--- /dev/null
+/*
+ * IRC - Internet Relay Chat, ircd/m_burst.c
+ * Copyright (C) 1990 Jarkko Oikarinen and
+ * University of Oulu, Computing Center
+ *
+ * See file AUTHORS in IRC package for additional names of
+ * the programmers.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 1, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * $Id$
+ */
+
+/*
+ * m_functions execute protocol messages on this server:
+ *
+ * cptr is always NON-NULL, pointing to a *LOCAL* client
+ * structure (with an open socket connected!). This
+ * identifies the physical socket where the message
+ * originated (or which caused the m_function to be
+ * executed--some m_functions may call others...).
+ *
+ * sptr is the source of the message, defined by the
+ * prefix part of the message if present. If not
+ * or prefix not found, then sptr==cptr.
+ *
+ * (!IsServer(cptr)) => (cptr == sptr), because
+ * prefixes are taken *only* from servers...
+ *
+ * (IsServer(cptr))
+ * (sptr == cptr) => the message didn't
+ * have the prefix.
+ *
+ * (sptr != cptr && IsServer(sptr) means
+ * the prefix specified servername. (?)
+ *
+ * (sptr != cptr && !IsServer(sptr) means
+ * that message originated from a remote
+ * user (not local).
+ *
+ * combining
+ *
+ * (!IsServer(sptr)) means that, sptr can safely
+ * taken as defining the target structure of the
+ * message in this server.
+ *
+ * *Always* true (if 'parse' and others are working correct):
+ *
+ * 1) sptr->from == cptr (note: cptr->from == cptr)
+ *
+ * 2) MyConnect(sptr) <=> sptr == cptr (e.g. sptr
+ * *cannot* be a local connection, unless it's
+ * actually cptr!). [MyConnect(x) should probably
+ * be defined as (x == x->from) --msa ]
+ *
+ * parc number of variable parameter strings (if zero,
+ * parv is allowed to be NULL)
+ *
+ * parv a NULL terminated list of parameter pointers,
+ *
+ * parv[0], sender (prefix string), if not present
+ * this points to an empty string.
+ * parv[1]...parv[parc-1]
+ * pointers to additional parameters
+ * parv[parc] == NULL, *always*
+ *
+ * note: it is guaranteed that parv[0]..parv[parc-1] are all
+ * non-NULL pointers.
+ */
+#include "config.h"
+
+#include "channel.h"
+#include "client.h"
+#include "hash.h"
+#include "ircd.h"
+#include "ircd_alloc.h"
+#include "ircd_features.h"
+#include "ircd_log.h"
+#include "ircd_reply.h"
+#include "ircd_string.h"
+#include "list.h"
+#include "match.h"
+#include "msg.h"
+#include "numeric.h"
+#include "numnicks.h"
+#include "s_conf.h"
+#include "s_misc.h"
+#include "send.h"
+#include "struct.h"
+#include "ircd_snprintf.h"
+
+/* #include <assert.h> -- Now using assert in ircd_log.h */
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+
+static int
+netride_modes(int parc, char **parv, const char *curr_key)
+{
+ char *modes = parv[0];
+ int result = 0;
+
+ assert(modes && modes[0] == '+');
+ while (*modes) {
+ switch (*modes++) {
+ case '-':
+ return -1;
+ case 'i':
+ result |= MODE_INVITEONLY;
+ break;
+ case 'k':
+ if (strcmp(curr_key, *++parv))
+ result |= MODE_KEY;
+ break;
+ case 'l':
+ ++parv;
+ break;
+ case 'r':
+ result |= MODE_REGONLY;
+ break;
+ }
+ }
+ return result;
+}
+
+/*
+ * ms_burst - server message handler
+ *
+ * -- by Run carlo@runaway.xs4all.nl december 1995 till march 1997
+ *
+ * parv[0] = sender prefix
+ * parv[1] = channel name
+ * parv[2] = channel timestamp
+ * The meaning of the following parv[]'s depend on their first character:
+ * If parv[n] starts with a '+':
+ * Net burst, additive modes
+ * parv[n] = <mode>
+ * parv[n+1] = <param> (optional)
+ * parv[n+2] = <param> (optional)
+ * If parv[n] starts with a '%', then n will be parc-1:
+ * parv[n] = %<ban> <ban> <ban> ...
