diff options
| -rw-r--r-- | CMakeLists.txt | 2 | ||||
| -rw-r--r-- | curl-wrap.c | 210 | ||||
| -rw-r--r-- | curl-wrap.h | 45 | ||||
| -rw-r--r-- | escape.c | 428 | ||||
| -rw-r--r-- | escape.h | 23 |
5 files changed, 707 insertions, 1 deletions
diff --git a/CMakeLists.txt b/CMakeLists.txt index fe260fa..c294717 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -23,7 +23,7 @@ PROJECT_TARGET_ADD(afb-utilities) # Define targets - ADD_LIBRARY(${TARGET_NAME} STATIC wrap-json.c filescan-utils.c) + ADD_LIBRARY(${TARGET_NAME} STATIC curl-wrap.c escape.c wrap-json.c filescan-utils.c) # Library properties SET_TARGET_PROPERTIES(${TARGET_NAME} PROPERTIES diff --git a/curl-wrap.c b/curl-wrap.c new file mode 100644 index 0000000..3c566a3 --- /dev/null +++ b/curl-wrap.c @@ -0,0 +1,210 @@ +/* + * Copyright (C) 2015, 2016 "IoT.bzh" + * Author: José Bollo <jose.bollo@iot.bzh> + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +#define _GNU_SOURCE + +#include <stdint.h> +#include <stdlib.h> +#include <string.h> +#include <errno.h> + +#include <curl/curl.h> + +#include "curl-wrap.h" +#include "escape.h" + + +/* internal representation of buffers */ +struct buffer { + size_t size; + char *data; +}; + +/* write callback for filling buffers with the response */ +static size_t write_callback(char *ptr, size_t size, size_t nmemb, void *userdata) +{ + struct buffer *buffer = userdata; + size_t sz = size * nmemb; + size_t old_size = buffer->size; + size_t new_size = old_size + sz; + char *data = realloc(buffer->data, new_size + 1); + if (!data) + return 0; + memcpy(&data[old_size], ptr, sz); + data[new_size] = 0; + buffer->size = new_size; + buffer->data = data; + return sz; +} + +/* + * Perform the CURL operation for 'curl' and put the result in + * memory. If 'result' isn't NULL it receives the returned content + * that then must be freed. If 'size' isn't NULL, it receives the + * size of the returned content. Note that if not NULL, the real + * content is one byte greater than the read size and the last byte + * zero. This facility allows to handle the returned content as a + * null terminated C-string. + */ +int curl_wrap_perform(CURL *curl, char **result, size_t *size) +{ + int rc; + struct buffer buffer; + CURLcode code; + + /* init tthe buffer */ + buffer.size = 0; + buffer.data = NULL; + + /* Perform the request, res will get the return code */ + curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_callback); + curl_easy_setopt(curl, CURLOPT_WRITEDATA, &buffer); + + /* Perform the request, res will get the return code */ + code = curl_easy_perform(curl); + rc = code == CURLE_OK; + + /* Check for no errors */ + if (rc) { + /* no error */ + if (size) + *size = buffer.size; + if (result) + *result = buffer.data; + else + free(buffer.data); + } else { + /* had error */ + if (size) + *size = 0; + if (result) + *result = NULL; + free(buffer.data); + } + + return rc; +} + +void curl_wrap_do(CURL *curl, void (*callback)(void *closure, int status, CURL *curl, const char *result, size_t size), void *closure) +{ + int rc; + char *result; + size_t size; + char errbuf[CURL_ERROR_SIZE]; + + curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, errbuf); + rc = curl_wrap_perform(curl, &result, &size); + if (rc) + callback(closure, rc, curl, result, size); + else + callback(closure, rc, curl, errbuf, 0); + free(result); + curl_easy_cleanup(curl); +} + +int curl_wrap_content_type_is(CURL *curl, const char *value) +{ + char *actual; + CURLcode code; + + code = curl_easy_getinfo(curl, CURLINFO_CONTENT_TYPE, &actual); + if (code != CURLE_OK || !actual) + return 0; + + return !strncasecmp(actual, value, strcspn(actual, "; ")); +} + +CURL *curl_wrap_prepare_get_url(const char *url) +{ + CURL *curl; + CURLcode code; + + curl = curl_easy_init(); + if(curl) { + code = curl_easy_setopt(curl, CURLOPT_URL, url); + if (code == CURLE_OK) + return curl; + curl_easy_cleanup(curl); + } + return NULL; +} + +CURL *curl_wrap_prepare_get(const char *base, const char *path, const char * const *args) +{ + CURL *res; + char *url; + + url = escape_url(base, path, args, NULL); + res = url ? curl_wrap_prepare_get_url(url) : NULL; + free(url); + return res; +} + +int curl_wrap_add_header(CURL *curl, const char *header) +{ + int rc; + struct curl_slist *list; + + list = curl_slist_append(NULL, header); + rc = list ? curl_easy_setopt(curl, CURLOPT_HTTPHEADER, list) == CURLE_OK : 0; +/* + curl_slist_free_all(list); +*/ + return rc; +} + +int curl_wrap_add_header_value(CURL *curl, const char *name, const char *value) +{ + char *h; + int rc; + + rc = asprintf(&h, "%s: %s", name, value); + rc = rc < 0 ? 0 : curl_wrap_add_header(curl, h); + free(h); + return rc; +} + + +CURL *curl_wrap_prepare_post_url_data(const char *url, const char *datatype, const char *data, size_t szdata) +{ + CURL *curl; + + curl = curl_easy_init(); + if (curl + && CURLE_OK == curl_easy_setopt(curl, CURLOPT_URL, url) + && (!szdata || CURLE_OK == curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE, szdata)) + && CURLE_OK == curl_easy_setopt(curl, CURLOPT_POSTFIELDS, data) + && (!datatype || curl_wrap_add_header_value(curl, "content-type", datatype))) + return curl; + curl_easy_cleanup(curl); + return NULL; +} + +CURL *curl_wrap_prepare_post(const char *base, const char *path, const char * const *args) +{ + CURL *res; + char *url; + char *data; + size_t szdata; + + url = escape_url(base, path, NULL, NULL); + data = escape_args(args, &szdata); + res = url ? curl_wrap_prepare_post_url_data(url, NULL, data, szdata) : NULL; + free(url); + return res; +} + +/* vim: set colorcolumn=80: */ diff --git a/curl-wrap.h b/curl-wrap.h new file mode 100644 index 0000000..2e44f47 --- /dev/null +++ b/curl-wrap.h @@ -0,0 +1,45 @@ +/* + * Copyright (C) 2015, 2016 "IoT.bzh" + * Author: José Bollo <jose.bollo@iot.bzh> + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + * + */ + +#pragma once + +#include <curl/curl.h> + +extern char *curl_wrap_url (const char *base, const char *path, + const char *const *query, size_t * size); + +extern int curl_wrap_perform (CURL * curl, char **result, size_t * size); + +extern void curl_wrap_do(CURL *curl, void (*callback)(void *closure, int status, CURL *curl, const char *result, size_t size), void *closure); + +extern int curl_wrap_content_type_is (CURL * curl, const char *value); + +extern CURL *curl_wrap_prepare_get_url(const char *url); + +extern CURL *curl_wrap_prepare_get(const char *base, const char *path, const char * const *args); + +extern CURL *curl_wrap_prepare_post_url_data(const char *url, const char *datatype, const char *data, size_t szdata); + +extern CURL *curl_wrap_prepare_post(const char *base, const char *path, const char * const *args); + +extern int curl_wrap_add_header(CURL *curl, const char *header); + +extern int curl_wrap_add_header_value(CURL *curl, const char *name, const char *value); + +/* vim: set colorcolumn=80: */ + diff --git a/escape.c b/escape.c new file mode 100644 index 0000000..3bb25c2 --- /dev/null +++ b/escape.c @@ -0,0 +1,428 @@ +/* + * Copyright (C) 2015, 2016 "IoT.bzh" + * Author: José Bollo <jose.bollo@iot.bzh> + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +#define _GNU_SOURCE + +#include <stdint.h> +#include <stdlib.h> +#include <string.h> + +/* + * Test if 'c' is to be escaped or not. + * Any character that is not in [-.0-9A-Z_a-z~] + * must be escaped. + * Note that space versus + is not managed here. + */ +static inline int should_escape(char c) +{ +/* ASCII CODES OF UNESCAPED CHARS +car hx/oct idx +'-' 2d/055 1 +'.' 