STACK_OF(SSL_CIPHER) ssl_bytes_to_cipher_list(SSL s,
		PACKET *cipher_suites,
		STACK_OF(SSL_CIPHER) **skp,
		int sslv2format)
		int sslv2format, int *al
		)
		{
		const SSL_CIPHER *c;
		STACK_OF(SSL_CIPHER) *sk;
		int i, n;
		int n;
		/* 3 = SSLV2_CIPHER_LEN > TLS_CIPHER_LEN = 2. */
		unsigned char cipher[SSLV2_CIPHER_LEN];

		/*
		* Can this ever happen?
		* This method used to check for s->s3, but did so inconsistently.
		*/
		if (s->s3 == NULL) {
		*al = SSL_AD_INTERNAL_ERROR;
		return NULL;
		}

		if (s->s3)
		s->s3->send_connection_binding = 0;

		if(sslv2format) {
		n = SSLV2_CIPHER_LEN;
		} else {
		n = TLS_CIPHER_LEN;
		n = sslv2format ? SSLV2_CIPHER_LEN : TLS_CIPHER_LEN;

		if (PACKET_remaining(cipher_suites) == 0) {
		SSLerr(SSL_F_SSL_BYTES_TO_CIPHER_LIST, SSL_R_NO_CIPHERS_SPECIFIED);
		*al = SSL_AD_ILLEGAL_PARAMETER;
		return NULL;
		}
		if (n == 0 \|\| (num % n) != 0) {

		if (PACKET_remaining(cipher_suites) % n != 0) {
		SSLerr(SSL_F_SSL_BYTES_TO_CIPHER_LIST,
		SSL_R_ERROR_IN_RECEIVED_CIPHER_LIST);
		return (NULL);
		*al = SSL_AD_DECODE_ERROR;
		return NULL;
		}

		if ((skp == NULL) \|\| (*skp == NULL)) {
		sk = sk_SSL_CIPHER_new_null(); /* change perhaps later */
		if(sk == NULL) {
		SSLerr(SSL_F_SSL_BYTES_TO_CIPHER_LIST, ERR_R_MALLOC_FAILURE);
		*al = SSL_AD_INTERNAL_ERROR;
		return NULL;
		}
		} else {
		@@ -3485,28 +3495,33 @@ STACK_OF(SSL_CIPHER) ssl_bytes_to_cipher_list(SSL s, unsigned char *p,
		sk_SSL_CIPHER_zero(sk);
		}

		OPENSSL_free(s->s3->tmp.ciphers_raw);
		s->s3->tmp.ciphers_raw = BUF_memdup(p, num);
		if (s->s3->tmp.ciphers_raw == NULL) {
		SSLerr(SSL_F_SSL_BYTES_TO_CIPHER_LIST, ERR_R_MALLOC_FAILURE);
		if (!PACKET_memdup(cipher_suites, &s->s3->tmp.ciphers_raw,
		&s->s3->tmp.ciphers_rawlen)) {
		*al = SSL_AD_INTERNAL_ERROR;
		goto err;
		}
		s->s3->tmp.ciphers_rawlen = (size_t)num;

		for (i = 0; i < num; i += n) {
		while (PACKET_copy_bytes(cipher_suites, cipher, n)) {
		/*
		* We only support SSLv2 format ciphers in SSLv3+ using a
		* SSLv2 backward compatible ClientHello. In this case the first
		* byte is always 0 for SSLv3 compatible ciphers. Anything else
		* is an SSLv2 cipher and we ignore it
		*/
		if (sslv2format && cipher[0] != '\0')
		continue;

