static int ssl23_client_hello(SSL *s) { unsigned char *buf; unsigned char *p,*d; int i; unsigned long l; int version = 0, version_major, version_minor; int ret; unsigned long mask, options = s->options; /* * SSL_OP_NO_X disables all protocols above X *if* there are * some protocols below X enabled. This is required in order * to maintain "version capability" vector contiguous. So * that if application wants to disable TLS1.0 in favour of * TLS1>=1, it would be insufficient to pass SSL_NO_TLSv1, the * answer is SSL_OP_NO_TLSv1|SSL_OP_NO_SSLv3|SSL_OP_NO_SSLv2. */ mask = SSL_OP_NO_TLSv1_1|SSL_OP_NO_TLSv1|SSL_OP_NO_SSLv3; version = TLS1_2_VERSION; if ((options & SSL_OP_NO_TLSv1_2) && (options & mask) != mask) version = TLS1_1_VERSION; mask &= ~SSL_OP_NO_TLSv1_1; if ((options & SSL_OP_NO_TLSv1_1) && (options & mask) != mask) version = TLS1_VERSION; mask &= ~SSL_OP_NO_TLSv1; if ((options & SSL_OP_NO_TLSv1) && (options & mask) != mask) version = SSL3_VERSION; mask &= ~SSL_OP_NO_SSLv3; buf=(unsigned char *)s->init_buf->data; if (s->state == SSL23_ST_CW_CLNT_HELLO_A) { /* Check if the session is resumable. If not, drop it. */ if (s->session != NULL) { if (s->session->ssl_version > version || s->session->session_id_length == 0 || s->session->not_resumable) { SSL_SESSION_free(s->session); s->session = NULL; } } p=s->s3->client_random; if (ssl_fill_hello_random(s, 0, p, SSL3_RANDOM_SIZE) <= 0) return -1; if (version == TLS1_2_VERSION) { version_major = TLS1_2_VERSION_MAJOR; version_minor = TLS1_2_VERSION_MINOR; } else if (version == TLS1_1_VERSION) { version_major = TLS1_1_VERSION_MAJOR; version_minor = TLS1_1_VERSION_MINOR; } else if (version == TLS1_VERSION) { version_major = TLS1_VERSION_MAJOR; version_minor = TLS1_VERSION_MINOR; } else if (version == SSL3_VERSION) { version_major = SSL3_VERSION_MAJOR; version_minor = SSL3_VERSION_MINOR; } else if (version == SSL2_VERSION) { version_major = SSL2_VERSION_MAJOR; version_minor = SSL2_VERSION_MINOR; } else { OPENSSL_PUT_ERROR(SSL, ssl23_client_hello, SSL_R_NO_PROTOCOLS_AVAILABLE); return(-1); } s->client_version = version; /* create Client Hello in SSL 3.0/TLS 1.0 format */ /* do the record header (5 bytes) and handshake message * header (4 bytes) last. Note: the final argument to * ssl_add_clienthello_tlsext below depends on the size * of this prefix. */ d = p = &(buf[9]); *(p++) = version_major; *(p++) = version_minor; /* Random stuff */ memcpy(p, s->s3->client_random, SSL3_RANDOM_SIZE); p += SSL3_RANDOM_SIZE; /* Session ID */ if (s->new_session || s->session == NULL) i=0; else i=s->session->session_id_length; *(p++)=i; if (i != 0) { if (i > (int)sizeof(s->session->session_id)) { OPENSSL_PUT_ERROR(SSL, ssl23_client_hello, ERR_R_INTERNAL_ERROR); return -1; } memcpy(p,s->session->session_id,i); p+=i; } /* Ciphers supported (using SSL 3.0/TLS 1.0 format) */ i = ssl_cipher_list_to_bytes(s, SSL_get_ciphers(s), &p[2]); if (i == 0) { OPENSSL_PUT_ERROR(SSL, ssl23_client_hello, SSL_R_NO_CIPHERS_AVAILABLE); return -1; } s2n(i,p); p+=i; /* COMPRESSION */ *(p++)=1; *(p++)=0; /* Add the NULL method */ /* TLS extensions*/ if (ssl_prepare_clienthello_tlsext(s) <= 0) { OPENSSL_PUT_ERROR(SSL, ssl23_client_hello, SSL_R_CLIENTHELLO_TLSEXT); return -1; } /* The buffer includes the 5 byte record header, so * subtract it to compute hlen for * ssl_add_clienthello_tlsext. */ if ((p = ssl_add_clienthello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH, p-buf-5)) == NULL) { OPENSSL_PUT_ERROR(SSL, ssl23_client_hello, ERR_R_INTERNAL_ERROR); return -1; } l = p-d; /* fill in 4-byte handshake header */ d=&(buf[5]); *(d++)=SSL3_MT_CLIENT_HELLO; l2n3(l,d); l += 4; if (l > SSL3_RT_MAX_PLAIN_LENGTH) { OPENSSL_PUT_ERROR(SSL, ssl23_client_hello, ERR_R_INTERNAL_ERROR); return -1; } /* fill in 5-byte record header */ d=buf; *(d++) = SSL3_RT_HANDSHAKE; *(d++) = version_major; /* Some servers hang if we use long client hellos * and a record number > TLS 1.0. */ if (TLS1_get_client_version(s) > TLS1_VERSION) *(d++) = 1; else *(d++) = version_minor; s2n((int)l,d); /* number of bytes to write */ s->init_num=p-buf; s->init_off=0; ssl3_finish_mac(s,&(buf[5]), s->init_num - 5); s->state=SSL23_ST_CW_CLNT_HELLO_B; s->init_off=0; } /* SSL3_ST_CW_CLNT_HELLO_B */ ret = ssl23_write_bytes(s); if ((ret >= 2) && s->msg_callback) { /* Client Hello has been sent; tell msg_callback */ s->msg_callback(1, version, SSL3_RT_HEADER, s->init_buf->data, 5, s, s->msg_callback_arg); s->msg_callback(1, version, SSL3_RT_HANDSHAKE, s->init_buf->data+5, ret-5, s, s->msg_callback_arg); } return ret; }
*(d++) = version_minor; s2n((int)l,d); /* number of bytes to write */ s->init_num=p-buf; s->init_off=0; ssl3_finish_mac(s,&(buf[5]), s->init_num - 5); } s->state=SSL23_ST_CW_CLNT_HELLO_B; s->init_off=0; } /* SSL3_ST_CW_CLNT_HELLO_B */ ret = ssl23_write_bytes(s); if ((ret >= 2) && s->msg_callback) { /* Client Hello has been sent; tell msg_callback */ if (ssl2_compat) s->msg_callback(1, SSL2_VERSION, 0, s->init_buf->data+2, ret-2, s, s->msg_callback_arg); else s->msg_callback(1, version, SSL3_RT_HANDSHAKE, s->init_buf->data+5, ret-5, s, s->msg_callback_arg); } return ret; } static int ssl23_get_server_hello(SSL *s)
static int ssl23_client_hello(SSL *s) { unsigned char *buf; unsigned char *p, *d; int i; unsigned long l; int version = 0, version_major, version_minor; int ret; unsigned long mask, options = s->options; /* * SSL_OP_NO_X disables all protocols above X *if* there are * some protocols below X enabled. This is required in order * to maintain "version capability" vector contiguous. So * that if application wants to disable TLS1.0 in favour of * TLS1>=1, it would be insufficient to pass SSL_NO_TLSv1, the * answer is SSL_OP_NO_TLSv1|SSL_OP_NO_SSLv3|SSL_OP_NO_SSLv2. */ mask = SSL_OP_NO_TLSv1_1|SSL_OP_NO_TLSv1|SSL_OP_NO_SSLv3; version = TLS1_2_VERSION; if ((options & SSL_OP_NO_TLSv1_2) && (options & mask) != mask) version = TLS1_1_VERSION; mask &= ~SSL_OP_NO_TLSv1_1; if ((options & SSL_OP_NO_TLSv1_1) && (options & mask) != mask) version = TLS1_VERSION; mask &= ~SSL_OP_NO_TLSv1; if ((options & SSL_OP_NO_TLSv1) && (options & mask) != mask) version = SSL3_VERSION; mask &= ~SSL_OP_NO_SSLv3; buf = (unsigned char *)s->init_buf->data; if (s->state == SSL23_ST_CW_CLNT_HELLO_A) { p = s->s3->client_random; RAND_pseudo_bytes(p, SSL3_RANDOM_SIZE); if (version == TLS1_2_VERSION) { version_major = TLS1_2_VERSION_MAJOR; version_minor = TLS1_2_VERSION_MINOR; } else if (version == TLS1_1_VERSION) { version_major = TLS1_1_VERSION_MAJOR; version_minor = TLS1_1_VERSION_MINOR; } else if (version == TLS1_VERSION) { version_major = TLS1_VERSION_MAJOR; version_minor = TLS1_VERSION_MINOR; } else if (version == SSL3_VERSION) { version_major = SSL3_VERSION_MAJOR; version_minor = SSL3_VERSION_MINOR; } else { SSLerr(SSL_F_SSL23_CLIENT_HELLO, SSL_R_NO_PROTOCOLS_AVAILABLE); return (-1); } s->client_version = version; /* create Client Hello in SSL 3.0/TLS 1.0 format */ /* * Do the record header (5 bytes) and handshake * message header (4 bytes) last */ d = p = &(buf[9]); *(p++) = version_major; *(p++) = version_minor; /* Random stuff */ memcpy(p, s->s3->client_random, SSL3_RANDOM_SIZE); p += SSL3_RANDOM_SIZE; /* Session ID (zero since there is no reuse) */ *(p++) = 0; /* Ciphers supported (using SSL 3.0/TLS 1.0 format) */ i = ssl_cipher_list_to_bytes(s, SSL_get_ciphers(s), &(p[2]), ssl3_put_cipher_by_char); if (i == 0) { SSLerr(SSL_F_SSL23_CLIENT_HELLO, SSL_R_NO_CIPHERS_AVAILABLE); return -1; } #ifdef OPENSSL_MAX_TLS1_2_CIPHER_LENGTH /* * Some servers hang if client hello > 256 bytes * as hack workaround chop number of supported ciphers * to keep it well below this if we use TLS v1.2 */ if (TLS1_get_version(s) >= TLS1_2_VERSION && i > OPENSSL_MAX_TLS1_2_CIPHER_LENGTH) i = OPENSSL_MAX_TLS1_2_CIPHER_LENGTH & ~1; #endif s2n(i, p); p += i; /* add in (no) COMPRESSION */ *(p++) = 1; /* Add the NULL method */ *(p++) = 0; /* TLS extensions*/ if (ssl_prepare_clienthello_tlsext(s) <= 0) { SSLerr(SSL_F_SSL23_CLIENT_HELLO, SSL_R_CLIENTHELLO_TLSEXT); return -1; } if ((p = ssl_add_clienthello_tlsext(s, p, buf + SSL3_RT_MAX_PLAIN_LENGTH)) == NULL) { SSLerr(SSL_F_SSL23_CLIENT_HELLO, ERR_R_INTERNAL_ERROR); return -1; } l = p - d; /* fill in 4-byte handshake header */ d = &(buf[5]); *(d++) = SSL3_MT_CLIENT_HELLO; l2n3(l, d); l += 4; if (l > SSL3_RT_MAX_PLAIN_LENGTH) { SSLerr(SSL_F_SSL23_CLIENT_HELLO, ERR_R_INTERNAL_ERROR); return -1; } /* fill in 5-byte record header */ d = buf; *(d++) = SSL3_RT_HANDSHAKE; *(d++) = version_major; /* * Some servers hang if we use long client hellos * and a record number > TLS 1.0. */ if (TLS1_get_client_version(s) > TLS1_VERSION) *(d++) = 1; else *(d++) = version_minor; s2n((int)l, d); /* number of bytes to write */ s->init_num = p - buf; s->init_off = 0; ssl3_finish_mac(s, &(buf[5]), s->init_num - 5); s->state = SSL23_ST_CW_CLNT_HELLO_B; s->init_off = 0; } /* SSL3_ST_CW_CLNT_HELLO_B */ ret = ssl23_write_bytes(s); if ((ret >= 2) && s->msg_callback) { /* Client Hello has been sent; tell msg_callback */ s->msg_callback(1, version, SSL3_RT_HANDSHAKE, s->init_buf->data + 5, ret - 5, s, s->msg_callback_arg); } return ret; }