X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fmeta.c;h=ccc3b2e670d5ae9a0210929d804703323f97983f;hp=0b8a379b2b70bc87c8e527aa8d249dbfe8005dfe;hb=5c5ae8c48e0414cb4831ccfd2b147ab65bb5fd5c;hpb=a0c544df5d882bea812fb0ef648cdee98939e89c diff --git a/src/meta.c b/src/meta.c index 0b8a379b..ccc3b2e6 100644 --- a/src/meta.c +++ b/src/meta.c @@ -1,6 +1,6 @@ /* meta.c -- handle the meta communication - Copyright (C) 2000-2013 Guus Sliepen , + Copyright (C) 2000-2017 Guus Sliepen , 2000-2005 Ivo Timmermans 2006 Scott Lamb @@ -30,6 +30,7 @@ #include "meta.h" #include "net.h" #include "protocol.h" +#include "proxy.h" #include "utils.h" #include "xalloc.h" @@ -61,6 +62,14 @@ bool send_meta(connection_t *c, const char *buffer, int length) { /* Add our data to buffer */ if(c->status.encryptout) { + /* Check encryption limits */ + if(length > c->outbudget) { + ifdebug(META) logger(LOG_ERR, "Byte limit exceeded for encryption to %s (%s)", c->name, c->hostname); + return false; + } else { + c->outbudget -= length; + } + result = EVP_EncryptUpdate(c->outctx, (unsigned char *)c->outbuf + c->outbufstart + c->outbuflen, &outlen, (unsigned char *)buffer, length); if(!result || outlen < length) { @@ -95,7 +104,7 @@ bool flush_meta(connection_t *c) { } else if(errno == EINTR) { continue; } else if(sockwouldblock(sockerrno)) { - ifdebug(CONNECTIONS) logger(LOG_DEBUG, "Flushing %d bytes to %s (%s) would block", + ifdebug(META) logger(LOG_DEBUG, "Flushing %d bytes to %s (%s) would block", c->outbuflen, c->name, c->hostname); return true; } else { @@ -160,9 +169,28 @@ bool receive_meta(connection_t *c) { c->buflen += lenin; while(lenin > 0) { + reqlen = 0; + + /* Is it proxy metadata? */ + + if(c->allow_request == PROXY) { + reqlen = receive_proxy_meta(c, oldlen, lenin); + if(reqlen < 0) + return false; + goto consume; + } + /* Decrypt */ if(c->status.decryptin && !decrypted) { + /* Check decryption limits */ + if(lenin > c->inbudget) { + ifdebug(META) logger(LOG_ERR, "Byte limit exceeded for decryption from %s (%s)", c->name, c->hostname); + return false; + } else { + c->inbudget -= lenin; + } + result = EVP_DecryptUpdate(c->inctx, (unsigned char *)inbuf, &lenout, (unsigned char *)c->buffer + oldlen, lenin); if(!result || lenout != lenin) { logger(LOG_ERR, "Error while decrypting metadata from %s (%s): %s", @@ -177,74 +205,32 @@ bool receive_meta(connection_t *c) { if(c->tcplen) { if(c->tcplen <= c->buflen) { - if(!c->node) { - if(c->outgoing && proxytype == PROXY_SOCKS4 && c->allow_request == ID) { - if(c->buffer[0] == 0 && c->buffer[1] == 0x5a) { - ifdebug(CONNECTIONS) logger(LOG_DEBUG, "Proxy request granted"); - } else { - logger(LOG_ERR, "Proxy request rejected"); - return false; - } - } else if(c->outgoing && proxytype == PROXY_SOCKS5 && c->allow_request == ID) { - if(c->buffer[0] != 5) { - logger(LOG_ERR, "Invalid response from proxy server"); - return false; - } - if(c->buffer[1] == (char)0xff) { - logger(LOG_ERR, "Proxy request rejected: unsuitable authentication method"); - return false; - } - if(c->buffer[2] != 5) { - logger(LOG_ERR, "Invalid response from proxy server"); - return false; - } - if(c->buffer[3] == 0) { - ifdebug(CONNECTIONS) logger(LOG_DEBUG, "Proxy request granted"); - } else { - logger(LOG_ERR, "Proxy request rejected"); - return false; - } - } else { - logger(LOG_ERR, "c->tcplen set but c->node is NULL!"); - abort(); - } - } else { - if(c->allow_request == ALL) { - receive_tcppacket(c, c->buffer, c->tcplen); - } else { - logger(LOG_ERR, "Got unauthorized TCP packet from %s (%s)", c->name, c->hostname); - return false; - } + if(c->allow_request != ALL) { + logger(LOG_ERR, "Got unauthorized TCP packet from %s (%s)", c->name, c->hostname); + return false; } - c->buflen -= c->tcplen; - lenin -= c->tcplen - oldlen; - memmove(c->buffer, c->buffer + c->tcplen, c->buflen); - oldlen = 0; + receive_tcppacket(c, c->buffer, c->tcplen); + reqlen = c->tcplen; c->tcplen = 0; - continue; - } else { - break; } - } - - /* Otherwise we are waiting for a request */ - - reqlen = 0; + } else { + /* Otherwise we are waiting for a request */ - for(i = oldlen; i < c->buflen; i++) { - if(c->buffer[i] == '\n') { - c->buffer[i] = '\0'; /* replace end-of-line by end-of-string so we can use sscanf */ - reqlen = i + 1; - break; + for(i = oldlen; i < c->buflen; i++) { + if(c->buffer[i] == '\n') { + c->buffer[i] = '\0'; /* replace end-of-line by end-of-string so we can use sscanf */ + c->reqlen = reqlen = i + 1; + break; + } } - } - if(reqlen) { - c->reqlen = reqlen; - if(!receive_request(c)) + if(reqlen && !receive_request(c)) return false; + } +consume: + if(reqlen) { c->buflen -= reqlen; lenin -= reqlen - oldlen; memmove(c->buffer, c->buffer + reqlen, c->buflen);