+ * If parv[n] starts with another character:
+ * parv[n] = <nick>[:<mode>],<nick>[:<mode>],...
+ * where <mode> defines the mode and op-level
+ * for nick and all following nicks until the
+ * next <mode> field.
+ * Digits in the <mode> field have of two meanings:
+ * 1) if it is the first field in this BURST message
+ * that contains digits, and/or when a 'v' is
+ * present in the <mode>:
+ * The absolute value of the op-level.
+ * 2) if there are only digits in this field and
+ * it is not the first field with digits:
+ * An op-level increment relative to the previous
+ * op-level.
+ * First all modeless nicks must be emmitted,
+ * then all combinations of modes without ops
+ * (currently that is only 'v') followed by the same
+ * series but then with ops (currently 'o','ov').
+ *
+ * Example:
+ * "A8 B #test 87654321 +ntkAl key secret 123 A8AAG,A8AAC:v,A8AAA:0,A8AAF:2,A8AAD,A8AAB:v1,A8AAE:1 :%ban1 ban2"
+ *
+ * <mode> list example:
+ *
+ * "xxx,sss:v,ttt,aaa:123,bbb,ccc:2,ddd,kkk:v2,lll:2,mmm"
+ *
+ * means
+ *
+ * xxx // first modeless nicks
+ * sss +v // then opless nicks
+ * ttt +v // no ":<mode>": everything stays the same
+ * aaa -123 // first field with digit: absolute value
+ * bbb -123
+ * ccc -125 // only digits, not first field: increment
+ * ddd -125
+ * kkk -2 +v // field with a 'v': absolute value
+ * lll -4 +v // only digits: increment
+ * mmm -4 +v
+ *
+ * Anti net.ride code.
+ *
+ * When the channel already exist, and its TS is larger than
+ * the TS in the BURST message, then we cancel all existing modes.
+ * If its is smaller then the received BURST message is ignored.
+ * If it's equal, then the received modes are just added.
+ *
+ * BURST is also accepted outside a netburst now because it
+ * is sent upstream as reaction to a DESTRUCT message. For
+ * these BURST messages it is possible that the listed channel
+ * members are already joined.
+ */
+int ms_burst(struct Client *cptr, struct Client *sptr, int parc, char *parv[])
+{
+ struct ModeBuf modebuf, *mbuf = 0;
+ struct Channel *chptr;
+ time_t timestamp;
+ struct Membership *member, *nmember;
+ struct Ban *lp, **lp_p;
+ unsigned int parse_flags = (MODE_PARSE_FORCE | MODE_PARSE_BURST);
+ int param, nickpos = 0, banpos = 0;
+ char modestr[BUFSIZE], nickstr[BUFSIZE], banstr[BUFSIZE];
+
+ if (parc < 3)
+ return protocol_violation(sptr,"Too few parameters for BURST");
+
+ if (!(chptr = get_channel(sptr, parv[1], CGT_CREATE)))
+ return 0; /* can't create the channel? */
+
+ timestamp = atoi(parv[2]);
+
+ if (chptr->creationtime) /* 0 for new (empty) channels,
+ i.e. when this server just restarted. */
+ {
+ if (parc == 3) /* Zannel BURST? */
+ {
+ /* An empty channel without +A set, will cause a BURST message
+ with exactly 3 parameters (because all modes have been reset).
+ If the timestamp on such channels is only a few seconds older
+ from our own, then we ignore this burst: we do not deop our
+ own side.
+ Likewise, we expect the other (empty) side to copy our timestamp
+ from our own BURST message, even though it is slightly larger.
+
+ The reason for this is to allow people to join an empty
+ non-A channel (a zannel) during a net.split, and not be
+ deopped when the net reconnects (with another zannel). When
+ someone joins a split zannel, their side increments the TS by one.
