path: root/src/lib/abrt_curl.c

/*
    Copyright (C) 2010  ABRT team
    Copyright (C) 2010  RedHat Inc

    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 2 of the License, 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.,
    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "abrtlib.h"
#include "abrt_curl.h"

/*
 * Utility functions
 */
CURL* xcurl_easy_init()
{
    CURL* curl = curl_easy_init();
    if (!curl)
    {
        error_msg_and_die("Can't create curl handle");
    }
    return curl;
}

static char*
check_curl_error(CURLcode err, const char* msg)
{
    if (err)
        return xasprintf("%s: %s", msg, curl_easy_strerror(err));
    return NULL;
}

static void
die_if_curl_error(CURLcode err)
{
    if (err) {
        char *msg = check_curl_error(err, "curl");
        error_msg_and_die("%s", msg);
    }
}

static void
xcurl_easy_setopt_ptr(CURL *handle, CURLoption option, const void *parameter)
{
    CURLcode err = curl_easy_setopt(handle, option, parameter);
    if (err) {
        char *msg = check_curl_error(err, "curl");
        error_msg_and_die("%s", msg);
    }
}
static inline void
xcurl_easy_setopt_long(CURL *handle, CURLoption option, long parameter)
{
    xcurl_easy_setopt_ptr(handle, option, (void*)parameter);
}

/*
 * post_state utility functions
 */

abrt_post_state_t *new_abrt_post_state(int flags)
{
    abrt_post_state_t *state = (abrt_post_state_t *)xzalloc(sizeof(*state));
    state->flags = flags;
    return state;
}

void free_abrt_post_state(abrt_post_state_t *state)
{
    char **headers = state->headers;
    if (headers)
    {
        while (*headers)
            free(*headers++);
        free(state->headers);
    }
    free(state->curl_error_msg);
    free(state->body);
    free(state);
}

char *find_header_in_abrt_post_state(abrt_post_state_t *state, const char *str)
{
    char **headers = state->headers;
    if (headers)
    {
        unsigned len = strlen(str);
        while (*headers)
        {
            if (strncmp(*headers, str, len) == 0)
                return skip_whitespace(*headers + len);
            headers++;
        }
    }
    return NULL;
}

/*
 * abrt_post: perform HTTP POST transaction
 */

/* "save headers" callback */
static size_t
save_headers(void *buffer_pv, size_t count, size_t nmemb, void *ptr)
{
    abrt_post_state_t* state = (abrt_post_state_t*)ptr;
    size_t size = count * nmemb;

    char *h = xstrndup((char*)buffer_pv, size);
    strchrnul(h, '\r')[0] = '\0';
    strchrnul(h, '\n')[0] = '\0';

    unsigned cnt = state->header_cnt;

    /* Check for the case when curl follows a redirect:
     * header 0: 'HTTP/1.1 301 Moved Permanently'
     * header 1: 'Connection: close'
     * header 2: 'Location: NEW_URL'
     * header 3: ''
     * header 0: 'HTTP/1.1 200 OK' <-- we need to forget all hdrs and start anew
     */
    if (cnt != 0
     && strncmp(h, "HTTP/", 5) == 0
     && state->headers[cnt-1][0] == '\0' /* prev header is an empty string */
    ) {
        char **headers = state->headers;
        if (headers)
        {
            while (*headers)
                free(*headers++);
        }
        cnt = 0;
    }

    VERB3 log("save_headers: header %d: '%s'", cnt, h);
    state->headers = (char**)xrealloc(state->headers, (cnt+2) * sizeof(state->headers[0]));
    state->headers[cnt] = h;
    state->header_cnt = ++cnt;
    state->headers[cnt] = NULL;

    return size;
}

/* "read local data from a file" callback */
static size_t fread_with_reporting(void *ptr, size_t size, size_t nmemb, void *userdata)
{
    static time_t last_t; // hack

    FILE *fp = (FILE*)userdata;
    time_t t = time(NULL);

    // Report current file position every 16 seconds
    if (!(t & 0xf) && last_t != t)
    {
        last_t = t;
        off_t cur_pos = ftello(fp);
        fseeko(fp, 0, SEEK_END);
        off_t sz = ftello(fp);
        fseeko(fp, cur_pos, SEEK_SET);
        log(_("Uploaded: %llu of %llu kbytes"),
                (unsigned long long)cur_pos / 1024,
                (unsigned long long)sz / 1024);
    }

    return fread(ptr, size, nmemb, fp);
}

int
abrt_post(abrt_post_state_t *state,
                const char *url,
                const char *content_type,
                const char *data,
                off_t data_size)
{
    CURLcode curl_err;
    long response_code;
    abrt_post_state_t localstate;

