/*************************************************************************** * _ _ ____ _ * Project ___| | | | _ \| | * / __| | | | |_) | | * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * * Copyright (C) 1998 - 2015, Daniel Stenberg, , et al. * * This software is licensed as described in the file COPYING, which * you should have received as part of this distribution. The terms * are also available at https://curl.haxx.se/docs/copyright.html. * * You may opt to use, copy, modify, merge, publish, distribute and/or sell * copies of the Software, and permit persons to whom the Software is * furnished to do so, under the terms of the COPYING file. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ***************************************************************************/ /* This file is for implementing all "generic" SSL functions that all libcurl internals should use. It is then responsible for calling the proper "backend" function. SSL-functions in libcurl should call functions in this source file, and not to any specific SSL-layer. Curl_ssl_ - prefix for generic ones Curl_ossl_ - prefix for OpenSSL ones Curl_gtls_ - prefix for GnuTLS ones Curl_nss_ - prefix for NSS ones Curl_gskit_ - prefix for GSKit ones Curl_polarssl_ - prefix for PolarSSL ones Curl_cyassl_ - prefix for CyaSSL ones Curl_schannel_ - prefix for Schannel SSPI ones Curl_darwinssl_ - prefix for SecureTransport (Darwin) ones Note that this source code uses curlssl_* functions, and they are all defines/macros #defined by the lib-specific header files. "SSL/TLS Strong Encryption: An Introduction" https://httpd.apache.org/docs/2.0/ssl/ssl_intro.html */ #include "curl_setup.h" #ifdef HAVE_SYS_TYPES_H #include #endif #ifdef HAVE_SYS_STAT_H #include #endif #ifdef HAVE_FCNTL_H #include #endif #include "urldata.h" #include "vtls.h" /* generic SSL protos etc */ #include "slist.h" #include "sendf.h" #include "rawstr.h" #include "url.h" #include "progress.h" #include "share.h" #include "timeval.h" #include "curl_md5.h" #include "warnless.h" #include "curl_base64.h" #include "curl_printf.h" /* The last #include files should be: */ #include "curl_memory.h" #include "memdebug.h" /* convenience macro to check if this handle is using a shared SSL session */ #define SSLSESSION_SHARED(data) (data->share && \ (data->share->specifier & \ (1<version == needle->version) && (data->verifypeer == needle->verifypeer) && (data->verifyhost == needle->verifyhost) && safe_strequal(data->CApath, needle->CApath) && safe_strequal(data->CAfile, needle->CAfile) && safe_strequal(data->random_file, needle->random_file) && safe_strequal(data->egdsocket, needle->egdsocket) && safe_strequal(data->cipher_list, needle->cipher_list)) return TRUE; return FALSE; } bool Curl_clone_ssl_config(struct ssl_config_data *source, struct ssl_config_data *dest) { dest->sessionid = source->sessionid; dest->verifyhost = source->verifyhost; dest->verifypeer = source->verifypeer; dest->version = source->version; if(source->CAfile) { dest->CAfile = strdup(source->CAfile); if(!dest->CAfile) return FALSE; } else dest->CAfile = NULL; if(source->CApath) { dest->CApath = strdup(source->CApath); if(!dest->CApath) return FALSE; } else dest->CApath = NULL; if(source->cipher_list) { dest->cipher_list = strdup(source->cipher_list); if(!dest->cipher_list) return FALSE; } else dest->cipher_list = NULL; if(source->egdsocket) { dest->egdsocket = strdup(source->egdsocket); if(!dest->egdsocket) return FALSE; } else dest->egdsocket = NULL; if(source->random_file) { dest->random_file = strdup(source->random_file); if(!dest->random_file) return FALSE; } else dest->random_file = NULL; return TRUE; } void Curl_free_ssl_config(struct