cgmnlm

Unnamed repository; edit this file 'description' to name the repository.
git clone git://code.clttr.info/cgmnlm.git
Log | Files | Refs | README | LICENSE

commit fc0bf889a3e5ce270600811875ef9a50729c4135
parent e7b2013160db902df5b833ff2e49eaff90807514
Author: Drew DeVault <sir@cmpwn.com>
Date:   Thu,  4 Mar 2021 10:59:19 -0500

all: rewrite with BearSSL rather than OpenSSL

Diffstat:
MREADME.md | 2+-
Mconfig.sh | 4++--
Minclude/gmni/gmni.h | 26+++++++++++++++-----------
Minclude/gmni/tofu.h | 24++++++++++++++++++------
Minclude/util.h | 2++
Msrc/client.c | 160+++++++++++++++++++++++++++++++++++++------------------------------------------
Msrc/gmni.c | 19++++++-------------
Msrc/gmnlm.c | 79+++++++++++++++++++++++++++++++++++++++++++++----------------------------------
Msrc/parser.c | 13+++++++------
Msrc/tofu.c | 242++++++++++++++++++++++++++++++++++++++++++++-----------------------------------
Msrc/util.c | 5+++--
11 files changed, 309 insertions(+), 267 deletions(-)

diff --git a/README.md b/README.md @@ -60,6 +60,6 @@ $ make ### Dependencies: - A POSIX-like system and a C11 compiler -- OpenSSL +- [BearSSL](https://www.bearssl.org/index.html) - [scdoc](https://sr.ht/~sircmpwn/scdoc/) (optional) diff --git a/config.sh b/config.sh @@ -117,8 +117,8 @@ run_configure() { fi done - find_library OpenSSL libssl - find_library OpenSSL libcrypto + # XXX: Asked the maintainer to provide a .pc file + LIBS="$LIBS -lbearssl" printf "Checking for scdoc... " if scdoc -v >/dev/null 2>&1 diff --git a/include/gmni/gmni.h b/include/gmni/gmni.h @@ -1,7 +1,7 @@ #ifndef GEMINI_CLIENT_H #define GEMINI_CLIENT_H +#include <bearssl_ssl.h> #include <netdb.h> -#include <openssl/ssl.h> #include <stdbool.h> #include <sys/socket.h> @@ -52,20 +52,16 @@ struct gemini_response { enum gemini_status status; char *meta; + // TODO: Make these private // Response body may be read from here if appropriate: - BIO *bio; + br_sslio_context body; // Connection state - SSL_CTX *ssl_ctx; - SSL *ssl; + br_ssl_client_context *sc; int fd; }; struct gemini_options { - // If NULL, an SSL context will be created. If unset, the ssl field - // must also be NULL. - SSL_CTX *ssl_ctx; - // If ai_family != AF_UNSPEC (the default value on most systems), the // client will connect to this address and skip name resolution. struct addrinfo *addr; @@ -75,6 +71,8 @@ struct gemini_options { struct addrinfo *hints; }; +struct gemini_tofu; + // Requests the specified URL via the gemini protocol. If options is non-NULL, // it may specify some additional configuration to adjust client behavior. // @@ -84,6 +82,7 @@ struct gemini_options { // before exiting or re-using it for another request. enum gemini_result gemini_request(const char *url, struct gemini_options *options, + struct gemini_tofu *tofu, struct gemini_response *resp); // Must be called after gemini_request in order to free up the resources @@ -137,15 +136,20 @@ struct gemini_token { }; struct gemini_parser { - BIO *f; + int (*read)(void *state, void *buf, size_t nbyte); + void *state; char *buf; size_t bufsz; size_t bufln; bool preformatted; }; -// Initializes a text/gemini parser which reads from the specified BIO. -void gemini_parser_init(struct gemini_parser *p, BIO *f); +// Initializes a text/gemini parser. The provided "read" function will be called +// with the provided "state" value in order to obtain more gemtext