    VERB3 log("abrt_post('%s','%s')", url, data);

    if (!state)
    {
        memset(&localstate, 0, sizeof(localstate));
        state = &localstate;
    }

    state->http_resp_code = response_code = -1;

    CURL *handle = xcurl_easy_init();

    // Buffer[CURL_ERROR_SIZE] curl stores human readable error messages in.
    // This may be more helpful than just return code from curl_easy_perform.
    // curl will need it until curl_easy_cleanup.
    state->errmsg[0] = '\0';
    xcurl_easy_setopt_ptr(handle, CURLOPT_ERRORBUFFER, state->errmsg);
    // "Display a lot of verbose information about its operations.
    // Very useful for libcurl and/or protocol debugging and understanding.
    // The verbose information will be sent to stderr, or the stream set
    // with CURLOPT_STDERR"
    //xcurl_easy_setopt_long(handle, CURLOPT_VERBOSE, 1);
    // Shut off the built-in progress meter completely
    xcurl_easy_setopt_long(handle, CURLOPT_NOPROGRESS, 1);

    // TODO: do we need to check for CURLE_URL_MALFORMAT error *here*,
    // not in curl_easy_perform?
    xcurl_easy_setopt_ptr(handle, CURLOPT_URL, url);

    // Auth if configured
    if (state->username) {
        // bitmask of allowed auth methods
        xcurl_easy_setopt_long(handle, CURLOPT_HTTPAUTH, CURLAUTH_BASIC);
        xcurl_easy_setopt_ptr(handle, CURLOPT_USERNAME, state->username);
        xcurl_easy_setopt_ptr(handle, CURLOPT_PASSWORD, (state->password ? state->password : ""));
    }

    // Do a regular HTTP post. This also makes curl use
    // a "Content-Type: application/x-www-form-urlencoded" header.
    // (This is by far the most commonly used POST method).
    xcurl_easy_setopt_long(handle, CURLOPT_POST, 1);
    // Supply POST data...
    struct curl_httppost* post = NULL;
    struct curl_httppost* last = NULL;
    FILE* data_file = NULL;
    if (data_size == ABRT_POST_DATA_FROMFILE) {
        // ...from a file
        data_file = fopen(data, "r");
        if (!data_file)
//FIXME:
            perror_msg_and_die("can't open '%s'", data);
        xcurl_easy_setopt_ptr(handle, CURLOPT_READDATA, data_file);
        // Want to use custom read function
        xcurl_easy_setopt_ptr(handle, CURLOPT_READFUNCTION, (const void*)fread_with_reporting);
    } else if (data_size == ABRT_POST_DATA_FROMFILE_AS_FORM_DATA) {
        // ...from a file, in multipart/formdata format
        const char *basename = strrchr(data, '/');
        if (basename) basename++;
        else basename = data;
#if 0
	// Simple way, without custom reader function
        CURLFORMcode curlform_err = curl_formadd(&post, &last,
                        CURLFORM_PTRNAME, "file", // element name
                        CURLFORM_FILE, data, // filename to read from
                        CURLFORM_CONTENTTYPE, content_type,
                        CURLFORM_FILENAME, basename, // filename to put in the form
                        CURLFORM_END);
#else
        data_file = fopen(data, "r");
        if (!data_file)
//FIXME:
            perror_msg_and_die("can't open '%s'", data);
        // Want to use custom read function
        xcurl_easy_setopt_ptr(handle, CURLOPT_READFUNCTION, (const void*)fread_with_reporting);
        // Need to know file size
        fseeko(data_file, 0, SEEK_END);
        off_t sz = ftello(data_file);
        fseeko(data_file, 0, SEEK_SET);
        // Create formdata
        CURLFORMcode curlform_err = curl_formadd(&post, &last,
                        CURLFORM_PTRNAME, "file", // element name
                        // use CURLOPT_READFUNCTION for reading, pass data_file as its last param:
                        CURLFORM_STREAM, data_file,
                        CURLFORM_CONTENTSLENGTH, (long)sz, // a must if we use CURLFORM_STREAM option
                        CURLFORM_CONTENTTYPE, content_type,
                        CURLFORM_FILENAME, basename, // filename to put in the form
                        CURLFORM_END);
#endif
        if (curlform_err != 0)
//FIXME:
            error_msg_and_die("out of memory or read error (curl_formadd error code: %d)", (int)curlform_err);
        xcurl_easy_setopt_ptr(handle, CURLOPT_HTTPPOST, post);
    } else {
        // .. from a blob in memory
        xcurl_easy_setopt_ptr(handle, CURLOPT_POSTFIELDS, data);
        // note1: if data_size == ABRT_POST_DATA_STRING == -1, curl will use strlen(data)
        xcurl_easy_setopt_long(handle, CURLOPT_POSTFIELDSIZE, data_size);
        // note2: CURLOPT_POSTFIELDSIZE_LARGE can't be used: xcurl_easy_setopt_long()
        // truncates data_size on 32-bit arch. Need xcurl_easy_setopt_long_long()?
        // Also, I'm not sure CURLOPT_POSTFIELDSIZE_LARGE special-cases -1.
    }
    // Override "Content-Type:"
    struct curl_slist *httpheader_list = NULL;
    if (data_size != ABRT_POST_DATA_FROMFILE_AS_FORM_DATA)
    {
        char *content_type_header = xasprintf("Content-Type: %s", content_type);
        // Note: curl_slist_append() copies content_type_header
        httpheader_list = curl_slist_append(httpheader_list, content_type_header);
        if (!httpheader_list)
            error_msg_and_die("out of memory");
        free(content_type_header);
        xcurl_easy_setopt_ptr(handle, CURLOPT_HTTPHEADER, httpheader_list);
    }