2e/056 2 +'0' 30/060 3 +... .. +'9' 39/071 12 +'A' 41/101 13 +... .. +'Z' 5a/132 38 +'_' 5f/137 39 +'a' 61/141 40 +... .. +'z' 7a/172 65 +'~' 7e/176 66 +*/ + /* [-.0-9A-Z_a-z~] */ + if (c <= 'Z') { + /* [-.0-9A-Z] */ + if (c < '0') { + /* [-.] */ + return c != '-' && c != '.'; + } else { + /* [0-9A-Z] */ + return c < 'A' && c > '9'; + } + } else { + /* [_a-z~] */ + if (c <= 'z') { + /* [_a-z] */ + return c < 'a' && c != '_'; + } else { + /* [~] */ + return c != '~'; + } + } +} + +/* + * returns the ASCII char for the hexadecimal + * digit of the binary value 'f'. + * returns 0 if f isn't in [0 ... 15]. + */ +static inline char bin2hex(int f) +{ + if ((f & 15) != f) + f = 0; + else if (f < 10) + f += '0'; + else + f += 'A' - 10; + return (char)f; +} + +/* + * returns the binary value for the hexadecimal + * digit whose char is 'c'. + * returns -1 if c isn't i n[0-9A-Fa-f] + */ +static inline int hex2bin(char c) +{ + /* [0-9A-Fa-f] */ + if (c <= 'F') { + /* [0-9A-F] */ + if (c <= '9') { + /* [0-9] */ + if (c >= '0') { + return (int)(c - '0'); + } + } else if (c >= 'A') { + /* [A-F] */ + return (int)(c - ('A' - 10)); + } + } else { + /* [a-f] */ + if (c >= 'a' && c <= 'f') { + return (int)(c - ('a' - 10)); + } + } + return -1; +} + +/* + * returns the length that will have the text 'itext' of length + * 'ilen' when escaped. When 'ilen' == 0, strlen is used to + * compute the size of 'itext'. + */ +static size_t escaped_length(const char *itext, size_t ilen) +{ + char c; + size_t i, r; + + if (!ilen) + ilen = strlen(itext); + c = itext[i = r = 0]; + while (i < ilen) { + r += c != ' ' && should_escape(c) ? 3 : 1; + c = itext[++i]; + } + return r; +} + +/* + * Escapes the text 'itext' of length 'ilen'. + * When 'ilen' == 0, strlen is used to compute the size of 'itext'. + * The escaped text is put in 'otext' of length 'olen'. + * Returns the length of the escaped text (it can be greater than 'olen'). + * When 'olen' is greater than the needed length, an extra null terminator + * is appened to the escaped string. + */ +static size_t escape_to(const char *itext, size_t ilen, char *otext, size_t olen) +{ + char c; + size_t i, r; + + if (!ilen) + ilen = strlen(itext); + c = itext[i = r = 0]; + while (i < ilen) { + if (c == ' ') + c = '+'; + else if (should_escape(c)) { + if (r < olen) + otext[r] = '%'; + r++; + if (r < olen) + otext[r] = bin2hex((c >> 4) & 15); + r++; + c = bin2hex(c & 15); + } + if (r < olen) + otext[r] = c; + r++; + c = itext[++i]; + } + if (r < olen) + otext[r] = 0; + return r; +} + +/* + * returns the length of 'itext' of length 'ilen' that can be unescaped. + * compute the size of 'itext' when 'ilen' == 0. + */ +static size_t unescapable_length(const char *itext, size_t ilen) +{ + char c; + size_t i; + + c = itext[i = 0]; + while (i < ilen) { + if (c != '%') + i++; + else { + if (i + 3 > ilen + || hex2bin(itext[i + 1]) < 0 + || hex2bin(itext[i + 2]) < 0) + break; + i += 3; + } + c = itext[i]; + } + return i; +} + +/* + * returns the length that will have the text 'itext' of length + * 'ilen' when escaped. When 'ilen' == 0, strlen is used to + * compute the size of 'itext'. + */ +static size_t unescaped_length(const char *itext, size_t ilen) +{ + char c; + size_t i, r; + + c = itext[i = r = 0]; + while (i < ilen) { + i += (size_t)(1 + ((c == '%') << 1)); + r++; + c = itext[i]; + } + return r; +} + +static size_t unescape_to(const char *itext, size_t ilen, char *otext, size_t olen) +{ + char c; + size_t i, r; + int h, l; + + ilen = unescapable_length(itext, ilen); + c = itext[i = r = 0]; + while (i < ilen) { + if (c != '%') { + if (c == '+') + c = ' '; + i++; + } else { + if (i + 2 >= ilen) + break; + h = hex2bin(itext[i + 1]); + l = hex2bin(itext[i + 2]); + c = (char)((h << 4) | l); + i += 3; + } + if (r < olen) + otext[r] = c; + r++; + c = itext[i]; + } + if (r < olen) + otext[r] = 0; + return r; +} + +/* create an url */ +char *escape_url(const char *base, const