+ If they cycle a few times then we still don't have a reason to
+ deop them. Theoretically I see no reason not to accept ANY timestamp,
+ but to be sure, we only accept timestamps that are just a few
+ seconds off (one second for each time they cycled the channel). */
+
+ /* Don't even deop users who cycled four times during the net.break. */
+ if (timestamp < chptr->creationtime &&
+ chptr->creationtime <= timestamp + 4 &&
+ chptr->users != 0) /* Only do this when WE have users, so that
+ if we do this the BURST that we sent has
+ parc > 3 and the other side will use the
+ test below: */
+ timestamp = chptr->creationtime; /* Do not deop our side. */
+ }
+ else if (chptr->creationtime < timestamp &&
+ timestamp <= chptr->creationtime + 4 &&
+ chptr->users == 0)
+ {
+ /* If one side of the net.junction does the above
+ timestamp = chptr->creationtime, then the other
+ side must do this: */
+ chptr->creationtime = timestamp; /* Use the same TS on both sides. */
+ }
+ /* In more complex cases, we might still end up with a
+ creationtime desync of a few seconds, but that should
+ be synced automatically rather quickly (every JOIN
+ caries a timestamp and will sync it; modes by users do
+ not carry timestamps and are accepted regardless).
+ Only when nobody joins the channel on the side with
+ the oldest timestamp before a new net.break occurs
+ precisely inbetween the desync, an unexpected bounce
+ might happen on reconnect. */
+ }
+
+ if (!chptr->creationtime || chptr->creationtime > timestamp) {
+ /*
+ * Kick local members if channel is +i or +k and our TS was larger
+ * than the burst TS (anti net.ride). The modes hack is here because
+ * we have to do this before mode_parse, as chptr may go away.
+ */
+ for (param = 3; param < parc; param++)
+ {
+ int check_modes;
+ if (parv[param][0] != '+')
+ continue;
+ check_modes = netride_modes(parc - param, parv + param, chptr->mode.key);
+ if (check_modes < 0)
+ {
+ if (chptr->users == 0)
+ sub1_from_channel(chptr);
+ return protocol_violation(sptr, "Invalid mode string in BURST");
+ }
+ else if (check_modes)
+ {
+ /* Clear any outstanding rogue invites */
+ mode_invite_clear(chptr);
+ for (member = chptr->members; member; member = nmember)
+ {
+ nmember = member->next_member;
+ if (!MyUser(member->user) || IsZombie(member))
+ continue;
+ /* Kick as netrider if key mismatch *or* remote channel is
+ * +i (unless user is an oper) *or* remote channel is +r
+ * (unless user has an account).
+ */
+ if (!(check_modes & MODE_KEY)
+ && (!(check_modes & MODE_INVITEONLY) || IsAnOper(member->user))
+ && (!(check_modes & MODE_REGONLY) || IsAccount(member->user)))
+ continue;
+ sendcmdto_serv_butone(&me, CMD_KICK, NULL, "%H %C :Net Rider", chptr, member->user);
+ sendcmdto_channel_butserv_butone(&his, CMD_KICK, chptr, NULL, 0, "%H %C :Net Rider", chptr, member->user);
+ make_zombie(member, member->user, &me, &me, chptr);
+ }
+ }
+ break;
+ }
+
+ /* If the channel had only locals, it went away by now. */
+ if (!(chptr = get_channel(sptr, parv[1], CGT_CREATE)))
+ return 0; /* can't create the channel? */
+ }
+
+ /* turn off burst joined flag */
+ for (member = chptr->members; member; member = member->next_member)
+ member->status &= ~(CHFL_BURST_JOINED|CHFL_BURST_ALREADY_OPPED|CHFL_BURST_ALREADY_VOICED);
+
+ if (!chptr->creationtime) /* mark channel as created during BURST */
+ chptr->mode.mode |= MODE_BURSTADDED;
+
+ /* new channel or an older one */
+ if (!chptr->creationtime || chptr->creationtime > timestamp) {
+ chptr->creationtime = timestamp;
+
+ modebuf_init(mbuf = &modebuf, &me, cptr, chptr,
+ MODEBUF_DEST_CHANNEL | MODEBUF_DEST_NOKEY);
+ modebuf_mode(mbuf, MODE_DEL | chptr->mode.mode); /* wipeout modes */