// Disabled: was observed to also handle "305 Use proxy" redirect,
// apparently with POST->GET remapping - which server didn't like at all.
// Attempted to suppress remapping on 305 using CURLOPT_POSTREDIR of -1,
// but it still did not work.
#if 0
    // Please handle 301/302 redirects for me
    xcurl_easy_setopt_long(handle, CURLOPT_FOLLOWLOCATION, 1);
    xcurl_easy_setopt_long(handle, CURLOPT_MAXREDIRS, 10);
    // Bitmask to control how libcurl acts on redirects after POSTs.
    // Bit 0 set (value CURL_REDIR_POST_301) makes libcurl
    // not convert POST requests into GET requests when following
    // a 301 redirection. Bit 1 (value CURL_REDIR_POST_302) makes libcurl
    // maintain the request method after a 302 redirect.
    // CURL_REDIR_POST_ALL is a convenience define that sets both bits.
    // The non-RFC behaviour is ubiquitous in web browsers, so the library
    // does the conversion by default to maintain consistency.
    // However, a server may require a POST to remain a POST.
    xcurl_easy_setopt_long(handle, CURLOPT_POSTREDIR, -1L /*CURL_REDIR_POST_ALL*/ );
#endif

    // Prepare for saving information
    if (state->flags & ABRT_POST_WANT_HEADERS)
    {
        xcurl_easy_setopt_ptr(handle, CURLOPT_HEADERFUNCTION, (void*)save_headers);
        xcurl_easy_setopt_ptr(handle, CURLOPT_WRITEHEADER, state);
    }
    FILE* body_stream = NULL;
    if (state->flags & ABRT_POST_WANT_BODY)
    {
        body_stream = open_memstream(&state->body, &state->body_size);
        if (!body_stream)
            error_msg_and_die("out of memory");
        xcurl_easy_setopt_ptr(handle, CURLOPT_WRITEDATA, body_stream);
    }
    if (!(state->flags & ABRT_POST_WANT_SSL_VERIFY))
    {
        xcurl_easy_setopt_long(handle, CURLOPT_SSL_VERIFYPEER, 0);
        xcurl_easy_setopt_long(handle, CURLOPT_SSL_VERIFYHOST, 0);
    }

    // This is the place where everything happens.
    // Here errors are not limited to "out of memory", can't just die.
    curl_err = curl_easy_perform(handle);
    if (curl_err)
    {
        VERB2 log("curl_easy_perform: error %d", (int)curl_err);
        if (state->flags & ABRT_POST_WANT_ERROR_MSG)
        {
            state->curl_error_msg = check_curl_error(curl_err, "curl_easy_perform");
            VERB3 log("curl_easy_perform: error_msg: %s", state->curl_error_msg);
        }
        goto ret;
    }

    // Headers/body are already saved (if requested), extract more info
    curl_err = curl_easy_getinfo(handle, CURLINFO_RESPONSE_CODE, &response_code);
    die_if_curl_error(curl_err);
    state->http_resp_code = response_code;
    VERB3 log("after curl_easy_perform: http code %ld body:'%s'", response_code, state->body);

 ret:
    curl_easy_cleanup(handle);
    if (httpheader_list)
        curl_slist_free_all(httpheader_list);
    if (body_stream)
        fclose(body_stream);
    if (data_file)
        fclose(data_file);
    if (post)
        curl_formfree(post);

    return response_code;
}