Mercurial > hg > nginx
view src/http/modules/ngx_http_upstream_ip_hash_module.c @ 7629:f47f7d3d1bfa
Mp4: fixed possible chunk offset overflow.
In "co64" atom chunk start offset is a 64-bit unsigned integer. When trimming
the "mdat" atom, chunk offsets are casted to off_t values which are typically
64-bit signed integers. A specially crafted mp4 file with huge chunk offsets
may lead to off_t overflow and result in negative trim boundaries.
The consequences of the overflow are:
- Incorrect Content-Length header value in the response.
- Negative left boundary of the response file buffer holding the trimmed "mdat".
This leads to pread()/sendfile() errors followed by closing the client
connection.
On rare systems where off_t is a 32-bit integer, this scenario is also feasible
with the "stco" atom.
The fix is to add checks which make sure data chunks referenced by each track
are within the mp4 file boundaries. Additionally a few more checks are added to
ensure mp4 file consistency and log errors.
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Wed, 26 Feb 2020 15:10:46 +0300 |
parents | ed599ea6c1f1 |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> typedef struct { /* the round robin data must be first */ ngx_http_upstream_rr_peer_data_t rrp; ngx_uint_t hash; u_char addrlen; u_char *addr; u_char tries; ngx_event_get_peer_pt get_rr_peer; } ngx_http_upstream_ip_hash_peer_data_t; static ngx_int_t ngx_http_upstream_init_ip_hash_peer(ngx_http_request_t *r, ngx_http_upstream_srv_conf_t *us); static ngx_int_t ngx_http_upstream_get_ip_hash_peer(ngx_peer_connection_t *pc, void *data); static char *ngx_http_upstream_ip_hash(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_command_t ngx_http_upstream_ip_hash_commands[] = { { ngx_string("ip_hash"), NGX_HTTP_UPS_CONF|NGX_CONF_NOARGS, ngx_http_upstream_ip_hash, 0, 0, NULL }, ngx_null_command }; static ngx_http_module_t ngx_http_upstream_ip_hash_module_ctx = { NULL, /* preconfiguration */ NULL, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL, /* merge server configuration */ NULL, /* create location configuration */ NULL /* merge location configuration */ }; ngx_module_t ngx_http_upstream_ip_hash_module = { NGX_MODULE_V1, &ngx_http_upstream_ip_hash_module_ctx, /* module context */ ngx_http_upstream_ip_hash_commands, /* module directives */ NGX_HTTP_MODULE, /* module type */ NULL, /* init master */ NULL, /* init module */ NULL, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static u_char ngx_http_upstream_ip_hash_pseudo_addr[3]; static ngx_int_t ngx_http_upstream_init_ip_hash(ngx_conf_t *cf, ngx_http_upstream_srv_conf_t *us) { if (ngx_http_upstream_init_round_robin(cf, us) != NGX_OK) { return NGX_ERROR; } us->peer.init = ngx_http_upstream_init_ip_hash_peer; return NGX_OK; } static ngx_int_t ngx_http_upstream_init_ip_hash_peer(ngx_http_request_t *r, ngx_http_upstream_srv_conf_t *us) { struct sockaddr_in *sin; #if (NGX_HAVE_INET6) struct sockaddr_in6 *sin6; #endif ngx_http_upstream_ip_hash_peer_data_t *iphp; iphp = ngx_palloc(r->pool, sizeof(ngx_http_upstream_ip_hash_peer_data_t)); if (iphp == NULL) { return NGX_ERROR; } r->upstream->peer.data = &iphp->rrp; if (ngx_http_upstream_init_round_robin_peer(r, us) != NGX_OK) { return