+ chptr->mode.mode &= MODE_BURSTADDED | MODE_WASDELJOINS;
+
+ /* wipeout any limit and keys that are set */
+ parse_flags |= (MODE_PARSE_SET | MODE_PARSE_WIPEOUT);
+
+ /* mark bans for wipeout */
+ for (lp = chptr->banlist; lp; lp = lp->next)
+ lp->flags |= BAN_BURST_WIPEOUT;
+
+ /* clear topic set by netrider (if set) */
+ if (*chptr->topic) {
+ *chptr->topic = '\0';
+ *chptr->topic_nick = '\0';
+ chptr->topic_time = 0;
+ sendcmdto_channel_butserv_butone(&his, CMD_TOPIC, chptr, NULL, 0,
+ "%H :%s", chptr, chptr->topic);
+ }
+ } else if (chptr->creationtime == timestamp) {
+ modebuf_init(mbuf = &modebuf, &me, cptr, chptr,
+ MODEBUF_DEST_CHANNEL | MODEBUF_DEST_NOKEY);
+
+ parse_flags |= MODE_PARSE_SET; /* set new modes */
+ }
+
+ param = 3; /* parse parameters */
+ while (param < parc) {
+ switch (*parv[param]) {
+ case '+': /* parameter introduces a mode string */
+ param += mode_parse(mbuf, cptr, sptr, chptr, parc - param,
+ parv + param, parse_flags, NULL);
+ break;
+
+ case '%': /* parameter contains bans */
+ if (parse_flags & MODE_PARSE_SET) {
+ char *banlist = parv[param] + 1, *p = 0, *ban, *ptr;
+ struct Ban *newban;
+
+ for (ban = ircd_strtok(&p, banlist, " "); ban;
+ ban = ircd_strtok(&p, 0, " ")) {
+ ban = collapse(pretty_mask(ban));
+
+ /*
+ * Yeah, we should probably do this elsewhere, and make it better
+ * and more general; this will hold until we get there, though.
+ * I dislike the current add_banid API... -Kev
+ *
+ * I wish there were a better algo. for this than the n^2 one
+ * shown below *sigh*
+ */
+ for (lp = chptr->banlist; lp; lp = lp->next) {
+ if (!ircd_strcmp(lp->banstr, ban)) {
+ ban = 0; /* don't add ban */
+ lp->flags &= ~BAN_BURST_WIPEOUT; /* not wiping out */
+ break; /* new ban already existed; don't even repropagate */
+ } else if (!(lp->flags & BAN_BURST_WIPEOUT) &&
+ !mmatch(lp->banstr, ban)) {
+ ban = 0; /* don't add ban unless wiping out bans */
+ break; /* new ban is encompassed by an existing one; drop */
+ } else if (!mmatch(ban, lp->banstr))
+ lp->flags |= BAN_OVERLAPPED; /* remove overlapping ban */
+
+ if (!lp->next)
+ break;
+ }
+
+ if (ban) { /* add the new ban to the end of the list */
+ /* Build ban buffer */
+ if (!banpos) {
+ banstr[banpos++] = ' ';
+ banstr[banpos++] = ':';
+ banstr[banpos++] = '%';
+ } else
+ banstr[banpos++] = ' ';
+ for (ptr = ban; *ptr; ptr++) /* add ban to buffer */
+ banstr[banpos++] = *ptr;
+
+ newban = make_ban(ban); /* create new ban */
+ strcpy(newban->who, "*");
+ newban->when = TStime();
+ newban->flags |= BAN_BURSTED;
+ newban->next = 0;
+ if (lp)
+ lp->next = newban; /* link it in */
+ else
+ chptr->banlist = newban;
+ }
+ }
+ }
+ param++; /* look at next param */
+ break;
+
+ default: /* parameter contains clients */
+ {
+ struct Client *acptr;
+ char *nicklist = parv[param], *p = 0, *nick, *ptr;
+ int current_mode, last_mode, base_mode;
+ int oplevel = -1; /* Mark first field with digits: means the same as 'o' (but with level). */
+ int last_oplevel = 0;
+ struct Membership* member;
+
+ base_mode = CHFL_DEOPPED | CHFL_BURST_JOINED;
+ if (chptr->mode.mode & MODE_DELJOINS)
+ base_mode |= CHFL_DELAYED;
+ current_mode = last_mode = base_mode;
+
+ for (nick = ircd_strtok(&p, nicklist, ","); nick;
+ nick = ircd_strtok(&p, 0, ",")) {
+
+ if ((ptr = strchr(nick, ':'))) { /* new flags; deal */
+ *ptr++ = '\0';
+
+ if (parse_flags & MODE_PARSE_SET) {
+ int current_mode_needs_reset;
+ for (current_mode_needs_reset = 1; *ptr; ptr++) {
+ if (*ptr == 'o') { /* has oper status */
+ /*
+ * An 'o' is pre-oplevel protocol, so this is only for
+ * backwards compatibility. Give them an op-level of
+ * MAXOPLEVEL so everyone can deop them.
