Line data    Source code

       1             : #ifndef DDEBUG
       2             : #define DDEBUG 0
       3             : #endif
       4             : #include "ddebug.h"
       5             : 
       6             : #include <ndk.h>
       7             : 
       8             : #include "ngx_http_set_hmac.h"
       9             : #include <openssl/evp.h>
      10             : #include <openssl/hmac.h>
      11             : 
      12             : 
      13             : /* this function's implementation is partly borrowed from
      14             :  * https://github.com/anomalizer/ngx_aws_auth */
      15             : ngx_int_t
      16           0 : ngx_http_set_misc_set_hmac_sha1(ngx_http_request_t *r, ngx_str_t *res,
      17             :     ngx_http_variable_value_t *v)
      18             : {
      19             :     ngx_http_variable_value_t   *secret, *string_to_sign;
      20           0 :     unsigned int                 md_len = 0;
      21             :     unsigned char                md[EVP_MAX_MD_SIZE];
      22             :     const EVP_MD                *evp_md;
      23             : 
      24           0 :     evp_md = EVP_sha1();
      25             : 
      26           0 :     secret = v;
      27           0 :     string_to_sign = v + 1;
      28             : 
      29             :     dd("secret=%.*s, string_to_sign=%.*s", (int) secret->len, secret->data,
      30             :        (int) string_to_sign->len, string_to_sign->data);
      31             : 
      32           0 :     HMAC(evp_md, secret->data, secret->len, string_to_sign->data,
      33           0 :          string_to_sign->len, md, &md_len);
      34             : 
      35             :     /* defensive test if there is something wrong with openssl */
      36           0 :     if (md_len == 0 || md_len > EVP_MAX_MD_SIZE) {
      37           0 :         res->len = 0;
      38           0 :         return NGX_ERROR;
      39             :     }
      40             : 
      41           0 :     res->len = md_len;
      42           0 :     ndk_palloc_re(res->data, r->pool, md_len);
      43             : 
      44           0 :     ngx_memcpy(res->data,
      45             :                &md,
      46             :                md_len);
      47             : 
      48           0 :     return NGX_OK;
      49             : }
      50             :