		/* Check for TLS_EMPTY_RENEGOTIATION_INFO_SCSV */
		if (s->s3 && (n != 3 \|\| !p[0]) &&
		(p[n - 2] == ((SSL3_CK_SCSV >> 8) & 0xff)) &&
		(p[n - 1] == (SSL3_CK_SCSV & 0xff))) {
		if ((cipher[n - 2] == ((SSL3_CK_SCSV >> 8) & 0xff)) &&
		(cipher[n - 1] == (SSL3_CK_SCSV & 0xff))) {
		/* SCSV fatal if renegotiating */
		if (s->renegotiate) {
		SSLerr(SSL_F_SSL_BYTES_TO_CIPHER_LIST,
		SSL_R_SCSV_RECEIVED_WHEN_RENEGOTIATING);
		ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
		*al = SSL_AD_HANDSHAKE_FAILURE;
		goto err;
		}
		s->s3->send_connection_binding = 1;
		p += n;
		#ifdef OPENSSL_RI_DEBUG
		fprintf(stderr, "SCSV received by server\n");
		#endif
		@@ -3514,9 +3529,8 @@ STACK_OF(SSL_CIPHER) ssl_bytes_to_cipher_list(SSL s, unsigned char *p,
		}

		/* Check for TLS_FALLBACK_SCSV */
		if ((n != 3 \|\| !p[0]) &&
		(p[n - 2] == ((SSL3_CK_FALLBACK_SCSV >> 8) & 0xff)) &&
		(p[n - 1] == (SSL3_CK_FALLBACK_SCSV & 0xff))) {
		if ((cipher[n - 2] == ((SSL3_CK_FALLBACK_SCSV >> 8) & 0xff)) &&
		(cipher[n - 1] == (SSL3_CK_FALLBACK_SCSV & 0xff))) {
		/*
		* The SCSV indicates that the client previously tried a higher
		* version. Fail if the current version is an unexpected
		@@ -3525,37 +3539,27 @@ STACK_OF(SSL_CIPHER) ssl_bytes_to_cipher_list(SSL s, unsigned char *p,
		if (!SSL_ctrl(s, SSL_CTRL_CHECK_PROTO_VERSION, 0, NULL)) {
		SSLerr(SSL_F_SSL_BYTES_TO_CIPHER_LIST,
		SSL_R_INAPPROPRIATE_FALLBACK);
		if (s->s3)
		ssl3_send_alert(s, SSL3_AL_FATAL,
		SSL_AD_INAPPROPRIATE_FALLBACK);
		*al = SSL_AD_INAPPROPRIATE_FALLBACK;
		goto err;
		}
		p += n;
		continue;
		}

		if(sslv2format) {
		/*
		* We only support SSLv2 format ciphers in SSLv3+ using a
		* SSLv2 backward compatible ClientHello. In this case the first
		* byte is always 0 for SSLv3 compatible ciphers. Anything else
		* is an SSLv2 cipher and we ignore it
		*/
		if(p[0] == 0)
		c = ssl_get_cipher_by_char(s, &p[1]);
		else
		c = NULL;
		} else {
		c = ssl_get_cipher_by_char(s, p);
		}
		p += n;
		/* For SSLv2-compat, ignore leading 0-byte. */
		c = ssl_get_cipher_by_char(s, sslv2format ? &cipher[1] : cipher);
		if (c != NULL) {
		if (!sk_SSL_CIPHER_push(sk, c)) {
		SSLerr(SSL_F_SSL_BYTES_TO_CIPHER_LIST, ERR_R_MALLOC_FAILURE);
		*al = SSL_AD_INTERNAL_ERROR;
		goto err;
		}
		}
		}
		if (PACKET_remaining(cipher_suites) > 0) {
		*al = SSL_AD_INTERNAL_ERROR;
		SSLerr(SSL_F_SSL_BYTES_TO_CIPHER_LIST, ERR_R_INTERNAL_ERROR);
		goto err;
		}

		if (skp != NULL)
		*skp = sk;
		@@ -3563,5 +3567,5 @@ STACK_OF(SSL_CIPHER) ssl_bytes_to_cipher_list(SSL s, unsigned char *p,
		err:
		if ((skp == NULL) \|\| (*skp == NULL))
		sk_SSL_CIPHER_free(sk);
		return (NULL);
		return NULL;
		}