PEM encode/decoding functions.

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@21307 ec53bebd-3082-4978-b11e-865c3cabbd6b

lib/hx509/file.c

@@ -135,6 +135,10 @@ _hx509_write_file(const char *fn, const void *data, size_t length)
     return 0;
 }
 
+/*
+ *
+ */
+
 static void
 header(FILE *f, const char *type, const char *str)
 {
@@ -143,22 +147,23 @@ header(FILE *f, const char *type, const char *str)
 
 int
 hx509_pem_write(hx509_context context, const char *type, 
-		char **headers, FILE *f,
+		hx509_pem_header *headers, FILE *f,
 		const void *data, size_t size)
 {
     const char *p = data;
     size_t length;
     char *line;
-    int i;
 
 #define ENCODE_LINE_LENGTH	54
     
     header(f, "BEGIN", type);
 
-    for(i = 0; headers && headers[i]; i++)
+    while (headers) {
-	fprintf(f, "%s\n", headers[i]);
+	fprintf(f, "%s: %s\n%s", 
-    if (i > 0)
+		headers->header, headers->value,
-	fprintf(f, "\n");
+		headers->next ? "" : "\n");
+	headers = headers->next;
+    }
 
     while (size > 0) {
 	ssize_t l;
@@ -183,3 +188,189 @@ hx509_pem_write(hx509_context context, const char *type,
 
     return 0;
 }
+
+/*
+ *
+ */
+
+int
+hx509_pem_add_header(hx509_pem_header **headers, 
+		     const char *header, const char *value)
+{
+    hx509_pem_header *h;
+
+    h = calloc(1, sizeof(*h));
+    if (h == NULL)
+	return ENOMEM;
+    h->header = strdup(header);
+    if (h->header == NULL) {
+	free(h);
+	return ENOMEM;
+    }
+    h->value = strdup(value);
+    if (h->value == NULL) {
+	free(h->header);
+	free(h);
+	return ENOMEM;
+    }
+
+    h->next = *headers;
+    *headers = h;
+
+    return 0;
+}
+
+void
+hx509_pem_free_header(hx509_pem_header *headers)
+{
+    hx509_pem_header *h;
+    while (headers) {
+	h = headers;
+	headers = headers->next;
+	free(h->header);
+	free(h->value);
+	free(h);
+    }
+}
+
+/*
+ *
+ */
+
+const char *
+hx509_pem_find_header(const hx509_pem_header *h, const char *header)
+{
+    while(h) {
+	if (strcmp(header, h->header) == 0)
+	    return h->value;
+	h = h->next;
+    }
+    return NULL;
+}
+
+
+/*
+ *
+ */
+
+int
+hx509_pem_read(hx509_context context,
+	       FILE *f, 
+	       hx509_pem_read_func func,
+	       void *ctx)
+{
+    hx509_pem_header *headers = NULL;
+    char *type = NULL;
+    void *data = NULL;
+    size_t len = 0;
+    char buf[1024];
+    int ret = HX509_PARSING_KEY_FAILED;
+
+    enum { BEFORE, SEARCHHEADER, INHEADER, INDATA, DONE } where;
+
+    where = BEFORE;
+
+    while (fgets(buf, sizeof(buf), f) != NULL) {
+	char *p;
+	int i;
+
+	i = strcspn(buf, "\n");
+	if (buf[i] == '\n') {
+	    buf[i] = '\0';
+	    if (i > 0)
+		i--;
+	}
+	if (buf[i] == '\r') {
+	    buf[i] = '\0';
+	    if (i > 0)
+		i--;
+	}
+	    
+	switch (where) {
+	case BEFORE:
+	    if (strncmp("-----BEGIN ", buf, 11) == 0) {
+		type = strdup(buf + 11);
+		if (type == NULL)
+		    break;
+		p = strchr(type, '-');
+		if (p)
+		    *p = '\0';
+		where = SEARCHHEADER;
+	    }
+	    break;
+	case SEARCHHEADER:
+	    p = strchr(buf, ':');
+	    if (p == NULL) {
+		where = INDATA;
+		goto indata;
+	    }
+	    /* FALLTHOUGH */
+	case INHEADER:
+	    if (buf[0] == '\0') {
+		where = INDATA;
+		break;
+	    }
+	    p = strchr(buf, ':');
+	    if (p) {
+		*p++ = '\0';
+		while (isspace((int)*p))
+		    p++;
+		ret = hx509_pem_add_header(&headers, buf, p);
+		if (ret)
+		    abort();
+	    }
+	    break;
+	case INDATA:
+	indata:
+
+	    if (strncmp("-----END ", buf, 9) == 0) {
+		where = DONE;
+		break;
+	    }
+
+	    p = emalloc(i);
+	    i = base64_decode(buf, p);
+	    if (i < 0) {
+		free(p);
+		goto out;
+	    }
+	    
+	    data = erealloc(data, len + i);
+	    memcpy(((char *)data) + len, p, i);
+	    free(p);
+	    len += i;
+	    break;
+	case DONE:
+	    abort();
+	}
+
+	if (where == DONE) {
+	    ret = (*func)(context, type, headers, data, len, ctx);
+	out:
+	    free(data);
+	    data = NULL;
+	    len = 0;
+	    free(type);
+	    type = NULL;
+	    where = BEFORE;
+	    hx509_pem_free_header(headers);
+	    headers = NULL;
+	    if (ret)
+		break;
+	}
+    }
+
+    if (where != BEFORE) {
+	hx509_set_error_string(context, 0, HX509_PARSING_KEY_FAILED,
+			       "File ends before end of PEM end tag");
+	ret = HX509_PARSING_KEY_FAILED;
+    }
+    if (data)
+	free(data);
+    if (type)
+	free(type);
+    if (headers)
+	hx509_pem_free_header(headers);
+
+    return ret;
+}