char *path, const char * const *args, size_t *length) +{ + int i; + size_t lb, lp, lq, l, L; + const char *null; + char *result; + + /* ensure args */ + if (!args) { + null = NULL; + args = &null; + } + + /* compute lengths */ + lb = base ? strlen(base) : 0; + lp = path ? strlen(path) : 0; + lq = 0; + i = 0; + while (args[i]) { + lq += 1 + escaped_length(args[i], strlen(args[i])); + i++; + if (args[i]) + lq += 1 + escaped_length(args[i], strlen(args[i])); + i++; + } + + /* allocation */ + L = lb + lp + lq + 1; + result = malloc(L + 1); + if (result) { + /* make the resulting url */ + l = lb; + if (lb) { + memcpy(result, base, lb); + if (result[l - 1] != '/' && path && path[0] != '/') + result[l++] = '/'; + } + if (lp) { + memcpy(result + l, path, lp); + l += lp; + } + i = 0; + while (args[i]) { + if (i) { + result[l++] = '&'; + } else if (base || path) { + result[l] = memchr(result, '?', l) ? '&' : '?'; + l++; + } + l += escape_to(args[i], strlen(args[i]), result + l, L - l); + i++; + if (args[i]) { + result[l++] = '='; + l += escape_to(args[i], strlen(args[i]), result + l, L - l); + } + i++; + } + result[l] = 0; + if (length) + *length = l; + } + return result; +} + +char *escape_args(const char * const *args, size_t *length) +{ + return escape_url(NULL, NULL, args, length); +} + +const char **unescape_args(const char *args) +{ + const char **r, **q; + char c, *p; + size_t j, z, l, n, lt; + + lt = n = 0; + if (args[0]) { + z = 0; + do { + l = strcspn(&args[z], "&="); + j = 1 + unescaped_length(&args[z], l); + lt += j; + z += l; + c = args[z++]; + if (c == '=') { + l = strcspn(&args[z], "&"); + j = 1 + unescaped_length(&args[z], l); + lt += j; + z += l; + c = args[z++]; + } + n++; + } while(c); + } + + l = lt + (2 * n + 1) * sizeof(char *); + r = malloc(l); + if (!r) + return r; + + q = r; + p = (void*)&r[2 * n + 1]; + if (args[0]) { + z = 0; + do { + q[0] = p; + l = strcspn(&args[z], "&="); + j = 1 + unescape_to(&args[z], l, p, lt); + lt -= j; + p += j; + z += l; + c = args[z++]; + if (c != '=') + q[1] = NULL; + else { + q[1] = p; + l = strcspn(&args[z], "&"); + j = 1 + unescape_to(&args[z], l, p, lt); + lt -= j; + p += j; + z += l; + c = args[z++]; + } + q = &q[2]; + } while(c); + } + q[0] = NULL; + return r; +} + +char *escape(const char *text, size_t textlen, size_t *reslength) +{ + size_t len; + char *result; + + len = 1 + escaped_length(text, textlen); + result = malloc(len); + if (result) + escape_to(text, textlen, result, len); + if (reslength) + *reslength = len - 1; + return result; +} + +char *unescape(const char *text, size_t textlen, size_t *reslength) +{ + size_t len; + char *result; + + len = 1 + unescaped_length(text, textlen); + result = malloc(len); + if (result) + unescape_to(text, textlen, result, len); + if (reslength) + *reslength = len - 1; + return result; +} + +#if 1 +#include <stdio.h> +int main(int ac, char **av) +{ + int i; + char *x = escape_args((void*)++av, NULL); + char *y = escape(x, strlen(x), NULL); + char *z = unescape(y, strlen(y), NULL); + const char **v = unescape_args(x); + + printf("%s\n%s\n%s\n", x, y, z); + free(x); + free(y); + free(z); + i = 0; + while(v[i]) { + printf("%s=%s / %s=%s\n", av[i], av[i+1], v[i], v[i+1]); + i += 2; + } + free(v); + return 0; +} +#endif +/* vim: set colorcolumn=80: */ diff --git a/escape.h b/escape.h new file mode 100644 index 0000000..7d548db --- /dev/null +++ b/escape.h @@ -0,0 +1,23 @@ +/* + * Copyright (C) 2017 "IoT.bzh" + * Author: José Bollo <jose.bollo@iot.bzh> + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +#pragma once + +extern char *escape_url(const char *base, const char *path, const char * const *args, size_t *length); +extern char *escape_args(const char * const *args, size_t *length); +extern const char **unescape_args(const char *args); + +/* vim: set colorcolumn=80: */ |