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April 9, 2014 13:35
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This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -0,0 +1,75 @@ int dtls1_process_heartbeat(SSL *s) { unsigned char *p = &s->s3->rrec.data[0], *pl; unsigned short hbtype; unsigned int payload; unsigned int padding = 16; /* Use minimum padding */ /* Read type and payload length first */ hbtype = *p++; //! extracting the length of the payload from the heartbeat request package n2s(p, payload); pl = p; if (s->msg_callback) s->msg_callback(0, s->version, TLS1_RT_HEARTBEAT, &s->s3->rrec.data[0], s->s3->rrec.length, s, s->msg_callback_arg); if (hbtype == TLS1_HB_REQUEST) { unsigned char *buffer, *bp; int r; /* Allocate memory for the response, size is 1 byte * message type, plus 2 bytes payload length, plus * payload, plus padding */ buffer = OPENSSL_malloc(1 + 2 + payload + padding); bp = buffer; /* Enter response type, length and copy payload */ *bp++ = TLS1_HB_RESPONSE; s2n(payload, bp); //! Trying to copy payload from request into response package //! Note that payload might actually specify a length that is greater //! than the length of the request package, therefore memcpy will //! copy the memory behind the package into the response package. //! This will allow the hacker to extract application data //! This error gets repeated several times... memcpy(bp, pl, payload); //! do you want to get hacked? because that is how you get hacked /* Random padding */ RAND_pseudo_bytes(p, padding); r = dtls1_write_bytes(s, TLS1_RT_HEARTBEAT, buffer, 3 + payload + padding); if (r >= 0 && s->msg_callback) s->msg_callback(1, s->version, TLS1_RT_HEARTBEAT, buffer, 3 + payload + padding, s, s->msg_callback_arg); OPENSSL_free(buffer); if (r < 0) return r; } else if (hbtype == TLS1_HB_RESPONSE) { unsigned int seq; /* We only send sequence numbers (2 bytes unsigned int), * and 16 random bytes, so we just try to read the * sequence number */ n2s(pl, seq); if (payload == 18 && seq == s->tlsext_hb_seq) { dtls1_stop_timer(s); s->tlsext_hb_seq++; s->tlsext_hb_pending = 0; } } return 0; }