ssl_config_data* sslc) { Curl_safefree(sslc->CAfile); Curl_safefree(sslc->CApath); Curl_safefree(sslc->cipher_list); Curl_safefree(sslc->egdsocket); Curl_safefree(sslc->random_file); } /* * Curl_rand() returns a random unsigned integer, 32bit. * * This non-SSL function is put here only because this file is the only one * with knowledge of what the underlying SSL libraries provide in terms of * randomizers. * * NOTE: 'data' may be passed in as NULL when coming from external API without * easy handle! * */ unsigned int Curl_rand(struct SessionHandle *data) { unsigned int r = 0; static unsigned int randseed; static bool seeded = FALSE; #ifdef CURLDEBUG char *force_entropy = getenv("CURL_ENTROPY"); if(force_entropy) { if(!seeded) { size_t elen = strlen(force_entropy); size_t clen = sizeof(randseed); size_t min = elen < clen ? elen : clen; memcpy((char *)&randseed, force_entropy, min); seeded = TRUE; } else randseed++; return randseed; } #endif /* data may be NULL! */ if(!Curl_ssl_random(data, (unsigned char *)&r, sizeof(r))) return r; /* If Curl_ssl_random() returns non-zero it couldn't offer randomness and we instead perform a "best effort" */ #ifdef RANDOM_FILE if(!seeded) { /* if there's a random file to read a seed from, use it */ int fd = open(RANDOM_FILE, O_RDONLY); if(fd > -1) { /* read random data into the randseed variable */ ssize_t nread = read(fd, &randseed, sizeof(randseed)); if(nread == sizeof(randseed)) seeded = TRUE; close(fd); } } #endif if(!seeded) { struct timeval now = curlx_tvnow(); infof(data, "WARNING: Using weak random seed\n"); randseed += (unsigned int)now.tv_usec + (unsigned int)now.tv_sec; randseed = randseed * 1103515245 + 12345; randseed = randseed * 1103515245 + 12345; randseed = randseed * 1103515245 + 12345; seeded = TRUE; } /* Return an unsigned 32-bit pseudo-random number. */ r = randseed = randseed * 1103515245 + 12345; return (r << 16) | ((r >> 16) & 0xFFFF); } int Curl_ssl_backend(void) { return (int)CURL_SSL_BACKEND; } #ifdef USE_SSL /* "global" init done? */ static bool init_ssl=FALSE; /** * Global SSL init * * @retval 0 error initializing SSL * @retval 1 SSL initialized successfully */ int Curl_ssl_init(void) { /* make sure this is only done once */ if(init_ssl) return 1; init_ssl = TRUE; /* never again */ return curlssl_init(); } /* Global cleanup */ void Curl_ssl_cleanup(void) { if(init_ssl) { /* only cleanup if we did a previous init */ curlssl_cleanup(); init_ssl = FALSE; } } static bool ssl_prefs_check(struct SessionHandle *data) { /* check for CURLOPT_SSLVERSION invalid parameter value */ if((data->set.ssl.version < 0) || (data->set.ssl.version >= CURL_SSLVERSION_LAST)) { failf(data, "Unrecognized parameter value passed via CURLOPT_SSLVERSION"); return FALSE; } return TRUE; } CURLcode Curl_ssl_connect(struct connectdata *conn, int sockindex) { CURLcode result; if(!ssl_prefs_check(conn->data)) return CURLE_SSL_CONNECT_ERROR; /* mark this is being ssl-enabled from here on. */ conn->ssl[sockindex].use = TRUE; conn->ssl[sockindex].state = ssl_connection_negotiating; result = curlssl_connect(conn, sockindex); if(!result) Curl_pgrsTime(conn->data, TIMER_APPCONNECT); /* SSL is connected */ return result; } CURLcode Curl_ssl_connect_nonblocking(struct connectdata *conn, int sockindex, bool *done) { CURLcode result; if(!ssl_prefs_check(conn->data)) return CURLE_SSL_CONNECT_ERROR; /* mark this is being ssl requested from here on. */ conn->ssl[sockindex].use = TRUE; #ifdef curlssl_connect_nonblocking result = curlssl_connect_nonblocking(conn, sockindex, done); #else *done = TRUE; /* fallback to BLOCKING */ result = curlssl_connect(conn, sockindex); #endif /* non-blocking connect support */ if(!result && *done) Curl_pgrsTime(conn->data, TIMER_APPCONNECT); /* SSL is connected */ return result; } /* * Check if there's a session ID for the given connection in the cache, and if * there's one suitable, it is provided. Returns TRUE when no entry matched. */ bool Curl_ssl_getsessionid(struct connectdata *conn, void **ssl_sessionid, size_t *idsize) /* set 0 if unknown */ { struct curl_ssl_session *check; struct SessionHandle *data = conn->data; size_t i; long *general_age; bool no_match = TRUE; *ssl_sessionid = NULL; if(!conn->ssl_config.sessionid) /* session ID re-use is disabled */ return TRUE; /* Lock if shared */ if(SSLSESSION_SHARED(data)) { Curl_share_lock(data, CURL_LOCK_DATA_SSL_SESSION, CURL_LOCK_ACCESS_SINGLE); general_age = &data->share->sessionage; } else general_age = &data->state.sessionage; for(i = 0; i < data->set.ssl.max_ssl_sessions; i++) { check = &data->state.session[i]; if(!check->sessionid) /* not session ID means blank entry */ continue; if(Curl_raw_equal(conn->host.name, check->name) && (conn->remote_port == check->remote_port) && Curl_ssl_config_matches(&conn->ssl_config, &check->ssl_config)) { /* yes, we have a session ID! */ (*general_age)++; /* increase general age */ check->age = *general_age; /* set this as used in this age */ *ssl_sessionid = check->sessionid; if(idsize) *idsize = check->idsize; no_match = FALSE; break; } } /* Unlock */ if(SSLSESSION_SHARED(data)) Curl_share_unlock(data, CURL_LOCK_DATA_SSL_SESSION); return no_match; } /* * Kill a single session ID entry in the cache. */ void Curl_ssl_kill_session(struct curl_ssl_session *session) { if(session->sessionid) { /* defensive check */ /* free the ID the SSL-layer specific way */ curlssl_session_free(session->sessionid); session->sessionid = NULL; session->age = 0; /* fresh */ Curl_free_ssl_config(&session->ssl_config); Curl_safefree(session->name); } } /* * Delete the given session ID from the cache. */ void Curl_ssl_delsessionid(struct connectdata *conn, void *ssl_sessionid) { size_t i; struct SessionHandle *data=conn->data; if(SSLSESSION_SHARED(data)) Curl_share_lock(data, CURL_LOCK_DATA_SSL_SESSION, CURL_LOCK_ACCESS_SINGLE); for(i = 0; i < data->set.ssl.max_ssl_sessions; i++) { struct curl_ssl_session *check = &data->state.session[i]; if(check->sessionid == ssl_sessionid) { Curl_ssl_kill_session(check); break; } } if(SSLSESSION_SHARED(data)) Curl_share_unlock(data, CURL_LOCK_DATA_SSL_SESSION); } /* * Store session id in the session cache. The ID passed on to this function * must already have been extracted and allocated the proper way for the SSL * layer. Curl_XXXX_session_free() will be called to free/kill the session ID * later on. */ CURLcode Curl_ssl_addsessionid(struct connectdata *conn, void *ssl_sessionid, size_t idsize) { size_t i; struct SessionHandle *data=conn->data; /* the mother of all structs */ struct curl_ssl_session *store = &data->state.session[0]; long oldest_age=data->state.session[0].age; /* zero if unused */ char *clone_host; long *general_age; /* Even though session ID re-use might be disabled, that only disables USING IT. We still store it here in case the re-using is again enabled for an upcoming transfer */ clone_host = strdup(conn->host.name); if(!clone_host) return CURLE_OUT_OF_MEMORY; /* bail out */ /* Now we should add the session ID and the host name to the cache, (remove the oldest if necessary) */ /* If using shared SSL session, lock! */ if(SSLSESSION_SHARED(data)) { Curl_share_lock(data, CURL_LOCK_DATA_SSL_SESSION, CURL_LOCK_ACCESS_SINGLE); general_age = &data->share->sessionage; } else { general_age = &data->state.sessionage; } /* find an empty slot for us, or find the oldest */ for(i = 1; (i < data->set.ssl.max_ssl_sessions) && data->state.session[i].sessionid; i++) { if(data->state.session[i].age < oldest_age) { oldest_age = data->state.session[i].age; store = &data->state.session[i]; } } if(i == data->set.ssl.max_ssl_sessions) /* cache is full, we must "kill" the