NGX_ERROR; } r->upstream->peer.get = ngx_http_upstream_get_ip_hash_peer; switch (r->connection->sockaddr->sa_family) { case AF_INET: sin = (struct sockaddr_in *) r->connection->sockaddr; iphp->addr = (u_char *) &sin->sin_addr.s_addr; iphp->addrlen = 3; break; #if (NGX_HAVE_INET6) case AF_INET6: sin6 = (struct sockaddr_in6 *) r->connection->sockaddr; iphp->addr = (u_char *) &sin6->sin6_addr.s6_addr; iphp->addrlen = 16; break; #endif default: iphp->addr = ngx_http_upstream_ip_hash_pseudo_addr; iphp->addrlen = 3; } iphp->hash = 89; iphp->tries = 0; iphp->get_rr_peer = ngx_http_upstream_get_round_robin_peer; return NGX_OK; } static ngx_int_t ngx_http_upstream_get_ip_hash_peer(ngx_peer_connection_t *pc, void *data) { ngx_http_upstream_ip_hash_peer_data_t *iphp = data; time_t now; ngx_int_t w; uintptr_t m; ngx_uint_t i, n, p, hash; ngx_http_upstream_rr_peer_t *peer; ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0, "get ip hash peer, try: %ui", pc->tries); /* TODO: cached */ ngx_http_upstream_rr_peers_rlock(iphp->rrp.peers); if (iphp->tries > 20 || iphp->rrp.peers->single) { ngx_http_upstream_rr_peers_unlock(iphp->rrp.peers); return iphp->get_rr_peer(pc, &iphp->rrp); } now = ngx_time(); pc->cached = 0; pc->connection = NULL; hash = iphp->hash; for ( ;; ) { for (i = 0; i < (ngx_uint_t) iphp->addrlen; i++) { hash = (hash * 113 + iphp->addr[i]) % 6271; } w = hash % iphp->rrp.peers->total_weight; peer = iphp->rrp.peers->peer; p = 0; while (w >= peer->weight) { w -= peer->weight; peer = peer->next; p++; } n = p / (8 * sizeof(uintptr_t)); m = (uintptr_t) 1 << p % (8 * sizeof(uintptr_t)); if (iphp->rrp.tried[n] & m) { goto next; } ngx_log_debug2(NGX_LOG_DEBUG_HTTP, pc->log, 0, "get ip hash peer, hash: %ui %04XL", p, (uint64_t) m); ngx_http_upstream_rr_peer_lock(iphp->rrp.peers, peer); if (peer->down) { ngx_http_upstream_rr_peer_unlock(iphp->rrp.peers, peer); goto next; } if (peer->max_fails && peer->fails >= peer->max_fails && now - peer->checked <= peer->fail_timeout) { ngx_http_upstream_rr_peer_unlock(iphp->rrp.peers, peer); goto next; } if (peer->max_conns && peer->conns >= peer->max_conns) { ngx_http_upstream_rr_peer_unlock(iphp->rrp.peers, peer); goto next; } break; next: if (++iphp->tries > 20) { ngx_http_upstream_rr_peers_unlock(iphp->rrp.peers); return iphp->get_rr_peer(pc, &iphp->rrp); } } iphp->rrp.current = peer; pc->sockaddr = peer->sockaddr; pc->socklen = peer->socklen; pc->name = &peer->name; peer->conns++; if (now - peer->checked > peer->fail_timeout) { peer->checked = now; } ngx_http_upstream_rr_peer_unlock(iphp->rrp.peers, peer); ngx_http_upstream_rr_peers_unlock(iphp->rrp.peers); iphp->rrp.tried[n] |= m; iphp->hash = hash; return NGX_OK; } static char * ngx_http_upstream_ip_hash(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_http_upstream_srv_conf_t *uscf; uscf = ngx_http_conf_get_module_srv_conf(cf, ngx_http_upstream_module); if (uscf->peer.init_upstream) { ngx_conf_log_error(NGX_LOG_WARN, cf, 0, "load balancing method redefined"); } uscf->peer.init_upstream = ngx_http_upstream_init_ip_hash; uscf->flags = NGX_HTTP_UPSTREAM_CREATE |NGX_HTTP_UPSTREAM_WEIGHT |NGX_HTTP_UPSTREAM_MAX_CONNS |NGX_HTTP_UPSTREAM_MAX_FAILS |NGX_HTTP_UPSTREAM_FAIL_TIMEOUT |NGX_HTTP_UPSTREAM_DOWN; return NGX_CONF_OK; }