+ */
+ oplevel = MAXOPLEVEL;
+ if (current_mode_needs_reset) {
+ current_mode = base_mode;
+ current_mode_needs_reset = 0;
+ }
+ current_mode = (current_mode & ~(CHFL_DEOPPED | CHFL_DELAYED)) | CHFL_CHANOP;
+ /*
+ * Older servers may send XXYYY:ov, in which case we
+ * do not want to use the code for 'v' below.
+ */
+ if (ptr[1] == 'v') {
+ current_mode |= CHFL_VOICE;
+ ptr++;
+ }
+ }
+ else if (*ptr == 'v') { /* has voice status */
+ if (current_mode_needs_reset) {
+ current_mode = base_mode;
+ current_mode_needs_reset = 0;
+ }
+ current_mode = (current_mode & ~CHFL_DELAYED) | CHFL_VOICE;
+ oplevel = -1; /* subsequent digits are an absolute op-level value. */
+ }
+ else if (IsDigit(*ptr)) {
+ int level_increment = 0;
+ if (oplevel == -1) { /* op-level is absolute value? */
+ if (current_mode_needs_reset) {
+ current_mode = base_mode;
+ current_mode_needs_reset = 0;
+ }
+ oplevel = 0;
+ }
+ current_mode = (current_mode & ~(CHFL_DEOPPED | CHFL_DELAYED)) | CHFL_CHANOP;
+ do {
+ level_increment = 10 * level_increment + *ptr++ - '0';
+ } while (IsDigit(*ptr));
+ --ptr;
+ oplevel += level_increment;
+ if (oplevel > MAXOPLEVEL) {
+ protocol_violation(sptr, "Invalid cumulative oplevel %u during burst", oplevel);
+ oplevel = MAXOPLEVEL;
+ break;
+ }
+ }
+ else { /* I don't recognize that flag */
+ protocol_violation(sptr, "Invalid flag '%c' in nick part of burst", *ptr);
+ break; /* so stop processing */
+ }
+ }
+ }
+ }
+
+ if (!(acptr = findNUser(nick)) || cli_from(acptr) != cptr)
+ continue; /* ignore this client */
+
+ /* Build nick buffer */
+ nickstr[nickpos] = nickpos ? ',' : ' '; /* first char */
+ nickpos++;
+
+ for (ptr = nick; *ptr; ptr++) /* store nick */
+ nickstr[nickpos++] = *ptr;
+
+ if (current_mode != last_mode) { /* if mode changed... */
+ last_mode = current_mode;
+ last_oplevel = oplevel;
+
+ nickstr[nickpos++] = ':'; /* add a specifier */
+ if (current_mode & CHFL_VOICE)
+ nickstr[nickpos++] = 'v';
+ if (current_mode & CHFL_CHANOP)
+ {
+ if (oplevel != MAXOPLEVEL)
+ nickpos += ircd_snprintf(0, nickstr + nickpos, sizeof(nickstr) - nickpos, "%u", oplevel);
+ else
+ nickstr[nickpos++] = 'o';
+ }
+ } else if (current_mode & CHFL_CHANOP && oplevel != last_oplevel) { /* if just op level changed... */
+ nickstr[nickpos++] = ':'; /* add a specifier */
+ nickpos += ircd_snprintf(0, nickstr + nickpos, sizeof(nickstr) - nickpos, "%u", oplevel - last_oplevel);
+ last_oplevel = oplevel;
+ }
+
+ if (!(member = find_member_link(chptr, acptr)))
+ {
+ add_user_to_channel(chptr, acptr, current_mode, oplevel);
+ if (!(current_mode & CHFL_DELAYED))
+ sendcmdto_channel_butserv_butone(acptr, CMD_JOIN, chptr, NULL, 0, "%H", chptr);
+ }
+ else
+ {
+ /* The member was already joined (either by CREATE or JOIN).