data. The +// read function should behave like read(3). +void gemini_parser_init(struct gemini_parser *p, + int (*read)(void *state, void *buf, size_t nbyte), + void *state); // Finishes this text/gemini parser and frees up its resources. void gemini_parser_finish(struct gemini_parser *p); diff --git a/include/gmni/tofu.h b/include/gmni/tofu.h @@ -1,9 +1,7 @@ #ifndef GEMINI_TOFU_H #define GEMINI_TOFU_H +#include <bearssl_x509.h> #include <limits.h> -#include <openssl/ssl.h> -#include <openssl/x509.h> -#include <time.h> enum tofu_error { TOFU_VALID, @@ -24,7 +22,6 @@ enum tofu_action { struct known_host { char *host, *fingerprint; - time_t expires; int lineno; struct known_host *next; }; @@ -34,7 +31,23 @@ struct known_host { typedef enum tofu_action (tofu_callback_t)(enum tofu_error error, const char *fingerprint, struct known_host *host, void *data); +struct gemini_tofu; + +struct x509_tofu_context { + const br_x509_class *vtable; + br_x509_decoder_context decoder; + br_x509_pkey *pkey; + br_sha512_context sha512; + unsigned char hash[64]; + struct gemini_tofu *store; + const char *server_name; + int err; +}; + struct gemini_tofu { + struct x509_tofu_context x509_ctx; + br_ssl_client_context sc; + unsigned char iobuf[BR_SSL_BUFSIZE_BIDI]; char known_hosts_path[PATH_MAX+1]; struct known_host *known_hosts; int lineno; @@ -42,8 +55,7 @@ struct gemini_tofu { void *cb_data; }; -void gemini_tofu_init(struct gemini_tofu *tofu, - SSL_CTX *ssl_ctx, tofu_callback_t *cb, void *data); +void gemini_tofu_init(struct gemini_tofu *tofu, tofu_callback_t *cb, void *data); void gemini_tofu_finish(struct gemini_tofu *tofu); #endif diff --git a/include/util.h b/include/util.h @@ -1,5 +1,7 @@ #ifndef GEMINI_UTIL_H #define GEMINI_UTIL_H +#include <stdio.h> +#include <sys/types.h> struct pathspec { const char *var; diff --git a/src/client.c b/src/client.c @@ -1,15 +1,15 @@ #include <assert.h> #include <errno.h> #include <netdb.h> -#include <openssl/bio.h> -#include <openssl/err.h> -#include <openssl/ssl.h> +#include <bearssl_ssl.h> #include <stdlib.h> +#include <stdio.h> #include <string.h> #include <sys/socket.h> #include <sys/types.h> #include <unistd.h> #include <gmni/gmni.h> +#include <gmni/tofu.h> #include <gmni/url.h> static enum gemini_result @@ -88,9 +88,41 @@ gemini_connect(struct Curl_URL *uri, struct gemini_options *options, #define GEMINI_META_MAXLEN 1024 #define GEMINI_STATUS_MAXLEN 2 +static int +sock_read(void *ctx, unsigned char *buf, size_t len) +{ + for (;;) { + ssize_t rlen; + rlen = read(*(int *)ctx, buf, len); + if (rlen <= 0) { + if (rlen < 0 && errno == EINTR) { + continue; + } + return -1; + } + return (int)rlen; + } +} + +static int +sock_write(void *ctx, const unsigned char *buf, size_t len) +{ + for (;;) { + ssize_t wlen; + wlen = write(*(int *)ctx, buf, len); + if (wlen <= 0) { + if (wlen < 0 && errno == EINTR) { + continue; + } + return -1; + } + return (int)wlen; + } +} + enum gemini_result gemini_request(const char *url, struct gemini_options *options, - struct gemini_response *resp) + struct gemini_tofu *tofu, struct gemini_response *resp) { assert(url); assert(resp); @@ -128,84 +160,50 @@ gemini_request(const char *url, struct gemini_options *options, goto cleanup; } - if (options && options->ssl_ctx) { - resp->ssl_ctx = options->ssl_ctx; - SSL_CTX_up_ref(options->ssl_ctx); - } else { - resp->ssl_ctx = SSL_CTX_new(TLS_method()); - assert(resp->ssl_ctx); - SSL_CTX_set_verify(resp->ssl_ctx, SSL_VERIFY_PEER, NULL); - } - int r; - BIO *sbio = BIO_new(BIO_f_ssl()); res = gemini_connect(uri, options, resp, &resp->fd); if (res != GEMINI_OK) { free(host); goto cleanup; } - resp->ssl = SSL_new(resp->ssl_ctx); - assert(resp->ssl); - SSL_set_connect_state(resp->ssl); - if ((r = SSL_set1_host(resp->ssl, host)) != 1) { - free(host); - goto ssl_error; - } - if ((r = SSL_set_tlsext_host_name(resp->ssl, host)) != 1) { - free(host); - goto ssl_error; - } - free(host); - if ((r = SSL_set_fd(resp->ssl, resp->fd)) != 1) { - goto ssl_error; - } - if ((r = SSL_connect(resp->ssl)) != 1) { - goto ssl_error; - } - - X509 *cert = SSL_get_peer_certificate(resp->ssl); - if (!cert) { - resp->status = X509_V_ERR_UNSPECIFIED; - res = GEMINI_ERR_SSL_VERIFY; - goto cleanup; - } - X509_free(cert); - - long vr = SSL_get_verify_result(resp->ssl); - if (vr != X509_V_OK) { - resp->status = vr; - res = GEMINI_ERR_SSL_VERIFY; - goto cleanup; - } - - BIO_set_ssl(sbio, resp->ssl, 0); - - resp->bio = BIO_new(BIO_f_buffer()); - BIO_push(resp->bio, sbio); + // TODO: session reuse + resp->sc = &tofu->sc; + br_ssl_client_reset(resp->sc, host, 0); + br_sslio_init(&resp->body, &resp->sc->eng, + sock_read, &resp->fd, sock_write, &resp->fd); char req[1024 + 3]; r = snprintf(req, sizeof(req), "%s\r\n", url); assert(r > 0); - r = BIO_puts(sbio, req); - if (r == -1) { - res = GEMINI_ERR_IO; - goto cleanup; - } - assert(r == (int)strlen(req)); + br_sslio_write_all(&resp->body, req, r); + br_sslio_flush(&resp->body); + // The SSL engine maintains an internal buffer, so this shouldn't be as + // inefficient as it looks. It's necessary to do this one byte at a time + // to avoid consuming any of the response body buffer. char buf[GEMINI_META_MAXLEN + GEMINI_STATUS_MAXLEN + 2 /* CRLF */ + 1 /* NUL */]; - r = BIO_gets(resp->bio, buf, sizeof(buf)); - if (r == -1) { - res = GEMINI_ERR_IO; - goto cleanup; + memset(buf, 0, sizeof(buf)); + size_t l; + for (l = 0; l < 2 || memcmp(&buf[l-2], "\r\n", 2) != 0; ++l) { + r = br_sslio_read(&resp->body, &buf[l], 1); + if (r < 0) { + break; + } } - if (r < 3 || strcmp(&buf[r - 2], "\r\n") != 0) { - fprintf(stderr, "invalid line %d '%s'\n", r, buf); + int err = br_ssl_engine_last_error(&resp->sc->eng); + if (err != 0) { + // TODO: Bubble this up properly + fprintf(stderr, "SSL error %d\n", err); + goto ssl_error; + } + + if (l < 3 || strcmp(&buf[l-2], "\r\n") != 0) { + fprintf(stderr, "invalid line '%s'\n", buf); res = GEMINI_ERR_PROTOCOL; goto cleanup; } @@ -217,9 +215,9 @@ gemini_request(const char *url, struct gemini_options *options, res = GEMINI_ERR_PROTOCOL; goto cleanup; } - resp->meta = calloc(r - 5 /* 2 digits, space, and CRLF */ + 1 /* NUL */, 1); - strncpy(resp->meta, &endptr[1], r - 5); - resp->meta[r - 5] = '\0'; + resp->meta = calloc(l - 5 /* 2 digits, space, and CRLF */ + 1 /* NUL */, 1); + strncpy(resp->meta, &endptr[1], l - 5); + resp->meta[l - 5] = '\0'; cleanup: curl_url_cleanup(uri); @@ -237,26 +235,18 @@ gemini_response_finish(struct gemini_response *resp) return; } - if (resp->bio) { - BIO_free_all(resp->bio); - resp->bio = NULL; + if (resp->fd != -1) { + close(resp->fd); + resp->fd = -1; } - if (resp->ssl) { - SSL_free(resp->ssl); - } - if (resp->ssl_ctx) { - SSL_CTX_free(resp->ssl_ctx); - } free(resp->meta); - if (resp->fd != -1) { - close(resp->fd); - resp->fd = -1; + if (resp->sc) { + br_sslio_close(&resp->body); } - resp->ssl = NULL; - resp->ssl_ctx = NULL; + resp->sc = NULL; resp->meta = NULL; } @@ -277,11 +267,11 @@ gemini_strerr(enum gemini_result r, struct gemini_response *resp) case GEMINI_ERR_CONNECT: return strerror(errno); case GEMINI_ERR_SSL: - return ERR_error_string( - SSL_get_error(resp->ssl, resp->status), - NULL); + // TODO: more specific + return "SSL error"; case GEMINI_ERR_SSL_VERIFY: - return X509_verify_cert_error_string(resp->status); + // TODO: more specific + return "X.509 certificate not trusted"; case GEMINI_ERR_IO: return "I/O error"; case GEMINI_ERR_PROTOCOL: diff --git a/src/gmni.c b/src/gmni.c @@ -1,9 +1,8 @@ #include <assert.h> +#include <bearssl_ssl.h> #include <errno.h> #include <getopt.h> #include <netdb.h> -#include <openssl/bio.h> -#include <openssl/err.h> #include <stdbool.h> #include <stdio.h> #include <stdlib.h> @@ -222,10 +221,7 @@ main(int argc, char *argv[]) return 1; } - SSL_load_error_strings(); - ERR_load_crypto_strings(); - opts.ssl_ctx = SSL_CTX_new(TLS_method()); - gemini_tofu_init(&cfg.tofu, opts.ssl_ctx, &tofu_callback, &cfg); + gemini_tofu_init(&cfg.tofu, &tofu_callback, &cfg); bool exit = false; struct Curl_URL *url = curl_url(); @@ -242,7 +238,8 @@ main(int argc, char *argv[]) curl_url_get(url, CURLUPART_URL, &buf, 0); struct gemini_response resp; - enum gemini_result r = gemini_request(buf, &opts, &resp); + enum gemini_result r = gemini_request( + buf, &opts, &cfg.tofu, &resp); free(buf); @@ -340,11 +337,8 @@ main(int argc, char *argv[]) char last = 0; char buf[BUFSIZ]; for (int n = 1; n > 0;) { - n = BIO_read(resp.bio, buf, BUFSIZ); - if (n == -1) { - fprintf(stderr, "Error: read\n"); - return 1; - } else if (n != 0) { + n = br_sslio_read(&resp.body, buf, BUFSIZ); + if (n > 0) { last = buf[n - 1]; } ssize_t w = 0; @@ -370,7 +364,6 @@ next: gemini_response_finish(&resp); } - SSL_CTX_free(opts.ssl_ctx); curl_url_cleanup(url); gemini_tofu_finish(&cfg.tofu); return ret; diff --git a/src/gmnlm.c b/src/gmnlm.c @@ -1,22 +1,25 @@ #include <assert.h> +#include <bearssl_ssl.h> #include <ctype.h> +#include <errno.h> +#include <fcntl.h> #include <getopt.h> +#include <gmni/gmni.h> +#include <gmni/tofu.h> +#include <gmni/url.h> #include <libgen.h> #include <limits.h> -#include <openssl/bio.h> -#include <openssl/err.h> #include <regex.h> #include <stdbool.h> #include <stdio.h> +#include <stdlib.h> #include <string.h> #include <sys/ioctl.h> #include <sys/stat.h> +#include <sys/types.h> #include <sys/wait.h> #include <termios.h> #include <unistd.h> -#include <gmni/gmni.h> -#include <gmni/tofu.h> -#include <gmni/url.h> #include "util.h" #define ANSI_COLOR_RED "\x1b[91m" @@ -398,10 +401,13 @@ pipe_resp(FILE *out, struct gemini_response resp, char *cmd) { FILE *f = fdopen(pfd[1], "w"); // XXX: may affect history, do we care? for (int n = 1; n > 0;) { - n = BIO_read(resp.bio, buf, BUFSIZ); - if (n == -1) { - fprintf(stderr, "Error: read\n"); - return; + if (resp.sc) { + n = br_sslio_read(&resp.body, buf, BUFSIZ); + } else { + n = read(resp.fd, buf, BUFSIZ); + } + if (n < 0) { + n = 0; } ssize_t w = 0; while (w < (ssize_t)n) { @@ -445,23 +451,19 @@ do_requests(struct browser *browser, struct gemini_response *resp) break; } - FILE *fp = fopen(path, "r"); - if (!fp) { + int fd = open(path, O_RDONLY); + if (fd < 0) { resp->status = GEMINI_STATUS_NOT_FOUND; - /* Make sure members of resp evaluate to false, so that - gemini_response_finish does not try to free them. */ - resp->bio = NULL; - resp->ssl = NULL; - resp->ssl_ctx = NULL; + // Make sure members of resp evaluate to false, + // so that gemini_response_finish does not try + // to free them. + resp->sc = NULL; resp->meta = NULL; resp->fd = -1; free(path); break; } - BIO *file = BIO_new_fp(fp, BIO_CLOSE); - resp->bio = BIO_new(BIO_f_buffer()); - BIO_push(resp->bio, file); if (has_suffix(path, ".gmi") || has_suffix(path, ".gemini")) { resp->meta = strdup("text/gemini"); } else if (has_suffix(path, ".txt")) { @@ -471,14 +473,14 @@ do_requests(struct browser *browser, struct gemini_response *resp) } free(path); resp->status = GEMINI_STATUS_SUCCESS; - resp->fd = -1; - resp->ssl = NULL; - resp->ssl_ctx = NULL; + resp->fd = fd; + resp->sc = NULL; return GEMINI_OK; } free(scheme); - res = gemini_request(browser->plain_url, &browser->opts, resp); + res = gemini_request(browser->plain_url, &browser->opts, + &browser->tofu, resp); if (res != GEMINI_OK) { fprintf(stderr, "Error: %s\n", gemini_strerr(res, resp)); requesting = false; @@ -835,12 +837,23 @@ wrap(FILE *f, char *s, struct winsize *ws, int *row, int *col) return fprintf(f, "%s\n", s) - 1; } +static int +resp_read(void *state, void *buf, size_t nbyte) +{ + struct gemini_response *resp = state; + if (resp->sc) { + return br_sslio_read(&resp->body, buf, nbyte); + } else { + return read(resp->fd, buf, nbyte); + } +} + static bool display_gemini(struct browser *browser, struct gemini_response *resp) { int nlinks = 0; struct gemini_parser p; - gemini_parser_init(&p, resp->bio); + gemini_parser_init(&p, &resp_read, resp); free(browser->page_title); browser->page_title = NULL; @@ -1029,10 +1042,13 @@ display_plaintext(struct browser *browser, struct gemini_response *resp) char buf[BUFSIZ]; for (int n = 1; n > 0;) { - n = BIO_read(resp->bio, buf, BUFSIZ); - if (n == -1) { - fprintf(stderr, "Error: read\n"); - return 1; + if (resp->sc) { + n = br_sslio_read(&resp->body, buf, BUFSIZ); + } else { + n = read(resp->fd, buf, BUFSIZ); + } + if (n < 0) { + n = 0; } ssize_t w = 0; while (w < (ssize_t)n) { @@ -1207,11 +1223,7 @@ main(int argc, char *argv[]) open_bookmarks(&browser); } - SSL_load_error_strings(); - ERR_load_crypto_strings(); - browser.opts.ssl_ctx = SSL_CTX_new(TLS_method()); - gemini_tofu_init(&browser.tofu, browser.opts.ssl_ctx, - &tofu_callback, &browser); + gemini_tofu_init(&browser.tofu, &tofu_callback, &browser); struct gemini_response resp; browser.running = true; @@ -1273,7 +1285,6 @@ main(int argc, char *argv[]) hist = hist->prev; } history_free(hist); - SSL_CTX_free(browser.opts.ssl_ctx); curl_url_cleanup(browser.url); free(browser.page_title); free(browser.plain_url); diff --git a/src/parser.c b/src/parser.c @@ -1,21 +1,23 @@ #include <assert.h> #include <ctype.h> -#include <openssl/bio.h> #include <stdbool.h> #include <stddef.h> +#include <stdio.h> #include <stdlib.h> #include <string.h> #include <gmni/gmni.h> void -gemini_parser_init(struct gemini_parser *p, BIO *f) +gemini_parser_init(struct gemini_parser *p, + int (*read)(void *state, void *buf, size_t nbyte), + void *state) { - p->f = f; + p->read = read; + p->state = state; p->bufln = 0; p->bufsz = BUFSIZ; p->buf = malloc(p->bufsz + 1); p->buf[0] = 0; - BIO_up_ref(p->f); p->preformatted = false; } @@ -25,7 +27,6 @@ gemini_parser_finish(struct gemini_parser *p) if (!p) { return; } - BIO_free(p->f); free(p->buf); } @@ -42,7 +43,7 @@ gemini_parser_next(struct gemini_parser *p, struct gemini_token *tok) assert(p->buf); } - ssize_t n = BIO_read(p->f, &p->buf[p->bufln], p->bufsz - p->bufln - 1); + int n = p->read(p->state, &p->buf[p->bufln], p->bufsz - p->bufln - 1); if (n == -1) { return -1; } else if (n == 0) { diff --git a/src/tofu.c b/src/tofu.c @@ -1,95 +1,97 @@ #include <assert.h> +#include <bearssl_hash.h> +#include <bearssl_x509.h> #include <errno.h> +#include <gmni/gmni.h> +#include <gmni/tofu.h> #include <libgen.h> #include <limits.h> -#include <openssl/asn1.h> -#include <openssl/evp.h> -#include <openssl/ssl.h> -#include <openssl/x509.h> -#include <openssl/x509v3.h> +#include <stdint.h> #include <stdio.h> +#include <stdlib.h> #include <string.h> -#include <time.h> -#include <gmni/gmni.h> -#include <gmni/tofu.h> #include "util.h" -static int -verify_callback(X509_STORE_CTX *ctx, void *data) +static void +xt_start_chain(const br_x509_class **ctx, const char *server_name) { - // Gemini clients handle TLS verification differently from the rest of - // the internet. We use a TOFU system, so trust is based on two factors: - // - // - Is the certificate valid at the time of the request? - // - Has the user trusted this certificate yet? - // - // If the answer to the latter is "no", then we give the user an - // opportunity to explicitly agree to trust the certificate before - // rejecting it. - // - // If you're reading this code with the intent to re-use it for - // something unrelated to Gemini, think twice. - struct gemini_tofu *tofu = (struct gemini_tofu *)data; - X509 *cert = X509_STORE_CTX_get0_cert(ctx); - struct known_host *host = NULL; - - int rc; - int day, sec; - const ASN1_TIME *notBefore = X509_get0_notBefore(cert); - const ASN1_TIME *notAfter = X509_get0_notAfter(cert); - if (!ASN1_TIME_diff(&day, &sec, NULL, notBefore)) { - rc = X509_V_ERR_UNSPECIFIED; - goto invalid_cert; - } - if (day > 0 || sec > 0) { - rc = X509_V_ERR_CERT_NOT_YET_VALID; - goto invalid_cert; - } - if (!ASN1_TIME_diff(&day, &sec, NULL, notAfter)) { - rc = X509_V_ERR_UNSPECIFIED; - goto invalid_cert; - } - if (day < 0 || sec < 0) { - rc = X509_V_ERR_CERT_HAS_EXPIRED; - goto invalid_cert; - } - - unsigned char md[512 / 8]; - const EVP_MD *sha512 = EVP_sha512(); - unsigned int len = sizeof(md); - rc = X509_digest(cert, sha512, md, &len); - assert(rc == 1); + struct x509_tofu_context *cc = (struct x509_tofu_context *)(void *)ctx; + cc->server_name = server_name; + cc->err = 0; + cc->pkey = NULL; +} - char fingerprint[512 / 8 * 3]; - for (size_t i = 0; i < sizeof(md); ++i) { - snprintf(&fingerprint[i * 3], 4, "%02X%s", - md[i], i + 1 == sizeof(md) ? "" : ":"); +static void +xt_start_cert(const br_x509_class **ctx, uint32_t length) +{ + struct x509_tofu_context *cc = (struct x509_tofu_context *)(void *)ctx; + if (cc->err != 0) { + return; + } + if (length == 0) { + cc->err = BR_ERR_X509_TRUNCATED; + return; } + br_x509_decoder_init(&cc->decoder, NULL, NULL); + br_sha512_init(&cc->sha512); +} - SSL *ssl = X509_STORE_CTX_get_ex_data(ctx, - SSL_get_ex_data_X509_STORE_CTX_idx()); - const char *servername = SSL_get_servername(ssl, TLSEXT_NAMETYPE_host_name); - if (!servername) { - rc = X509_V_ERR_HOSTNAME_MISMATCH; - goto