view src/os/unix/ngx_solaris_sendfilev_chain.c @ 4162:fb1375e8b68c stable-1.0

Merging r4036, r4055, r4056, r4057, r4058, r4059, r4060, r4061, r4062, r4063, r4064: Ranges related fixes: The "max_ranges" directive. "max_ranges 0" disables ranges support at all, "max_ranges 1" allows the single range, etc. By default number of ranges is unlimited, to be precise, 2^31-1. If client requests more ranges than "max_ranges" permits, nginx disables ranges and returns just the source response. If total size of all ranges is greater than source response size, then nginx disables ranges and returns just the source response. This fix should not affect well-behaving applications but will defeat DoS attempts exploiting malicious byte ranges. Now unsatisfiable ranges are processed according to RFC 2616.
author Igor Sysoev <igor@sysoev.ru>
date Fri, 30 Sep 2011 14:06:08 +0000
parents 6f6d7ea70805
children d620f497c50f
line wrap: on
line source


/*
 * Copyright (C) Igor Sysoev
 */


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>


#if (NGX_TEST_BUILD_SOLARIS_SENDFILEV)

/* Solaris declarations */

typedef struct sendfilevec {
    int     sfv_fd;
    u_int   sfv_flag;
    off_t   sfv_off;
    size_t  sfv_len;
} sendfilevec_t;

#define SFV_FD_SELF  -2

static ssize_t sendfilev(int fd, const struct sendfilevec *vec,
    int sfvcnt, size_t *xferred)
{
    return -1;
}

#endif


#if (IOV_MAX > 64)
#define NGX_SENDFILEVECS  64
#else
#define NGX_SENDFILEVECS  IOV_MAX
#endif



ngx_chain_t *
ngx_solaris_sendfilev_chain(ngx_connection_t *c, ngx_chain_t *in, off_t limit)
{
    int             fd;
    u_char         *prev;
    off_t           size, send, prev_send, aligned, fprev;
    size_t          sent;
    ssize_t         n;
    ngx_int_t       eintr, complete;
    ngx_err_t       err;
    sendfilevec_t  *sfv, sfvs[NGX_SENDFILEVECS];
    ngx_array_t     vec;
    ngx_event_t    *wev;
    ngx_chain_t    *cl;

    wev = c->write;

    if (!wev->ready) {
        return in;
    }

    if (!c->sendfile) {
        return ngx_writev_chain(c, in, limit);
    }


    /* the maximum limit size is the maximum size_t value - the page size */

    if (limit == 0 || limit > (off_t) (NGX_MAX_SIZE_T_VALUE - ngx_pagesize)) {
        limit = NGX_MAX_SIZE_T_VALUE - ngx_pagesize;
    }


    send = 0;
    complete = 0;

    vec.elts = sfvs;
    vec.size = sizeof(sendfilevec_t);
    vec.nalloc = NGX_SENDFILEVECS;
    vec.pool = c->pool;

    for ( ;; ) {
        fd = SFV_FD_SELF;
        prev = NULL;
        fprev = 0;
        sfv = NULL;
        eintr = 0;
        sent = 0;
        prev_send = send;

        vec.nelts = 0;

        /* create the sendfilevec and coalesce the neighbouring bufs */

        for (cl = in; cl && vec.nelts < IOV_MAX && send < limit; cl = cl->next)
        {
            if (ngx_buf_special(cl->buf)) {
                continue;
            }

            if (ngx_buf_in_memory_only(cl->buf)) {
                fd = SFV_FD_SELF;

                size = cl->buf->last - cl->buf->pos;

                if (send + size > limit) {
                    size = limit - send;
                }

                if (prev == cl->buf->pos) {
                    sfv->sfv_len += (size_t) size;

                } else {
                    sfv = ngx_array_push(&vec);
                    if (sfv == NULL) {
                        return NGX_CHAIN_ERROR;
                    }

                    sfv->sfv_fd = SFV_FD_SELF;
                    sfv->sfv_flag = 0;
                    sfv->sfv_off = (off_t) (uintptr_t) cl->buf->pos;
                    sfv->sfv_len = (size_t) size;
                }

                prev = cl->buf->pos + (size_t) size;
                send += size;

            } else {
                prev = NULL;

                size = cl->buf->file_last - cl->buf->file_pos;

                if (send + size > limit) {
                    size = limit - send;

                    aligned = (cl->buf->file_pos + size + ngx_pagesize - 1)
                               & ~((off_t) ngx_pagesize - 1);

                    if (aligned <= cl->buf->file_last) {
                        size = aligned - cl->buf->file_pos;
                    }
                }

                if (fd == cl->buf->file->fd && fprev == cl->buf->file_pos) {
                    sfv->sfv_len += (size_t) size;

                } else {
                    sfv = ngx_array_push(&vec);
                    if (sfv == NULL) {
                        return NGX_CHAIN_ERROR;
                    }

                    fd = cl->buf->file->fd;
                    sfv->sfv_fd = fd;
                    sfv->sfv_flag = 0;
                    sfv->sfv_off = cl->buf->file_pos;
                    sfv->sfv_len = (size_t) size;
                }

                fprev = cl->buf->file_pos + size;
                send += size;
            }
        }

        n = sendfilev(c->fd, vec.elts, vec.nelts, &sent);

        if (n == -1) {
            err = ngx_errno;

            switch (err) {
            case NGX_EAGAIN:
                break;

            case NGX_EINTR:
                eintr = 1;
                break;

            default:
                wev->error = 1;
                ngx_connection_error(c, err, "sendfilev() failed");
                return NGX_CHAIN_ERROR;
            }

            ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, err,
                          "sendfilev() sent only %uz bytes", sent);
        }

        ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0,
                       "sendfilev: %z %z", n, sent);

        if (send - prev_send == (off_t) sent) {
            complete = 1;
        }

        c->sent += sent;

        for (cl = in; cl; cl = cl->next) {

            if (ngx_buf_special(cl->buf)) {
                continue;
            }

            if (sent == 0) {
                break;
            }

            size = ngx_buf_size(cl->buf);

            if ((off_t) sent >= size) {
                sent = (size_t) ((off_t) sent - size);

                if (ngx_buf_in_memory(cl->buf)) {
                    cl->buf->pos = cl->buf->last;
                }

                if (cl->buf->in_file) {
                    cl->buf->file_pos = cl->buf->file_last;
                }

                continue;
            }

            if (ngx_buf_in_memory(cl->buf)) {
                cl->buf->pos += sent;
            }

            if (cl->buf->in_file) {
                cl->buf->file_pos += sent;
            }

            break;
        }

        if (eintr) {
            continue;
        }

        if (!complete) {
            wev->ready = 0;
            return cl;
        }

        if (send >= limit || cl == NULL) {
            return cl;
        }

        in = cl;
    }
}