+ Remember the current mode. */
+ if (member->status & CHFL_CHANOP)
+ member->status |= CHFL_BURST_ALREADY_OPPED;
+ if (member->status & CHFL_VOICE)
+ member->status |= CHFL_BURST_ALREADY_VOICED;
+ /* Synchronize with the burst. */
+ member->status |= CHFL_BURST_JOINED | (current_mode & (CHFL_CHANOP|CHFL_VOICE));
+ SetOpLevel(member, oplevel);
+ }
+ }
+ }
+ param++;
+ break;
+ } /* switch (*parv[param]) */
+ } /* while (param < parc) */
+
+ nickstr[nickpos] = '\0';
+ banstr[banpos] = '\0';
+
+ if (parse_flags & MODE_PARSE_SET) {
+ modebuf_extract(mbuf, modestr + 1); /* for sending BURST onward */
+ modestr[0] = modestr[1] ? ' ' : '\0';
+ } else
+ modestr[0] = '\0';
+
+ sendcmdto_serv_butone(sptr, CMD_BURST, cptr, "%H %Tu%s%s%s", chptr,
+ chptr->creationtime, modestr, nickstr, banstr);
+
+ if (parse_flags & MODE_PARSE_WIPEOUT || banpos)
+ mode_ban_invalidate(chptr);
+
+ if (parse_flags & MODE_PARSE_SET) { /* any modes changed? */
+ /* first deal with channel members */
+ for (member = chptr->members; member; member = member->next_member) {
+ if (member->status & CHFL_BURST_JOINED) { /* joined during burst */
+ if ((member->status & CHFL_CHANOP) && !(member->status & CHFL_BURST_ALREADY_OPPED))
+ modebuf_mode_client(mbuf, MODE_ADD | CHFL_CHANOP, member->user, OpLevel(member));
+ if ((member->status & CHFL_VOICE) && !(member->status & CHFL_BURST_ALREADY_VOICED))
+ modebuf_mode_client(mbuf, MODE_ADD | CHFL_VOICE, member->user, OpLevel(member));
+ } else if (parse_flags & MODE_PARSE_WIPEOUT) { /* wipeout old ops */
+ if (member->status & CHFL_CHANOP)
+ modebuf_mode_client(mbuf, MODE_DEL | CHFL_CHANOP, member->user, OpLevel(member));
+ if (member->status & CHFL_VOICE)
+ modebuf_mode_client(mbuf, MODE_DEL | CHFL_VOICE, member->user, OpLevel(member));
+ member->status = (member->status
+ & ~(CHFL_CHANNEL_MANAGER | CHFL_CHANOP | CHFL_VOICE))
+ | CHFL_DEOPPED;
+ }
+ }
+
+ /* Now deal with channel bans */
+ lp_p = &chptr->banlist;
+ while (*lp_p) {
+ lp = *lp_p;
+
+ /* remove ban from channel */
+ if (lp->flags & (BAN_OVERLAPPED | BAN_BURST_WIPEOUT)) {
+ char *bandup;
+ DupString(bandup, lp->banstr);
+ modebuf_mode_string(mbuf, MODE_DEL | MODE_BAN,
+ bandup, 1);
+ *lp_p = lp->next; /* clip out of list */
+ free_ban(lp);
+ continue;
+ } else if (lp->flags & BAN_BURSTED) /* add ban to channel */
+ modebuf_mode_string(mbuf, MODE_ADD | MODE_BAN,
+ lp->banstr, 0); /* don't free banstr */
+
+ lp->flags &= BAN_IPMASK; /* reset the flag */
+ lp_p = &(*lp_p)->next;
+ }
+ }
+
+ return mbuf ? modebuf_flush(mbuf) : 0;
+}
projects / ircu2.10.12-pk.git / blobdiff