oldest entry! */ Curl_ssl_kill_session(store); else store = &data->state.session[i]; /* use this slot */ /* now init the session struct wisely */ store->sessionid = ssl_sessionid; store->idsize = idsize; store->age = *general_age; /* set current age */ /* free it if there's one already present */ free(store->name); store->name = clone_host; /* clone host name */ store->remote_port = conn->remote_port; /* port number */ /* Unlock */ if(SSLSESSION_SHARED(data)) Curl_share_unlock(data, CURL_LOCK_DATA_SSL_SESSION); if(!Curl_clone_ssl_config(&conn->ssl_config, &store->ssl_config)) { store->sessionid = NULL; /* let caller free sessionid */ free(clone_host); return CURLE_OUT_OF_MEMORY; } return CURLE_OK; } void Curl_ssl_close_all(struct SessionHandle *data) { size_t i; /* kill the session ID cache if not shared */ if(data->state.session && !SSLSESSION_SHARED(data)) { for(i = 0; i < data->set.ssl.max_ssl_sessions; i++) /* the single-killer function handles empty table slots */ Curl_ssl_kill_session(&data->state.session[i]); /* free the cache data */ Curl_safefree(data->state.session); } curlssl_close_all(data); } void Curl_ssl_close(struct connectdata *conn, int sockindex) { DEBUGASSERT((sockindex <= 1) && (sockindex >= -1)); curlssl_close(conn, sockindex); } CURLcode Curl_ssl_shutdown(struct connectdata *conn, int sockindex) { if(curlssl_shutdown(conn, sockindex)) return CURLE_SSL_SHUTDOWN_FAILED; conn->ssl[sockindex].use = FALSE; /* get back to ordinary socket usage */ conn->ssl[sockindex].state = ssl_connection_none; conn->recv[sockindex] = Curl_recv_plain; conn->send[sockindex] = Curl_send_plain; return CURLE_OK; } /* Selects an SSL crypto engine */ CURLcode Curl_ssl_set_engine(struct SessionHandle *data, const char *engine) { return curlssl_set_engine(data, engine); } /* Selects the default SSL crypto engine */ CURLcode Curl_ssl_set_engine_default(struct SessionHandle *data) { return curlssl_set_engine_default(data); } /* Return list of OpenSSL crypto engine names. */ struct curl_slist *Curl_ssl_engines_list(struct SessionHandle *data) { return curlssl_engines_list(data); } /* * This sets up a session ID cache to the specified size. Make sure this code * is agnostic to what underlying SSL technology we use. */ CURLcode Curl_ssl_initsessions(struct SessionHandle *data, size_t amount) { struct curl_ssl_session *session; if(data->state.session) /* this is just a precaution to prevent multiple inits */ return CURLE_OK; session = calloc(amount, sizeof(struct curl_ssl_session)); if(!session) return CURLE_OUT_OF_MEMORY; /* store the info in the SSL section */ data->set.ssl.max_ssl_sessions = amount; data->state.session = session; data->state.sessionage = 1; /* this is brand new */ return CURLE_OK; } size_t Curl_ssl_version(char *buffer, size_t size) { return curlssl_version(buffer, size); } /* * This function tries to determine connection status. * * Return codes: * 1 means the connection is still in place * 0 means the connection has been closed * -1 means the connection status is unknown */ int Curl_ssl_check_cxn(struct connectdata *conn) { return curlssl_check_cxn(conn); } bool Curl_ssl_data_pending(const struct connectdata *conn, int connindex) { return curlssl_data_pending(conn, connindex); } void Curl_ssl_free_certinfo(struct SessionHandle *data) { int i; struct curl_certinfo *ci = &data->info.certs; if(ci->num_of_certs) { /* free all individual lists used */ for(i=0; inum_of_certs; i++) { curl_slist_free_all(ci->certinfo[i]); ci->certinfo[i] = NULL; } free(ci->certinfo); /* free the actual array too */ ci->certinfo = NULL; ci->num_of_certs = 0; } } CURLcode Curl_ssl_init_certinfo(struct SessionHandle *data, int num) { struct curl_certinfo *ci = &data->info.certs; struct curl_slist **table; /* Free any previous certificate