invalid_cert; +static void +xt_append(const br_x509_class **ctx, const unsigned char *buf, size_t len) +{ + struct x509_tofu_context *cc = (struct x509_tofu_context *)(void *)ctx; + if (cc->err != 0) { + return; + } + br_x509_decoder_push(&cc->decoder, buf, len); + int err = br_x509_decoder_last_error(&cc->decoder); + if (err != 0 && err != BR_ERR_X509_TRUNCATED) { + cc->err = err; + } + br_sha512_update(&cc->sha512, buf, len); +} + +static void +xt_end_cert(const br_x509_class **ctx) +{ + struct x509_tofu_context *cc = (struct x509_tofu_context *)(void *)ctx; + if (cc->err != 0) { + return; + } + int err = br_x509_decoder_last_error(&cc->decoder); + if (err != 0 && err != BR_ERR_X509_TRUNCATED) { + cc->err = err; + return; } + if (br_x509_decoder_isCA(&cc->decoder)) { + return; + } + cc->pkey = br_x509_decoder_get_pkey(&cc->decoder); + br_sha512_out(&cc->sha512, &cc->hash); +} - rc = X509_check_host(cert, servername, strlen(servername), 0, NULL); - if (rc != 1) { - rc = X509_V_ERR_HOSTNAME_MISMATCH; - goto invalid_cert; +static unsigned +xt_end_chain(const br_x509_class **ctx) +{ + struct x509_tofu_context *cc = (struct x509_tofu_context *)(void *)ctx; + if (cc->err != 0) { + return (unsigned)cc->err; + } + if (!cc->pkey) { + return BR_ERR_X509_EMPTY_CHAIN; } - time_t now; - time(&now); + char fingerprint[512 / 8 * 3]; + for (size_t i = 0; i < sizeof(cc->hash); ++i) { + snprintf(&fingerprint[i * 3], 4, "%02X%s", + cc->hash[i], i + 1 == sizeof(cc->hash) ? "" : ":"); + } enum tofu_error error = TOFU_UNTRUSTED_CERT; - host = tofu->known_hosts; + (void)error; + struct known_host *host = cc->store->known_hosts; while (host) { - if (host->expires < now) { - goto next; - } - if (strcmp(host->host, servername) != 0) { + if (strcmp(host->host, cc->server_name) != 0) { goto next; } if (strcmp(host->fingerprint, fingerprint) == 0) { @@ -102,66 +104,84 @@ next: host = host->next; } - rc = X509_V_ERR_CERT_UNTRUSTED; - -callback: - switch (tofu->callback(error, fingerprint, host, tofu->cb_data)) { + switch (cc->store->callback(error, fingerprint, + host, cc->store->cb_data)) { case TOFU_ASK: assert(0); // Invariant case TOFU_FAIL: - X509_STORE_CTX_set_error(ctx, rc); - break; + return BR_ERR_X509_NOT_TRUSTED; case TOFU_TRUST_ONCE: // No further action necessary return 0; case TOFU_TRUST_ALWAYS:; - FILE *f = fopen(tofu->known_hosts_path, "a"); + FILE *f = fopen(cc->store->known_hosts_path, "a"); if (!f) { fprintf(stderr, "Error opening %s for writing: %s\n", - tofu->known_hosts_path, strerror(errno)); + cc->store->known_hosts_path, strerror(errno)); break; }; - struct tm expires_tm; - ASN1_TIME_to_tm(notAfter, &expires_tm); - time_t expires = mktime(&expires_tm); - fprintf(f, "%s %s %s %jd\n", servername, - "SHA-512", fingerprint, (intmax_t)expires); + fprintf(f, "%s %s %s\n", cc->server_name, + "SHA-512", fingerprint); fclose(f); host = calloc(1, sizeof(struct known_host)); - host->host = strdup(servername); + host->host = strdup(cc->server_name); host->fingerprint = strdup(fingerprint); - host->expires = expires; - host->lineno = ++tofu->lineno; - host->next = tofu->known_hosts; - tofu->known_hosts = host; + host->lineno = ++cc->store->lineno; + host->next = cc->store->known_hosts; + cc->store->known_hosts = host; return 0; } - X509_STORE_CTX_set_error(ctx, rc); - return 0; + assert(0); // Unreachable +} -invalid_cert: - error = TOFU_INVALID_CERT; - goto callback; +static const br_x509_pkey * +xt_get_pkey(const br_x509_class *const *ctx, unsigned *usages) +{ + struct x509_tofu_context *cc = (struct x509_tofu_context *)(void *)ctx; + if (cc->err != 0) { + return NULL; + } + if (usages) { + // XXX: BearSSL doesn't pull the usages out of the X.509 for us + *usages = BR_KEYTYPE_KEYX | BR_KEYTYPE_SIGN; + } + return cc->pkey; } +const br_x509_class xt_vtable = { + sizeof(struct x509_tofu_context), + xt_start_chain, + xt_start_cert, + xt_append, + xt_end_cert, + xt_end_chain, + xt_get_pkey, +}; + +static void +x509_init_tofu(struct x509_tofu_context *ctx, struct gemini_tofu *store) +{ + ctx->vtable = &xt_vtable; + ctx->store = store; +} void -gemini_tofu_init(struct gemini_tofu *tofu, - SSL_CTX *ssl_ctx, tofu_callback_t *cb, void *cb_data) +gemini_tofu_init(struct gemini_tofu *tofu, tofu_callback_t *cb, void *cb_data) { const struct pathspec paths[] = { {.var = "GMNIDATA", .path = "/%s"}, - {.var = "XDG_DATA_HOME", .path = "/gemini/%s"}, - {.var = "HOME", .path = "/.local/share/gemini/%s"} + {.var = "XDG_DATA_HOME", .path = "/gmni/%s"}, + {.var = "HOME", .path = "/.local/share/gmni/%s"} }; char *path_fmt = getpath(paths, sizeof(paths) / sizeof(paths[0])); char dname[PATH_MAX+1]; size_t n = 0; - n = snprintf(tofu->known_hosts_path, sizeof(tofu->known_hosts_path), - path_fmt, "known_hosts"); + n = snprintf(tofu->known_hosts_path, + sizeof(tofu->known_hosts_path), + path_fmt, "known_hosts"); assert(n < sizeof(tofu->known_hosts_path)); strncpy(dname, dirname(tofu->known_hosts_path), sizeof(dname)-1); @@ -179,10 +199,17 @@ gemini_tofu_init(struct gemini_tofu *tofu, tofu->callback = cb; tofu->cb_data = cb_data; - SSL_CTX_set_cert_verify_callback(ssl_ctx, verify_callback, tofu); tofu->known_hosts = NULL; + x509_init_tofu(&tofu->x509_ctx, tofu); + + br_x509_minimal_context _; // Discarded + br_ssl_client_init_full(&tofu->sc, &_, NULL, 0); + br_ssl_engine_set_x509(&tofu->sc.eng, &tofu->x509_ctx.vtable); + br_ssl_engine_set_buffer(&tofu->sc.eng, + &tofu->iobuf, sizeof(tofu->iobuf), 1); + FILE *f = fopen(tofu->known_hosts_path, "r"); if (!f) { return; @@ -191,6 +218,11 @@ gemini_tofu_init(struct gemini_tofu *tofu, int lineno = 1; char *line = NULL; while (getline(&line, &n, f) != -1) { + int ln = strlen(line); + if (line[ln-1] == '\n') { + line[ln-1] = 0; + } + struct known_host *host = calloc(1, sizeof(struct known_host)); char *tok = strtok(line, " "); assert(tok); @@ -208,10 +240,6 @@ gemini_tofu_init(struct gemini_tofu *tofu, assert(tok); host->fingerprint = strdup(tok); - tok = strtok(NULL, " "); - assert(tok); - host->expires = strtoul(tok, NULL, 10); - host->lineno = lineno++; host->next = tofu->known_hosts; diff --git a/src/util.c b/src/util.c @@ -1,5 +1,7 @@ #include <assert.h> +#include <bearssl_ssl.h> #include <errno.h> +#include <gmni/gmni.h> #include <libgen.h> #include <limits.h> #include <stdint.h> @@ -7,7 +9,6 @@ #include <stdlib.h> #include <string.h> #include <sys/stat.h> -#include <gmni/gmni.h> #include "util.h" static void @@ -82,7 +83,7 @@ download_resp(FILE *out, struct gemini_response resp, const char *path, fprintf(out, "Downloading %s to %s\n", url, path); char buf[BUFSIZ]; for (int n = 1; n > 0;) { - n = BIO_read(resp.bio, buf, sizeof(buf)); + n = br_sslio_read(&resp.body, buf, sizeof(buf)); if (n == -1) { fprintf(stderr, "Error: read\n"); return 1;