diff options
Diffstat (limited to 'jwt.c')
| -rw-r--r-- | jwt.c | 114 |
1 files changed, 69 insertions, 45 deletions
@@ -1,21 +1,17 @@ #include "jwt.h" -#include "base64.h" #include <dynstr.h> -#include <cjson/cJSON.h> -#include <openssl/evp.h> -#include <openssl/hmac.h> -#include <openssl/sha.h> +#include <sodium.h> #include <errno.h> #include <stddef.h> #include <stdlib.h> #include <stdio.h> #include <string.h> -static const char jwt_header[] = "{\"alg\": \"HS256\", \"typ\": \"JWT\"}"; +#define VARIANT sodium_base64_VARIANT_URLSAFE static char *get_payload(const char *const name) { - char *ret = NULL; + char *ret = NULL, *s = NULL; struct dynstr d; dynstr_init(&d); @@ -25,13 +21,27 @@ static char *get_payload(const char *const name) fprintf(stderr, "%s: dynstr_append name failed\n", __func__); goto end; } - else if (!(ret = base64_encode(d.str, d.len))) + + const size_t n = sodium_base64_encoded_len(d.len, VARIANT); + const unsigned char *const in = (const unsigned char *)d.str; + + if (!(s = malloc(n))) { - fprintf(stderr, "%s: base64 failed\n", __func__); + fprintf(stderr, "%s: malloc(3): %s\n", __func__, strerror(errno)); goto end; } + else if (!sodium_bin2base64(s, n, in, d.len, VARIANT)) + { + fprintf(stderr, "%s: sodium_bin2base64 failed\n", __func__); + goto end; + } + + ret = s; end: + if (!ret) + free(s); + dynstr_free(&d); return ret; } @@ -39,47 +49,66 @@ end: static char *get_hmac(const void *const buf, const size_t n, const void *const key, const size_t keyn) { - unsigned char hmac[SHA256_DIGEST_LENGTH]; - const EVP_MD *const md = EVP_sha256(); + unsigned char hmac[crypto_auth_hmacsha256_KEYBYTES]; char *ret = NULL; - if (!md) + if (keyn != crypto_auth_hmacsha256_KEYBYTES) { - fprintf(stderr, "%s: EVP_sha256 failed\n", __func__); - return NULL; + fprintf(stderr, "%s: invalid key size (%zu), expected %u\n", __func__, + n, crypto_auth_hmacsha256_KEYBYTES); + goto failure; } - else if (!HMAC(md, key, keyn, buf, n, hmac, NULL)) + else if (crypto_auth_hmacsha256(hmac, buf, n, key)) { fprintf(stderr, "%s: HMAC failed\n", __func__); - return NULL; + goto failure; + } + + const size_t b64n = sodium_base64_encoded_len(sizeof hmac, VARIANT); + + if (!(ret = malloc(b64n))) + { + fprintf(stderr, "%s: malloc(3): %s\n", __func__, strerror(errno)); + goto failure; } - else if (!(ret = base64_encode(hmac, sizeof hmac))) + else if (!sodium_bin2base64(ret, b64n, hmac, sizeof hmac, VARIANT)) { - fprintf(stderr, "%s: base64 failed\n", __func__); - return NULL; + fprintf(stderr, "%s: sodium_bin2base64 failed\n", __func__); + goto failure; } return ret; + +failure: + free(ret); + return NULL; } char *jwt_encode(const char *const name, const void *const key, const size_t n) { - char *ret = NULL; - char *const header = base64_encode(jwt_header, strlen(jwt_header)), - *const payload = get_payload(name), - *hmac = NULL; + static const char jwt_header[] = "{\"alg\": \"HS256\", \"typ\": \"JWT\"}"; struct dynstr jwt; + const size_t hlen = strlen(jwt_header), + sz = sodium_base64_encoded_len(hlen, VARIANT); + char *ret = NULL, *header = NULL, *hmac = NULL, + *const payload = get_payload(name); dynstr_init(&jwt); - if (!header) + if (!payload) { - fprintf(stderr, "%s: base64_encode header failed\n", __func__); + fprintf(stderr, "%s: get_payload failed\n", __func__); goto end; } - else if (!payload) + else if (!(header = malloc(sz))) { - fprintf(stderr, "%s: get_payload failed\n", __func__); + fprintf(stderr, "%s: malloc(3): %s\n", __func__, strerror(errno)); + goto end; + } + else if (!sodium_bin2base64(header, sz, (const unsigned char *)jwt_header, + hlen, VARIANT)) + { + fprintf(stderr, "%s: sodium_bin2base64 failed\n", __func__); goto end; } else if (dynstr_append(&jwt, "%s.%s", header, payload)) @@ -111,17 +140,17 @@ end: return ret; } -int jwt_check(const char *const jwt, const void *const key, const size_t n) +int jwt_check(const char *const jwt, const void *const key, + const size_t n) { const char *const p = strrchr(jwt, '.'); - const EVP_MD *const md = EVP_sha256(); - unsigned char hmac[SHA256_DIGEST_LENGTH]; - char *dhmac = NULL; - size_t hmaclen; + const unsigned char *const in = (const unsigned char *)jwt; + unsigned char hmac[crypto_auth_hmacsha256_KEYBYTES]; - if (!md) + if (n != crypto_auth_hmacsha256_KEYBYTES) { - fprintf(stderr, "%s: EVP_sha256 failed\n", __func__); + fprintf(stderr, "%s: invalid key size (%zu), expected %u\n", __func__, + n, crypto_auth_hmacsha256_KEYBYTES); return -1; } else if (!p) @@ -129,19 +158,14 @@ int jwt_check(const char *const jwt, const void *const key, const size_t n) fprintf(stderr, "%s: expected '.'\n", __func__); return 1; } - else if (!HMAC(md, key, n, (const unsigned char *)jwt, p - jwt, hmac, NULL)) + else if (sodium_base642bin(hmac, sizeof hmac, p + 1, strlen(p + 1), + NULL, NULL, NULL, VARIANT)) { - fprintf(stderr, "%s: HMAC failed\n", __func__); - return -1; - } - else if (!(dhmac = base64_decode(p + 1, &hmaclen))) - { - fprintf(stderr, "%s: base64_decode failed\n", __func__); + fprintf(stderr, "%s: sodium_base642bin failed\n", __func__); return 1; } + else if (crypto_auth_hmacsha256_verify(hmac, in, p - jwt, key)) + return 1; - const int r = memcmp(dhmac, hmac, hmaclen); - - free(dhmac); - return !!r; + return 0; } |