information structures */ Curl_ssl_free_certinfo(data); /* Allocate the required certificate information structures */ table = calloc((size_t) num, sizeof(struct curl_slist *)); if(!table) return CURLE_OUT_OF_MEMORY; ci->num_of_certs = num; ci->certinfo = table; return CURLE_OK; } /* * 'value' is NOT a zero terminated string */ CURLcode Curl_ssl_push_certinfo_len(struct SessionHandle *data, int certnum, const char *label, const char *value, size_t valuelen) { struct curl_certinfo * ci = &data->info.certs; char * output; struct curl_slist * nl; CURLcode result = CURLE_OK; size_t labellen = strlen(label); size_t outlen = labellen + 1 + valuelen + 1; /* label:value\0 */ output = malloc(outlen); if(!output) return CURLE_OUT_OF_MEMORY; /* sprintf the label and colon */ snprintf(output, outlen, "%s:", label); /* memcpy the value (it might not be zero terminated) */ memcpy(&output[labellen+1], value, valuelen); /* zero terminate the output */ output[labellen + 1 + valuelen] = 0; nl = Curl_slist_append_nodup(ci->certinfo[certnum], output); if(!nl) { free(output); curl_slist_free_all(ci->certinfo[certnum]); result = CURLE_OUT_OF_MEMORY; } ci->certinfo[certnum] = nl; return result; } /* * This is a convenience function for push_certinfo_len that takes a zero * terminated value. */ CURLcode Curl_ssl_push_certinfo(struct SessionHandle *data, int certnum, const char *label, const char *value) { size_t valuelen = strlen(value); return Curl_ssl_push_certinfo_len(data, certnum, label, value, valuelen); } int Curl_ssl_random(struct SessionHandle *data, unsigned char *entropy, size_t length) { return curlssl_random(data, entropy, length); } /* * Public key pem to der conversion */ static CURLcode pubkey_pem_to_der(const char *pem, unsigned char **der, size_t *der_len) { char *stripped_pem, *begin_pos, *end_pos; size_t pem_count, stripped_pem_count = 0, pem_len; CURLcode result; /* if no pem, exit. */ if(!pem) return CURLE_BAD_CONTENT_ENCODING; begin_pos = strstr(pem, "-----BEGIN PUBLIC KEY-----"); if(!begin_pos) return CURLE_BAD_CONTENT_ENCODING; pem_count = begin_pos - pem; /* Invalid if not at beginning AND not directly following \n */ if(0 != pem_count && '\n' != pem[pem_count - 1]) return CURLE_BAD_CONTENT_ENCODING; /* 26 is length of "-----BEGIN PUBLIC KEY-----" */ pem_count += 26; /* Invalid if not directly following \n */ end_pos = strstr(pem + pem_count, "\n-----END PUBLIC KEY-----"); if(!end_pos) return CURLE_BAD_CONTENT_ENCODING; pem_len = end_pos - pem; stripped_pem = malloc(pem_len - pem_count + 1); if(!stripped_pem) return CURLE_OUT_OF_MEMORY; /* * Here we loop through the pem array one character at a time between the * correct indices, and place each character that is not '\n' or '\r' * into the stripped_pem array, which should represent the raw base64 string */ while(pem_count < pem_len) { if('\n' != pem[pem_count] && '\r' != pem[pem_count]) stripped_pem[stripped_pem_count++] = pem[pem_count]; ++pem_count; } /* Place the null terminator in the correct place */ stripped_pem[stripped_pem_count] = '\0'; result = Curl_base64_decode(stripped_pem, der, der_len); Curl_safefree(stripped_pem); return result; } /* * Generic pinned public key check. */ CURLcode Curl_pin_peer_pubkey(struct SessionHandle *data, const char *pinnedpubkey, const unsigned char *pubkey, size_t pubkeylen) { FILE *fp; unsigned char *buf = NULL, *pem_ptr = NULL; long filesize; size_t size, pem_len; CURLcode pem_read; CURLcode result = CURLE_SSL_PINNEDPUBKEYNOTMATCH; #ifdef curlssl_sha256sum CURLcode encode; size_t encodedlen, pinkeylen; char *encoded, *pinkeycopy, *begin_pos, *end_pos; unsigned char *sha256sumdigest = NULL; #endif /* if a path wasn't specified, don't pin */ if(!pinnedpubkey) return CURLE_OK; if(!pubkey || !pubkeylen) return result; #ifdef