X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fmeta.c;h=ee55ecd78b18050b75bed958cb5cce6b71f7d22a;hp=4c52464c33d2a62f663f54c2b920832b8a20e910;hb=2116c6eb7d328c7aa3ce3da54f95367e5199d373;hpb=e00b44cb98e4d50a0d426048ba01dbd80bcb5941 diff --git a/src/meta.c b/src/meta.c index 4c52464c..ee55ecd7 100644 --- a/src/meta.c +++ b/src/meta.c @@ -1,6 +1,6 @@ /* meta.c -- handle the meta communication - Copyright (C) 2000-2009 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" @@ -37,16 +38,12 @@ bool send_meta(connection_t *c, const char *buffer, int length) { int outlen; int result; - if(!c) { - logger(LOG_ERR, "send_meta() called with NULL pointer!"); - abort(); - } - ifdebug(META) logger(LOG_DEBUG, "Sending %d bytes of metadata to %s (%s)", length, - c->name, c->hostname); + c->name, c->hostname); - if(!c->outbuflen) + if(!c->outbuflen) { c->last_flushed_time = now; + } /* Find room in connection's buffer */ if(length + c->outbuflen > c->outbufsize) { @@ -61,16 +58,26 @@ bool send_meta(connection_t *c, const char *buffer, int length) { /* Add our data to buffer */ if(c->status.encryptout) { + /* Check encryption limits */ + if((uint64_t)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); + &outlen, (unsigned char *)buffer, length); + if(!result || outlen < length) { logger(LOG_ERR, "Error while encrypting metadata to %s (%s): %s", - c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL)); + c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL)); return false; } else if(outlen > length) { logger(LOG_EMERG, "Encrypted data too long! Heap corrupted!"); abort(); } + c->outbuflen += outlen; } else { memcpy(c->outbuf + c->outbufstart + c->outbuflen, buffer, length); @@ -82,25 +89,26 @@ bool send_meta(connection_t *c, const char *buffer, int length) { bool flush_meta(connection_t *c) { int result; - + ifdebug(META) logger(LOG_DEBUG, "Flushing %d bytes to %s (%s)", - c->outbuflen, c->name, c->hostname); + c->outbuflen, c->name, c->hostname); while(c->outbuflen) { result = send(c->socket, c->outbuf + c->outbufstart, c->outbuflen, 0); + if(result <= 0) { if(!errno || errno == EPIPE) { ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Connection closed by %s (%s)", - c->name, c->hostname); + c->name, c->hostname); } else if(errno == EINTR) { continue; } else if(sockwouldblock(sockerrno)) { - ifdebug(CONNECTIONS) logger(LOG_DEBUG, "Flushing %d bytes to %s (%s) would block", - c->outbuflen, c->name, c->hostname); + ifdebug(META) logger(LOG_DEBUG, "Flushing %d bytes to %s (%s) would block", + c->outbuflen, c->name, c->hostname); return true; } else { logger(LOG_ERR, "Flushing meta data to %s (%s) failed: %s", c->name, - c->hostname, sockstrerror(sockerrno)); + c->hostname, sockstrerror(sockerrno)); } return false; @@ -121,8 +129,9 @@ void broadcast_meta(connection_t *from, const char *buffer, int length) { for(node = connection_tree->head; node; node = node->next) { c = node->data; - if(c != from && c->status.active) + if(c != from && c->status.active) { send_meta(c, buffer, length); + } } } @@ -146,12 +155,12 @@ bool receive_meta(connection_t *c) { if(lenin <= 0) { if(!lenin || !errno) { ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Connection closed by %s (%s)", - c->name, c->hostname); - } else if(sockwouldblock(sockerrno)) + c->name, c->hostname); + } else if(sockwouldblock(sockerrno)) { return true; - else + } else logger(LOG_ERR, "Metadata socket read error for %s (%s): %s", - c->name, c->hostname, sockstrerror(sockerrno)); + c->name, c->hostname, sockstrerror(sockerrno)); return false; } @@ -160,15 +169,39 @@ 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); + + if(reqlen < 0) { + return false; + } + + goto consume; + } + /* Decrypt */ if(c->status.decryptin && !decrypted) { + /* Check decryption limits */ + if((uint64_t)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", - c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL)); + c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL)); return false; } + memcpy(c->buffer + oldlen, inbuf, lenin); decrypted = true; } @@ -177,36 +210,34 @@ bool receive_meta(connection_t *c) { if(c->tcplen) { if(c->tcplen <= c->buflen) { - receive_tcppacket(c, c->buffer, c->tcplen); + 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 */ + c->reqlen = 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 */ - reqlen = i + 1; - break; + if(reqlen && !receive_request(c)) { + return false; } } - if(reqlen) { - c->reqlen = reqlen; - if(!receive_request(c)) - return false; +consume: + if(reqlen) { c->buflen -= reqlen; lenin -= reqlen - oldlen; memmove(c->buffer, c->buffer + reqlen, c->buflen); @@ -219,7 +250,7 @@ bool receive_meta(connection_t *c) { if(c->buflen >= MAXBUFSIZE) { logger(LOG_ERR, "Metadata read buffer overflow for %s (%s)", - c->name, c->hostname); + c->name, c->hostname); return false; }