curlssl_sha256sum /* only do this if pinnedpubkey starts with "sha256//", length 8 */ if(strncmp(pinnedpubkey, "sha256//", 8) == 0) { /* compute sha256sum of public key */ sha256sumdigest = malloc(SHA256_DIGEST_LENGTH); if(!sha256sumdigest) return CURLE_OUT_OF_MEMORY; curlssl_sha256sum(pubkey, pubkeylen, sha256sumdigest, SHA256_DIGEST_LENGTH); encode = Curl_base64_encode(data, (char *)sha256sumdigest, SHA256_DIGEST_LENGTH, &encoded, &encodedlen); Curl_safefree(sha256sumdigest); if(encode) return encode; infof(data, "\t public key hash: sha256//%s\n", encoded); /* it starts with sha256//, copy so we can modify it */ pinkeylen = strlen(pinnedpubkey) + 1; pinkeycopy = malloc(pinkeylen); if(!pinkeycopy) { Curl_safefree(encoded); return CURLE_OUT_OF_MEMORY; } memcpy(pinkeycopy, pinnedpubkey, pinkeylen); /* point begin_pos to the copy, and start extracting keys */ begin_pos = pinkeycopy; do { end_pos = strstr(begin_pos, ";sha256//"); /* * if there is an end_pos, null terminate, * otherwise it'll go to the end of the original string */ if(end_pos) end_pos[0] = '\0'; /* compare base64 sha256 digests, 8 is the length of "sha256//" */ if(encodedlen == strlen(begin_pos + 8) && !memcmp(encoded, begin_pos + 8, encodedlen)) { result = CURLE_OK; break; } /* * change back the null-terminator we changed earlier, * and look for next begin */ if(end_pos) { end_pos[0] = ';'; begin_pos = strstr(end_pos, "sha256//"); } } while(end_pos && begin_pos); Curl_safefree(encoded); Curl_safefree(pinkeycopy); return result; } #else (void)data; #endif fp = fopen(pinnedpubkey, "rb"); if(!fp) return result; do { /* Determine the file's size */ if(fseek(fp, 0, SEEK_END)) break; filesize = ftell(fp); if(fseek(fp, 0, SEEK_SET)) break; if(filesize < 0 || filesize > MAX_PINNED_PUBKEY_SIZE) break; /* * if the size of our certificate is bigger than the file * size then it can't match */ size = curlx_sotouz((curl_off_t) filesize); if(pubkeylen > size) break; /* * Allocate buffer for the pinned key * With 1 additional byte for null terminator in case of PEM key */ buf = malloc(size + 1); if(!buf) break; /* Returns number of elements read, which should be 1 */ if((int) fread(buf, size, 1, fp) != 1) break; /* If the sizes are the same, it can't be base64 encoded, must be der */ if(pubkeylen == size) { if(!memcmp(pubkey, buf, pubkeylen)) result = CURLE_OK; break; } /* * Otherwise we will assume it's PEM and try to decode it * after placing null terminator */ buf[size] = '\0'; pem_read = pubkey_pem_to_der((const char *)buf, &pem_ptr, &pem_len); /* if it wasn't read successfully, exit */ if(pem_read) break; /* * if the size of our certificate doesn't match the size of * the decoded file, they can't be the same, otherwise compare */ if(pubkeylen == pem_len && !memcmp(pubkey, pem_ptr, pubkeylen)) result = CURLE_OK; } while(0); Curl_safefree(buf); Curl_safefree(pem_ptr); fclose(fp); return result; } #ifndef CURL_DISABLE_CRYPTO_AUTH CURLcode Curl_ssl_md5sum(unsigned char *tmp, /* input */ size_t tmplen, unsigned char *md5sum, /* output */ size_t md5len) { #ifdef curlssl_md5sum curlssl_md5sum(tmp, tmplen, md5sum, md5len); #else MD5_context *MD5pw; (void) md5len; MD5pw = Curl_MD5_init(Curl_DIGEST_MD5); if(!MD5pw) return CURLE_OUT_OF_MEMORY; Curl_MD5_update(MD5pw, tmp, curlx_uztoui(tmplen)); Curl_MD5_final(MD5pw, md5sum); #endif return CURLE_OK; } #endif /* * Check whether the SSL backend supports the status_request extension. */ bool Curl_ssl_cert_status_request(void) { #ifdef curlssl_cert_status_request return curlssl_cert_status_request(); #else return FALSE; #endif } /* * Check whether the SSL backend supports false start. */ bool Curl_ssl_false_start(void) { #ifdef curlssl_false_start return curlssl_false_start(); #else return FALSE; #endif } #endif /* USE_SSL */